Johnothan King 4032050249 Port cksum builtin performance improvements from illumos (#391) ... This commit ports performance optimizations from illumos for the libsum code (used by the cksum and sum builtins): 98bea71f0d The new codepath in libsum uses prefetching and loop unrolling to improve performance (prefetching is done with __builtin_prefetch() or sun_prefetch_read_many() if either is available). Script for testing (note that cksum must be enabled in src/cmd/ksh93/data/builtins.c): #!/bin/ksh builtin cksum || exit 1 for ((i=0; i!=50000; i++)) do cksum -x att /etc/hosts done >/dev/null Results on Linux x86_64 (using CCFLAGS=-O2): $ echo 'UNPATCHED:'; time arch/linux.i386-64/bin/ksh /tmp/foo; echo 'PATCHED'; time /tmp/ksh /tmp/foo UNPATCHED: real 0m09.989s user 0m07.582s sys 0m02.406s PATCHED: real 0m06.536s user 0m04.331s sys 0m02.204s src/lib/libsum/{sum-att.c,sum-crc.c,Mamfile}: - Port the performance optimizations from illumos to 93u+m libsum. To prevent problems with older versions of GCC, avoid the new codepath if GCC is older than the 3.1 release series. Additionally, the ast.h header must be included to handle tcc defining __GNUC__ on FreeBSD. - Apply some build fixes to allow the new codepath to build with Clang 3.6 and newer (my own testing indicates an even better performance improvement with Clang than with GCC).		2021-12-28 22:22:52 +00:00
..
cmd	Add three options to 'ulimit' (#406)	2021-12-28 22:02:20 +00:00
lib	Port cksum builtin performance improvements from illumos (#391)	2021-12-28 22:22:52 +00:00
Mamfile	**/Mamfile: add header comment pointing to MAM docs (re: 6cc2f6a0)	2021-01-25 14:38:58 +00:00