Linus Torvalds 66c9c6c0fb block-sha1: improved SHA1 hashing ... I think I have found a way to avoid the gcc crazyness. Lookie here: # TIME[s] SPEED[MB/s] rfc3174 5.094 119.8 rfc3174 5.098 119.7 linus 1.462 417.5 linusas 2.008 304 linusas2 1.878 325 mozilla 5.566 109.6 mozillaas 5.866 104.1 openssl 1.609 379.3 spelvin 1.675 364.5 spelvina 1.601 381.3 nettle 1.591 383.6 notice? I outperform all the hand-tuned asm on 32-bit too. By quite a margin, in fact. Now, I didn't try a P4, and it's possible that it won't do that there, but the 32-bit code generation sure looks impressive on my Nehalem box. The magic? I force the stores to the 512-bit hash bucket to be done in order. That seems to help a lot. The diff is trivial (on top of the "rename registers with cpp" patch), as appended. And it does seem to fix the P4 issues too, although I can obviously (once again) only test Prescott, and only in 64-bit mode: # TIME[s] SPEED[MB/s] rfc3174 1.662 36.73 rfc3174 1.64 37.22 linus 0.2523 241.9 linusas 0.4367 139.8 linusas2 0.4487 136 mozilla 0.9704 62.9 mozillaas 0.9399 64.94 that's some really impressive improvement. All from just saying "do the stores in the order I told you to, dammit!" to the compiler. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>		2009-08-07 22:32:46 -07:00
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sha1.c	block-sha1: improved SHA1 hashing	2009-08-07 22:32:46 -07:00
sha1.h	block-sha1: get rid of redundant 'lenW' context	2009-08-06 13:56:45 -07:00