minor refactor to blocksplit

credit to oss-fuzz

In rare circumstances, the block-splitter might cut a block at the exact beginning of a repcode.
In which case, since litlength=0, if the repcode expected 1+ literals in front, its signification changes.
This scenario is controlled in ZSTD_seqStore_resolveOffCodes(),
and the repcode is transformed into a raw offset when its new meaning is incorrect.

In more complex scenarios, the previous block might be emitted as uncompressed after all,
thus modifying the expected repcode history.
In the case discovered by oss-fuzz, the first block is emitted as uncompressed,
so the repcode history remains at default values: 1,4,8.

But since the starting repcode is repcode3, and the literal length is == 0,
its meaning is : = repcode1 - 1.
Since repcode1==1, it results in an offset value of 0, which is invalid.

So that's what the `assert()` was verifying : the result of the repcode translation should be a valid offset.

But actually, it doesn't matter, because this result will then be compared to reality,
and since it's an invalid offset, it will necessarily be discarded if incorrect,
then the repcode will be replaced by a raw offset.

So the `assert()` is not useful.
Furthermore, it's incorrect, because it assumes this situation cannot happen, but it does, as described in above scenario.

.circleci/config.yml

@@ -7,19 +7,21 @@ jobs:
     #       preinstalled to reduce installation time.
     docker:
       - image: fbopensource/zstd-circleci-primary:0.0.1
+    # TODO: Re-enable aarch64 build:
+    #       make aarch64build     && make clean
     steps:
       - checkout
       - run:
           name: Test
           command: |
             ./tests/test-license.py
-            cc -v; CFLAGS="-O0 -Werror -pedantic" make all && make clean
-            make c99build         ; make clean
-            make c11build         ; make clean
-            make aarch64build     ; make clean
+            cc -v
+            CFLAGS="-O0 -Werror -pedantic" make allmost; make clean
+            make c99build; make clean
+            make c11build; make clean
             make -j regressiontest; make clean
-            make shortest         ; make clean
-            make cxxtest          ; make clean
+            make shortest; make clean
+            make cxxtest; make clean
   # the second half of the jobs are in this test
   short-tests-1:
     docker:
@@ -84,31 +86,10 @@ workflows:
   commit:
     jobs:
       # Run the tests in parallel
-      - short-tests-0:
-          filters:
-            tags:
-              only: /.*/
-      - short-tests-1:
-          filters:
-            tags:
-              only: /.*/
-      # Create a branch called regression and set it to dev to force a
-      # regression test run
-      - regression-test:
-          filters:
-            branches:
-              only:
-                - regression
-      # Only run on release tags.
-      - publish-github-release:
-          requires:
-            - short-tests-0
-            - short-tests-1
-          filters:
-            branches:
-              ignore: /.*/
-            tags:
-              only: /^v\d+\.\d+\.\d+$/
+      - short-tests-0
+      - short-tests-1
+      - regression-test
+
   nightly:
     triggers:
       - schedule:
@@ -120,7 +101,7 @@ workflows:
                 - dev
                 - master
     jobs:
-      # Run daily long regression tests
+      # Run daily regression tests
       - regression-test
 
 

.github/workflows/dev-long-tests.yml

@@ -0,0 +1,240 @@
+name: dev-long-tests
+# Tests longer than 10mn
+
+concurrency:
+  group: long-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  pull_request:
+    branches: [ dev, release, actionsTest ]
+
+jobs:
+  make-all:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: make all
+      run: make all
+
+  # lasts ~24mn
+  make-test:
+    runs-on: ubuntu-latest
+    env:
+      DEVNULLRIGHTS: 1
+      READFROMBLOCKDEVICE: 1
+    steps:
+    - uses: actions/checkout@v2
+    - name: make test
+      run: make test
+
+  # lasts ~26mn
+  make-test-osx:
+    runs-on: macos-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: OS-X test
+      run: make test # make -c lib all doesn't work because of the fact that it's not a tty
+
+  no-intrinsics-fuzztest:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: no intrinsics fuzztest
+      run: MOREFLAGS="-DZSTD_NO_INTRINSICS" make -C tests fuzztest
+
+  tsan-zstreamtest:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: thread sanitizer zstreamtest
+      run: CC=clang ZSTREAM_TESTTIME=-T3mn make tsan-test-zstream
+
+  # lasts ~15mn
+  tsan-fuzztest:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: thread sanitizer fuzztest
+      run: CC=clang make tsan-fuzztest
+
+  # lasts ~23mn
+  gcc-8-asan-ubsan-testzstd:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: gcc-8 + ASan + UBSan + Test Zstd
+      run: |
+        sudo apt-get -qqq update
+        make gcc8install
+        CC=gcc-8 make -j uasan-test-zstd </dev/null V=1
+
+  gcc-asan-ubsan-testzstd-32bit:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: ASan + UBSan + Test Zstd, 32bit mode
+      run: |
+        make libc6install
+        make -j uasan-test-zstd32 V=1
+
+    # Note : external libraries must be turned off when using MSAN tests,
+    # because they are not msan-instrumented,
+    # so any data coming from these libraries is always considered "uninitialized"
+
+  gcc-8-asan-ubsan-fuzz:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: gcc-8 + ASan + UBSan + Fuzz Test
+      run: |
+        make gcc8install
+        CC=gcc-8 FUZZER_FLAGS="--long-tests" make clean uasan-fuzztest
+
+  gcc-asan-ubsan-fuzz32:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: ASan + UBSan + Fuzz Test 32bit
+      run: |
+        make libc6install
+        CFLAGS="-O3 -m32" FUZZER_FLAGS="--long-tests" make uasan-fuzztest
+
+  asan-ubsan-regression:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: ASan + UBSan + Regression Test
+      run: make -j uasanregressiontest
+
+  msan-regression:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: MSan + Regression Test
+      run: make -j msanregressiontest
+
+  clang-msan-fuzz:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: clang + MSan + Fuzz Test
+      run: |
+        sudo apt-get -qqq update
+        sudo apt-get install clang
+        CC=clang FUZZER_FLAGS="--long-tests" make clean msan-fuzztest
+
+  # lasts ~24mn
+  clang-msan-testzstd:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: clang + MSan + Test Zstd
+      run: |
+        sudo apt-get update
+        sudo apt-get install clang
+        CC=clang make msan-test-zstd HAVE_ZLIB=0 HAVE_LZ4=0 HAVE_LZMA=0 V=1
+
+  armfuzz:
+      runs-on: ubuntu-latest
+      steps:
+      - uses: actions/checkout@v2
+      - name: Qemu ARM emulation + Fuzz Test
+        run: |
+          sudo apt-get -qqq update
+          make arminstall
+          make armfuzz
+
+  valgrind-fuzz-test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: valgrind + fuzz test stack mode    # ~ 7mn
+      shell: 'script -q -e -c "bash {0}"'
+      run: |
+        make valgrindinstall
+        make -C tests valgrindTest
+        make clean
+        make -C tests test-fuzzer-stackmode
+
+  mingw-long-test:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include: [
+          { compiler: clang, platform: x64, action: build, script: "MOREFLAGS='--target=x86_64-w64-mingw32 -Werror -Wconversion -Wno-sign-conversion -Wno-unused-command-line-argument -Wno-implicit-int-float-conversion' make -j allzstd V=1"},
+          { compiler: gcc, platform: x64, action: test, script: ""},
+        ]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Mingw long test
+      run: |
+        $env:PATH_ORIGINAL = $env:PATH
+        $env:PATH_MINGW32 = "C:\msys64\mingw32\bin"
+        $env:PATH_MINGW64 = "C:\msys64\mingw64\bin"
+        COPY C:\msys64\usr\bin\make.exe C:\msys64\mingw32\bin\make.exe
+        COPY C:\msys64\usr\bin\make.exe C:\msys64\mingw64\bin\make.exe
+        IF ("${{matrix.platform}}" -eq "x64")
+        {
+            $env:PATH = $env:PATH_MINGW64 + ";" + $env:PATH_ORIGINAL
+        }
+        ELSEIF ("${{matrix.platform}}" -eq "x86")
+        {
+            $env:PATH = $env:PATH_MINGW32 + ";" + $env:PATH_ORIGINAL
+        }
+        IF ("${{matrix.action}}" -eq "build")
+        {
+          make -v
+          sh -c "${{matrix.compiler}} -v"
+          ECHO "Building zlib to static link"
+          $env:CC = "${{matrix.compiler}}"
+          sh -c "cd .. && git clone --depth 1 --branch v1.2.11 https://github.com/madler/zlib"
+          sh -c "cd ../zlib && make -f win32/Makefile.gcc libz.a"
+          ECHO "Building zstd"
+          $env:CPPFLAGS = "-I../../zlib"
+          $env:LDFLAGS = "../../zlib/libz.a"
+          sh -c "${{matrix.script}}"
+        }
+        ELSEIF ("${{matrix.action}}" -eq "test")
+        {
+            ECHO "Testing ${{matrix.compiler}} ${{matrix.platform}}"
+            $env:CC = "gcc"
+            $env:CXX = "g++"
+            MKDIR build\cmake\build
+            CD build\cmake\build
+            $env:FUZZERTEST = "-T2mn"
+            $env:ZSTREAM_TESTTIME = "-T2mn"
+            cmake -G "Visual Studio 14 2015 Win64" ..
+            cd ..\..\..
+            make clean
+        }
+
+  # lasts ~20mn
+  oss-fuzz:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        sanitizer: [address, undefined, memory]
+    steps:
+    - name: Build Fuzzers (${{ matrix.sanitizer }})
+      id: build
+      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
+      with:
+        oss-fuzz-project-name: 'zstd'
+        dry-run: false
+        sanitizer: ${{ matrix.sanitizer }}
+    - name: Run Fuzzers (${{ matrix.sanitizer }})
+      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
+      with:
+        oss-fuzz-project-name: 'zstd'
+        fuzz-seconds: 600
+        dry-run: false
+        sanitizer: ${{ matrix.sanitizer }}
+    - name: Upload Crash
+      uses: actions/upload-artifact@v1
+      if: failure() && steps.build.outcome == 'success'
+      with:
+        name: ${{ matrix.sanitizer }}-artifacts
+        path: ./out/artifacts

.github/workflows/dev-short-tests.yml

@@ -0,0 +1,448 @@
+name: dev-short-tests
+# Faster tests: mostly build tests, along with some other
+# misc tests
+
+concurrency:
+  group: fast-${{ github.ref }}
+  cancel-in-progress: true
+
+on:
+  pull_request:
+    branches: [ dev, release, actionsTest ]
+
+jobs:
+  linux-kernel:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: linux kernel, library + build + test
+      run: make -C contrib/linux-kernel test CFLAGS="-Werror -Wunused-const-variable -Wunused-but-set-variable"
+
+  benchmarking:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: make benchmarking
+      run: make benchmarking
+
+  check-32bit: # designed to catch https://github.com/facebook/zstd/issues/2428
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: make check on 32-bit
+      run: |
+        sudo apt update
+        APT_PACKAGES="gcc-multilib" make apt-install
+        CFLAGS="-m32 -O1 -fstack-protector" make check V=1
+
+  check-x32:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: make check on x32 ABI # https://en.wikipedia.org/wiki/X32_ABI
+      env:
+        CHECK_CONSTRAINED_MEM: true
+      run: |
+        sudo apt update
+        APT_PACKAGES="gcc-multilib" make apt-install
+        CFLAGS="-mx32 -O1 -fstack-protector" make check V=1
+
+  gcc-7-libzstd:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: gcc-7 + libzstdmt compilation
+      run: |
+        sudo apt-get -qqq update
+        make gcc7install
+        CC=gcc-7 CFLAGS=-Werror make -j all
+        make clean
+        LDFLAGS=-Wl,--no-undefined make -C lib libzstd-mt
+
+    # candidate test (to check) : underlink test
+    # LDFLAGS=-Wl,--no-undefined : will make the linker fail if dll is underlinked
+
+  cmake-build-and-test-check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: cmake build and test check
+      run: |
+        FUZZERTEST=-T1mn ZSTREAM_TESTTIME=-T1mn make cmakebuild
+        cp -r ./ "../zstd source"
+        cd "../zstd source"
+        FUZZERTEST=-T1mn ZSTREAM_TESTTIME=-T1mn make cmakebuild
+
+  cpp-gnu90-c99-compatibility:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: C++, gnu90 and c99 compatibility
+      run: |
+        make cxxtest
+        make clean
+        make gnu90build
+        make clean
+        make c99build
+        make clean
+        make travis-install   # just ensures `make install` works
+
+  mingw-cross-compilation:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: mingw cross-compilation
+      run: |
+        # sudo update-alternatives --set x86_64-w64-mingw32-g++ /usr/bin/x86_64-w64-mingw32-g++-posix; (doesn't work)
+        sudo apt-get -qqq update
+        sudo apt-get install gcc-mingw-w64
+        CC=x86_64-w64-mingw32-gcc CXX=x86_64-w64-mingw32-g++ CFLAGS="-Werror -O1" make zstd
+
+  armbuild:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: ARM Build Test
+      run: |
+        sudo apt-get -qqq update
+        make arminstall
+        make armbuild
+
+  bourne-shell:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Bourne shell compatibility (shellcheck)
+      run: |
+        wget https://github.com/koalaman/shellcheck/releases/download/v0.7.1/shellcheck-v0.7.1.linux.x86_64.tar.xz
+        tar -xf shellcheck-v0.7.1.linux.x86_64.tar.xz
+        shellcheck-v0.7.1/shellcheck --shell=sh --severity=warning --exclude=SC2010 tests/playTests.sh
+
+  zlib-wrapper:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: zlib wrapper test
+      run: |
+        sudo apt-get -qqq update
+        make valgrindinstall
+        make -C zlibWrapper test
+        make -C zlibWrapper valgrindTest
+
+  lz4-threadpool-libs:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: LZ4, thread pool, and libs build testslib wrapper test
+      run: |
+        make lz4install
+        make -C tests test-lz4
+        make check < /dev/null | tee   # mess with lz4 console detection
+        make clean
+        make -C tests test-pool
+        make clean
+        bash tests/libzstd_builds.sh
+
+  gcc-make-tests-32bit:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Make all, 32bit mode
+      run: |
+        sudo apt-get -qqq update
+        make libc6install
+        CFLAGS="-Werror -m32" make -j all32
+
+  gcc-8-make:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: gcc-8 build
+        run: |
+          sudo apt-get -qqq update
+          make gcc8install
+          CC=gcc-8 CFLAGS="-Werror" make -j all
+
+  implicit-fall-through:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: -Wimplicit-fallthrough build
+        run: |
+          make clean
+          CC=gcc MOREFLAGS="-Werror -Wimplicit-fallthrough=2 -O0" make -C lib -j libzstd.a ZSTD_LEGACY_SUPPORT=0
+          make clean
+          CC=clang MOREFLAGS="-Werror -Wimplicit-fallthrough -O0" make -C lib -j libzstd.a ZSTD_LEGACY_SUPPORT=0
+
+  cmake-visual-2019:
+    runs-on: windows-latest
+    strategy:
+      matrix:
+        include:
+          - generator: "Visual Studio 16 2019"
+            flags: "-A x64"
+          - generator: "Visual Studio 16 2019"
+            flags: "-A Win32"
+          - generator: "MinGW Makefiles"
+    steps:
+    - uses: actions/checkout@v2
+    - name: Add MSBuild to PATH
+      uses: microsoft/setup-msbuild@v1.0.2
+    - name: Build
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      run: |
+        cd build\cmake
+        mkdir build
+        cd build
+        cmake.exe -G "${{matrix.generator}}" ${{matrix.flags}} ..
+        cmake.exe --build .
+
+  visual-2019:
+    runs-on: windows-latest
+    strategy:
+      matrix:
+        platform: [x64, Win32]
+        configuration: [Debug, Release]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Add MSBuild to PATH
+      uses: microsoft/setup-msbuild@v1.0.2
+    - name: Build
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      # See https://docs.microsoft.com/visualstudio/msbuild/msbuild-command-line-reference
+      run: >
+        msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v142
+        /t:Clean,Build /p:Platform=${{matrix.platform}} /p:Configuration=${{matrix.configuration}}
+
+  visual-2015:
+    # only GH actions windows-2016 contains VS 2015
+    runs-on: windows-2016
+    strategy:
+      matrix:
+        platform: [x64, Win32]
+        configuration: [Debug, Release]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Add MSBuild to PATH
+      uses: microsoft/setup-msbuild@v1.0.2
+    - name: Build
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      run: >
+        msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v140
+        /t:Clean,Build /p:Platform=${{matrix.platform}} /p:Configuration=${{matrix.configuration}}
+
+  minimal-decompressor-macros:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: minimal decompressor macros
+      run: |
+        make clean && make -j all ZSTD_LIB_MINIFY=1 MOREFLAGS="-Werror"
+        make clean && make check ZSTD_LIB_MINIFY=1 MOREFLAGS="-Werror"
+        make clean && make -j all MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X1 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT"
+        make clean && make check MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X1 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT"
+        make clean && make -j all MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X2 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG"
+        make clean && make check MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X2 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG"
+        make clean && make -j all MOREFLAGS="-Werror -DZSTD_NO_INLINE -DZSTD_STRIP_ERROR_STRINGS"
+        make clean && make check MOREFLAGS="-Werror -DZSTD_NO_INLINE -DZSTD_STRIP_ERROR_STRINGS"
+
+  dynamic-bmi2:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: dynamic bmi2 tests
+      run: |
+        make clean && make -j check MOREFLAGS="-O0 -Werror -mbmi2"
+        make clean && make -j check MOREFLAGS="-O0 -Werror -DDYNAMIC_BMI2=1"
+        make clean && make -j check MOREFLAGS="-O0 -Werror -DDYNAMIC_BMI2=1 -mbmi2"
+        make clean && make -j check MOREFLAGS="-O0 -Werror -DDYNAMIC_BMI2=0"
+        make clean && make -j check MOREFLAGS="-O0 -Werror -DDYNAMIC_BMI2=0 -mbmi2"
+
+  test-variants:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: make all variants & validate
+      run: |
+        make -j -C programs allVariants MOREFLAGS=-O0
+        ./tests/test-variants.sh
+
+
+  qemu-consistency:
+    name: QEMU ${{ matrix.name }}
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false  # 'false' means Don't stop matrix workflows even if some matrix failed.
+      matrix:
+        include: [
+          { name: ARM,      xcc_pkg: gcc-arm-linux-gnueabi,     xcc: arm-linux-gnueabi-gcc,     xemu_pkg: qemu-system-arm,    xemu: qemu-arm-static     },
+          { name: ARM64,    xcc_pkg: gcc-aarch64-linux-gnu,     xcc: aarch64-linux-gnu-gcc,     xemu_pkg: qemu-system-arm,    xemu: qemu-aarch64-static },
+          { name: PPC,      xcc_pkg: gcc-powerpc-linux-gnu,     xcc: powerpc-linux-gnu-gcc,     xemu_pkg: qemu-system-ppc,    xemu: qemu-ppc-static     },
+          { name: PPC64LE,  xcc_pkg: gcc-powerpc64le-linux-gnu, xcc: powerpc64le-linux-gnu-gcc, xemu_pkg: qemu-system-ppc,    xemu: qemu-ppc64le-static },
+          { name: S390X,    xcc_pkg: gcc-s390x-linux-gnu,       xcc: s390x-linux-gnu-gcc,       xemu_pkg: qemu-system-s390x,  xemu: qemu-s390x-static   },
+          { name: MIPS,     xcc_pkg: gcc-mips-linux-gnu,        xcc: mips-linux-gnu-gcc,        xemu_pkg: qemu-system-mips,   xemu: qemu-mips-static    },
+          { name: M68K,     xcc_pkg: gcc-m68k-linux-gnu,        xcc: m68k-linux-gnu-gcc,        xemu_pkg: qemu-system-m68k,   xemu: qemu-m68k-static    },
+        ]
+    env:                        # Set environment variables
+      XCC: ${{ matrix.xcc }}
+      XEMU: ${{ matrix.xemu }}
+    steps:
+    - uses: actions/checkout@v2 # https://github.com/actions/checkout
+    - name: apt update & install
+      run: |
+        sudo apt-get update
+        sudo apt-get install gcc-multilib g++-multilib qemu-utils qemu-user-static
+        sudo apt-get install ${{ matrix.xcc_pkg }} ${{ matrix.xemu_pkg }}
+    - name: Environment info
+      run: |
+        echo && which $XCC
+        echo && $XCC --version
+        echo && $XCC -v  # Show built-in specs
+        echo && which $XEMU
+        echo && $XEMU --version
+    - name: ARM
+      if: ${{ matrix.name == 'ARM' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: ARM64
+      if: ${{ matrix.name == 'ARM64' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: PPC
+      if: ${{ matrix.name == 'PPC' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: PPC64LE
+      if: ${{ matrix.name == 'PPC64LE' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: S390X
+      if: ${{ matrix.name == 'S390X' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: MIPS
+      if: ${{ matrix.name == 'MIPS' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+    - name: M68K
+      if: ${{ matrix.name == 'M68K' }}
+      run: |
+        LDFLAGS="-static" CC=$XCC QEMU_SYS=$XEMU make clean check
+
+  mingw-short-test:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include: [
+          { compiler: gcc, platform: x64, script: "CFLAGS=-Werror make -j allzstd DEBUGLEVEL=2"},
+          { compiler: gcc, platform: x86, script: "CFLAGS=-Werror make -j allzstd"},
+          { compiler: clang, platform: x64, script: "CFLAGS='--target=x86_64-w64-mingw32 -Werror -Wconversion -Wno-sign-conversion' make -j allzstd V=1"},
+        ]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Mingw short test
+      run: |
+        ECHO "Building ${{matrix.compiler}} ${{matrix.platform}}"
+        $env:PATH_ORIGINAL = $env:PATH
+        $env:PATH_MINGW32 = "C:\msys64\mingw32\bin"
+        $env:PATH_MINGW64 = "C:\msys64\mingw64\bin"
+        COPY C:\msys64\usr\bin\make.exe C:\msys64\mingw32\bin\make.exe
+        COPY C:\msys64\usr\bin\make.exe C:\msys64\mingw64\bin\make.exe
+        IF ("${{matrix.platform}}" -eq "x64")
+        {
+            $env:PATH = $env:PATH_MINGW64 + ";" + $env:PATH_ORIGINAL
+        }
+        ELSEIF ("${{matrix.platform}}" -eq "x86")
+        {
+            $env:PATH = $env:PATH_MINGW32 + ";" + $env:PATH_ORIGINAL
+        }
+        make -v
+        sh -c "${{matrix.compiler}} -v"
+        $env:CC = "${{matrix.compiler}}"
+        sh -c "${{matrix.script}}"
+        ECHO "Testing ${{matrix.compiler}} ${{matrix.platform}}"
+        make clean
+        make check
+
+
+  visual-runtime-tests:
+    runs-on: windows-latest
+    strategy:
+      matrix:
+        platform: [x64, Win32]
+        configuration: [Release]
+    steps:
+    - uses: actions/checkout@v2
+    - name: Add MSBuild to PATH
+      uses: microsoft/setup-msbuild@v1.0.2
+    - name: Build and run tests
+      working-directory: ${{env.GITHUB_WORKSPACE}}
+      env:
+        ZSTD_BIN: ./zstd.exe
+        DATAGEN_BIN: ./datagen.exe
+      # See https://docs.microsoft.com/visualstudio/msbuild/msbuild-command-line-reference
+      run: |
+        msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v142 /t:Clean,Build /p:Platform=${{matrix.platform}} /p:Configuration=${{matrix.configuration}}
+        COPY build\VS2010\bin\${{matrix.platform}}_${{matrix.configuration}}\*.exe tests\
+        CD tests
+        sh -e playTests.sh
+        DIR
+        .\fuzzer.exe -T2m
+
+  intel-cet-compatibility:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Build Zstd
+      run: |
+        make -j zstd V=1
+        readelf -n zstd
+    - name: Get Intel SDE
+      run: |
+        curl -LO https://downloadmirror.intel.com/684899/sde-external-9.0.0-2021-11-07-lin.tar.xz
+        tar xJvf sde-external-9.0.0-2021-11-07-lin.tar.xz
+    - name: Configure Permissions
+      run: |
+        echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope
+    - name: Run Under SDE
+      run: |
+        sde-external-9.0.0-2021-11-07-lin/sde -cet -cet-raise 0 -cet-endbr-exe -cet-stderr -cet-abort -- ./zstd -b3
+
+
+
+# This test currently fails on Github Actions specifically.
+# Possible reason : TTY emulation.
+# Note that the same test works fine locally and on travisCI.
+# This will have to be fixed before transferring the test to GA.
+#  versions-compatibility:
+#    runs-on: ubuntu-latest
+#    steps:
+#    - uses: actions/checkout@v2
+#    - name: Versions Compatibility Test
+#      run: |
+#        make -C tests versionsTest
+
+
+# For reference : icc tests
+# icc tests are currently failing on Github Actions, likely to issues during installation stage
+# To be fixed later
+#
+#  icc:
+#    name: icc-check
+#    runs-on: ubuntu-latest
+#    steps:
+#    - name: install icc
+#      run: |
+#        export DEBIAN_FRONTEND=noninteractive
+#        sudo apt-get -qqq update
+#        sudo apt-get install -y wget build-essential pkg-config cmake ca-certificates gnupg
+#        sudo wget https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS-2023.PUB
+#        sudo apt-key add GPG-PUB-KEY-INTEL-SW-PRODUCTS-2023.PUB
+#        sudo add-apt-repository "deb https://apt.repos.intel.com/oneapi all main"
+#        sudo apt-get update
+#        sudo apt-get install -y intel-basekit intel-hpckit
+#    - uses: actions/checkout@v2
+#    - name: make check
+#      run: |
+#        make CC=/opt/intel/oneapi/compiler/latest/linux/bin/intel64/icc check

.github/workflows/generic-dev.yml

@@ -1,225 +0,0 @@
-name: generic-dev
-
-on:
-  pull_request:
-    branches: [ dev, release, actionsTest ]
-
-jobs:
-
-# Dev PR jobs that still have to be migrated from travis
-#
-# versionTag (only on release tags)
-# valgrindTest (keeps failing for some reason. need investigation)
-# staticAnalyze (need trusty so need self-hosted)
-# pcc-fuzz: (need trusty so need self-hosted)
-# min-decomp-macros (flakey)
-#
-# setting up self-hosted is pretty straightforward, but
-# I need admins permissions to the repo for that it looks like
-# So I'm tabling that for now
-#
-# The release branch exclusive jobs will be in a separate
-# workflow file (the osx tests and meson build that is)
-
-  benchmarking:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: make benchmarking
-      run: make benchmarking
-
-  test:
-    runs-on: ubuntu-latest
-    env:
-      DEVNULLRIGHTS: 1
-      READFROMBLOCKDEVICE: 1
-    steps:
-    - uses: actions/checkout@v2
-    - name: make test
-      run: make test
-
-  check-32bit: # designed to catch https://github.com/facebook/zstd/issues/2428
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: make check on 32-bit
-      run: |
-        sudo apt update
-        APT_PACKAGES="gcc-multilib" make apt-install
-        CFLAGS="-m32 -O1 -fstack-protector" make check V=1
-
-  gcc-7-libzstd:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: gcc-7 + libzstdmt compilation
-      run: |
-        make gcc7install
-        CC=gcc-7 CFLAGS=-Werror make -j all
-        make clean
-        LDFLAGS=-Wl,--no-undefined make -C lib libzstd-mt
-
-    # candidate test (to check) : underlink test
-    # LDFLAGS=-Wl,--no-undefined : will make the linker fail if dll is underlinked
-
-  gcc-8-asan-ubsan-testzstd:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: gcc-8 + ASan + UBSan + Test Zstd
-      run: |
-        make gcc8install
-        CC=gcc-8 CFLAGS="-Werror" make -j all
-        make clean
-        CC=gcc-8 make -j uasan-test-zstd </dev/null V=1
-
-  gcc-asan-ubsan-testzstd-32bit:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: ASan + UBSan + Test Zstd, 32bit mode
-      run: |
-        make libc6install
-        CFLAGS="-Werror -m32" make -j all32
-        make clean
-        make -j uasan-test-zstd32 V=1
-
-  clang-msan-testzstd:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: clang + MSan + Test Zstd
-      run: |
-        sudo apt-get update
-        sudo apt-get install clang
-        CC=clang make msan-test-zstd HAVE_ZLIB=0 HAVE_LZ4=0 HAVE_LZMA=0 V=1
-
-    # Note : external libraries must be turned off when using MSAN tests,
-    # because they are not msan-instrumented,
-    # so any data coming from these libraries is always considered "uninitialized"
-
-  cmake-build-and-test-check:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: cmake build and test check
-      run: |
-        FUZZERTEST=-T1mn ZSTREAM_TESTTIME=-T1mn make cmakebuild
-        cp -r ./ "../zstd source"
-        cd "../zstd source"
-        FUZZERTEST=-T1mn ZSTREAM_TESTTIME=-T1mn make cmakebuild
-
-  gcc-8-asan-ubsan-fuzz:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: gcc-8 + ASan + UBSan + Fuzz Test
-      run: |
-        make gcc8install
-        CC=gcc-8 FUZZER_FLAGS="--long-tests" make clean uasan-fuzztest
-
-  gcc-asan-ubsan-fuzz32:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: ASan + UBSan + Fuzz Test 32bit
-      run: |
-        make libc6install
-        CFLAGS="-O2 -m32" FUZZER_FLAGS="--long-tests" make uasan-fuzztest
-
-  clang-msan-fuzz:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: clang + MSan + Fuzz Test
-      run: |
-        sudo apt-get update
-        sudo apt-get install clang
-        CC=clang FUZZER_FLAGS="--long-tests" make clean msan-fuzztest
-
-  asan-ubsan-msan-regression:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: ASan + UBSan + MSan + Regression Test
-      run: |
-        make -j uasanregressiontest
-        make clean
-        make -j msanregressiontest
-
-  cpp-gnu90-c99-compatibility:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: C++, gnu90 and c99 compatibility
-      run: |
-        make cxxtest
-        make clean
-        make gnu90build
-        make clean
-        make c99build
-        make clean
-        make travis-install   # just ensures `make install` works
-
-  mingw-cross-compilation:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: mingw cross-compilation
-      run: |
-        # sudo update-alternatives --set x86_64-w64-mingw32-g++ /usr/bin/x86_64-w64-mingw32-g++-posix; (doesn't work)
-        sudo apt-get install gcc-mingw-w64
-        CC=x86_64-w64-mingw32-gcc CXX=x86_64-w64-mingw32-g++ CFLAGS="-Werror -O1" make zstd
-
-# TODO: Broken test - fix and uncomment
-#  armbuild:
-#    runs-on: ubuntu-16.04 # doesn't work on latest
-#    steps:
-#    - uses: actions/checkout@v2
-#    - name: ARM Build Test
-#      run: |
-#        make arminstall
-#        make armbuild
-
-# TODO: Broken test - fix and uncomment
-#  armfuzz:
-#    runs-on: ubuntu-16.04 # doesn't work on latest
-#    steps:
-#    - uses: actions/checkout@v2
-#    - name: Qemu ARM emulation + Fuzz Test
-#      run: |
-#        make arminstall
-#        make armfuzz
-
-  bourne-shell:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: Bourne shell compatibility (shellcheck)
-      run: |
-        wget https://github.com/koalaman/shellcheck/releases/download/v0.7.1/shellcheck-v0.7.1.linux.x86_64.tar.xz
-        tar -xf shellcheck-v0.7.1.linux.x86_64.tar.xz
-        shellcheck-v0.7.1/shellcheck --shell=sh --severity=warning --exclude=SC2010 tests/playTests.sh
-
-# For reference : icc tests
-# icc tests are currently failing on Github Actions, likely to issues during installation stage
-# To be fixed later
-#
-#  icc:
-#    name: icc-check
-#    runs-on: ubuntu-latest
-#    steps:
-#    - name: install icc
-#      run: |
-#        export DEBIAN_FRONTEND=noninteractive
-#        sudo apt-get -qqq update
-#        sudo apt-get install -y wget build-essential pkg-config cmake ca-certificates gnupg
-#        sudo wget https://apt.repos.intel.com/intel-gpg-keys/GPG-PUB-KEY-INTEL-SW-PRODUCTS-2023.PUB
-#        sudo apt-key add GPG-PUB-KEY-INTEL-SW-PRODUCTS-2023.PUB
-#        sudo add-apt-repository "deb https://apt.repos.intel.com/oneapi all main"
-#        sudo apt-get update
-#        sudo apt-get install -y intel-basekit intel-hpckit
-#    - uses: actions/checkout@v2
-#    - name: make check
-#      run: |
-#        make CC=/opt/intel/oneapi/compiler/latest/linux/bin/intel64/icc check

.github/workflows/generic-release.yml

@@ -1,59 +0,0 @@
-name: generic-release
-
-on:
-  pull_request:
-    # This will eventually only be for pushes to release
-    # but for dogfooding purposes, I'm running it even
-    # on dev pushes
-    branches: [ dev, release, actionsTest ]
-
-jobs:
-  # missing jobs
-  #
-  # ppc64le + fuzz test
-  # Qemu PPC64 + Fuzz test
-  # Qemu aarch64 + Fuzz Test (on Xenial)
-  # versions comp
-  # meson test
-
-  osx:
-    runs-on: macos-10.15
-    steps:
-    - uses: actions/checkout@v2
-    - name: OS-X
-      run: |
-        make test
-        # make -c lib all (need to fix. not working right now)
-
-  tsan:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: thread sanitizer
-      run: |
-        CC=clang make tsan-test-zstream
-        CC=clang make tsan-fuzztest
-
-  zlib-wrapper:
-    runs-on: ubuntu-16.04
-    steps:
-    - uses: actions/checkout@v2
-    - name: zlib wrapper test
-      run: |
-        make valgrindinstall
-        make -C zlibWrapper test
-        make -C zlibWrapper valgrindTest
-
-  lz4-threadpool-partial-libs:
-    runs-on: ubuntu-16.04
-    steps:
-    - uses: actions/checkout@v2
-    - name: LZ4, thread pool, and partial libs testslib wrapper test
-      run: |
-        make lz4install
-        make -C tests test-lz4
-        make check < /dev/null | tee   # mess with lz4 console detection
-        make clean
-        make -C tests test-pool
-        make clean
-        bash tests/libzstd_partial_builds.sh

.github/workflows/linux-kernel.yml

@@ -1,13 +0,0 @@
-name: linux-kernel
-
-on:
-  pull_request:
-    branches: [ dev, release, actionsTest ]
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - name: Create linux kernel library + build + test
-      run: make -C contrib/linux-kernel test CFLAGS="-Werror -Wunused-const-variable -Wunused-but-set-variable"

.github/workflows/main.yml

@@ -1,30 +0,0 @@
-name: CIFuzz
-on: [pull_request]
-jobs:
-  Fuzzing:
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        sanitizer: [address, undefined]
-    steps:
-    - name: Build Fuzzers (${{ matrix.sanitizer }})
-      id: build
-      uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
-      with:
-        oss-fuzz-project-name: 'zstd'
-        dry-run: false
-        sanitizer: ${{ matrix.sanitizer }}
-    - name: Run Fuzzers (${{ matrix.sanitizer }})
-      uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
-      with:
-        oss-fuzz-project-name: 'zstd'
-        fuzz-seconds: 600
-        dry-run: false
-        sanitizer: ${{ matrix.sanitizer }}
-    - name: Upload Crash
-      uses: actions/upload-artifact@v1
-      if: failure() && steps.build.outcome == 'success'
-      with:
-        name: ${{ matrix.sanitizer }}-artifacts
-        path: ./out/artifacts

.github/workflows/publish-release-artifacts.yml

@@ -3,7 +3,7 @@ name: publish-release-artifacts
 on:
   release:
     types:
-      - created
+      - published
 
 jobs:
   publish-release-artifacts:

.gitignore

@@ -29,6 +29,7 @@ dictionary
 NUL
 
 # Build artefacts
+contrib/linux-kernel/linux/
 projects/
 bin/
 .buckd/

.travis.yml

@@ -1,5 +1,6 @@
-# Medium Tests: Run on all commits/PRs to dev branch
-
+# Travis CI is used to test platforms that github-actions currently doesn't support
+# without either self-hosting or some finnicky work-around. Also, some tests
+# are troublesome to migrate since GH Actions runs tests not in a tty.
 language: c
 
 git:
@@ -18,47 +19,48 @@ addons:
 
 env:
   global:
-    - FUZZERTEST=-T2mn
-      ZSTREAM_TESTTIME=-T2mn
+    - FUZZERTEST=-T1mn
+      ZSTREAM_TESTTIME=-T1mn
       DECODECORPUS_TESTTIME=-T1mn
 
-
 matrix:
   fast_finish: true
   include:
+    - name: S390X (big endian) + Fuzz test
+      dist: trusty
+      arch: s390x
+      script:
+        - FUZZER_FLAGS=--no-big-tests make -C tests fuzztest
+
+    - name: S390X (big endian) + Fuzz test + no intrinsics
+      dist: trusty
+      arch: s390x
+      script:
+        - MOREFLAGS="-DZSTD_NO_INTRINSICS" FUZZER_FLAGS=--no-big-tests make -C tests fuzztest
+
     - name: arm64    # ~2.5 mn
       os: linux
       arch: arm64
       script:
         - make check
 
-    - name: Minimal Decompressor Macros    # ~5mn
+    - name: arm64fuzz
+      os: linux
+      arch: arm64
       script:
-        - make clean && make -j all ZSTD_LIB_MINIFY=1 MOREFLAGS="-Werror"
-        - make clean && make check ZSTD_LIB_MINIFY=1 MOREFLAGS="-Werror"
-        - make clean && make -j all MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X1 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT"
-        - make clean && make check MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X1 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT"
-        - make clean && make -j all MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X2 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG"
-        - make clean && make check MOREFLAGS="-Werror -DHUF_FORCE_DECOMPRESS_X2 -DZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG"
-        - make clean && make -j all MOREFLAGS="-Werror -DZSTD_NO_INLINE -DZSTD_STRIP_ERROR_STRINGS"
-        - make clean && make check MOREFLAGS="-Werror -DZSTD_NO_INLINE -DZSTD_STRIP_ERROR_STRINGS"
+        - make -C tests fuzztest
 
-    - name: static analyzer scanbuild    # ~26mn
+    # TODO: migrate to GH Actions once newest clang staticanalyze warnings are fixed
+    - name: static analyzer scanbuild    # ~8mn
       dist: trusty  # note : it's important to pin down a version of static analyzer, since different versions report different false positives
       script:
         - make staticAnalyze
 
-    - name: Valgrind + Fuzz Test Stack Mode    # ~ 7mn
+    # GH actions can't run this command on OS-X, non-tty issues
+    - name: OS-X make all lib
+      os: osx
       script:
-        - make valgrindinstall
-        - make -C tests clean valgrindTest
-        - make clean
-        - make -C tests test-fuzzer-stackmode
-
-    - name: Qemu ARM emulation + Fuzz Test    # ~13.5mn
-      script:
-        - make arminstall
-        - make armfuzz
+        - make -C lib all
 
     # Introduced to check compat with old toolchains, to prevent e.g. #1872
     - name: ARM Build Test (on Trusty)
@@ -67,65 +69,31 @@ matrix:
         - make arminstall
         - make armbuild
 
-    - name: Qemu PPC + Fuzz Test    # ~13mn
-      dist: trusty   # it seems ppc cross-compilation fails on "current"
-      script:
-        - make ppcinstall
-        - make ppcfuzz
-
-    # check release number (release only)
+    # check release number (release/new tag only)
     - name: Tag-Specific Test
       if: tag =~ ^v[0-9]\.[0-9]
       script:
         - make -C tests checkTag
         - tests/checkTag "$TRAVIS_BRANCH"
 
-    # tests for release branch and cron job only
-    - name: OS-X    # ~13mn
-      if: branch = release
-      os: osx
+    - name: PPC64LE + Fuzz test  # ~13mn
+      arch: ppc64le
+      env:
+        - FUZZER_FLAGS=--no-big-tests
+        - MOREFLAGS="-static"
       script:
-        - make test
-        - make -C lib all
+        - cat /proc/cpuinfo
+        - make -C tests fuzztest
 
-    - name: Versions Compatibility Test   # 11.5mn
-      if: branch = release
+    # This test currently fails on GA specifically, for no obvious reason
+    # (it works fine on travisCI, and on local test platforms).
+    - name: Versions Compatibility Test   # ~6mn
       script:
         - make -C tests versionsTest
 
-    - name: thread sanitizer   # ~29mn
-      if: branch = release
-      script:
-        - make clang38install
-        - CC=clang-3.8 make tsan-test-zstream
-        - CC=clang-3.8 make tsan-fuzztest
-
-    - name: PPC64LE + Fuzz test  # ~13mn
-      if: branch = release
-      arch: ppc64le
-      script:
-        - cat /proc/cpuinfo
-        - make test
-
-    - name: Qemu PPC64 + Fuzz test  # ~13mn, presumed Big-Endian (?)
-      dist: trusty  # note : PPC64 cross-compilation for Qemu tests seems broken on Xenial
-      if: branch = release
-      script:
-        - make ppcinstall
-        - make ppc64fuzz
-
-    # note : we already have aarch64 tests on hardware
-    - name: Qemu aarch64 + Fuzz Test (on Xenial)    # ~14mn
-      if: branch = release
-      dist: xenial
-      script:
-        - make arminstall
-        - make aarch64fuzz
-
     # meson dedicated test
     - name: Xenial (Meson + clang)    # ~15mn
-      if: branch = release
-      dist: xenial
+      dist: bionic
       language: cpp
       compiler: clang
       install:

CHANGELOG

@@ -1,3 +1,26 @@
+v1.5.2 (Jan, 2022)
+perf: Regain Minimal memset()-ing During Reuse of Compression Contexts (@Cyan4973, #2969)
+build: Build Zstd with `noexecstack` on All Architectures (@felixhandte, #2964)
+doc: Clarify Licensing (@terrelln, #2981)
+
+v1.5.1 (Dec, 2021)
+perf: rebalanced compression levels, to better match the intended speed/level curve, by @senhuang42
+perf: faster huffman decoder, using x64 assembly, by @terrelln
+perf: slightly faster high speed modes (strategies fast & dfast), by @felixhandte
+perf: improved binary size and faster compilation times, by @terrelln
+perf: new row64 mode, used notably in level 12, by @senhuang42
+perf: faster mid-level compression speed in presence of highly repetitive patterns, by @senhuang42
+perf: minor compression ratio improvements for small data at high levels, by @cyan4973
+perf: reduced stack usage (mostly useful for Linux Kernel), by @terrelln
+perf: faster compression speed on incompressible data, by @bindhvo
+perf: on-demand reduced ZSTD_DCtx state size, using build macro ZSTD_DECODER_INTERNAL_BUFFER, at a small cost of performance, by @bindhvo
+build: allows hiding static symbols in the dynamic library, using build macro, by @skitt
+build: support for m68k (Motorola 68000's), by @cyan4973
+build: improved AIX support, by @Helflym
+build: improved meson unofficial build, by @eli-schwartz
+cli : custom memory limit when training dictionary (#2925), by @embg
+cli : report advanced parameters information when compressing in very verbose mode (``-vv`), by @Svetlitski-FB
+
 v1.5.0  (May 11, 2021)
 api: Various functions promoted from experimental to stable API: (#2579-2581, @senhuang42)
   `ZSTD_defaultCLevel()`

CONTRIBUTING.md

@@ -47,7 +47,7 @@ Our contribution process works in three main stages:
     * Topic and development:
         * Make a new branch on your fork about the topic you're developing for
         ```
-        # branch names should be consise but sufficiently informative
+        # branch names should be concise but sufficiently informative
         git checkout -b <branch-name>
         git push origin <branch-name>
         ```
@@ -68,8 +68,8 @@ Our contribution process works in three main stages:
             ```
 2. Code Review and CI tests
     * Ensure CI tests pass:
-        * Before sharing anything to the community, make sure that all CI tests pass on your local fork.
-        See our section on setting up your CI environment for more information on how to do this.
+        * Before sharing anything to the community, create a pull request in your own fork against the dev branch
+        and make sure that all GitHub Actions CI tests pass. See the Continuous Integration section below for more information.
         * Ensure that static analysis passes on your development machine. See the Static Analysis section
         below to see how to do this.
     * Create a pull request:
@@ -104,7 +104,7 @@ Our contribution process works in three main stages:
         issue at hand, then please indicate this by requesting that an issue be closed by commenting.
         * Just because your changes have been merged does not mean the topic or larger issue is complete. Remember
         that the change must make it to an official zstd release for it to be meaningful. We recommend
-        that contributers track the activity on their pull request and corresponding issue(s) page(s) until
+        that contributors track the activity on their pull request and corresponding issue(s) page(s) until
         their change makes it to the next release of zstd. Users will often discover bugs in your code or
         suggest ways to refine and improve your initial changes even after the pull request is merged.
 
@@ -140,6 +140,42 @@ It can be useful to look at additional static analyzers once in a while (and we
 
 This is different from running a static analyzer once in a while, looking at the output, and __cherry picking__ a few warnings that seem helpful, either because they detected a genuine risk of bug, or because it helps expressing the code in a way which is more readable or more difficult to misuse. These kind of reports can be useful, and are accepted.
 
+## Continuous Integration
+CI tests run every time a pull request (PR) is created or updated. The exact tests
+that get run will depend on the destination branch you specify. Some tests take
+longer to run than others. Currently, our CI is set up to run a short
+series of tests when creating a PR to the dev branch and a longer series of tests
+when creating a PR to the release branch. You can look in the configuration files
+of the respective CI platform for more information on what gets run when.
+
+Most people will just want to create a PR with the destination set to their local dev
+branch of zstd. You can then find the status of the tests on the PR's page. You can also
+re-run tests and cancel running tests from the PR page or from the respective CI's dashboard.
+
+Almost all of zstd's CI runs on GitHub Actions (configured at `.github/workflows`), which will automatically run on PRs to your
+own fork. A small number of tests run on other services (e.g. Travis CI, Circle CI, Appveyor).
+These require work to set up on your local fork, and (at least for Travis CI) cost money.
+Therefore, if the PR on your local fork passes GitHub Actions, feel free to submit a PR
+against the main repo.
+
+### Third-party CI
+A small number of tests cannot run on GitHub Actions, or have yet to be migrated.
+For these, we use a variety of third-party services (listed below). It is not necessary to set
+these up on your fork in order to contribute to zstd; however, we do link to instructions for those
+who want earlier signal.
+
+| Service   | Purpose                                                                                                    | Setup Links                                                                                                                                            | Config Path            |
+|-----------|------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------|------------------------|
+| Travis CI | Used for testing on non-x86 architectures such as PowerPC                                                  | https://docs.travis-ci.com/user/tutorial/#to-get-started-with-travis-ci-using-github <br> https://github.com/marketplace/travis-ci                     | `.travis.yml`          |
+| AppVeyor  | Used for some Windows testing (e.g. cygwin, mingw)                                                         | https://www.appveyor.com/blog/2018/10/02/github-apps-integration/ <br> https://github.com/marketplace/appveyor                                         | `appveyor.yml`         |
+| Cirrus CI | Used for testing on FreeBSD                                                                                | https://github.com/marketplace/cirrus-ci/                                                                                                              | `.cirrus.yml`          |
+| Circle CI | Historically was used to provide faster signal,<br/> but we may be able to migrate these to Github Actions | https://circleci.com/docs/2.0/getting-started/#setting-up-circleci <br> https://youtu.be/Js3hMUsSZ2c <br> https://circleci.com/docs/2.0/enable-checks/ | `.circleci/config.yml` |
+
+Note: the instructions linked above mostly cover how to set up a repository with CI from scratch. 
+The general idea should be the same for setting up CI on your fork of zstd, but you may have to 
+follow slightly different steps. In particular, please ignore any instructions related to setting up
+config files (since zstd already has configs for each of these services).
+
 ## Performance
 Performance is extremely important for zstd and we only merge pull requests whose performance
 landscape and corresponding trade-offs have been adequately analyzed, reproduced, and presented.
@@ -270,15 +306,15 @@ for level 1 compression on Zstd. Typically this means, you have identified a sec
 code that you think can be made to run faster.
 
 The first thing you will want to do is make sure that the piece of code is actually taking up
-a notable amount of time to run. It is usually not worth optimzing something which accounts for less than
+a notable amount of time to run. It is usually not worth optimizing something which accounts for less than
 0.0001% of the total running time. Luckily, there are tools to help with this.
 Profilers will let you see how much time your code spends inside a particular function.
-If your target code snippit is only part of a function, it might be worth trying to
-isolate that snippit by moving it to its own function (this is usually not necessary but
+If your target code snippet is only part of a function, it might be worth trying to
+isolate that snippet by moving it to its own function (this is usually not necessary but
 might be).
 
-Most profilers (including the profilers dicusssed below) will generate a call graph of
-functions for you. Your goal will be to find your function of interest in this call grapch
+Most profilers (including the profilers discussed below) will generate a call graph of
+functions for you. Your goal will be to find your function of interest in this call graph
 and then inspect the time spent inside of it. You might also want to to look at the
 annotated assembly which most profilers will provide you with.
 
@@ -301,16 +337,16 @@ $ zstd -b1 -i5 <my-data> # this will run for 5 seconds
 5. Once you run your benchmarking script, switch back over to instruments and attach your
 process to the time profiler. You can do this by:
     * Clicking on the `All Processes` drop down in the top left of the toolbar.
-    * Selecting your process from the dropdown. In my case, it is just going to be labled
+    * Selecting your process from the dropdown. In my case, it is just going to be labeled
     `zstd`
     * Hitting the bright red record circle button on the top left of the toolbar
-6. You profiler will now start collecting metrics from your bencharking script. Once
+6. You profiler will now start collecting metrics from your benchmarking script. Once
 you think you have collected enough samples (usually this is the case after 3 seconds of
 recording), stop your profiler.
 7. Make sure that in toolbar of the bottom window, `profile` is selected.
 8. You should be able to see your call graph.
     * If you don't see the call graph or an incomplete call graph, make sure you have compiled
-    zstd and your benchmarking scripg using debug flags. On mac and linux, this just means
+    zstd and your benchmarking script using debug flags. On mac and linux, this just means
     you will have to supply the `-g` flag alone with your build script. You might also
     have to provide the `-fno-omit-frame-pointer` flag
 9. Dig down the graph to find your function call and then inspect it by double clicking
@@ -329,7 +365,7 @@ Some general notes on perf:
 counter statistics. Perf uses a high resolution timer and this is likely one
 of the first things your team will run when assessing your PR.
 * Perf has a long list of hardware counters that can be viewed with `perf --list`.
-When measuring optimizations, something worth trying is to make sure the handware
+When measuring optimizations, something worth trying is to make sure the hardware
 counters you expect to be impacted by your change are in fact being so. For example,
 if you expect the L1 cache misses to decrease with your change, you can look at the
 counter `L1-dcache-load-misses`
@@ -339,57 +375,6 @@ counter `L1-dcache-load-misses`
 
 TODO
 
-
-## Setting up continuous integration (CI) on your fork
-Zstd uses a number of different continuous integration (CI) tools to ensure that new changes
-are well tested before they make it to an official release. Specifically, we use the platforms
-travis-ci, circle-ci, and appveyor.
-
-Changes cannot be merged into the main dev branch unless they pass all of our CI tests.
-The easiest way to run these CI tests on your own before submitting a PR to our dev branch
-is to configure your personal fork of zstd with each of the CI platforms. Below, you'll find
-instructions for doing this.
-
-### travis-ci
-Follow these steps to link travis-ci with your github fork of zstd
-
-1. Make sure you are logged into your github account
-2. Go to https://travis-ci.org/
-3. Click 'Sign in with Github' on the top right
-4. Click 'Authorize travis-ci'
-5. Click 'Activate all repositories using Github Apps'
-6. Select 'Only select repositories' and select your fork of zstd from the drop down
-7. Click 'Approve and Install'
-8. Click 'Sign in with Github' again. This time, it will be for travis-pro (which will let you view your tests on the web dashboard)
-9. Click 'Authorize travis-pro'
-10. You should have travis set up on your fork now.
-
-### circle-ci
-TODO
-
-### appveyor
-Follow these steps to link circle-ci with your girhub fork of zstd
-
-1. Make sure you are logged into your github account
-2. Go to https://www.appveyor.com/
-3. Click 'Sign in' on the top right
-4. Select 'Github' on the left panel
-5. Click 'Authorize appveyor'
-6. You might be asked to select which repositories you want to give appveyor permission to. Select your fork of zstd if you're prompted
-7. You should have appveyor set up on your fork now.
-
-### General notes on CI
-CI tests run every time a pull request (PR) is created or updated. The exact tests
-that get run will depend on the destination branch you specify. Some tests take
-longer to run than others. Currently, our CI is set up to run a short
-series of tests when creating a PR to the dev branch and a longer series of tests
-when creating a PR to the release branch. You can look in the configuration files
-of the respective CI platform for more information on what gets run when.
-
-Most people will just want to create a PR with the destination set to their local dev
-branch of zstd. You can then find the status of the tests on the PR's page. You can also
-re-run tests and cancel running tests from the PR page or from the respective CI's dashboard.
-
 ## Issues
 We use GitHub issues to track public bugs. Please ensure your description is
 clear and has sufficient instructions to be able to reproduce the issue.

Makefile

@@ -29,6 +29,7 @@ VOID = /dev/null
 # fail on other tested distros (ubuntu, debian) even
 # without manually specifying the TARGET_SYSTEM.
 TARGET_SYSTEM ?= $(OS)
+CP ?= cp
 
 ifneq (,$(filter Windows%,$(TARGET_SYSTEM)))
   EXT =.exe
@@ -69,7 +70,7 @@ zstd zstd-release:
 .PHONY: zstdmt
 zstdmt:
 	$(Q)$(MAKE) -C $(PRGDIR) $@
-	$(Q)cp $(PRGDIR)/zstd$(EXT) ./zstdmt$(EXT)
+	$(Q)$(CP) $(PRGDIR)/zstd$(EXT) ./zstdmt$(EXT)
 
 .PHONY: zlibwrapper
 zlibwrapper: lib
@@ -148,10 +149,12 @@ clean:
 #------------------------------------------------------------------------------
 # make install is validated only for Linux, macOS, Hurd and some BSD targets
 #------------------------------------------------------------------------------
-ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD DragonFly NetBSD MSYS_NT Haiku))
+ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD DragonFly NetBSD MSYS_NT Haiku AIX))
 
 HOST_OS = POSIX
 
+MKDIR ?= mkdir -p
+
 HAVE_COLORNEVER = $(shell echo a | egrep --color=never a > /dev/null 2> /dev/null && echo 1 || echo 0)
 EGREP_OPTIONS ?=
 ifeq ($HAVE_COLORNEVER, 1)
@@ -217,7 +220,7 @@ armbuild: clean
 	CC=arm-linux-gnueabi-gcc CFLAGS="-Werror" $(MAKE) allzstd
 
 aarch64build: clean
-	CC=aarch64-linux-gnu-gcc CFLAGS="-Werror" $(MAKE) allzstd
+	CC=aarch64-linux-gnu-gcc CFLAGS="-Werror -O0" $(MAKE) allzstd
 
 ppcbuild: clean
 	CC=powerpc-linux-gnu-gcc CFLAGS="-m32 -Wno-attributes -Werror" $(MAKE) -j allzstd
@@ -284,6 +287,22 @@ uasanregressiontest:
 msanregressiontest:
 	$(MAKE) -C $(FUZZDIR) regressiontest CC=clang CXX=clang++ CFLAGS="-O3 -fsanitize=memory" CXXFLAGS="-O3 -fsanitize=memory"
 
+update_regressionResults : REGRESS_RESULTS_DIR := /tmp/regress_results_dir/
+update_regressionResults:
+	$(MAKE) -C programs zstd
+	$(MAKE) -C tests/regression test
+	$(RM) -rf $(REGRESS_RESULTS_DIR)
+	$(MKDIR) $(REGRESS_RESULTS_DIR)
+	./tests/regression/test                         \
+        --cache  tests/regression/cache             \
+        --output $(REGRESS_RESULTS_DIR)/results.csv \
+        --zstd   programs/zstd
+	echo "Showing results differences"
+	! diff tests/regression/results.csv $(REGRESS_RESULTS_DIR)/results.csv
+	echo "Updating results.csv"
+	$(CP) $(REGRESS_RESULTS_DIR)/results.csv tests/regression/results.csv
+
+
 # run UBsan with -fsanitize-recover=pointer-overflow
 # this only works with recent compilers such as gcc 8+
 usan: clean
@@ -372,7 +391,7 @@ ifneq (,$(filter $(HOST_OS),MSYS POSIX))
 cmakebuild:
 	cmake --version
 	$(RM) -r $(BUILDIR)/cmake/build
-	mkdir $(BUILDIR)/cmake/build
+	$(MKDIR) $(BUILDIR)/cmake/build
 	cd $(BUILDIR)/cmake/build; cmake -DCMAKE_INSTALL_PREFIX:PATH=~/install_test_dir $(CMAKE_PARAMS) ..
 	$(MAKE) -C $(BUILDIR)/cmake/build -j4;
 	$(MAKE) -C $(BUILDIR)/cmake/build install;
@@ -381,23 +400,23 @@ cmakebuild:
 
 c89build: clean
 	$(CC) -v
-	CFLAGS="-std=c89 -Werror" $(MAKE) allmost  # will fail, due to missing support for `long long`
+	CFLAGS="-std=c89 -Werror -O0" $(MAKE) allmost  # will fail, due to missing support for `long long`
 
 gnu90build: clean
 	$(CC) -v
-	CFLAGS="-std=gnu90 -Werror" $(MAKE) allmost
+	CFLAGS="-std=gnu90 -Werror -O0" $(MAKE) allmost
 
 c99build: clean
 	$(CC) -v
-	CFLAGS="-std=c99 -Werror" $(MAKE) allmost
+	CFLAGS="-std=c99 -Werror -O0" $(MAKE) allmost
 
 gnu99build: clean
 	$(CC) -v
-	CFLAGS="-std=gnu99 -Werror" $(MAKE) allmost
+	CFLAGS="-std=gnu99 -Werror -O0" $(MAKE) allmost
 
 c11build: clean
 	$(CC) -v
-	CFLAGS="-std=c11 -Werror" $(MAKE) allmost
+	CFLAGS="-std=c11 -Werror -O0" $(MAKE) allmost
 
 bmix64build: clean
 	$(CC) -v
@@ -416,5 +435,5 @@ bmi32build: clean
 staticAnalyze: SCANBUILD ?= scan-build
 staticAnalyze:
 	$(CC) -v
-	CC=$(CC) CPPFLAGS=-g $(SCANBUILD) --status-bugs -v $(MAKE) allzstd examples contrib
+	CC=$(CC) CPPFLAGS=-g $(SCANBUILD) --status-bugs -v $(MAKE) zstd
 endif

Package.swift

@@ -0,0 +1,36 @@
+// swift-tools-version:5.0
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "zstd",
+    platforms: [
+        .macOS(.v10_10), .iOS(.v9), .tvOS(.v9)
+    ],
+    products: [
+        // Products define the executables and libraries a package produces, and make them visible to other packages.
+        .library(
+            name: "libzstd",
+            targets: [ "libzstd" ])
+    ],
+    dependencies: [
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+    ],
+    targets: [
+        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
+        // Targets can depend on other targets in this package, and on products in packages this package depends on.
+        .target(
+            name: "libzstd",
+            path: "lib",
+            sources: [ "common", "compress", "decompress", "dictBuilder" ],
+            publicHeadersPath: ".",
+            cSettings: [
+                .headerSearchPath(".")
+            ])
+    ],
+    swiftLanguageVersions: [.v5],
+    cLanguageStandard: .gnu11,
+    cxxLanguageStandard: .gnucxx14
+)

README.md

@@ -4,7 +4,8 @@ __Zstandard__, or `zstd` as short version, is a fast lossless compression algori
 targeting real-time compression scenarios at zlib-level and better compression ratios.
 It's backed by a very fast entropy stage, provided by [Huff0 and FSE library](https://github.com/Cyan4973/FiniteStateEntropy).
 
-The project is provided as an open-source dual [BSD](LICENSE) and [GPLv2](COPYING) licensed **C** library,
+Zstandard's format is stable and documented in [RFC8878](https://datatracker.ietf.org/doc/html/rfc8878). Multiple independent implementations are already available.
+This repository represents the reference implementation, provided as an open-source dual [BSD](LICENSE) and [GPLv2](COPYING) licensed **C** library,
 and a command line utility producing and decoding `.zst`, `.gz`, `.xz` and `.lz4` files.
 Should your project require another programming language,
 a list of known ports and bindings is provided on [Zstandard homepage](http://www.zstd.net/#other-languages).
@@ -17,8 +18,8 @@ a list of known ports and bindings is provided on [Zstandard homepage](http://ww
 [![Build status][CirrusDevBadge]][CirrusLink]
 [![Fuzzing Status][OSSFuzzBadge]][OSSFuzzLink]
 
-[travisDevBadge]: https://travis-ci.org/facebook/zstd.svg?branch=dev "Continuous Integration test suite"
-[travisLink]: https://travis-ci.org/facebook/zstd
+[travisDevBadge]: https://api.travis-ci.com/facebook/zstd.svg?branch=dev "Continuous Integration test suite"
+[travisLink]: https://travis-ci.com/facebook/zstd
 [AppveyorDevBadge]: https://ci.appveyor.com/api/projects/status/xt38wbdxjk5mrbem/branch/dev?svg=true "Windows test suite"
 [AppveyorLink]: https://ci.appveyor.com/project/YannCollet/zstd-p0yf0
 [CircleDevBadge]: https://circleci.com/gh/facebook/zstd/tree/dev.svg?style=shield "Short test suite"
@@ -31,8 +32,8 @@ a list of known ports and bindings is provided on [Zstandard homepage](http://ww
 ## Benchmarks
 
 For reference, several fast compression algorithms were tested and compared
-on a server running Arch Linux (`Linux version 5.5.11-arch1-1`),
-with a Core i9-9900K CPU @ 5.0GHz,
+on a desktop running Ubuntu 20.04 (`Linux 5.11.0-41-generic`),
+with a Core i7-9700K CPU @ 4.9GHz,
 using [lzbench], an open-source in-memory benchmark by @inikep
 compiled with [gcc] 9.3.0,
 on the [Silesia compression corpus].
@@ -43,25 +44,24 @@ on the [Silesia compression corpus].
 
 | Compressor name         | Ratio | Compression| Decompress.|
 | ---------------         | ------| -----------| ---------- |
-| **zstd 1.4.5 -1**       | 2.884 |   500 MB/s |  1660 MB/s |
-| zlib 1.2.11 -1          | 2.743 |    90 MB/s |   400 MB/s |
-| brotli 1.0.7 -0         | 2.703 |   400 MB/s |   450 MB/s |
-| **zstd 1.4.5 --fast=1** | 2.434 |   570 MB/s |  2200 MB/s |
-| **zstd 1.4.5 --fast=3** | 2.312 |   640 MB/s |  2300 MB/s |
-| quicklz 1.5.0 -1        | 2.238 |   560 MB/s |   710 MB/s |
-| **zstd 1.4.5 --fast=5** | 2.178 |   700 MB/s |  2420 MB/s |
-| lzo1x 2.10 -1           | 2.106 |   690 MB/s |   820 MB/s |
-| lz4 1.9.2               | 2.101 |   740 MB/s |  4530 MB/s |
-| **zstd 1.4.5 --fast=7** | 2.096 |   750 MB/s |  2480 MB/s |
-| lzf 3.6 -1              | 2.077 |   410 MB/s |   860 MB/s |
-| snappy 1.1.8            | 2.073 |   560 MB/s |  1790 MB/s |
+| **zstd 1.5.1 -1**       | 2.887 |   530 MB/s |  1700 MB/s |
+| [zlib] 1.2.11 -1        | 2.743 |    95 MB/s |   400 MB/s |
+| brotli 1.0.9 -0         | 2.702 |   395 MB/s |   450 MB/s |
+| **zstd 1.5.1 --fast=1** | 2.437 |   600 MB/s |  2150 MB/s |
+| **zstd 1.5.1 --fast=3** | 2.239 |   670 MB/s |  2250 MB/s |
+| quicklz 1.5.0 -1        | 2.238 |   540 MB/s |   760 MB/s |
+| **zstd 1.5.1 --fast=4** | 2.148 |   710 MB/s |  2300 MB/s |
+| lzo1x 2.10 -1           | 2.106 |   660 MB/s |   845 MB/s |
+| [lz4] 1.9.3             | 2.101 |   740 MB/s |  4500 MB/s |
+| lzf 3.6 -1              | 2.077 |   410 MB/s |   830 MB/s |
+| snappy 1.1.9            | 2.073 |   550 MB/s |  1750 MB/s |
 
 [zlib]: http://www.zlib.net/
-[LZ4]: http://www.lz4.org/
+[lz4]: http://www.lz4.org/
 
 The negative compression levels, specified with `--fast=#`,
-offer faster compression and decompression speed in exchange for some loss in
-compression ratio compared to level 1, as seen in the table above.
+offer faster compression and decompression speed
+at the cost of compression ratio (compared to level 1).
 
 Zstd can also offer stronger compression ratios at the cost of compression speed.
 Speed vs Compression trade-off is configurable by small increments.

appveyor.yml

@@ -23,34 +23,6 @@
       SCRIPT:   "make allzstd MOREFLAGS=-static"
       ARTIFACT: "true"
       BUILD:    "true"
-    - COMPILER: "clang"
-      HOST:     "mingw"
-      PLATFORM: "x64"
-      SCRIPT:   "MOREFLAGS='--target=x86_64-w64-mingw32 -Werror -Wconversion -Wno-sign-conversion' make -j allzstd V=1"
-      BUILD:    "true"
-
-    - COMPILER: "gcc"
-      HOST:     "mingw"
-      PLATFORM: "x64"
-      SCRIPT:   ""
-      TEST:     "cmake"
-
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Debug"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "Win32"
-      CONFIGURATION: "Debug"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Release"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "Win32"
-      CONFIGURATION: "Release"
 
     - COMPILER: "clang-cl"
       HOST:     "cmake-visual"
@@ -113,56 +85,6 @@
           appveyor PushArtifact zstd-win-release-%PLATFORM%.zip
       )
     )
-  - if [%HOST%]==[visual] (
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2008 %PLATFORM%\%CONFIGURATION% in %APPVEYOR_BUILD_FOLDER% &&
-      ECHO *** &&
-      msbuild "build\VS2008\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v90 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2008\bin\%PLATFORM%\%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2008/bin/%PLATFORM%/%CONFIGURATION%/*.exe &&
-      COPY build\VS2008\bin\%PLATFORM%\%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2008_%PLATFORM%_%CONFIGURATION%.exe &&
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2010 %PLATFORM%\%CONFIGURATION% &&
-      ECHO *** &&
-      msbuild "build\VS2010\zstd.sln" %ADDITIONALPARAM% /m /verbosity:minimal /property:PlatformToolset=v100 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      msbuild "build\VS2010\zstd.sln" %ADDITIONALPARAM% /m /verbosity:minimal /property:PlatformToolset=v100 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2010_%PLATFORM%_%CONFIGURATION%.exe &&
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2012 %PLATFORM%\%CONFIGURATION% &&
-      ECHO *** &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v110 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v110 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2012_%PLATFORM%_%CONFIGURATION%.exe &&
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2013 %PLATFORM%\%CONFIGURATION% &&
-      ECHO *** &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v120 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v120 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2013_%PLATFORM%_%CONFIGURATION%.exe &&
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2015 %PLATFORM%\%CONFIGURATION% &&
-      ECHO *** &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v140 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v140 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2015_%PLATFORM%_%CONFIGURATION%.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe tests\
-    )
   - if [%HOST%]==[cmake-visual] (
       ECHO *** &&
       ECHO *** Building %CMAKE_GENERATOR% ^(%CMAKE_GENERATOR_TOOLSET%^) %PLATFORM%\%CONFIGURATION% &&
@@ -186,18 +108,6 @@
       cd ..\..\.. &&
       make clean
     )
-  - SET "FUZZERTEST=-T30s"
-  - if [%HOST%]==[visual] if [%CONFIGURATION%]==[Release] (
-      CD tests &&
-      SET ZSTD_BIN=./zstd.exe&&
-      SET DATAGEN_BIN=./datagen.exe&&
-      sh -e playTests.sh --test-large-data &&
-      fullbench.exe -i1 &&
-      fullbench.exe -i1 -P0 &&
-      fuzzer_VS2012_%PLATFORM%_Release.exe %FUZZERTEST% &&
-      fuzzer_VS2013_%PLATFORM%_Release.exe %FUZZERTEST% &&
-      fuzzer_VS2015_%PLATFORM%_Release.exe %FUZZERTEST%
-    )
 
 
 # The following tests are for regular pushes
@@ -208,38 +118,26 @@
   version: 1.0.{build}
   environment:
     matrix:
+    - COMPILER: "visual"
+      HOST:     "visual"
+      PLATFORM: "x64"
+      CONFIGURATION: "Debug"
+    - COMPILER: "visual"
+      HOST:     "visual"
+      PLATFORM: "Win32"
+      CONFIGURATION: "Debug"
+    - COMPILER: "visual"
+      HOST:     "visual"
+      PLATFORM: "x64"
+      CONFIGURATION: "Release"
+    - COMPILER: "visual"
+      HOST:     "visual"
+      PLATFORM: "Win32"
+      CONFIGURATION: "Release"
+
     - COMPILER: "gcc"
       HOST:     "cygwin"
       PLATFORM: "x64"
-    - COMPILER: "gcc"
-      HOST:     "mingw"
-      PLATFORM: "x64"
-      SCRIPT:   "CFLAGS=-Werror make -j allzstd DEBUGLEVEL=2"
-    - COMPILER: "gcc"
-      HOST:     "mingw"
-      PLATFORM: "x86"
-      SCRIPT:   "CFLAGS=-Werror make -j allzstd"
-    - COMPILER: "clang"
-      HOST:     "mingw"
-      PLATFORM: "x64"
-      SCRIPT:   "CFLAGS='--target=x86_64-w64-mingw32 -Werror -Wconversion -Wno-sign-conversion' make -j allzstd V=1"
-
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Debug"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "Win32"
-      CONFIGURATION: "Debug"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Release"
-    - COMPILER: "visual"
-      HOST:     "visual"
-      PLATFORM: "Win32"
-      CONFIGURATION: "Release"
 
     - COMPILER: "clang-cl"
       HOST:     "cmake-visual"
@@ -260,12 +158,6 @@
         cmake,^
         make
     )
-  - if [%HOST%]==[mingw] (
-      SET "PATH_MINGW32=C:\mingw-w64\i686-6.3.0-posix-dwarf-rt_v5-rev1\mingw32\bin" &&
-      SET "PATH_MINGW64=C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin" &&
-      COPY C:\msys64\usr\bin\make.exe C:\mingw-w64\i686-6.3.0-posix-dwarf-rt_v5-rev1\mingw32\bin\make.exe &&
-      COPY C:\msys64\usr\bin\make.exe C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin\make.exe
-    )
   - IF [%HOST%]==[visual] IF [%PLATFORM%]==[x64] (
       SET ADDITIONALPARAM=/p:LibraryPath="C:\Program Files\Microsoft SDKs\Windows\v7.1\lib\x64;c:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\lib\amd64;C:\Program Files (x86)\Microsoft Visual Studio 10.0\;C:\Program Files (x86)\Microsoft Visual Studio 10.0\lib\amd64;"
     )
@@ -283,30 +175,6 @@
         ctest -V -L Medium;
       "
     )
-  - if [%HOST%]==[mingw] (
-      ( if [%PLATFORM%]==[x64] (
-        SET "PATH=%PATH_MINGW64%;%PATH_ORIGINAL%"
-      ) else if [%PLATFORM%]==[x86] (
-        SET "PATH=%PATH_MINGW32%;%PATH_ORIGINAL%"
-      ) ) &&
-      make -v &&
-      sh -c "%COMPILER% -v" &&
-      set "CC=%COMPILER%" &&
-      sh -c "%SCRIPT%"
-    )
-  - if [%HOST%]==[visual] (
-      ECHO *** &&
-      ECHO *** Building Visual Studio 2015 %PLATFORM%\%CONFIGURATION% &&
-      ECHO *** &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v140 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v140 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
-      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
-      MD5sum build/VS2010/bin/%PLATFORM%_%CONFIGURATION%/*.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\fuzzer.exe tests\fuzzer_VS2015_%PLATFORM%_%CONFIGURATION%.exe &&
-      COPY build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe tests\
-    )
   - if [%HOST%]==[cmake-visual] (
       ECHO *** &&
       ECHO *** Building %CMAKE_GENERATOR% ^(%CMAKE_GENERATOR_TOOLSET%^) %PLATFORM%\%CONFIGURATION% &&
@@ -316,12 +184,22 @@
       POPD &&
       ECHO ***
     )
+  - if [%HOST%]==[visual] (
+      ECHO *** &&
+      ECHO *** Building Visual Studio 2012 %PLATFORM%\%CONFIGURATION% &&
+      ECHO *** &&
+      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v110 /p:ForceImportBeforeCppTargets=%APPVEYOR_BUILD_FOLDER%\build\VS2010\CompileAsCpp.props /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
+      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe &&
+      msbuild "build\VS2010\zstd.sln" /m /verbosity:minimal /property:PlatformToolset=v110 /t:Clean,Build /p:Platform=%PLATFORM% /p:Configuration=%CONFIGURATION% /logger:"C:\Program Files\AppVeyor\BuildAgent\Appveyor.MSBuildLogger.dll" &&
+      DIR build\VS2010\bin\%PLATFORM%_%CONFIGURATION%\*.exe
+    )
 
 
   test_script:
   - ECHO Testing %COMPILER% %PLATFORM% %CONFIGURATION%
+  - SET "FUZZERTEST=-T10s"
   - if [%HOST%]==[mingw] (
       set "CC=%COMPILER%" &&
       make clean &&
       make check
-    )
+    )

build/VS2008/fullbench/fullbench.vcproj

@@ -45,7 +45,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs;$(SolutionDir)..\..\programs\legacy"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -121,7 +121,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs;$(SolutionDir)..\..\programs\legacy"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
@@ -195,7 +195,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs;$(SolutionDir)..\..\programs\legacy"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -272,7 +272,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs;$(SolutionDir)..\..\programs\legacy"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"

build/VS2008/fuzzer/fuzzer.vcproj

@@ -45,7 +45,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\compress;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -121,7 +121,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\compress;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"
@@ -195,7 +195,7 @@
 				Name="VCCLCompilerTool"
 				Optimization="0"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\compress;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\programs"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE"
 				MinimalRebuild="true"
 				BasicRuntimeChecks="3"
 				RuntimeLibrary="3"
@@ -272,7 +272,7 @@
 				EnableIntrinsicFunctions="true"
 				OmitFramePointers="true"
 				AdditionalIncludeDirectories="$(SolutionDir)..\..\lib;$(SolutionDir)..\..\lib\common;$(SolutionDir)..\..\lib\dictBuilder;$(SolutionDir)..\..\lib\legacy;$(SolutionDir)..\..\lib\compress;$(SolutionDir)..\..\programs"
-				PreprocessorDefinitions="ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE"
 				RuntimeLibrary="0"
 				EnableFunctionLevelLinking="true"
 				UsePrecompiledHeader="0"

build/VS2008/zstd/zstd.vcproj

@@ -384,6 +384,10 @@
 				RelativePath="..\..\..\programs\fileio.c"
 				>
 			</File>
+			<File
+                RelativePath="..\..\..\programs\fileio_asyncio.c"
+                >
+            </File>
 			<File
 				RelativePath="..\..\..\lib\compress\fse_compress.c"
 				>

build/VS2010/fullbench-dll/fullbench-dll.vcxproj

@@ -90,7 +90,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -108,7 +108,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -127,7 +127,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <EnablePREfast>false</EnablePREfast>
       <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
@@ -150,7 +150,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;ZSTD_DLL_IMPORT=1;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>false</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>

build/VS2010/fullbench/fullbench.vcxproj

@@ -90,7 +90,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -105,7 +105,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -122,7 +122,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <EnablePREfast>false</EnablePREfast>
       <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
@@ -142,7 +142,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>false</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>

build/VS2010/fuzzer/fuzzer.vcxproj

@@ -90,7 +90,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -105,7 +105,7 @@
       </PrecompiledHeader>
       <WarningLevel>Level4</WarningLevel>
       <Optimization>Disabled</Optimization>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>ZSTD_MULTITHREAD=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>true</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
     </ClCompile>
@@ -122,7 +122,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <EnablePREfast>false</EnablePREfast>
       <TreatWarningAsError>false</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
@@ -142,7 +142,7 @@
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
-      <PreprocessorDefinitions>ZSTD_DISABLE_DEPRECATE_WARNINGS=1;ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>ZSTD_MULTITHREAD=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <TreatWarningAsError>false</TreatWarningAsError>
       <EnablePREfast>false</EnablePREfast>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>

build/VS2010/zstd/zstd.vcxproj

@@ -62,6 +62,7 @@
     <ClCompile Include="..\..\..\programs\datagen.c" />
     <ClCompile Include="..\..\..\programs\dibio.c" />
     <ClCompile Include="..\..\..\programs\fileio.c" />
+    <ClCompile Include="..\..\..\programs\fileio_asyncio.c" />
     <ClCompile Include="..\..\..\programs\zstdcli.c" />
     <ClCompile Include="..\..\..\programs\zstdcli_trace.c" />
   </ItemGroup>

build/VS_scripts/build.generic.cmd

@@ -19,10 +19,10 @@ GOTO build
 :display_help
 
 echo Syntax: build.generic.cmd msbuild_version msbuild_platform msbuild_configuration msbuild_toolset
-echo   msbuild_version:          VS installed version (VS2012, VS2013, VS2015, VS2017, ...)
+echo   msbuild_version:          VS installed version (VS2012, VS2013, VS2015, VS2017, VS2019, ...)
 echo   msbuild_platform:         Platform (x64 or Win32)
 echo   msbuild_configuration:    VS configuration (Release or Debug)
-echo   msbuild_toolset:          Platform Toolset (v100, v110, v120, v140, v141)
+echo   msbuild_toolset:          Platform Toolset (v100, v110, v120, v140, v141, v142, ...)
 
 EXIT /B 1
 
@@ -43,6 +43,16 @@ IF %msbuild_version% == VS2017 (
 	IF EXIST %msbuild_vs2017enterprise% SET msbuild=%msbuild_vs2017enterprise%
 )
 
+:: VS2019
+SET msbuild_vs2019community="%programfiles(x86)%\Microsoft Visual Studio\2019\Community\MSBuild\Current\Bin\MSBuild.exe"
+SET msbuild_vs2019professional="%programfiles(x86)%\Microsoft Visual Studio\2019\Professional\MSBuild\Current\Bin\MSBuild.exe"
+SET msbuild_vs2019enterprise="%programfiles(x86)%\Microsoft Visual Studio\2019\Enterprise\MSBuild\Current\Bin\MSBuild.exe"
+IF %msbuild_version% == VS2019 (
+	IF EXIST %msbuild_vs2019community% SET msbuild=%msbuild_vs2019community%
+	IF EXIST %msbuild_vs2019professional% SET msbuild=%msbuild_vs2019professional%
+	IF EXIST %msbuild_vs2019enterprise% SET msbuild=%msbuild_vs2019enterprise%
+)
+
 SET project="%~p0\..\VS2010\zstd.sln"
 
 SET msbuild_params=/verbosity:minimal /nologo /t:Clean,Build /p:Platform=%msbuild_platform% /p:Configuration=%msbuild_configuration%

build/cmake/CMakeLists.txt

@@ -92,8 +92,14 @@ else ()
     add_definitions(-DZSTD_LEGACY_SUPPORT=0)
 endif ()
 
+if (ANDROID)
+    set(ZSTD_MULTITHREAD_SUPPORT_DEFAULT OFF)
+else()
+    set(ZSTD_MULTITHREAD_SUPPORT_DEFAULT ON)
+endif()
+
 # Multi-threading support
-option(ZSTD_MULTITHREAD_SUPPORT "MULTITHREADING SUPPORT" ON)
+option(ZSTD_MULTITHREAD_SUPPORT "MULTITHREADING SUPPORT" ${ZSTD_MULTITHREAD_SUPPORT_DEFAULT})
 
 if (ZSTD_MULTITHREAD_SUPPORT)
     message(STATUS "ZSTD_MULTITHREAD_SUPPORT is enabled")

build/cmake/contrib/pzstd/CMakeLists.txt

@@ -21,10 +21,16 @@ add_executable(pzstd ${PROGRAMS_DIR}/util.c ${PZSTD_DIR}/main.cpp ${PZSTD_DIR}/O
 set_property(TARGET pzstd APPEND PROPERTY COMPILE_DEFINITIONS "NDEBUG")
 set_property(TARGET pzstd APPEND PROPERTY COMPILE_OPTIONS "-Wno-shadow")
 
+if (ZSTD_BUILD_SHARED)
+    set(ZSTD_LIB libzstd_shared)
+else()
+    set(ZSTD_LIB libzstd_static)
+endif()
+
 set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
 if (CMAKE_USE_PTHREADS_INIT)
-    target_link_libraries(pzstd libzstd_shared ${CMAKE_THREAD_LIBS_INIT})
+  target_link_libraries(pzstd ${ZSTD_LIB} ${CMAKE_THREAD_LIBS_INIT})
 else()
     message(SEND_ERROR "ZSTD currently does not support thread libraries other than pthreads")
 endif()

build/cmake/lib/CMakeLists.txt

@@ -7,7 +7,7 @@
 # in the COPYING file in the root directory of this source tree).
 # ################################################################
 
-project(libzstd C)
+project(libzstd C ASM)
 
 set(CMAKE_INCLUDE_CURRENT_DIR TRUE)
 option(ZSTD_BUILD_STATIC "BUILD STATIC LIBRARIES" ON)
@@ -22,7 +22,12 @@ include_directories(${LIBRARY_DIR} ${LIBRARY_DIR}/common)
 
 file(GLOB CommonSources ${LIBRARY_DIR}/common/*.c)
 file(GLOB CompressSources ${LIBRARY_DIR}/compress/*.c)
-file(GLOB DecompressSources ${LIBRARY_DIR}/decompress/*.c)
+if (MSVC)
+    file(GLOB DecompressSources ${LIBRARY_DIR}/decompress/*.c)
+    add_compile_options(-DZSTD_DISABLE_ASM)
+else ()
+    file(GLOB DecompressSources ${LIBRARY_DIR}/decompress/*.c ${LIBRARY_DIR}/decompress/*.S)
+endif ()
 file(GLOB DictBuilderSources ${LIBRARY_DIR}/dictBuilder/*.c)
 
 set(Sources
@@ -106,7 +111,7 @@ if (MSVC)
 endif ()
 
 # With MSVC static library needs to be renamed to avoid conflict with import library
-if (MSVC)
+if (MSVC OR (WIN32 AND CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND NOT MINGW))
     set(STATIC_LIBRARY_BASE_NAME zstd_static)
 else ()
     set(STATIC_LIBRARY_BASE_NAME zstd)
@@ -168,6 +173,7 @@ install(TARGETS ${library_targets}
     ARCHIVE DESTINATION "${CMAKE_INSTALL_LIBDIR}"
     LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
     RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
+    BUNDLE DESTINATION "${CMAKE_INSTALL_BINDIR}"
     )
 
 # uninstall target

build/cmake/programs/CMakeLists.txt

@@ -32,12 +32,14 @@ if (MSVC)
     set(PlatformDependResources ${MSVC_RESOURCE_DIR}/zstd.rc)
 endif ()
 
-add_executable(zstd ${PROGRAMS_DIR}/zstdcli.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${PROGRAMS_DIR}/fileio.c ${PROGRAMS_DIR}/benchfn.c ${PROGRAMS_DIR}/benchzstd.c ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/dibio.c ${PROGRAMS_DIR}/zstdcli_trace.c ${PlatformDependResources})
+add_executable(zstd ${PROGRAMS_DIR}/zstdcli.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${PROGRAMS_DIR}/fileio.c ${PROGRAMS_DIR}/fileio_asyncio.c ${PROGRAMS_DIR}/benchfn.c ${PROGRAMS_DIR}/benchzstd.c ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/dibio.c ${PROGRAMS_DIR}/zstdcli_trace.c ${PlatformDependResources})
 target_link_libraries(zstd ${PROGRAMS_ZSTD_LINK_TARGET})
 if (CMAKE_SYSTEM_NAME MATCHES "(Solaris|SunOS)")
     target_link_libraries(zstd rt)
 endif ()
-install(TARGETS zstd RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
+install(TARGETS zstd
+  RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
+  BUNDLE DESTINATION "${CMAKE_INSTALL_BINDIR}")
 
 if (UNIX)
     add_custom_target(zstdcat ALL ${CMAKE_COMMAND} -E create_symlink zstd zstdcat DEPENDS zstd COMMENT "Creating zstdcat symlink")
@@ -73,7 +75,7 @@ if (UNIX)
         ${CMAKE_CURRENT_BINARY_DIR}/zstdless.1
         DESTINATION "${MAN_INSTALL_DIR}")
 
-    add_executable(zstd-frugal ${PROGRAMS_DIR}/zstdcli.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${PROGRAMS_DIR}/fileio.c)
+    add_executable(zstd-frugal ${PROGRAMS_DIR}/zstdcli.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${PROGRAMS_DIR}/fileio.c ${PROGRAMS_DIR}/fileio_asyncio.c)
     target_link_libraries(zstd-frugal ${PROGRAMS_ZSTD_LINK_TARGET})
     set_property(TARGET zstd-frugal APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_NOBENCH;ZSTD_NODICT;ZSTD_NOTRACE")
 endif ()

build/cmake/tests/CMakeLists.txt

@@ -57,7 +57,7 @@ target_link_libraries(datagen libzstd_static)
 # fullbench
 #
 add_executable(fullbench ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${PROGRAMS_DIR}/benchfn.c ${PROGRAMS_DIR}/benchzstd.c ${TESTS_DIR}/fullbench.c)
-set_property(TARGET fullbench APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_DISABLE_DEPRECATE_WARNINGS")
+set_property(TARGET fullbench APPEND PROPERTY COMPILE_OPTIONS "-Wno-deprecated-declarations")
 target_link_libraries(fullbench libzstd_static)
 add_test(NAME fullbench COMMAND fullbench ${ZSTD_FULLBENCH_FLAGS})
 
@@ -65,7 +65,7 @@ add_test(NAME fullbench COMMAND fullbench ${ZSTD_FULLBENCH_FLAGS})
 # fuzzer
 #
 add_executable(fuzzer ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${TESTS_DIR}/fuzzer.c)
-set_property(TARGET fuzzer APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_DISABLE_DEPRECATE_WARNINGS")
+set_property(TARGET fuzzer APPEND PROPERTY COMPILE_OPTIONS "-Wno-deprecated-declarations")
 target_link_libraries(fuzzer libzstd_static)
 AddTestFlagsOption(ZSTD_FUZZER_FLAGS "$ENV{FUZZERTEST} $ENV{FUZZER_FLAGS}"
     "Semicolon-separated list of flags to pass to the fuzzer test (see `fuzzer -h` for usage)")
@@ -78,7 +78,7 @@ add_test(NAME fuzzer COMMAND fuzzer ${ZSTD_FUZZER_FLAGS})
 # zstreamtest
 #
 add_executable(zstreamtest ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${TESTS_DIR}/seqgen.c ${TESTS_DIR}/zstreamtest.c)
-set_property(TARGET zstreamtest APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_DISABLE_DEPRECATE_WARNINGS")
+set_property(TARGET zstreamtest APPEND PROPERTY COMPILE_OPTIONS "-Wno-deprecated-declarations")
 target_link_libraries(zstreamtest libzstd_static)
 AddTestFlagsOption(ZSTD_ZSTREAM_FLAGS "$ENV{ZSTREAM_TESTTIME} $ENV{FUZZER_FLAGS}"
     "Semicolon-separated list of flags to pass to the zstreamtest test (see `zstreamtest -h` for usage)")

build/meson/contrib/pzstd/meson.build

@@ -18,7 +18,7 @@ pzstd_sources = [join_paths(zstd_rootdir, 'programs/util.c'),
   join_paths(zstd_rootdir, 'contrib/pzstd/SkippableFrame.cpp')]
 pzstd = executable('pzstd',
   pzstd_sources,
-  cpp_args: [ '-DNDEBUG', '-Wno-shadow', '-pedantic' ],
+  cpp_args: [ '-DNDEBUG', '-Wno-shadow', '-Wno-deprecated-declarations' ],
   include_directories: pzstd_includes,
   dependencies: [ libzstd_dep, thread_dep ],
   install: true)

build/meson/lib/meson.build

@@ -45,6 +45,15 @@ libzstd_sources = [join_paths(zstd_rootdir, 'lib/common/entropy_common.c'),
   join_paths(zstd_rootdir, 'lib/dictBuilder/divsufsort.c'),
   join_paths(zstd_rootdir, 'lib/dictBuilder/zdict.c')]
 
+# really we need anything that defines __GNUC__ as that is what ZSTD_ASM_SUPPORTED is gated on
+# but these are the two compilers that are supported in tree and actually handle this correctly
+# Otherwise, explicitly disable assmebly.
+if [compiler_gcc, compiler_clang].contains(cc_id)
+  libzstd_sources += join_paths(zstd_rootdir, 'lib/decompress/huf_decompress_amd64.S')
+else
+  add_project_arguments('-DZSTD_DISABLE_ASM', language: 'c')
+endif
+
 # Explicit define legacy support
 add_project_arguments('-DZSTD_LEGACY_SUPPORT=@0@'.format(legacy_level),
   language: 'c')
@@ -108,6 +117,7 @@ libzstd = library('zstd',
   libzstd_sources,
   include_directories: libzstd_includes,
   c_args: libzstd_c_args,
+  gnu_symbol_visibility: 'hidden',
   dependencies: libzstd_deps,
   install: true,
   version: zstd_libversion)

build/meson/meson.build

@@ -14,10 +14,14 @@ project('zstd',
   default_options : [
     'c_std=gnu99',
     'cpp_std=c++11',
-    'buildtype=release'
+    'buildtype=release',
+    'warning_level=3',
+    # -Wdocumentation does not actually pass, nor do the test binaries,
+    # so this isn't safe
+    #'werror=true'
   ],
   version: 'DUMMY',
-  meson_version: '>=0.47.0')
+  meson_version: '>=0.48.0')
 
 cc = meson.get_compiler('c')
 cxx = meson.get_compiler('cpp')
@@ -106,10 +110,8 @@ use_lz4 = lz4_dep.found()
 add_project_arguments('-DXXH_NAMESPACE=ZSTD_', language: ['c'])
 
 if [compiler_gcc, compiler_clang].contains(cc_id)
-  common_warning_flags = [ '-Wextra', '-Wundef', '-Wshadow', '-Wcast-align', '-Wcast-qual' ]
+  common_warning_flags = [ '-Wundef', '-Wshadow', '-Wcast-align', '-Wcast-qual' ]
   if cc_id == compiler_clang
-    # Should use Meson's own --werror build option
-    #common_warning_flags += '-Werror'
     common_warning_flags += ['-Wconversion', '-Wno-sign-conversion', '-Wdocumentation']
   endif
   cc_compile_flags = cc.get_supported_arguments(common_warning_flags + ['-Wstrict-prototypes'])

build/meson/meson_options.txt

@@ -10,7 +10,7 @@
 
 # Read guidelines from https://wiki.gnome.org/Initiatives/GnomeGoals/MesonPorting
 
-option('legacy_level', type: 'integer', min: 0, max: 7, value: '5',
+option('legacy_level', type: 'integer', min: 0, max: 7, value: 5,
   description: 'Support any legacy format: 7 to 1 for v0.7+ to v0.1+')
 option('debug_level', type: 'integer', min: 0, max: 9, value: 1,
   description: 'Enable run-time debug. See lib/common/debug.h')

build/meson/programs/meson.build

@@ -14,18 +14,31 @@ zstd_programs_sources = [join_paths(zstd_rootdir, 'programs/zstdcli.c'),
   join_paths(zstd_rootdir, 'programs/util.c'),
   join_paths(zstd_rootdir, 'programs/timefn.c'),
   join_paths(zstd_rootdir, 'programs/fileio.c'),
+  join_paths(zstd_rootdir, 'programs/fileio_asyncio.c'),
   join_paths(zstd_rootdir, 'programs/benchfn.c'),
   join_paths(zstd_rootdir, 'programs/benchzstd.c'),
   join_paths(zstd_rootdir, 'programs/datagen.c'),
   join_paths(zstd_rootdir, 'programs/dibio.c'),
-  join_paths(zstd_rootdir, 'programs/zstdcli_trace.c')]
-
-zstd_c_args = libzstd_debug_cflags
-if use_multi_thread
-  zstd_c_args += [ '-DZSTD_MULTITHREAD' ]
-endif
+  join_paths(zstd_rootdir, 'programs/zstdcli_trace.c'),
+  # needed due to use of private symbol + -fvisibility=hidden
+  join_paths(zstd_rootdir, 'lib/common/xxhash.c'),
+  join_paths(zstd_rootdir, 'lib/common/pool.c'),
+  join_paths(zstd_rootdir, 'lib/common/zstd_common.c'),
+  join_paths(zstd_rootdir, 'lib/common/error_private.c')]
 
 zstd_deps = [ libzstd_dep ]
+zstd_c_args = libzstd_debug_cflags
+
+zstd_frugal_deps = [ libzstd_dep ]
+zstd_frugal_c_args = [ '-DZSTD_NOBENCH', '-DZSTD_NODICT', '-DZSTD_NOTRACE' ]
+
+if use_multi_thread
+  zstd_deps += [ thread_dep ]
+  zstd_c_args += [ '-DZSTD_MULTITHREAD' ]
+  zstd_frugal_deps += [ thread_dep ]
+  zstd_frugal_c_args += [ '-DZSTD_MULTITHREAD' ]
+endif
+
 if use_zlib
   zstd_deps += [ zlib_dep ]
   zstd_c_args += [ '-DZSTD_GZCOMPRESS', '-DZSTD_GZDECOMPRESS' ]
@@ -67,14 +80,18 @@ zstd = executable('zstd',
 zstd_frugal_sources = [join_paths(zstd_rootdir, 'programs/zstdcli.c'),
   join_paths(zstd_rootdir, 'programs/timefn.c'),
   join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/fileio.c')]
+  join_paths(zstd_rootdir, 'programs/fileio.c'),
+  join_paths(zstd_rootdir, 'programs/fileio_asyncio.c'),
+  join_paths(zstd_rootdir, 'lib/common/pool.c'),
+  join_paths(zstd_rootdir, 'lib/common/zstd_common.c'),
+  join_paths(zstd_rootdir, 'lib/common/error_private.c')]
 
 # Minimal target, with only zstd compression and decompression.
 # No bench. No legacy.
 executable('zstd-frugal',
   zstd_frugal_sources,
-  dependencies: libzstd_dep,
-  c_args: [ '-DZSTD_NOBENCH', '-DZSTD_NODICT', '-DZSTD_NOTRACE' ],
+  dependencies: zstd_frugal_deps,
+  c_args: zstd_frugal_c_args,
   install: true)
 
 install_data(join_paths(zstd_rootdir, 'programs/zstdgrep'),

build/meson/tests/meson.build

@@ -29,64 +29,62 @@ ZSTDRTTEST = ['--test-large-data']
 
 test_includes = [ include_directories(join_paths(zstd_rootdir, 'programs')) ]
 
-datagen_sources = [join_paths(zstd_rootdir, 'programs/datagen.c'),
-  join_paths(zstd_rootdir, 'tests/datagencli.c')]
+testcommon_sources = [join_paths(zstd_rootdir, 'programs/datagen.c'),
+  join_paths(zstd_rootdir, 'programs/util.c'),
+  join_paths(zstd_rootdir, 'programs/timefn.c'),
+  join_paths(zstd_rootdir, 'programs/benchfn.c'),
+  join_paths(zstd_rootdir, 'programs/benchzstd.c')]
+
+testcommon = static_library('testcommon',
+  testcommon_sources,
+  # needed due to use of private symbol + -fvisibility=hidden
+  objects: libzstd.extract_all_objects(recursive: false))
+
+testcommon_dep = declare_dependency(link_with: testcommon,
+  dependencies: libzstd_deps,
+  include_directories: libzstd_includes)
+
+datagen_sources = [join_paths(zstd_rootdir, 'tests/datagencli.c')]
 datagen = executable('datagen',
   datagen_sources,
   c_args: [ '-DNDEBUG' ],
   include_directories: test_includes,
-  dependencies: libzstd_dep,
+  dependencies: testcommon_dep,
   install: false)
 
-fullbench_sources = [join_paths(zstd_rootdir, 'programs/datagen.c'),
-  join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'programs/benchfn.c'),
-  join_paths(zstd_rootdir, 'programs/benchzstd.c'),
-  join_paths(zstd_rootdir, 'tests/fullbench.c')]
+fullbench_sources = [join_paths(zstd_rootdir, 'tests/fullbench.c')]
 fullbench = executable('fullbench',
   fullbench_sources,
   include_directories: test_includes,
-  dependencies: libzstd_dep,
+  dependencies: testcommon_dep,
   install: false)
 
-fuzzer_sources = [join_paths(zstd_rootdir, 'programs/datagen.c'),
-  join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'tests/fuzzer.c')]
+fuzzer_sources = [join_paths(zstd_rootdir, 'tests/fuzzer.c')]
 fuzzer = executable('fuzzer',
   fuzzer_sources,
   include_directories: test_includes,
-  dependencies: libzstd_dep,
+  dependencies: [ testcommon_dep, thread_dep ],
   install: false)
 
-zstreamtest_sources = [join_paths(zstd_rootdir, 'programs/datagen.c'),
-  join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'tests/seqgen.c'),
+zstreamtest_sources = [join_paths(zstd_rootdir, 'tests/seqgen.c'),
   join_paths(zstd_rootdir, 'tests/zstreamtest.c')]
 zstreamtest = executable('zstreamtest',
   zstreamtest_sources,
   include_directories: test_includes,
-  dependencies: libzstd_dep,
+  dependencies: testcommon_dep,
   install: false)
 
-paramgrill_sources = [join_paths(zstd_rootdir, 'programs/benchfn.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'programs/benchzstd.c'),
-  join_paths(zstd_rootdir, 'programs/datagen.c'),
-  join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'tests/paramgrill.c')]
+paramgrill_sources = [join_paths(zstd_rootdir, 'tests/paramgrill.c')]
 paramgrill = executable('paramgrill',
   paramgrill_sources,
   include_directories: test_includes,
-  dependencies: [ libzstd_dep, libm_dep ],
+  dependencies: [ testcommon_dep, libm_dep ],
   install: false)
 
 roundTripCrash_sources = [join_paths(zstd_rootdir, 'tests/roundTripCrash.c')]
 roundTripCrash = executable('roundTripCrash',
   roundTripCrash_sources,
-  dependencies: [ libzstd_dep ],
+  dependencies: [ testcommon_dep ],
   install: false)
 
 longmatch_sources = [join_paths(zstd_rootdir, 'tests/longmatch.c')]
@@ -111,18 +109,14 @@ if 0 < legacy_level and legacy_level <= 4
     install: false)
 endif
 
-decodecorpus_sources = [join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'tests/decodecorpus.c')]
+decodecorpus_sources = [join_paths(zstd_rootdir, 'tests/decodecorpus.c')]
 decodecorpus = executable('decodecorpus',
   decodecorpus_sources,
   include_directories: test_includes,
-  dependencies: [ libzstd_dep, libm_dep ],
+  dependencies: [ testcommon_dep, libm_dep ],
   install: false)
 
-poolTests_sources = [join_paths(zstd_rootdir, 'programs/util.c'),
-  join_paths(zstd_rootdir, 'programs/timefn.c'),
-  join_paths(zstd_rootdir, 'tests/poolTests.c'),
+poolTests_sources = [join_paths(zstd_rootdir, 'tests/poolTests.c'),
   join_paths(zstd_rootdir, 'lib/common/pool.c'),
   join_paths(zstd_rootdir, 'lib/common/threading.c'),
   join_paths(zstd_rootdir, 'lib/common/zstd_common.c'),
@@ -130,7 +124,7 @@ poolTests_sources = [join_paths(zstd_rootdir, 'programs/util.c'),
 poolTests = executable('poolTests',
   poolTests_sources,
   include_directories: test_includes,
-  dependencies: [ libzstd_dep, thread_dep ],
+  dependencies: [ testcommon_dep, thread_dep ],
   install: false)
 
 checkTag_sources = [join_paths(zstd_rootdir, 'tests/checkTag.c')]
@@ -186,10 +180,6 @@ test('test-zstream-1',
   zstreamtest,
   args: ['-v', ZSTREAM_TESTTIME] + FUZZER_FLAGS,
   timeout: 240)
-test('test-zstream-2',
-  zstreamtest,
-  args: ['-mt', '-t1', ZSTREAM_TESTTIME] + FUZZER_FLAGS,
-  timeout: 120)
 test('test-zstream-3',
   zstreamtest,
   args: ['--newapi', '-t1', ZSTREAM_TESTTIME] + FUZZER_FLAGS,

build/single_file_libs/README.md

@@ -12,7 +12,7 @@ This is the most common use case. The decompression library is small, adding, fo
 Create `zstddeclib.c` from the Zstd source using:
 ```
 cd zstd/build/single_file_libs
-./combine.sh -r ../../lib -o zstddeclib.c zstddeclib-in.c
+python3 combine.py -r ../../lib -x legacy/zstd_legacy.h -o zstddeclib.c zstddeclib-in.c
 ```
 Then add the resulting file to your project (see the [example files](examples)).
 
@@ -26,7 +26,7 @@ The same tool can amalgamate the entire Zstd library for ease of adding both com
 Create `zstd.c` from the Zstd source using:
 ```
 cd zstd/build/single_file_libs
-./combine.sh -r ../../lib -o zstd.c zstd-in.c
+python3 combine.py -r ../../lib -x legacy/zstd_legacy.h -k zstd.h -o zstd.c zstd-in.c
 ```
 It's possible to create a compressor-only library but since the decompressor is so small in comparison this doesn't bring much of a gain (but for the curious, simply remove the files in the _decompress_ section at the end of `zstd-in.c`).
 

build/single_file_libs/build_library_test.sh

@@ -69,7 +69,7 @@ fi
 echo "Single file library creation script: PASSED"
 
 # Copy the header to here (for the tests)
-cp "$ZSTD_SRC_ROOT/zstd.h" zstd.h
+cp "$ZSTD_SRC_ROOT/zstd.h" examples/zstd.h
 
 # Compile the generated output
 cc -Wall -Wextra -Werror -Wshadow -pthread -I. -Os -g0 -o $OUT_FILE zstd.c examples/roundtrip.c

build/single_file_libs/combine.py

@@ -0,0 +1,234 @@
+#!/usr/bin/env python3
+
+# Tool to bundle multiple C/C++ source files, inlining any includes.
+# 
+# Note: there are two types of exclusion options: the '-x' flag, which besides
+# excluding a file also adds an #error directive in place of the #include, and
+# the '-k' flag, which keeps the #include and doesn't inline the file. The
+# intended use cases are: '-x' for files that would normally be #if'd out, so
+# features that 100% won't be used in the amalgamated file, for which every
+# occurrence adds the error, and '-k' for headers that we wish to manually
+# include, such as a project's public API, for which occurrences after the first
+# are removed.
+# 
+# Todo: the error handling could be better, which currently throws and halts
+# (which is functional just not very friendly).
+# 
+# Author: Carl Woffenden, Numfum GmbH (this script is released under a CC0 license/Public Domain)
+
+import argparse, re, sys
+
+from pathlib import Path
+from typing import Any, List, Optional, Pattern, Set, TextIO
+
+# Set of file roots when searching (equivalent to -I paths for the compiler).
+roots: Set[Path] = set()
+
+# Set of (canonical) file Path objects to exclude from inlining (and not only
+# exclude but to add a compiler error directive when they're encountered).
+excludes: Set[Path] = set()
+
+# Set of (canonical) file Path objects to keep as include directives.
+keeps: Set[Path] = set()
+
+# Whether to keep the #pragma once directives (unlikely, since this will result
+# in a warning, but the option is there).
+keep_pragma: bool = False
+
+# Destination file object (or stdout if no output file was supplied).
+destn: TextIO = sys.stdout
+
+# Set of file Path objects previously inlined (and to ignore if reencountering).
+found: Set[Path] = set()
+
+# Compiled regex Patern to handle "#pragma once" in various formats:
+# 
+#   #pragma once
+#     #pragma once
+#   #  pragma once
+#   #pragma   once
+#   #pragma once // comment
+# 
+# Ignoring commented versions, same as include_regex.
+# 
+pragma_regex: Pattern = re.compile(r'^\s*#\s*pragma\s*once\s*')
+
+# Compiled regex Patern to handle the following type of file includes:
+# 
+#   #include "file"
+#     #include "file"
+#   #  include "file"
+#   #include   "file"
+#   #include "file" // comment
+#   #include "file" // comment with quote "
+# 
+# And all combinations of, as well as ignoring the following:
+# 
+#   #include <file>
+#   //#include "file"
+#   /*#include "file"*/
+# 
+# We don't try to catch errors since the compiler will do this (and the code is
+# expected to be valid before processing) and we don't care what follows the
+# file (whether it's a valid comment or not, since anything after the quoted
+# string is ignored)
+# 
+include_regex: Pattern = re.compile(r'^\s*#\s*include\s*"(.+?)"')
+
+# Simple tests to prove include_regex's cases.
+# 
+def test_match_include() -> bool:
+    if (include_regex.match('#include "file"')   and
+        include_regex.match('  #include "file"') and
+        include_regex.match('#  include "file"') and
+        include_regex.match('#include   "file"') and
+        include_regex.match('#include "file" // comment')):
+            if (not include_regex.match('#include <file>')   and
+                not include_regex.match('//#include "file"') and
+                not include_regex.match('/*#include "file"*/')):
+                    found = include_regex.match('#include "file" // "')
+                    if (found and found.group(1) == 'file'):
+                        print('#include match valid')
+                        return True
+    return False
+
+# Simple tests to prove pragma_regex's cases.
+# 
+def test_match_pragma() -> bool:
+    if (pragma_regex.match('#pragma once')   and
+        pragma_regex.match('  #pragma once') and
+        pragma_regex.match('#  pragma once') and
+        pragma_regex.match('#pragma   once') and
+        pragma_regex.match('#pragma once // comment')):
+            if (not pragma_regex.match('//#pragma once') and
+                not pragma_regex.match('/*#pragma once*/')):
+                    print('#pragma once match valid')
+                    return True
+    return False
+
+# Finds 'file'. First the list of 'root' paths are searched, followed by the
+# the currently processing file's 'parent' path, returning a valid Path in
+# canonical form. If no match is found None is returned.
+# 
+def resolve_include(file: str, parent: Optional[Path] = None) -> Optional[Path]:
+    for root in roots:
+        found = root.joinpath(file).resolve()
+        if (found.is_file()):
+            return found
+    if (parent):
+        found = parent.joinpath(file).resolve();
+    else:
+        found = Path(file)
+    if (found.is_file()):
+        return found
+    return None
+
+# Helper to resolve lists of files. 'file_list' is passed in from the arguments
+# and each entry resolved to its canonical path (like any include entry, either
+# from the list of root paths or the owning file's 'parent', which in this case
+# is case is the input file). The results are stored in 'resolved'.
+# 
+def resolve_excluded_files(file_list: Optional[List[str]], resolved: Set[Path], parent: Optional[Path] = None) -> None:
+    if (file_list):
+        for filename in file_list:
+            found = resolve_include(filename, parent)
+            if (found):
+                resolved.add(found)
+            else:
+                error_line(f'Warning: excluded file not found: {filename}')
+
+# Writes 'line' to the open 'destn' (or stdout).
+# 
+def write_line(line: str) -> None:
+    print(line, file=destn)
+
+# Logs 'line' to stderr. This is also used for general notifications that we
+# don't want to go to stdout (so the source can be piped).
+# 
+def error_line(line: Any) -> None:
+    print(line, file=sys.stderr)
+
+# Inline the contents of 'file' (with any of its includes also inlined, etc.).
+# 
+# Note: text encoding errors are ignored and replaced with ? when reading the
+# input files. This isn't ideal, but it's more than likely in the comments than
+# code and a) the text editor has probably also failed to read the same content,
+# and b) the compiler probably did too.
+# 
+def add_file(file: Path, file_name: str = None) -> None:
+    if (file.is_file()):
+        if (not file_name):
+            file_name = file.name
+        error_line(f'Processing: {file_name}')
+        with file.open('r', errors='replace') as opened:
+            for line in opened:
+                line = line.rstrip('\n')
+                match_include = include_regex.match(line);
+                if (match_include):
+                    # We have a quoted include directive so grab the file
+                    inc_name = match_include.group(1)
+                    resolved = resolve_include(inc_name, file.parent)
+                    if (resolved):
+                        if (resolved in excludes):
+                            # The file was excluded so error if the compiler uses it
+                            write_line(f'#error Using excluded file: {inc_name} (re-amalgamate source to fix)')
+                            error_line(f'Excluding: {inc_name}')
+                        else:
+                            if (resolved not in found):
+                                # The file was not previously encountered
+                                found.add(resolved)
+                                if (resolved in keeps):
+                                    # But the include was flagged to keep as included
+                                    write_line(f'/**** *NOT* inlining {inc_name} ****/')
+                                    write_line(line)
+                                    error_line(f'Not inlining: {inc_name}')
+                                else:
+                                    # The file was neither excluded nor seen before so inline it
+                                    write_line(f'/**** start inlining {inc_name} ****/')
+                                    add_file(resolved, inc_name)
+                                    write_line(f'/**** ended inlining {inc_name} ****/')
+                            else:
+                                write_line(f'/**** skipping file: {inc_name} ****/')
+                    else:
+                        # The include file didn't resolve to a file
+                        write_line(f'#error Unable to find: {inc_name}')
+                        error_line(f'Error: Unable to find: {inc_name}')
+                else:
+                    # Skip any 'pragma once' directives, otherwise write the source line
+                    if (keep_pragma or not pragma_regex.match(line)):
+                        write_line(line)
+    else:
+        error_line(f'Error: Invalid file: {file}')
+
+# Start here
+parser = argparse.ArgumentParser(description='Amalgamate Tool', epilog=f'example: {sys.argv[0]} -r ../my/path -r ../other/path -o out.c in.c')
+parser.add_argument('-r', '--root', action='append', type=Path, help='file root search path')
+parser.add_argument('-x', '--exclude',  action='append', help='file to completely exclude from inlining')
+parser.add_argument('-k', '--keep', action='append', help='file to exclude from inlining but keep the include directive')
+parser.add_argument('-p', '--pragma', action='store_true', default=False, help='keep any "#pragma once" directives (removed by default)')
+parser.add_argument('-o', '--output', type=argparse.FileType('w'), help='output file (otherwise stdout)')
+parser.add_argument('input', type=Path, help='input file')
+args = parser.parse_args()
+
+# Fail early on an invalid input (and store it so we don't recurse)
+args.input = args.input.resolve(strict=True)
+found.add(args.input)
+
+# Resolve all of the root paths upfront (we'll halt here on invalid roots)
+if (args.root):
+    for path in args.root:
+        roots.add(path.resolve(strict=True))
+
+# The remaining params: so resolve the excluded files and #pragma once directive
+resolve_excluded_files(args.exclude, excludes, args.input.parent)
+resolve_excluded_files(args.keep,    keeps,    args.input.parent)
+keep_pragma = args.pragma;
+
+# Then recursively process the input file
+try:
+    if (args.output):
+        destn = args.output
+    add_file(args.input)
+finally:
+    if (destn):
+        destn.close()

build/single_file_libs/combine.sh

@@ -130,7 +130,7 @@ add_file() {
         local res_inc="$(resolve_include "$srcdir" "$inc")"
         if list_has_item "$XINCS" "$inc"; then
           # The file was excluded so error if the source attempts to use it
-          write_line "#error Using excluded file: $inc"
+          write_line "#error Using excluded file: $inc (re-amalgamate source to fix)"
           log_line "Excluding: $inc"
         else
           if ! list_has_item "$FOUND" "$res_inc"; then
@@ -200,6 +200,7 @@ if [ -n "$1" ]; then
       printf "" > "$DESTN"
     fi
     test_deps
+    log_line "Processing using the slower shell script; this might take a while"
     add_file "$1"
   else
     echo "Input file not found: \"$1\""

build/single_file_libs/create_single_file_decoder.sh

@@ -4,8 +4,13 @@
 ZSTD_SRC_ROOT="../../lib"
 
 # Amalgamate the sources
-echo "Amalgamating files... this can take a while"
-./combine.sh -r "$ZSTD_SRC_ROOT" -o zstddeclib.c zstddeclib-in.c
+echo "Amalgamating files..."
+# Using the faster Python script if we have 3.8 or higher
+if python3 -c 'import sys; assert sys.version_info >= (3,8)' 2>/dev/null; then
+  ./combine.py -r "$ZSTD_SRC_ROOT" -x legacy/zstd_legacy.h -o zstddeclib.c zstddeclib-in.c
+else
+  ./combine.sh -r "$ZSTD_SRC_ROOT" -x legacy/zstd_legacy.h -o zstddeclib.c zstddeclib-in.c
+fi
 # Did combining work?
 if [ $? -ne 0 ]; then
   echo "Combine script: FAILED"

build/single_file_libs/create_single_file_library.sh

@@ -4,8 +4,13 @@
 ZSTD_SRC_ROOT="../../lib"
 
 # Amalgamate the sources
-echo "Amalgamating files... this can take a while"
-./combine.sh -r "$ZSTD_SRC_ROOT" -o zstd.c zstd-in.c
+echo "Amalgamating files..."
+# Using the faster Python script if we have 3.8 or higher
+if python3 -c 'import sys; assert sys.version_info >= (3,8)' 2>/dev/null; then
+  ./combine.py -r "$ZSTD_SRC_ROOT" -x legacy/zstd_legacy.h -o zstd.c zstd-in.c
+else
+  ./combine.sh -r "$ZSTD_SRC_ROOT" -x legacy/zstd_legacy.h -o zstd.c zstd-in.c
+fi
 # Did combining work?
 if [ $? -ne 0 ]; then
   echo "Combine script: FAILED"

build/single_file_libs/zstd-in.c

@@ -4,11 +4,11 @@
  *
  * Generate using:
  * \code
- *	combine.sh -r ../../lib -o zstd.c zstd-in.c
+ *	python combine.py -r ../../lib -x legacy/zstd_legacy.h -o zstd.c zstd-in.c
  * \endcode
  */
 /*
- * Copyright (c) 2016-2021, Yann Collet, Facebook, Inc.
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
  * All rights reserved.
  *
  * This source code is licensed under both the BSD-style license (found in the
@@ -25,9 +25,13 @@
  * Note: MEM_MODULE stops xxhash redefining BYTE, U16, etc., which are also
  * defined in mem.h (breaking C99 compatibility).
  *
- * Note: the undefs for xxHash allow Zstd's implementation to coinside with with
+ * Note: the undefs for xxHash allow Zstd's implementation to coincide with with
  * standalone xxHash usage (with global defines).
  *
+ * Note: if you enable ZSTD_LEGACY_SUPPORT the combine.py script will need
+ * re-running without the "-x legacy/zstd_legacy.h" option (it excludes the
+ * legacy support at the source level).
+ *
  * Note: multithreading is enabled for all platforms apart from Emscripten.
  */
 #define DEBUGLEVEL 0
@@ -43,6 +47,8 @@
 #define ZSTD_MULTITHREAD
 #endif
 #define ZSTD_TRACE 0
+/* TODO: Can't amalgamate ASM function */
+#define ZSTD_DISABLE_ASM 1
 
 /* Include zstd_deps.h first with all the options we need enabled. */
 #define ZSTD_DEPS_NEED_MALLOC

build/single_file_libs/zstddeclib-in.c

@@ -4,11 +4,11 @@
  *
  * Generate using:
  * \code
- *	combine.sh -r ../../lib -o zstddeclib.c zstddeclib-in.c
+ *	python combine.py -r ../../lib -x legacy/zstd_legacy.h -o zstddeclib.c zstddeclib-in.c
  * \endcode
  */
 /*
- * Copyright (c) 2016-2021, Yann Collet, Facebook, Inc.
+ * Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
  * All rights reserved.
  *
  * This source code is licensed under both the BSD-style license (found in the
@@ -25,8 +25,12 @@
  * Note: MEM_MODULE stops xxhash redefining BYTE, U16, etc., which are also
  * defined in mem.h (breaking C99 compatibility).
  *
- * Note: the undefs for xxHash allow Zstd's implementation to coinside with with
+ * Note: the undefs for xxHash allow Zstd's implementation to coincide with with
  * standalone xxHash usage (with global defines).
+ *
+ * Note: if you enable ZSTD_LEGACY_SUPPORT the combine.py script will need
+ * re-running without the "-x legacy/zstd_legacy.h" option (it excludes the
+ * legacy support at the source level).
  */
 #define DEBUGLEVEL 0
 #define MEM_MODULE
@@ -39,6 +43,8 @@
 #define ZSTD_LEGACY_SUPPORT 0
 #define ZSTD_STRIP_ERROR_STRINGS
 #define ZSTD_TRACE 0
+/* TODO: Can't amalgamate ASM function */
+#define ZSTD_DISABLE_ASM 1
 
 /* Include zstd_deps.h first with all the options we need enabled. */
 #define ZSTD_DEPS_NEED_MALLOC

contrib/VS2005/zstd/zstd.vcproj

@@ -363,6 +363,10 @@
 				RelativePath="..\..\..\programs\fileio.c"
 				>
 			</File>
+			<File
+                RelativePath="..\..\..\programs\fileio_asyncio.c"
+                >
+            </File>
 			<File
 				RelativePath="..\..\..\lib\compress\fse_compress.c"
 				>

contrib/freestanding_lib/freestanding.py

@@ -27,7 +27,6 @@ SKIPPED_FILES = [
     "common/pool.h",
     "common/threading.c",
     "common/threading.h",
-    "common/zstd_trace.c",
     "common/zstd_trace.h",
     "compress/zstdmt_compress.h",
     "compress/zstdmt_compress.c",
@@ -461,7 +460,8 @@ class Freestanding(object):
         print(*args, **kwargs)
 
     def _copy_file(self, lib_path):
-        if not (lib_path.endswith(".c") or lib_path.endswith(".h")):
+        suffixes = [".c", ".h", ".S"]
+        if not any((lib_path.endswith(suffix) for suffix in suffixes)):
             return
         if lib_path in SKIPPED_FILES:
             self._log(f"\tSkipping file: {lib_path}")

contrib/linux-kernel/Makefile

@@ -35,11 +35,12 @@ libzstd:
 		-DXXH_STATIC_LINKING_ONLY \
 		-DMEM_FORCE_MEMORY_ACCESS=0 \
 		-D__GNUC__ \
+		-D__linux__=1 \
 		-DSTATIC_BMI2=0 \
 		-DZSTD_ADDRESS_SANITIZER=0 \
 		-DZSTD_MEMORY_SANITIZER=0 \
+		-DZSTD_DATAFLOW_SANITIZER=0 \
 		-DZSTD_COMPRESS_HEAPMODE=1 \
-		-UZSTD_NO_INLINE \
 		-UNO_PREFETCH \
 		-U__cplusplus \
 		-UZSTD_DLL_EXPORT \
@@ -50,9 +51,11 @@ libzstd:
 		-U_WIN32 \
 		-RZSTDLIB_VISIBILITY= \
 		-RZSTDERRORLIB_VISIBILITY= \
+		-RZSTD_FALLTHROUGH=fallthrough \
 		-DZSTD_HAVE_WEAK_SYMBOLS=0 \
 		-DZSTD_TRACE=0 \
-		-DZSTD_NO_TRACE
+		-DZSTD_NO_TRACE \
+		-DZSTD_LINUX_KERNEL
 	mv linux/lib/zstd/zstd.h linux/include/linux/zstd_lib.h
 	mv linux/lib/zstd/zstd_errors.h linux/include/linux/
 	cp linux_zstd.h linux/include/linux/zstd.h
@@ -86,10 +89,17 @@ import-upstream:
 	rm $(LINUX)/lib/zstd/common/xxhash.*
 	rm $(LINUX)/lib/zstd/compress/zstdmt_*
 
+DEBUGFLAGS= -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
+            -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
+            -Wstrict-prototypes -Wundef -Wpointer-arith \
+            -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings \
+            -Wredundant-decls -Wmissing-prototypes -Wc++-compat \
+	    -Wimplicit-fallthrough
+
 .PHONY: test
 test: libzstd
-	$(MAKE) -C test run-test CFLAGS="-O3 $(CFLAGS)" -j
+	$(MAKE) -C test run-test CFLAGS="-O3 $(CFLAGS) $(DEBUGFLAGS) -Werror" -j
 
 .PHONY: clean
 clean:
-	$(RM) -rf linux
+	$(RM) -rf linux test/test test/static_test

contrib/linux-kernel/decompress_sources.h

@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
 /*
  * Copyright (c) Facebook, Inc.
  * All rights reserved.
@@ -16,6 +16,12 @@
  * decompression.
  */
 
+/*
+ * Disable the ASM Huffman implementation because we need to
+ * include all the sources.
+ */
+#define ZSTD_DISABLE_ASM 1
+
 #include "common/debug.c"
 #include "common/entropy_common.c"
 #include "common/error_private.c"

contrib/linux-kernel/linux.mk

@@ -1,4 +1,4 @@
-# SPDX-License-Identifier: GPL-2.0-only
+# SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
 # ################################################################
 # Copyright (c) Facebook, Inc.
 # All rights reserved.
@@ -11,7 +11,7 @@
 obj-$(CONFIG_ZSTD_COMPRESS) += zstd_compress.o
 obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd_decompress.o
 
-ccflags-y += -O3
+ccflags-y += -Wno-error=deprecated-declarations
 
 zstd_compress-y := \
 		zstd_compress_module.o \
@@ -41,6 +41,7 @@ zstd_decompress-y := \
 		common/fse_decompress.o \
 		common/zstd_common.o \
 		decompress/huf_decompress.o \
+		decompress/huf_decompress_amd64.o \
 		decompress/zstd_ddict.o \
 		decompress/zstd_decompress.o \
 		decompress/zstd_decompress_block.o \

contrib/linux-kernel/linux_zstd.h

@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
 /*
  * Copyright (c) Yann Collet, Facebook, Inc.
  * All rights reserved.

contrib/linux-kernel/mem.h

@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
 /*
  * Copyright (c) Yann Collet, Facebook, Inc.
  * All rights reserved.
@@ -30,6 +30,8 @@
 *  Basic Types
 *****************************************************************/
 typedef uint8_t  BYTE;
+typedef uint8_t  U8;
+typedef int8_t   S8;
 typedef uint16_t U16;
 typedef int16_t  S16;
 typedef uint32_t U32;

contrib/linux-kernel/test/Makefile

@@ -18,9 +18,13 @@ CPPFLAGS += -DZSTD_ASAN_DONT_POISON_WORKSPACE
 LINUX_ZSTD_MODULE     := $(wildcard $(LINUX_ZSTDLIB)/*.c)
 LINUX_ZSTD_COMMON     := $(wildcard $(LINUX_ZSTDLIB)/common/*.c)
 LINUX_ZSTD_COMPRESS   := $(wildcard $(LINUX_ZSTDLIB)/compress/*.c)
-LINUX_ZSTD_DECOMPRESS := $(wildcard $(LINUX_ZSTDLIB)/decompress/*.c)
+LINUX_ZSTD_DECOMPRESS := $(wildcard $(LINUX_ZSTDLIB)/decompress/*.c $(LINUX_ZSTDLIB)/decompress/*.S)
 LINUX_ZSTD_FILES      := $(LINUX_ZSTD_MODULE) $(LINUX_ZSTD_COMMON) $(LINUX_ZSTD_COMPRESS) $(LINUX_ZSTD_DECOMPRESS)
-LINUX_ZSTD_OBJECTS    := $(LINUX_ZSTD_FILES:.c=.o)
+LINUX_ZSTD_OBJECTS0   := $(LINUX_ZSTD_FILES:.c=.o)
+LINUX_ZSTD_OBJECTS    := $(LINUX_ZSTD_OBJECTS0:.S=.o)
+
+%.o: %.S
+	$(COMPILE.S) $(OUTPUT_OPTION) $<
 
 liblinuxzstd.a: $(LINUX_ZSTD_OBJECTS)
 	$(AR) $(ARFLAGS) $@ $^

contrib/linux-kernel/test/include/asm/unaligned.h

@@ -20,6 +20,7 @@ static unsigned _isLittleEndian(void)
 {
     const union { uint32_t u; uint8_t c[4]; } one = { 1 };
     assert(_IS_LITTLE_ENDIAN == one.c[0]);
+    (void)one;
     return _IS_LITTLE_ENDIAN;
 }
 

contrib/linux-kernel/test/include/linux/compiler.h

@@ -18,4 +18,6 @@
 #define noinline __attribute__((noinline))
 #endif
 
+#define fallthrough __attribute__((__fallthrough__))
+
 #endif

contrib/linux-kernel/test/include/linux/xxhash.h

@@ -124,11 +124,10 @@ XXH_API uint64_t xxh64(const void *input, size_t length, uint64_t seed);
 static inline unsigned long xxhash(const void *input, size_t length,
 				   uint64_t seed)
 {
-#if BITS_PER_LONG == 64
-       return xxh64(input, length, seed);
-#else
-       return xxh32(input, length, seed);
-#endif
+	if (sizeof(size_t) == 8)
+		return xxh64(input, length, seed);
+	else
+		return xxh32(input, length, seed);
 }
 
 /*-****************************

contrib/linux-kernel/test/macro-test.sh

@@ -36,9 +36,9 @@ test_not_present "ZSTD_NO_INTRINSICS"
 test_not_present "ZSTD_NO_UNUSED_FUNCTIONS"
 test_not_present "ZSTD_LEGACY_SUPPORT"
 test_not_present "STATIC_BMI2"
-test_not_present "ZSTD_NO_INLINE"
 test_not_present "ZSTD_DLL_EXPORT"
 test_not_present "ZSTD_DLL_IMPORT"
 test_not_present "__ICCARM__"
 test_not_present "_MSC_VER"
 test_not_present "_WIN32"
+test_not_present "__linux__"

contrib/linux-kernel/test/static_test.c

@@ -28,17 +28,19 @@ static const char kEmptyZstdFrame[] = {
     0x28, 0xb5, 0x2f, 0xfd, 0x24, 0x00, 0x01, 0x00, 0x00, 0x99, 0xe9, 0xd8, 0x51
 };
 
-static void test_decompress_unzstd() {
+static void test_decompress_unzstd(void) {
     fprintf(stderr, "Testing decompress unzstd... ");
     {
         size_t const wkspSize = zstd_dctx_workspace_bound();
         void* wksp = malloc(wkspSize);
-        CONTROL(wksp != NULL);
         ZSTD_DCtx* dctx = zstd_init_dctx(wksp, wkspSize);
+        CONTROL(wksp != NULL);
         CONTROL(dctx != NULL);
-        size_t const dSize = zstd_decompress_dctx(dctx, NULL, 0, kEmptyZstdFrame, sizeof(kEmptyZstdFrame));
-        CONTROL(!zstd_is_error(dSize));
-        CONTROL(dSize == 0);
+        {
+          size_t const dSize = zstd_decompress_dctx(dctx, NULL, 0, kEmptyZstdFrame, sizeof(kEmptyZstdFrame));
+          CONTROL(!zstd_is_error(dSize));
+          CONTROL(dSize == 0);
+        }
         free(wksp);
     }
     fprintf(stderr, "Ok\n");

contrib/linux-kernel/test/test.c

@@ -30,15 +30,15 @@ typedef struct {
   size_t compSize;
 } test_data_t;
 
-test_data_t create_test_data(void) {
+static test_data_t create_test_data(void) {
   test_data_t data;
   data.dataSize = 128 * 1024;
-  data.data = malloc(data.dataSize);
+  data.data = (char*)malloc(data.dataSize);
   CONTROL(data.data != NULL);
-  data.data2 = malloc(data.dataSize);
+  data.data2 = (char*)malloc(data.dataSize);
   CONTROL(data.data2 != NULL);
   data.compSize = zstd_compress_bound(data.dataSize);
-  data.comp = malloc(data.compSize);
+  data.comp = (char*)malloc(data.compSize);
   CONTROL(data.comp != NULL);
   memset(data.data, 0, data.dataSize);
   return data;
@@ -54,26 +54,27 @@ static void free_test_data(test_data_t const *data) {
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
 
 static void test_btrfs(test_data_t const *data) {
-  fprintf(stderr, "testing btrfs use cases... ");
   size_t const size = MIN(data->dataSize, 128 * 1024);
+  fprintf(stderr, "testing btrfs use cases... ");
   for (int level = -1; level < 16; ++level) {
     zstd_parameters params = zstd_get_params(level, size);
-    CONTROL(params.cParams.windowLog <= 17);
     size_t const workspaceSize =
         MAX(zstd_cstream_workspace_bound(&params.cParams),
             zstd_dstream_workspace_bound(size));
     void *workspace = malloc(workspaceSize);
-    CONTROL(workspace != NULL);
 
     char const *ip = data->data;
     char const *iend = ip + size;
     char *op = data->comp;
     char *oend = op + data->compSize;
+
+    CONTROL(params.cParams.windowLog <= 17);
+    CONTROL(workspace != NULL);
     {
       zstd_cstream *cctx = zstd_init_cstream(&params, size, workspace, workspaceSize);
-      CONTROL(cctx != NULL);
       zstd_out_buffer out = {NULL, 0, 0};
       zstd_in_buffer in = {NULL, 0, 0};
+      CONTROL(cctx != NULL);
       for (;;) {
         if (in.pos == in.size) {
           in.src = ip;
@@ -108,9 +109,9 @@ static void test_btrfs(test_data_t const *data) {
     oend = op + size;
     {
       zstd_dstream *dctx = zstd_init_dstream(1ULL << params.cParams.windowLog, workspace, workspaceSize);
-      CONTROL(dctx != NULL);
       zstd_out_buffer out = {NULL, 0, 0};
       zstd_in_buffer in = {NULL, 0, 0};
+      CONTROL(dctx != NULL);
       for (;;) {
         if (in.pos == in.size) {
           in.src = ip;
@@ -125,15 +126,16 @@ static void test_btrfs(test_data_t const *data) {
           out.pos = 0;
           op += out.size;
         }
-
-        size_t const ret = zstd_decompress_stream(dctx, &out, &in);
-        CONTROL(!zstd_is_error(ret));
-        if (ret == 0) {
-          break;
+        {
+          size_t const ret = zstd_decompress_stream(dctx, &out, &in);
+          CONTROL(!zstd_is_error(ret));
+          if (ret == 0) {
+            break;
+          }
         }
       }
     }
-    CONTROL(op - data->data2 == data->dataSize);
+    CONTROL((size_t)(op - data->data2) == data->dataSize);
     CONTROL(!memcmp(data->data, data->data2, data->dataSize));
     free(workspace);
   }
@@ -141,14 +143,14 @@ static void test_btrfs(test_data_t const *data) {
 }
 
 static void test_decompress_unzstd(test_data_t const *data) {
-    fprintf(stderr, "Testing decompress unzstd... ");
     size_t cSize;
+    fprintf(stderr, "Testing decompress unzstd... ");
     {
         zstd_parameters params = zstd_get_params(19, 0);
         size_t const wkspSize = zstd_cctx_workspace_bound(&params.cParams);
         void* wksp = malloc(wkspSize);
-        CONTROL(wksp != NULL);
         zstd_cctx* cctx = zstd_init_cctx(wksp, wkspSize);
+        CONTROL(wksp != NULL);
         CONTROL(cctx != NULL);
         cSize = zstd_compress_cctx(cctx, data->comp, data->compSize, data->data, data->dataSize, &params);
         CONTROL(!zstd_is_error(cSize));
@@ -157,19 +159,21 @@ static void test_decompress_unzstd(test_data_t const *data) {
     {
         size_t const wkspSize = zstd_dctx_workspace_bound();
         void* wksp = malloc(wkspSize);
-        CONTROL(wksp != NULL);
         zstd_dctx* dctx = zstd_init_dctx(wksp, wkspSize);
+        CONTROL(wksp != NULL);
         CONTROL(dctx != NULL);
-        size_t const dSize = zstd_decompress_dctx(dctx, data->data2, data->dataSize, data->comp, cSize);
-        CONTROL(!zstd_is_error(dSize));
-        CONTROL(dSize == data->dataSize);
+        {
+          size_t const dSize = zstd_decompress_dctx(dctx, data->data2, data->dataSize, data->comp, cSize);
+          CONTROL(!zstd_is_error(dSize));
+          CONTROL(dSize == data->dataSize);
+        }
         CONTROL(!memcmp(data->data, data->data2, data->dataSize));
         free(wksp);
     }
     fprintf(stderr, "Ok\n");
 }
 
-static void test_f2fs() {
+static void test_f2fs(void) {
   fprintf(stderr, "testing f2fs uses... ");
   CONTROL(zstd_min_clevel() < 0);
   CONTROL(zstd_max_clevel() == 22);
@@ -182,7 +186,7 @@ static void __attribute__((noinline)) use(void *x) {
   asm volatile("" : "+r"(x));
 }
 
-static void __attribute__((noinline)) set_stack() {
+static void __attribute__((noinline)) set_stack(void) {
 
   char stack[8192];
   g_stack = stack;
@@ -190,14 +194,16 @@ static void __attribute__((noinline)) set_stack() {
   use(g_stack);
 }
 
-static void __attribute__((noinline)) check_stack() {
+static void __attribute__((noinline)) check_stack(void) {
   size_t cleanStack = 0;
   while (cleanStack < 8192 && g_stack[cleanStack] == 0x33) {
     ++cleanStack;
   }
-  size_t const stackSize = 8192 - cleanStack;
-  fprintf(stderr, "Maximum stack size: %zu\n", stackSize);
-  CONTROL(stackSize <= 2048 + 512);
+  {
+    size_t const stackSize = 8192 - cleanStack;
+    fprintf(stderr, "Maximum stack size: %zu\n", stackSize);
+    CONTROL(stackSize <= 2048 + 512);
+  }
 }
 
 static void test_stack_usage(test_data_t const *data) {

contrib/linux-kernel/zstd_compress_module.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
 /*
  * Copyright (c) Facebook, Inc.
  * All rights reserved.
@@ -17,6 +17,43 @@
 #include "common/zstd_deps.h"
 #include "common/zstd_internal.h"
 
+#define ZSTD_FORWARD_IF_ERR(ret)            \
+	do {                                \
+		size_t const __ret = (ret); \
+		if (ZSTD_isError(__ret))    \
+			return __ret;       \
+	} while (0)
+
+static size_t zstd_cctx_init(zstd_cctx *cctx, const zstd_parameters *parameters,
+	unsigned long long pledged_src_size)
+{
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_reset(
+		cctx, ZSTD_reset_session_and_parameters));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setPledgedSrcSize(
+		cctx, pledged_src_size));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_windowLog, parameters->cParams.windowLog));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_hashLog, parameters->cParams.hashLog));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_chainLog, parameters->cParams.chainLog));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_searchLog, parameters->cParams.searchLog));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_minMatch, parameters->cParams.minMatch));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_targetLength, parameters->cParams.targetLength));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_strategy, parameters->cParams.strategy));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_contentSizeFlag, parameters->fParams.contentSizeFlag));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_checksumFlag, parameters->fParams.checksumFlag));
+	ZSTD_FORWARD_IF_ERR(ZSTD_CCtx_setParameter(
+		cctx, ZSTD_c_dictIDFlag, !parameters->fParams.noDictIDFlag));
+	return 0;
+}
+
 int zstd_min_clevel(void)
 {
 	return ZSTD_minCLevel();
@@ -59,7 +96,8 @@ EXPORT_SYMBOL(zstd_init_cctx);
 size_t zstd_compress_cctx(zstd_cctx *cctx, void *dst, size_t dst_capacity,
 	const void *src, size_t src_size, const zstd_parameters *parameters)
 {
-	return ZSTD_compress_advanced(cctx, dst, dst_capacity, src, src_size, NULL, 0, *parameters);
+	ZSTD_FORWARD_IF_ERR(zstd_cctx_init(cctx, parameters, src_size));
+	return ZSTD_compress2(cctx, dst, dst_capacity, src, src_size);
 }
 EXPORT_SYMBOL(zstd_compress_cctx);
 
@@ -73,7 +111,6 @@ zstd_cstream *zstd_init_cstream(const zstd_parameters *parameters,
 	unsigned long long pledged_src_size, void *workspace, size_t workspace_size)
 {
 	zstd_cstream *cstream;
-	size_t ret;
 
 	if (workspace == NULL)
 		return NULL;
@@ -86,8 +123,7 @@ zstd_cstream *zstd_init_cstream(const zstd_parameters *parameters,
 	if (pledged_src_size == 0)
 		pledged_src_size = ZSTD_CONTENTSIZE_UNKNOWN;
 
-	ret = ZSTD_initCStream_advanced(cstream, NULL, 0, *parameters, pledged_src_size);
-	if (ZSTD_isError(ret))
+	if (ZSTD_isError(zstd_cctx_init(cstream, parameters, pledged_src_size)))
 		return NULL;
 
 	return cstream;

contrib/linux-kernel/zstd_decompress_module.c

@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
 /*
  * Copyright (c) Facebook, Inc.
  * All rights reserved.

contrib/linux-kernel/zstd_deps.h

@@ -1,4 +1,4 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
+/* SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause */
 /*
  * Copyright (c) Facebook, Inc.
  * All rights reserved.

contrib/pzstd/Makefile

@@ -57,19 +57,6 @@ LD_COMMAND  = $(CXX) $^          $(ALL_LDFLAGS) $(LIBS) -pthread -o $@
 CC_COMMAND  = $(CC)  $(DEPFLAGS) $(ALL_CFLAGS)   -c $<  -o $@
 CXX_COMMAND = $(CXX) $(DEPFLAGS) $(ALL_CXXFLAGS) -c $<  -o $@
 
-# Get a list of all zstd files so we rebuild the static library when we need to
-ZSTDCOMMON_FILES := $(wildcard $(ZSTDDIR)/common/*.c) \
-                    $(wildcard $(ZSTDDIR)/common/*.h)
-ZSTDCOMP_FILES   := $(wildcard $(ZSTDDIR)/compress/*.c) \
-                    $(wildcard $(ZSTDDIR)/compress/*.h)
-ZSTDDECOMP_FILES := $(wildcard $(ZSTDDIR)/decompress/*.c) \
-                    $(wildcard $(ZSTDDIR)/decompress/*.h)
-ZSTDPROG_FILES   := $(wildcard $(PROGDIR)/*.c) \
-                    $(wildcard $(PROGDIR)/*.h)
-ZSTD_FILES       := $(wildcard $(ZSTDDIR)/*.h) \
-                    $(ZSTDDECOMP_FILES) $(ZSTDCOMMON_FILES) $(ZSTDCOMP_FILES) \
-                    $(ZSTDPROG_FILES)
-
 # List all the pzstd source files so we can determine their dependencies
 PZSTD_SRCS  := $(wildcard *.cpp)
 PZSTD_TESTS := $(wildcard test/*.cpp)
@@ -189,7 +176,8 @@ roundtrip: test/RoundTripTest$(EXT)
 
 # Use the static library that zstd builds for simplicity and
 # so we get the compiler options correct
-$(ZSTDDIR)/libzstd.a: $(ZSTD_FILES)
+.PHONY: $(ZSTDDIR)/libzstd.a
+$(ZSTDDIR)/libzstd.a:
 	CFLAGS="$(ALL_CFLAGS)" LDFLAGS="$(ALL_LDFLAGS)" $(MAKE) -C $(ZSTDDIR) libzstd.a
 
 # Rules to build the tests

contrib/pzstd/Options.cpp

@@ -87,7 +87,7 @@ void usage() {
   std::fprintf(stderr, "  -V, --version          : display version number and exit\n");
   std::fprintf(stderr, "  -v, --verbose          : verbose mode; specify multiple times to increase log level (default:2)\n");
   std::fprintf(stderr, "  -q, --quiet            : suppress warnings; specify twice to suppress errors too\n");
-  std::fprintf(stderr, "  -c, --stdout           : force write to standard output, even if it is the console\n");
+  std::fprintf(stderr, "  -c, --stdout           : write to standard output (even if it is the console)\n");
 #ifdef UTIL_HAS_CREATEFILELIST
   std::fprintf(stderr, "  -r                     : operate recursively on directories\n");
 #endif

contrib/pzstd/Options.h

@@ -9,6 +9,9 @@
 #pragma once
 
 #define ZSTD_STATIC_LINKING_ONLY
+#define ZSTD_DISABLE_DEPRECATE_WARNINGS /* No deprecation warnings, pzstd itself is deprecated
+                                         * and uses deprecated functions
+                                         */
 #include "zstd.h"
 #undef ZSTD_STATIC_LINKING_ONLY
 

contrib/pzstd/Pzstd.h

@@ -17,6 +17,9 @@
 #include "utils/ThreadPool.h"
 #include "utils/WorkQueue.h"
 #define ZSTD_STATIC_LINKING_ONLY
+#define ZSTD_DISABLE_DEPRECATE_WARNINGS /* No deprecation warnings, pzstd itself is deprecated
+                                         * and uses deprecated functions
+                                         */
 #include "zstd.h"
 #undef ZSTD_STATIC_LINKING_ONLY
 

contrib/pzstd/utils/Buffer.h

@@ -45,7 +45,7 @@ class Buffer {
       : buffer_(buffer), range_(data) {}
 
   Buffer(Buffer&&) = default;
-  Buffer& operator=(Buffer&&) & = default;
+  Buffer& operator=(Buffer&&) = default;
 
   /**
    * Splits the data into two pieces: [begin, begin + n), [begin + n, end).

contrib/pzstd/utils/Range.h

@@ -6,7 +6,7 @@
  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
  * in the COPYING file in the root directory of this source tree).
  */
- 
+
 /**
  * A subset of `folly/Range.h`.
  * All code copied verbatim modulo formatting
@@ -83,8 +83,8 @@ class Range {
   Range(const Range&) = default;
   Range(Range&&) = default;
 
-  Range& operator=(const Range&) & = default;
-  Range& operator=(Range&&) & = default;
+  Range& operator=(const Range&) = default;
+  Range& operator=(Range&&) = default;
 
   constexpr size_type size() const {
     return e_ - b_;

contrib/seekable_format/zstdseek_decompress.c

@@ -23,13 +23,64 @@
 #  endif
 #endif
 
+/* ************************************************************
+*  Detect POSIX version
+*  PLATFORM_POSIX_VERSION = 0 for non-Unix e.g. Windows
+*  PLATFORM_POSIX_VERSION = 1 for Unix-like but non-POSIX
+*  PLATFORM_POSIX_VERSION > 1 is equal to found _POSIX_VERSION
+*  Value of PLATFORM_POSIX_VERSION can be forced on command line
+***************************************************************/
+#ifndef PLATFORM_POSIX_VERSION
+
+#  if (defined(__APPLE__) && defined(__MACH__)) || defined(__SVR4) || defined(_AIX) || defined(__hpux) /* POSIX.1-2001 (SUSv3) conformant */ \
+     || defined(__DragonFly__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__)  /* BSD distros */
+     /* exception rule : force posix version to 200112L,
+      * note: it's better to use unistd.h's _POSIX_VERSION whenever possible */
+#    define PLATFORM_POSIX_VERSION 200112L
+
+/* try to determine posix version through official unistd.h's _POSIX_VERSION (http://pubs.opengroup.org/onlinepubs/7908799/xsh/unistd.h.html).
+ * note : there is no simple way to know in advance if <unistd.h> is present or not on target system,
+ * Posix specification mandates its presence and its content, but target system must respect this spec.
+ * It's necessary to _not_ #include <unistd.h> whenever target OS is not unix-like
+ * otherwise it will block preprocessing stage.
+ * The following list of build macros tries to "guess" if target OS is likely unix-like, and therefore can #include <unistd.h>
+ */
+#  elif !defined(_WIN32) \
+     && ( defined(__unix__) || defined(__unix) \
+       || defined(__midipix__) || defined(__VMS) || defined(__HAIKU__) )
+
+#    if defined(__linux__) || defined(__linux) || defined(__CYGWIN__)
+#      ifndef _POSIX_C_SOURCE
+#        define _POSIX_C_SOURCE 200809L  /* feature test macro : https://www.gnu.org/software/libc/manual/html_node/Feature-Test-Macros.html */
+#      endif
+#    endif
+#    include <unistd.h>  /* declares _POSIX_VERSION */
+#    if defined(_POSIX_VERSION)  /* POSIX compliant */
+#      define PLATFORM_POSIX_VERSION _POSIX_VERSION
+#    else
+#      define PLATFORM_POSIX_VERSION 1
+#    endif
+
+#    ifdef __UCLIBC__
+#     ifndef __USE_MISC
+#      define __USE_MISC /* enable st_mtim on uclibc */
+#     endif
+#    endif
+
+#  else  /* non-unix target platform (like Windows) */
+#    define PLATFORM_POSIX_VERSION 0
+#  endif
+
+#endif   /* PLATFORM_POSIX_VERSION */
+
+
 /* ************************************************************
 * Avoid fseek()'s 2GiB barrier with MSVC, macOS, *BSD, MinGW
 ***************************************************************/
 #if defined(_MSC_VER) && _MSC_VER >= 1400
 #   define LONG_SEEK _fseeki64
 #elif !defined(__64BIT__) && (PLATFORM_POSIX_VERSION >= 200112L) /* No point defining Large file for 64 bit */
-#  define LONG_SEEK fseeko
+#   define LONG_SEEK fseeko
 #elif defined(__MINGW32__) && !defined(__STRICT_ANSI__) && !defined(__NO_MINGW_LFS) && defined(__MSVCRT__)
 #   define LONG_SEEK fseeko64
 #elif defined(_WIN32) && !defined(__DJGPP__)

doc/educational_decoder/zstd_decompress.c

@@ -2145,7 +2145,7 @@ static void FSE_init_dtable(FSE_dtable *const dtable,
 
     // "All remaining symbols are sorted in their natural order. Starting from
     // symbol 0 and table position 0, each symbol gets attributed as many cells
-    // as its probability. Cell allocation is spreaded, not linear."
+    // as its probability. Cell allocation is spread, not linear."
     // Place the rest in the table
     const u16 step = (size >> 1) + (size >> 3) + 3;
     const u16 mask = size - 1;

doc/zstd_compression_format.md

@@ -1124,7 +1124,7 @@ These symbols define a full state reset, reading `Accuracy_Log` bits.
 Then, all remaining symbols, sorted in natural order, are allocated cells.
 Starting from symbol `0` (if it exists), and table position `0`,
 each symbol gets allocated as many cells as its probability.
-Cell allocation is spreaded, not linear :
+Cell allocation is spread, not linear :
 each successor position follows this rule :
 
 ```
@@ -1669,7 +1669,7 @@ or at least provide a meaningful error code explaining for which reason it canno
 
 Version changes
 ---------------
-- 0.3.7 : clarifications for Repeat_Offsets
+- 0.3.7 : clarifications for Repeat_Offsets, matching RFC8878
 - 0.3.6 : clarifications for Dictionary_ID
 - 0.3.5 : clarifications for Block_Maximum_Size
 - 0.3.4 : clarifications for FSE decoding table

doc/zstd_manual.html

@@ -1,10 +1,10 @@
 <html>
 <head>
 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
-<title>zstd 1.5.0 Manual</title>
+<title>zstd 1.5.2 Manual</title>
 </head>
 <body>
-<h1>zstd 1.5.0 Manual</h1>
+<h1>zstd 1.5.2 Manual</h1>
 <hr>
 <a name="Contents"></a><h2>Contents</h2>
 <ol>
@@ -357,7 +357,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
      * ZSTD_c_stableOutBuffer
      * ZSTD_c_blockDelimiters
      * ZSTD_c_validateSequences
-     * ZSTD_c_splitBlocks
+     * ZSTD_c_useBlockSplitter
      * ZSTD_c_useRowMatchFinder
      * Because they are not stable, it's necessary to define ZSTD_STATIC_LINKING_ONLY to access them.
      * note : never ever use experimentalParam? names directly;
@@ -803,7 +803,7 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
 
 <a name="Chapter13"></a><h2>Advanced dictionary and prefix API (Requires v1.4.0+)</h2><pre>
  This API allows dictionaries to be used with ZSTD_compress2(),
- ZSTD_compressStream2(), and ZSTD_decompress(). Dictionaries are sticky, and
+ ZSTD_compressStream2(), and ZSTD_decompressDCtx(). Dictionaries are sticky, and
  only reset with the context is reset with ZSTD_reset_parameters or
  ZSTD_reset_session_and_parameters. Prefixes are single-use.
 <BR></pre>
@@ -1072,14 +1072,18 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
 } ZSTD_literalCompressionMode_e;
 </b></pre><BR>
 <pre><b>typedef enum {
-  ZSTD_urm_auto = 0,                   </b>/* Automatically determine whether or not we use row matchfinder */<b>
-  ZSTD_urm_disableRowMatchFinder = 1,  </b>/* Never use row matchfinder */<b>
-  ZSTD_urm_enableRowMatchFinder = 2    </b>/* Always use row matchfinder when applicable */<b>
-} ZSTD_useRowMatchFinderMode_e;
+  </b>/* Note: This enum controls features which are conditionally beneficial. Zstd typically will make a final<b>
+   * decision on whether or not to enable the feature (ZSTD_ps_auto), but setting the switch to ZSTD_ps_enable
+   * or ZSTD_ps_disable allow for a force enable/disable the feature.
+   */
+  ZSTD_ps_auto = 0,         </b>/* Let the library automatically determine whether the feature shall be enabled */<b>
+  ZSTD_ps_enable = 1,       </b>/* Force-enable the feature */<b>
+  ZSTD_ps_disable = 2       </b>/* Do not use the feature */<b>
+} ZSTD_paramSwitch_e;
 </b></pre><BR>
 <a name="Chapter15"></a><h2>Frame size functions</h2><pre></pre>
 
-<pre><b>unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
+<pre><b>ZSTDLIB_STATIC_API unsigned long long ZSTD_findDecompressedSize(const void* src, size_t srcSize);
 </b><p>  `src` should point to the start of a series of ZSTD encoded and/or skippable frames
   `srcSize` must be the _exact_ size of this series
        (i.e. there should be a frame boundary at `src + srcSize`)
@@ -1102,7 +1106,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
             however it does mean that all frame data must be present and valid. 
 </p></pre><BR>
 
-<pre><b>unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize);
+<pre><b>ZSTDLIB_STATIC_API unsigned long long ZSTD_decompressBound(const void* src, size_t srcSize);
 </b><p>  `src` should point to the start of a series of ZSTD encoded and/or skippable frames
   `srcSize` must be the _exact_ size of this series
        (i.e. there should be a frame boundary at `src + srcSize`)
@@ -1117,7 +1121,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_frameHeaderSize(const void* src, size_t srcSize);
 </b><p>  srcSize must be >= ZSTD_FRAMEHEADERSIZE_PREFIX.
  @return : size of the Frame Header,
            or an error code (if srcSize is too small) 
@@ -1144,7 +1148,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_mergeBlockDelimiters(ZSTD_Sequence* sequences, size_t seqsSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_mergeBlockDelimiters(ZSTD_Sequence* sequences, size_t seqsSize);
 </b><p> Given an array of ZSTD_Sequence, remove all sequences that represent block delimiters/last literals
  by merging them into into the literals of the next sequence.
 
@@ -1157,10 +1161,12 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_compressSequences(ZSTD_CCtx* const cctx, void* dst, size_t dstSize,
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_compressSequences(ZSTD_CCtx* const cctx, void* dst, size_t dstSize,
                       const ZSTD_Sequence* inSeqs, size_t inSeqsSize,
                       const void* src, size_t srcSize);
-</b><p> Compress an array of ZSTD_Sequence, generated from the original source buffer, into dst.
+</b><p> Compress an array of ZSTD_Sequence, associted with @src buffer, into dst.
+ @src contains the entire input (not just the literals).
+ If @srcSize > sum(sequence.length), the remaining bytes are considered all literals
  If a dictionary is included, then the cctx should reference the dict. (see: ZSTD_CCtx_refCDict(), ZSTD_CCtx_loadDictionary(), etc.)
  The entire source is compressed into a single frame.
 
@@ -1189,7 +1195,7 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_writeSkippableFrame(void* dst, size_t dstCapacity,
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_writeSkippableFrame(void* dst, size_t dstCapacity,
                                 const void* src, size_t srcSize, unsigned magicVariant);
 </b><p> Generates a zstd skippable frame containing data given by src, and writes it to dst buffer.
 
@@ -1205,12 +1211,31 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
  
 </p></pre><BR>
 
+<pre><b>size_t ZSTD_readSkippableFrame(void* dst, size_t dstCapacity, unsigned* magicVariant,
+                                const void* src, size_t srcSize);
+</b><p> Retrieves a zstd skippable frame containing data given by src, and writes it to dst buffer.
+
+ The parameter magicVariant will receive the magicVariant that was supplied when the frame was written,
+ i.e. magicNumber - ZSTD_MAGIC_SKIPPABLE_START.  This can be NULL if the caller is not interested
+ in the magicVariant.
+
+ Returns an error if destination buffer is not large enough, or if the frame is not skippable.
+
+ @return : number of bytes written or a ZSTD error.
+ 
+</p></pre><BR>
+
+<pre><b>unsigned ZSTD_isSkippableFrame(const void* buffer, size_t size);
+</b><p>  Tells if the content of `buffer` starts with a valid Frame Identifier for a skippable frame.
+ 
+</p></pre><BR>
+
 <a name="Chapter16"></a><h2>Memory management</h2><pre></pre>
 
-<pre><b>size_t ZSTD_estimateCCtxSize(int compressionLevel);
-size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams);
-size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params);
-size_t ZSTD_estimateDCtxSize(void);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize(int compressionLevel);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCParams(ZSTD_compressionParameters cParams);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateCCtxSize_usingCCtxParams(const ZSTD_CCtx_params* params);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateDCtxSize(void);
 </b><p>  These functions make it possible to estimate memory usage
   of a future {D,C}Ctx, before its creation.
 
@@ -1235,11 +1260,11 @@ size_t ZSTD_estimateDCtxSize(void);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_estimateCStreamSize(int compressionLevel);
-size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams);
-size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params);
-size_t ZSTD_estimateDStreamSize(size_t windowSize);
-size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize(int compressionLevel);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCParams(ZSTD_compressionParameters cParams);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateCStreamSize_usingCCtxParams(const ZSTD_CCtx_params* params);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize(size_t windowSize);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
 </b><p>  ZSTD_estimateCStreamSize() will provide a budget large enough for any compression level up to selected one.
   It will also consider src size to be arbitrarily "large", which is worst case.
   If srcSize is known to always be small, ZSTD_estimateCStreamSize_usingCParams() can provide a tighter estimation.
@@ -1254,17 +1279,17 @@ size_t ZSTD_estimateDStreamSize_fromFrame(const void* src, size_t srcSize);
          In this case, get total size by adding ZSTD_estimate?DictSize 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
-size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, ZSTD_dictLoadMethod_e dictLoadMethod);
-size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize(size_t dictSize, int compressionLevel);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateCDictSize_advanced(size_t dictSize, ZSTD_compressionParameters cParams, ZSTD_dictLoadMethod_e dictLoadMethod);
+ZSTDLIB_STATIC_API size_t ZSTD_estimateDDictSize(size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod);
 </b><p>  ZSTD_estimateCDictSize() will bet that src size is relatively "small", and content is copied, like ZSTD_createCDict().
   ZSTD_estimateCDictSize_advanced() makes it possible to control compression parameters precisely, like ZSTD_createCDict_advanced().
   Note : dictionaries created by reference (`ZSTD_dlm_byRef`) are logically smaller.
  
 </p></pre><BR>
 
-<pre><b>ZSTD_CCtx*    ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
-ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticCCtx() */<b>
+<pre><b>ZSTDLIB_STATIC_API ZSTD_CCtx*    ZSTD_initStaticCCtx(void* workspace, size_t workspaceSize);
+ZSTDLIB_STATIC_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticCCtx() */<b>
 </b><p>  Initialize an object using a pre-allocated fixed-size buffer.
   workspace: The memory area to emplace the object into.
              Provided pointer *must be 8-bytes aligned*.
@@ -1287,7 +1312,7 @@ ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspaceSize);
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticDCtx() */<b>
+<pre><b>ZSTDLIB_STATIC_API ZSTD_DStream* ZSTD_initStaticDStream(void* workspace, size_t workspaceSize);    </b>/**< same as ZSTD_initStaticDCtx() */<b>
 </b></pre><BR>
 <pre><b>typedef void* (*ZSTD_allocFunction) (void* opaque, size_t size);
 typedef void  (*ZSTD_freeFunction) (void* opaque, void* address);
@@ -1303,9 +1328,24 @@ ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL };  </b>/**< this con
  
 </p></pre><BR>
 
+<pre><b>typedef struct POOL_ctx_s ZSTD_threadPool;
+ZSTDLIB_STATIC_API ZSTD_threadPool* ZSTD_createThreadPool(size_t numThreads);
+ZSTDLIB_STATIC_API void ZSTD_freeThreadPool (ZSTD_threadPool* pool);  </b>/* accept NULL pointer */<b>
+ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refThreadPool(ZSTD_CCtx* cctx, ZSTD_threadPool* pool);
+</b><p>  These prototypes make it possible to share a thread pool among multiple compression contexts.
+  This can limit resources for applications with multiple threads where each one uses
+  a threaded compression mode (via ZSTD_c_nbWorkers parameter).
+  ZSTD_createThreadPool creates a new thread pool with a given number of threads.
+  Note that the lifetime of such pool must exist while being used.
+  ZSTD_CCtx_refThreadPool assigns a thread pool to a context (use NULL argument value
+  to use an internal thread pool).
+  ZSTD_freeThreadPool frees a thread pool, accepts NULL pointer.
+ 
+</p></pre><BR>
+
 <a name="Chapter17"></a><h2>Advanced compression functions</h2><pre></pre>
 
-<pre><b>ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);
+<pre><b>ZSTDLIB_STATIC_API ZSTD_CDict* ZSTD_createCDict_byReference(const void* dictBuffer, size_t dictSize, int compressionLevel);
 </b><p>  Create a digested dictionary for compression
   Dictionary content is just referenced, not duplicated.
   As a consequence, `dictBuffer` **must** outlive CDict,
@@ -1313,22 +1353,22 @@ ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL };  </b>/**< this con
   note: equivalent to ZSTD_createCDict_advanced(), with dictLoadMethod==ZSTD_dlm_byRef 
 </p></pre><BR>
 
-<pre><b>ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);
 </b><p> @return ZSTD_compressionParameters structure for a selected compression level and estimated srcSize.
  `estimatedSrcSize` value is optional, select 0 if not known 
 </p></pre><BR>
 
-<pre><b>ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API ZSTD_parameters ZSTD_getParams(int compressionLevel, unsigned long long estimatedSrcSize, size_t dictSize);
 </b><p>  same as ZSTD_getCParams(), but @return a full `ZSTD_parameters` object instead of sub-component `ZSTD_compressionParameters`.
   All fields of `ZSTD_frameParameters` are set to default : contentSize=1, checksum=0, noDictID=0 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_checkCParams(ZSTD_compressionParameters params);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_checkCParams(ZSTD_compressionParameters params);
 </b><p>  Ensure param values remain within authorized range.
  @return 0 on success, or an error code (can be checked with ZSTD_isError()) 
 </p></pre><BR>
 
-<pre><b>ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API ZSTD_compressionParameters ZSTD_adjustCParams(ZSTD_compressionParameters cPar, unsigned long long srcSize, size_t dictSize);
 </b><p>  optimize params for a given `srcSize` and `dictSize`.
  `srcSize` can be unknown, in which case use ZSTD_CONTENTSIZE_UNKNOWN.
  `dictSize` must be `0` when there is no dictionary.
@@ -1358,31 +1398,31 @@ size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
   This prototype will generate compilation warnings. 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtx_loadDictionary_byReference(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtx_loadDictionary_byReference(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
 </b><p>  Same as ZSTD_CCtx_loadDictionary(), but dictionary content is referenced, instead of being copied into CCtx.
   It saves some memory, but also requires that `dict` outlives its usage within `cctx` 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtx_loadDictionary_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtx_loadDictionary_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);
 </b><p>  Same as ZSTD_CCtx_loadDictionary(), but gives finer control over
   how to load the dictionary (by copy ? by reference ?)
   and how to interpret it (automatic ? force raw mode ? full mode only ?) 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtx_refPrefix_advanced(ZSTD_CCtx* cctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType);
 </b><p>  Same as ZSTD_CCtx_refPrefix(), but gives finer control over
   how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtx_getParameter(const ZSTD_CCtx* cctx, ZSTD_cParameter param, int* value);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtx_getParameter(const ZSTD_CCtx* cctx, ZSTD_cParameter param, int* value);
 </b><p>  Get the requested compression parameter value, selected by enum ZSTD_cParameter,
   and store it into int* value.
  @return : 0, or an error code (which can be tested with ZSTD_isError()).
  
 </p></pre><BR>
 
-<pre><b>ZSTD_CCtx_params* ZSTD_createCCtxParams(void);
-size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointer */<b>
+<pre><b>ZSTDLIB_STATIC_API ZSTD_CCtx_params* ZSTD_createCCtxParams(void);
+ZSTDLIB_STATIC_API size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointer */<b>
 </b><p>  Quick howto :
   - ZSTD_createCCtxParams() : Create a ZSTD_CCtx_params structure
   - ZSTD_CCtxParams_setParameter() : Push parameters one by one into
@@ -1401,24 +1441,24 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtxParams_reset(ZSTD_CCtx_params* params);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_reset(ZSTD_CCtx_params* params);
 </b><p>  Reset params to default values.
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtxParams_init(ZSTD_CCtx_params* cctxParams, int compressionLevel);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_init(ZSTD_CCtx_params* cctxParams, int compressionLevel);
 </b><p>  Initializes the compression parameters of cctxParams according to
   compression level. All other parameters are reset to their default values.
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtxParams_init_advanced(ZSTD_CCtx_params* cctxParams, ZSTD_parameters params);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_init_advanced(ZSTD_CCtx_params* cctxParams, ZSTD_parameters params);
 </b><p>  Initializes the compression and frame parameters of cctxParams according to
   params. All other parameters are reset to their default values.
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, int value);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_setParameter(ZSTD_CCtx_params* params, ZSTD_cParameter param, int value);
 </b><p>  Similar to ZSTD_CCtx_setParameter.
   Set one compression parameter, selected by enum ZSTD_cParameter.
   Parameters must be applied to a ZSTD_CCtx using
@@ -1428,14 +1468,14 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtxParams_getParameter(const ZSTD_CCtx_params* params, ZSTD_cParameter param, int* value);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtxParams_getParameter(const ZSTD_CCtx_params* params, ZSTD_cParameter param, int* value);
 </b><p> Similar to ZSTD_CCtx_getParameter.
  Get the requested value of one compression parameter, selected by enum ZSTD_cParameter.
  @result : 0, or an error code (which can be tested with ZSTD_isError()).
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_CCtx_setParametersUsingCCtxParams(
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_CCtx_setParametersUsingCCtxParams(
         ZSTD_CCtx* cctx, const ZSTD_CCtx_params* params);
 </b><p>  Apply a set of ZSTD_CCtx_params to the compression context.
   This can be done even after compression is started,
@@ -1445,7 +1485,7 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_compressStream2_simpleArgs (
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_compressStream2_simpleArgs (
                 ZSTD_CCtx* cctx,
                 void* dst, size_t dstCapacity, size_t* dstPos,
           const void* src, size_t srcSize, size_t* srcPos,
@@ -1459,40 +1499,40 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
 
 <a name="Chapter18"></a><h2>Advanced decompression functions</h2><pre></pre>
 
-<pre><b>unsigned ZSTD_isFrame(const void* buffer, size_t size);
+<pre><b>ZSTDLIB_STATIC_API unsigned ZSTD_isFrame(const void* buffer, size_t size);
 </b><p>  Tells if the content of `buffer` starts with a valid Frame Identifier.
   Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0.
   Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled.
   Note 3 : Skippable Frame Identifiers are considered valid. 
 </p></pre><BR>
 
-<pre><b>ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API ZSTD_DDict* ZSTD_createDDict_byReference(const void* dictBuffer, size_t dictSize);
 </b><p>  Create a digested dictionary, ready to start decompression operation without startup delay.
   Dictionary content is referenced, and therefore stays in dictBuffer.
   It is important that dictBuffer outlives DDict,
   it must remain read accessible throughout the lifetime of DDict 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_DCtx_loadDictionary_byReference(ZSTD_DCtx* dctx, const void* dict, size_t dictSize);
 </b><p>  Same as ZSTD_DCtx_loadDictionary(),
   but references `dict` content instead of copying it into `dctx`.
   This saves memory if `dict` remains around.,
   However, it's imperative that `dict` remains accessible (and unmodified) while being used, so it must outlive decompression. 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_DCtx_loadDictionary_advanced(ZSTD_DCtx* dctx, const void* dict, size_t dictSize, ZSTD_dictLoadMethod_e dictLoadMethod, ZSTD_dictContentType_e dictContentType);
 </b><p>  Same as ZSTD_DCtx_loadDictionary(),
   but gives direct control over
   how to load the dictionary (by copy ? by reference ?)
   and how to interpret it (automatic ? force raw mode ? full mode only ?). 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_DCtx_refPrefix_advanced(ZSTD_DCtx* dctx, const void* prefix, size_t prefixSize, ZSTD_dictContentType_e dictContentType);
 </b><p>  Same as ZSTD_DCtx_refPrefix(), but gives finer control over
   how to interpret prefix content (automatic ? force raw mode (default) ? full mode only ?) 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_DCtx_setMaxWindowSize(ZSTD_DCtx* dctx, size_t maxWindowSize);
 </b><p>  Refuses allocating internal buffers for frames requiring a window size larger than provided limit.
   This protects a decoder context from reserving too much memory for itself (potential attack scenario).
   This parameter is only useful in streaming mode, since no internal buffer is allocated in single-pass mode.
@@ -1501,7 +1541,7 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_DCtx_getParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int* value);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_DCtx_getParameter(ZSTD_DCtx* dctx, ZSTD_dParameter param, int* value);
 </b><p>  Get the requested decompression parameter value, selected by enum ZSTD_dParameter,
   and store it into int* value.
  @return : 0, or an error code (which can be tested with ZSTD_isError()).
@@ -1517,7 +1557,7 @@ size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);
  @return : 0, or an error code (which can be tested using ZSTD_isError()). 
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_decompressStream_simpleArgs (
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_decompressStream_simpleArgs (
                 ZSTD_DCtx* dctx,
                 void* dst, size_t dstCapacity, size_t* dstPos,
           const void* src, size_t srcSize, size_t* srcPos);
@@ -1594,7 +1634,7 @@ size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);
 </b><p> This function is DEPRECATED, and equivalent to:
      ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
      ZSTD_CCtx_refCDict(zcs, cdict);
- 
+
  note : cdict will just be referenced, and must outlive compression session
  This prototype will generate compilation warnings.
  
@@ -1651,7 +1691,7 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
     unsigned nbActiveWorkers;      </b>/* MT only : nb of workers actively compressing at probe time */<b>
 } ZSTD_frameProgression;
 </b></pre><BR>
-<pre><b>size_t ZSTD_toFlushNow(ZSTD_CCtx* cctx);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_toFlushNow(ZSTD_CCtx* cctx);
 </b><p>  Tell how many bytes are ready to be flushed immediately.
   Useful for multithreading scenarios (nbWorkers >= 1).
   Probe the oldest active job, defined as oldest job not yet entirely flushed,
@@ -1667,7 +1707,7 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
 </p></pre><BR>
 
 <h3>Advanced Streaming decompression functions</h3><pre></pre><b><pre></pre></b><BR>
-<pre><b>size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_initDStream_usingDict(ZSTD_DStream* zds, const void* dict, size_t dictSize);
 </b><p>
      ZSTD_DCtx_reset(zds, ZSTD_reset_session_only);
      ZSTD_DCtx_loadDictionary(zds, dict, dictSize);
@@ -1677,7 +1717,7 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_initDStream_usingDDict(ZSTD_DStream* zds, const ZSTD_DDict* ddict);
 </b><p>
      ZSTD_DCtx_reset(zds, ZSTD_reset_session_only);
      ZSTD_DCtx_refDDict(zds, ddict);
@@ -1687,7 +1727,7 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
  
 </p></pre><BR>
 
-<pre><b>size_t ZSTD_resetDStream(ZSTD_DStream* zds);
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_resetDStream(ZSTD_DStream* zds);
 </b><p>
      ZSTD_DCtx_reset(zds, ZSTD_reset_session_only);
 
@@ -1731,10 +1771,10 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
   `ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress again.
 <BR></pre>
 
-<h3>Buffer-less streaming compression functions</h3><pre></pre><b><pre>size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
-size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
-size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); </b>/**< note: fails if cdict==NULL */<b>
-size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); </b>/**<  note: if pledgedSrcSize is not known, use ZSTD_CONTENTSIZE_UNKNOWN */<b>
+<h3>Buffer-less streaming compression functions</h3><pre></pre><b><pre>ZSTDLIB_STATIC_API size_t ZSTD_compressBegin(ZSTD_CCtx* cctx, int compressionLevel);
+ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, int compressionLevel);
+ZSTDLIB_STATIC_API size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); </b>/**< note: fails if cdict==NULL */<b>
+ZSTDLIB_STATIC_API size_t ZSTD_copyCCtx(ZSTD_CCtx* cctx, const ZSTD_CCtx* preparedCCtx, unsigned long long pledgedSrcSize); </b>/**<  note: if pledgedSrcSize is not known, use ZSTD_CONTENTSIZE_UNKNOWN */<b>
 </pre></b><BR>
 <pre><b>size_t ZSTD_compressBegin_advanced(ZSTD_CCtx* cctx, const void* dict, size_t dictSize, ZSTD_parameters params, unsigned long long pledgedSrcSize); </b>/**< pledgedSrcSize : If srcSize is not known at init time, use ZSTD_CONTENTSIZE_UNKNOWN */<b>
 </b></pre><BR>
@@ -1820,12 +1860,12 @@ typedef struct {
     unsigned checksumFlag;
 } ZSTD_frameHeader;
 </pre></b><BR>
-<pre><b>size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   </b>/**< doesn't consume input */<b>
+<pre><b>ZSTDLIB_STATIC_API size_t ZSTD_getFrameHeader(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize);   </b>/**< doesn't consume input */<b>
 </b>/*! ZSTD_getFrameHeader_advanced() :<b>
  *  same as ZSTD_getFrameHeader(),
  *  with added capability to select a format (like ZSTD_f_zstd1_magicless) */
-size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format);
-size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize);  </b>/**< when frame content size is not known, pass in frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN */<b>
+ZSTDLIB_STATIC_API size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, size_t srcSize, ZSTD_format_e format);
+ZSTDLIB_STATIC_API size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long long frameContentSize);  </b>/**< when frame content size is not known, pass in frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN */<b>
 </b><p>  decode Frame Header, or requires larger `srcSize`.
  @return : 0, `zfhPtr` is correctly filled,
           >0, `srcSize` is too small, value is wanted `srcSize` amount,
@@ -1861,10 +1901,10 @@ size_t ZSTD_decodingBufferSize_min(unsigned long long windowSize, unsigned long
         Use ZSTD_insertBlock() for such a case.
 </p></pre><BR>
 
-<h3>Raw zstd block functions</h3><pre></pre><b><pre>size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
-size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
-size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
-size_t ZSTD_insertBlock    (ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  </b>/**< insert uncompressed block into `dctx` history. Useful for multi-blocks decompression. */<b>
+<h3>Raw zstd block functions</h3><pre></pre><b><pre>ZSTDLIB_STATIC_API size_t ZSTD_getBlockSize   (const ZSTD_CCtx* cctx);
+ZSTDLIB_STATIC_API size_t ZSTD_compressBlock  (ZSTD_CCtx* cctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
+ZSTDLIB_STATIC_API size_t ZSTD_decompressBlock(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize);
+ZSTDLIB_STATIC_API size_t ZSTD_insertBlock    (ZSTD_DCtx* dctx, const void* blockStart, size_t blockSize);  </b>/**< insert uncompressed block into `dctx` history. Useful for multi-blocks decompression. */<b>
 </pre></b><BR>
 </html>
 </body>

examples/common.h

@@ -57,7 +57,7 @@ typedef enum {
  * Check the zstd error code and die if an error occurred after printing a
  * message.
  */
-#define CHECK_ZSTD(fn, ...)                                      \
+#define CHECK_ZSTD(fn)                                           \
     do {                                                         \
         size_t const err = (fn);                                 \
         CHECK(!ZSTD_isError(err), "%s", ZSTD_getErrorName(err)); \

examples/streaming_compression.c

@@ -15,9 +15,12 @@
 #include <zstd.h>      // presumes zstd library is installed
 #include "common.h"    // Helper functions, CHECK(), and CHECK_ZSTD()
 
-
-static void compressFile_orDie(const char* fname, const char* outName, int cLevel)
+static void compressFile_orDie(const char* fname, const char* outName, int cLevel,
+                               int nbThreads)
 {
+    fprintf (stderr, "Starting compression of %s with level %d, using %d threads\n",
+             fname, cLevel, nbThreads);
+
     /* Open the input and output files. */
     FILE* const fin  = fopen_orDie(fname, "rb");
     FILE* const fout = fopen_orDie(outName, "wb");
@@ -39,7 +42,7 @@ static void compressFile_orDie(const char* fname, const char* outName, int cLeve
      */
     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, cLevel) );
     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_checksumFlag, 1) );
-    ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, 4);
+    ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, nbThreads);
 
     /* This loop read from the input file, compresses that entire chunk,
      * and writes all output produced to the output file.
@@ -106,19 +109,32 @@ int main(int argc, const char** argv)
 {
     const char* const exeName = argv[0];
 
-    if (argc!=2) {
+    if (argc < 2) {
         printf("wrong arguments\n");
         printf("usage:\n");
-        printf("%s FILE\n", exeName);
+        printf("%s FILE [LEVEL] [THREADS]\n", exeName);
         return 1;
     }
 
+    int cLevel = 1;
+    int nbThreads = 4;
+
+    if (argc >= 3) {
+      cLevel = atoi (argv[2]);
+      CHECK(cLevel != 0, "can't parse LEVEL!");
+    }
+
+    if (argc >= 4) {
+      nbThreads = atoi (argv[3]);
+      CHECK(nbThreads != 0, "can't parse THREADS!");
+    }
+
     const char* const inFilename = argv[1];
 
     char* const outFilename = createOutFilename_orDie(inFilename);
-    compressFile_orDie(inFilename, outFilename, 1);
+    compressFile_orDie(inFilename, outFilename, cLevel, nbThreads);
 
     free(outFilename);   /* not strictly required, since program execution stops there,
-                          * but some static analyzer main complain otherwise */
+                          * but some static analyzer may complain otherwise */
     return 0;
 }

examples/streaming_compression_thread_pool.c

@@ -28,8 +28,10 @@ typedef struct compress_args
 
 static void *compressFile_orDie(void *data)
 {
+    const int nbThreads = 16;
+
     compress_args_t *args = (compress_args_t *)data;
-    fprintf (stderr, "Starting compression of %s with level %d\n", args->fname, args->cLevel);
+    fprintf (stderr, "Starting compression of %s with level %d, using %d threads\n", args->fname, args->cLevel, nbThreads);
     /* Open the input and output files. */
     FILE* const fin  = fopen_orDie(args->fname, "rb");
     FILE* const fout = fopen_orDie(args->outName, "wb");
@@ -56,9 +58,9 @@ static void *compressFile_orDie(void *data)
      */
     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_compressionLevel, args->cLevel) );
     CHECK_ZSTD( ZSTD_CCtx_setParameter(cctx, ZSTD_c_checksumFlag, 1) );
-    ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, 16);
+    ZSTD_CCtx_setParameter(cctx, ZSTD_c_nbWorkers, nbThreads);
 
-    /* This loop read from the input file, compresses that entire chunk,
+    /* This loop reads from the input file, compresses that entire chunk,
      * and writes all output produced to the output file.
      */
     size_t const toRead = buffInSize;

lib/Makefile

@@ -8,110 +8,13 @@
 # You may select, at your option, one of the above-listed licenses.
 # ################################################################
 
-# Note: by default, the static library is built single-threaded and dynamic library is built
-# multi-threaded. It is possible to force multi or single threaded builds by appending
-# -mt or -nomt to the build target (like lib-mt for multi-threaded, lib-nomt for single-threaded).
-.PHONY: default
-default: lib-release
-
-# define silent mode as default (verbose mode with V=1 or VERBOSE=1)
-$(V)$(VERBOSE).SILENT:
-
-# When cross-compiling from linux to windows,
-# one might need to specify TARGET_SYSTEM as "Windows."
-# Building from Fedora fails without it.
-# (but Ubuntu and Debian don't need to set anything)
-TARGET_SYSTEM ?= $(OS)
-
-# Version numbers
-LIBVER_MAJOR_SCRIPT:=`sed -n '/define ZSTD_VERSION_MAJOR/s/.*[[:blank:]]\([0-9][0-9]*\).*/\1/p' < ./zstd.h`
-LIBVER_MINOR_SCRIPT:=`sed -n '/define ZSTD_VERSION_MINOR/s/.*[[:blank:]]\([0-9][0-9]*\).*/\1/p' < ./zstd.h`
-LIBVER_PATCH_SCRIPT:=`sed -n '/define ZSTD_VERSION_RELEASE/s/.*[[:blank:]]\([0-9][0-9]*\).*/\1/p' < ./zstd.h`
-LIBVER_SCRIPT:= $(LIBVER_MAJOR_SCRIPT).$(LIBVER_MINOR_SCRIPT).$(LIBVER_PATCH_SCRIPT)
-LIBVER_MAJOR := $(shell echo $(LIBVER_MAJOR_SCRIPT))
-LIBVER_MINOR := $(shell echo $(LIBVER_MINOR_SCRIPT))
-LIBVER_PATCH := $(shell echo $(LIBVER_PATCH_SCRIPT))
-LIBVER := $(shell echo $(LIBVER_SCRIPT))
-VERSION?= $(LIBVER)
-CCVER := $(shell $(CC) --version)
-
-# ZSTD_LIB_MINIFY is a helper variable that
-# configures a bunch of other variables to space-optimized defaults.
-ZSTD_LIB_MINIFY ?= 0
-ifneq ($(ZSTD_LIB_MINIFY), 0)
-  HAVE_CC_OZ ?= $(shell echo "" | $(CC) -Oz -x c -c - -o /dev/null 2> /dev/null && echo 1 || echo 0)
-  ZSTD_LEGACY_SUPPORT ?= 0
-  ZSTD_LIB_DEPRECATED ?= 0
-  HUF_FORCE_DECOMPRESS_X1 ?= 1
-  ZSTD_FORCE_DECOMPRESS_SHORT ?= 1
-  ZSTD_NO_INLINE ?= 1
-  ZSTD_STRIP_ERROR_STRINGS ?= 1
-ifneq ($(HAVE_CC_OZ), 0)
-    # Some compilers (clang) support an even more space-optimized setting.
-    CFLAGS += -Oz
-else
-    CFLAGS += -Os
-endif
-  CFLAGS += -fno-stack-protector -fomit-frame-pointer -fno-ident \
-            -DDYNAMIC_BMI2=0 -DNDEBUG
-else
-  CFLAGS += -O3
-endif
-
-DEBUGLEVEL ?= 0
-CPPFLAGS += -DXXH_NAMESPACE=ZSTD_ -DDEBUGLEVEL=$(DEBUGLEVEL)
-ifeq ($(TARGET_SYSTEM),Windows_NT)   # MinGW assumed
-  CPPFLAGS += -D__USE_MINGW_ANSI_STDIO   # compatibility with %zu formatting
-endif
-DEBUGFLAGS= -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
-            -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
-            -Wstrict-prototypes -Wundef -Wpointer-arith \
-            -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings \
-            -Wredundant-decls -Wmissing-prototypes -Wc++-compat
-CFLAGS   += $(DEBUGFLAGS) $(MOREFLAGS)
-FLAGS     = $(CPPFLAGS) $(CFLAGS)
-
-CPPFLAGS_DYNLIB  = -DZSTD_MULTITHREAD # dynamic library build defaults to multi-threaded
-LDFLAGS_DYNLIB   = -pthread
-CPPFLAGS_STATLIB =                    # static library build defaults to single-threaded
-
-HAVE_COLORNEVER = $(shell echo a | grep --color=never a > /dev/null 2> /dev/null && echo 1 || echo 0)
-GREP_OPTIONS ?=
-ifeq ($HAVE_COLORNEVER, 1)
-  GREP_OPTIONS += --color=never
-endif
-GREP = grep $(GREP_OPTIONS)
-SED_ERE_OPT ?= -E
-
-ZSTDCOMMON_FILES := $(sort $(wildcard common/*.c))
-ZSTDCOMP_FILES := $(sort $(wildcard compress/*.c))
-ZSTDDECOMP_FILES := $(sort $(wildcard decompress/*.c))
-ZDICT_FILES := $(sort $(wildcard dictBuilder/*.c))
-ZDEPR_FILES := $(sort $(wildcard deprecated/*.c))
-ZSTD_FILES := $(ZSTDCOMMON_FILES)
-
-ifeq ($(findstring GCC,$(CCVER)),GCC)
-decompress/zstd_decompress_block.o : CFLAGS+=-fno-tree-vectorize
-endif
-
 # Modules
 ZSTD_LIB_COMPRESSION ?= 1
 ZSTD_LIB_DECOMPRESSION ?= 1
 ZSTD_LIB_DICTBUILDER ?= 1
 ZSTD_LIB_DEPRECATED ?= 0
 
-# Legacy support
-ZSTD_LEGACY_SUPPORT ?= 5
-ZSTD_LEGACY_MULTITHREADED_API ?= 0
-
-# Build size optimizations
-HUF_FORCE_DECOMPRESS_X1 ?= 0
-HUF_FORCE_DECOMPRESS_X2 ?= 0
-ZSTD_FORCE_DECOMPRESS_SHORT ?= 0
-ZSTD_FORCE_DECOMPRESS_LONG ?= 0
-ZSTD_NO_INLINE ?= 0
-ZSTD_STRIP_ERROR_STRINGS ?= 0
-
+# Input variables for libzstd.mk
 ifeq ($(ZSTD_LIB_COMPRESSION), 0)
   ZSTD_LIB_DICTBUILDER = 0
   ZSTD_LIB_DEPRECATED = 0
@@ -122,86 +25,46 @@ ifeq ($(ZSTD_LIB_DECOMPRESSION), 0)
   ZSTD_LIB_DEPRECATED = 0
 endif
 
+include libzstd.mk
+
+ZSTD_FILES := $(ZSTD_COMMON_FILES) $(ZSTD_LEGACY_FILES)
+
 ifneq ($(ZSTD_LIB_COMPRESSION), 0)
-  ZSTD_FILES += $(ZSTDCOMP_FILES)
+  ZSTD_FILES += $(ZSTD_COMPRESS_FILES)
 endif
 
 ifneq ($(ZSTD_LIB_DECOMPRESSION), 0)
-  ZSTD_FILES += $(ZSTDDECOMP_FILES)
+  ZSTD_FILES += $(ZSTD_DECOMPRESS_FILES)
 endif
 
 ifneq ($(ZSTD_LIB_DEPRECATED), 0)
-  ZSTD_FILES += $(ZDEPR_FILES)
+  ZSTD_FILES += $(ZSTD_DEPRECATED_FILES)
 endif
 
 ifneq ($(ZSTD_LIB_DICTBUILDER), 0)
-  ZSTD_FILES += $(ZDICT_FILES)
+  ZSTD_FILES += $(ZSTD_DICTBUILDER_FILES)
 endif
 
-ifneq ($(HUF_FORCE_DECOMPRESS_X1), 0)
-  CFLAGS += -DHUF_FORCE_DECOMPRESS_X1
-endif
-
-ifneq ($(HUF_FORCE_DECOMPRESS_X2), 0)
-  CFLAGS += -DHUF_FORCE_DECOMPRESS_X2
-endif
-
-ifneq ($(ZSTD_FORCE_DECOMPRESS_SHORT), 0)
-  CFLAGS += -DZSTD_FORCE_DECOMPRESS_SHORT
-endif
-
-ifneq ($(ZSTD_FORCE_DECOMPRESS_LONG), 0)
-  CFLAGS += -DZSTD_FORCE_DECOMPRESS_LONG
-endif
-
-ifneq ($(ZSTD_NO_INLINE), 0)
-  CFLAGS += -DZSTD_NO_INLINE
-endif
-
-ifneq ($(ZSTD_STRIP_ERROR_STRINGS), 0)
-  CFLAGS += -DZSTD_STRIP_ERROR_STRINGS
-endif
-
-ifneq ($(ZSTD_LEGACY_MULTITHREADED_API), 0)
-  CFLAGS += -DZSTD_LEGACY_MULTITHREADED_API
-endif
-
-ifneq ($(ZSTD_LEGACY_SUPPORT), 0)
-ifeq ($(shell test $(ZSTD_LEGACY_SUPPORT) -lt 8; echo $$?), 0)
-  ZSTD_FILES += $(shell ls legacy/*.c | $(GREP) 'v0[$(ZSTD_LEGACY_SUPPORT)-7]')
-endif
-endif
-CPPFLAGS  += -DZSTD_LEGACY_SUPPORT=$(ZSTD_LEGACY_SUPPORT)
-
 ZSTD_LOCAL_SRC := $(notdir $(ZSTD_FILES))
-ZSTD_LOCAL_OBJ := $(ZSTD_LOCAL_SRC:.c=.o)
+ZSTD_LOCAL_OBJ0 := $(ZSTD_LOCAL_SRC:.c=.o)
+ZSTD_LOCAL_OBJ := $(ZSTD_LOCAL_OBJ0:.S=.o)
 
-ZSTD_SUBDIR := common compress decompress dictBuilder legacy deprecated
-vpath %.c $(ZSTD_SUBDIR)
+VERSION := $(ZSTD_VERSION)
 
-UNAME := $(shell uname)
+# Note: by default, the static library is built single-threaded and dynamic library is built
+# multi-threaded. It is possible to force multi or single threaded builds by appending
+# -mt or -nomt to the build target (like lib-mt for multi-threaded, lib-nomt for single-threaded).
+.PHONY: default
+default: lib-release
 
-ifndef BUILD_DIR
-ifeq ($(UNAME), Darwin)
-  ifeq ($(shell md5 < /dev/null > /dev/null; echo $$?), 0)
-    HASH ?= md5
-  endif
-else ifeq ($(UNAME), FreeBSD)
-  HASH ?= gmd5sum
-else ifeq ($(UNAME), NetBSD)
-  HASH ?= md5 -n
-else ifeq ($(UNAME), OpenBSD)
-  HASH ?= md5
+CPPFLAGS_DYNLIB  += -DZSTD_MULTITHREAD # dynamic library build defaults to multi-threaded
+LDFLAGS_DYNLIB   += -pthread
+CPPFLAGS_STATLIB +=                    # static library build defaults to single-threaded
+
+
+ifeq ($(findstring GCC,$(CCVER)),GCC)
+decompress/zstd_decompress_block.o : CFLAGS+=-fno-tree-vectorize
 endif
-HASH ?= md5sum
-
-HASH_DIR = conf_$(shell echo $(CC) $(CPPFLAGS) $(CFLAGS) $(LDFLAGS) $(ZSTD_FILES) | $(HASH) | cut -f 1 -d " " )
-HAVE_HASH :=$(shell echo 1 | $(HASH) > /dev/null && echo 1 || echo 0)
-ifeq ($(HAVE_HASH),0)
-  $(info warning : could not find HASH ($(HASH)), needed to differentiate builds using different flags)
-  BUILD_DIR := obj/generic_noconf
-endif
-endif # BUILD_DIR
 
 
 # macOS linker doesn't support -soname, and use different extension
@@ -212,19 +75,16 @@ ifeq ($(UNAME), Darwin)
   SHARED_EXT_VER = $(LIBVER).$(SHARED_EXT)
   SONAME_FLAGS = -install_name $(LIBDIR)/libzstd.$(SHARED_EXT_MAJOR) -compatibility_version $(LIBVER_MAJOR) -current_version $(LIBVER)
 else
-  SONAME_FLAGS = -Wl,-soname=libzstd.$(SHARED_EXT).$(LIBVER_MAJOR)
+  ifeq ($(UNAME), AIX)
+    SONAME_FLAGS =
+  else
+    SONAME_FLAGS = -Wl,-soname=libzstd.$(SHARED_EXT).$(LIBVER_MAJOR)
+  endif
   SHARED_EXT = so
   SHARED_EXT_MAJOR = $(SHARED_EXT).$(LIBVER_MAJOR)
   SHARED_EXT_VER = $(SHARED_EXT).$(LIBVER)
 endif
 
-SET_CACHE_DIRECTORY = \
-   +$(MAKE) --no-print-directory $@ \
-    BUILD_DIR=obj/$(HASH_DIR) \
-    CPPFLAGS="$(CPPFLAGS)" \
-    CFLAGS="$(CFLAGS)" \
-    LDFLAGS="$(LDFLAGS)"
-
 
 .PHONY: all
 all: lib
@@ -233,6 +93,13 @@ all: lib
 .PHONY: libzstd.a  # must be run every time
 libzstd.a: CPPFLAGS += $(CPPFLAGS_STATLIB)
 
+SET_CACHE_DIRECTORY = \
+   +$(MAKE) --no-print-directory $@ \
+    BUILD_DIR=obj/$(HASH_DIR) \
+    CPPFLAGS="$(CPPFLAGS)" \
+    CFLAGS="$(CFLAGS)" \
+    LDFLAGS="$(LDFLAGS)"
+
 ifndef BUILD_DIR
 # determine BUILD_DIR from compilation flags
 
@@ -343,6 +210,14 @@ $(ZSTD_STATLIB_DIR)/%.o : %.c $(ZSTD_STATLIB_DIR)/%.d | $(ZSTD_STATLIB_DIR)
 	@echo CC $@
 	$(COMPILE.c) $(DEPFLAGS) $(ZSTD_STATLIB_DIR)/$*.d $(OUTPUT_OPTION) $<
 
+$(ZSTD_DYNLIB_DIR)/%.o : %.S | $(ZSTD_DYNLIB_DIR)
+	@echo AS $@
+	$(COMPILE.S) $(OUTPUT_OPTION) $<
+
+$(ZSTD_STATLIB_DIR)/%.o : %.S | $(ZSTD_STATLIB_DIR)
+	@echo AS $@
+	$(COMPILE.S) $(OUTPUT_OPTION) $<
+
 MKDIR ?= mkdir
 $(BUILD_DIR) $(ZSTD_DYNLIB_DIR) $(ZSTD_STATLIB_DIR):
 	$(MKDIR) -p $@
@@ -374,9 +249,9 @@ clean:
 #-----------------------------------------------------------------------------
 # make install is validated only for below listed environments
 #-----------------------------------------------------------------------------
-ifneq (,$(filter $(UNAME),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD NetBSD DragonFly SunOS Haiku))
+ifneq (,$(filter $(UNAME),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD NetBSD DragonFly SunOS Haiku AIX))
 
-all: libzstd.pc
+lib: libzstd.pc
 
 HAS_EXPLICIT_EXEC_PREFIX := $(if $(or $(EXEC_PREFIX),$(exec_prefix)),1,)
 
@@ -421,16 +296,16 @@ INSTALL_PROGRAM ?= $(INSTALL)
 INSTALL_DATA    ?= $(INSTALL) -m 644
 
 
-libzstd.pc:
 libzstd.pc: libzstd.pc.in
 	@echo creating pkgconfig
 	@sed $(SED_ERE_OPT) \
 	        -e 's|@PREFIX@|$(PREFIX)|' \
 	        -e 's|@EXEC_PREFIX@|$(PCEXEC_PREFIX)|' \
-          -e 's|@INCLUDEDIR@|$(PCINCPREFIX)$(PCINCDIR)|' \
-          -e 's|@LIBDIR@|$(PCLIBPREFIX)$(PCLIBDIR)|' \
-          -e 's|@VERSION@|$(VERSION)|' \
-          $< >$@
+	        -e 's|@INCLUDEDIR@|$(PCINCPREFIX)$(PCINCDIR)|' \
+	        -e 's|@LIBDIR@|$(PCLIBPREFIX)$(PCLIBDIR)|' \
+	        -e 's|@VERSION@|$(VERSION)|' \
+	        -e 's|@LIBS_PRIVATE@|$(LDFLAGS_DYNLIB)|' \
+	        $< >$@
 
 .PHONY: install
 install: install-pc install-static install-shared install-includes

lib/README.md

@@ -125,7 +125,7 @@ The file structure is designed to make this selection manually achievable for an
   `ZSTD_getErrorName` (implied by `ZSTD_LIB_MINIFY`).
 
   Finally, when integrating into your application, make sure you're doing link-
-  time optimation and unused symbol garbage collection (via some combination of,
+  time optimization and unused symbol garbage collection (via some combination of,
   e.g., `-flto`, `-ffat-lto-objects`, `-fuse-linker-plugin`,
   `-ffunction-sections`, `-fdata-sections`, `-fmerge-all-constants`,
   `-Wl,--gc-sections`, `-Wl,-z,norelro`, and an archiver that understands
@@ -155,6 +155,12 @@ The file structure is designed to make this selection manually achievable for an
 - The build macro `ZSTD_NO_INTRINSICS` can be defined to disable all explicit intrinsics.
   Compiler builtins are still used.
 
+- The build macro `ZSTD_DECODER_INTERNAL_BUFFER` can be set to control
+  the amount of extra memory used during decompression to store literals.
+  This defaults to 64kB.  Reducing this value reduces the memory footprint of
+  `ZSTD_DCtx` decompression contexts,
+  but might also result in a small decompression speed cost.
+
 
 #### Windows : using MinGW+MSYS to create DLL
 

lib/common/bitstream.h

@@ -143,10 +143,16 @@ MEM_STATIC unsigned BIT_highbit32 (U32 val)
     {
 #   if defined(_MSC_VER)   /* Visual */
 #       if STATIC_BMI2 == 1
-		return _lzcnt_u32(val) ^ 31;
+            return _lzcnt_u32(val) ^ 31;
 #       else
-		unsigned long r = 0;
-		return _BitScanReverse(&r, val) ? (unsigned)r : 0;
+            if (val != 0) {
+                unsigned long r;
+                _BitScanReverse(&r, val);
+                return (unsigned)r;
+            } else {
+                /* Should not reach this code path */
+                __assume(0);
+            }
 #       endif
 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */
         return __builtin_clz (val) ^ 31;
@@ -293,22 +299,22 @@ MEM_STATIC size_t BIT_initDStream(BIT_DStream_t* bitD, const void* srcBuffer, si
         switch(srcSize)
         {
         case 7: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[6]) << (sizeof(bitD->bitContainer)*8 - 16);
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         case 6: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[5]) << (sizeof(bitD->bitContainer)*8 - 24);
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         case 5: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[4]) << (sizeof(bitD->bitContainer)*8 - 32);
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         case 4: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[3]) << 24;
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         case 3: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[2]) << 16;
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         case 2: bitD->bitContainer += (size_t)(((const BYTE*)(srcBuffer))[1]) <<  8;
-                /* fall-through */
+                ZSTD_FALLTHROUGH;
 
         default: break;
         }
@@ -332,7 +338,16 @@ MEM_STATIC FORCE_INLINE_ATTR size_t BIT_getMiddleBits(size_t bitContainer, U32 c
     U32 const regMask = sizeof(bitContainer)*8 - 1;
     /* if start > regMask, bitstream is corrupted, and result is undefined */
     assert(nbBits < BIT_MASK_SIZE);
+    /* x86 transform & ((1 << nbBits) - 1) to bzhi instruction, it is better
+     * than accessing memory. When bmi2 instruction is not present, we consider
+     * such cpus old (pre-Haswell, 2013) and their performance is not of that
+     * importance.
+     */
+#if defined(__x86_64__) || defined(_M_X86)
+    return (bitContainer >> (start & regMask)) & ((((U64)1) << nbBits) - 1);
+#else
     return (bitContainer >> (start & regMask)) & BIT_mask[nbBits];
+#endif
 }
 
 MEM_STATIC FORCE_INLINE_ATTR size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits)

lib/common/compiler.h

@@ -11,6 +11,8 @@
 #ifndef ZSTD_COMPILER_H
 #define ZSTD_COMPILER_H
 
+#include "portability_macros.h"
+
 /*-*******************************************************
 *  Compiler specifics
 *********************************************************/
@@ -40,7 +42,7 @@
 
 /**
   On MSVC qsort requires that functions passed into it use the __cdecl calling conversion(CC).
-  This explictly marks such functions as __cdecl so that the code will still compile
+  This explicitly marks such functions as __cdecl so that the code will still compile
   if a CC other than __cdecl has been made the default.
 */
 #if  defined(_MSC_VER)
@@ -92,29 +94,17 @@
 
 
 /* target attribute */
-#ifndef __has_attribute
-  #define __has_attribute(x) 0  /* Compatibility with non-clang compilers. */
-#endif
 #if defined(__GNUC__) || defined(__ICCARM__)
 #  define TARGET_ATTRIBUTE(target) __attribute__((__target__(target)))
 #else
 #  define TARGET_ATTRIBUTE(target)
 #endif
 
-/* Enable runtime BMI2 dispatch based on the CPU.
- * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
+/* Target attribute for BMI2 dynamic dispatch.
+ * Enable lzcnt, bmi, and bmi2.
+ * We test for bmi1 & bmi2. lzcnt is included in bmi1.
  */
-#ifndef DYNAMIC_BMI2
-  #if ((defined(__clang__) && __has_attribute(__target__)) \
-      || (defined(__GNUC__) \
-          && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
-      && (defined(__x86_64__) || defined(_M_X86)) \
-      && !defined(__BMI2__)
-  #  define DYNAMIC_BMI2 1
-  #else
-  #  define DYNAMIC_BMI2 0
-  #endif
-#endif
+#define BMI2_TARGET_ATTRIBUTE TARGET_ATTRIBUTE("lzcnt,bmi,bmi2")
 
 /* prefetch
  * can be disabled, by declaring NO_PREFETCH build macro */
@@ -150,8 +140,9 @@
 }
 
 /* vectorization
- * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax */
-#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__)
+ * older GCC (pre gcc-4.3 picked as the cutoff) uses a different syntax,
+ * and some compilers, like Intel ICC and MCST LCC, do not support it at all. */
+#if !defined(__INTEL_COMPILER) && !defined(__clang__) && defined(__GNUC__) && !defined(__LCC__)
 #  if (__GNUC__ == 4 && __GNUC_MINOR__ > 3) || (__GNUC__ >= 5)
 #    define DONT_VECTORIZE __attribute__((optimize("no-tree-vectorize")))
 #  else
@@ -197,25 +188,91 @@
     #define STATIC_BMI2 0
 #endif
 
-/* compat. with non-clang compilers */
-#ifndef __has_builtin
-#  define __has_builtin(x) 0
-#endif
-
-/* compat. with non-clang compilers */
-#ifndef __has_feature
-#  define __has_feature(x) 0
-#endif
-
-/* detects whether we are being compiled under msan */
-#ifndef ZSTD_MEMORY_SANITIZER
-#  if __has_feature(memory_sanitizer)
-#    define ZSTD_MEMORY_SANITIZER 1
-#  else
-#    define ZSTD_MEMORY_SANITIZER 0
+/* compile time determination of SIMD support */
+#if !defined(ZSTD_NO_INTRINSICS)
+#  if defined(__SSE2__) || defined(_M_AMD64) || (defined (_M_IX86) && defined(_M_IX86_FP) && (_M_IX86_FP >= 2))
+#    define ZSTD_ARCH_X86_SSE2
+#  endif
+#  if defined(__ARM_NEON) || defined(_M_ARM64)
+#    define ZSTD_ARCH_ARM_NEON
+#  endif
+#
+#  if defined(ZSTD_ARCH_X86_SSE2)
+#    include <emmintrin.h>
+#  elif defined(ZSTD_ARCH_ARM_NEON)
+#    include <arm_neon.h>
 #  endif
 #endif
 
+/* C-language Attributes are added in C23. */
+#if defined(__STDC_VERSION__) && (__STDC_VERSION__ > 201710L) && defined(__has_c_attribute)
+# define ZSTD_HAS_C_ATTRIBUTE(x) __has_c_attribute(x)
+#else
+# define ZSTD_HAS_C_ATTRIBUTE(x) 0
+#endif
+
+/* Only use C++ attributes in C++. Some compilers report support for C++
+ * attributes when compiling with C.
+ */
+#if defined(__cplusplus) && defined(__has_cpp_attribute)
+# define ZSTD_HAS_CPP_ATTRIBUTE(x) __has_cpp_attribute(x)
+#else
+# define ZSTD_HAS_CPP_ATTRIBUTE(x) 0
+#endif
+
+/* Define ZSTD_FALLTHROUGH macro for annotating switch case with the 'fallthrough' attribute.
+ * - C23: https://en.cppreference.com/w/c/language/attributes/fallthrough
+ * - CPP17: https://en.cppreference.com/w/cpp/language/attributes/fallthrough
+ * - Else: __attribute__((__fallthrough__))
+ */
+#ifndef ZSTD_FALLTHROUGH
+# if ZSTD_HAS_C_ATTRIBUTE(fallthrough)
+#  define ZSTD_FALLTHROUGH [[fallthrough]]
+# elif ZSTD_HAS_CPP_ATTRIBUTE(fallthrough)
+#  define ZSTD_FALLTHROUGH [[fallthrough]]
+# elif __has_attribute(__fallthrough__)
+/* Leading semicolon is to satisfy gcc-11 with -pedantic. Without the semicolon
+ * gcc complains about: a label can only be part of a statement and a declaration is not a statement.
+ */
+#  define ZSTD_FALLTHROUGH ; __attribute__((__fallthrough__))
+# else
+#  define ZSTD_FALLTHROUGH
+# endif
+#endif
+
+/*-**************************************************************
+*  Alignment check
+*****************************************************************/
+
+/* this test was initially positioned in mem.h,
+ * but this file is removed (or replaced) for linux kernel
+ * so it's now hosted in compiler.h,
+ * which remains valid for both user & kernel spaces.
+ */
+
+#ifndef ZSTD_ALIGNOF
+# if defined(__GNUC__) || defined(_MSC_VER)
+/* covers gcc, clang & MSVC */
+/* note : this section must come first, before C11,
+ * due to a limitation in the kernel source generator */
+#  define ZSTD_ALIGNOF(T) __alignof(T)
+
+# elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
+/* C11 support */
+#  include <stdalign.h>
+#  define ZSTD_ALIGNOF(T) alignof(T)
+
+# else
+/* No known support for alignof() - imperfect backup */
+#  define ZSTD_ALIGNOF(T) (sizeof(void*) < sizeof(T) ? sizeof(void*) : sizeof(T))
+
+# endif
+#endif /* ZSTD_ALIGNOF */
+
+/*-**************************************************************
+*  Sanitizer
+*****************************************************************/
+
 #if ZSTD_MEMORY_SANITIZER
 /* Not all platforms that support msan provide sanitizers/msan_interface.h.
  * We therefore declare the functions we need ourselves, rather than trying to
@@ -237,17 +294,6 @@ void __msan_poison(const volatile void *a, size_t size);
 intptr_t __msan_test_shadow(const volatile void *x, size_t size);
 #endif
 
-/* detects whether we are being compiled under asan */
-#ifndef ZSTD_ADDRESS_SANITIZER
-#  if __has_feature(address_sanitizer)
-#    define ZSTD_ADDRESS_SANITIZER 1
-#  elif defined(__SANITIZE_ADDRESS__)
-#    define ZSTD_ADDRESS_SANITIZER 1
-#  else
-#    define ZSTD_ADDRESS_SANITIZER 0
-#  endif
-#endif
-
 #if ZSTD_ADDRESS_SANITIZER
 /* Not all platforms that support asan provide sanitizers/asan_interface.h.
  * We therefore declare the functions we need ourselves, rather than trying to

lib/common/entropy_common.c

@@ -43,8 +43,14 @@ static U32 FSE_ctz(U32 val)
     assert(val != 0);
     {
 #   if defined(_MSC_VER)   /* Visual */
-        unsigned long r=0;
-        return _BitScanForward(&r, val) ? (unsigned)r : 0;
+        if (val != 0) {
+            unsigned long r;
+            _BitScanForward(&r, val);
+            return (unsigned)r;
+        } else {
+            /* Should not reach this code path */
+            __assume(0);
+        }
 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* GCC Intrinsic */
         return __builtin_ctz(val);
 #   elif defined(__ICCARM__)    /* IAR Intrinsic */
@@ -217,7 +223,7 @@ static size_t FSE_readNCount_body_default(
 }
 
 #if DYNAMIC_BMI2
-TARGET_ATTRIBUTE("bmi2") static size_t FSE_readNCount_body_bmi2(
+BMI2_TARGET_ATTRIBUTE static size_t FSE_readNCount_body_bmi2(
         short* normalizedCounter, unsigned* maxSVPtr, unsigned* tableLogPtr,
         const void* headerBuffer, size_t hbSize)
 {
@@ -299,7 +305,7 @@ HUF_readStats_body(BYTE* huffWeight, size_t hwSize, U32* rankStats,
     ZSTD_memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32));
     weightTotal = 0;
     {   U32 n; for (n=0; n<oSize; n++) {
-            if (huffWeight[n] >= HUF_TABLELOG_MAX) return ERROR(corruption_detected);
+            if (huffWeight[n] > HUF_TABLELOG_MAX) return ERROR(corruption_detected);
             rankStats[huffWeight[n]]++;
             weightTotal += (1 << huffWeight[n]) >> 1;
     }   }
@@ -337,7 +343,7 @@ static size_t HUF_readStats_body_default(BYTE* huffWeight, size_t hwSize, U32* r
 }
 
 #if DYNAMIC_BMI2
-static TARGET_ATTRIBUTE("bmi2") size_t HUF_readStats_body_bmi2(BYTE* huffWeight, size_t hwSize, U32* rankStats,
+static BMI2_TARGET_ATTRIBUTE size_t HUF_readStats_body_bmi2(BYTE* huffWeight, size_t hwSize, U32* rankStats,
                      U32* nbSymbolsPtr, U32* tableLogPtr,
                      const void* src, size_t srcSize,
                      void* workSpace, size_t wkspSize)

lib/common/error_private.c

@@ -27,7 +27,7 @@ const char* ERR_getErrorString(ERR_enum code)
     case PREFIX(version_unsupported): return "Version not supported";
     case PREFIX(frameParameter_unsupported): return "Unsupported frame parameter";
     case PREFIX(frameParameter_windowTooLarge): return "Frame requires too much memory for decoding";
-    case PREFIX(corruption_detected): return "Corrupted block detected";
+    case PREFIX(corruption_detected): return "Data corruption detected";
     case PREFIX(checksum_wrong): return "Restored data doesn't match checksum";
     case PREFIX(parameter_unsupported): return "Unsupported parameter";
     case PREFIX(parameter_outOfBound): return "Parameter is out of bound";

lib/common/error_private.h

@@ -22,6 +22,8 @@ extern "C" {
 *  Dependencies
 ******************************************/
 #include "../zstd_errors.h"  /* enum list */
+#include "compiler.h"
+#include "debug.h"
 #include "zstd_deps.h"       /* size_t */
 
 
@@ -73,6 +75,83 @@ ERR_STATIC const char* ERR_getErrorName(size_t code)
     return ERR_getErrorString(ERR_getErrorCode(code));
 }
 
+/**
+ * Ignore: this is an internal helper.
+ *
+ * This is a helper function to help force C99-correctness during compilation.
+ * Under strict compilation modes, variadic macro arguments can't be empty.
+ * However, variadic function arguments can be. Using a function therefore lets
+ * us statically check that at least one (string) argument was passed,
+ * independent of the compilation flags.
+ */
+static INLINE_KEYWORD UNUSED_ATTR
+void _force_has_format_string(const char *format, ...) {
+  (void)format;
+}
+
+/**
+ * Ignore: this is an internal helper.
+ *
+ * We want to force this function invocation to be syntactically correct, but
+ * we don't want to force runtime evaluation of its arguments.
+ */
+#define _FORCE_HAS_FORMAT_STRING(...) \
+  if (0) { \
+    _force_has_format_string(__VA_ARGS__); \
+  }
+
+#define ERR_QUOTE(str) #str
+
+/**
+ * Return the specified error if the condition evaluates to true.
+ *
+ * In debug modes, prints additional information.
+ * In order to do that (particularly, printing the conditional that failed),
+ * this can't just wrap RETURN_ERROR().
+ */
+#define RETURN_ERROR_IF(cond, err, ...) \
+  if (cond) { \
+    RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
+           __FILE__, __LINE__, ERR_QUOTE(cond), ERR_QUOTE(ERROR(err))); \
+    _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
+    RAWLOG(3, ": " __VA_ARGS__); \
+    RAWLOG(3, "\n"); \
+    return ERROR(err); \
+  }
+
+/**
+ * Unconditionally return the specified error.
+ *
+ * In debug modes, prints additional information.
+ */
+#define RETURN_ERROR(err, ...) \
+  do { \
+    RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
+           __FILE__, __LINE__, ERR_QUOTE(ERROR(err))); \
+    _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
+    RAWLOG(3, ": " __VA_ARGS__); \
+    RAWLOG(3, "\n"); \
+    return ERROR(err); \
+  } while(0);
+
+/**
+ * If the provided expression evaluates to an error code, returns that error code.
+ *
+ * In debug modes, prints additional information.
+ */
+#define FORWARD_IF_ERROR(err, ...) \
+  do { \
+    size_t const err_code = (err); \
+    if (ERR_isError(err_code)) { \
+      RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
+             __FILE__, __LINE__, ERR_QUOTE(err), ERR_getErrorName(err_code)); \
+      _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
+      RAWLOG(3, ": " __VA_ARGS__); \
+      RAWLOG(3, "\n"); \
+      return err_code; \
+    } \
+  } while(0);
+
 #if defined (__cplusplus)
 }
 #endif

lib/common/fse.h

@@ -336,8 +336,9 @@ size_t FSE_buildCTable_rle (FSE_CTable* ct, unsigned char symbolValue);
 /* FSE_buildCTable_wksp() :
  * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`).
  * `wkspSize` must be >= `FSE_BUILD_CTABLE_WORKSPACE_SIZE_U32(maxSymbolValue, tableLog)` of `unsigned`.
+ * See FSE_buildCTable_wksp() for breakdown of workspace usage.
  */
-#define FSE_BUILD_CTABLE_WORKSPACE_SIZE_U32(maxSymbolValue, tableLog) (maxSymbolValue + 2 + (1ull << (tableLog - 2)))
+#define FSE_BUILD_CTABLE_WORKSPACE_SIZE_U32(maxSymbolValue, tableLog) (((maxSymbolValue + 2) + (1ull << (tableLog)))/2 + sizeof(U64)/sizeof(U32) /* additional 8 bytes for potential table overwrite */)
 #define FSE_BUILD_CTABLE_WORKSPACE_SIZE(maxSymbolValue, tableLog) (sizeof(unsigned) * FSE_BUILD_CTABLE_WORKSPACE_SIZE_U32(maxSymbolValue, tableLog))
 size_t FSE_buildCTable_wksp(FSE_CTable* ct, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize);
 

lib/common/fse_decompress.c

@@ -365,7 +365,7 @@ static size_t FSE_decompress_wksp_body_default(void* dst, size_t dstCapacity, co
 }
 
 #if DYNAMIC_BMI2
-TARGET_ATTRIBUTE("bmi2") static size_t FSE_decompress_wksp_body_bmi2(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, unsigned maxLog, void* workSpace, size_t wkspSize)
+BMI2_TARGET_ATTRIBUTE static size_t FSE_decompress_wksp_body_bmi2(void* dst, size_t dstCapacity, const void* cSrc, size_t cSrcSize, unsigned maxLog, void* workSpace, size_t wkspSize)
 {
     return FSE_decompress_wksp_body(dst, dstCapacity, cSrc, cSrcSize, maxLog, workSpace, wkspSize, 1);
 }

lib/common/huf.h

@@ -89,9 +89,9 @@ HUF_PUBLIC_API size_t HUF_compress2 (void* dst, size_t dstCapacity,
 
 /** HUF_compress4X_wksp() :
  *  Same as HUF_compress2(), but uses externally allocated `workSpace`.
- * `workspace` must have minimum alignment of 4, and be at least as large as HUF_WORKSPACE_SIZE */
-#define HUF_WORKSPACE_SIZE ((6 << 10) + 256)
-#define HUF_WORKSPACE_SIZE_U32 (HUF_WORKSPACE_SIZE / sizeof(U32))
+ * `workspace` must be at least as large as HUF_WORKSPACE_SIZE */
+#define HUF_WORKSPACE_SIZE ((8 << 10) + 512 /* sorting scratch space */)
+#define HUF_WORKSPACE_SIZE_U64 (HUF_WORKSPACE_SIZE / sizeof(U64))
 HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity,
                                      const void* src, size_t srcSize,
                                      unsigned maxSymbolValue, unsigned tableLog,
@@ -116,11 +116,11 @@ HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity,
 
 
 /* *** Constants *** */
-#define HUF_TABLELOG_MAX      12      /* max runtime value of tableLog (due to static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */
+#define HUF_TABLELOG_MAX      12      /* max runtime value of tableLog (due to static allocation); can be modified up to HUF_TABLELOG_ABSOLUTEMAX */
 #define HUF_TABLELOG_DEFAULT  11      /* default tableLog value when none specified */
 #define HUF_SYMBOLVALUE_MAX  255
 
-#define HUF_TABLELOG_ABSOLUTEMAX  15  /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
+#define HUF_TABLELOG_ABSOLUTEMAX  12  /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */
 #if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX)
 #  error "HUF_TABLELOG_MAX is too large !"
 #endif
@@ -136,15 +136,11 @@ HUF_PUBLIC_API size_t HUF_compress4X_wksp (void* dst, size_t dstCapacity,
 
 /* static allocation of HUF's Compression Table */
 /* this is a private definition, just exposed for allocation and strict aliasing purpose. never EVER access its members directly */
-struct HUF_CElt_s {
-  U16  val;
-  BYTE nbBits;
-};   /* typedef'd to HUF_CElt */
-typedef struct HUF_CElt_s HUF_CElt;   /* consider it an incomplete type */
-#define HUF_CTABLE_SIZE_U32(maxSymbolValue)   ((maxSymbolValue)+1)   /* Use tables of U32, for proper alignment */
-#define HUF_CTABLE_SIZE(maxSymbolValue)       (HUF_CTABLE_SIZE_U32(maxSymbolValue) * sizeof(U32))
+typedef size_t HUF_CElt;   /* consider it an incomplete type */
+#define HUF_CTABLE_SIZE_ST(maxSymbolValue)   ((maxSymbolValue)+2)   /* Use tables of size_t, for proper alignment */
+#define HUF_CTABLE_SIZE(maxSymbolValue)       (HUF_CTABLE_SIZE_ST(maxSymbolValue) * sizeof(size_t))
 #define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \
-    HUF_CElt name[HUF_CTABLE_SIZE_U32(maxSymbolValue)] /* no final ; */
+    HUF_CElt name[HUF_CTABLE_SIZE_ST(maxSymbolValue)] /* no final ; */
 
 /* static allocation of HUF's DTable */
 typedef U32 HUF_DTable;
@@ -194,6 +190,7 @@ size_t HUF_buildCTable (HUF_CElt* CTable, const unsigned* count, unsigned maxSym
 size_t HUF_writeCTable (void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog);
 size_t HUF_writeCTable_wksp(void* dst, size_t maxDstSize, const HUF_CElt* CTable, unsigned maxSymbolValue, unsigned huffLog, void* workspace, size_t workspaceSize);
 size_t HUF_compress4X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
+size_t HUF_compress4X_usingCTable_bmi2(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int bmi2);
 size_t HUF_estimateCompressedSize(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
 int HUF_validateCTable(const HUF_CElt* CTable, const unsigned* count, unsigned maxSymbolValue);
 
@@ -206,12 +203,13 @@ typedef enum {
  *  Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
  *  If it uses hufTable it does not modify hufTable or repeat.
  *  If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
- *  If preferRepeat then the old table will always be used if valid. */
+ *  If preferRepeat then the old table will always be used if valid.
+ *  If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
 size_t HUF_compress4X_repeat(void* dst, size_t dstSize,
                        const void* src, size_t srcSize,
                        unsigned maxSymbolValue, unsigned tableLog,
                        void* workSpace, size_t wkspSize,    /**< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
-                       HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2);
+                       HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2, unsigned suspectUncompressible);
 
 /** HUF_buildCTable_wksp() :
  *  Same as HUF_buildCTable(), but using externally allocated scratch buffer.
@@ -249,11 +247,10 @@ size_t HUF_readStats_wksp(BYTE* huffWeight, size_t hwSize,
  *  Loading a CTable saved with HUF_writeCTable() */
 size_t HUF_readCTable (HUF_CElt* CTable, unsigned* maxSymbolValuePtr, const void* src, size_t srcSize, unsigned *hasZeroWeights);
 
-/** HUF_getNbBits() :
+/** HUF_getNbBitsFromCTable() :
  *  Read nbBits from CTable symbolTable, for symbol `symbolValue` presumed <= HUF_SYMBOLVALUE_MAX
- *  Note 1 : is not inlined, as HUF_CElt definition is private
- *  Note 2 : const void* used, so that it can provide a statically allocated table as argument (which uses type U32) */
-U32 HUF_getNbBits(const void* symbolTable, U32 symbolValue);
+ *  Note 1 : is not inlined, as HUF_CElt definition is private */
+U32 HUF_getNbBitsFromCTable(const HUF_CElt* symbolTable, U32 symbolValue);
 
 /*
  * HUF_decompress() does the following:
@@ -305,18 +302,20 @@ size_t HUF_decompress4X2_usingDTable(void* dst, size_t maxDstSize, const void* c
 /* ====================== */
 
 size_t HUF_compress1X (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog);
-size_t HUF_compress1X_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize);  /**< `workSpace` must be a table of at least HUF_WORKSPACE_SIZE_U32 unsigned */
+size_t HUF_compress1X_wksp (void* dst, size_t dstSize, const void* src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void* workSpace, size_t wkspSize);  /**< `workSpace` must be a table of at least HUF_WORKSPACE_SIZE_U64 U64 */
 size_t HUF_compress1X_usingCTable(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable);
+size_t HUF_compress1X_usingCTable_bmi2(void* dst, size_t dstSize, const void* src, size_t srcSize, const HUF_CElt* CTable, int bmi2);
 /** HUF_compress1X_repeat() :
  *  Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none.
  *  If it uses hufTable it does not modify hufTable or repeat.
  *  If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used.
- *  If preferRepeat then the old table will always be used if valid. */
+ *  If preferRepeat then the old table will always be used if valid.
+ *  If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
 size_t HUF_compress1X_repeat(void* dst, size_t dstSize,
                        const void* src, size_t srcSize,
                        unsigned maxSymbolValue, unsigned tableLog,
                        void* workSpace, size_t wkspSize,   /**< `workSpace` must be aligned on 4-bytes boundaries, `wkspSize` must be >= HUF_WORKSPACE_SIZE */
-                       HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2);
+                       HUF_CElt* hufTable, HUF_repeat* repeat, int preferRepeat, int bmi2, unsigned suspectUncompressible);
 
 size_t HUF_decompress1X1 (void* dst, size_t dstSize, const void* cSrc, size_t cSrcSize);   /* single-symbol decoder */
 #ifndef HUF_FORCE_DECOMPRESS_X1
@@ -354,6 +353,9 @@ size_t HUF_decompress4X_hufOnly_wksp_bmi2(HUF_DTable* dctx, void* dst, size_t ds
 #ifndef HUF_FORCE_DECOMPRESS_X2
 size_t HUF_readDTableX1_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int bmi2);
 #endif
+#ifndef HUF_FORCE_DECOMPRESS_X1
+size_t HUF_readDTableX2_wksp_bmi2(HUF_DTable* DTable, const void* src, size_t srcSize, void* workSpace, size_t wkspSize, int bmi2);
+#endif
 
 #endif /* HUF_STATIC_LINKING_ONLY */
 

lib/common/mem.h

@@ -51,6 +51,8 @@ extern "C" {
 #    include <stdint.h> /* intptr_t */
 #  endif
   typedef   uint8_t BYTE;
+  typedef   uint8_t U8;
+  typedef    int8_t S8;
   typedef  uint16_t U16;
   typedef   int16_t S16;
   typedef  uint32_t U32;
@@ -63,6 +65,8 @@ extern "C" {
 #  error "this implementation requires char to be exactly 8-bit type"
 #endif
   typedef unsigned char      BYTE;
+  typedef unsigned char      U8;
+  typedef   signed char      S8;
 #if USHRT_MAX != 65535
 #  error "this implementation requires short to be exactly 16-bit type"
 #endif
@@ -153,8 +157,22 @@ MEM_STATIC unsigned MEM_64bits(void) { return sizeof(size_t)==8; }
 
 MEM_STATIC unsigned MEM_isLittleEndian(void)
 {
+#if defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
+    return 1;
+#elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && (__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
+    return 0;
+#elif defined(__clang__) && __LITTLE_ENDIAN__
+    return 1;
+#elif defined(__clang__) && __BIG_ENDIAN__
+    return 0;
+#elif defined(_MSC_VER) && (_M_AMD64 || _M_IX86)
+    return 1;
+#elif defined(__DMC__) && defined(_M_IX86)
+    return 1;
+#else
     const union { U32 u; BYTE c[4]; } one = { 1 };   /* don't use static : performance detrimental  */
     return one.c[0];
+#endif
 }
 
 #if defined(MEM_FORCE_MEMORY_ACCESS) && (MEM_FORCE_MEMORY_ACCESS==2)

lib/common/pool.c

@@ -86,7 +86,7 @@ static void* POOL_thread(void* opaque) {
         {   POOL_job const job = ctx->queue[ctx->queueHead];
             ctx->queueHead = (ctx->queueHead + 1) % ctx->queueSize;
             ctx->numThreadsBusy++;
-            ctx->queueEmpty = ctx->queueHead == ctx->queueTail;
+            ctx->queueEmpty = (ctx->queueHead == ctx->queueTail);
             /* Unlock the mutex, signal a pusher, and run the job */
             ZSTD_pthread_cond_signal(&ctx->queuePushCond);
             ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
@@ -96,15 +96,14 @@ static void* POOL_thread(void* opaque) {
             /* If the intended queue size was 0, signal after finishing job */
             ZSTD_pthread_mutex_lock(&ctx->queueMutex);
             ctx->numThreadsBusy--;
-            if (ctx->queueSize == 1) {
-                ZSTD_pthread_cond_signal(&ctx->queuePushCond);
-            }
+            ZSTD_pthread_cond_signal(&ctx->queuePushCond);
             ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
         }
     }  /* for (;;) */
     assert(0);  /* Unreachable */
 }
 
+/* ZSTD_createThreadPool() : public access point */
 POOL_ctx* ZSTD_createThreadPool(size_t numThreads) {
     return POOL_create (numThreads, 0);
 }
@@ -114,7 +113,8 @@ POOL_ctx* POOL_create(size_t numThreads, size_t queueSize) {
 }
 
 POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize,
-                               ZSTD_customMem customMem) {
+                               ZSTD_customMem customMem)
+{
     POOL_ctx* ctx;
     /* Check parameters */
     if (!numThreads) { return NULL; }
@@ -188,11 +188,22 @@ void POOL_free(POOL_ctx *ctx) {
     ZSTD_customFree(ctx, ctx->customMem);
 }
 
+/*! POOL_joinJobs() :
+ *  Waits for all queued jobs to finish executing.
+ */
+void POOL_joinJobs(POOL_ctx* ctx) {
+    ZSTD_pthread_mutex_lock(&ctx->queueMutex);
+    while(!ctx->queueEmpty || ctx->numThreadsBusy > 0) {
+        ZSTD_pthread_cond_wait(&ctx->queuePushCond, &ctx->queueMutex);
+    }
+    ZSTD_pthread_mutex_unlock(&ctx->queueMutex);
+}
+
 void ZSTD_freeThreadPool (ZSTD_threadPool* pool) {
   POOL_free (pool);
 }
 
-size_t POOL_sizeof(POOL_ctx *ctx) {
+size_t POOL_sizeof(const POOL_ctx* ctx) {
     if (ctx==NULL) return 0;  /* supports sizeof NULL */
     return sizeof(*ctx)
         + ctx->queueSize * sizeof(POOL_job)
@@ -257,7 +268,8 @@ static int isQueueFull(POOL_ctx const* ctx) {
 }
 
 
-static void POOL_add_internal(POOL_ctx* ctx, POOL_function function, void *opaque)
+static void
+POOL_add_internal(POOL_ctx* ctx, POOL_function function, void *opaque)
 {
     POOL_job const job = {function, opaque};
     assert(ctx != NULL);
@@ -313,7 +325,9 @@ POOL_ctx* POOL_create(size_t numThreads, size_t queueSize) {
     return POOL_create_advanced(numThreads, queueSize, ZSTD_defaultCMem);
 }
 
-POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize, ZSTD_customMem customMem) {
+POOL_ctx*
+POOL_create_advanced(size_t numThreads, size_t queueSize, ZSTD_customMem customMem)
+{
     (void)numThreads;
     (void)queueSize;
     (void)customMem;
@@ -325,6 +339,11 @@ void POOL_free(POOL_ctx* ctx) {
     (void)ctx;
 }
 
+void POOL_joinJobs(POOL_ctx* ctx){
+    assert(!ctx || ctx == &g_poolCtx);
+    (void)ctx;
+}
+
 int POOL_resize(POOL_ctx* ctx, size_t numThreads) {
     (void)ctx; (void)numThreads;
     return 0;
@@ -341,7 +360,7 @@ int POOL_tryAdd(POOL_ctx* ctx, POOL_function function, void* opaque) {
     return 1;
 }
 
-size_t POOL_sizeof(POOL_ctx* ctx) {
+size_t POOL_sizeof(const POOL_ctx* ctx) {
     if (ctx==NULL) return 0;  /* supports sizeof NULL */
     assert(ctx == &g_poolCtx);
     return sizeof(*ctx);

lib/common/pool.h

@@ -38,6 +38,12 @@ POOL_ctx* POOL_create_advanced(size_t numThreads, size_t queueSize,
  */
 void POOL_free(POOL_ctx* ctx);
 
+
+/*! POOL_joinJobs() :
+ *  Waits for all queued jobs to finish executing.
+ */
+void POOL_joinJobs(POOL_ctx* ctx);
+
 /*! POOL_resize() :
  *  Expands or shrinks pool's number of threads.
  *  This is more efficient than releasing + creating a new context,
@@ -53,7 +59,7 @@ int POOL_resize(POOL_ctx* ctx, size_t numThreads);
  * @return threadpool memory usage
  *  note : compatible with NULL (returns 0 in this case)
  */
-size_t POOL_sizeof(POOL_ctx* ctx);
+size_t POOL_sizeof(const POOL_ctx* ctx);
 
 /*! POOL_function :
  *  The function type that can be added to a thread pool.
@@ -70,7 +76,7 @@ void POOL_add(POOL_ctx* ctx, POOL_function function, void* opaque);
 
 
 /*! POOL_tryAdd() :
- *  Add the job `function(opaque)` to thread pool _if_ a worker is available.
+ *  Add the job `function(opaque)` to thread pool _if_ a queue slot is available.
  *  Returns immediately even if not (does not block).
  * @return : 1 if successful, 0 if not.
  */

lib/common/portability_macros.h

@@ -0,0 +1,148 @@
+/*
+ * Copyright (c) Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+#ifndef ZSTD_PORTABILITY_MACROS_H
+#define ZSTD_PORTABILITY_MACROS_H
+
+/**
+ * This header file contains macro defintions to support portability.
+ * This header is shared between C and ASM code, so it MUST only
+ * contain macro definitions. It MUST not contain any C code.
+ *
+ * This header ONLY defines macros to detect platforms/feature support.
+ *
+ */
+
+
+/* compat. with non-clang compilers */
+#ifndef __has_attribute
+  #define __has_attribute(x) 0
+#endif
+
+/* compat. with non-clang compilers */
+#ifndef __has_builtin
+#  define __has_builtin(x) 0
+#endif
+
+/* compat. with non-clang compilers */
+#ifndef __has_feature
+#  define __has_feature(x) 0
+#endif
+
+/* detects whether we are being compiled under msan */
+#ifndef ZSTD_MEMORY_SANITIZER
+#  if __has_feature(memory_sanitizer)
+#    define ZSTD_MEMORY_SANITIZER 1
+#  else
+#    define ZSTD_MEMORY_SANITIZER 0
+#  endif
+#endif
+
+/* detects whether we are being compiled under asan */
+#ifndef ZSTD_ADDRESS_SANITIZER
+#  if __has_feature(address_sanitizer)
+#    define ZSTD_ADDRESS_SANITIZER 1
+#  elif defined(__SANITIZE_ADDRESS__)
+#    define ZSTD_ADDRESS_SANITIZER 1
+#  else
+#    define ZSTD_ADDRESS_SANITIZER 0
+#  endif
+#endif
+
+/* detects whether we are being compiled under dfsan */
+#ifndef ZSTD_DATAFLOW_SANITIZER
+# if __has_feature(dataflow_sanitizer)
+#  define ZSTD_DATAFLOW_SANITIZER 1
+# else
+#  define ZSTD_DATAFLOW_SANITIZER 0
+# endif
+#endif
+
+/* Mark the internal assembly functions as hidden  */
+#ifdef __ELF__
+# define ZSTD_HIDE_ASM_FUNCTION(func) .hidden func
+#else
+# define ZSTD_HIDE_ASM_FUNCTION(func)
+#endif
+
+/* Enable runtime BMI2 dispatch based on the CPU.
+ * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
+ */
+#ifndef DYNAMIC_BMI2
+  #if ((defined(__clang__) && __has_attribute(__target__)) \
+      || (defined(__GNUC__) \
+          && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)))) \
+      && (defined(__x86_64__) || defined(_M_X64)) \
+      && !defined(__BMI2__)
+  #  define DYNAMIC_BMI2 1
+  #else
+  #  define DYNAMIC_BMI2 0
+  #endif
+#endif
+
+/**
+ * Only enable assembly for GNUC comptabile compilers,
+ * because other platforms may not support GAS assembly syntax.
+ *
+ * Only enable assembly for Linux / MacOS, other platforms may
+ * work, but they haven't been tested. This could likely be
+ * extended to BSD systems.
+ *
+ * Disable assembly when MSAN is enabled, because MSAN requires
+ * 100% of code to be instrumented to work.
+ */
+#if defined(__GNUC__)
+#  if defined(__linux__) || defined(__linux) || defined(__APPLE__)
+#    if ZSTD_MEMORY_SANITIZER
+#      define ZSTD_ASM_SUPPORTED 0
+#    elif ZSTD_DATAFLOW_SANITIZER
+#      define ZSTD_ASM_SUPPORTED 0
+#    else
+#      define ZSTD_ASM_SUPPORTED 1
+#    endif
+#  else
+#    define ZSTD_ASM_SUPPORTED 0
+#  endif
+#else
+#  define ZSTD_ASM_SUPPORTED 0
+#endif
+
+/**
+ * Determines whether we should enable assembly for x86-64
+ * with BMI2.
+ *
+ * Enable if all of the following conditions hold:
+ * - ASM hasn't been explicitly disabled by defining ZSTD_DISABLE_ASM
+ * - Assembly is supported
+ * - We are compiling for x86-64 and either:
+ *   - DYNAMIC_BMI2 is enabled
+ *   - BMI2 is supported at compile time
+ */
+#if !defined(ZSTD_DISABLE_ASM) &&                                 \
+    ZSTD_ASM_SUPPORTED &&                                         \
+    defined(__x86_64__) &&                                        \
+    (DYNAMIC_BMI2 || defined(__BMI2__))
+# define ZSTD_ENABLE_ASM_X86_64_BMI2 1
+#else
+# define ZSTD_ENABLE_ASM_X86_64_BMI2 0
+#endif
+
+/*
+ * For x86 ELF targets, add .note.gnu.property section for Intel CET in
+ * assembly sources when CET is enabled.
+ */
+#if defined(__ELF__) && (defined(__x86_64__) || defined(__i386__)) \
+    && defined(__has_include)
+# if __has_include(<cet.h>)
+#  include <cet.h>
+# endif
+#endif
+
+#endif /* ZSTD_PORTABILITY_MACROS_H */

lib/common/xxhash.c

@@ -5,7 +5,7 @@
  *  You can contact the author at :
  *  - xxHash homepage: http://www.xxhash.com
  *  - xxHash source repository : https://github.com/Cyan4973/xxHash
- * 
+ *
  * This source code is licensed under both the BSD-style license (found in the
  * LICENSE file in the root directory of this source tree) and the GPLv2 (found
  * in the COPYING file in the root directory of this source tree).
@@ -13,812 +13,12 @@
 */
 
 
-/* *************************************
-*  Tuning parameters
-***************************************/
-/*!XXH_FORCE_MEMORY_ACCESS :
- * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
- * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
- * The below switch allow to select different access method for improved performance.
- * Method 0 (default) : use `memcpy()`. Safe and portable.
- * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
- *            This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
- * Method 2 : direct access. This method doesn't depend on compiler but violate C standard.
- *            It can generate buggy code on targets which do not support unaligned memory accesses.
- *            But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
- * See http://stackoverflow.com/a/32095106/646947 for details.
- * Prefer these methods in priority order (0 > 1 > 2)
+
+/*
+ * xxhash.c instantiates functions defined in xxhash.h
  */
-#ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
-#  if (defined(__INTEL_COMPILER) && !defined(WIN32)) || \
-  (defined(__GNUC__) && ( defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__) )) || \
-  defined(__ICCARM__)
-#    define XXH_FORCE_MEMORY_ACCESS 1
-#  endif
-#endif
 
-/*!XXH_ACCEPT_NULL_INPUT_POINTER :
- * If the input pointer is a null pointer, xxHash default behavior is to trigger a memory access error, since it is a bad pointer.
- * When this option is enabled, xxHash output for null input pointers will be the same as a null-length input.
- * By default, this option is disabled. To enable it, uncomment below define :
- */
-/* #define XXH_ACCEPT_NULL_INPUT_POINTER 1 */
+#define XXH_STATIC_LINKING_ONLY   /* access advanced declarations */
+#define XXH_IMPLEMENTATION   /* access definitions */
 
-/*!XXH_FORCE_NATIVE_FORMAT :
- * By default, xxHash library provides endian-independent Hash values, based on little-endian convention.
- * Results are therefore identical for little-endian and big-endian CPU.
- * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format.
- * Should endian-independence be of no importance for your application, you may set the #define below to 1,
- * to improve speed for Big-endian CPU.
- * This option has no impact on Little_Endian CPU.
- */
-#ifndef XXH_FORCE_NATIVE_FORMAT   /* can be defined externally */
-#  define XXH_FORCE_NATIVE_FORMAT 0
-#endif
-
-/*!XXH_FORCE_ALIGN_CHECK :
- * This is a minor performance trick, only useful with lots of very small keys.
- * It means : check for aligned/unaligned input.
- * The check costs one initial branch per hash; set to 0 when the input data
- * is guaranteed to be aligned.
- */
-#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
-#  if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
-#    define XXH_FORCE_ALIGN_CHECK 0
-#  else
-#    define XXH_FORCE_ALIGN_CHECK 1
-#  endif
-#endif
-
-
-/* *************************************
-*  Includes & Memory related functions
-***************************************/
-/* Modify the local functions below should you wish to use some other memory routines */
-/* for ZSTD_malloc(), ZSTD_free() */
-#define ZSTD_DEPS_NEED_MALLOC
-#include "zstd_deps.h"  /* size_t, ZSTD_malloc, ZSTD_free, ZSTD_memcpy */
-static void* XXH_malloc(size_t s) { return ZSTD_malloc(s); }
-static void  XXH_free  (void* p)  { ZSTD_free(p); }
-static void* XXH_memcpy(void* dest, const void* src, size_t size) { return ZSTD_memcpy(dest,src,size); }
-
-#ifndef XXH_STATIC_LINKING_ONLY
-#  define XXH_STATIC_LINKING_ONLY
-#endif
 #include "xxhash.h"
-
-
-/* *************************************
-*  Compiler Specific Options
-***************************************/
-#include "compiler.h"
-
-
-/* *************************************
-*  Basic Types
-***************************************/
-#include "mem.h"  /* BYTE, U32, U64, size_t */
-
-#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==2))
-
-/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
-static U32 XXH_read32(const void* memPtr) { return *(const U32*) memPtr; }
-static U64 XXH_read64(const void* memPtr) { return *(const U64*) memPtr; }
-
-#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS==1))
-
-/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
-/* currently only defined for gcc and icc */
-typedef union { U32 u32; U64 u64; } __attribute__((packed)) unalign;
-
-static U32 XXH_read32(const void* ptr) { return ((const unalign*)ptr)->u32; }
-static U64 XXH_read64(const void* ptr) { return ((const unalign*)ptr)->u64; }
-
-#else
-
-/* portable and safe solution. Generally efficient.
- * see : http://stackoverflow.com/a/32095106/646947
- */
-
-static U32 XXH_read32(const void* memPtr)
-{
-    U32 val;
-    ZSTD_memcpy(&val, memPtr, sizeof(val));
-    return val;
-}
-
-static U64 XXH_read64(const void* memPtr)
-{
-    U64 val;
-    ZSTD_memcpy(&val, memPtr, sizeof(val));
-    return val;
-}
-
-#endif   /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
-
-
-/* ****************************************
-*  Compiler-specific Functions and Macros
-******************************************/
-#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
-
-/* Note : although _rotl exists for minGW (GCC under windows), performance seems poor */
-#if defined(_MSC_VER)
-#  define XXH_rotl32(x,r) _rotl(x,r)
-#  define XXH_rotl64(x,r) _rotl64(x,r)
-#else
-#if defined(__ICCARM__)
-#  include <intrinsics.h>
-#  define XXH_rotl32(x,r) __ROR(x,(32 - r))
-#else
-#  define XXH_rotl32(x,r) ((x << r) | (x >> (32 - r)))
-#endif
-#  define XXH_rotl64(x,r) ((x << r) | (x >> (64 - r)))
-#endif
-
-#if defined(_MSC_VER)     /* Visual Studio */
-#  define XXH_swap32 _byteswap_ulong
-#  define XXH_swap64 _byteswap_uint64
-#elif GCC_VERSION >= 403
-#  define XXH_swap32 __builtin_bswap32
-#  define XXH_swap64 __builtin_bswap64
-#else
-static U32 XXH_swap32 (U32 x)
-{
-    return  ((x << 24) & 0xff000000 ) |
-            ((x <<  8) & 0x00ff0000 ) |
-            ((x >>  8) & 0x0000ff00 ) |
-            ((x >> 24) & 0x000000ff );
-}
-static U64 XXH_swap64 (U64 x)
-{
-    return  ((x << 56) & 0xff00000000000000ULL) |
-            ((x << 40) & 0x00ff000000000000ULL) |
-            ((x << 24) & 0x0000ff0000000000ULL) |
-            ((x << 8)  & 0x000000ff00000000ULL) |
-            ((x >> 8)  & 0x00000000ff000000ULL) |
-            ((x >> 24) & 0x0000000000ff0000ULL) |
-            ((x >> 40) & 0x000000000000ff00ULL) |
-            ((x >> 56) & 0x00000000000000ffULL);
-}
-#endif
-
-
-/* *************************************
-*  Architecture Macros
-***************************************/
-typedef enum { XXH_bigEndian=0, XXH_littleEndian=1 } XXH_endianess;
-
-/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */
-#ifndef XXH_CPU_LITTLE_ENDIAN
-    static const int g_one = 1;
-#   define XXH_CPU_LITTLE_ENDIAN   (*(const char*)(&g_one))
-#endif
-
-
-/* ***************************
-*  Memory reads
-*****************************/
-typedef enum { XXH_aligned, XXH_unaligned } XXH_alignment;
-
-FORCE_INLINE_TEMPLATE U32 XXH_readLE32_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
-{
-    if (align==XXH_unaligned)
-        return endian==XXH_littleEndian ? XXH_read32(ptr) : XXH_swap32(XXH_read32(ptr));
-    else
-        return endian==XXH_littleEndian ? *(const U32*)ptr : XXH_swap32(*(const U32*)ptr);
-}
-
-FORCE_INLINE_TEMPLATE U32 XXH_readLE32(const void* ptr, XXH_endianess endian)
-{
-    return XXH_readLE32_align(ptr, endian, XXH_unaligned);
-}
-
-static U32 XXH_readBE32(const void* ptr)
-{
-    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap32(XXH_read32(ptr)) : XXH_read32(ptr);
-}
-
-FORCE_INLINE_TEMPLATE U64 XXH_readLE64_align(const void* ptr, XXH_endianess endian, XXH_alignment align)
-{
-    if (align==XXH_unaligned)
-        return endian==XXH_littleEndian ? XXH_read64(ptr) : XXH_swap64(XXH_read64(ptr));
-    else
-        return endian==XXH_littleEndian ? *(const U64*)ptr : XXH_swap64(*(const U64*)ptr);
-}
-
-FORCE_INLINE_TEMPLATE U64 XXH_readLE64(const void* ptr, XXH_endianess endian)
-{
-    return XXH_readLE64_align(ptr, endian, XXH_unaligned);
-}
-
-static U64 XXH_readBE64(const void* ptr)
-{
-    return XXH_CPU_LITTLE_ENDIAN ? XXH_swap64(XXH_read64(ptr)) : XXH_read64(ptr);
-}
-
-
-/* *************************************
-*  Macros
-***************************************/
-#define XXH_STATIC_ASSERT(c)   { enum { XXH_static_assert = 1/(int)(!!(c)) }; }    /* use only *after* variable declarations */
-
-
-/* *************************************
-*  Constants
-***************************************/
-static const U32 PRIME32_1 = 2654435761U;
-static const U32 PRIME32_2 = 2246822519U;
-static const U32 PRIME32_3 = 3266489917U;
-static const U32 PRIME32_4 =  668265263U;
-static const U32 PRIME32_5 =  374761393U;
-
-static const U64 PRIME64_1 = 11400714785074694791ULL;
-static const U64 PRIME64_2 = 14029467366897019727ULL;
-static const U64 PRIME64_3 =  1609587929392839161ULL;
-static const U64 PRIME64_4 =  9650029242287828579ULL;
-static const U64 PRIME64_5 =  2870177450012600261ULL;
-
-XXH_PUBLIC_API unsigned XXH_versionNumber (void) { return XXH_VERSION_NUMBER; }
-
-
-/* **************************
-*  Utils
-****************************/
-XXH_PUBLIC_API void XXH32_copyState(XXH32_state_t* restrict dstState, const XXH32_state_t* restrict srcState)
-{
-    ZSTD_memcpy(dstState, srcState, sizeof(*dstState));
-}
-
-XXH_PUBLIC_API void XXH64_copyState(XXH64_state_t* restrict dstState, const XXH64_state_t* restrict srcState)
-{
-    ZSTD_memcpy(dstState, srcState, sizeof(*dstState));
-}
-
-
-/* ***************************
-*  Simple Hash Functions
-*****************************/
-
-static U32 XXH32_round(U32 seed, U32 input)
-{
-    seed += input * PRIME32_2;
-    seed  = XXH_rotl32(seed, 13);
-    seed *= PRIME32_1;
-    return seed;
-}
-
-FORCE_INLINE_TEMPLATE U32 XXH32_endian_align(const void* input, size_t len, U32 seed, XXH_endianess endian, XXH_alignment align)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* bEnd = p + len;
-    U32 h32;
-#define XXH_get32bits(p) XXH_readLE32_align(p, endian, align)
-
-#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (p==NULL) {
-        len=0;
-        bEnd=p=(const BYTE*)(size_t)16;
-    }
-#endif
-
-    if (len>=16) {
-        const BYTE* const limit = bEnd - 16;
-        U32 v1 = seed + PRIME32_1 + PRIME32_2;
-        U32 v2 = seed + PRIME32_2;
-        U32 v3 = seed + 0;
-        U32 v4 = seed - PRIME32_1;
-
-        do {
-            v1 = XXH32_round(v1, XXH_get32bits(p)); p+=4;
-            v2 = XXH32_round(v2, XXH_get32bits(p)); p+=4;
-            v3 = XXH32_round(v3, XXH_get32bits(p)); p+=4;
-            v4 = XXH32_round(v4, XXH_get32bits(p)); p+=4;
-        } while (p<=limit);
-
-        h32 = XXH_rotl32(v1, 1) + XXH_rotl32(v2, 7) + XXH_rotl32(v3, 12) + XXH_rotl32(v4, 18);
-    } else {
-        h32  = seed + PRIME32_5;
-    }
-
-    h32 += (U32) len;
-
-    while (p+4<=bEnd) {
-        h32 += XXH_get32bits(p) * PRIME32_3;
-        h32  = XXH_rotl32(h32, 17) * PRIME32_4 ;
-        p+=4;
-    }
-
-    while (p<bEnd) {
-        h32 += (*p) * PRIME32_5;
-        h32 = XXH_rotl32(h32, 11) * PRIME32_1 ;
-        p++;
-    }
-
-    h32 ^= h32 >> 15;
-    h32 *= PRIME32_2;
-    h32 ^= h32 >> 13;
-    h32 *= PRIME32_3;
-    h32 ^= h32 >> 16;
-
-    return h32;
-}
-
-
-XXH_PUBLIC_API unsigned int XXH32 (const void* input, size_t len, unsigned int seed)
-{
-#if 0
-    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH32_CREATESTATE_STATIC(state);
-    XXH32_reset(state, seed);
-    XXH32_update(state, input, len);
-    return XXH32_digest(state);
-#else
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if (XXH_FORCE_ALIGN_CHECK) {
-        if ((((size_t)input) & 3) == 0) {   /* Input is 4-bytes aligned, leverage the speed benefit */
-            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-                return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-            else
-                return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }   }
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
-    else
-        return XXH32_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
-#endif
-}
-
-
-static U64 XXH64_round(U64 acc, U64 input)
-{
-    acc += input * PRIME64_2;
-    acc  = XXH_rotl64(acc, 31);
-    acc *= PRIME64_1;
-    return acc;
-}
-
-static U64 XXH64_mergeRound(U64 acc, U64 val)
-{
-    val  = XXH64_round(0, val);
-    acc ^= val;
-    acc  = acc * PRIME64_1 + PRIME64_4;
-    return acc;
-}
-
-FORCE_INLINE_TEMPLATE U64 XXH64_endian_align(const void* input, size_t len, U64 seed, XXH_endianess endian, XXH_alignment align)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* const bEnd = p + len;
-    U64 h64;
-#define XXH_get64bits(p) XXH_readLE64_align(p, endian, align)
-
-#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (p==NULL) {
-        len=0;
-        bEnd=p=(const BYTE*)(size_t)32;
-    }
-#endif
-
-    if (len>=32) {
-        const BYTE* const limit = bEnd - 32;
-        U64 v1 = seed + PRIME64_1 + PRIME64_2;
-        U64 v2 = seed + PRIME64_2;
-        U64 v3 = seed + 0;
-        U64 v4 = seed - PRIME64_1;
-
-        do {
-            v1 = XXH64_round(v1, XXH_get64bits(p)); p+=8;
-            v2 = XXH64_round(v2, XXH_get64bits(p)); p+=8;
-            v3 = XXH64_round(v3, XXH_get64bits(p)); p+=8;
-            v4 = XXH64_round(v4, XXH_get64bits(p)); p+=8;
-        } while (p<=limit);
-
-        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
-        h64 = XXH64_mergeRound(h64, v1);
-        h64 = XXH64_mergeRound(h64, v2);
-        h64 = XXH64_mergeRound(h64, v3);
-        h64 = XXH64_mergeRound(h64, v4);
-
-    } else {
-        h64  = seed + PRIME64_5;
-    }
-
-    h64 += (U64) len;
-
-    while (p+8<=bEnd) {
-        U64 const k1 = XXH64_round(0, XXH_get64bits(p));
-        h64 ^= k1;
-        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
-        p+=8;
-    }
-
-    if (p+4<=bEnd) {
-        h64 ^= (U64)(XXH_get32bits(p)) * PRIME64_1;
-        h64 = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
-        p+=4;
-    }
-
-    while (p<bEnd) {
-        h64 ^= (*p) * PRIME64_5;
-        h64 = XXH_rotl64(h64, 11) * PRIME64_1;
-        p++;
-    }
-
-    h64 ^= h64 >> 33;
-    h64 *= PRIME64_2;
-    h64 ^= h64 >> 29;
-    h64 *= PRIME64_3;
-    h64 ^= h64 >> 32;
-
-    return h64;
-}
-
-
-XXH_PUBLIC_API unsigned long long XXH64 (const void* input, size_t len, unsigned long long seed)
-{
-#if 0
-    /* Simple version, good for code maintenance, but unfortunately slow for small inputs */
-    XXH64_CREATESTATE_STATIC(state);
-    XXH64_reset(state, seed);
-    XXH64_update(state, input, len);
-    return XXH64_digest(state);
-#else
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if (XXH_FORCE_ALIGN_CHECK) {
-        if ((((size_t)input) & 7)==0) {  /* Input is aligned, let's leverage the speed advantage */
-            if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-                return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_aligned);
-            else
-                return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_aligned);
-    }   }
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_endian_align(input, len, seed, XXH_littleEndian, XXH_unaligned);
-    else
-        return XXH64_endian_align(input, len, seed, XXH_bigEndian, XXH_unaligned);
-#endif
-}
-
-
-/* **************************************************
-*  Advanced Hash Functions
-****************************************************/
-
-XXH_PUBLIC_API XXH32_state_t* XXH32_createState(void)
-{
-    return (XXH32_state_t*)XXH_malloc(sizeof(XXH32_state_t));
-}
-XXH_PUBLIC_API XXH_errorcode XXH32_freeState(XXH32_state_t* statePtr)
-{
-    XXH_free(statePtr);
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API XXH64_state_t* XXH64_createState(void)
-{
-    return (XXH64_state_t*)XXH_malloc(sizeof(XXH64_state_t));
-}
-XXH_PUBLIC_API XXH_errorcode XXH64_freeState(XXH64_state_t* statePtr)
-{
-    XXH_free(statePtr);
-    return XXH_OK;
-}
-
-
-/*** Hash feed ***/
-
-XXH_PUBLIC_API XXH_errorcode XXH32_reset(XXH32_state_t* statePtr, unsigned int seed)
-{
-    XXH32_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
-    ZSTD_memset(&state, 0, sizeof(state)-4);   /* do not write into reserved, for future removal */
-    state.v1 = seed + PRIME32_1 + PRIME32_2;
-    state.v2 = seed + PRIME32_2;
-    state.v3 = seed + 0;
-    state.v4 = seed - PRIME32_1;
-    ZSTD_memcpy(statePtr, &state, sizeof(state));
-    return XXH_OK;
-}
-
-
-XXH_PUBLIC_API XXH_errorcode XXH64_reset(XXH64_state_t* statePtr, unsigned long long seed)
-{
-    XXH64_state_t state;   /* using a local state to memcpy() in order to avoid strict-aliasing warnings */
-    ZSTD_memset(&state, 0, sizeof(state)-8);   /* do not write into reserved, for future removal */
-    state.v1 = seed + PRIME64_1 + PRIME64_2;
-    state.v2 = seed + PRIME64_2;
-    state.v3 = seed + 0;
-    state.v4 = seed - PRIME64_1;
-    ZSTD_memcpy(statePtr, &state, sizeof(state));
-    return XXH_OK;
-}
-
-
-FORCE_INLINE_TEMPLATE XXH_errorcode XXH32_update_endian (XXH32_state_t* state, const void* input, size_t len, XXH_endianess endian)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* const bEnd = p + len;
-
-#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (input==NULL) return XXH_ERROR;
-#endif
-
-    state->total_len_32 += (unsigned)len;
-    state->large_len |= (len>=16) | (state->total_len_32>=16);
-
-    if (state->memsize + len < 16)  {   /* fill in tmp buffer */
-        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, len);
-        state->memsize += (unsigned)len;
-        return XXH_OK;
-    }
-
-    if (state->memsize) {   /* some data left from previous update */
-        XXH_memcpy((BYTE*)(state->mem32) + state->memsize, input, 16-state->memsize);
-        {   const U32* p32 = state->mem32;
-            state->v1 = XXH32_round(state->v1, XXH_readLE32(p32, endian)); p32++;
-            state->v2 = XXH32_round(state->v2, XXH_readLE32(p32, endian)); p32++;
-            state->v3 = XXH32_round(state->v3, XXH_readLE32(p32, endian)); p32++;
-            state->v4 = XXH32_round(state->v4, XXH_readLE32(p32, endian)); p32++;
-        }
-        p += 16-state->memsize;
-        state->memsize = 0;
-    }
-
-    if (p <= bEnd-16) {
-        const BYTE* const limit = bEnd - 16;
-        U32 v1 = state->v1;
-        U32 v2 = state->v2;
-        U32 v3 = state->v3;
-        U32 v4 = state->v4;
-
-        do {
-            v1 = XXH32_round(v1, XXH_readLE32(p, endian)); p+=4;
-            v2 = XXH32_round(v2, XXH_readLE32(p, endian)); p+=4;
-            v3 = XXH32_round(v3, XXH_readLE32(p, endian)); p+=4;
-            v4 = XXH32_round(v4, XXH_readLE32(p, endian)); p+=4;
-        } while (p<=limit);
-
-        state->v1 = v1;
-        state->v2 = v2;
-        state->v3 = v3;
-        state->v4 = v4;
-    }
-
-    if (p < bEnd) {
-        XXH_memcpy(state->mem32, p, (size_t)(bEnd-p));
-        state->memsize = (unsigned)(bEnd-p);
-    }
-
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API XXH_errorcode XXH32_update (XXH32_state_t* state_in, const void* input, size_t len)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_update_endian(state_in, input, len, XXH_littleEndian);
-    else
-        return XXH32_update_endian(state_in, input, len, XXH_bigEndian);
-}
-
-
-
-FORCE_INLINE_TEMPLATE U32 XXH32_digest_endian (const XXH32_state_t* state, XXH_endianess endian)
-{
-    const BYTE * p = (const BYTE*)state->mem32;
-    const BYTE* const bEnd = (const BYTE*)(state->mem32) + state->memsize;
-    U32 h32;
-
-    if (state->large_len) {
-        h32 = XXH_rotl32(state->v1, 1) + XXH_rotl32(state->v2, 7) + XXH_rotl32(state->v3, 12) + XXH_rotl32(state->v4, 18);
-    } else {
-        h32 = state->v3 /* == seed */ + PRIME32_5;
-    }
-
-    h32 += state->total_len_32;
-
-    while (p+4<=bEnd) {
-        h32 += XXH_readLE32(p, endian) * PRIME32_3;
-        h32  = XXH_rotl32(h32, 17) * PRIME32_4;
-        p+=4;
-    }
-
-    while (p<bEnd) {
-        h32 += (*p) * PRIME32_5;
-        h32  = XXH_rotl32(h32, 11) * PRIME32_1;
-        p++;
-    }
-
-    h32 ^= h32 >> 15;
-    h32 *= PRIME32_2;
-    h32 ^= h32 >> 13;
-    h32 *= PRIME32_3;
-    h32 ^= h32 >> 16;
-
-    return h32;
-}
-
-
-XXH_PUBLIC_API unsigned int XXH32_digest (const XXH32_state_t* state_in)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH32_digest_endian(state_in, XXH_littleEndian);
-    else
-        return XXH32_digest_endian(state_in, XXH_bigEndian);
-}
-
-
-
-/* **** XXH64 **** */
-
-FORCE_INLINE_TEMPLATE XXH_errorcode XXH64_update_endian (XXH64_state_t* state, const void* input, size_t len, XXH_endianess endian)
-{
-    const BYTE* p = (const BYTE*)input;
-    const BYTE* const bEnd = p + len;
-
-#ifdef XXH_ACCEPT_NULL_INPUT_POINTER
-    if (input==NULL) return XXH_ERROR;
-#endif
-
-    state->total_len += len;
-
-    if (state->memsize + len < 32) {  /* fill in tmp buffer */
-        if (input != NULL) {
-            XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, len);
-        }
-        state->memsize += (U32)len;
-        return XXH_OK;
-    }
-
-    if (state->memsize) {   /* tmp buffer is full */
-        XXH_memcpy(((BYTE*)state->mem64) + state->memsize, input, 32-state->memsize);
-        state->v1 = XXH64_round(state->v1, XXH_readLE64(state->mem64+0, endian));
-        state->v2 = XXH64_round(state->v2, XXH_readLE64(state->mem64+1, endian));
-        state->v3 = XXH64_round(state->v3, XXH_readLE64(state->mem64+2, endian));
-        state->v4 = XXH64_round(state->v4, XXH_readLE64(state->mem64+3, endian));
-        p += 32-state->memsize;
-        state->memsize = 0;
-    }
-
-    if (p+32 <= bEnd) {
-        const BYTE* const limit = bEnd - 32;
-        U64 v1 = state->v1;
-        U64 v2 = state->v2;
-        U64 v3 = state->v3;
-        U64 v4 = state->v4;
-
-        do {
-            v1 = XXH64_round(v1, XXH_readLE64(p, endian)); p+=8;
-            v2 = XXH64_round(v2, XXH_readLE64(p, endian)); p+=8;
-            v3 = XXH64_round(v3, XXH_readLE64(p, endian)); p+=8;
-            v4 = XXH64_round(v4, XXH_readLE64(p, endian)); p+=8;
-        } while (p<=limit);
-
-        state->v1 = v1;
-        state->v2 = v2;
-        state->v3 = v3;
-        state->v4 = v4;
-    }
-
-    if (p < bEnd) {
-        XXH_memcpy(state->mem64, p, (size_t)(bEnd-p));
-        state->memsize = (unsigned)(bEnd-p);
-    }
-
-    return XXH_OK;
-}
-
-XXH_PUBLIC_API XXH_errorcode XXH64_update (XXH64_state_t* state_in, const void* input, size_t len)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_update_endian(state_in, input, len, XXH_littleEndian);
-    else
-        return XXH64_update_endian(state_in, input, len, XXH_bigEndian);
-}
-
-
-
-FORCE_INLINE_TEMPLATE U64 XXH64_digest_endian (const XXH64_state_t* state, XXH_endianess endian)
-{
-    const BYTE * p = (const BYTE*)state->mem64;
-    const BYTE* const bEnd = (const BYTE*)state->mem64 + state->memsize;
-    U64 h64;
-
-    if (state->total_len >= 32) {
-        U64 const v1 = state->v1;
-        U64 const v2 = state->v2;
-        U64 const v3 = state->v3;
-        U64 const v4 = state->v4;
-
-        h64 = XXH_rotl64(v1, 1) + XXH_rotl64(v2, 7) + XXH_rotl64(v3, 12) + XXH_rotl64(v4, 18);
-        h64 = XXH64_mergeRound(h64, v1);
-        h64 = XXH64_mergeRound(h64, v2);
-        h64 = XXH64_mergeRound(h64, v3);
-        h64 = XXH64_mergeRound(h64, v4);
-    } else {
-        h64  = state->v3 + PRIME64_5;
-    }
-
-    h64 += (U64) state->total_len;
-
-    while (p+8<=bEnd) {
-        U64 const k1 = XXH64_round(0, XXH_readLE64(p, endian));
-        h64 ^= k1;
-        h64  = XXH_rotl64(h64,27) * PRIME64_1 + PRIME64_4;
-        p+=8;
-    }
-
-    if (p+4<=bEnd) {
-        h64 ^= (U64)(XXH_readLE32(p, endian)) * PRIME64_1;
-        h64  = XXH_rotl64(h64, 23) * PRIME64_2 + PRIME64_3;
-        p+=4;
-    }
-
-    while (p<bEnd) {
-        h64 ^= (*p) * PRIME64_5;
-        h64  = XXH_rotl64(h64, 11) * PRIME64_1;
-        p++;
-    }
-
-    h64 ^= h64 >> 33;
-    h64 *= PRIME64_2;
-    h64 ^= h64 >> 29;
-    h64 *= PRIME64_3;
-    h64 ^= h64 >> 32;
-
-    return h64;
-}
-
-
-XXH_PUBLIC_API unsigned long long XXH64_digest (const XXH64_state_t* state_in)
-{
-    XXH_endianess endian_detected = (XXH_endianess)XXH_CPU_LITTLE_ENDIAN;
-
-    if ((endian_detected==XXH_littleEndian) || XXH_FORCE_NATIVE_FORMAT)
-        return XXH64_digest_endian(state_in, XXH_littleEndian);
-    else
-        return XXH64_digest_endian(state_in, XXH_bigEndian);
-}
-
-
-/* **************************
-*  Canonical representation
-****************************/
-
-/*! Default XXH result types are basic unsigned 32 and 64 bits.
-*   The canonical representation follows human-readable write convention, aka big-endian (large digits first).
-*   These functions allow transformation of hash result into and from its canonical format.
-*   This way, hash values can be written into a file or buffer, and remain comparable across different systems and programs.
-*/
-
-XXH_PUBLIC_API void XXH32_canonicalFromHash(XXH32_canonical_t* dst, XXH32_hash_t hash)
-{
-    XXH_STATIC_ASSERT(sizeof(XXH32_canonical_t) == sizeof(XXH32_hash_t));
-    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap32(hash);
-    ZSTD_memcpy(dst, &hash, sizeof(*dst));
-}
-
-XXH_PUBLIC_API void XXH64_canonicalFromHash(XXH64_canonical_t* dst, XXH64_hash_t hash)
-{
-    XXH_STATIC_ASSERT(sizeof(XXH64_canonical_t) == sizeof(XXH64_hash_t));
-    if (XXH_CPU_LITTLE_ENDIAN) hash = XXH_swap64(hash);
-    ZSTD_memcpy(dst, &hash, sizeof(*dst));
-}
-
-XXH_PUBLIC_API XXH32_hash_t XXH32_hashFromCanonical(const XXH32_canonical_t* src)
-{
-    return XXH_readBE32(src);
-}
-
-XXH_PUBLIC_API XXH64_hash_t XXH64_hashFromCanonical(const XXH64_canonical_t* src)
-{
-    return XXH_readBE64(src);
-}

lib/common/zstd_internal.h

@@ -19,10 +19,8 @@
 /*-*************************************
 *  Dependencies
 ***************************************/
-#if !defined(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
-#include <arm_neon.h>
-#endif
 #include "compiler.h"
+#include "cpu.h"
 #include "mem.h"
 #include "debug.h"                 /* assert, DEBUGLOG, RAWLOG, g_debuglevel */
 #include "error_private.h"
@@ -60,81 +58,7 @@ extern "C" {
 #undef MAX
 #define MIN(a,b) ((a)<(b) ? (a) : (b))
 #define MAX(a,b) ((a)>(b) ? (a) : (b))
-
-/**
- * Ignore: this is an internal helper.
- *
- * This is a helper function to help force C99-correctness during compilation.
- * Under strict compilation modes, variadic macro arguments can't be empty.
- * However, variadic function arguments can be. Using a function therefore lets
- * us statically check that at least one (string) argument was passed,
- * independent of the compilation flags.
- */
-static INLINE_KEYWORD UNUSED_ATTR
-void _force_has_format_string(const char *format, ...) {
-  (void)format;
-}
-
-/**
- * Ignore: this is an internal helper.
- *
- * We want to force this function invocation to be syntactically correct, but
- * we don't want to force runtime evaluation of its arguments.
- */
-#define _FORCE_HAS_FORMAT_STRING(...) \
-  if (0) { \
-    _force_has_format_string(__VA_ARGS__); \
-  }
-
-/**
- * Return the specified error if the condition evaluates to true.
- *
- * In debug modes, prints additional information.
- * In order to do that (particularly, printing the conditional that failed),
- * this can't just wrap RETURN_ERROR().
- */
-#define RETURN_ERROR_IF(cond, err, ...) \
-  if (cond) { \
-    RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \
-           __FILE__, __LINE__, ZSTD_QUOTE(cond), ZSTD_QUOTE(ERROR(err))); \
-    _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
-    RAWLOG(3, ": " __VA_ARGS__); \
-    RAWLOG(3, "\n"); \
-    return ERROR(err); \
-  }
-
-/**
- * Unconditionally return the specified error.
- *
- * In debug modes, prints additional information.
- */
-#define RETURN_ERROR(err, ...) \
-  do { \
-    RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \
-           __FILE__, __LINE__, ZSTD_QUOTE(ERROR(err))); \
-    _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
-    RAWLOG(3, ": " __VA_ARGS__); \
-    RAWLOG(3, "\n"); \
-    return ERROR(err); \
-  } while(0);
-
-/**
- * If the provided expression evaluates to an error code, returns that error code.
- *
- * In debug modes, prints additional information.
- */
-#define FORWARD_IF_ERROR(err, ...) \
-  do { \
-    size_t const err_code = (err); \
-    if (ERR_isError(err_code)) { \
-      RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \
-             __FILE__, __LINE__, ZSTD_QUOTE(err), ERR_getErrorName(err_code)); \
-      _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \
-      RAWLOG(3, ": " __VA_ARGS__); \
-      RAWLOG(3, "\n"); \
-      return err_code; \
-    } \
-  } while(0);
+#define BOUNDED(min,val,max) (MAX(min,MIN(val,max)))
 
 
 /*-*************************************
@@ -143,7 +67,6 @@ void _force_has_format_string(const char *format, ...) {
 #define ZSTD_OPT_NUM    (1<<12)
 
 #define ZSTD_REP_NUM      3                 /* number of repcodes */
-#define ZSTD_REP_MOVE     (ZSTD_REP_NUM-1)
 static UNUSED_ATTR const U32 repStartValue[ZSTD_REP_NUM] = { 1, 4, 8 };
 
 #define KB *(1 <<10)
@@ -172,7 +95,6 @@ typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e;
 #define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */
 #define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */)   /* for a non-null block */
 
-#define HufLog 12
 typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e;
 
 #define LONGNBSEQ 0x7F00
@@ -180,6 +102,7 @@ typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingTy
 #define MINMATCH 3
 
 #define Litbits  8
+#define LitHufLog 11
 #define MaxLit ((1<<Litbits) - 1)
 #define MaxML   52
 #define MaxLL   35
@@ -195,7 +118,7 @@ typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingTy
 /* Each table cannot take more than #symbols * FSELog bits */
 #define ZSTD_MAX_FSE_HEADERS_SIZE (((MaxML + 1) * MLFSELog + (MaxLL + 1) * LLFSELog + (MaxOff + 1) * OffFSELog + 7) / 8)
 
-static UNUSED_ATTR const U32 LL_bits[MaxLL+1] = {
+static UNUSED_ATTR const U8 LL_bits[MaxLL+1] = {
      0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0,
      1, 1, 1, 1, 2, 2, 3, 3,
@@ -212,7 +135,7 @@ static UNUSED_ATTR const S16 LL_defaultNorm[MaxLL+1] = {
 #define LL_DEFAULTNORMLOG 6  /* for static allocation */
 static UNUSED_ATTR const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG;
 
-static UNUSED_ATTR const U32 ML_bits[MaxML+1] = {
+static UNUSED_ATTR const U8 ML_bits[MaxML+1] = {
      0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0,
@@ -247,19 +170,30 @@ static UNUSED_ATTR const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG;
 *  Shared functions to include for inlining
 *********************************************/
 static void ZSTD_copy8(void* dst, const void* src) {
-#if !defined(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
+#if defined(ZSTD_ARCH_ARM_NEON)
     vst1_u8((uint8_t*)dst, vld1_u8((const uint8_t*)src));
 #else
     ZSTD_memcpy(dst, src, 8);
 #endif
 }
-
 #define COPY8(d,s) { ZSTD_copy8(d,s); d+=8; s+=8; }
+
+/* Need to use memmove here since the literal buffer can now be located within
+   the dst buffer. In circumstances where the op "catches up" to where the
+   literal buffer is, there can be partial overlaps in this call on the final
+   copy if the literal is being shifted by less than 16 bytes. */
 static void ZSTD_copy16(void* dst, const void* src) {
-#if !defined(ZSTD_NO_INTRINSICS) && defined(__ARM_NEON)
+#if defined(ZSTD_ARCH_ARM_NEON)
     vst1q_u8((uint8_t*)dst, vld1q_u8((const uint8_t*)src));
+#elif defined(ZSTD_ARCH_X86_SSE2)
+    _mm_storeu_si128((__m128i*)dst, _mm_loadu_si128((const __m128i*)src));
+#elif defined(__clang__)
+    ZSTD_memmove(dst, src, 16);
 #else
-    ZSTD_memcpy(dst, src, 16);
+    /* ZSTD_memmove is not inlined properly by gcc */
+    BYTE copy16_buf[16];
+    ZSTD_memcpy(copy16_buf, src, 16);
+    ZSTD_memcpy(dst, copy16_buf, 16);
 #endif
 }
 #define COPY16(d,s) { ZSTD_copy16(d,s); d+=16; s+=16; }
@@ -288,8 +222,6 @@ void ZSTD_wildcopy(void* dst, const void* src, ptrdiff_t length, ZSTD_overlap_e
     BYTE* op = (BYTE*)dst;
     BYTE* const oend = op + length;
 
-    assert(diff >= 8 || (ovtype == ZSTD_no_overlap && diff <= -WILDCOPY_VECLEN));
-
     if (ovtype == ZSTD_overlap_src_before_dst && diff < WILDCOPY_VECLEN) {
         /* Handle short offset copies. */
         do {
@@ -352,9 +284,9 @@ typedef enum {
 *  Private declarations
 *********************************************/
 typedef struct seqDef_s {
-    U32 offset;         /* offset == rawOffset + ZSTD_REP_NUM, or equivalently, offCode + 1 */
+    U32 offBase;   /* offBase == Offset + ZSTD_REP_NUM, or repcode 1,2,3 */
     U16 litLength;
-    U16 matchLength;
+    U16 mlBase;    /* mlBase == matchLength - MINMATCH */
 } seqDef;
 
 /* Controls whether seqStore has a single "long" litLength or matchLength. See seqStore_t. */
@@ -367,11 +299,11 @@ typedef enum {
 typedef struct {
     seqDef* sequencesStart;
     seqDef* sequences;      /* ptr to end of sequences */
-    BYTE* litStart;
-    BYTE* lit;              /* ptr to end of literals */
-    BYTE* llCode;
-    BYTE* mlCode;
-    BYTE* ofCode;
+    BYTE*  litStart;
+    BYTE*  lit;             /* ptr to end of literals */
+    BYTE*  llCode;
+    BYTE*  mlCode;
+    BYTE*  ofCode;
     size_t maxNbSeq;
     size_t maxNbLit;
 
@@ -396,7 +328,7 @@ MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore
 {
     ZSTD_sequenceLength seqLen;
     seqLen.litLength = seq->litLength;
-    seqLen.matchLength = seq->matchLength + MINMATCH;
+    seqLen.matchLength = seq->mlBase + MINMATCH;
     if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) {
         if (seqStore->longLengthType == ZSTD_llt_literalLength) {
             seqLen.litLength += 0xFFFF;
@@ -436,11 +368,17 @@ MEM_STATIC U32 ZSTD_highbit32(U32 val)   /* compress, dictBuilder, decodeCorpus
 #       if STATIC_BMI2 == 1
             return _lzcnt_u32(val)^31;
 #       else
-            unsigned long r=0;
-            return _BitScanReverse(&r, val) ? (unsigned)r : 0;
+            if (val != 0) {
+                unsigned long r;
+                _BitScanReverse(&r, val);
+                return (unsigned)r;
+            } else {
+                /* Should not reach this code path */
+                __assume(0);
+            }
 #       endif
 #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* GCC Intrinsic */
-        return __builtin_clz (val) ^ 31;
+        return (U32)__builtin_clz (val) ^ 31;
 #   elif defined(__ICCARM__)    /* IAR Intrinsic */
         return 31 - __CLZ(val);
 #   else   /* Software version */
@@ -456,6 +394,63 @@ MEM_STATIC U32 ZSTD_highbit32(U32 val)   /* compress, dictBuilder, decodeCorpus
     }
 }
 
+/**
+ * Counts the number of trailing zeros of a `size_t`.
+ * Most compilers should support CTZ as a builtin. A backup
+ * implementation is provided if the builtin isn't supported, but
+ * it may not be terribly efficient.
+ */
+MEM_STATIC unsigned ZSTD_countTrailingZeros(size_t val)
+{
+    if (MEM_64bits()) {
+#       if defined(_MSC_VER) && defined(_WIN64)
+#           if STATIC_BMI2
+                return _tzcnt_u64(val);
+#           else
+                if (val != 0) {
+                    unsigned long r;
+                    _BitScanForward64(&r, (U64)val);
+                    return (unsigned)r;
+                } else {
+                    /* Should not reach this code path */
+                    __assume(0);
+                }
+#           endif
+#       elif defined(__GNUC__) && (__GNUC__ >= 4)
+            return (unsigned)__builtin_ctzll((U64)val);
+#       else
+            static const int DeBruijnBytePos[64] = {  0,  1,  2,  7,  3, 13,  8, 19,
+                                                      4, 25, 14, 28,  9, 34, 20, 56,
+                                                      5, 17, 26, 54, 15, 41, 29, 43,
+                                                      10, 31, 38, 35, 21, 45, 49, 57,
+                                                      63,  6, 12, 18, 24, 27, 33, 55,
+                                                      16, 53, 40, 42, 30, 37, 44, 48,
+                                                      62, 11, 23, 32, 52, 39, 36, 47,
+                                                      61, 22, 51, 46, 60, 50, 59, 58 };
+            return DeBruijnBytePos[((U64)((val & -(long long)val) * 0x0218A392CDABBD3FULL)) >> 58];
+#       endif
+    } else { /* 32 bits */
+#       if defined(_MSC_VER)
+            if (val != 0) {
+                unsigned long r;
+                _BitScanForward(&r, (U32)val);
+                return (unsigned)r;
+            } else {
+                /* Should not reach this code path */
+                __assume(0);
+            }
+#       elif defined(__GNUC__) && (__GNUC__ >= 3)
+            return (unsigned)__builtin_ctz((U32)val);
+#       else
+            static const int DeBruijnBytePos[32] = {  0,  1, 28,  2, 29, 14, 24,  3,
+                                                     30, 22, 20, 15, 25, 17,  4,  8,
+                                                     31, 27, 13, 23, 21, 19, 16,  7,
+                                                     26, 12, 18,  6, 11,  5, 10,  9 };
+            return DeBruijnBytePos[((U32)((val & -(S32)val) * 0x077CB531U)) >> 27];
+#       endif
+    }
+}
+
 
 /* ZSTD_invalidateRepCodes() :
  * ensures next compression will not use repcodes from previous block.
@@ -482,6 +477,14 @@ size_t ZSTD_getcBlockSize(const void* src, size_t srcSize,
 size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx* dctx, int* nbSeqPtr,
                        const void* src, size_t srcSize);
 
+/**
+ * @returns true iff the CPU supports dynamic BMI2 dispatch.
+ */
+MEM_STATIC int ZSTD_cpuSupportsBmi2(void)
+{
+    ZSTD_cpuid_t cpuid = ZSTD_cpuid();
+    return ZSTD_cpuid_bmi1(cpuid) && ZSTD_cpuid_bmi2(cpuid);
+}
 
 #if defined (__cplusplus)
 }

lib/common/zstd_trace.h

@@ -17,10 +17,19 @@ extern "C" {
 
 #include <stddef.h>
 
-/* weak symbol support */
-#if !defined(ZSTD_HAVE_WEAK_SYMBOLS) && defined(__GNUC__) && \
+/* weak symbol support
+ * For now, enable conservatively:
+ * - Only GNUC
+ * - Only ELF
+ * - Only x86-64 and i386
+ * Also, explicitly disable on platforms known not to work so they aren't
+ * forgotten in the future.
+ */
+#if !defined(ZSTD_HAVE_WEAK_SYMBOLS) && \
+    defined(__GNUC__) && defined(__ELF__) && \
+    (defined(__x86_64__) || defined(_M_X64) || defined(__i386__) || defined(_M_IX86)) && \
     !defined(__APPLE__) && !defined(_WIN32) && !defined(__MINGW32__) && \
-    !defined(__CYGWIN__)
+    !defined(__CYGWIN__) && !defined(_AIX)
 #  define ZSTD_HAVE_WEAK_SYMBOLS 1
 #else
 #  define ZSTD_HAVE_WEAK_SYMBOLS 0

lib/compress/clevels.h

@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) Yann Collet, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under both the BSD-style license (found in the
+ * LICENSE file in the root directory of this source tree) and the GPLv2 (found
+ * in the COPYING file in the root directory of this source tree).
+ * You may select, at your option, one of the above-listed licenses.
+ */
+
+#ifndef ZSTD_CLEVELS_H
+#define ZSTD_CLEVELS_H
+
+#define ZSTD_STATIC_LINKING_ONLY  /* ZSTD_compressionParameters  */
+#include "../zstd.h"
+
+/*-=====  Pre-defined compression levels  =====-*/
+
+#define ZSTD_MAX_CLEVEL     22
+
+#ifdef __GNUC__
+__attribute__((__unused__))
+#endif
+
+static const ZSTD_compressionParameters ZSTD_defaultCParameters[4][ZSTD_MAX_CLEVEL+1] = {
+{   /* "default" - for any srcSize > 256 KB */
+    /* W,  C,  H,  S,  L, TL, strat */
+    { 19, 12, 13,  1,  6,  1, ZSTD_fast    },  /* base for negative levels */
+    { 19, 13, 14,  1,  7,  0, ZSTD_fast    },  /* level  1 */
+    { 20, 15, 16,  1,  6,  0, ZSTD_fast    },  /* level  2 */
+    { 21, 16, 17,  1,  5,  0, ZSTD_dfast   },  /* level  3 */
+    { 21, 18, 18,  1,  5,  0, ZSTD_dfast   },  /* level  4 */
+    { 21, 18, 19,  3,  5,  2, ZSTD_greedy  },  /* level  5 */
+    { 21, 18, 19,  3,  5,  4, ZSTD_lazy    },  /* level  6 */
+    { 21, 19, 20,  4,  5,  8, ZSTD_lazy    },  /* level  7 */
+    { 21, 19, 20,  4,  5, 16, ZSTD_lazy2   },  /* level  8 */
+    { 22, 20, 21,  4,  5, 16, ZSTD_lazy2   },  /* level  9 */
+    { 22, 21, 22,  5,  5, 16, ZSTD_lazy2   },  /* level 10 */
+    { 22, 21, 22,  6,  5, 16, ZSTD_lazy2   },  /* level 11 */
+    { 22, 22, 23,  6,  5, 32, ZSTD_lazy2   },  /* level 12 */
+    { 22, 22, 22,  4,  5, 32, ZSTD_btlazy2 },  /* level 13 */
+    { 22, 22, 23,  5,  5, 32, ZSTD_btlazy2 },  /* level 14 */
+    { 22, 23, 23,  6,  5, 32, ZSTD_btlazy2 },  /* level 15 */
+    { 22, 22, 22,  5,  5, 48, ZSTD_btopt   },  /* level 16 */
+    { 23, 23, 22,  5,  4, 64, ZSTD_btopt   },  /* level 17 */
+    { 23, 23, 22,  6,  3, 64, ZSTD_btultra },  /* level 18 */
+    { 23, 24, 22,  7,  3,256, ZSTD_btultra2},  /* level 19 */
+    { 25, 25, 23,  7,  3,256, ZSTD_btultra2},  /* level 20 */
+    { 26, 26, 24,  7,  3,512, ZSTD_btultra2},  /* level 21 */
+    { 27, 27, 25,  9,  3,999, ZSTD_btultra2},  /* level 22 */
+},
+{   /* for srcSize <= 256 KB */
+    /* W,  C,  H,  S,  L,  T, strat */
+    { 18, 12, 13,  1,  5,  1, ZSTD_fast    },  /* base for negative levels */
+    { 18, 13, 14,  1,  6,  0, ZSTD_fast    },  /* level  1 */
+    { 18, 14, 14,  1,  5,  0, ZSTD_dfast   },  /* level  2 */
+    { 18, 16, 16,  1,  4,  0, ZSTD_dfast   },  /* level  3 */
+    { 18, 16, 17,  3,  5,  2, ZSTD_greedy  },  /* level  4.*/
+    { 18, 17, 18,  5,  5,  2, ZSTD_greedy  },  /* level  5.*/
+    { 18, 18, 19,  3,  5,  4, ZSTD_lazy    },  /* level  6.*/
+    { 18, 18, 19,  4,  4,  4, ZSTD_lazy    },  /* level  7 */
+    { 18, 18, 19,  4,  4,  8, ZSTD_lazy2   },  /* level  8 */
+    { 18, 18, 19,  5,  4,  8, ZSTD_lazy2   },  /* level  9 */
+    { 18, 18, 19,  6,  4,  8, ZSTD_lazy2   },  /* level 10 */
+    { 18, 18, 19,  5,  4, 12, ZSTD_btlazy2 },  /* level 11.*/
+    { 18, 19, 19,  7,  4, 12, ZSTD_btlazy2 },  /* level 12.*/
+    { 18, 18, 19,  4,  4, 16, ZSTD_btopt   },  /* level 13 */
+    { 18, 18, 19,  4,  3, 32, ZSTD_btopt   },  /* level 14.*/
+    { 18, 18, 19,  6,  3,128, ZSTD_btopt   },  /* level 15.*/
+    { 18, 19, 19,  6,  3,128, ZSTD_btultra },  /* level 16.*/
+    { 18, 19, 19,  8,  3,256, ZSTD_btultra },  /* level 17.*/
+    { 18, 19, 19,  6,  3,128, ZSTD_btultra2},  /* level 18.*/
+    { 18, 19, 19,  8,  3,256, ZSTD_btultra2},  /* level 19.*/
+    { 18, 19, 19, 10,  3,512, ZSTD_btultra2},  /* level 20.*/
+    { 18, 19, 19, 12,  3,512, ZSTD_btultra2},  /* level 21.*/
+    { 18, 19, 19, 13,  3,999, ZSTD_btultra2},  /* level 22.*/
+},
+{   /* for srcSize <= 128 KB */
+    /* W,  C,  H,  S,  L,  T, strat */
+    { 17, 12, 12,  1,  5,  1, ZSTD_fast    },  /* base for negative levels */
+    { 17, 12, 13,  1,  6,  0, ZSTD_fast    },  /* level  1 */
+    { 17, 13, 15,  1,  5,  0, ZSTD_fast    },  /* level  2 */
+    { 17, 15, 16,  2,  5,  0, ZSTD_dfast   },  /* level  3 */
+    { 17, 17, 17,  2,  4,  0, ZSTD_dfast   },  /* level  4 */
+    { 17, 16, 17,  3,  4,  2, ZSTD_greedy  },  /* level  5 */
+    { 17, 16, 17,  3,  4,  4, ZSTD_lazy    },  /* level  6 */
+    { 17, 16, 17,  3,  4,  8, ZSTD_lazy2   },  /* level  7 */
+    { 17, 16, 17,  4,  4,  8, ZSTD_lazy2   },  /* level  8 */
+    { 17, 16, 17,  5,  4,  8, ZSTD_lazy2   },  /* level  9 */
+    { 17, 16, 17,  6,  4,  8, ZSTD_lazy2   },  /* level 10 */
+    { 17, 17, 17,  5,  4,  8, ZSTD_btlazy2 },  /* level 11 */
+    { 17, 18, 17,  7,  4, 12, ZSTD_btlazy2 },  /* level 12 */
+    { 17, 18, 17,  3,  4, 12, ZSTD_btopt   },  /* level 13.*/
+    { 17, 18, 17,  4,  3, 32, ZSTD_btopt   },  /* level 14.*/
+    { 17, 18, 17,  6,  3,256, ZSTD_btopt   },  /* level 15.*/
+    { 17, 18, 17,  6,  3,128, ZSTD_btultra },  /* level 16.*/
+    { 17, 18, 17,  8,  3,256, ZSTD_btultra },  /* level 17.*/
+    { 17, 18, 17, 10,  3,512, ZSTD_btultra },  /* level 18.*/
+    { 17, 18, 17,  5,  3,256, ZSTD_btultra2},  /* level 19.*/
+    { 17, 18, 17,  7,  3,512, ZSTD_btultra2},  /* level 20.*/
+    { 17, 18, 17,  9,  3,512, ZSTD_btultra2},  /* level 21.*/
+    { 17, 18, 17, 11,  3,999, ZSTD_btultra2},  /* level 22.*/
+},
+{   /* for srcSize <= 16 KB */
+    /* W,  C,  H,  S,  L,  T, strat */
+    { 14, 12, 13,  1,  5,  1, ZSTD_fast    },  /* base for negative levels */
+    { 14, 14, 15,  1,  5,  0, ZSTD_fast    },  /* level  1 */
+    { 14, 14, 15,  1,  4,  0, ZSTD_fast    },  /* level  2 */
+    { 14, 14, 15,  2,  4,  0, ZSTD_dfast   },  /* level  3 */
+    { 14, 14, 14,  4,  4,  2, ZSTD_greedy  },  /* level  4 */
+    { 14, 14, 14,  3,  4,  4, ZSTD_lazy    },  /* level  5.*/
+    { 14, 14, 14,  4,  4,  8, ZSTD_lazy2   },  /* level  6 */
+    { 14, 14, 14,  6,  4,  8, ZSTD_lazy2   },  /* level  7 */
+    { 14, 14, 14,  8,  4,  8, ZSTD_lazy2   },  /* level  8.*/
+    { 14, 15, 14,  5,  4,  8, ZSTD_btlazy2 },  /* level  9.*/
+    { 14, 15, 14,  9,  4,  8, ZSTD_btlazy2 },  /* level 10.*/
+    { 14, 15, 14,  3,  4, 12, ZSTD_btopt   },  /* level 11.*/
+    { 14, 15, 14,  4,  3, 24, ZSTD_btopt   },  /* level 12.*/
+    { 14, 15, 14,  5,  3, 32, ZSTD_btultra },  /* level 13.*/
+    { 14, 15, 15,  6,  3, 64, ZSTD_btultra },  /* level 14.*/
+    { 14, 15, 15,  7,  3,256, ZSTD_btultra },  /* level 15.*/
+    { 14, 15, 15,  5,  3, 48, ZSTD_btultra2},  /* level 16.*/
+    { 14, 15, 15,  6,  3,128, ZSTD_btultra2},  /* level 17.*/
+    { 14, 15, 15,  7,  3,256, ZSTD_btultra2},  /* level 18.*/
+    { 14, 15, 15,  8,  3,256, ZSTD_btultra2},  /* level 19.*/
+    { 14, 15, 15,  8,  3,512, ZSTD_btultra2},  /* level 20.*/
+    { 14, 15, 15,  9,  3,512, ZSTD_btultra2},  /* level 21.*/
+    { 14, 15, 15, 10,  3,999, ZSTD_btultra2},  /* level 22.*/
+},
+};
+
+
+
+#endif  /* ZSTD_CLEVELS_H */

lib/compress/fse_compress.c

@@ -75,13 +75,14 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct,
     void* const FSCT = ((U32*)ptr) + 1 /* header */ + (tableLog ? tableSize>>1 : 1) ;
     FSE_symbolCompressionTransform* const symbolTT = (FSE_symbolCompressionTransform*) (FSCT);
     U32 const step = FSE_TABLESTEP(tableSize);
+    U32 const maxSV1 = maxSymbolValue+1;
 
-    U32* cumul = (U32*)workSpace;
-    FSE_FUNCTION_TYPE* tableSymbol = (FSE_FUNCTION_TYPE*)(cumul + (maxSymbolValue + 2));
+    U16* cumul = (U16*)workSpace;   /* size = maxSV1 */
+    FSE_FUNCTION_TYPE* const tableSymbol = (FSE_FUNCTION_TYPE*)(cumul + (maxSV1+1));  /* size = tableSize */
 
     U32 highThreshold = tableSize-1;
 
-    if ((size_t)workSpace & 3) return ERROR(GENERIC); /* Must be 4 byte aligned */
+    assert(((size_t)workSpace & 1) == 0);  /* Must be 2 bytes-aligned */
     if (FSE_BUILD_CTABLE_WORKSPACE_SIZE(maxSymbolValue, tableLog) > wkspSize) return ERROR(tableLog_tooLarge);
     /* CTable header */
     tableU16[-2] = (U16) tableLog;
@@ -98,20 +99,61 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct,
     /* symbol start positions */
     {   U32 u;
         cumul[0] = 0;
-        for (u=1; u <= maxSymbolValue+1; u++) {
+        for (u=1; u <= maxSV1; u++) {
             if (normalizedCounter[u-1]==-1) {  /* Low proba symbol */
                 cumul[u] = cumul[u-1] + 1;
                 tableSymbol[highThreshold--] = (FSE_FUNCTION_TYPE)(u-1);
             } else {
-                cumul[u] = cumul[u-1] + normalizedCounter[u-1];
+                assert(normalizedCounter[u-1] >= 0);
+                cumul[u] = cumul[u-1] + (U16)normalizedCounter[u-1];
+                assert(cumul[u] >= cumul[u-1]);  /* no overflow */
         }   }
-        cumul[maxSymbolValue+1] = tableSize+1;
+        cumul[maxSV1] = (U16)(tableSize+1);
     }
 
     /* Spread symbols */
-    {   U32 position = 0;
+    if (highThreshold == tableSize - 1) {
+        /* Case for no low prob count symbols. Lay down 8 bytes at a time
+         * to reduce branch misses since we are operating on a small block
+         */
+        BYTE* const spread = tableSymbol + tableSize; /* size = tableSize + 8 (may write beyond tableSize) */
+        {   U64 const add = 0x0101010101010101ull;
+            size_t pos = 0;
+            U64 sv = 0;
+            U32 s;
+            for (s=0; s<maxSV1; ++s, sv += add) {
+                int i;
+                int const n = normalizedCounter[s];
+                MEM_write64(spread + pos, sv);
+                for (i = 8; i < n; i += 8) {
+                    MEM_write64(spread + pos + i, sv);
+                }
+                assert(n>=0);
+                pos += (size_t)n;
+            }
+        }
+        /* Spread symbols across the table. Lack of lowprob symbols means that
+         * we don't need variable sized inner loop, so we can unroll the loop and
+         * reduce branch misses.
+         */
+        {   size_t position = 0;
+            size_t s;
+            size_t const unroll = 2; /* Experimentally determined optimal unroll */
+            assert(tableSize % unroll == 0); /* FSE_MIN_TABLELOG is 5 */
+            for (s = 0; s < (size_t)tableSize; s += unroll) {
+                size_t u;
+                for (u = 0; u < unroll; ++u) {
+                    size_t const uPosition = (position + (u * step)) & tableMask;
+                    tableSymbol[uPosition] = spread[s + u];
+                }
+                position = (position + (unroll * step)) & tableMask;
+            }
+            assert(position == 0);   /* Must have initialized all positions */
+        }
+    } else {
+        U32 position = 0;
         U32 symbol;
-        for (symbol=0; symbol<=maxSymbolValue; symbol++) {
+        for (symbol=0; symbol<maxSV1; symbol++) {
             int nbOccurrences;
             int const freq = normalizedCounter[symbol];
             for (nbOccurrences=0; nbOccurrences<freq; nbOccurrences++) {
@@ -120,7 +162,6 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct,
                 while (position > highThreshold)
                     position = (position + step) & tableMask;   /* Low proba area */
         }   }
-
         assert(position==0);  /* Must have initialized all positions */
     }
 
@@ -144,16 +185,17 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct,
             case -1:
             case  1:
                 symbolTT[s].deltaNbBits = (tableLog << 16) - (1<<tableLog);
-                symbolTT[s].deltaFindState = total - 1;
+                assert(total <= INT_MAX);
+                symbolTT[s].deltaFindState = (int)(total - 1);
                 total ++;
                 break;
             default :
-                {
-                    U32 const maxBitsOut = tableLog - BIT_highbit32 (normalizedCounter[s]-1);
-                    U32 const minStatePlus = normalizedCounter[s] << maxBitsOut;
+                assert(normalizedCounter[s] > 1);
+                {   U32 const maxBitsOut = tableLog - BIT_highbit32 ((U32)normalizedCounter[s]-1);
+                    U32 const minStatePlus = (U32)normalizedCounter[s] << maxBitsOut;
                     symbolTT[s].deltaNbBits = (maxBitsOut << 16) - minStatePlus;
-                    symbolTT[s].deltaFindState = total - normalizedCounter[s];
-                    total +=  normalizedCounter[s];
+                    symbolTT[s].deltaFindState = (int)(total - (unsigned)normalizedCounter[s]);
+                    total +=  (unsigned)normalizedCounter[s];
     }   }   }   }
 
 #if 0  /* debug : symbol costs */
@@ -164,32 +206,26 @@ size_t FSE_buildCTable_wksp(FSE_CTable* ct,
                 symbol, normalizedCounter[symbol],
                 FSE_getMaxNbBits(symbolTT, symbol),
                 (double)FSE_bitCost(symbolTT, tableLog, symbol, 8) / 256);
-        }
-    }
+    }   }
 #endif
 
     return 0;
 }
 
-#ifndef ZSTD_NO_UNUSED_FUNCTIONS
-size_t FSE_buildCTable(FSE_CTable* ct, const short* normalizedCounter, unsigned maxSymbolValue, unsigned tableLog)
-{
-    FSE_FUNCTION_TYPE tableSymbol[FSE_MAX_TABLESIZE];   /* memset() is not necessary, even if static analyzer complain about it */
-    return FSE_buildCTable_wksp(ct, normalizedCounter, maxSymbolValue, tableLog, tableSymbol, sizeof(tableSymbol));
-}
-#endif
-
 
 
 #ifndef FSE_COMMONDEFS_ONLY
 
-
 /*-**************************************************************
 *  FSE NCount encoding
 ****************************************************************/
 size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog)
 {
-    size_t const maxHeaderSize = (((maxSymbolValue+1) * tableLog) >> 3) + 3;
+    size_t const maxHeaderSize = (((maxSymbolValue+1) * tableLog
+                                   + 4 /* bitCount initialized at 4 */
+                                   + 2 /* first two symbols may use one additional bit each */) / 8)
+                                    + 1 /* round up to whole nb bytes */
+                                    + 2 /* additional two bytes for bitstream flush */;
     return maxSymbolValue ? maxHeaderSize : FSE_NCOUNTBOUND;  /* maxSymbolValue==0 ? use default */
 }
 

lib/compress/zstd_compress_internal.h

@@ -63,7 +63,7 @@ typedef struct {
 } ZSTD_localDict;
 
 typedef struct {
-    HUF_CElt CTable[HUF_CTABLE_SIZE_U32(255)];
+    HUF_CElt CTable[HUF_CTABLE_SIZE_ST(255)];
     HUF_repeat repeatMode;
 } ZSTD_hufCTables_t;
 
@@ -129,7 +129,7 @@ size_t ZSTD_buildBlockEntropyStats(seqStore_t* seqStorePtr,
 *********************************/
 
 typedef struct {
-    U32 off;            /* Offset code (offset + ZSTD_REP_MOVE) for the match */
+    U32 off;            /* Offset sumtype code for the match, using ZSTD_storeSeq() format */
     U32 len;            /* Raw length of match */
 } ZSTD_match_t;
 
@@ -179,7 +179,7 @@ typedef struct {
     U32  offCodeSumBasePrice;    /* to compare to log2(offreq)  */
     ZSTD_OptPrice_e priceType;   /* prices can be determined dynamically, or follow a pre-defined cost structure */
     const ZSTD_entropyCTables_t* symbolCosts;  /* pre-calculated dictionary statistics */
-    ZSTD_literalCompressionMode_e literalCompressionMode;
+    ZSTD_paramSwitch_e literalCompressionMode;
 } optState_t;
 
 typedef struct {
@@ -199,6 +199,8 @@ typedef struct {
                                 */
 } ZSTD_window_t;
 
+#define ZSTD_WINDOW_START_INDEX 2
+
 typedef struct ZSTD_matchState_t ZSTD_matchState_t;
 
 #define ZSTD_ROW_HASH_CACHE_SIZE 8       /* Size of prefetching hash cache for row-based matchfinder */
@@ -264,7 +266,7 @@ typedef struct {
 } ldmState_t;
 
 typedef struct {
-    U32 enableLdm;          /* 1 if enable long distance matching */
+    ZSTD_paramSwitch_e enableLdm; /* ZSTD_ps_enable to enable LDM. ZSTD_ps_auto by default */
     U32 hashLog;            /* Log size of hashTable */
     U32 bucketSizeLog;      /* Log bucket size for collision resolution, at most 8 */
     U32 minMatchLength;     /* Minimum match length */
@@ -295,7 +297,7 @@ struct ZSTD_CCtx_params_s {
                                 * There is no guarantee that hint is close to actual source size */
 
     ZSTD_dictAttachPref_e attachDictPref;
-    ZSTD_literalCompressionMode_e literalCompressionMode;
+    ZSTD_paramSwitch_e literalCompressionMode;
 
     /* Multithreading: used to pass parameters to mtctx */
     int nbWorkers;
@@ -318,10 +320,10 @@ struct ZSTD_CCtx_params_s {
     int validateSequences;
 
     /* Block splitting */
-    int splitBlocks;
+    ZSTD_paramSwitch_e useBlockSplitter;
 
     /* Param for deciding whether to use row-based matchfinder */
-    ZSTD_useRowMatchFinderMode_e useRowMatchFinder;
+    ZSTD_paramSwitch_e useRowMatchFinder;
 
     /* Always load a dictionary in ext-dict mode (not prefix mode)? */
     int deterministicRefPrefix;
@@ -343,6 +345,22 @@ typedef enum {
     ZSTDb_buffered
 } ZSTD_buffered_policy_e;
 
+/**
+ * Struct that contains all elements of block splitter that should be allocated
+ * in a wksp.
+ */
+#define ZSTD_MAX_NB_BLOCK_SPLITS 196
+typedef struct {
+    seqStore_t fullSeqStoreChunk;
+    seqStore_t firstHalfSeqStore;
+    seqStore_t secondHalfSeqStore;
+    seqStore_t currSeqStore;
+    seqStore_t nextSeqStore;
+
+    U32 partitions[ZSTD_MAX_NB_BLOCK_SPLITS];
+    ZSTD_entropyCTablesMetadata_t entropyMetadata;
+} ZSTD_blockSplitCtx;
+
 struct ZSTD_CCtx_s {
     ZSTD_compressionStage_e stage;
     int cParamsChanged;                  /* == 1 if cParams(except wlog) or compression level are changed in requestedParams. Triggers transmission of new params to ZSTDMT (if available) then reset to 0. */
@@ -374,7 +392,7 @@ struct ZSTD_CCtx_s {
     ZSTD_blockState_t blockState;
     U32* entropyWorkspace;  /* entropy workspace of ENTROPY_WORKSPACE_SIZE bytes */
 
-    /* Wether we are streaming or not */
+    /* Whether we are streaming or not */
     ZSTD_buffered_policy_e bufferedPolicy;
 
     /* streaming */
@@ -408,6 +426,9 @@ struct ZSTD_CCtx_s {
 #if ZSTD_TRACE
     ZSTD_TraceCtx traceCtx;
 #endif
+
+    /* Workspace for block splitter */
+    ZSTD_blockSplitCtx blockSplitCtx;
 };
 
 typedef enum { ZSTD_dtlm_fast, ZSTD_dtlm_full } ZSTD_dictTableLoadMethod_e;
@@ -442,7 +463,7 @@ typedef enum {
 typedef size_t (*ZSTD_blockCompressor) (
         ZSTD_matchState_t* bs, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, ZSTD_useRowMatchFinderMode_e rowMatchfinderMode, ZSTD_dictMode_e dictMode);
+ZSTD_blockCompressor ZSTD_selectBlockCompressor(ZSTD_strategy strat, ZSTD_paramSwitch_e rowMatchfinderMode, ZSTD_dictMode_e dictMode);
 
 
 MEM_STATIC U32 ZSTD_LLcode(U32 litLength)
@@ -476,31 +497,6 @@ MEM_STATIC U32 ZSTD_MLcode(U32 mlBase)
     return (mlBase > 127) ? ZSTD_highbit32(mlBase) + ML_deltaCode : ML_Code[mlBase];
 }
 
-typedef struct repcodes_s {
-    U32 rep[3];
-} repcodes_t;
-
-MEM_STATIC repcodes_t ZSTD_updateRep(U32 const rep[3], U32 const offset, U32 const ll0)
-{
-    repcodes_t newReps;
-    if (offset >= ZSTD_REP_NUM) {  /* full offset */
-        newReps.rep[2] = rep[1];
-        newReps.rep[1] = rep[0];
-        newReps.rep[0] = offset - ZSTD_REP_MOVE;
-    } else {   /* repcode */
-        U32 const repCode = offset + ll0;
-        if (repCode > 0) {  /* note : if repCode==0, no change */
-            U32 const currentOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
-            newReps.rep[2] = (repCode >= 2) ? rep[1] : rep[2];
-            newReps.rep[1] = rep[0];
-            newReps.rep[0] = currentOffset;
-        } else {   /* repCode == 0 */
-            ZSTD_memcpy(&newReps, rep, sizeof(newReps));
-        }
-    }
-    return newReps;
-}
-
 /* ZSTD_cParam_withinBounds:
  * @return 1 if value is within cParam bounds,
  * 0 otherwise */
@@ -549,17 +545,17 @@ MEM_STATIC size_t ZSTD_minGain(size_t srcSize, ZSTD_strategy strat)
     return (srcSize >> minlog) + 2;
 }
 
-MEM_STATIC int ZSTD_disableLiteralsCompression(const ZSTD_CCtx_params* cctxParams)
+MEM_STATIC int ZSTD_literalsCompressionIsDisabled(const ZSTD_CCtx_params* cctxParams)
 {
     switch (cctxParams->literalCompressionMode) {
-    case ZSTD_lcm_huffman:
+    case ZSTD_ps_enable:
         return 0;
-    case ZSTD_lcm_uncompressed:
+    case ZSTD_ps_disable:
         return 1;
     default:
         assert(0 /* impossible: pre-validated */);
-        /* fall-through */
-    case ZSTD_lcm_auto:
+        ZSTD_FALLTHROUGH;
+    case ZSTD_ps_auto:
         return (cctxParams->cParams.strategy == ZSTD_fast) && (cctxParams->cParams.targetLength > 0);
     }
 }
@@ -569,7 +565,9 @@ MEM_STATIC int ZSTD_disableLiteralsCompression(const ZSTD_CCtx_params* cctxParam
  *  Only called when the sequence ends past ilimit_w, so it only needs to be optimized for single
  *  large copies.
  */
-static void ZSTD_safecopyLiterals(BYTE* op, BYTE const* ip, BYTE const* const iend, BYTE const* ilimit_w) {
+static void
+ZSTD_safecopyLiterals(BYTE* op, BYTE const* ip, BYTE const* const iend, BYTE const* ilimit_w)
+{
     assert(iend > ilimit_w);
     if (ip <= ilimit_w) {
         ZSTD_wildcopy(op, ip, ilimit_w - ip, ZSTD_no_overlap);
@@ -579,14 +577,28 @@ static void ZSTD_safecopyLiterals(BYTE* op, BYTE const* ip, BYTE const* const ie
     while (ip < iend) *op++ = *ip++;
 }
 
+
+#define REPCODE1_TO_OFFBASE REPCODE_TO_OFFBASE(1)
+#define REPCODE2_TO_OFFBASE REPCODE_TO_OFFBASE(2)
+#define REPCODE3_TO_OFFBASE REPCODE_TO_OFFBASE(3)
+#define REPCODE_TO_OFFBASE(r) (assert((r)>=1), assert((r)<=ZSTD_REP_NUM), (r)) /* accepts IDs 1,2,3 */
+#define OFFSET_TO_OFFBASE(o)  (assert((o)>0), o + ZSTD_REP_NUM)
+#define OFFBASE_IS_OFFSET(o)  ((o) > ZSTD_REP_NUM)
+#define OFFBASE_IS_REPCODE(o) ( 1 <= (o) && (o) <= ZSTD_REP_NUM)
+#define OFFBASE_TO_OFFSET(o)  (assert(OFFBASE_IS_OFFSET(o)), (o) - ZSTD_REP_NUM)
+#define OFFBASE_TO_REPCODE(o) (assert(OFFBASE_IS_REPCODE(o)), (o))  /* returns ID 1,2,3 */
+
 /*! ZSTD_storeSeq() :
- *  Store a sequence (litlen, litPtr, offCode and mlBase) into seqStore_t.
- *  `offCode` : distance to match + ZSTD_REP_MOVE (values <= ZSTD_REP_MOVE are repCodes).
- *  `mlBase` : matchLength - MINMATCH
- *  Allowed to overread literals up to litLimit.
+ *  Store a sequence (litlen, litPtr, offBase and matchLength) into seqStore_t.
+ *  @offBase : Users should employ macros REPCODE_TO_OFFBASE() and OFFSET_TO_OFFBASE().
+ *  @matchLength : must be >= MINMATCH
+ *  Allowed to over-read literals up to litLimit.
 */
-HINT_INLINE UNUSED_ATTR
-void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* literals, const BYTE* litLimit, U32 offCode, size_t mlBase)
+HINT_INLINE UNUSED_ATTR void
+ZSTD_storeSeq(seqStore_t* seqStorePtr,
+              size_t litLength, const BYTE* literals, const BYTE* litLimit,
+              U32 offBase,
+              size_t matchLength)
 {
     BYTE const* const litLimit_w = litLimit - WILDCOPY_OVERLENGTH;
     BYTE const* const litEnd = literals + litLength;
@@ -594,8 +606,8 @@ void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* litera
     static const BYTE* g_start = NULL;
     if (g_start==NULL) g_start = (const BYTE*)literals;  /* note : index only works for compression within a single segment */
     {   U32 const pos = (U32)((const BYTE*)literals - g_start);
-        DEBUGLOG(6, "Cpos%7u :%3u literals, match%4u bytes at offCode%7u",
-               pos, (U32)litLength, (U32)mlBase+MINMATCH, (U32)offCode);
+        DEBUGLOG(6, "Cpos%7u :%3u literals, match%4u bytes at offBase%7u",
+               pos, (U32)litLength, (U32)matchLength, (U32)offBase);
     }
 #endif
     assert((size_t)(seqStorePtr->sequences - seqStorePtr->sequencesStart) < seqStorePtr->maxNbSeq);
@@ -605,9 +617,9 @@ void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* litera
     assert(literals + litLength <= litLimit);
     if (litEnd <= litLimit_w) {
         /* Common case we can use wildcopy.
-	 * First copy 16 bytes, because literals are likely short.
-	 */
-        assert(WILDCOPY_OVERLENGTH >= 16);
+         * First copy 16 bytes, because literals are likely short.
+         */
+        ZSTD_STATIC_ASSERT(WILDCOPY_OVERLENGTH >= 16);
         ZSTD_copy16(seqStorePtr->lit, literals);
         if (litLength > 16) {
             ZSTD_wildcopy(seqStorePtr->lit+16, literals+16, (ptrdiff_t)litLength-16, ZSTD_no_overlap);
@@ -626,19 +638,59 @@ void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* litera
     seqStorePtr->sequences[0].litLength = (U16)litLength;
 
     /* match offset */
-    seqStorePtr->sequences[0].offset = offCode + 1;
+    seqStorePtr->sequences[0].offBase = offBase;
 
     /* match Length */
-    if (mlBase>0xFFFF) {
-        assert(seqStorePtr->longLengthType == ZSTD_llt_none); /* there can only be a single long length */
-        seqStorePtr->longLengthType = ZSTD_llt_matchLength;
-        seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
+    assert(matchLength >= MINMATCH);
+    {   size_t const mlBase = matchLength - MINMATCH;
+        if (mlBase>0xFFFF) {
+            assert(seqStorePtr->longLengthType == ZSTD_llt_none); /* there can only be a single long length */
+            seqStorePtr->longLengthType = ZSTD_llt_matchLength;
+            seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
+        }
+        seqStorePtr->sequences[0].mlBase = (U16)mlBase;
     }
-    seqStorePtr->sequences[0].matchLength = (U16)mlBase;
 
     seqStorePtr->sequences++;
 }
 
+/* ZSTD_updateRep() :
+ * updates in-place @rep (array of repeat offsets)
+ * @offBase : sum-type, using numeric representation of ZSTD_storeSeq()
+ */
+MEM_STATIC void
+ZSTD_updateRep(U32 rep[ZSTD_REP_NUM], U32 const offBase, U32 const ll0)
+{
+    if (OFFBASE_IS_OFFSET(offBase)) {  /* full offset */
+        rep[2] = rep[1];
+        rep[1] = rep[0];
+        rep[0] = OFFBASE_TO_OFFSET(offBase);
+    } else {   /* repcode */
+        U32 const repCode = OFFBASE_TO_REPCODE(offBase) - 1 + ll0;
+        if (repCode > 0) {  /* note : if repCode==0, no change */
+            U32 const currentOffset = (repCode==ZSTD_REP_NUM) ? (rep[0] - 1) : rep[repCode];
+            rep[2] = (repCode >= 2) ? rep[1] : rep[2];
+            rep[1] = rep[0];
+            rep[0] = currentOffset;
+        } else {   /* repCode == 0 */
+            /* nothing to do */
+        }
+    }
+}
+
+typedef struct repcodes_s {
+    U32 rep[3];
+} repcodes_t;
+
+MEM_STATIC repcodes_t
+ZSTD_newRep(U32 const rep[ZSTD_REP_NUM], U32 const offBase, U32 const ll0)
+{
+    repcodes_t newReps;
+    ZSTD_memcpy(&newReps, rep, sizeof(newReps));
+    ZSTD_updateRep(newReps.rep, offBase, ll0);
+    return newReps;
+}
+
 
 /*-*************************************
 *  Match length counter
@@ -651,11 +703,17 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
 #           if STATIC_BMI2
                 return _tzcnt_u64(val) >> 3;
 #           else
-                unsigned long r = 0;
-                return _BitScanForward64( &r, (U64)val ) ? (unsigned)(r >> 3) : 0;
+                if (val != 0) {
+                    unsigned long r;
+                    _BitScanForward64(&r, (U64)val);
+                    return (unsigned)(r >> 3);
+                } else {
+                    /* Should not reach this code path */
+                    __assume(0);
+                }
 #           endif
 #       elif defined(__GNUC__) && (__GNUC__ >= 4)
-            return (__builtin_ctzll((U64)val) >> 3);
+            return (unsigned)(__builtin_ctzll((U64)val) >> 3);
 #       else
             static const int DeBruijnBytePos[64] = { 0, 0, 0, 0, 0, 1, 1, 2,
                                                      0, 3, 1, 3, 1, 4, 2, 7,
@@ -669,10 +727,16 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
 #       endif
         } else { /* 32 bits */
 #       if defined(_MSC_VER)
-            unsigned long r=0;
-            return _BitScanForward( &r, (U32)val ) ? (unsigned)(r >> 3) : 0;
+            if (val != 0) {
+                unsigned long r;
+                _BitScanForward(&r, (U32)val);
+                return (unsigned)(r >> 3);
+            } else {
+                /* Should not reach this code path */
+                __assume(0);
+            }
 #       elif defined(__GNUC__) && (__GNUC__ >= 3)
-            return (__builtin_ctz((U32)val) >> 3);
+            return (unsigned)(__builtin_ctz((U32)val) >> 3);
 #       else
             static const int DeBruijnBytePos[32] = { 0, 0, 3, 0, 3, 1, 3, 0,
                                                      3, 2, 2, 1, 3, 2, 0, 1,
@@ -687,11 +751,17 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
 #           if STATIC_BMI2
 			    return _lzcnt_u64(val) >> 3;
 #           else
-			    unsigned long r = 0;
-			    return _BitScanReverse64(&r, (U64)val) ? (unsigned)(r >> 3) : 0;
+                if (val != 0) {
+                    unsigned long r;
+                    _BitScanReverse64(&r, (U64)val);
+                    return (unsigned)(r >> 3);
+                } else {
+                    /* Should not reach this code path */
+                    __assume(0);
+                }
 #           endif
 #       elif defined(__GNUC__) && (__GNUC__ >= 4)
-            return (__builtin_clzll(val) >> 3);
+            return (unsigned)(__builtin_clzll(val) >> 3);
 #       else
             unsigned r;
             const unsigned n32 = sizeof(size_t)*4;   /* calculate this way due to compiler complaining in 32-bits mode */
@@ -702,10 +772,16 @@ static unsigned ZSTD_NbCommonBytes (size_t val)
 #       endif
         } else { /* 32 bits */
 #       if defined(_MSC_VER)
-            unsigned long r = 0;
-            return _BitScanReverse( &r, (unsigned long)val ) ? (unsigned)(r >> 3) : 0;
+            if (val != 0) {
+                unsigned long r;
+                _BitScanReverse(&r, (unsigned long)val);
+                return (unsigned)(r >> 3);
+            } else {
+                /* Should not reach this code path */
+                __assume(0);
+            }
 #       elif defined(__GNUC__) && (__GNUC__ >= 3)
-            return (__builtin_clz((U32)val) >> 3);
+            return (unsigned)(__builtin_clz((U32)val) >> 3);
 #       else
             unsigned r;
             if (!(val>>16)) { r=2; val>>=8; } else { r=0; val>>=24; }
@@ -884,9 +960,9 @@ MEM_STATIC void ZSTD_window_clear(ZSTD_window_t* window)
 
 MEM_STATIC U32 ZSTD_window_isEmpty(ZSTD_window_t const window)
 {
-    return window.dictLimit == 1 &&
-           window.lowLimit == 1 &&
-           (window.nextSrc - window.base) == 1;
+    return window.dictLimit == ZSTD_WINDOW_START_INDEX &&
+           window.lowLimit == ZSTD_WINDOW_START_INDEX &&
+           (window.nextSrc - window.base) == ZSTD_WINDOW_START_INDEX;
 }
 
 /**
@@ -937,7 +1013,9 @@ MEM_STATIC U32 ZSTD_window_canOverflowCorrect(ZSTD_window_t const window,
 {
     U32 const cycleSize = 1u << cycleLog;
     U32 const curr = (U32)((BYTE const*)src - window.base);
-    U32 const minIndexToOverflowCorrect = cycleSize + MAX(maxDist, cycleSize);
+    U32 const minIndexToOverflowCorrect = cycleSize
+                                        + MAX(maxDist, cycleSize)
+                                        + ZSTD_WINDOW_START_INDEX;
 
     /* Adjust the min index to backoff the overflow correction frequency,
      * so we don't waste too much CPU in overflow correction. If this
@@ -1012,10 +1090,14 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
     U32 const cycleSize = 1u << cycleLog;
     U32 const cycleMask = cycleSize - 1;
     U32 const curr = (U32)((BYTE const*)src - window->base);
-    U32 const currentCycle0 = curr & cycleMask;
-    /* Exclude zero so that newCurrent - maxDist >= 1. */
-    U32 const currentCycle1 = currentCycle0 == 0 ? cycleSize : currentCycle0;
-    U32 const newCurrent = currentCycle1 + MAX(maxDist, cycleSize);
+    U32 const currentCycle = curr & cycleMask;
+    /* Ensure newCurrent - maxDist >= ZSTD_WINDOW_START_INDEX. */
+    U32 const currentCycleCorrection = currentCycle < ZSTD_WINDOW_START_INDEX
+                                     ? MAX(cycleSize, ZSTD_WINDOW_START_INDEX)
+                                     : 0;
+    U32 const newCurrent = currentCycle
+                         + currentCycleCorrection
+                         + MAX(maxDist, cycleSize);
     U32 const correction = curr - newCurrent;
     /* maxDist must be a power of two so that:
      *   (newCurrent & cycleMask) == (curr & cycleMask)
@@ -1031,14 +1113,20 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
 
     window->base += correction;
     window->dictBase += correction;
-    if (window->lowLimit <= correction) window->lowLimit = 1;
-    else window->lowLimit -= correction;
-    if (window->dictLimit <= correction) window->dictLimit = 1;
-    else window->dictLimit -= correction;
+    if (window->lowLimit < correction + ZSTD_WINDOW_START_INDEX) {
+        window->lowLimit = ZSTD_WINDOW_START_INDEX;
+    } else {
+        window->lowLimit -= correction;
+    }
+    if (window->dictLimit < correction + ZSTD_WINDOW_START_INDEX) {
+        window->dictLimit = ZSTD_WINDOW_START_INDEX;
+    } else {
+        window->dictLimit -= correction;
+    }
 
     /* Ensure we can still reference the full window. */
     assert(newCurrent >= maxDist);
-    assert(newCurrent - maxDist >= 1);
+    assert(newCurrent - maxDist >= ZSTD_WINDOW_START_INDEX);
     /* Ensure that lowLimit and dictLimit didn't underflow. */
     assert(window->lowLimit <= newCurrent);
     assert(window->dictLimit <= newCurrent);
@@ -1149,11 +1237,12 @@ ZSTD_checkDictValidity(const ZSTD_window_t* window,
 
 MEM_STATIC void ZSTD_window_init(ZSTD_window_t* window) {
     ZSTD_memset(window, 0, sizeof(*window));
-    window->base = (BYTE const*)"";
-    window->dictBase = (BYTE const*)"";
-    window->dictLimit = 1;    /* start from 1, so that 1st position is valid */
-    window->lowLimit = 1;     /* it ensures first and later CCtx usages compress the same */
-    window->nextSrc = window->base + 1;   /* see issue #1241 */
+    window->base = (BYTE const*)" ";
+    window->dictBase = (BYTE const*)" ";
+    ZSTD_STATIC_ASSERT(ZSTD_DUBT_UNSORTED_MARK < ZSTD_WINDOW_START_INDEX); /* Start above ZSTD_DUBT_UNSORTED_MARK */
+    window->dictLimit = ZSTD_WINDOW_START_INDEX;    /* start from >0, so that 1st position is valid */
+    window->lowLimit = ZSTD_WINDOW_START_INDEX;     /* it ensures first and later CCtx usages compress the same */
+    window->nextSrc = window->base + ZSTD_WINDOW_START_INDEX;   /* see issue #1241 */
     window->nbOverflowCorrections = 0;
 }
 
@@ -1206,15 +1295,15 @@ MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
  */
 MEM_STATIC U32 ZSTD_getLowestMatchIndex(const ZSTD_matchState_t* ms, U32 curr, unsigned windowLog)
 {
-    U32    const maxDistance = 1U << windowLog;
-    U32    const lowestValid = ms->window.lowLimit;
-    U32    const withinWindow = (curr - lowestValid > maxDistance) ? curr - maxDistance : lowestValid;
-    U32    const isDictionary = (ms->loadedDictEnd != 0);
+    U32 const maxDistance = 1U << windowLog;
+    U32 const lowestValid = ms->window.lowLimit;
+    U32 const withinWindow = (curr - lowestValid > maxDistance) ? curr - maxDistance : lowestValid;
+    U32 const isDictionary = (ms->loadedDictEnd != 0);
     /* When using a dictionary the entire dictionary is valid if a single byte of the dictionary
      * is within the window. We invalidate the dictionary (and set loadedDictEnd to 0) when it isn't
      * valid for the entire block. So this check is sufficient to find the lowest valid match index.
      */
-    U32    const matchLowest = isDictionary ? lowestValid : withinWindow;
+    U32 const matchLowest = isDictionary ? lowestValid : withinWindow;
     return matchLowest;
 }
 

lib/compress/zstd_compress_literals.c

@@ -13,6 +13,29 @@
  ***************************************/
 #include "zstd_compress_literals.h"
 
+
+/* **************************************************************
+*  Debug Traces
+****************************************************************/
+#if DEBUGLEVEL >= 2
+
+static size_t showHexa(const void* src, size_t srcSize)
+{
+    const BYTE* const ip = (const BYTE*)src;
+    size_t u;
+    for (u=0; u<srcSize; u++) {
+        RAWLOG(6, " %02X", ip[u]); (void)ip;
+    }
+    RAWLOG(6, " \n");
+    return srcSize;
+}
+
+#endif
+
+
+/* **************************************************************
+*  Literals compression - special cases
+****************************************************************/
 size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void* src, size_t srcSize)
 {
     BYTE* const ostart = (BYTE*)dst;
@@ -36,7 +59,7 @@ size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void* src,
     }
 
     ZSTD_memcpy(ostart + flSize, src, srcSize);
-    DEBUGLOG(5, "Raw literals: %u -> %u", (U32)srcSize, (U32)(srcSize + flSize));
+    DEBUGLOG(5, "Raw (uncompressed) literals: %u -> %u", (U32)srcSize, (U32)(srcSize + flSize));
     return srcSize + flSize;
 }
 
@@ -73,7 +96,8 @@ size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
                               void* dst, size_t dstCapacity,
                         const void* src, size_t srcSize,
                               void* entropyWorkspace, size_t entropyWorkspaceSize,
-                        const int bmi2)
+                        const int bmi2,
+                        unsigned suspectUncompressible)
 {
     size_t const minGain = ZSTD_minGain(srcSize, strategy);
     size_t const lhSize = 3 + (srcSize >= 1 KB) + (srcSize >= 16 KB);
@@ -85,6 +109,8 @@ size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
     DEBUGLOG(5,"ZSTD_compressLiterals (disableLiteralCompression=%i srcSize=%u)",
                 disableLiteralCompression, (U32)srcSize);
 
+    DEBUGLOG(6, "Completed literals listing (%zu bytes)", showHexa(src, srcSize));
+
     /* Prepare nextEntropy assuming reusing the existing table */
     ZSTD_memcpy(nextHuf, prevHuf, sizeof(*prevHuf));
 
@@ -99,17 +125,18 @@ size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
 
     RETURN_ERROR_IF(dstCapacity < lhSize+1, dstSize_tooSmall, "not enough space for compression");
     {   HUF_repeat repeat = prevHuf->repeatMode;
-        int const preferRepeat = strategy < ZSTD_lazy ? srcSize <= 1024 : 0;
+        int const preferRepeat = (strategy < ZSTD_lazy) ? srcSize <= 1024 : 0;
+        typedef size_t (*huf_compress_f)(void*, size_t, const void*, size_t, unsigned, unsigned, void*, size_t, HUF_CElt*, HUF_repeat*, int, int, unsigned);
+        huf_compress_f huf_compress;
         if (repeat == HUF_repeat_valid && lhSize == 3) singleStream = 1;
-        cLitSize = singleStream ?
-            HUF_compress1X_repeat(
-                ostart+lhSize, dstCapacity-lhSize, src, srcSize,
-                HUF_SYMBOLVALUE_MAX, HUF_TABLELOG_DEFAULT, entropyWorkspace, entropyWorkspaceSize,
-                (HUF_CElt*)nextHuf->CTable, &repeat, preferRepeat, bmi2) :
-            HUF_compress4X_repeat(
-                ostart+lhSize, dstCapacity-lhSize, src, srcSize,
-                HUF_SYMBOLVALUE_MAX, HUF_TABLELOG_DEFAULT, entropyWorkspace, entropyWorkspaceSize,
-                (HUF_CElt*)nextHuf->CTable, &repeat, preferRepeat, bmi2);
+        huf_compress = singleStream ? HUF_compress1X_repeat : HUF_compress4X_repeat;
+        cLitSize = huf_compress(ostart+lhSize, dstCapacity-lhSize,
+                                src, srcSize,
+                                HUF_SYMBOLVALUE_MAX, LitHufLog,
+                                entropyWorkspace, entropyWorkspaceSize,
+                                (HUF_CElt*)nextHuf->CTable,
+                                &repeat, preferRepeat,
+                                bmi2, suspectUncompressible);
         if (repeat != HUF_repeat_none) {
             /* reused the existing table */
             DEBUGLOG(5, "Reusing previous huffman table");
@@ -135,7 +162,7 @@ size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
     switch(lhSize)
     {
     case 3: /* 2 - 2 - 10 - 10 */
-        {   U32 const lhc = hType + ((!singleStream) << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<14);
+        {   U32 const lhc = hType + ((U32)(!singleStream) << 2) + ((U32)srcSize<<4) + ((U32)cLitSize<<14);
             MEM_writeLE24(ostart, lhc);
             break;
         }

lib/compress/zstd_compress_literals.h

@@ -18,12 +18,14 @@ size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void* src,
 
 size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, const void* src, size_t srcSize);
 
+/* If suspectUncompressible then some sampling checks will be run to potentially skip huffman coding */
 size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
                               ZSTD_hufCTables_t* nextHuf,
                               ZSTD_strategy strategy, int disableLiteralCompression,
                               void* dst, size_t dstCapacity,
                         const void* src, size_t srcSize,
                               void* entropyWorkspace, size_t entropyWorkspaceSize,
-                        const int bmi2);
+                        const int bmi2,
+                        unsigned suspectUncompressible);
 
 #endif /* ZSTD_COMPRESS_LITERALS_H */

lib/compress/zstd_compress_sequences.c

@@ -275,10 +275,11 @@ ZSTD_buildCTable(void* dst, size_t dstCapacity,
         assert(nbSeq_1 > 1);
         assert(entropyWorkspaceSize >= sizeof(ZSTD_BuildCTableWksp));
         (void)entropyWorkspaceSize;
-        FORWARD_IF_ERROR(FSE_normalizeCount(wksp->norm, tableLog, count, nbSeq_1, max, ZSTD_useLowProbCount(nbSeq_1)), "");
-        {   size_t const NCountSize = FSE_writeNCount(op, oend - op, wksp->norm, max, tableLog);   /* overflow protected */
+        FORWARD_IF_ERROR(FSE_normalizeCount(wksp->norm, tableLog, count, nbSeq_1, max, ZSTD_useLowProbCount(nbSeq_1)), "FSE_normalizeCount failed");
+        assert(oend >= op);
+        {   size_t const NCountSize = FSE_writeNCount(op, (size_t)(oend - op), wksp->norm, max, tableLog);   /* overflow protected */
             FORWARD_IF_ERROR(NCountSize, "FSE_writeNCount failed");
-            FORWARD_IF_ERROR(FSE_buildCTable_wksp(nextCTable, wksp->norm, max, tableLog, wksp->wksp, sizeof(wksp->wksp)), "");
+            FORWARD_IF_ERROR(FSE_buildCTable_wksp(nextCTable, wksp->norm, max, tableLog, wksp->wksp, sizeof(wksp->wksp)), "FSE_buildCTable_wksp failed");
             return NCountSize;
         }
     }
@@ -312,19 +313,19 @@ ZSTD_encodeSequences_body(
     FSE_initCState2(&stateLitLength,   CTable_LitLength,   llCodeTable[nbSeq-1]);
     BIT_addBits(&blockStream, sequences[nbSeq-1].litLength, LL_bits[llCodeTable[nbSeq-1]]);
     if (MEM_32bits()) BIT_flushBits(&blockStream);
-    BIT_addBits(&blockStream, sequences[nbSeq-1].matchLength, ML_bits[mlCodeTable[nbSeq-1]]);
+    BIT_addBits(&blockStream, sequences[nbSeq-1].mlBase, ML_bits[mlCodeTable[nbSeq-1]]);
     if (MEM_32bits()) BIT_flushBits(&blockStream);
     if (longOffsets) {
         U32 const ofBits = ofCodeTable[nbSeq-1];
         unsigned const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
         if (extraBits) {
-            BIT_addBits(&blockStream, sequences[nbSeq-1].offset, extraBits);
+            BIT_addBits(&blockStream, sequences[nbSeq-1].offBase, extraBits);
             BIT_flushBits(&blockStream);
         }
-        BIT_addBits(&blockStream, sequences[nbSeq-1].offset >> extraBits,
+        BIT_addBits(&blockStream, sequences[nbSeq-1].offBase >> extraBits,
                     ofBits - extraBits);
     } else {
-        BIT_addBits(&blockStream, sequences[nbSeq-1].offset, ofCodeTable[nbSeq-1]);
+        BIT_addBits(&blockStream, sequences[nbSeq-1].offBase, ofCodeTable[nbSeq-1]);
     }
     BIT_flushBits(&blockStream);
 
@@ -338,8 +339,8 @@ ZSTD_encodeSequences_body(
             U32  const mlBits = ML_bits[mlCode];
             DEBUGLOG(6, "encoding: litlen:%2u - matchlen:%2u - offCode:%7u",
                         (unsigned)sequences[n].litLength,
-                        (unsigned)sequences[n].matchLength + MINMATCH,
-                        (unsigned)sequences[n].offset);
+                        (unsigned)sequences[n].mlBase + MINMATCH,
+                        (unsigned)sequences[n].offBase);
                                                                             /* 32b*/  /* 64b*/
                                                                             /* (7)*/  /* (7)*/
             FSE_encodeSymbol(&blockStream, &stateOffsetBits, ofCode);       /* 15 */  /* 15 */
@@ -350,18 +351,18 @@ ZSTD_encodeSequences_body(
                 BIT_flushBits(&blockStream);                                /* (7)*/
             BIT_addBits(&blockStream, sequences[n].litLength, llBits);
             if (MEM_32bits() && ((llBits+mlBits)>24)) BIT_flushBits(&blockStream);
-            BIT_addBits(&blockStream, sequences[n].matchLength, mlBits);
+            BIT_addBits(&blockStream, sequences[n].mlBase, mlBits);
             if (MEM_32bits() || (ofBits+mlBits+llBits > 56)) BIT_flushBits(&blockStream);
             if (longOffsets) {
                 unsigned const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN-1);
                 if (extraBits) {
-                    BIT_addBits(&blockStream, sequences[n].offset, extraBits);
+                    BIT_addBits(&blockStream, sequences[n].offBase, extraBits);
                     BIT_flushBits(&blockStream);                            /* (7)*/
                 }
-                BIT_addBits(&blockStream, sequences[n].offset >> extraBits,
+                BIT_addBits(&blockStream, sequences[n].offBase >> extraBits,
                             ofBits - extraBits);                            /* 31 */
             } else {
-                BIT_addBits(&blockStream, sequences[n].offset, ofBits);     /* 31 */
+                BIT_addBits(&blockStream, sequences[n].offBase, ofBits);     /* 31 */
             }
             BIT_flushBits(&blockStream);                                    /* (7)*/
             DEBUGLOG(7, "remaining space : %i", (int)(blockStream.endPtr - blockStream.ptr));
@@ -398,7 +399,7 @@ ZSTD_encodeSequences_default(
 
 #if DYNAMIC_BMI2
 
-static TARGET_ATTRIBUTE("bmi2") size_t
+static BMI2_TARGET_ATTRIBUTE size_t
 ZSTD_encodeSequences_bmi2(
             void* dst, size_t dstCapacity,
             FSE_CTable const* CTable_MatchLength, BYTE const* mlCodeTable,

lib/compress/zstd_compress_superblock.c

@@ -38,11 +38,12 @@
  *  @return : compressed size of literals section of a sub-block
  *            Or 0 if it unable to compress.
  *            Or error code */
-static size_t ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable,
-                                    const ZSTD_hufCTablesMetadata_t* hufMetadata,
-                                    const BYTE* literals, size_t litSize,
-                                    void* dst, size_t dstSize,
-                                    const int bmi2, int writeEntropy, int* entropyWritten)
+static size_t
+ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable,
+                              const ZSTD_hufCTablesMetadata_t* hufMetadata,
+                              const BYTE* literals, size_t litSize,
+                              void* dst, size_t dstSize,
+                              const int bmi2, int writeEntropy, int* entropyWritten)
 {
     size_t const header = writeEntropy ? 200 : 0;
     size_t const lhSize = 3 + (litSize >= (1 KB - header)) + (litSize >= (16 KB - header));
@@ -126,12 +127,17 @@ static size_t ZSTD_compressSubBlock_literal(const HUF_CElt* hufTable,
     return op-ostart;
 }
 
-static size_t ZSTD_seqDecompressedSize(seqStore_t const* seqStore, const seqDef* sequences, size_t nbSeq, size_t litSize, int lastSequence) {
+static size_t
+ZSTD_seqDecompressedSize(seqStore_t const* seqStore,
+                   const seqDef* sequences, size_t nbSeq,
+                         size_t litSize, int lastSequence)
+{
     const seqDef* const sstart = sequences;
     const seqDef* const send = sequences + nbSeq;
     const seqDef* sp = sstart;
     size_t matchLengthSum = 0;
     size_t litLengthSum = 0;
+    (void)(litLengthSum); /* suppress unused variable warning on some environments */
     while (send-sp > 0) {
         ZSTD_sequenceLength const seqLen = ZSTD_getSequenceLength(seqStore, sp);
         litLengthSum += seqLen.litLength;
@@ -155,13 +161,14 @@ static size_t ZSTD_seqDecompressedSize(seqStore_t const* seqStore, const seqDef*
  *  @return : compressed size of sequences section of a sub-block
  *            Or 0 if it is unable to compress
  *            Or error code. */
-static size_t ZSTD_compressSubBlock_sequences(const ZSTD_fseCTables_t* fseTables,
-                                              const ZSTD_fseCTablesMetadata_t* fseMetadata,
-                                              const seqDef* sequences, size_t nbSeq,
-                                              const BYTE* llCode, const BYTE* mlCode, const BYTE* ofCode,
-                                              const ZSTD_CCtx_params* cctxParams,
-                                              void* dst, size_t dstCapacity,
-                                              const int bmi2, int writeEntropy, int* entropyWritten)
+static size_t
+ZSTD_compressSubBlock_sequences(const ZSTD_fseCTables_t* fseTables,
+                                const ZSTD_fseCTablesMetadata_t* fseMetadata,
+                                const seqDef* sequences, size_t nbSeq,
+                                const BYTE* llCode, const BYTE* mlCode, const BYTE* ofCode,
+                                const ZSTD_CCtx_params* cctxParams,
+                                void* dst, size_t dstCapacity,
+                                const int bmi2, int writeEntropy, int* entropyWritten)
 {
     const int longOffsets = cctxParams->cParams.windowLog > STREAM_ACCUMULATOR_MIN;
     BYTE* const ostart = (BYTE*)dst;
@@ -324,7 +331,7 @@ static size_t ZSTD_estimateSubBlockSize_literal(const BYTE* literals, size_t lit
 static size_t ZSTD_estimateSubBlockSize_symbolType(symbolEncodingType_e type,
                         const BYTE* codeTable, unsigned maxCode,
                         size_t nbSeq, const FSE_CTable* fseCTable,
-                        const U32* additionalBits,
+                        const U8* additionalBits,
                         short const* defaultNorm, U32 defaultNormLog, U32 defaultMax,
                         void* workspace, size_t wkspSize)
 {
@@ -474,7 +481,7 @@ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr,
         /* I think there is an optimization opportunity here.
          * Calling ZSTD_estimateSubBlockSize for every sequence can be wasteful
          * since it recalculates estimate from scratch.
-         * For example, it would recount literal distribution and symbol codes everytime.
+         * For example, it would recount literal distribution and symbol codes every time.
          */
         cBlockSizeEstimate = ZSTD_estimateSubBlockSize(lp, litSize, ofCodePtr, llCodePtr, mlCodePtr, seqCount,
                                                        &nextCBlock->entropy, entropyMetadata,
@@ -538,7 +545,7 @@ static size_t ZSTD_compressSubBlock_multi(const seqStore_t* seqStorePtr,
             repcodes_t rep;
             ZSTD_memcpy(&rep, prevCBlock->rep, sizeof(rep));
             for (seq = sstart; seq < sp; ++seq) {
-                rep = ZSTD_updateRep(rep.rep, seq->offset - 1, ZSTD_getSequenceLength(seqStorePtr, seq).litLength == 0);
+                ZSTD_updateRep(rep.rep, seq->offBase, ZSTD_getSequenceLength(seqStorePtr, seq).litLength == 0);
             }
             ZSTD_memcpy(nextCBlock->rep, &rep, sizeof(rep));
         }