IBM Z: Adjust compressBound() for DFLTCC (and several other fixes) by iii-i · Pull Request #1049 · zlib-ng/zlib-ng

iii-i · 2021-10-11T12:50:40Z

Hi,

a bug with compressBound() + DFLTCC was discovered in zlib. While porting the fix to zlib-ng, I also stumbled upon several other problems. This PR fixes them all.

Best regards,
Ilya

Do not use relative includes, since they are valid only within the source directory. Rely on the build system to pass the necessary include flags instead.

This fixes link failures when using CFLAGS=-m31 on IBM Z. All the other tests are already linked this way.

codecov · 2021-10-11T12:53:31Z

Codecov Report

Merging #1049 (75d2140) into develop (b418e9c) will decrease coverage by 0.02%.
The diff coverage is 50.00%.

@@             Coverage Diff             @@
##           develop    #1049      +/-   ##
===========================================
- Coverage    79.48%   79.46%   -0.03%     
===========================================
  Files           85       85              
  Lines         8658     8663       +5     
  Branches      1398     1401       +3     
===========================================
+ Hits          6882     6884       +2     
- Misses        1228     1230       +2     
- Partials       548      549       +1

Flag	Coverage Δ
macos_clang	`69.88% <33.33%> (-0.03%)`	⬇️
macos_gcc	`68.53% <ø> (ø)`
ubuntu_clang	`75.45% <33.33%> (-0.03%)`	⬇️
ubuntu_clang_debug	`75.57% <33.33%> (-0.02%)`	⬇️
ubuntu_clang_inflate_allow_invalid_dist	`75.19% <33.33%> (-0.03%)`	⬇️
ubuntu_clang_inflate_strict	`75.39% <33.33%> (-0.03%)`	⬇️
ubuntu_clang_mmap	`75.42% <33.33%> (-0.03%)`	⬇️
ubuntu_clang_msan	`75.45% <33.33%> (-0.03%)`	⬇️
ubuntu_clang_pigz	`36.16% <0.00%> (-0.02%)`	⬇️
ubuntu_clang_pigz_no_optim	`40.92% <0.00%> (-0.03%)`	⬇️
ubuntu_clang_pigz_no_threads	`35.66% <0.00%> (-0.02%)`	⬇️
ubuntu_clang_reduced_mem	`75.71% <33.33%> (-0.03%)`	⬇️
ubuntu_gcc	`74.88% <100.00%> (ø)`
ubuntu_gcc_aarch64	`76.77% <100.00%> (ø)`
ubuntu_gcc_aarch64_compat_no_opt	`74.55% <ø> (ø)`
ubuntu_gcc_aarch64_no_acle	`76.23% <ø> (ø)`
ubuntu_gcc_aarch64_no_neon	`76.54% <ø> (ø)`
ubuntu_gcc_armhf	`76.77% <100.00%> (ø)`
ubuntu_gcc_armhf_compat_no_opt	`74.52% <ø> (ø)`
ubuntu_gcc_armhf_no_acle	`77.05% <100.00%> (ø)`
ubuntu_gcc_armhf_no_neon	`77.33% <100.00%> (ø)`
ubuntu_gcc_armsf	`76.78% <100.00%> (ø)`
ubuntu_gcc_armsf_compat_no_opt	`74.52% <ø> (ø)`
ubuntu_gcc_compat_no_opt	`75.51% <100.00%> (ø)`
ubuntu_gcc_compat_sprefix	`74.79% <ø> (ø)`
ubuntu_gcc_mingw_i686	`0.00% <ø> (ø)`
ubuntu_gcc_mingw_x86_64	`0.00% <ø> (ø)`
ubuntu_gcc_no_avx2	`76.84% <ø> (ø)`
ubuntu_gcc_no_ctz	`77.74% <ø> (ø)`
ubuntu_gcc_no_ctzll	`77.41% <ø> (ø)`
ubuntu_gcc_no_pclmulqdq	`73.62% <ø> (ø)`
ubuntu_gcc_no_sse2	`76.10% <ø> (ø)`
ubuntu_gcc_no_sse4	`73.97% <ø> (ø)`
ubuntu_gcc_o3	`74.09% <ø> (ø)`
ubuntu_gcc_osb	`76.85% <100.00%> (+<0.01%)`	⬆️
ubuntu_gcc_pigz	`36.47% <ø> (-0.09%)`	⬇️
ubuntu_gcc_pigz_aarch64	`38.57% <ø> (-0.04%)`	⬇️
ubuntu_gcc_ppc	`74.57% <ø> (ø)`
ubuntu_gcc_ppc64	`77.61% <ø> (ø)`
ubuntu_gcc_ppc64le	`76.07% <ø> (ø)`
ubuntu_gcc_ppc_no_power8	`77.37% <ø> (ø)`
ubuntu_gcc_s390x	`75.89% <28.57%> (-0.04%)`	⬇️
ubuntu_gcc_sparc64	`78.65% <ø> (ø)`
ubuntu_gcc_sprefix	`74.57% <ø> (ø)`
win64_gcc	`∅ <ø> (∅)`
win64_gcc_compat_no_opt	`∅ <ø> (∅)`

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
arch/s390/crc32-vx.c	`100.00% <ø> (ø)`
arch/s390/dfltcc_common.c	`89.65% <ø> (ø)`
arch/s390/dfltcc_deflate.c	`13.49% <0.00%> (-0.17%)`	⬇️
arch/s390/dfltcc_inflate.c	`15.87% <ø> (ø)`
arch/s390/s390.c	`100.00% <ø> (ø)`
compress.c	`89.18% <100.00%> (+0.95%)`	⬆️
test/example.c	`81.84% <100.00%> (ø)`
trees.c	`96.17% <0.00%> (-0.28%)`	⬇️

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arch/s390/dfltcc_common.h

compress.c

test/example.c

The zlib manual does not specify a strict contract for inflateGetDictionary(), it merely says that it "Returns the sliding dictionary being maintained by inflate", which is an implementation detail. IBM Z inflate's behavior differs from that of software, and may change in the future to boot.

Intermediate CRC32 value was moved from strm->adler to state->crc_fold.

compress.c

When DFLTCC was introduced, deflateBound() was adjusted, but compressBound() was not, leading to compression failures when using compressBound() + compress() with poorly compressible data.

- Fix hangs on macOS #1031 - Fix minideflate write buffers being overwritten #1060 - Fix build problems when building outside of source dir #1049 - Fix build problems on arm2-7 #1030 - Fixed some compile warnings #1020 #1036 #1037 #1048 - Improved posix memalign support #888 - Improvements to testing #637 #1026 #1035 #1051 #1056 #1063 #1067 - Improvements for integration into other projects #1022 #1042 - Code style fixes #637 #1040 #1050

- Fix hangs on macOS #1031 - Fix minideflate write buffers being overwritten #1060 - Fix deflateBound and compressBound returning too small size estimates #1071 - Fix build problems when building outside of source dir #1049 - Fix build problems on arm2-7 #1030 - Fixed some compile warnings #1020 #1036 #1037 #1048 - Improved posix memalign support #888 - Improvements to testing #637 #1026 #1032 #1035 #1051 #1056 #1063 #1067 - Improvements for integration into other projects #1022 #1042 - Code style fixes #637 #1040 #1050 #1075

- Fix hangs on macOS #1031 - Fix minideflate write buffers being overwritten #1060 - Fix deflateBound and compressBound returning too small size estimates #1049 #1071 - Fix incorrect function declaration warning #1080 - Fix build problems when building outside of source dir #1049 - Fix build problems on arm2-7 #1030 - Fixed some compile warnings #1020 #1036 #1037 #1048 - Improved posix memalign support #888 - Improvements to testing #637 #1026 #1032 #1035 #1049 #1051 #1056 #1063 #1067 - Improvements for integration into other projects #1022 #1042 - Code style fixes #637 #1040 #1050 #1075

- Fix hangs on macOS #1031 - Fix minideflate write buffers being overwritten #1060 - Fix deflateBound and compressBound returning too small size estimates #1049 #1071 - Fix incorrect function declaration warning #1080 - Fix build problems when building outside of source dir #1049 - Fix build problems on arm2-7 #1030 - Fixed some compile warnings #1020 #1036 #1037 #1048 - Improved posix memalign support #888 - Improvements to testing #637 #1026 #1032 #1035 #1049 #1051 #1056 #1063 #1067 #1079 - Improvements for integration into other projects #1022 #1042 - Code style fixes #637 #1040 #1050 #1075

iii-i added 2 commits October 11, 2021 13:15

IBM Z: Fix building outside of a source directory

b5720f1

Do not use relative includes, since they are valid only within the source directory. Rely on the build system to pass the necessary include flags instead.

Link crc32_test and infcover with $(CFLAGS)

97602c3

This fixes link failures when using CFLAGS=-m31 on IBM Z. All the other tests are already linked this way.