Add extra space to match linux kernel

It is no longer necessary to get good performance, there is only a small
speed difference between -O2 and -O3, so just stick to the default of
-O2.

This also fixes the stack space usage on parisc. The compiler was buggy
for -O3 and used ~3KB of stack space for several functions. With -O2 the
problem is completely resolved, and stack space is back to a few hundred
bytes.

Additionally, we get a large code size win on gcc:

| Compiler | Before (Bytes) | After (Bytes) | Delta (Bytes) |
|----------|----------------|---------------|---------------|
| gcc-11   |         952754 |        738954 |       -213800 |
| clang-12 |         976290 |        938826 |        -37464 |

.github/workflows/generic-dev.yml

@@ -30,9 +30,6 @@ jobs:
 
   test:
     runs-on: ubuntu-latest
-    env:
-      DEVNULLRIGHTS: 1
-      READFROMBLOCKDEVICE: 1
     steps:
     - uses: actions/checkout@v2
     - name: make test
@@ -58,9 +55,11 @@ jobs:
         CC=gcc-7 CFLAGS=-Werror make -j all
         make clean
         LDFLAGS=-Wl,--no-undefined make -C lib libzstd-mt
+        make -C tests zbufftest-dll
 
     # candidate test (to check) : underlink test
     # LDFLAGS=-Wl,--no-undefined : will make the linker fail if dll is underlinked
+    # zbufftest-dll : test that a user program can link to multi-threaded libzstd without specifying -pthread
 
   gcc-8-asan-ubsan-testzstd:
     runs-on: ubuntu-latest
@@ -127,16 +126,6 @@ jobs:
         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:

.github/workflows/generic-release.yml

@@ -25,6 +25,14 @@ jobs:
         make test
         # make -c lib all (need to fix. not working right now)
 
+  zbuff:
+    runs-on: ubuntu-16.04
+    steps:
+    - uses: actions/checkout@v2
+    - name: zbuff test
+      run: |
+        make -C tests test-zbuff
+
   tsan:
     runs-on: ubuntu-latest
     steps:

.gitignore

@@ -50,5 +50,3 @@ googletest/
 *.code-workspace
 compile_commands.json
 .clangd
-perf.data
-perf.data.old

.travis.yml

@@ -124,8 +124,8 @@ matrix:
 
     # meson dedicated test
     - name: Xenial (Meson + clang)    # ~15mn
-      if: branch = travisTest
-      dist: bionic
+      if: branch = release
+      dist: xenial
       language: cpp
       compiler: clang
       install:

CHANGELOG

@@ -1,59 +1,3 @@
-v1.5.0  (May 11, 2021)
-api: Various functions promoted from experimental to stable API: (#2579-2581, @senhuang42)
-  `ZSTD_defaultCLevel()`
-  `ZSTD_getDictID_fromCDict()`
-api: Several experimental functions have been deprecated and will emit a compiler warning (#2582, @senhuang42)
-  `ZSTD_compress_advanced()`
-  `ZSTD_compress_usingCDict_advanced()`
-  `ZSTD_compressBegin_advanced()`
-  `ZSTD_compressBegin_usingCDict_advanced()`
-  `ZSTD_initCStream_srcSize()`
-  `ZSTD_initCStream_usingDict()`
-  `ZSTD_initCStream_usingCDict()`
-  `ZSTD_initCStream_advanced()`
-  `ZSTD_initCStream_usingCDict_advanced()`
-  `ZSTD_resetCStream()`
-api: ZSTDMT_NBWORKERS_MAX reduced to 64 for 32-bit environments (@Cyan4973)
-perf: Significant speed improvements for middle compression levels (#2494, @senhuang42 @terrelln)
-perf: Block splitter to improve compression ratio, enabled by default for high compression levels (#2447, @senhuang42)
-perf: Decompression loop refactor, speed improvements on `clang` and for `--long` modes (#2614 #2630, @Cyan4973)
-perf: Reduced stack usage during compression and decompression entropy stage (#2522 #2524, @terrelln)
-bug: Improve setting permissions of created files (#2525, @felixhandte)
-bug: Fix large dictionary non-determinism (#2607, @terrelln)
-bug: Fix non-determinism test failures on Linux i686 (#2606, @terrelln)
-bug: Fix various dedicated dictionary search bugs (#2540 #2586, @senhuang42 @felixhandte)
-bug: Ensure `ZSTD_estimateCCtxSize*() `monotonically increases with compression level (#2538, @senhuang42)
-bug: Fix --patch-from mode parameter bound bug with small files (#2637, @occivink)
-bug: Fix UBSAN error in decompression (#2625, @terrelln)
-bug: Fix superblock compression divide by zero bug (#2592, @senhuang42)
-bug: Make the number of physical CPU cores detection more robust (#2517, @PaulBone)
-doc: Improve `zdict.h` dictionary training API documentation (#2622, @terrelln)
-doc: Note that public `ZSTD_free*()` functions accept NULL pointers (#2521, @animalize)
-doc: Add style guide docs for open source contributors (#2626, @Cyan4973)
-tests: Better regression test coverage for different dictionary modes (#2559, @senhuang42)
-tests: Better test coverage of index reduction (#2603, @terrelln)
-tests: OSS-Fuzz coverage for seekable format (#2617, @senhuang42)
-tests: Test coverage for ZSTD threadpool API (#2604, @senhuang42)
-build: Dynamic library built multithreaded by default (#2584, @senhuang42)
-build: Move  `zstd_errors.h`  and  `zdict.h`  to  `lib/`  root (#2597, @terrelln)
-build: Allow `ZSTDMT_JOBSIZE_MIN` to be configured at compile-time, reduce default to 512KB (#2611, @Cyan4973)
-build: Single file library build script moved to `build/` directory (#2618, @felixhandte)
-build: `ZBUFF_*()` is no longer built by default (#2583, @senhuang42)
-build: Fixed Meson build (#2548, @SupervisedThinking @kloczek)
-build: Fix excessive compiler warnings with clang-cl and CMake (#2600, @nickhutchinson)
-build: Detect presence of `md5` on Darwin (#2609, @felixhandte)
-build: Avoid SIGBUS on armv6 (#2633, @bmwiedmann)
-cli: `--progress` flag added to always display progress bar (#2595, @senhuang42)
-cli: Allow reading from block devices with `--force` (#2613, @felixhandte)
-cli: Fix CLI filesize display bug (#2550, @Cyan4973)
-cli: Fix windows CLI `--filelist` end-of-line bug (#2620, @Cyan4973)
-contrib: Various fixes for linux kernel patch (#2539, @terrelln)
-contrib: Seekable format - Decompression hanging edge case fix (#2516, @senhuang42)
-contrib: Seekable format - New seek table-only API  (#2113 #2518, @mdittmer @Cyan4973)
-contrib: Seekable format - Fix seek table descriptor check when loading (#2534, @foxeng)
-contrib: Seekable format - Decompression fix for large offsets, (#2594, @azat)
-misc: Automatically published release tarballs available on Github (#2535, @felixhandte)
-
 v1.4.9  (Mar 1, 2021)
 bug: Use `umask()` to Constrain Created File Permissions (#2495, @felixhandte)
 bug: Make Simple Single-Pass Functions Ignore Advanced Parameters (#2498, @terrelln)

CONTRIBUTING.md

@@ -399,105 +399,7 @@ disclosure of security bugs. In those cases, please go through the process
 outlined on that page and do not file a public issue.
 
 ## Coding Style
-It's a pretty long topic, which is difficult to summarize in a single paragraph.
-As a rule of thumbs, try to imitate the coding style of
-similar lines of codes around your contribution.
-The following is a non-exhaustive list of rules employed in zstd code base:
-
-### C90
-This code base is following strict C90 standard,
-with 2 extensions : 64-bit `long long` types, and variadic macros.
-This rule is applied strictly to code within `lib/` and `programs/`.
-Sub-project in `contrib/` are allowed to use other conventions.
-
-### C++ direct compatibility : symbol mangling
-All public symbol declarations must be wrapped in `extern “C” { … }`,
-so that this project can be compiled as C++98 code,
-and linked into C++ applications.
-
-### Minimal Frugal
-This design requirement is fundamental to preserve the portability of the code base.
-#### Dependencies
-- Reduce dependencies to the minimum possible level.
-  Any dependency should be considered “bad” by default,
-  and only tolerated because it provides a service in a better way than can be achieved locally.
-  The only external dependencies this repository tolerates are
-  standard C libraries, and in rare cases, system level headers.
-- Within `lib/`, this policy is even more drastic.
-  The only external dependencies allowed are `<assert.h>`, `<stdlib.h>`, `<string.h>`,
-  and even then, not directly.
-  In particular, no function shall ever allocate on heap directly,
-  and must use instead `ZSTD_malloc()` and equivalent.
-  Other accepted non-symbol headers are `<stddef.h>` and `<limits.h>`.
-- Within the project, there is a strict hierarchy of dependencies that must be respected.
-  `programs/` is allowed to depend on `lib/`, but only its public API.
-  Within `lib/`, `lib/common` doesn't depend on any other directory.
-  `lib/compress` and `lib/decompress` shall not depend on each other.
-  `lib/dictBuilder` can depend on `lib/common` and `lib/compress`, but not `lib/decompress`.
-#### Resources
-- Functions in `lib/` must use very little stack space,
-  several dozens of bytes max.
-  Everything larger must use the heap allocator,
-  or require a scratch buffer to be emplaced manually.
-
-### Naming
-* All public symbols are prefixed with `ZSTD_`
-  + private symbols, with a scope limited to their own unit, are free of this restriction.
-    However, since `libzstd` source code can be amalgamated,
-    each symbol name must attempt to be (and remain) unique.
-    Avoid too generic names that could become ground for future collisions.
-    This generally implies usage of some form of prefix.
-* For symbols (functions and variables), naming convention is `PREFIX_camelCase`.
-  + In some advanced cases, one can also find :
-    - `PREFIX_prefix2_camelCase`
-    - `PREFIX_camelCase_extendedQualifier`
-* Multi-words names generally consist of an action followed by object:
-  - for example : `ZSTD_createCCtx()`
-* Prefer positive actions
-  - `goBackward` rather than `notGoForward`
-* Type names (`struct`, etc.) follow similar convention,
-  except that they are allowed and even invited to start by an Uppercase letter.
-  Example : `ZSTD_CCtx`, `ZSTD_CDict`
-* Macro names are all Capital letters.
-  The same composition rules (`PREFIX_NAME_QUALIFIER`) apply.
-* File names are all lowercase letters.
-  The convention is `snake_case`.
-  File names **must** be unique across the entire code base,
-  even when they stand in clearly separated directories.
-
-### Qualifiers
-* This code base is `const` friendly, if not `const` fanatical.
-  Any variable that can be `const` (aka. read-only) **must** be `const`.
-  Any pointer which content will not be modified must be `const`.
-  This property is then controlled at compiler level.
-  `const` variables are an important signal to readers that this variable isn’t modified.
-  Conversely, non-const variables are a signal to readers to watch out for modifications later on in the function.
-* If a function must be inlined, mention it explicitly,
-  using project's own portable macros, such as `FORCE_INLINE_ATTR`,
-  defined in `lib/common/compiler.h`.
-
-### Debugging
-* **Assertions** are welcome, and should be used very liberally,
-  to control any condition the code expects for its correct execution.
-  These assertion checks will be run in debug builds, and disabled in production.
-* For traces, this project provides its own debug macros,
-  in particular `DEBUGLOG(level, ...)`, defined in `lib/common/debug.h`.
-
-### Code documentation
-* Avoid code documentation that merely repeats what the code is already stating.
-  Whenever applicable, prefer employing the code as the primary way to convey explanations.
-  Example 1 : `int nbTokens = n;` instead of `int i = n; /* i is a nb of tokens *./`.
-  Example 2 : `assert(size > 0);` instead of `/* here, size should be positive */`.
-* At declaration level, the documentation explains how to use the function or variable
-  and when applicable why it's needed, of the scenarios where it can be useful.
-* At implementation level, the documentation explains the general outline of the algorithm employed,
-  and when applicable why this specific choice was preferred.
-
-### General layout
 * 4 spaces for indentation rather than tabs
-* Code documentation shall directly precede function declaration or implementation
-* Function implementations and its code documentation should be preceded and followed by an empty line
-
 
 ## License
 By contributing to Zstandard, you agree that your contributions will be licensed

Makefile

@@ -57,8 +57,8 @@ all32:
 	$(MAKE) -C $(PRGDIR) zstd32
 	$(MAKE) -C $(TESTDIR) all32
 
-.PHONY: lib lib-release lib-mt lib-nomt
-lib lib-release lib-mt lib-nomt:
+.PHONY: lib lib-release
+lib lib-release :
 	$(Q)$(MAKE) -C $(ZSTDDIR) $@
 
 .PHONY: zstd zstd-release
@@ -122,8 +122,8 @@ contrib: lib
 	$(MAKE) -C contrib/seekable_format/examples all
 	$(MAKE) -C contrib/seekable_format/tests test
 	$(MAKE) -C contrib/largeNbDicts all
-	cd build/single_file_libs/ ; ./build_decoder_test.sh
-	cd build/single_file_libs/ ; ./build_library_test.sh
+	cd contrib/single_file_libs/ ; ./build_decoder_test.sh
+	cd contrib/single_file_libs/ ; ./build_library_test.sh
 
 .PHONY: cleanTabs
 cleanTabs:
@@ -151,6 +151,7 @@ clean:
 ifneq (,$(filter $(shell uname),Linux Darwin GNU/kFreeBSD GNU OpenBSD FreeBSD DragonFly NetBSD MSYS_NT Haiku))
 
 HOST_OS = POSIX
+CMAKE_PARAMS = -DZSTD_BUILD_CONTRIB:BOOL=ON -DZSTD_BUILD_STATIC:BOOL=ON -DZSTD_BUILD_TESTS:BOOL=ON -DZSTD_ZLIB_SUPPORT:BOOL=ON -DZSTD_LZMA_SUPPORT:BOOL=ON -DCMAKE_BUILD_TYPE=Release
 
 HAVE_COLORNEVER = $(shell echo a | egrep --color=never a > /dev/null 2> /dev/null && echo 1 || echo 0)
 EGREP_OPTIONS ?=
@@ -178,7 +179,7 @@ list:
 	    done \
 	} | column -t -s $$'\t'
 
-.PHONY: install armtest usan asan uasan msan asan32
+.PHONY: install armtest usan asan uasan
 install:
 	$(Q)$(MAKE) -C $(ZSTDDIR) $@
 	$(Q)$(MAKE) -C $(PRGDIR) $@
@@ -192,19 +193,22 @@ uninstall:
 travis-install:
 	$(MAKE) install PREFIX=~/install_test_dir
 
-.PHONY: gcc5build gcc6build gcc7build clangbuild m32build armbuild aarch64build ppcbuild ppc64build
+.PHONY: gcc5build
 gcc5build: clean
 	gcc-5 -v
 	CC=gcc-5 $(MAKE) all MOREFLAGS="-Werror"
 
+.PHONY: gcc6build
 gcc6build: clean
 	gcc-6 -v
 	CC=gcc-6 $(MAKE) all MOREFLAGS="-Werror"
 
+.PHONY: gcc7build
 gcc7build: clean
 	gcc-7 -v
 	CC=gcc-7 $(MAKE) all MOREFLAGS="-Werror"
 
+.PHONY: clangbuild
 clangbuild: clean
 	clang -v
 	CXX=clang++ CC=clang CFLAGS="-Werror -Wconversion -Wno-sign-conversion -Wdocumentation" $(MAKE) all
@@ -225,7 +229,6 @@ ppcbuild: clean
 ppc64build: clean
 	CC=powerpc-linux-gnu-gcc CFLAGS="-m64 -Werror" $(MAKE) -j allzstd
 
-.PHONY: armfuzz aarch64fuzz ppcfuzz ppc64fuzz
 armfuzz: clean
 	CC=arm-linux-gnueabi-gcc QEMU_SYS=qemu-arm-static MOREFLAGS="-static" FUZZER_FLAGS=--no-big-tests $(MAKE) -C $(TESTDIR) fuzztest
 
@@ -239,7 +242,7 @@ ppcfuzz: clean
 ppc64fuzz: clean
 	CC=powerpc-linux-gnu-gcc QEMU_SYS=qemu-ppc64-static MOREFLAGS="-m64 -static" FUZZER_FLAGS=--no-big-tests $(MAKE) -C $(TESTDIR) fuzztest
 
-.PHONY: cxxtest gcc5test gcc6test armtest aarch64test ppctest ppc64test
+.PHONY: cxxtest
 cxxtest: CXXFLAGS += -Wall -Wextra -Wundef -Wshadow -Wcast-align -Werror
 cxxtest: clean
 	$(MAKE) -C $(PRGDIR) all CC="$(CXX) -Wno-deprecated" CFLAGS="$(CXXFLAGS)"   # adding -Wno-deprecated to avoid clang++ warning on dealing with C files directly
@@ -268,7 +271,6 @@ ppc64test: clean
 	$(MAKE) -C $(TESTDIR) datagen   # use native, faster
 	$(MAKE) -C $(TESTDIR) test CC=powerpc-linux-gnu-gcc QEMU_SYS=qemu-ppc64-static ZSTDRTTEST= MOREFLAGS="-m64 -static" FUZZER_FLAGS=--no-big-tests
 
-.PHONY: arm-ppc-compilation
 arm-ppc-compilation:
 	$(MAKE) -C $(PRGDIR) clean zstd CC=arm-linux-gnueabi-gcc QEMU_SYS=qemu-arm-static ZSTDRTTEST= MOREFLAGS="-Werror -static"
 	$(MAKE) -C $(PRGDIR) clean zstd CC=aarch64-linux-gnu-gcc QEMU_SYS=qemu-aarch64-static ZSTDRTTEST= MOREFLAGS="-Werror -static"
@@ -286,6 +288,7 @@ msanregressiontest:
 
 # run UBsan with -fsanitize-recover=pointer-overflow
 # this only works with recent compilers such as gcc 8+
+
 usan: clean
 	$(MAKE) test CC=clang MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize-recover=pointer-overflow -fsanitize=undefined -Werror"
 
@@ -313,16 +316,13 @@ uasan-%: clean
 tsan-%: clean
 	LDFLAGS=-fuse-ld=gold MOREFLAGS="-g -fno-sanitize-recover=all -fsanitize=thread -Werror" $(MAKE) -C $(TESTDIR) $* FUZZER_FLAGS=--no-big-tests
 
-.PHONY: apt-install
 apt-install:
 	sudo apt-get -yq --no-install-suggests --no-install-recommends --force-yes install $(APT_PACKAGES)
 
-.PHONY: apt-add-repo
 apt-add-repo:
 	sudo add-apt-repository -y ppa:ubuntu-toolchain-r/test
 	sudo apt-get update -y -qq
 
-.PHONY: ppcinstall arminstall valgrindinstall libc6install gcc6install gcc7install gcc8install gpp6install clang38install lz4install
 ppcinstall:
 	APT_PACKAGES="qemu-system-ppc qemu-user-static gcc-powerpc-linux-gnu" $(MAKE) apt-install
 
@@ -357,18 +357,16 @@ lz4install:
 endif
 
 
-CMAKE_PARAMS = -DZSTD_BUILD_CONTRIB:BOOL=ON -DZSTD_BUILD_STATIC:BOOL=ON -DZSTD_BUILD_TESTS:BOOL=ON -DZSTD_ZLIB_SUPPORT:BOOL=ON -DZSTD_LZMA_SUPPORT:BOOL=ON -DCMAKE_BUILD_TYPE=Release
-
 ifneq (,$(filter MSYS%,$(shell uname)))
 HOST_OS = MSYS
 CMAKE_PARAMS = -G"MSYS Makefiles" -DCMAKE_BUILD_TYPE=Debug -DZSTD_MULTITHREAD_SUPPORT:BOOL=OFF -DZSTD_BUILD_STATIC:BOOL=ON -DZSTD_BUILD_TESTS:BOOL=ON
 endif
 
+
 #------------------------------------------------------------------------
 # target specific tests
 #------------------------------------------------------------------------
 ifneq (,$(filter $(HOST_OS),MSYS POSIX))
-.PHONY: cmakebuild c89build gnu90build c99build gnu99build c11build bmix64build bmix32build bmi32build staticAnalyze
 cmakebuild:
 	cmake --version
 	$(RM) -r $(BUILDIR)/cmake/build

TESTING.md

@@ -40,4 +40,5 @@ They consist of the following tests:
 - Versions test (ensuring `zstd` can decode files from all previous versions)
 - `pzstd` with asan and tsan, as well as in 32-bits mode
 - Testing `zstd` with legacy mode off
+- Testing `zbuff` (old streaming API)
 - Entire test suite and make install on macOS

appveyor.yml

@@ -52,15 +52,6 @@
       PLATFORM: "Win32"
       CONFIGURATION: "Release"
 
-    - COMPILER: "clang-cl"
-      HOST:     "cmake-visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Release"
-      CMAKE_GENERATOR: "Visual Studio 15 2017"
-      CMAKE_GENERATOR_PLATFORM: "x64"
-      CMAKE_GENERATOR_TOOLSET: "LLVM"
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2017"
-
   install:
   - ECHO Installing %COMPILER% %PLATFORM% %CONFIGURATION%
   - SET PATH_ORIGINAL=%PATH%
@@ -163,15 +154,6 @@
       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% &&
-      PUSHD build\cmake &&
-      cmake -DBUILD_TESTING=ON . &&
-      cmake --build . --config %CONFIGURATION% -j4 &&
-      POPD &&
-      ECHO ***
-    )
 
   test_script:
   - ECHO Testing %COMPILER% %PLATFORM% %CONFIGURATION%
@@ -241,21 +223,13 @@
       PLATFORM: "Win32"
       CONFIGURATION: "Release"
 
-    - COMPILER: "clang-cl"
-      HOST:     "cmake-visual"
-      PLATFORM: "x64"
-      CONFIGURATION: "Release"
-      CMAKE_GENERATOR: "Visual Studio 15 2017"
-      CMAKE_GENERATOR_PLATFORM: "x64"
-      CMAKE_GENERATOR_TOOLSET: "LLVM"
-      APPVEYOR_BUILD_WORKER_IMAGE: "Visual Studio 2017"
-
   install:
   - ECHO Installing %COMPILER% %PLATFORM% %CONFIGURATION%
   - SET PATH_ORIGINAL=%PATH%
   - if [%HOST%]==[cygwin] (
       ECHO Installing Cygwin Packages &&
       C:\cygwin64\setup-x86_64.exe -qnNdO -R "C:\cygwin64" -g -P ^
+        gcc-g++,^
         gcc,^
         cmake,^
         make
@@ -278,8 +252,8 @@
       C:\cygwin64\bin\bash --login -c "
         set -e;
         cd build/cmake;
-        CFLAGS='-Werror' cmake -G 'Unix Makefiles' -DCMAKE_BUILD_TYPE=Debug -DZSTD_BUILD_TESTS:BOOL=ON -DZSTD_FUZZER_FLAGS=-T20s -DZSTD_ZSTREAM_FLAGS=-T20s -DZSTD_FULLBENCH_FLAGS=-i0 .;
-        make VERBOSE=1 -j;
+        CFLAGS='-Werror' cmake -G 'Unix Makefiles' -DCMAKE_BUILD_TYPE=Debug -DZSTD_BUILD_TESTS:BOOL=ON -DZSTD_FUZZER_FLAGS=-T30s -DZSTD_ZSTREAM_FLAGS=-T30s .;
+        make -j4;
         ctest -V -L Medium;
       "
     )
@@ -307,15 +281,6 @@
       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% &&
-      PUSHD build\cmake &&
-      cmake -DBUILD_TESTING=ON . &&
-      cmake --build . --config %CONFIGURATION% -j4 &&
-      POPD &&
-      ECHO ***
-    )
 
 
   test_script:

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"
@@ -463,7 +463,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File

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"
@@ -483,7 +483,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File
@@ -511,7 +511,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File

build/VS2008/zstd/zstd.vcproj

@@ -559,7 +559,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File
@@ -575,7 +575,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File

build/VS2008/zstdlib/zstdlib.vcproj

@@ -495,7 +495,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File
@@ -523,7 +523,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File

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>
@@ -190,7 +190,7 @@
     <ClInclude Include="..\..\..\lib\zstd.h" />
     <ClInclude Include="..\..\..\lib\common\fse.h" />
     <ClInclude Include="..\..\..\lib\common\huf.h" />
-    <ClInclude Include="..\..\..\lib\zstd_errors.h" />
+    <ClInclude Include="..\..\..\lib\common\zstd_errors.h" />
     <ClInclude Include="..\..\..\lib\common\zstd_internal.h" />
     <ClInclude Include="..\..\..\lib\common\pool.h" />
     <ClInclude Include="..\..\..\lib\common\threading.h" />

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>
@@ -196,7 +196,7 @@
     <ClInclude Include="..\..\..\lib\common\huf.h" />
     <ClInclude Include="..\..\..\lib\common\xxhash.h" />
     <ClInclude Include="..\..\..\lib\common\zstd_internal.h" />
-    <ClInclude Include="..\..\..\lib\zstd_errors.h" />
+    <ClInclude Include="..\..\..\lib\common\zstd_errors.h" />
     <ClInclude Include="..\..\..\lib\zstd.h" />
     <ClInclude Include="..\..\..\lib\compress\zstd_compress.h" />
     <ClInclude Include="..\..\..\lib\compress\zstd_compress_literals.h" />
@@ -211,7 +211,7 @@
     <ClInclude Include="..\..\..\lib\compress\zstdmt_compress.h" />
     <ClInclude Include="..\..\..\lib\decompress\zstd_ddict.h" />
     <ClInclude Include="..\..\..\lib\dictBuilder\divsufsort.h" />
-    <ClInclude Include="..\..\..\lib\zdict.h" />
+    <ClInclude Include="..\..\..\lib\dictBuilder\zdict.h" />
     <ClInclude Include="..\..\..\lib\dictBuilder\cover.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_legacy.h" />
     <ClInclude Include="..\..\..\programs\datagen.h" />

build/VS2010/libzstd-dll/libzstd-dll.vcxproj

@@ -44,6 +44,9 @@
     <ClCompile Include="..\..\..\lib\decompress\zstd_decompress.c" />
     <ClCompile Include="..\..\..\lib\decompress\zstd_decompress_block.c" />
     <ClCompile Include="..\..\..\lib\decompress\zstd_ddict.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_common.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_compress.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_decompress.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\cover.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\fastcover.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\divsufsort.c" />
@@ -61,11 +64,12 @@
     <ClInclude Include="..\..\..\lib\common\threading.h" />
     <ClInclude Include="..\..\..\lib\common\bitstream.h" />
     <ClInclude Include="..\..\..\lib\common\error_private.h" />
-    <ClInclude Include="..\..\..\lib\zstd_errors.h" />
+    <ClInclude Include="..\..\..\lib\common\zstd_errors.h" />
     <ClInclude Include="..\..\..\lib\common\mem.h" />
     <ClInclude Include="..\..\..\lib\common\fse.h" />
     <ClInclude Include="..\..\..\lib\common\huf.h" />
     <ClInclude Include="..\..\..\lib\common\xxhash.h" />
+    <ClInclude Include="..\..\..\lib\deprecated\zbuff.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_legacy.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_v01.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_v02.h" />

build/VS2010/libzstd/libzstd.vcxproj

@@ -44,6 +44,9 @@
     <ClCompile Include="..\..\..\lib\decompress\zstd_decompress.c" />
     <ClCompile Include="..\..\..\lib\decompress\zstd_decompress_block.c" />
     <ClCompile Include="..\..\..\lib\decompress\zstd_ddict.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_common.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_compress.c" />
+    <ClCompile Include="..\..\..\lib\deprecated\zbuff_decompress.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\cover.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\fastcover.c" />
     <ClCompile Include="..\..\..\lib\dictBuilder\divsufsort.c" />
@@ -61,11 +64,12 @@
     <ClInclude Include="..\..\..\lib\common\threading.h" />
     <ClInclude Include="..\..\..\lib\common\bitstream.h" />
     <ClInclude Include="..\..\..\lib\common\error_private.h" />
-    <ClInclude Include="..\..\..\lib\zstd_errors.h" />
+    <ClInclude Include="..\..\..\lib\common\zstd_errors.h" />
     <ClInclude Include="..\..\..\lib\common\mem.h" />
     <ClInclude Include="..\..\..\lib\common\fse.h" />
     <ClInclude Include="..\..\..\lib\common\huf.h" />
     <ClInclude Include="..\..\..\lib\common\xxhash.h" />
+    <ClInclude Include="..\..\..\lib\deprecated\zbuff.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_legacy.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_v01.h" />
     <ClInclude Include="..\..\..\lib\legacy\zstd_v02.h" />

build/VS2010/zstd/zstd.vcxproj

@@ -70,14 +70,14 @@
     <ClInclude Include="..\..\..\lib\common\threading.h" />
     <ClInclude Include="..\..\..\lib\common\xxhash.h" />
     <ClInclude Include="..\..\..\lib\compress\zstdmt_compress.h" />
-    <ClInclude Include="..\..\..\lib\zdict.h" />
+    <ClInclude Include="..\..\..\lib\dictBuilder\zdict.h" />
     <ClInclude Include="..\..\..\lib\dictBuilder\cover.h" />
     <ClInclude Include="..\..\..\lib\dictBuilder\divsufsort.h" />
     <ClInclude Include="..\..\..\lib\common\fse.h" />
     <ClInclude Include="..\..\..\lib\common\huf.h" />
     <ClInclude Include="..\..\..\lib\zstd.h" />
     <ClInclude Include="..\..\..\lib\common\zstd_internal.h" />
-    <ClInclude Include="..\..\..\lib\zstd_errors.h" />
+    <ClInclude Include="..\..\..\lib\common\zstd_errors.h" />
     <ClInclude Include="..\..\..\lib\compress\zstd_compress.h" />
     <ClInclude Include="..\..\..\lib\compress\zstd_compress_literals.h" />
     <ClInclude Include="..\..\..\lib\compress\zstd_compress_sequences.h" />

build/cmake/CMakeModules/AddZstdCompilationFlags.cmake

@@ -26,12 +26,7 @@ macro(ADD_ZSTD_COMPILATION_FLAGS)
         EnableCompilerFlag("-std=c++11" false true)
         #Set c99 by default
         EnableCompilerFlag("-std=c99" true false)
-        if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND MSVC)
-            # clang-cl normally maps -Wall to -Weverything.
-            EnableCompilerFlag("/clang:-Wall" true true)
-        else ()
-            EnableCompilerFlag("-Wall" true true)
-        endif ()
+        EnableCompilerFlag("-Wall" true true)
         EnableCompilerFlag("-Wextra" true true)
         EnableCompilerFlag("-Wundef" true true)
         EnableCompilerFlag("-Wshadow" true true)

build/cmake/lib/CMakeLists.txt

@@ -24,24 +24,28 @@ file(GLOB CommonSources ${LIBRARY_DIR}/common/*.c)
 file(GLOB CompressSources ${LIBRARY_DIR}/compress/*.c)
 file(GLOB DecompressSources ${LIBRARY_DIR}/decompress/*.c)
 file(GLOB DictBuilderSources ${LIBRARY_DIR}/dictBuilder/*.c)
+file(GLOB DeprecatedSources ${LIBRARY_DIR}/deprecated/*.c)
 
 set(Sources
         ${CommonSources}
         ${CompressSources}
         ${DecompressSources}
-        ${DictBuilderSources})
+        ${DictBuilderSources}
+        ${DeprecatedSources})
 
 file(GLOB CommonHeaders ${LIBRARY_DIR}/common/*.h)
 file(GLOB CompressHeaders ${LIBRARY_DIR}/compress/*.h)
 file(GLOB DecompressHeaders ${LIBRARY_DIR}/decompress/*.h)
 file(GLOB DictBuilderHeaders ${LIBRARY_DIR}/dictBuilder/*.h)
+file(GLOB DeprecatedHeaders ${LIBRARY_DIR}/deprecated/*.h)
 
 set(Headers
         ${LIBRARY_DIR}/zstd.h
         ${CommonHeaders}
         ${CompressHeaders}
         ${DecompressHeaders}
-        ${DictBuilderHeaders})
+        ${DictBuilderHeaders}
+        ${DeprecatedHeaders})
 
 if (ZSTD_LEGACY_SUPPORT)
     set(LIBRARY_LEGACY_DIR ${LIBRARY_DIR}/legacy)
@@ -158,8 +162,8 @@ endif ()
 # install target
 install(FILES
     "${LIBRARY_DIR}/zstd.h"
-    "${LIBRARY_DIR}/zdict.h"
-    "${LIBRARY_DIR}/zstd_errors.h"
+    "${LIBRARY_DIR}/dictBuilder/zdict.h"
+    "${LIBRARY_DIR}/common/zstd_errors.h"
     DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
 
 install(TARGETS ${library_targets}

build/cmake/tests/.gitignore

@@ -3,4 +3,5 @@ datagen
 fullbench
 fuzzer
 paramgrill
+zbufftest
 

build/cmake/tests/CMakeLists.txt

@@ -57,15 +57,13 @@ 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")
 target_link_libraries(fullbench libzstd_static)
-add_test(NAME fullbench COMMAND fullbench ${ZSTD_FULLBENCH_FLAGS})
+add_test(NAME fullbench COMMAND fullbench)
 
 #
 # fuzzer
 #
 add_executable(fuzzer ${PROGRAMS_DIR}/datagen.c ${PROGRAMS_DIR}/util.c ${PROGRAMS_DIR}/timefn.c ${TESTS_DIR}/fuzzer.c)
-set_property(TARGET fuzzer APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_DISABLE_DEPRECATE_WARNINGS")
 target_link_libraries(fuzzer libzstd_static)
 AddTestFlagsOption(ZSTD_FUZZER_FLAGS "$ENV{FUZZERTEST} $ENV{FUZZER_FLAGS}"
     "Semicolon-separated list of flags to pass to the fuzzer test (see `fuzzer -h` for usage)")
@@ -78,7 +76,6 @@ 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 ${TESTS_DIR}/zstreamtest.c)
-set_property(TARGET zstreamtest APPEND PROPERTY COMPILE_DEFINITIONS "ZSTD_DISABLE_DEPRECATE_WARNINGS")
 target_link_libraries(zstreamtest libzstd_static)
 AddTestFlagsOption(ZSTD_ZSTREAM_FLAGS "$ENV{ZSTREAM_TESTTIME} $ENV{FUZZER_FLAGS}"
     "Semicolon-separated list of flags to pass to the zstreamtest test (see `zstreamtest -h` for usage)")

build/meson/lib/meson.build

@@ -14,13 +14,15 @@ libzstd_includes = [include_directories(join_paths(zstd_rootdir,'lib'),
   join_paths(zstd_rootdir, 'lib/common'),
   join_paths(zstd_rootdir, 'lib/compress'),
   join_paths(zstd_rootdir, 'lib/decompress'),
-  join_paths(zstd_rootdir, 'lib/dictBuilder'))]
+  join_paths(zstd_rootdir, 'lib/dictBuilder'),
+  join_paths(zstd_rootdir, 'lib/deprecated'))]
 
 libzstd_sources = [join_paths(zstd_rootdir, 'lib/common/entropy_common.c'),
   join_paths(zstd_rootdir, 'lib/common/fse_decompress.c'),
   join_paths(zstd_rootdir, 'lib/common/threading.c'),
   join_paths(zstd_rootdir, 'lib/common/pool.c'),
   join_paths(zstd_rootdir, 'lib/common/zstd_common.c'),
+  join_paths(zstd_rootdir, 'lib/common/zstd_trace.c'),
   join_paths(zstd_rootdir, 'lib/common/error_private.c'),
   join_paths(zstd_rootdir, 'lib/common/xxhash.c'),
   join_paths(zstd_rootdir, 'lib/compress/hist.c'),
@@ -43,7 +45,10 @@ libzstd_sources = [join_paths(zstd_rootdir, 'lib/common/entropy_common.c'),
   join_paths(zstd_rootdir, 'lib/dictBuilder/cover.c'),
   join_paths(zstd_rootdir, 'lib/dictBuilder/fastcover.c'),
   join_paths(zstd_rootdir, 'lib/dictBuilder/divsufsort.c'),
-  join_paths(zstd_rootdir, 'lib/dictBuilder/zdict.c')]
+  join_paths(zstd_rootdir, 'lib/dictBuilder/zdict.c'),
+  join_paths(zstd_rootdir, 'lib/deprecated/zbuff_common.c'),
+  join_paths(zstd_rootdir, 'lib/deprecated/zbuff_compress.c'),
+  join_paths(zstd_rootdir, 'lib/deprecated/zbuff_decompress.c')]
 
 # Explicit define legacy support
 add_project_arguments('-DZSTD_LEGACY_SUPPORT=@0@'.format(legacy_level),
@@ -123,5 +128,5 @@ pkgconfig.generate(libzstd,
   url: 'http://www.zstd.net/')
 
 install_headers(join_paths(zstd_rootdir, 'lib/zstd.h'),
-  join_paths(zstd_rootdir, 'lib/zdict.h'),
-  join_paths(zstd_rootdir, 'lib/zstd_errors.h'))
+  join_paths(zstd_rootdir, 'lib/dictBuilder/zdict.h'),
+  join_paths(zstd_rootdir, 'lib/common/zstd_errors.h'))

contrib/VS2005/fullbench/fullbench.vcproj

@@ -390,7 +390,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File

contrib/VS2005/fuzzer/fuzzer.vcproj

@@ -426,7 +426,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File
@@ -454,7 +454,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File

contrib/VS2005/zstd/zstd.vcproj

@@ -454,7 +454,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File
@@ -482,7 +482,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File

contrib/VS2005/zstdlib/zstdlib.vcproj

@@ -371,6 +371,18 @@
 				RelativePath="..\..\..\lib\common\xxhash.c"
 				>
 			</File>
+			<File
+				RelativePath="..\..\..\lib\deprecated\zbuff_common.c"
+				>
+			</File>
+			<File
+				RelativePath="..\..\..\lib\deprecated\zbuff_compress.c"
+				>
+			</File>
+			<File
+				RelativePath="..\..\..\lib\deprecated\zbuff_decompress.c"
+				>
+			</File>
 			<File
 				RelativePath="..\..\..\lib\dictBuilder\zdict.c"
 				>
@@ -446,7 +458,7 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zstd_errors.h"
+				RelativePath="..\..\..\lib\common\zstd_errors.h"
 				>
 			</File>
 			<File
@@ -474,7 +486,11 @@
 				>
 			</File>
 			<File
-				RelativePath="..\..\..\lib\zdict.h"
+				RelativePath="..\..\..\lib\common\zbuff.h"
+				>
+			</File>
+			<File
+				RelativePath="..\..\..\lib\dictBuilder\zdict.h"
 				>
 			</File>
 			<File

contrib/freestanding_lib/freestanding.py

@@ -481,7 +481,6 @@ class Freestanding(object):
         assert os.path.exists(self._src_lib)
         os.makedirs(self._dst_lib, exist_ok=True)
         self._copy_file("zstd.h")
-        self._copy_file("zstd_errors.h")
         for subdir in INCLUDED_SUBDIRS:
             src_dir = os.path.join(self._src_lib, subdir)
             dst_dir = os.path.join(self._dst_lib, subdir)

contrib/linux-kernel/Makefile

@@ -23,7 +23,7 @@ libzstd:
 		--rewrite-include '<limits\.h>=<linux/limits.h>' \
 		--rewrite-include '<stddef\.h>=<linux/types.h>' \
 		--rewrite-include '"\.\./zstd.h"=<linux/zstd.h>' \
-		--rewrite-include '"(\.\./)?zstd_errors.h"=<linux/zstd_errors.h>' \
+		--rewrite-include '"(\.\./common/)?zstd_errors.h"=<linux/zstd_errors.h>' \
 		--sed 's,/\*\*\*,/* *,g' \
 		--sed 's,/\*\*,/*,g' \
 		-DZSTD_NO_INTRINSICS \
@@ -39,7 +39,6 @@ libzstd:
 		-DZSTD_ADDRESS_SANITIZER=0 \
 		-DZSTD_MEMORY_SANITIZER=0 \
 		-DZSTD_COMPRESS_HEAPMODE=1 \
-		-UZSTD_NO_INLINE \
 		-UNO_PREFETCH \
 		-U__cplusplus \
 		-UZSTD_DLL_EXPORT \
@@ -50,11 +49,13 @@ 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/
+	mv linux/lib/zstd/common/zstd_errors.h linux/include/linux/
 	cp linux_zstd.h linux/include/linux/zstd.h
 	cp zstd_compress_module.c linux/lib/zstd
 	cp zstd_decompress_module.c linux/lib/zstd
@@ -80,7 +81,7 @@ import-upstream:
 	cp -r ../../lib/common $(LINUX)/lib/zstd
 	cp -r ../../lib/compress $(LINUX)/lib/zstd
 	cp -r ../../lib/decompress $(LINUX)/lib/zstd
-	mv $(LINUX)/lib/zstd/zstd_errors.h $(LINUX)/include/linux
+	mv $(LINUX)/lib/zstd/common/zstd_errors.h $(LINUX)/include/linux
 	rm $(LINUX)/lib/zstd/common/threading.*
 	rm $(LINUX)/lib/zstd/common/pool.*
 	rm $(LINUX)/lib/zstd/common/xxhash.*

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.

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.
@@ -11,8 +11,6 @@
 obj-$(CONFIG_ZSTD_COMPRESS) += zstd_compress.o
 obj-$(CONFIG_ZSTD_DECOMPRESS) += zstd_decompress.o
 
-ccflags-y += -O3
-
 zstd_compress-y := \
 		zstd_compress_module.o \
 		common/debug.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.

contrib/linux-kernel/test/Makefile

@@ -11,7 +11,7 @@
 LINUX := ../linux
 LINUX_ZSTDLIB := $(LINUX)/lib/zstd
 
-CPPFLAGS += -I$(LINUX)/include -I$(LINUX_ZSTDLIB) -Iinclude -DNDEBUG -Wno-deprecated-declarations
+CPPFLAGS += -I$(LINUX)/include -I$(LINUX_ZSTDLIB) -Iinclude -DNDEBUG
 # Don't poison the workspace, it currently doesn't work with static allocation and workspace reuse
 CPPFLAGS += -DZSTD_ASAN_DONT_POISON_WORKSPACE
 

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

@@ -18,4 +18,8 @@
 #define noinline __attribute__((noinline))
 #endif
 
+#ifndef fallthrough
+#define fallthrough __attribute__((__fallthrough__))
+#endif
+
 #endif

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

@@ -36,7 +36,6 @@ 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__"

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

@@ -30,9 +30,6 @@ CXXFLAGS ?= -O3 -Wall -Wextra -pedantic
 CPPFLAGS ?=
 LDFLAGS  ?=
 
-# PZstd uses legacy APIs
-CFLAGS   += -Wno-deprecated-declarations
-
 # Include flags
 PZSTD_INC  = -I$(ZSTDDIR) -I$(ZSTDDIR)/common -I$(PROGDIR) -I.
 GTEST_INC  = -isystem googletest/googletest/include

contrib/seekable_format/examples/Makefile

@@ -13,7 +13,7 @@ ZSTDLIB_PATH = ../../../lib
 ZSTDLIB_NAME = libzstd.a
 ZSTDLIB = $(ZSTDLIB_PATH)/$(ZSTDLIB_NAME)
 
-CPPFLAGS += -DXXH_NAMESPACE=ZSTD_ -I../ -I../../../lib -I../../../lib/common
+CPPFLAGS += -I../ -I../../../lib -I../../../lib/common
 
 CFLAGS ?= -O3
 CFLAGS += -g

contrib/seekable_format/examples/parallel_compression.c

@@ -21,6 +21,7 @@
 #  define SLEEP(x) usleep(x * 1000)
 #endif
 
+#define XXH_NAMESPACE ZSTD_
 #include "xxhash.h"
 
 #include "pool.h"      // use zstd thread pool for demo

contrib/seekable_format/examples/seekable_decompression.c

@@ -99,9 +99,6 @@ static void decompressFile_orDie(const char* fname, off_t startOffset, off_t end
 
     while (startOffset < endOffset) {
         size_t const result = ZSTD_seekable_decompress(seekable, buffOut, MIN(endOffset - startOffset, buffOutSize), startOffset);
-        if (!result) {
-            break;
-        }
 
         if (ZSTD_isError(result)) {
             fprintf(stderr, "ZSTD_seekable_decompress() error : %s \n",

contrib/seekable_format/examples/seekable_decompression_mem.c

@@ -104,9 +104,6 @@ static void decompressFile_orDie(const char* fname, off_t startOffset, off_t end
 
     while (startOffset < endOffset) {
         size_t const result = ZSTD_seekable_decompress(seekable, buffOut, MIN(endOffset - startOffset, buffOutSize), startOffset);
-        if (!result) {
-            break;
-        }
 
         if (ZSTD_isError(result)) {
             fprintf(stderr, "ZSTD_seekable_decompress() error : %s \n",

contrib/seekable_format/tests/Makefile

@@ -13,7 +13,7 @@ ZSTDLIB_PATH = ../../../lib
 ZSTDLIB_NAME = libzstd.a
 ZSTDLIB = $(ZSTDLIB_PATH)/$(ZSTDLIB_NAME)
 
-CPPFLAGS += -DXXH_NAMESPACE=ZSTD_ -I../ -I$(ZSTDLIB_PATH) -I$(ZSTDLIB_PATH)/common
+CPPFLAGS += -I../ -I$(ZSTDLIB_PATH) -I$(ZSTDLIB_PATH)/common
 
 CFLAGS ?= -O3
 CFLAGS += -g -Wall -Wextra -Wcast-qual -Wcast-align -Wconversion \

contrib/seekable_format/zstdseek_compress.c

@@ -12,6 +12,7 @@
 #include <assert.h>
 
 #define XXH_STATIC_LINKING_ONLY
+#define XXH_NAMESPACE ZSTD_
 #include "xxhash.h"
 
 #define ZSTD_STATIC_LINKING_ONLY
@@ -82,7 +83,7 @@ static size_t ZSTD_seekable_frameLog_freeVec(ZSTD_frameLog* fl)
 
 ZSTD_frameLog* ZSTD_seekable_createFrameLog(int checksumFlag)
 {
-    ZSTD_frameLog* const fl = (ZSTD_frameLog*)malloc(sizeof(ZSTD_frameLog));
+    ZSTD_frameLog* const fl = malloc(sizeof(ZSTD_frameLog));
     if (fl == NULL) return NULL;
 
     if (ZSTD_isError(ZSTD_seekable_frameLog_allocVec(fl))) {
@@ -107,7 +108,7 @@ size_t ZSTD_seekable_freeFrameLog(ZSTD_frameLog* fl)
 
 ZSTD_seekable_CStream* ZSTD_seekable_createCStream(void)
 {
-    ZSTD_seekable_CStream* const zcs = (ZSTD_seekable_CStream*)malloc(sizeof(ZSTD_seekable_CStream));
+    ZSTD_seekable_CStream* const zcs = malloc(sizeof(ZSTD_seekable_CStream));
     if (zcs == NULL) return NULL;
 
     memset(zcs, 0, sizeof(*zcs));
@@ -176,7 +177,7 @@ size_t ZSTD_seekable_logFrame(ZSTD_frameLog* fl,
     if (fl->size == fl->capacity) {
         /* exponential size increase for constant amortized runtime */
         size_t const newCapacity = fl->capacity * 2;
-        framelogEntry_t* const newEntries = (framelogEntry_t*)realloc(fl->entries,
+        framelogEntry_t* const newEntries = realloc(fl->entries,
                 sizeof(framelogEntry_t) * newCapacity);
 
         if (newEntries == NULL) return ERROR(memory_allocation);

contrib/seekable_format/zstdseek_decompress.c

@@ -60,6 +60,7 @@
 #include <assert.h>
 
 #define XXH_STATIC_LINKING_ONLY
+#define XXH_NAMESPACE ZSTD_
 #include "xxhash.h"
 
 #define ZSTD_STATIC_LINKING_ONLY
@@ -175,7 +176,7 @@ struct ZSTD_seekable_s {
 
 ZSTD_seekable* ZSTD_seekable_create(void)
 {
-    ZSTD_seekable* const zs = (ZSTD_seekable*)malloc(sizeof(ZSTD_seekable));
+    ZSTD_seekable* const zs = malloc(sizeof(ZSTD_seekable));
     if (zs == NULL) return NULL;
 
     /* also initializes stage to zsds_init */
@@ -201,7 +202,7 @@ size_t ZSTD_seekable_free(ZSTD_seekable* zs)
 
 ZSTD_seekTable* ZSTD_seekTable_create_fromSeekable(const ZSTD_seekable* zs)
 {
-    ZSTD_seekTable* const st = (ZSTD_seekTable*)malloc(sizeof(ZSTD_seekTable));
+    ZSTD_seekTable* const st = malloc(sizeof(ZSTD_seekTable));
     if (st==NULL) return NULL;
 
     st->checksumFlag = zs->seekTable.checksumFlag;
@@ -432,11 +433,6 @@ size_t ZSTD_seekable_initAdvanced(ZSTD_seekable* zs, ZSTD_seekable_customFile sr
 
 size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsigned long long offset)
 {
-    unsigned long long const eos = zs->seekTable.entries[zs->seekTable.tableLen].dOffset;
-    if (offset + len > eos) {
-        len = eos - offset;
-    }
-
     U32 targetFrame = ZSTD_seekable_offsetToFrameIndex(zs, offset);
     U32 noOutputProgressCount = 0;
     size_t srcBytesRead = 0;
@@ -453,7 +449,7 @@ size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsign
             zs->in = (ZSTD_inBuffer){zs->inBuff, 0, 0};
             XXH64_reset(&zs->xxhState, 0);
             ZSTD_DCtx_reset(zs->dstream, ZSTD_reset_session_only);
-            if (zs->buffWrapper.size && srcBytesRead > zs->buffWrapper.size) {
+            if (srcBytesRead > zs->buffWrapper.size) {
                 return ERROR(seekableIO);
             }
         }
@@ -506,8 +502,6 @@ size_t ZSTD_seekable_decompress(ZSTD_seekable* zs, void* dst, size_t len, unsign
                 if (zs->decompressedOffset < offset + len) {
                     /* go back to the start and force a reset of the stream */
                     targetFrame = ZSTD_seekable_offsetToFrameIndex(zs, zs->decompressedOffset);
-                    /* in this case it will fail later with corruption_detected, since last block does not have checksum */
-                    assert(targetFrame != zs->seekTable.tableLen);
                 }
                 break;
             }

contrib/single_file_libs/README.md

@@ -11,7 +11,7 @@ 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
+cd zstd/contrib/single_file_libs
 ./combine.sh -r ../../lib -o zstddeclib.c zstddeclib-in.c
 ```
 Then add the resulting file to your project (see the [example files](examples)).
@@ -25,7 +25,7 @@ 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
+cd zstd/contrib/single_file_libs
 ./combine.sh -r ../../lib -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`).

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 1.4.9 Manual</title>
 </head>
 <body>
-<h1>zstd 1.5.0 Manual</h1>
+<h1>zstd 1.4.9 Manual</h1>
 <hr>
 <a name="Contents"></a><h2>Contents</h2>
 <ol>
@@ -12,15 +12,15 @@
 <li><a href="#Chapter2">Version</a></li>
 <li><a href="#Chapter3">Simple API</a></li>
 <li><a href="#Chapter4">Explicit context</a></li>
-<li><a href="#Chapter5">Advanced compression API (Requires v1.4.0+)</a></li>
-<li><a href="#Chapter6">Advanced decompression API (Requires v1.4.0+)</a></li>
+<li><a href="#Chapter5">Advanced compression API</a></li>
+<li><a href="#Chapter6">Advanced decompression API</a></li>
 <li><a href="#Chapter7">Streaming</a></li>
 <li><a href="#Chapter8">Streaming compression - HowTo</a></li>
 <li><a href="#Chapter9">Streaming decompression - HowTo</a></li>
 <li><a href="#Chapter10">Simple dictionary API</a></li>
 <li><a href="#Chapter11">Bulk processing dictionary API</a></li>
 <li><a href="#Chapter12">Dictionary helper functions</a></li>
-<li><a href="#Chapter13">Advanced dictionary and prefix API (Requires v1.4.0+)</a></li>
+<li><a href="#Chapter13">Advanced dictionary and prefix API</a></li>
 <li><a href="#Chapter14">experimental API (static linking only)</a></li>
 <li><a href="#Chapter15">Frame size functions</a></li>
 <li><a href="#Chapter16">Memory management</a></li>
@@ -141,9 +141,8 @@ unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize);
 size_t      ZSTD_compressBound(size_t srcSize); </b>/*!< maximum compressed size in worst case single-pass scenario */<b>
 unsigned    ZSTD_isError(size_t code);          </b>/*!< tells if a `size_t` function result is an error code */<b>
 const char* ZSTD_getErrorName(size_t code);     </b>/*!< provides readable string from an error code */<b>
-int         ZSTD_minCLevel(void);               </b>/*!< minimum negative compression level allowed, requires v1.4.0+ */<b>
+int         ZSTD_minCLevel(void);               </b>/*!< minimum negative compression level allowed */<b>
 int         ZSTD_maxCLevel(void);               </b>/*!< maximum compression level available */<b>
-int         ZSTD_defaultCLevel(void);           </b>/*!< default compression level, specified by ZSTD_CLEVEL_DEFAULT, requires v1.5.0+ */<b>
 </pre></b><BR>
 <a name="Chapter4"></a><h2>Explicit context</h2><pre></pre>
 
@@ -158,7 +157,7 @@ int         ZSTD_defaultCLevel(void);           </b>/*!< default compression lev
  
 </pre><b><pre>typedef struct ZSTD_CCtx_s ZSTD_CCtx;
 ZSTD_CCtx* ZSTD_createCCtx(void);
-size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);  </b>/* accept NULL pointer */<b>
+size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);
 </pre></b><BR>
 <pre><b>size_t ZSTD_compressCCtx(ZSTD_CCtx* cctx,
                          void* dst, size_t dstCapacity,
@@ -180,7 +179,7 @@ size_t     ZSTD_freeCCtx(ZSTD_CCtx* cctx);  </b>/* accept NULL pointer */<b>
   Use one context per thread for parallel execution. 
 </pre><b><pre>typedef struct ZSTD_DCtx_s ZSTD_DCtx;
 ZSTD_DCtx* ZSTD_createDCtx(void);
-size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
+size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);
 </pre></b><BR>
 <pre><b>size_t ZSTD_decompressDCtx(ZSTD_DCtx* dctx,
                            void* dst, size_t dstCapacity,
@@ -191,7 +190,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
  
 </p></pre><BR>
 
-<a name="Chapter5"></a><h2>Advanced compression API (Requires v1.4.0+)</h2><pre></pre>
+<a name="Chapter5"></a><h2>Advanced compression API</h2><pre></pre>
 
 <pre><b>typedef enum { ZSTD_fast=1,
                ZSTD_dfast=2,
@@ -271,6 +270,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
                               * The higher the value of selected strategy, the more complex it is,
                               * resulting in stronger and slower compression.
                               * Special: value 0 means "use default strategy". */
+
     </b>/* LDM mode parameters */<b>
     ZSTD_c_enableLongDistanceMatching=160, </b>/* Enable long distance matching.<b>
                                      * This parameter is designed to improve compression ratio
@@ -327,7 +327,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
     ZSTD_c_jobSize=401,      </b>/* Size of a compression job. This value is enforced only when nbWorkers >= 1.<b>
                               * Each compression job is completed in parallel, so this value can indirectly impact the nb of active threads.
                               * 0 means default, which is dynamically determined based on compression parameters.
-                              * Job size must be a minimum of overlap size, or ZSTDMT_JOBSIZE_MIN (= 512 KB), whichever is largest.
+                              * Job size must be a minimum of overlap size, or 1 MB, whichever is largest.
                               * The minimum size is automatically and transparently enforced. */
     ZSTD_c_overlapLog=402,   </b>/* Control the overlap size, as a fraction of window size.<b>
                               * The overlap size is an amount of data reloaded from previous job at the beginning of a new job.
@@ -357,8 +357,6 @@ 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_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;
      *        also, the enums values themselves are unstable and can still change.
@@ -374,10 +372,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
      ZSTD_c_experimentalParam9=1006,
      ZSTD_c_experimentalParam10=1007,
      ZSTD_c_experimentalParam11=1008,
-     ZSTD_c_experimentalParam12=1009,
-     ZSTD_c_experimentalParam13=1010,
-     ZSTD_c_experimentalParam14=1011,
-     ZSTD_c_experimentalParam15=1012
+     ZSTD_c_experimentalParam12=1009
 } ZSTD_cParameter;
 </b></pre><BR>
 <pre><b>typedef struct {
@@ -461,7 +456,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
  
 </p></pre><BR>
 
-<a name="Chapter6"></a><h2>Advanced decompression API (Requires v1.4.0+)</h2><pre></pre>
+<a name="Chapter6"></a><h2>Advanced decompression API</h2><pre></pre>
 
 <pre><b>typedef enum {
 
@@ -592,7 +587,7 @@ size_t     ZSTD_freeDCtx(ZSTD_DCtx* dctx);  </b>/* accept NULL pointer */<b>
 <pre><b>typedef ZSTD_CCtx ZSTD_CStream;  </b>/**< CCtx and CStream are now effectively same object (>= v1.3.0) */<b>
 </b></pre><BR>
 <h3>ZSTD_CStream management functions</h3><pre></pre><b><pre>ZSTD_CStream* ZSTD_createCStream(void);
-size_t ZSTD_freeCStream(ZSTD_CStream* zcs);  </b>/* accept NULL pointer */<b>
+size_t ZSTD_freeCStream(ZSTD_CStream* zcs);
 </pre></b><BR>
 <h3>Streaming compression functions</h3><pre></pre><b><pre>typedef enum {
     ZSTD_e_continue=0, </b>/* collect more data, encoder decides when to output compressed result, for optimal compression ratio */<b>
@@ -686,7 +681,7 @@ size_t ZSTD_endStream(ZSTD_CStream* zcs, ZSTD_outBuffer* output);
 <pre><b>typedef ZSTD_DCtx ZSTD_DStream;  </b>/**< DCtx and DStream are now effectively same object (>= v1.3.0) */<b>
 </b></pre><BR>
 <h3>ZSTD_DStream management functions</h3><pre></pre><b><pre>ZSTD_DStream* ZSTD_createDStream(void);
-size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
+size_t ZSTD_freeDStream(ZSTD_DStream* zds);
 </pre></b><BR>
 <h3>Streaming decompression functions</h3><pre></pre><b><pre></pre></b><BR>
 <pre><b>size_t ZSTD_DStreamInSize(void);    </b>/*!< recommended size for input buffer */<b>
@@ -702,7 +697,7 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
                                int compressionLevel);
 </b><p>  Compression at an explicit compression level using a Dictionary.
   A dictionary can be any arbitrary data segment (also called a prefix),
-  or a buffer with specified information (see zdict.h).
+  or a buffer with specified information (see dictBuilder/zdict.h).
   Note : This function loads the dictionary, resulting in significant startup delay.
          It's intended for a dictionary used only once.
   Note 2 : When `dict == NULL || dictSize < 8` no dictionary is used. 
@@ -737,8 +732,7 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
 </p></pre><BR>
 
 <pre><b>size_t      ZSTD_freeCDict(ZSTD_CDict* CDict);
-</b><p>  Function frees memory allocated by ZSTD_createCDict().
-  If a NULL pointer is passed, no operation is performed. 
+</b><p>  Function frees memory allocated by ZSTD_createCDict(). 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_compress_usingCDict(ZSTD_CCtx* cctx,
@@ -757,8 +751,7 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
 </p></pre><BR>
 
 <pre><b>size_t      ZSTD_freeDDict(ZSTD_DDict* ddict);
-</b><p>  Function frees memory allocated with ZSTD_createDDict()
-  If a NULL pointer is passed, no operation is performed. 
+</b><p>  Function frees memory allocated with ZSTD_createDDict() 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
@@ -777,12 +770,6 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
   It can still be loaded, but as a content-only dictionary. 
 </p></pre><BR>
 
-<pre><b>unsigned ZSTD_getDictID_fromCDict(const ZSTD_CDict* cdict);
-</b><p>  Provides the dictID of the dictionary loaded into `cdict`.
-  If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
-  Non-conformant dictionaries can still be loaded, but as content-only dictionaries. 
-</p></pre><BR>
-
 <pre><b>unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict* ddict);
 </b><p>  Provides the dictID of the dictionary loaded into `ddict`.
   If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
@@ -801,7 +788,7 @@ size_t ZSTD_freeDStream(ZSTD_DStream* zds);  </b>/* accept NULL pointer */<b>
   When identifying the exact failure cause, it's possible to use ZSTD_getFrameHeader(), which will provide a more precise error code. 
 </p></pre><BR>
 
-<a name="Chapter13"></a><h2>Advanced dictionary and prefix API (Requires v1.4.0+)</h2><pre>
+<a name="Chapter13"></a><h2>Advanced dictionary and prefix API</h2><pre>
  This API allows dictionaries to be used with ZSTD_compress2(),
  ZSTD_compressStream2(), and ZSTD_decompress(). Dictionaries are sticky, and
  only reset with the context is reset with ZSTD_reset_parameters or
@@ -1071,12 +1058,6 @@ size_t ZSTD_sizeof_DDict(const ZSTD_DDict* ddict);
   ZSTD_lcm_uncompressed = 2   </b>/**< Always emit uncompressed literals. */<b>
 } 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></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);
@@ -1313,6 +1294,12 @@ 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>unsigned ZSTD_getDictID_fromCDict(const ZSTD_CDict* cdict);
+</b><p>  Provides the dictID of the dictionary loaded into `cdict`.
+  If @return == 0, the dictionary is not conformant to Zstandard specification, or empty.
+  Non-conformant dictionaries can still be loaded, but as content-only dictionaries. 
+</p></pre><BR>
+
 <pre><b>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 
@@ -1336,26 +1323,24 @@ ZSTD_customMem const ZSTD_defaultCMem = { NULL, NULL, NULL };  </b>/**< this con
   This function never fails (wide contract) 
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_compress2")
-size_t ZSTD_compress_advanced(ZSTD_CCtx* cctx,
+<pre><b>size_t ZSTD_compress_advanced(ZSTD_CCtx* cctx,
                               void* dst, size_t dstCapacity,
                         const void* src, size_t srcSize,
                         const void* dict,size_t dictSize,
                               ZSTD_parameters params);
 </b><p>  Note : this function is now DEPRECATED.
          It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_setParameter() and other parameter setters.
-  This prototype will generate compilation warnings. 
+  This prototype will be marked as deprecated and generate compilation warning on reaching v1.5.x 
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_compress2 with ZSTD_CCtx_loadDictionary")
-size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
+<pre><b>size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
                                   void* dst, size_t dstCapacity,
                             const void* src, size_t srcSize,
                             const ZSTD_CDict* cdict,
                                   ZSTD_frameParameters fParams);
-</b><p>  Note : this function is now DEPRECATED.
+</b><p>  Note : this function is now REDUNDANT.
          It can be replaced by ZSTD_compress2(), in combination with ZSTD_CCtx_loadDictionary() and other parameter setters.
-  This prototype will generate compilation warnings. 
+  This prototype will be marked as deprecated and generate compilation warning in some future version 
 </p></pre><BR>
 
 <pre><b>size_t ZSTD_CCtx_loadDictionary_byReference(ZSTD_CCtx* cctx, const void* dict, size_t dictSize);
@@ -1382,7 +1367,7 @@ size_t ZSTD_compress_usingCDict_advanced(ZSTD_CCtx* cctx,
 </p></pre><BR>
 
 <pre><b>ZSTD_CCtx_params* ZSTD_createCCtxParams(void);
-size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointer */<b>
+size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);
 </b><p>  Quick howto :
   - ZSTD_createCCtxParams() : Create a ZSTD_CCtx_params structure
   - ZSTD_CCtxParams_setParameter() : Push parameters one by one into
@@ -1394,7 +1379,7 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
                                     These parameters will be applied to
                                     all subsequent frames.
   - ZSTD_compressStream2() : Do compression using the CCtx.
-  - ZSTD_freeCCtxParams() : Free the memory, accept NULL pointer.
+  - ZSTD_freeCCtxParams() : Free the memory.
 
   This can be used with ZSTD_estimateCCtxSize_advanced_usingCCtxParams()
   for static allocation of CCtx for single-threaded compression.
@@ -1508,10 +1493,8 @@ size_t ZSTD_freeCCtxParams(ZSTD_CCtx_params* params);  </b>/* accept NULL pointe
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_DCtx_setParameter() instead")
-size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);
-</b><p>  This function is REDUNDANT. Prefer ZSTD_DCtx_setParameter().
-  Instruct the decoder context about what kind of data to decode next.
+<pre><b>size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);
+</b><p>  Instruct the decoder context about what kind of data to decode next.
   This instruction is mandatory to decode data without a fully-formed header,
   such ZSTD_f_zstd1_magicless for example.
  @return : 0, or an error code (which can be tested using ZSTD_isError()). 
@@ -1534,11 +1517,11 @@ size_t ZSTD_DCtx_setFormat(ZSTD_DCtx* dctx, ZSTD_format_e format);
 <BR></pre>
 
 <h3>Advanced Streaming compression functions</h3><pre></pre><b><pre></pre></b><BR>
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions")
-size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs,
+<pre><b>size_t
+ZSTD_initCStream_srcSize(ZSTD_CStream* zcs,
              int compressionLevel,
              unsigned long long pledgedSrcSize);
-</b><p> This function is DEPRECATED, and equivalent to:
+</b><p> This function is deprecated, and equivalent to:
      ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
      ZSTD_CCtx_refCDict(zcs, NULL); // clear the dictionary (if any)
      ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel);
@@ -1547,15 +1530,15 @@ size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs,
  pledgedSrcSize must be correct. If it is not known at init time, use
  ZSTD_CONTENTSIZE_UNKNOWN. Note that, for compatibility with older programs,
  "0" also disables frame content size field. It may be enabled in the future.
- This prototype will generate compilation warnings.
+ Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions")
-size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs,
+<pre><b>size_t
+ZSTD_initCStream_usingDict(ZSTD_CStream* zcs,
          const void* dict, size_t dictSize,
                int compressionLevel);
-</b><p> This function is DEPRECATED, and is equivalent to:
+</b><p> This function is deprecated, and is equivalent to:
      ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
      ZSTD_CCtx_setParameter(zcs, ZSTD_c_compressionLevel, compressionLevel);
      ZSTD_CCtx_loadDictionary(zcs, dict, dictSize);
@@ -1564,16 +1547,16 @@ size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs,
  dict == NULL or dictSize < 8, in which case no dict is used.
  Note: dict is loaded with ZSTD_dct_auto (treated as a full zstd dictionary if
  it begins with ZSTD_MAGIC_DICTIONARY, else as raw content) and ZSTD_dlm_byCopy.
- This prototype will generate compilation warnings.
+ Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions")
-size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
+<pre><b>size_t
+ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
         const void* dict, size_t dictSize,
               ZSTD_parameters params,
               unsigned long long pledgedSrcSize);
-</b><p> This function is DEPRECATED, and is approximately equivalent to:
+</b><p> This function is deprecated, and is approximately equivalent to:
      ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
      // Pseudocode: Set each zstd parameter and leave the rest as-is.
      for ((param, value) : params) {
@@ -1585,23 +1568,22 @@ size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
  dict is loaded with ZSTD_dct_auto and ZSTD_dlm_byCopy.
  pledgedSrcSize must be correct.
  If srcSize is not known at init time, use value ZSTD_CONTENTSIZE_UNKNOWN.
- This prototype will generate compilation warnings.
+ Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset and ZSTD_CCtx_refCDict, see zstd.h for detailed instructions")
-size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);
-</b><p> This function is DEPRECATED, and equivalent to:
+<pre><b>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.
+ Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset and ZSTD_CCtx_refCDict, see zstd.h for detailed instructions")
-size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
+<pre><b>size_t
+ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
                    const ZSTD_CDict* cdict,
                          ZSTD_frameParameters fParams,
                          unsigned long long pledgedSrcSize);
@@ -1617,18 +1599,14 @@ size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs,
  same as ZSTD_initCStream_usingCDict(), with control over frame parameters.
  pledgedSrcSize must be correct. If srcSize is not known at init time, use
  value ZSTD_CONTENTSIZE_UNKNOWN.
- This prototype will generate compilation warnings.
+ Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
-<pre><b>ZSTD_DEPRECATED("use ZSTD_CCtx_reset, see zstd.h for detailed instructions")
-size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
-</b><p> This function is DEPRECATED, and is equivalent to:
+<pre><b>size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
+</b><p> This function is deprecated, and is equivalent to:
      ZSTD_CCtx_reset(zcs, ZSTD_reset_session_only);
      ZSTD_CCtx_setPledgedSrcSize(zcs, pledgedSrcSize);
- Note: ZSTD_resetCStream() interprets pledgedSrcSize == 0 as ZSTD_CONTENTSIZE_UNKNOWN, but
-       ZSTD_CCtx_setPledgedSrcSize() does not do the same, so ZSTD_CONTENTSIZE_UNKNOWN must be
-       explicitly specified.
 
   start a new frame, using same parameters from previous frame.
   This is typically useful to skip dictionary loading stage, since it will re-use it in-place.
@@ -1638,7 +1616,7 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
   For the time being, pledgedSrcSize==0 is interpreted as "srcSize unknown" for compatibility with older programs,
   but it will change to mean "empty" in future version, so use macro ZSTD_CONTENTSIZE_UNKNOWN instead.
  @return : 0, or an error code (which can be tested using ZSTD_isError())
-  This prototype will generate compilation warnings.
+  Note : this prototype will be marked as deprecated and generate compilation warnings on reaching v1.5.x
  
 </p></pre><BR>
 
@@ -1709,7 +1687,8 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
   ZSTD_CCtx object can be re-used multiple times within successive compression operations.
 
   Start by initializing a context.
-  Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary compression.
+  Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary compression,
+  or ZSTD_compressBegin_advanced(), for finer parameter control.
   It's also possible to duplicate a reference context which has already been initialized, using ZSTD_copyCCtx()
 
   Then, consume your input using ZSTD_compressContinue().
@@ -1733,11 +1712,11 @@ size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize);
 
 <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_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>
 size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx* cctx, const ZSTD_CDict* cdict); </b>/**< note: fails if cdict==NULL */<b>
+size_t ZSTD_compressBegin_usingCDict_advanced(ZSTD_CCtx* const cctx, const ZSTD_CDict* const cdict, ZSTD_frameParameters const fParams, unsigned long long const pledgedSrcSize);   </b>/* compression parameters are already set within cdict. pledgedSrcSize must be correct. If srcSize is not known, use macro ZSTD_CONTENTSIZE_UNKNOWN */<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>
 </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>
 <a name="Chapter22"></a><h2>Buffer-less streaming decompression (synchronous mode)</h2><pre>
   A ZSTD_DCtx object is required to track streaming operations.
   Use ZSTD_createDCtx() / ZSTD_freeDCtx() to manage it.

lib/BUCK

@@ -65,7 +65,9 @@ cxx_library(
     name='zdict',
     header_namespace='',
     visibility=['PUBLIC'],
-    exported_headers=['zdict.h'],
+    exported_headers=subdir_glob([
+        ('dictBuilder', 'zdict.h'),
+    ]),
     headers=subdir_glob([
         ('dictBuilder', 'divsufsort.h'),
         ('dictBuilder', 'cover.h'),
@@ -129,10 +131,10 @@ cxx_library(
     name='errors',
     header_namespace='',
     visibility=['PUBLIC'],
-    exported_headers=[
-        'zstd_errors.h',
-        'common/error_private.h',
-    ]
+    exported_headers=subdir_glob([
+        ('common', 'error_private.h'),
+        ('common', 'zstd_errors.h'),
+    ]),
     srcs=['common/error_private.c'],
 )
 

lib/Makefile

@@ -8,9 +8,6 @@
 # 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
 
@@ -71,10 +68,6 @@ DEBUGFLAGS= -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
 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)
@@ -98,7 +91,7 @@ endif
 ZSTD_LIB_COMPRESSION ?= 1
 ZSTD_LIB_DECOMPRESSION ?= 1
 ZSTD_LIB_DICTBUILDER ?= 1
-ZSTD_LIB_DEPRECATED ?= 0
+ZSTD_LIB_DEPRECATED ?= 1
 
 # Legacy support
 ZSTD_LEGACY_SUPPORT ?= 5
@@ -183,9 +176,7 @@ UNAME := $(shell uname)
 
 ifndef BUILD_DIR
 ifeq ($(UNAME), Darwin)
-  ifeq ($(shell md5 < /dev/null > /dev/null; echo $$?), 0)
-    HASH ?= md5
-  endif
+  HASH ?= md5
 else ifeq ($(UNAME), FreeBSD)
   HASH ?= gmd5sum
 else ifeq ($(UNAME), NetBSD)
@@ -231,7 +222,6 @@ all: lib
 
 
 .PHONY: libzstd.a  # must be run every time
-libzstd.a: CPPFLAGS += $(CPPFLAGS_STATLIB)
 
 ifndef BUILD_DIR
 # determine BUILD_DIR from compilation flags
@@ -248,10 +238,7 @@ ZSTD_STATLIB_OBJ := $(addprefix $(ZSTD_STATLIB_DIR)/,$(ZSTD_LOCAL_OBJ))
 $(ZSTD_STATLIB): ARFLAGS = rcs
 $(ZSTD_STATLIB): | $(ZSTD_STATLIB_DIR)
 $(ZSTD_STATLIB): $(ZSTD_STATLIB_OBJ)
-  # Check for multithread flag at target execution time
-	$(if $(filter -DZSTD_MULTITHREAD,$(CPPFLAGS)),\
-    @echo compiling multi-threaded static library $(LIBVER),\
-    @echo compiling single-threaded static library $(LIBVER))
+	@echo compiling static library
 	$(AR) $(ARFLAGS) $@ $^
 
 libzstd.a: $(ZSTD_STATLIB)
@@ -270,9 +257,8 @@ else  # not Windows
 
 LIBZSTD = libzstd.$(SHARED_EXT_VER)
 .PHONY: $(LIBZSTD)  # must be run every time
-$(LIBZSTD): CPPFLAGS += $(CPPFLAGS_DYNLIB)
-$(LIBZSTD): CFLAGS   += -fPIC -fvisibility=hidden
-$(LIBZSTD): LDFLAGS  += -shared $(LDFLAGS_DYNLIB)
+$(LIBZSTD): CFLAGS += -fPIC -fvisibility=hidden
+$(LIBZSTD): LDFLAGS += -shared
 
 ifndef BUILD_DIR
 # determine BUILD_DIR from compilation flags
@@ -289,10 +275,7 @@ ZSTD_DYNLIB_OBJ := $(addprefix $(ZSTD_DYNLIB_DIR)/,$(ZSTD_LOCAL_OBJ))
 
 $(ZSTD_DYNLIB): | $(ZSTD_DYNLIB_DIR)
 $(ZSTD_DYNLIB): $(ZSTD_DYNLIB_OBJ)
-# Check for multithread flag at target execution time
-	$(if $(filter -DZSTD_MULTITHREAD,$(CPPFLAGS)),\
-    @echo compiling multi-threaded dynamic library $(LIBVER),\
-    @echo compiling single-threaded dynamic library $(LIBVER))
+	@echo compiling dynamic library $(LIBVER)
 	$(CC) $(FLAGS) $^ $(LDFLAGS) $(SONAME_FLAGS) -o $@
 	@echo creating versioned links
 	ln -sf $@ libzstd.$(SHARED_EXT_MAJOR)
@@ -314,17 +297,10 @@ lib : libzstd.a libzstd
 # note : do not define lib-mt or lib-release as .PHONY
 # make does not consider implicit pattern rule for .PHONY target
 
-%-mt : CPPFLAGS_DYNLIB  := -DZSTD_MULTITHREAD
-%-mt : CPPFLAGS_STATLIB := -DZSTD_MULTITHREAD
-%-mt : LDFLAGS_DYNLIB   := -pthread
+%-mt : CPPFLAGS += -DZSTD_MULTITHREAD
+%-mt : LDFLAGS  += -pthread
 %-mt : %
-	@echo multi-threaded build completed
-
-%-nomt : CPPFLAGS_DYNLIB  :=
-%-nomt : LDFLAGS_DYNLIB   :=
-%-nomt : CPPFLAGS_STATLIB :=
-%-nomt : %
-	@echo single-threaded build completed
+	@echo multi-threading build completed
 
 %-release : DEBUGFLAGS :=
 %-release : %
@@ -356,8 +332,7 @@ include $(wildcard $(DEPFILES))
 # Special case : building library in single-thread mode _and_ without zstdmt_compress.c
 ZSTDMT_FILES = compress/zstdmt_compress.c
 ZSTD_NOMT_FILES = $(filter-out $(ZSTDMT_FILES),$(ZSTD_FILES))
-libzstd-nomt: CFLAGS += -fPIC -fvisibility=hidden
-libzstd-nomt: LDFLAGS += -shared
+libzstd-nomt: LDFLAGS += -shared -fPIC -fvisibility=hidden
 libzstd-nomt: $(ZSTD_NOMT_FILES)
 	@echo compiling single-thread dynamic library $(LIBVER)
 	@echo files : $(ZSTD_NOMT_FILES)
@@ -436,12 +411,10 @@ libzstd.pc: libzstd.pc.in
 install: install-pc install-static install-shared install-includes
 	@echo zstd static and shared library installed
 
-.PHONY: install-pc
 install-pc: libzstd.pc
 	[ -e $(DESTDIR)$(PKGCONFIGDIR) ] || $(INSTALL) -d -m 755 $(DESTDIR)$(PKGCONFIGDIR)/
 	$(INSTALL_DATA) libzstd.pc $(DESTDIR)$(PKGCONFIGDIR)/
 
-.PHONY: install-static
 install-static:
 	# only generate libzstd.a if it's not already present
 	[ -e libzstd.a ] || $(MAKE) libzstd.a-release
@@ -449,7 +422,6 @@ install-static:
 	@echo Installing static library
 	$(INSTALL_DATA) libzstd.a $(DESTDIR)$(LIBDIR)
 
-.PHONY: install-shared
 install-shared:
 	# only generate libzstd.so if it's not already present
 	[ -e $(LIBZSTD) ] || $(MAKE) libzstd-release
@@ -459,13 +431,12 @@ install-shared:
 	ln -sf $(LIBZSTD) $(DESTDIR)$(LIBDIR)/libzstd.$(SHARED_EXT_MAJOR)
 	ln -sf $(LIBZSTD) $(DESTDIR)$(LIBDIR)/libzstd.$(SHARED_EXT)
 
-.PHONY: install-includes
 install-includes:
 	[ -e $(DESTDIR)$(INCLUDEDIR) ] || $(INSTALL) -d -m 755 $(DESTDIR)$(INCLUDEDIR)/
 	@echo Installing includes
 	$(INSTALL_DATA) zstd.h $(DESTDIR)$(INCLUDEDIR)
-	$(INSTALL_DATA) zstd_errors.h $(DESTDIR)$(INCLUDEDIR)
-	$(INSTALL_DATA) zdict.h $(DESTDIR)$(INCLUDEDIR)
+	$(INSTALL_DATA) common/zstd_errors.h $(DESTDIR)$(INCLUDEDIR)
+	$(INSTALL_DATA) dictBuilder/zdict.h $(DESTDIR)$(INCLUDEDIR)
 
 .PHONY: uninstall
 uninstall:

lib/README.md

@@ -19,16 +19,12 @@ The scope can be reduced on demand (see paragraph _modular build_).
 
 #### Multithreading support
 
-When building with `make`, by default the dynamic library is multithreaded and static library is single-threaded (for compatibility reasons).
-
+Multithreading is disabled by default when building with `make`.
 Enabling multithreading requires 2 conditions :
 - set build macro `ZSTD_MULTITHREAD` (`-DZSTD_MULTITHREAD` for `gcc`)
 - for POSIX systems : compile with pthread (`-pthread` compilation flag for `gcc`)
 
-For convenience, we provide a build target to generate multi and single threaded libraries:
-- Force enable multithreading on both dynamic and static libraries by appending `-mt` to the target, e.g. `make lib-mt`.
-- Force disable multithreading on both dynamic and static libraries by appending `-nomt` to the target, e.g. `make lib-nomt`.
-- By default, as mentioned before, dynamic library is multithreaded, and static library is single-threaded, e.g. `make lib`.
+Both conditions are automatically applied when invoking `make lib-mt` target.
 
 When linking a POSIX program with a multithreaded version of `libzstd`,
 note that it's necessary to invoke the `-pthread` flag during link stage.
@@ -46,8 +42,8 @@ Zstandard's stable API is exposed within [lib/zstd.h](zstd.h).
 
 Optional advanced features are exposed via :
 
-- `lib/zstd_errors.h` : translates `size_t` function results
-                        into a `ZSTD_ErrorCode`, for accurate error handling.
+- `lib/common/zstd_errors.h` : translates `size_t` function results
+                               into a `ZSTD_ErrorCode`, for accurate error handling.
 
 - `ZSTD_STATIC_LINKING_ONLY` : if this macro is defined _before_ including `zstd.h`,
                           it unlocks access to the experimental API,

lib/common/bitstream.h

@@ -293,22 +293,22 @@ 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;
         }

lib/common/compiler.h

@@ -207,6 +207,39 @@
 #  define __has_feature(x) 0
 #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__)
+#  define ZSTD_FALLTHROUGH __attribute__((__fallthrough__))
+# else
+#  define ZSTD_FALLTHROUGH
+# endif
+#endif
+
 /* detects whether we are being compiled under msan */
 #ifndef ZSTD_MEMORY_SANITIZER
 #  if __has_feature(memory_sanitizer)

lib/common/error_private.h

@@ -21,8 +21,8 @@ extern "C" {
 /* ****************************************
 *  Dependencies
 ******************************************/
-#include "../zstd_errors.h"  /* enum list */
-#include "zstd_deps.h"       /* size_t */
+#include "zstd_deps.h"    /* size_t */
+#include "zstd_errors.h"  /* enum list */
 
 
 /* ****************************************

lib/common/mem.h

@@ -143,7 +143,9 @@ MEM_STATIC size_t MEM_swapST(size_t in);
  * Prefer these methods in priority order (0 > 1 > 2)
  */
 #ifndef MEM_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
-#  if defined(__INTEL_COMPILER) || defined(__GNUC__) || defined(__ICCARM__)
+#  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
+#    define MEM_FORCE_MEMORY_ACCESS 2
+#  elif defined(__INTEL_COMPILER) || defined(__GNUC__) || defined(__ICCARM__)
 #    define MEM_FORCE_MEMORY_ACCESS 1
 #  endif
 #endif

lib/common/xxhash.c

@@ -30,7 +30,9 @@
  * Prefer these methods in priority order (0 > 1 > 2)
  */
 #ifndef XXH_FORCE_MEMORY_ACCESS   /* can be defined externally, on command line for example */
-#  if (defined(__INTEL_COMPILER) && !defined(WIN32)) || \
+#  if defined(__GNUC__) && ( defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) )
+#    define XXH_FORCE_MEMORY_ACCESS 2
+#  elif (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

lib/common/zstd_internal.h

@@ -352,18 +352,11 @@ typedef enum {
 *  Private declarations
 *********************************************/
 typedef struct seqDef_s {
-    U32 offset;         /* offset == rawOffset + ZSTD_REP_NUM, or equivalently, offCode + 1 */
+    U32 offset;         /* Offset code of the sequence */
     U16 litLength;
     U16 matchLength;
 } seqDef;
 
-/* Controls whether seqStore has a single "long" litLength or matchLength. See seqStore_t. */
-typedef enum {
-    ZSTD_llt_none = 0,             /* no longLengthType */
-    ZSTD_llt_literalLength = 1,    /* represents a long literal */
-    ZSTD_llt_matchLength = 2       /* represents a long match */
-} ZSTD_longLengthType_e;
-
 typedef struct {
     seqDef* sequencesStart;
     seqDef* sequences;      /* ptr to end of sequences */
@@ -375,12 +368,12 @@ typedef struct {
     size_t maxNbSeq;
     size_t maxNbLit;
 
-    /* longLengthPos and longLengthType to allow us to represent either a single litLength or matchLength
+    /* longLengthPos and longLengthID to allow us to represent either a single litLength or matchLength
      * in the seqStore that has a value larger than U16 (if it exists). To do so, we increment
      * the existing value of the litLength or matchLength by 0x10000.
      */
-    ZSTD_longLengthType_e   longLengthType;
-    U32                     longLengthPos;  /* Index of the sequence to apply long length modification to */
+    U32   longLengthID;   /* 0 == no longLength; 1 == Represent the long literal; 2 == Represent the long match; */
+    U32   longLengthPos;  /* Index of the sequence to apply long length modification to */
 } seqStore_t;
 
 typedef struct {
@@ -390,7 +383,7 @@ typedef struct {
 
 /**
  * Returns the ZSTD_sequenceLength for the given sequences. It handles the decoding of long sequences
- * indicated by longLengthPos and longLengthType, and adds MINMATCH back to matchLength.
+ * indicated by longLengthPos and longLengthID, and adds MINMATCH back to matchLength.
  */
 MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore, seqDef const* seq)
 {
@@ -398,10 +391,10 @@ MEM_STATIC ZSTD_sequenceLength ZSTD_getSequenceLength(seqStore_t const* seqStore
     seqLen.litLength = seq->litLength;
     seqLen.matchLength = seq->matchLength + MINMATCH;
     if (seqStore->longLengthPos == (U32)(seq - seqStore->sequencesStart)) {
-        if (seqStore->longLengthType == ZSTD_llt_literalLength) {
+        if (seqStore->longLengthID == 1) {
             seqLen.litLength += 0xFFFF;
         }
-        if (seqStore->longLengthType == ZSTD_llt_matchLength) {
+        if (seqStore->longLengthID == 2) {
             seqLen.matchLength += 0xFFFF;
         }
     }

lib/common/zstd_trace.c

@@ -0,0 +1,42 @@
+/*
+ * 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.
+ */
+
+#include "zstd_trace.h"
+#include "../zstd.h"
+
+#include "compiler.h"
+
+#if ZSTD_TRACE && ZSTD_HAVE_WEAK_SYMBOLS
+
+ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_compress_begin(ZSTD_CCtx const* cctx)
+{
+    (void)cctx;
+    return 0;
+}
+
+ZSTD_WEAK_ATTR void ZSTD_trace_compress_end(ZSTD_TraceCtx ctx, ZSTD_Trace const* trace)
+{
+    (void)ctx;
+    (void)trace;
+}
+
+ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_decompress_begin(ZSTD_DCtx const* dctx)
+{
+    (void)dctx;
+    return 0;
+}
+
+ZSTD_WEAK_ATTR void ZSTD_trace_decompress_end(ZSTD_TraceCtx ctx, ZSTD_Trace const* trace)
+{
+    (void)ctx;
+    (void)trace;
+}
+
+#endif

lib/common/zstd_trace.h

@@ -114,15 +114,14 @@ typedef unsigned long long ZSTD_TraceCtx;
  * @returns Non-zero if tracing is enabled. The return value is
  *          passed to ZSTD_trace_compress_end().
  */
-ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_compress_begin(
-    struct ZSTD_CCtx_s const* cctx);
+ZSTD_TraceCtx ZSTD_trace_compress_begin(struct ZSTD_CCtx_s const* cctx);
 
 /**
  * Trace the end of a compression call.
  * @param ctx The return value of ZSTD_trace_compress_begin().
  * @param trace The zstd tracing info.
  */
-ZSTD_WEAK_ATTR void ZSTD_trace_compress_end(
+void ZSTD_trace_compress_end(
     ZSTD_TraceCtx ctx,
     ZSTD_Trace const* trace);
 
@@ -133,15 +132,14 @@ ZSTD_WEAK_ATTR void ZSTD_trace_compress_end(
  * @returns Non-zero if tracing is enabled. The return value is
  *          passed to ZSTD_trace_compress_end().
  */
-ZSTD_WEAK_ATTR ZSTD_TraceCtx ZSTD_trace_decompress_begin(
-    struct ZSTD_DCtx_s const* dctx);
+ZSTD_TraceCtx ZSTD_trace_decompress_begin(struct ZSTD_DCtx_s const* dctx);
 
 /**
  * Trace the end of a decompression call.
  * @param ctx The return value of ZSTD_trace_decompress_begin().
  * @param trace The zstd tracing info.
  */
-ZSTD_WEAK_ATTR void ZSTD_trace_decompress_end(
+void ZSTD_trace_decompress_end(
     ZSTD_TraceCtx ctx,
     ZSTD_Trace const* trace);
 

lib/compress/huf_compress.c

@@ -596,16 +596,19 @@ HUF_compress1X_usingCTable_internal_body(void* dst, size_t dstSize,
     n = srcSize & ~3;  /* join to mod 4 */
     switch (srcSize & 3)
     {
-        case 3 : HUF_encodeSymbol(&bitC, ip[n+ 2], CTable);
-                 HUF_FLUSHBITS_2(&bitC);
-		 /* fall-through */
-        case 2 : HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
-                 HUF_FLUSHBITS_1(&bitC);
-		 /* fall-through */
-        case 1 : HUF_encodeSymbol(&bitC, ip[n+ 0], CTable);
-                 HUF_FLUSHBITS(&bitC);
-		 /* fall-through */
-        case 0 : /* fall-through */
+        case 3:
+            HUF_encodeSymbol(&bitC, ip[n+ 2], CTable);
+            HUF_FLUSHBITS_2(&bitC);
+            ZSTD_FALLTHROUGH;
+        case 2:
+            HUF_encodeSymbol(&bitC, ip[n+ 1], CTable);
+            HUF_FLUSHBITS_1(&bitC);
+            ZSTD_FALLTHROUGH;
+        case 1:
+            HUF_encodeSymbol(&bitC, ip[n+ 0], CTable);
+            HUF_FLUSHBITS(&bitC);
+            ZSTD_FALLTHROUGH;
+        case 0: ZSTD_FALLTHROUGH;
         default: break;
     }
 

lib/compress/zstd_compress_internal.h

@@ -81,53 +81,6 @@ typedef struct {
     ZSTD_fseCTables_t fse;
 } ZSTD_entropyCTables_t;
 
-/***********************************************
-*  Entropy buffer statistics structs and funcs *
-***********************************************/
-/** ZSTD_hufCTablesMetadata_t :
- *  Stores Literals Block Type for a super-block in hType, and
- *  huffman tree description in hufDesBuffer.
- *  hufDesSize refers to the size of huffman tree description in bytes.
- *  This metadata is populated in ZSTD_buildBlockEntropyStats_literals() */
-typedef struct {
-    symbolEncodingType_e hType;
-    BYTE hufDesBuffer[ZSTD_MAX_HUF_HEADER_SIZE];
-    size_t hufDesSize;
-} ZSTD_hufCTablesMetadata_t;
-
-/** ZSTD_fseCTablesMetadata_t :
- *  Stores symbol compression modes for a super-block in {ll, ol, ml}Type, and
- *  fse tables in fseTablesBuffer.
- *  fseTablesSize refers to the size of fse tables in bytes.
- *  This metadata is populated in ZSTD_buildBlockEntropyStats_sequences() */
-typedef struct {
-    symbolEncodingType_e llType;
-    symbolEncodingType_e ofType;
-    symbolEncodingType_e mlType;
-    BYTE fseTablesBuffer[ZSTD_MAX_FSE_HEADERS_SIZE];
-    size_t fseTablesSize;
-    size_t lastCountSize; /* This is to account for bug in 1.3.4. More detail in ZSTD_entropyCompressSeqStore_internal() */
-} ZSTD_fseCTablesMetadata_t;
-
-typedef struct {
-    ZSTD_hufCTablesMetadata_t hufMetadata;
-    ZSTD_fseCTablesMetadata_t fseMetadata;
-} ZSTD_entropyCTablesMetadata_t;
-
-/** ZSTD_buildBlockEntropyStats() :
- *  Builds entropy for the block.
- *  @return : 0 on success or error code */
-size_t ZSTD_buildBlockEntropyStats(seqStore_t* seqStorePtr,
-                             const ZSTD_entropyCTables_t* prevEntropy,
-                                   ZSTD_entropyCTables_t* nextEntropy,
-                             const ZSTD_CCtx_params* cctxParams,
-                                   ZSTD_entropyCTablesMetadata_t* entropyMetadata,
-                                   void* workspace, size_t wkspSize);
-
-/*********************************
-*  Compression internals structs *
-*********************************/
-
 typedef struct {
     U32 off;            /* Offset code (offset + ZSTD_REP_MOVE) for the match */
     U32 len;            /* Raw length of match */
@@ -188,21 +141,14 @@ typedef struct {
 } ZSTD_compressedBlockState_t;
 
 typedef struct {
-    BYTE const* nextSrc;       /* next block here to continue on current prefix */
-    BYTE const* base;          /* All regular indexes relative to this position */
-    BYTE const* dictBase;      /* extDict indexes relative to this position */
-    U32 dictLimit;             /* below that point, need extDict */
-    U32 lowLimit;              /* below that point, no more valid data */
-    U32 nbOverflowCorrections; /* Number of times overflow correction has run since
-                                * ZSTD_window_init(). Useful for debugging coredumps
-                                * and for ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY.
-                                */
+    BYTE const* nextSrc;    /* next block here to continue on current prefix */
+    BYTE const* base;       /* All regular indexes relative to this position */
+    BYTE const* dictBase;   /* extDict indexes relative to this position */
+    U32 dictLimit;          /* below that point, need extDict */
+    U32 lowLimit;           /* below that point, no more valid data */
 } ZSTD_window_t;
 
 typedef struct ZSTD_matchState_t ZSTD_matchState_t;
-
-#define ZSTD_ROW_HASH_CACHE_SIZE 8       /* Size of prefetching hash cache for row-based matchfinder */
-
 struct ZSTD_matchState_t {
     ZSTD_window_t window;   /* State for window round buffer management */
     U32 loadedDictEnd;      /* index of end of dictionary, within context's referential.
@@ -214,17 +160,9 @@ struct ZSTD_matchState_t {
                              */
     U32 nextToUpdate;       /* index from which to continue table update */
     U32 hashLog3;           /* dispatch table for matches of len==3 : larger == faster, more memory */
-
-    U32 rowHashLog;                          /* For row-based matchfinder: Hashlog based on nb of rows in the hashTable.*/
-    U16* tagTable;                           /* For row-based matchFinder: A row-based table containing the hashes and head index. */
-    U32 hashCache[ZSTD_ROW_HASH_CACHE_SIZE]; /* For row-based matchFinder: a cache of hashes to improve speed */
-
     U32* hashTable;
     U32* hashTable3;
     U32* chainTable;
-
-    U32 forceNonContiguous; /* Non-zero if we should force non-contiguous load for the next window update. */
-
     int dedicatedDictSearch;  /* Indicates whether this matchState is using the
                                * dedicated dictionary search structure.
                                */
@@ -317,15 +255,6 @@ struct ZSTD_CCtx_params_s {
     ZSTD_sequenceFormat_e blockDelimiters;
     int validateSequences;
 
-    /* Block splitting */
-    int splitBlocks;
-
-    /* Param for deciding whether to use row-based matchfinder */
-    ZSTD_useRowMatchFinderMode_e useRowMatchFinder;
-
-    /* Always load a dictionary in ext-dict mode (not prefix mode)? */
-    int deterministicRefPrefix;
-
     /* Internal use, for createCCtxParams() and freeCCtxParams() only */
     ZSTD_customMem customMem;
 };  /* typedef'd to ZSTD_CCtx_params within "zstd.h" */
@@ -349,7 +278,6 @@ struct ZSTD_CCtx_s {
     int bmi2;                            /* == 1 if the CPU supports BMI2 and 0 otherwise. CPU support is determined dynamically once per context lifetime. */
     ZSTD_CCtx_params requestedParams;
     ZSTD_CCtx_params appliedParams;
-    ZSTD_CCtx_params simpleApiParams;    /* Param storage used by the simple API - not sticky. Must only be used in top-level simple API functions for storage. */
     U32   dictID;
     size_t dictContentSize;
 
@@ -442,7 +370,7 @@ 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_dictMode_e dictMode);
 
 
 MEM_STATIC U32 ZSTD_LLcode(U32 litLength)
@@ -558,7 +486,7 @@ MEM_STATIC int ZSTD_disableLiteralsCompression(const ZSTD_CCtx_params* cctxParam
         return 1;
     default:
         assert(0 /* impossible: pre-validated */);
-        /* fall-through */
+        ZSTD_FALLTHROUGH;
     case ZSTD_lcm_auto:
         return (cctxParams->cParams.strategy == ZSTD_fast) && (cctxParams->cParams.targetLength > 0);
     }
@@ -619,8 +547,8 @@ void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* litera
 
     /* literal Length */
     if (litLength>0xFFFF) {
-        assert(seqStorePtr->longLengthType == ZSTD_llt_none); /* there can only be a single long length */
-        seqStorePtr->longLengthType = ZSTD_llt_literalLength;
+        assert(seqStorePtr->longLengthID == 0); /* there can only be a single long length */
+        seqStorePtr->longLengthID = 1;
         seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
     }
     seqStorePtr->sequences[0].litLength = (U16)litLength;
@@ -630,8 +558,8 @@ void ZSTD_storeSeq(seqStore_t* seqStorePtr, size_t litLength, const BYTE* litera
 
     /* match Length */
     if (mlBase>0xFFFF) {
-        assert(seqStorePtr->longLengthType == ZSTD_llt_none); /* there can only be a single long length */
-        seqStorePtr->longLengthType = ZSTD_llt_matchLength;
+        assert(seqStorePtr->longLengthID == 0); /* there can only be a single long length */
+        seqStorePtr->longLengthID = 2;
         seqStorePtr->longLengthPos = (U32)(seqStorePtr->sequences - seqStorePtr->sequencesStart);
     }
     seqStorePtr->sequences[0].matchLength = (U16)mlBase;
@@ -882,13 +810,6 @@ MEM_STATIC void ZSTD_window_clear(ZSTD_window_t* window)
     window->dictLimit = end;
 }
 
-MEM_STATIC U32 ZSTD_window_isEmpty(ZSTD_window_t const window)
-{
-    return window.dictLimit == 1 &&
-           window.lowLimit == 1 &&
-           (window.nextSrc - window.base) == 1;
-}
-
 /**
  * ZSTD_window_hasExtDict():
  * Returns non-zero if the window has a non-empty extDict.
@@ -912,69 +833,15 @@ MEM_STATIC ZSTD_dictMode_e ZSTD_matchState_dictMode(const ZSTD_matchState_t *ms)
             ZSTD_noDict;
 }
 
-/* Defining this macro to non-zero tells zstd to run the overflow correction
- * code much more frequently. This is very inefficient, and should only be
- * used for tests and fuzzers.
- */
-#ifndef ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY
-#  ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
-#    define ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY 1
-#  else
-#    define ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY 0
-#  endif
-#endif
-
-/**
- * ZSTD_window_canOverflowCorrect():
- * Returns non-zero if the indices are large enough for overflow correction
- * to work correctly without impacting compression ratio.
- */
-MEM_STATIC U32 ZSTD_window_canOverflowCorrect(ZSTD_window_t const window,
-                                              U32 cycleLog,
-                                              U32 maxDist,
-                                              U32 loadedDictEnd,
-                                              void const* src)
-{
-    U32 const cycleSize = 1u << cycleLog;
-    U32 const curr = (U32)((BYTE const*)src - window.base);
-    U32 const minIndexToOverflowCorrect = cycleSize + MAX(maxDist, cycleSize);
-
-    /* Adjust the min index to backoff the overflow correction frequency,
-     * so we don't waste too much CPU in overflow correction. If this
-     * computation overflows we don't really care, we just need to make
-     * sure it is at least minIndexToOverflowCorrect.
-     */
-    U32 const adjustment = window.nbOverflowCorrections + 1;
-    U32 const adjustedIndex = MAX(minIndexToOverflowCorrect * adjustment,
-                                  minIndexToOverflowCorrect);
-    U32 const indexLargeEnough = curr > adjustedIndex;
-
-    /* Only overflow correct early if the dictionary is invalidated already,
-     * so we don't hurt compression ratio.
-     */
-    U32 const dictionaryInvalidated = curr > maxDist + loadedDictEnd;
-
-    return indexLargeEnough && dictionaryInvalidated;
-}
-
 /**
  * ZSTD_window_needOverflowCorrection():
  * Returns non-zero if the indices are getting too large and need overflow
  * protection.
  */
 MEM_STATIC U32 ZSTD_window_needOverflowCorrection(ZSTD_window_t const window,
-                                                  U32 cycleLog,
-                                                  U32 maxDist,
-                                                  U32 loadedDictEnd,
-                                                  void const* src,
                                                   void const* srcEnd)
 {
     U32 const curr = (U32)((BYTE const*)srcEnd - window.base);
-    if (ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY) {
-        if (ZSTD_window_canOverflowCorrect(window, cycleLog, maxDist, loadedDictEnd, src)) {
-            return 1;
-        }
-    }
     return curr > ZSTD_CURRENT_MAX;
 }
 
@@ -986,6 +853,7 @@ MEM_STATIC U32 ZSTD_window_needOverflowCorrection(ZSTD_window_t const window,
  *
  * The least significant cycleLog bits of the indices must remain the same,
  * which may be 0. Every index up to maxDist in the past must be valid.
+ * NOTE: (maxDist & cycleMask) must be zero.
  */
 MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
                                            U32 maxDist, void const* src)
@@ -1009,25 +877,17 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
      * 3. (cctx->lowLimit + 1<<windowLog) < 1<<32:
      *    windowLog <= 31 ==> 3<<29 + 1<<windowLog < 7<<29 < 1<<32.
      */
-    U32 const cycleSize = 1u << cycleLog;
-    U32 const cycleMask = cycleSize - 1;
+    U32 const cycleMask = (1U << cycleLog) - 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 currentCycle1 = currentCycle0 == 0 ? (1U << cycleLog) : currentCycle0;
+    U32 const newCurrent = currentCycle1 + maxDist;
     U32 const correction = curr - newCurrent;
-    /* maxDist must be a power of two so that:
-     *   (newCurrent & cycleMask) == (curr & cycleMask)
-     * This is required to not corrupt the chains / binary tree.
-     */
-    assert((maxDist & (maxDist - 1)) == 0);
-    assert((curr & cycleMask) == (newCurrent & cycleMask));
+    assert((maxDist & cycleMask) == 0);
     assert(curr > newCurrent);
-    if (!ZSTD_WINDOW_OVERFLOW_CORRECT_FREQUENTLY) {
-        /* Loose bound, should be around 1<<29 (see above) */
-        assert(correction > 1<<28);
-    }
+    /* Loose bound, should be around 1<<29 (see above) */
+    assert(correction > 1<<28);
 
     window->base += correction;
     window->dictBase += correction;
@@ -1043,8 +903,6 @@ MEM_STATIC U32 ZSTD_window_correctOverflow(ZSTD_window_t* window, U32 cycleLog,
     assert(window->lowLimit <= newCurrent);
     assert(window->dictLimit <= newCurrent);
 
-    ++window->nbOverflowCorrections;
-
     DEBUGLOG(4, "Correction of 0x%x bytes to lowLimit=0x%x", correction,
              window->lowLimit);
     return correction;
@@ -1154,7 +1012,6 @@ MEM_STATIC void ZSTD_window_init(ZSTD_window_t* window) {
     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->nbOverflowCorrections = 0;
 }
 
 /**
@@ -1165,8 +1022,7 @@ MEM_STATIC void ZSTD_window_init(ZSTD_window_t* window) {
  * Returns non-zero if the segment is contiguous.
  */
 MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
-                                  void const* src, size_t srcSize,
-                                  int forceNonContiguous)
+                                  void const* src, size_t srcSize)
 {
     BYTE const* const ip = (BYTE const*)src;
     U32 contiguous = 1;
@@ -1176,7 +1032,7 @@ MEM_STATIC U32 ZSTD_window_update(ZSTD_window_t* window,
     assert(window->base != NULL);
     assert(window->dictBase != NULL);
     /* Check if blocks follow each other */
-    if (src != window->nextSrc || forceNonContiguous) {
+    if (src != window->nextSrc) {
         /* not contiguous */
         size_t const distanceFromBase = (size_t)(window->nextSrc - window->base);
         DEBUGLOG(5, "Non contiguous blocks, new segment starts at %u", window->dictLimit);

lib/compress/zstd_compress_literals.c

@@ -117,7 +117,7 @@ size_t ZSTD_compressLiterals (ZSTD_hufCTables_t const* prevHuf,
         }
     }
 
-    if ((cLitSize==0) || (cLitSize >= srcSize - minGain) || ERR_isError(cLitSize)) {
+    if ((cLitSize==0) | (cLitSize >= srcSize - minGain) | ERR_isError(cLitSize)) {
         ZSTD_memcpy(nextHuf, prevHuf, sizeof(*prevHuf));
         return ZSTD_noCompressLiterals(dst, dstCapacity, src, srcSize);
     }

lib/compress/zstd_compress_sequences.c

@@ -85,8 +85,6 @@ static size_t ZSTD_entropyCost(unsigned const* count, unsigned const max, size_t
 {
     unsigned cost = 0;
     unsigned s;
-
-    assert(total > 0);
     for (s = 0; s <= max; ++s) {
         unsigned norm = (unsigned)((256 * count[s]) / total);
         if (count[s] != 0 && norm == 0)

lib/compress/zstd_compress_superblock.c

@@ -15,10 +15,289 @@
 
 #include "../common/zstd_internal.h"  /* ZSTD_getSequenceLength */
 #include "hist.h"                     /* HIST_countFast_wksp */
-#include "zstd_compress_internal.h"   /* ZSTD_[huf|fse|entropy]CTablesMetadata_t */
+#include "zstd_compress_internal.h"
 #include "zstd_compress_sequences.h"
 #include "zstd_compress_literals.h"
 
+/*-*************************************
+*  Superblock entropy buffer structs
+***************************************/
+/** ZSTD_hufCTablesMetadata_t :
+ *  Stores Literals Block Type for a super-block in hType, and
+ *  huffman tree description in hufDesBuffer.
+ *  hufDesSize refers to the size of huffman tree description in bytes.
+ *  This metadata is populated in ZSTD_buildSuperBlockEntropy_literal() */
+typedef struct {
+    symbolEncodingType_e hType;
+    BYTE hufDesBuffer[ZSTD_MAX_HUF_HEADER_SIZE];
+    size_t hufDesSize;
+} ZSTD_hufCTablesMetadata_t;
+
+/** ZSTD_fseCTablesMetadata_t :
+ *  Stores symbol compression modes for a super-block in {ll, ol, ml}Type, and
+ *  fse tables in fseTablesBuffer.
+ *  fseTablesSize refers to the size of fse tables in bytes.
+ *  This metadata is populated in ZSTD_buildSuperBlockEntropy_sequences() */
+typedef struct {
+    symbolEncodingType_e llType;
+    symbolEncodingType_e ofType;
+    symbolEncodingType_e mlType;
+    BYTE fseTablesBuffer[ZSTD_MAX_FSE_HEADERS_SIZE];
+    size_t fseTablesSize;
+    size_t lastCountSize; /* This is to account for bug in 1.3.4. More detail in ZSTD_compressSubBlock_sequences() */
+} ZSTD_fseCTablesMetadata_t;
+
+typedef struct {
+    ZSTD_hufCTablesMetadata_t hufMetadata;
+    ZSTD_fseCTablesMetadata_t fseMetadata;
+} ZSTD_entropyCTablesMetadata_t;
+
+
+/** ZSTD_buildSuperBlockEntropy_literal() :
+ *  Builds entropy for the super-block literals.
+ *  Stores literals block type (raw, rle, compressed, repeat) and
+ *  huffman description table to hufMetadata.
+ *  @return : size of huffman description table or error code */
+static size_t ZSTD_buildSuperBlockEntropy_literal(void* const src, size_t srcSize,
+                                            const ZSTD_hufCTables_t* prevHuf,
+                                                  ZSTD_hufCTables_t* nextHuf,
+                                                  ZSTD_hufCTablesMetadata_t* hufMetadata,
+                                                  const int disableLiteralsCompression,
+                                                  void* workspace, size_t wkspSize)
+{
+    BYTE* const wkspStart = (BYTE*)workspace;
+    BYTE* const wkspEnd = wkspStart + wkspSize;
+    BYTE* const countWkspStart = wkspStart;
+    unsigned* const countWksp = (unsigned*)workspace;
+    const size_t countWkspSize = (HUF_SYMBOLVALUE_MAX + 1) * sizeof(unsigned);
+    BYTE* const nodeWksp = countWkspStart + countWkspSize;
+    const size_t nodeWkspSize = wkspEnd-nodeWksp;
+    unsigned maxSymbolValue = 255;
+    unsigned huffLog = HUF_TABLELOG_DEFAULT;
+    HUF_repeat repeat = prevHuf->repeatMode;
+
+    DEBUGLOG(5, "ZSTD_buildSuperBlockEntropy_literal (srcSize=%zu)", srcSize);
+
+    /* Prepare nextEntropy assuming reusing the existing table */
+    ZSTD_memcpy(nextHuf, prevHuf, sizeof(*prevHuf));
+
+    if (disableLiteralsCompression) {
+        DEBUGLOG(5, "set_basic - disabled");
+        hufMetadata->hType = set_basic;
+        return 0;
+    }
+
+    /* small ? don't even attempt compression (speed opt) */
+#   define COMPRESS_LITERALS_SIZE_MIN 63
+    {   size_t const minLitSize = (prevHuf->repeatMode == HUF_repeat_valid) ? 6 : COMPRESS_LITERALS_SIZE_MIN;
+        if (srcSize <= minLitSize) {
+            DEBUGLOG(5, "set_basic - too small");
+            hufMetadata->hType = set_basic;
+            return 0;
+        }
+    }
+
+    /* Scan input and build symbol stats */
+    {   size_t const largest = HIST_count_wksp (countWksp, &maxSymbolValue, (const BYTE*)src, srcSize, workspace, wkspSize);
+        FORWARD_IF_ERROR(largest, "HIST_count_wksp failed");
+        if (largest == srcSize) {
+            DEBUGLOG(5, "set_rle");
+            hufMetadata->hType = set_rle;
+            return 0;
+        }
+        if (largest <= (srcSize >> 7)+4) {
+            DEBUGLOG(5, "set_basic - no gain");
+            hufMetadata->hType = set_basic;
+            return 0;
+        }
+    }
+
+    /* Validate the previous Huffman table */
+    if (repeat == HUF_repeat_check && !HUF_validateCTable((HUF_CElt const*)prevHuf->CTable, countWksp, maxSymbolValue)) {
+        repeat = HUF_repeat_none;
+    }
+
+    /* Build Huffman Tree */
+    ZSTD_memset(nextHuf->CTable, 0, sizeof(nextHuf->CTable));
+    huffLog = HUF_optimalTableLog(huffLog, srcSize, maxSymbolValue);
+    {   size_t const maxBits = HUF_buildCTable_wksp((HUF_CElt*)nextHuf->CTable, countWksp,
+                                                    maxSymbolValue, huffLog,
+                                                    nodeWksp, nodeWkspSize);
+        FORWARD_IF_ERROR(maxBits, "HUF_buildCTable_wksp");
+        huffLog = (U32)maxBits;
+        {   /* Build and write the CTable */
+            size_t const newCSize = HUF_estimateCompressedSize(
+                    (HUF_CElt*)nextHuf->CTable, countWksp, maxSymbolValue);
+            size_t const hSize = HUF_writeCTable_wksp(
+                    hufMetadata->hufDesBuffer, sizeof(hufMetadata->hufDesBuffer),
+                    (HUF_CElt*)nextHuf->CTable, maxSymbolValue, huffLog,
+                    nodeWksp, nodeWkspSize);
+            /* Check against repeating the previous CTable */
+            if (repeat != HUF_repeat_none) {
+                size_t const oldCSize = HUF_estimateCompressedSize(
+                        (HUF_CElt const*)prevHuf->CTable, countWksp, maxSymbolValue);
+                if (oldCSize < srcSize && (oldCSize <= hSize + newCSize || hSize + 12 >= srcSize)) {
+                    DEBUGLOG(5, "set_repeat - smaller");
+                    ZSTD_memcpy(nextHuf, prevHuf, sizeof(*prevHuf));
+                    hufMetadata->hType = set_repeat;
+                    return 0;
+                }
+            }
+            if (newCSize + hSize >= srcSize) {
+                DEBUGLOG(5, "set_basic - no gains");
+                ZSTD_memcpy(nextHuf, prevHuf, sizeof(*prevHuf));
+                hufMetadata->hType = set_basic;
+                return 0;
+            }
+            DEBUGLOG(5, "set_compressed (hSize=%u)", (U32)hSize);
+            hufMetadata->hType = set_compressed;
+            nextHuf->repeatMode = HUF_repeat_check;
+            return hSize;
+        }
+    }
+}
+
+/** ZSTD_buildSuperBlockEntropy_sequences() :
+ *  Builds entropy for the super-block sequences.
+ *  Stores symbol compression modes and fse table to fseMetadata.
+ *  @return : size of fse tables or error code */
+static size_t ZSTD_buildSuperBlockEntropy_sequences(seqStore_t* seqStorePtr,
+                                              const ZSTD_fseCTables_t* prevEntropy,
+                                                    ZSTD_fseCTables_t* nextEntropy,
+                                              const ZSTD_CCtx_params* cctxParams,
+                                                    ZSTD_fseCTablesMetadata_t* fseMetadata,
+                                                    void* workspace, size_t wkspSize)
+{
+    BYTE* const wkspStart = (BYTE*)workspace;
+    BYTE* const wkspEnd = wkspStart + wkspSize;
+    BYTE* const countWkspStart = wkspStart;
+    unsigned* const countWksp = (unsigned*)workspace;
+    const size_t countWkspSize = (MaxSeq + 1) * sizeof(unsigned);
+    BYTE* const cTableWksp = countWkspStart + countWkspSize;
+    const size_t cTableWkspSize = wkspEnd-cTableWksp;
+    ZSTD_strategy const strategy = cctxParams->cParams.strategy;
+    FSE_CTable* CTable_LitLength = nextEntropy->litlengthCTable;
+    FSE_CTable* CTable_OffsetBits = nextEntropy->offcodeCTable;
+    FSE_CTable* CTable_MatchLength = nextEntropy->matchlengthCTable;
+    const BYTE* const ofCodeTable = seqStorePtr->ofCode;
+    const BYTE* const llCodeTable = seqStorePtr->llCode;
+    const BYTE* const mlCodeTable = seqStorePtr->mlCode;
+    size_t const nbSeq = seqStorePtr->sequences - seqStorePtr->sequencesStart;
+    BYTE* const ostart = fseMetadata->fseTablesBuffer;
+    BYTE* const oend = ostart + sizeof(fseMetadata->fseTablesBuffer);
+    BYTE* op = ostart;
+
+    assert(cTableWkspSize >= (1 << MaxFSELog) * sizeof(FSE_FUNCTION_TYPE));
+    DEBUGLOG(5, "ZSTD_buildSuperBlockEntropy_sequences (nbSeq=%zu)", nbSeq);
+    ZSTD_memset(workspace, 0, wkspSize);
+
+    fseMetadata->lastCountSize = 0;
+    /* convert length/distances into codes */
+    ZSTD_seqToCodes(seqStorePtr);
+    /* build CTable for Literal Lengths */
+    {   U32 LLtype;
+        unsigned max = MaxLL;
+        size_t const mostFrequent = HIST_countFast_wksp(countWksp, &max, llCodeTable, nbSeq, workspace, wkspSize);  /* can't fail */
+        DEBUGLOG(5, "Building LL table");
+        nextEntropy->litlength_repeatMode = prevEntropy->litlength_repeatMode;
+        LLtype = ZSTD_selectEncodingType(&nextEntropy->litlength_repeatMode,
+                                        countWksp, max, mostFrequent, nbSeq,
+                                        LLFSELog, prevEntropy->litlengthCTable,
+                                        LL_defaultNorm, LL_defaultNormLog,
+                                        ZSTD_defaultAllowed, strategy);
+        assert(set_basic < set_compressed && set_rle < set_compressed);
+        assert(!(LLtype < set_compressed && nextEntropy->litlength_repeatMode != FSE_repeat_none)); /* We don't copy tables */
+        {   size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_LitLength, LLFSELog, (symbolEncodingType_e)LLtype,
+                                                    countWksp, max, llCodeTable, nbSeq, LL_defaultNorm, LL_defaultNormLog, MaxLL,
+                                                    prevEntropy->litlengthCTable, sizeof(prevEntropy->litlengthCTable),
+                                                    cTableWksp, cTableWkspSize);
+            FORWARD_IF_ERROR(countSize, "ZSTD_buildCTable for LitLens failed");
+            if (LLtype == set_compressed)
+                fseMetadata->lastCountSize = countSize;
+            op += countSize;
+            fseMetadata->llType = (symbolEncodingType_e) LLtype;
+    }   }
+    /* build CTable for Offsets */
+    {   U32 Offtype;
+        unsigned max = MaxOff;
+        size_t const mostFrequent = HIST_countFast_wksp(countWksp, &max, ofCodeTable, nbSeq, workspace, wkspSize);  /* can't fail */
+        /* We can only use the basic table if max <= DefaultMaxOff, otherwise the offsets are too large */
+        ZSTD_defaultPolicy_e const defaultPolicy = (max <= DefaultMaxOff) ? ZSTD_defaultAllowed : ZSTD_defaultDisallowed;
+        DEBUGLOG(5, "Building OF table");
+        nextEntropy->offcode_repeatMode = prevEntropy->offcode_repeatMode;
+        Offtype = ZSTD_selectEncodingType(&nextEntropy->offcode_repeatMode,
+                                        countWksp, max, mostFrequent, nbSeq,
+                                        OffFSELog, prevEntropy->offcodeCTable,
+                                        OF_defaultNorm, OF_defaultNormLog,
+                                        defaultPolicy, strategy);
+        assert(!(Offtype < set_compressed && nextEntropy->offcode_repeatMode != FSE_repeat_none)); /* We don't copy tables */
+        {   size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_OffsetBits, OffFSELog, (symbolEncodingType_e)Offtype,
+                                                    countWksp, max, ofCodeTable, nbSeq, OF_defaultNorm, OF_defaultNormLog, DefaultMaxOff,
+                                                    prevEntropy->offcodeCTable, sizeof(prevEntropy->offcodeCTable),
+                                                    cTableWksp, cTableWkspSize);
+            FORWARD_IF_ERROR(countSize, "ZSTD_buildCTable for Offsets failed");
+            if (Offtype == set_compressed)
+                fseMetadata->lastCountSize = countSize;
+            op += countSize;
+            fseMetadata->ofType = (symbolEncodingType_e) Offtype;
+    }   }
+    /* build CTable for MatchLengths */
+    {   U32 MLtype;
+        unsigned max = MaxML;
+        size_t const mostFrequent = HIST_countFast_wksp(countWksp, &max, mlCodeTable, nbSeq, workspace, wkspSize);   /* can't fail */
+        DEBUGLOG(5, "Building ML table (remaining space : %i)", (int)(oend-op));
+        nextEntropy->matchlength_repeatMode = prevEntropy->matchlength_repeatMode;
+        MLtype = ZSTD_selectEncodingType(&nextEntropy->matchlength_repeatMode,
+                                        countWksp, max, mostFrequent, nbSeq,
+                                        MLFSELog, prevEntropy->matchlengthCTable,
+                                        ML_defaultNorm, ML_defaultNormLog,
+                                        ZSTD_defaultAllowed, strategy);
+        assert(!(MLtype < set_compressed && nextEntropy->matchlength_repeatMode != FSE_repeat_none)); /* We don't copy tables */
+        {   size_t const countSize = ZSTD_buildCTable(op, oend - op, CTable_MatchLength, MLFSELog, (symbolEncodingType_e)MLtype,
+                                                    countWksp, max, mlCodeTable, nbSeq, ML_defaultNorm, ML_defaultNormLog, MaxML,
+                                                    prevEntropy->matchlengthCTable, sizeof(prevEntropy->matchlengthCTable),
+                                                    cTableWksp, cTableWkspSize);
+            FORWARD_IF_ERROR(countSize, "ZSTD_buildCTable for MatchLengths failed");
+            if (MLtype == set_compressed)
+                fseMetadata->lastCountSize = countSize;
+            op += countSize;
+            fseMetadata->mlType = (symbolEncodingType_e) MLtype;
+    }   }
+    assert((size_t) (op-ostart) <= sizeof(fseMetadata->fseTablesBuffer));
+    return op-ostart;
+}
+
+
+/** ZSTD_buildSuperBlockEntropy() :
+ *  Builds entropy for the super-block.
+ *  @return : 0 on success or error code */
+static size_t
+ZSTD_buildSuperBlockEntropy(seqStore_t* seqStorePtr,
+                      const ZSTD_entropyCTables_t* prevEntropy,
+                            ZSTD_entropyCTables_t* nextEntropy,
+                      const ZSTD_CCtx_params* cctxParams,
+                            ZSTD_entropyCTablesMetadata_t* entropyMetadata,
+                            void* workspace, size_t wkspSize)
+{
+    size_t const litSize = seqStorePtr->lit - seqStorePtr->litStart;
+    DEBUGLOG(5, "ZSTD_buildSuperBlockEntropy");
+    entropyMetadata->hufMetadata.hufDesSize =
+        ZSTD_buildSuperBlockEntropy_literal(seqStorePtr->litStart, litSize,
+                                            &prevEntropy->huf, &nextEntropy->huf,
+                                            &entropyMetadata->hufMetadata,
+                                            ZSTD_disableLiteralsCompression(cctxParams),
+                                            workspace, wkspSize);
+    FORWARD_IF_ERROR(entropyMetadata->hufMetadata.hufDesSize, "ZSTD_buildSuperBlockEntropy_literal failed");
+    entropyMetadata->fseMetadata.fseTablesSize =
+        ZSTD_buildSuperBlockEntropy_sequences(seqStorePtr,
+                                              &prevEntropy->fse, &nextEntropy->fse,
+                                              cctxParams,
+                                              &entropyMetadata->fseMetadata,
+                                              workspace, wkspSize);
+    FORWARD_IF_ERROR(entropyMetadata->fseMetadata.fseTablesSize, "ZSTD_buildSuperBlockEntropy_sequences failed");
+    return 0;
+}
+
 /** ZSTD_compressSubBlock_literal() :
  *  Compresses literals section for a sub-block.
  *  When we have to write the Huffman table we will sometimes choose a header
@@ -132,6 +411,8 @@ static size_t ZSTD_seqDecompressedSize(seqStore_t const* seqStore, const seqDef*
     const seqDef* sp = sstart;
     size_t matchLengthSum = 0;
     size_t litLengthSum = 0;
+    /* Only used by assert(), suppress unused variable warnings in production. */
+    (void)litLengthSum;
     while (send-sp > 0) {
         ZSTD_sequenceLength const seqLen = ZSTD_getSequenceLength(seqStore, sp);
         litLengthSum += seqLen.litLength;
@@ -365,9 +646,8 @@ static size_t ZSTD_estimateSubBlockSize_sequences(const BYTE* ofCodeTable,
                                                   void* workspace, size_t wkspSize,
                                                   int writeEntropy)
 {
-    size_t const sequencesSectionHeaderSize = 3; /* Use hard coded size of 3 bytes */
+    size_t sequencesSectionHeaderSize = 3; /* Use hard coded size of 3 bytes */
     size_t cSeqSizeEstimate = 0;
-    if (nbSeq == 0) return sequencesSectionHeaderSize;
     cSeqSizeEstimate += ZSTD_estimateSubBlockSize_symbolType(fseMetadata->ofType, ofCodeTable, MaxOff,
                                          nbSeq, fseTables->offcodeCTable, NULL,
                                          OF_defaultNorm, OF_defaultNormLog, DefaultMaxOff,
@@ -553,7 +833,7 @@ size_t ZSTD_compressSuperBlock(ZSTD_CCtx* zc,
                                unsigned lastBlock) {
     ZSTD_entropyCTablesMetadata_t entropyMetadata;
 
-    FORWARD_IF_ERROR(ZSTD_buildBlockEntropyStats(&zc->seqStore,
+    FORWARD_IF_ERROR(ZSTD_buildSuperBlockEntropy(&zc->seqStore,
           &zc->blockState.prevCBlock->entropy,
           &zc->blockState.nextCBlock->entropy,
           &zc->appliedParams,

lib/compress/zstd_cwksp.h

@@ -35,10 +35,6 @@ extern "C" {
 #define ZSTD_CWKSP_ASAN_REDZONE_SIZE 128
 #endif
 
-
-/* Set our tables and aligneds to align by 64 bytes */
-#define ZSTD_CWKSP_ALIGNMENT_BYTES 64
-
 /*-*************************************
 *  Structures
 ***************************************/
@@ -121,11 +117,10 @@ typedef enum {
  * - Tables: these are any of several different datastructures (hash tables,
  *   chain tables, binary trees) that all respect a common format: they are
  *   uint32_t arrays, all of whose values are between 0 and (nextSrc - base).
- *   Their sizes depend on the cparams. These tables are 64-byte aligned.
+ *   Their sizes depend on the cparams.
  *
  * - Aligned: these buffers are used for various purposes that require 4 byte
- *   alignment, but don't require any initialization before they're used. These
- *   buffers are each aligned to 64 bytes.
+ *   alignment, but don't require any initialization before they're used.
  *
  * - Buffers: these buffers are used for various purposes that don't require
  *   any alignment or initialization before they're used. This means they can
@@ -138,7 +133,8 @@ typedef enum {
  *
  * 1. Objects
  * 2. Buffers
- * 3. Aligned/Tables
+ * 3. Aligned
+ * 4. Tables
  *
  * Attempts to reserve objects of different types out of order will fail.
  */
@@ -191,8 +187,6 @@ MEM_STATIC size_t ZSTD_cwksp_align(size_t size, size_t const align) {
  * Since tables aren't currently redzoned, you don't need to call through this
  * to figure out how much space you need for the matchState tables. Everything
  * else is though.
- *
- * Do not use for sizing aligned buffers. Instead, use ZSTD_cwksp_aligned_alloc_size().
  */
 MEM_STATIC size_t ZSTD_cwksp_alloc_size(size_t size) {
     if (size == 0)
@@ -204,110 +198,30 @@ MEM_STATIC size_t ZSTD_cwksp_alloc_size(size_t size) {
 #endif
 }
 
-/**
- * Returns an adjusted alloc size that is the nearest larger multiple of 64 bytes.
- * Used to determine the number of bytes required for a given "aligned".
- */
-MEM_STATIC size_t ZSTD_cwksp_aligned_alloc_size(size_t size) {
-    return ZSTD_cwksp_alloc_size(ZSTD_cwksp_align(size, ZSTD_CWKSP_ALIGNMENT_BYTES));
-}
-
-/**
- * Returns the amount of additional space the cwksp must allocate
- * for internal purposes (currently only alignment).
- */
-MEM_STATIC size_t ZSTD_cwksp_slack_space_required(void) {
-    /* For alignment, the wksp will always allocate an additional n_1=[1, 64] bytes
-     * to align the beginning of tables section, as well as another n_2=[0, 63] bytes
-     * to align the beginning of the aligned secion.
-     *
-     * n_1 + n_2 == 64 bytes if the cwksp is freshly allocated, due to tables and
-     * aligneds being sized in multiples of 64 bytes.
-     */
-    size_t const slackSpace = ZSTD_CWKSP_ALIGNMENT_BYTES;
-    return slackSpace;
-}
-
-
-/**
- * Return the number of additional bytes required to align a pointer to the given number of bytes.
- * alignBytes must be a power of two.
- */
-MEM_STATIC size_t ZSTD_cwksp_bytes_to_align_ptr(void* ptr, const size_t alignBytes) {
-    size_t const alignBytesMask = alignBytes - 1;
-    size_t const bytes = (alignBytes - ((size_t)ptr & (alignBytesMask))) & alignBytesMask;
-    assert((alignBytes & alignBytesMask) == 0);
-    assert(bytes != ZSTD_CWKSP_ALIGNMENT_BYTES);
-    return bytes;
-}
-
-/**
- * Internal function. Do not use directly.
- * Reserves the given number of bytes within the aligned/buffer segment of the wksp, which
- * counts from the end of the wksp. (as opposed to the object/table segment)
- *
- * Returns a pointer to the beginning of that space.
- */
-MEM_STATIC void* ZSTD_cwksp_reserve_internal_buffer_space(ZSTD_cwksp* ws, size_t const bytes) {
-    void* const alloc = (BYTE*)ws->allocStart - bytes;
-    void* const bottom = ws->tableEnd;
-    DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining",
-        alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
-    ZSTD_cwksp_assert_internal_consistency(ws);
-    assert(alloc >= bottom);
-    if (alloc < bottom) {
-        DEBUGLOG(4, "cwksp: alloc failed!");
-        ws->allocFailed = 1;
-        return NULL;
-    }
-    if (alloc < ws->tableValidEnd) {
-        ws->tableValidEnd = alloc;
-    }
-    ws->allocStart = alloc;
-    return alloc;
-}
-
-/**
- * Moves the cwksp to the next phase, and does any necessary allocations.
- * Returns a 0 on success, or zstd error
- */
-MEM_STATIC size_t ZSTD_cwksp_internal_advance_phase(
+MEM_STATIC void ZSTD_cwksp_internal_advance_phase(
         ZSTD_cwksp* ws, ZSTD_cwksp_alloc_phase_e phase) {
     assert(phase >= ws->phase);
     if (phase > ws->phase) {
-        /* Going from allocating objects to allocating buffers */
         if (ws->phase < ZSTD_cwksp_alloc_buffers &&
                 phase >= ZSTD_cwksp_alloc_buffers) {
             ws->tableValidEnd = ws->objectEnd;
         }
-
-        /* Going from allocating buffers to allocating aligneds/tables */
         if (ws->phase < ZSTD_cwksp_alloc_aligned &&
                 phase >= ZSTD_cwksp_alloc_aligned) {
-            {   /* Align the start of the "aligned" to 64 bytes. Use [1, 64] bytes. */
-                size_t const bytesToAlign =
-                    ZSTD_CWKSP_ALIGNMENT_BYTES - ZSTD_cwksp_bytes_to_align_ptr(ws->allocStart, ZSTD_CWKSP_ALIGNMENT_BYTES);
-                DEBUGLOG(5, "reserving aligned alignment addtl space: %zu", bytesToAlign);
-                ZSTD_STATIC_ASSERT((ZSTD_CWKSP_ALIGNMENT_BYTES & (ZSTD_CWKSP_ALIGNMENT_BYTES - 1)) == 0); /* power of 2 */
-                RETURN_ERROR_IF(!ZSTD_cwksp_reserve_internal_buffer_space(ws, bytesToAlign),
-                                memory_allocation, "aligned phase - alignment initial allocation failed!");
-            }
-            {   /* Align the start of the tables to 64 bytes. Use [0, 63] bytes */
-                void* const alloc = ws->objectEnd;
-                size_t const bytesToAlign = ZSTD_cwksp_bytes_to_align_ptr(alloc, ZSTD_CWKSP_ALIGNMENT_BYTES);
-                void* const end = (BYTE*)alloc + bytesToAlign;
-                DEBUGLOG(5, "reserving table alignment addtl space: %zu", bytesToAlign);
-                RETURN_ERROR_IF(end > ws->workspaceEnd, memory_allocation,
-                                "table phase - alignment initial allocation failed!");
-                ws->objectEnd = end;
-                ws->tableEnd = end;
-                ws->tableValidEnd = end;
+            /* If unaligned allocations down from a too-large top have left us
+             * unaligned, we need to realign our alloc ptr. Technically, this
+             * can consume space that is unaccounted for in the neededSpace
+             * calculation. However, I believe this can only happen when the
+             * workspace is too large, and specifically when it is too large
+             * by a larger margin than the space that will be consumed. */
+            /* TODO: cleaner, compiler warning friendly way to do this??? */
+            ws->allocStart = (BYTE*)ws->allocStart - ((size_t)ws->allocStart & (sizeof(U32)-1));
+            if (ws->allocStart < ws->tableValidEnd) {
+                ws->tableValidEnd = ws->allocStart;
             }
         }
         ws->phase = phase;
-        ZSTD_cwksp_assert_internal_consistency(ws);
     }
-    return 0;
 }
 
 /**
@@ -323,25 +237,38 @@ MEM_STATIC int ZSTD_cwksp_owns_buffer(const ZSTD_cwksp* ws, const void* ptr) {
 MEM_STATIC void* ZSTD_cwksp_reserve_internal(
         ZSTD_cwksp* ws, size_t bytes, ZSTD_cwksp_alloc_phase_e phase) {
     void* alloc;
-    if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase)) || bytes == 0) {
+    void* bottom = ws->tableEnd;
+    ZSTD_cwksp_internal_advance_phase(ws, phase);
+    alloc = (BYTE *)ws->allocStart - bytes;
+
+    if (bytes == 0)
         return NULL;
-    }
 
 #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
     /* over-reserve space */
-    bytes += 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
+    alloc = (BYTE *)alloc - 2 * ZSTD_CWKSP_ASAN_REDZONE_SIZE;
 #endif
 
-    alloc = ZSTD_cwksp_reserve_internal_buffer_space(ws, bytes);
+    DEBUGLOG(5, "cwksp: reserving %p %zd bytes, %zd bytes remaining",
+        alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
+    ZSTD_cwksp_assert_internal_consistency(ws);
+    assert(alloc >= bottom);
+    if (alloc < bottom) {
+        DEBUGLOG(4, "cwksp: alloc failed!");
+        ws->allocFailed = 1;
+        return NULL;
+    }
+    if (alloc < ws->tableValidEnd) {
+        ws->tableValidEnd = alloc;
+    }
+    ws->allocStart = alloc;
 
 #if ZSTD_ADDRESS_SANITIZER && !defined (ZSTD_ASAN_DONT_POISON_WORKSPACE)
     /* Move alloc so there's ZSTD_CWKSP_ASAN_REDZONE_SIZE unused space on
      * either size. */
-    if (alloc) {
-        alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE;
-        if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
-            __asan_unpoison_memory_region(alloc, bytes);
-        }
+    alloc = (BYTE *)alloc + ZSTD_CWKSP_ASAN_REDZONE_SIZE;
+    if (ws->isStatic == ZSTD_cwksp_dynamic_alloc) {
+        __asan_unpoison_memory_region(alloc, bytes);
     }
 #endif
 
@@ -356,36 +283,28 @@ MEM_STATIC BYTE* ZSTD_cwksp_reserve_buffer(ZSTD_cwksp* ws, size_t bytes) {
 }
 
 /**
- * Reserves and returns memory sized on and aligned on ZSTD_CWKSP_ALIGNMENT_BYTES (64 bytes).
+ * Reserves and returns memory sized on and aligned on sizeof(unsigned).
  */
 MEM_STATIC void* ZSTD_cwksp_reserve_aligned(ZSTD_cwksp* ws, size_t bytes) {
-    void* ptr = ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, ZSTD_CWKSP_ALIGNMENT_BYTES),
-                                            ZSTD_cwksp_alloc_aligned);
-    assert(((size_t)ptr & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);
-    return ptr;
+    assert((bytes & (sizeof(U32)-1)) == 0);
+    return ZSTD_cwksp_reserve_internal(ws, ZSTD_cwksp_align(bytes, sizeof(U32)), ZSTD_cwksp_alloc_aligned);
 }
 
 /**
- * Aligned on 64 bytes. These buffers have the special property that
+ * Aligned on sizeof(unsigned). These buffers have the special property that
  * their values remain constrained, allowing us to re-use them without
  * memset()-ing them.
  */
 MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes) {
     const ZSTD_cwksp_alloc_phase_e phase = ZSTD_cwksp_alloc_aligned;
-    void* alloc;
-    void* end;
-    void* top;
-
-    if (ZSTD_isError(ZSTD_cwksp_internal_advance_phase(ws, phase))) {
-        return NULL;
-    }
-    alloc = ws->tableEnd;
-    end = (BYTE *)alloc + bytes;
-    top = ws->allocStart;
+    void* alloc = ws->tableEnd;
+    void* end = (BYTE *)alloc + bytes;
+    void* top = ws->allocStart;
 
     DEBUGLOG(5, "cwksp: reserving %p table %zd bytes, %zd bytes remaining",
         alloc, bytes, ZSTD_cwksp_available_space(ws) - bytes);
     assert((bytes & (sizeof(U32)-1)) == 0);
+    ZSTD_cwksp_internal_advance_phase(ws, phase);
     ZSTD_cwksp_assert_internal_consistency(ws);
     assert(end <= top);
     if (end > top) {
@@ -401,8 +320,6 @@ MEM_STATIC void* ZSTD_cwksp_reserve_table(ZSTD_cwksp* ws, size_t bytes) {
     }
 #endif
 
-    assert((bytes & (ZSTD_CWKSP_ALIGNMENT_BYTES-1)) == 0);
-    assert(((size_t)alloc & (ZSTD_CWKSP_ALIGNMENT_BYTES-1))== 0);
     return alloc;
 }
 
@@ -610,24 +527,6 @@ MEM_STATIC int ZSTD_cwksp_reserve_failed(const ZSTD_cwksp* ws) {
 *  Functions Checking Free Space
 ***************************************/
 
-/* ZSTD_alignmentSpaceWithinBounds() :
- * Returns if the estimated space needed for a wksp is within an acceptable limit of the
- * actual amount of space used.
- */
-MEM_STATIC int ZSTD_cwksp_estimated_space_within_bounds(const ZSTD_cwksp* const ws,
-                                                        size_t const estimatedSpace, int resizedWorkspace) {
-    if (resizedWorkspace) {
-        /* Resized/newly allocated wksp should have exact bounds */
-        return ZSTD_cwksp_used(ws) == estimatedSpace;
-    } else {
-        /* Due to alignment, when reusing a workspace, we can actually consume 63 fewer or more bytes
-         * than estimatedSpace. See the comments in zstd_cwksp.h for details.
-         */
-        return (ZSTD_cwksp_used(ws) >= estimatedSpace - 63) && (ZSTD_cwksp_used(ws) <= estimatedSpace + 63);
-    }
-}
-
-
 MEM_STATIC size_t ZSTD_cwksp_available_space(ZSTD_cwksp* ws) {
     return (size_t)((BYTE*)ws->allocStart - (BYTE*)ws->tableEnd);
 }

lib/compress/zstd_double_fast.c

@@ -244,8 +244,6 @@ _search_next_long:
             while (((ip>anchor) & (match>prefixLowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
         }
 
-        /* fall-through */
-
 _match_found:
         offset_2 = offset_1;
         offset_1 = offset;
@@ -409,7 +407,7 @@ static size_t ZSTD_compressBlock_doubleFast_extDict_generic(
         hashSmall[hSmall] = hashLong[hLong] = curr;   /* update hash table */
 
         if ((((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow : ensure repIndex doesn't overlap dict + prefix */
-            & (offset_1 < curr+1 - dictStartIndex)) /* note: we are searching at curr+1 */
+            & (repIndex > dictStartIndex))
           && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
             const BYTE* repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend;
             mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixStart) + 4;
@@ -477,7 +475,7 @@ static size_t ZSTD_compressBlock_doubleFast_extDict_generic(
                 U32 const repIndex2 = current2 - offset_2;
                 const BYTE* repMatch2 = repIndex2 < prefixStartIndex ? dictBase + repIndex2 : base + repIndex2;
                 if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3)   /* intentional overflow : ensure repIndex2 doesn't overlap dict + prefix */
-                    & (offset_2 < current2 - dictStartIndex))
+                    & (repIndex2 > dictStartIndex))
                   && (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
                     const BYTE* const repEnd2 = repIndex2 < prefixStartIndex ? dictEnd : iend;
                     size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixStart) + 4;

lib/compress/zstd_fast.c

@@ -416,9 +416,9 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
         const BYTE* const repMatch = repBase + repIndex;
         hashTable[h] = curr;   /* update hash table */
         DEBUGLOG(7, "offset_1 = %u , curr = %u", offset_1, curr);
+        assert(offset_1 <= curr +1);   /* check repIndex */
 
-        if ( ( ((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow */
-             & (offset_1 < curr+1 - dictStartIndex) ) /* note: we are searching at curr+1 */
+        if ( (((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > dictStartIndex))
            && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
             const BYTE* const repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend;
             size_t const rLength = ZSTD_count_2segments(ip+1 +4, repMatch +4, iend, repMatchEnd, prefixStart) + 4;
@@ -453,7 +453,7 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
                 U32 const current2 = (U32)(ip-base);
                 U32 const repIndex2 = current2 - offset_2;
                 const BYTE* const repMatch2 = repIndex2 < prefixStartIndex ? dictBase + repIndex2 : base + repIndex2;
-                if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) & (offset_2 < curr - dictStartIndex))  /* intentional overflow */
+                if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) & (repIndex2 > dictStartIndex))  /* intentional overflow */
                    && (MEM_read32(repMatch2) == MEM_read32(ip)) ) {
                     const BYTE* const repEnd2 = repIndex2 < prefixStartIndex ? dictEnd : iend;
                     size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixStart) + 4;

lib/compress/zstd_lazy.h

@@ -26,7 +26,6 @@ extern "C" {
 #define ZSTD_LAZY_DDSS_BUCKET_LOG 2
 
 U32 ZSTD_insertAndFindFirstIndex(ZSTD_matchState_t* ms, const BYTE* ip);
-void ZSTD_row_update(ZSTD_matchState_t* const ms, const BYTE* ip);
 
 void ZSTD_dedicatedDictSearch_lazy_loadDictionary(ZSTD_matchState_t* ms, const BYTE* const ip);
 
@@ -44,15 +43,6 @@ size_t ZSTD_compressBlock_lazy(
 size_t ZSTD_compressBlock_greedy(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy2_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_greedy_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
 
 size_t ZSTD_compressBlock_btlazy2_dictMatchState(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
@@ -66,15 +56,6 @@ size_t ZSTD_compressBlock_lazy_dictMatchState(
 size_t ZSTD_compressBlock_greedy_dictMatchState(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy2_dictMatchState_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy_dictMatchState_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_greedy_dictMatchState_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
 
 size_t ZSTD_compressBlock_lazy2_dedicatedDictSearch(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
@@ -85,15 +66,6 @@ size_t ZSTD_compressBlock_lazy_dedicatedDictSearch(
 size_t ZSTD_compressBlock_greedy_dedicatedDictSearch(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy2_dedicatedDictSearch_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy_dedicatedDictSearch_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_greedy_dedicatedDictSearch_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
 
 size_t ZSTD_compressBlock_greedy_extDict(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
@@ -104,19 +76,9 @@ size_t ZSTD_compressBlock_lazy_extDict(
 size_t ZSTD_compressBlock_lazy2_extDict(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_greedy_extDict_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy_extDict_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
-size_t ZSTD_compressBlock_lazy2_extDict_row(
-        ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-        void const* src, size_t srcSize);
 size_t ZSTD_compressBlock_btlazy2_extDict(
         ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
         void const* src, size_t srcSize);
-        
 
 #if defined (__cplusplus)
 }

lib/compress/zstd_ldm.c

@@ -57,33 +57,6 @@ static void ZSTD_ldm_gear_init(ldmRollingHashState_t* state, ldmParams_t const*
     }
 }
 
-/** ZSTD_ldm_gear_reset()
- * Feeds [data, data + minMatchLength) into the hash without registering any
- * splits. This effectively resets the hash state. This is used when skipping
- * over data, either at the beginning of a block, or skipping sections.
- */
-static void ZSTD_ldm_gear_reset(ldmRollingHashState_t* state,
-                                BYTE const* data, size_t minMatchLength)
-{
-    U64 hash = state->rolling;
-    size_t n = 0;
-
-#define GEAR_ITER_ONCE() do {                                  \
-        hash = (hash << 1) + ZSTD_ldm_gearTab[data[n] & 0xff]; \
-        n += 1;                                                \
-    } while (0)
-    while (n + 3 < minMatchLength) {
-        GEAR_ITER_ONCE();
-        GEAR_ITER_ONCE();
-        GEAR_ITER_ONCE();
-        GEAR_ITER_ONCE();
-    }
-    while (n < minMatchLength) {
-        GEAR_ITER_ONCE();
-    }
-#undef GEAR_ITER_ONCE
-}
-
 /** ZSTD_ldm_gear_feed():
  *
  * Registers in the splits array all the split points found in the first
@@ -282,7 +255,7 @@ void ZSTD_ldm_fillHashTable(
     while (ip < iend) {
         size_t hashed;
         unsigned n;
-
+        
         numSplits = 0;
         hashed = ZSTD_ldm_gear_feed(&hashState, ip, iend - ip, splits, &numSplits);
 
@@ -354,8 +327,16 @@ static size_t ZSTD_ldm_generateSequences_internal(
 
     /* Initialize the rolling hash state with the first minMatchLength bytes */
     ZSTD_ldm_gear_init(&hashState, params);
-    ZSTD_ldm_gear_reset(&hashState, ip, minMatchLength);
-    ip += minMatchLength;
+    {
+        size_t n = 0;
+
+        while (n < minMatchLength) {
+            numSplits = 0;
+            n += ZSTD_ldm_gear_feed(&hashState, ip + n, minMatchLength - n,
+                                    splits, &numSplits);
+        }
+        ip += minMatchLength;
+    }
 
     while (ip < ilimit) {
         size_t hashed;
@@ -380,7 +361,6 @@ static size_t ZSTD_ldm_generateSequences_internal(
         for (n = 0; n < numSplits; n++) {
             size_t forwardMatchLength = 0, backwardMatchLength = 0,
                    bestMatchLength = 0, mLength;
-            U32 offset;
             BYTE const* const split = candidates[n].split;
             U32 const checksum = candidates[n].checksum;
             U32 const hash = candidates[n].hash;
@@ -448,9 +428,9 @@ static size_t ZSTD_ldm_generateSequences_internal(
             }
 
             /* Match found */
-            offset = (U32)(split - base) - bestEntry->offset;
             mLength = forwardMatchLength + backwardMatchLength;
             {
+                U32 const offset = (U32)(split - base) - bestEntry->offset;
                 rawSeq* const seq = rawSeqStore->seq + rawSeqStore->size;
 
                 /* Out of sequence storage */
@@ -467,21 +447,6 @@ static size_t ZSTD_ldm_generateSequences_internal(
             ZSTD_ldm_insertEntry(ldmState, hash, newEntry, *params);
 
             anchor = split + forwardMatchLength;
-
-            /* If we find a match that ends after the data that we've hashed
-             * then we have a repeating, overlapping, pattern. E.g. all zeros.
-             * If one repetition of the pattern matches our `stopMask` then all
-             * repetitions will. We don't need to insert them all into out table,
-             * only the first one. So skip over overlapping matches.
-             * This is a major speed boost (20x) for compressing a single byte
-             * repeated, when that byte ends up in the table.
-             */
-            if (anchor > ip + hashed) {
-                ZSTD_ldm_gear_reset(&hashState, anchor - minMatchLength, minMatchLength);
-                /* Continue the outter loop at anchor (ip + hashed == anchor). */
-                ip = anchor - hashed;
-                break;
-            }
         }
 
         ip += hashed;
@@ -535,7 +500,7 @@ size_t ZSTD_ldm_generateSequences(
 
         assert(chunkStart < iend);
         /* 1. Perform overflow correction if necessary. */
-        if (ZSTD_window_needOverflowCorrection(ldmState->window, 0, maxDist, ldmState->loadedDictEnd, chunkStart, chunkEnd)) {
+        if (ZSTD_window_needOverflowCorrection(ldmState->window, chunkEnd)) {
             U32 const ldmHSize = 1U << params->hashLog;
             U32 const correction = ZSTD_window_correctOverflow(
                 &ldmState->window, /* cycleLog */ 0, maxDist, chunkStart);
@@ -657,13 +622,12 @@ void ZSTD_ldm_skipRawSeqStoreBytes(rawSeqStore_t* rawSeqStore, size_t nbBytes) {
 
 size_t ZSTD_ldm_blockCompress(rawSeqStore_t* rawSeqStore,
     ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-    ZSTD_useRowMatchFinderMode_e useRowMatchFinder,
     void const* src, size_t srcSize)
 {
     const ZSTD_compressionParameters* const cParams = &ms->cParams;
     unsigned const minMatch = cParams->minMatch;
     ZSTD_blockCompressor const blockCompressor =
-        ZSTD_selectBlockCompressor(cParams->strategy, useRowMatchFinder, ZSTD_matchState_dictMode(ms));
+        ZSTD_selectBlockCompressor(cParams->strategy, ZSTD_matchState_dictMode(ms));
     /* Input bounds */
     BYTE const* const istart = (BYTE const*)src;
     BYTE const* const iend = istart + srcSize;

lib/compress/zstd_ldm.h

@@ -66,7 +66,6 @@ size_t ZSTD_ldm_generateSequences(
  */
 size_t ZSTD_ldm_blockCompress(rawSeqStore_t* rawSeqStore,
             ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
-            ZSTD_useRowMatchFinderMode_e useRowMatchFinder,
             void const* src, size_t srcSize);
 
 /**

lib/compress/zstd_opt.c

@@ -8,6 +8,20 @@
  * You may select, at your option, one of the above-listed licenses.
  */
 
+/**
+ * Disable inlining for the optimal parser for the kernel build.
+ * It is unlikely to be used in the kernel, and where it is used
+ * latency shouldn't matter because it is very slow to begin with.
+ * We prefer a ~180KB binary size win over faster optimal parsing.
+ *
+ * TODO(https://github.com/facebook/zstd/issues/2862):
+ * Improve the code size of the optimal parser in general, so we
+ * don't need this hack for the kernel build.
+ */
+#ifdef ZSTD_LINUX_KERNEL
+#define ZSTD_NO_INLINE 1
+#endif
+
 #include "zstd_compress_internal.h"
 #include "hist.h"
 #include "zstd_opt.h"
@@ -408,7 +422,7 @@ static U32 ZSTD_insertBt1(
     hashTable[h] = curr;   /* Update Hash Table */
 
     assert(windowLow > 0);
-    while (nbCompares-- && (matchIndex >= windowLow)) {
+    for (; nbCompares && (matchIndex >= windowLow); --nbCompares) {
         U32* const nextPtr = bt + 2*(matchIndex & btMask);
         size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
         assert(matchIndex < curr);
@@ -639,7 +653,7 @@ U32 ZSTD_insertBtAndGetAllMatches (
 
     hashTable[h] = curr;   /* Update Hash Table */
 
-    while (nbCompares-- && (matchIndex >= matchLow)) {
+    for (; nbCompares && (matchIndex >= matchLow); --nbCompares) {
         U32* const nextPtr = bt + 2*(matchIndex & btMask);
         const BYTE* match;
         size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
@@ -692,12 +706,13 @@ U32 ZSTD_insertBtAndGetAllMatches (
 
     *smallerPtr = *largerPtr = 0;
 
+    assert(nbCompares <= (1U << ZSTD_SEARCHLOG_MAX)); /* Check we haven't underflowed. */
     if (dictMode == ZSTD_dictMatchState && nbCompares) {
         size_t const dmsH = ZSTD_hashPtr(ip, dmsHashLog, mls);
         U32 dictMatchIndex = dms->hashTable[dmsH];
         const U32* const dmsBt = dms->chainTable;
         commonLengthSmaller = commonLengthLarger = 0;
-        while (nbCompares-- && (dictMatchIndex > dmsLowLimit)) {
+        for (; nbCompares && (dictMatchIndex > dmsLowLimit); --nbCompares) {
             const U32* const nextPtr = dmsBt + 2*(dictMatchIndex & dmsBtMask);
             size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger);   /* guaranteed minimum nb of common bytes */
             const BYTE* match = dmsBase + dictMatchIndex;

lib/compress/zstdmt_compress.c

@@ -512,7 +512,7 @@ ZSTDMT_serialState_reset(serialState_t* serialState,
         if (dictSize > 0) {
             if (dictContentType == ZSTD_dct_rawContent) {
                 BYTE const* const dictEnd = (const BYTE*)dict + dictSize;
-                ZSTD_window_update(&serialState->ldmState.window, dict, dictSize, /* forceNonContiguous */ 0);
+                ZSTD_window_update(&serialState->ldmState.window, dict, dictSize);
                 ZSTD_ldm_fillHashTable(&serialState->ldmState, (const BYTE*)dict, dictEnd, &params.ldmParams);
                 serialState->ldmState.loadedDictEnd = params.forceWindow ? 0 : (U32)(dictEnd - serialState->ldmState.window.base);
             } else {
@@ -569,7 +569,7 @@ static void ZSTDMT_serialState_update(serialState_t* serialState,
             assert(seqStore.seq != NULL && seqStore.pos == 0 &&
                    seqStore.size == 0 && seqStore.capacity > 0);
             assert(src.size <= serialState->params.jobSize);
-            ZSTD_window_update(&serialState->ldmState.window, src.start, src.size, /* forceNonContiguous */ 0);
+            ZSTD_window_update(&serialState->ldmState.window, src.start, src.size);
             error = ZSTD_ldm_generateSequences(
                 &serialState->ldmState, &seqStore,
                 &serialState->params.ldmParams, src.start, src.size);
@@ -695,10 +695,6 @@ static void ZSTDMT_compressionJob(void* jobDescription)
         {   size_t const forceWindowError = ZSTD_CCtxParams_setParameter(&jobParams, ZSTD_c_forceMaxWindow, !job->firstJob);
             if (ZSTD_isError(forceWindowError)) JOB_ERROR(forceWindowError);
         }
-        if (!job->firstJob) {
-            size_t const err = ZSTD_CCtxParams_setParameter(&jobParams, ZSTD_c_deterministicRefPrefix, 0);
-            if (ZSTD_isError(err)) JOB_ERROR(err);
-        }
         {   size_t const initError = ZSTD_compressBegin_advanced_internal(cctx,
                                         job->prefix.start, job->prefix.size, ZSTD_dct_rawContent, /* load dictionary in "content-only" mode (no header analysis) */
                                         ZSTD_dtlm_fast,
@@ -754,12 +750,6 @@ static void ZSTDMT_compressionJob(void* jobDescription)
             if (ZSTD_isError(cSize)) JOB_ERROR(cSize);
             lastCBlockSize = cSize;
     }   }
-    if (!job->firstJob) {
-        /* Double check that we don't have an ext-dict, because then our
-         * repcode invalidation doesn't work.
-         */
-        assert(!ZSTD_window_hasExtDict(cctx->blockState.matchState.window));
-    }
     ZSTD_CCtx_trace(cctx, 0);
 
 _endJob:
@@ -1250,8 +1240,9 @@ size_t ZSTDMT_initCStream_internal(
 
     if (params.rsyncable) {
         /* Aim for the targetsectionSize as the average job size. */
-        U32 const jobSizeKB = (U32)(mtctx->targetSectionSize >> 10);
-        U32 const rsyncBits = (assert(jobSizeKB >= 1), ZSTD_highbit32(jobSizeKB) + 10);
+        U32 const jobSizeMB = (U32)(mtctx->targetSectionSize >> 20);
+        U32 const rsyncBits = ZSTD_highbit32(jobSizeMB) + 20;
+        assert(jobSizeMB >= 1);
         DEBUGLOG(4, "rsyncLog = %u", rsyncBits);
         mtctx->rsync.hash = 0;
         mtctx->rsync.hitMask = (1ULL << rsyncBits) - 1;

lib/compress/zstdmt_compress.h

@@ -32,11 +32,11 @@
 
 
 /* ===   Constants   === */
-#ifndef ZSTDMT_NBWORKERS_MAX /* a different value can be selected at compile time */
-#  define ZSTDMT_NBWORKERS_MAX ((sizeof(void*)==4) /*32-bit*/ ? 64 : 256)
+#ifndef ZSTDMT_NBWORKERS_MAX
+#  define ZSTDMT_NBWORKERS_MAX 200
 #endif
-#ifndef ZSTDMT_JOBSIZE_MIN   /* a different value can be selected at compile time */
-#  define ZSTDMT_JOBSIZE_MIN (512 KB)
+#ifndef ZSTDMT_JOBSIZE_MIN
+#  define ZSTDMT_JOBSIZE_MIN (1 MB)
 #endif
 #define ZSTDMT_JOBLOG_MAX   (MEM_32bits() ? 29 : 30)
 #define ZSTDMT_JOBSIZE_MAX  (MEM_32bits() ? (512 MB) : (1024 MB))

lib/decompress/huf_decompress.c

@@ -886,7 +886,7 @@ HUF_decompress4X2_usingDTable_internal_body(
             HUF_DECODE_SYMBOLX2_0(op2, &bitD2);
             HUF_DECODE_SYMBOLX2_0(op3, &bitD3);
             HUF_DECODE_SYMBOLX2_0(op4, &bitD4);
-            endSignal = (U32)LIKELY(
+            endSignal = (U32)LIKELY((U32)
                         (BIT_reloadDStreamFast(&bitD1) == BIT_DStream_unfinished)
                       & (BIT_reloadDStreamFast(&bitD2) == BIT_DStream_unfinished)
                       & (BIT_reloadDStreamFast(&bitD3) == BIT_DStream_unfinished)

lib/decompress/zstd_decompress.c

@@ -177,12 +177,15 @@ static const ZSTD_DDict* ZSTD_DDictHashSet_getDDict(ZSTD_DDictHashSet* hashSet,
 static ZSTD_DDictHashSet* ZSTD_createDDictHashSet(ZSTD_customMem customMem) {
     ZSTD_DDictHashSet* ret = (ZSTD_DDictHashSet*)ZSTD_customMalloc(sizeof(ZSTD_DDictHashSet), customMem);
     DEBUGLOG(4, "Allocating new hash set");
+    if (!ret)
+        return NULL;
     ret->ddictPtrTable = (const ZSTD_DDict**)ZSTD_customCalloc(DDICT_HASHSET_TABLE_BASE_SIZE * sizeof(ZSTD_DDict*), customMem);
-    ret->ddictPtrTableSize = DDICT_HASHSET_TABLE_BASE_SIZE;
-    ret->ddictPtrCount = 0;
-    if (!ret || !ret->ddictPtrTable) {
+    if (!ret->ddictPtrTable) {
+        ZSTD_customFree(ret, customMem);
         return NULL;
     }
+    ret->ddictPtrTableSize = DDICT_HASHSET_TABLE_BASE_SIZE;
+    ret->ddictPtrCount = 0;
     return ret;
 }
 
@@ -466,7 +469,9 @@ size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, s
         }
         switch(dictIDSizeCode)
         {
-            default: assert(0);  /* impossible */
+            default:
+                assert(0);  /* impossible */
+                ZSTD_FALLTHROUGH;
             case 0 : break;
             case 1 : dictID = ip[pos]; pos++; break;
             case 2 : dictID = MEM_readLE16(ip+pos); pos+=2; break;
@@ -474,7 +479,9 @@ size_t ZSTD_getFrameHeader_advanced(ZSTD_frameHeader* zfhPtr, const void* src, s
         }
         switch(fcsID)
         {
-            default: assert(0);  /* impossible */
+            default:
+                assert(0);  /* impossible */
+                ZSTD_FALLTHROUGH;
             case 0 : if (singleSegment) frameContentSize = ip[pos]; break;
             case 1 : frameContentSize = MEM_readLE16(ip+pos)+256; break;
             case 2 : frameContentSize = MEM_readLE32(ip+pos); break;
@@ -788,7 +795,7 @@ static size_t ZSTD_setRleBlock(void* dst, size_t dstCapacity,
 static void ZSTD_DCtx_trace_end(ZSTD_DCtx const* dctx, U64 uncompressedSize, U64 compressedSize, unsigned streaming)
 {
 #if ZSTD_TRACE
-    if (dctx->traceCtx && ZSTD_trace_decompress_end != NULL) {
+    if (dctx->traceCtx) {
         ZSTD_Trace trace;
         ZSTD_memset(&trace, 0, sizeof(trace));
         trace.version = ZSTD_VERSION_NUMBER;
@@ -1009,7 +1016,7 @@ static ZSTD_DDict const* ZSTD_getDDict(ZSTD_DCtx* dctx)
     switch (dctx->dictUses) {
     default:
         assert(0 /* Impossible */);
-        /* fall-through */
+        ZSTD_FALLTHROUGH;
     case ZSTD_dont_use:
         ZSTD_clearDict(dctx);
         return NULL;
@@ -1073,7 +1080,9 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     {
     default:   /* should not happen */
         assert(0);
+        ZSTD_FALLTHROUGH;
     case ZSTDds_getFrameHeaderSize:
+        ZSTD_FALLTHROUGH;
     case ZSTDds_decodeFrameHeader:
         return ZSTDnit_frameHeader;
     case ZSTDds_decodeBlockHeader:
@@ -1085,6 +1094,7 @@ ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx* dctx) {
     case ZSTDds_checkChecksum:
         return ZSTDnit_checksum;
     case ZSTDds_decodeSkippableHeader:
+        ZSTD_FALLTHROUGH;
     case ZSTDds_skipFrame:
         return ZSTDnit_skippableFrame;
     }
@@ -1383,7 +1393,7 @@ size_t ZSTD_decompressBegin(ZSTD_DCtx* dctx)
 {
     assert(dctx != NULL);
 #if ZSTD_TRACE
-    dctx->traceCtx = (ZSTD_trace_decompress_begin != NULL) ? ZSTD_trace_decompress_begin(dctx) : 0;
+    dctx->traceCtx = ZSTD_trace_decompress_begin(dctx);
 #endif
     dctx->expected = ZSTD_startingInputLength(dctx->format);  /* dctx->format must be properly set */
     dctx->stage = ZSTDds_getFrameHeaderSize;
@@ -1900,7 +1910,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
             zds->legacyVersion = 0;
             zds->hostageByte = 0;
             zds->expectedOutBuffer = *output;
-            /* fall-through */
+            ZSTD_FALLTHROUGH;
 
         case zdss_loadHeader :
             DEBUGLOG(5, "stage zdss_loadHeader (srcSize : %u)", (U32)(iend - ip));
@@ -2038,7 +2048,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
                         zds->outBuffSize = neededOutBuffSize;
             }   }   }
             zds->streamStage = zdss_read;
-            /* fall-through */
+            ZSTD_FALLTHROUGH;
 
         case zdss_read:
             DEBUGLOG(5, "stage zdss_read");
@@ -2057,7 +2067,7 @@ size_t ZSTD_decompressStream(ZSTD_DStream* zds, ZSTD_outBuffer* output, ZSTD_inB
             }   }
             if (ip==iend) { someMoreWork = 0; break; }   /* no more input */
             zds->streamStage = zdss_load;
-            /* fall-through */
+            ZSTD_FALLTHROUGH;
 
         case zdss_load:
             {   size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds);

lib/decompress/zstd_decompress_block.c

@@ -90,7 +90,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
         case set_repeat:
             DEBUGLOG(5, "set_repeat flag : re-using stats from previous compressed literals block");
             RETURN_ERROR_IF(dctx->litEntropy==0, dictionary_corrupted, "");
-            /* fall-through */
+            ZSTD_FALLTHROUGH;
 
         case set_compressed:
             RETURN_ERROR_IF(srcSize < 5, corruption_detected, "srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3");
@@ -658,6 +658,7 @@ typedef struct {
     size_t litLength;
     size_t matchLength;
     size_t offset;
+    const BYTE* match;
 } seq_t;
 
 typedef struct {
@@ -671,6 +672,9 @@ typedef struct {
     ZSTD_fseState stateOffb;
     ZSTD_fseState stateML;
     size_t prevOffset[ZSTD_REP_NUM];
+    const BYTE* prefixStart;
+    const BYTE* dictEnd;
+    size_t pos;
 } seqState_t;
 
 /*! ZSTD_overlapCopy8() :
@@ -932,9 +936,10 @@ ZSTD_updateFseStateWithDInfo(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, ZSTD
         : 0)
 
 typedef enum { ZSTD_lo_isRegularOffset, ZSTD_lo_isLongOffset=1 } ZSTD_longOffset_e;
+typedef enum { ZSTD_p_noPrefetch=0, ZSTD_p_prefetch=1 } ZSTD_prefetch_e;
 
 FORCE_INLINE_TEMPLATE seq_t
-ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets)
+ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets, const ZSTD_prefetch_e prefetch)
 {
     seq_t seq;
     ZSTD_seqSymbol const llDInfo = seqState->stateLL.table[seqState->stateLL.state];
@@ -1009,6 +1014,14 @@ ZSTD_decodeSequence(seqState_t* seqState, const ZSTD_longOffset_e longOffsets)
     DEBUGLOG(6, "seq: litL=%u, matchL=%u, offset=%u",
                 (U32)seq.litLength, (U32)seq.matchLength, (U32)seq.offset);
 
+    if (prefetch == ZSTD_p_prefetch) {
+        size_t const pos = seqState->pos + seq.litLength;
+        const BYTE* const matchBase = (seq.offset > pos) ? seqState->dictEnd : seqState->prefixStart;
+        seq.match = matchBase + pos - seq.offset;  /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
+                                                    * No consequence though : no memory access will occur, offset is only used for prefetching */
+        seqState->pos = pos + seq.matchLength;
+    }
+
     /* ANS state update
      * gcc-9.0.0 does 2.5% worse with ZSTD_updateFseStateWithDInfo().
      * clang-9.2.0 does 7% worse with ZSTD_updateFseState().
@@ -1109,6 +1122,7 @@ ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
     /* Regen sequences */
     if (nbSeq) {
         seqState_t seqState;
+        size_t error = 0;
         dctx->fseEntropy = 1;
         { U32 i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
         RETURN_ERROR_IF(
@@ -1142,14 +1156,13 @@ ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
          * If you see most cycles served out of the DSB you've hit the good case.
          * If it is pretty even then you may be in an okay case.
          *
-         * This issue has been reproduced on the following CPUs:
+         * I've been able to reproduce this issue on the following CPUs:
          *   - Kabylake: Macbook Pro (15-inch, 2019) 2.4 GHz Intel Core i9
          *               Use Instruments->Counters to get DSB/MITE cycles.
          *               I never got performance swings, but I was able to
          *               go from the good case of mostly DSB to half of the
          *               cycles served from MITE.
          *   - Coffeelake: Intel i9-9900k
-         *   - Coffeelake: Intel i7-9700k
          *
          * I haven't been able to reproduce the instability or DSB misses on any
          * of the following CPUS:
@@ -1162,35 +1175,33 @@ ZSTD_decompressSequences_body( ZSTD_DCtx* dctx,
          *
          *   https://gist.github.com/terrelln/9889fc06a423fd5ca6e99351564473f4
          */
-        __asm__(".p2align 6");
-        __asm__("nop");
         __asm__(".p2align 5");
         __asm__("nop");
-#  if __GNUC__ >= 9
-        /* better for gcc-9 and gcc-10, worse for clang and gcc-8 */
-        __asm__(".p2align 3");
-#  else
         __asm__(".p2align 4");
-#  endif
 #endif
         for ( ; ; ) {
-            seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+            seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_noPrefetch);
             size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, prefixStart, vBase, dictEnd);
 #if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
             assert(!ZSTD_isError(oneSeqSize));
             if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequence, prefixStart, vBase);
 #endif
-            if (UNLIKELY(ZSTD_isError(oneSeqSize)))
-                return oneSeqSize;
             DEBUGLOG(6, "regenerated sequence size : %u", (U32)oneSeqSize);
-            op += oneSeqSize;
-            if (UNLIKELY(!--nbSeq))
-                break;
             BIT_reloadDStream(&(seqState.DStream));
+            op += oneSeqSize;
+            /* gcc and clang both don't like early returns in this loop.
+             * Instead break and check for an error at the end of the loop.
+             */
+            if (UNLIKELY(ZSTD_isError(oneSeqSize))) {
+                error = oneSeqSize;
+                break;
+            }
+            if (UNLIKELY(!--nbSeq)) break;
         }
 
         /* check if reached exact end */
         DEBUGLOG(5, "ZSTD_decompressSequences_body: after decode loop, remaining nbSeq : %i", nbSeq);
+        if (ZSTD_isError(error)) return error;
         RETURN_ERROR_IF(nbSeq, corruption_detected, "");
         RETURN_ERROR_IF(BIT_reloadDStream(&seqState.DStream) < BIT_DStream_completed, corruption_detected, "");
         /* save reps for next block */
@@ -1221,24 +1232,6 @@ ZSTD_decompressSequences_default(ZSTD_DCtx* dctx,
 #endif /* ZSTD_FORCE_DECOMPRESS_SEQUENCES_LONG */
 
 #ifndef ZSTD_FORCE_DECOMPRESS_SEQUENCES_SHORT
-
-FORCE_INLINE_TEMPLATE size_t
-ZSTD_prefetchMatch(size_t prefetchPos, seq_t const sequence,
-                   const BYTE* const prefixStart, const BYTE* const dictEnd)
-{
-    prefetchPos += sequence.litLength;
-    {   const BYTE* const matchBase = (sequence.offset > prefetchPos) ? dictEnd : prefixStart;
-        const BYTE* const match = matchBase + prefetchPos - sequence.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
-                                                                              * No consequence though : memory address is only used for prefetching, not for dereferencing */
-        PREFETCH_L1(match); PREFETCH_L1(match+CACHELINE_SIZE);   /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
-    }
-    return prefetchPos + sequence.matchLength;
-}
-
-/* This decoding function employs prefetching
- * to reduce latency impact of cache misses.
- * It's generally employed when block contains a significant portion of long-distance matches
- * or when coupled with a "cold" dictionary */
 FORCE_INLINE_TEMPLATE size_t
 ZSTD_decompressSequencesLong_body(
                                ZSTD_DCtx* dctx,
@@ -1261,17 +1254,18 @@ ZSTD_decompressSequencesLong_body(
 
     /* Regen sequences */
     if (nbSeq) {
-#define STORED_SEQS 8
+#define STORED_SEQS 4
 #define STORED_SEQS_MASK (STORED_SEQS-1)
-#define ADVANCED_SEQS STORED_SEQS
+#define ADVANCED_SEQS 4
         seq_t sequences[STORED_SEQS];
         int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS);
         seqState_t seqState;
         int seqNb;
-        size_t prefetchPos = (size_t)(op-prefixStart); /* track position relative to prefixStart */
-
         dctx->fseEntropy = 1;
         { int i; for (i=0; i<ZSTD_REP_NUM; i++) seqState.prevOffset[i] = dctx->entropy.rep[i]; }
+        seqState.prefixStart = prefixStart;
+        seqState.pos = (size_t)(op-prefixStart);
+        seqState.dictEnd = dictEnd;
         assert(dst != NULL);
         assert(iend >= ip);
         RETURN_ERROR_IF(
@@ -1283,23 +1277,21 @@ ZSTD_decompressSequencesLong_body(
 
         /* prepare in advance */
         for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && (seqNb<seqAdvance); seqNb++) {
-            seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
-            prefetchPos = ZSTD_prefetchMatch(prefetchPos, sequence, prefixStart, dictEnd);
-            sequences[seqNb] = sequence;
+            sequences[seqNb] = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
+            PREFETCH_L1(sequences[seqNb].match); PREFETCH_L1(sequences[seqNb].match + sequences[seqNb].matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
         }
         RETURN_ERROR_IF(seqNb<seqAdvance, corruption_detected, "");
 
         /* decode and decompress */
         for ( ; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && (seqNb<nbSeq) ; seqNb++) {
-            seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset);
+            seq_t const sequence = ZSTD_decodeSequence(&seqState, isLongOffset, ZSTD_p_prefetch);
             size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], &litPtr, litEnd, prefixStart, dictStart, dictEnd);
 #if defined(FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION) && defined(FUZZING_ASSERT_VALID_SEQUENCE)
             assert(!ZSTD_isError(oneSeqSize));
             if (frame) ZSTD_assertValidSequence(dctx, op, oend, sequences[(seqNb-ADVANCED_SEQS) & STORED_SEQS_MASK], prefixStart, dictStart);
 #endif
             if (ZSTD_isError(oneSeqSize)) return oneSeqSize;
-
-            prefetchPos = ZSTD_prefetchMatch(prefetchPos, sequence, prefixStart, dictEnd);
+            PREFETCH_L1(sequence.match); PREFETCH_L1(sequence.match + sequence.matchLength - 1); /* note : it's safe to invoke PREFETCH() on any memory address, including invalid ones */
             sequences[seqNb & STORED_SEQS_MASK] = sequence;
             op += oneSeqSize;
         }

lib/dictBuilder/cover.c

@@ -26,16 +26,15 @@
 #include <string.h> /* memset */
 #include <time.h>   /* clock */
 
-#ifndef ZDICT_STATIC_LINKING_ONLY
-#  define ZDICT_STATIC_LINKING_ONLY
-#endif
-
 #include "../common/mem.h" /* read */
 #include "../common/pool.h"
 #include "../common/threading.h"
-#include "../common/zstd_internal.h" /* includes zstd.h */
-#include "../zdict.h"
 #include "cover.h"
+#include "../common/zstd_internal.h" /* includes zstd.h */
+#ifndef ZDICT_STATIC_LINKING_ONLY
+#define ZDICT_STATIC_LINKING_ONLY
+#endif
+#include "zdict.h"
 
 /*-*************************************
 *  Constants

lib/dictBuilder/cover.h

@@ -8,10 +8,6 @@
  * You may select, at your option, one of the above-listed licenses.
  */
 
-#ifndef ZDICT_STATIC_LINKING_ONLY
-#  define ZDICT_STATIC_LINKING_ONLY
-#endif
-
 #include <stdio.h>  /* fprintf */
 #include <stdlib.h> /* malloc, free, qsort */
 #include <string.h> /* memset */
@@ -20,7 +16,10 @@
 #include "../common/pool.h"
 #include "../common/threading.h"
 #include "../common/zstd_internal.h" /* includes zstd.h */
-#include "../zdict.h"
+#ifndef ZDICT_STATIC_LINKING_ONLY
+#define ZDICT_STATIC_LINKING_ONLY
+#endif
+#include "zdict.h"
 
 /**
  * COVER_best_t is used for two purposes:

lib/dictBuilder/fastcover.c

@@ -16,17 +16,16 @@
 #include <string.h> /* memset */
 #include <time.h>   /* clock */
 
-#ifndef ZDICT_STATIC_LINKING_ONLY
-#  define ZDICT_STATIC_LINKING_ONLY
-#endif
-
 #include "../common/mem.h" /* read */
 #include "../common/pool.h"
 #include "../common/threading.h"
+#include "cover.h"
 #include "../common/zstd_internal.h" /* includes zstd.h */
 #include "../compress/zstd_compress_internal.h" /* ZSTD_hash*() */
-#include "../zdict.h"
-#include "cover.h"
+#ifndef ZDICT_STATIC_LINKING_ONLY
+#define ZDICT_STATIC_LINKING_ONLY
+#endif
+#include "zdict.h"
 
 
 /*-*************************************