crypto: twofish-avx - tune assembler code for more performance
Patch replaces 'movb' instructions with 'movzbl' to break false register dependencies and interleaves instructions better for out-of-order scheduling. Tested on Intel Core i5-2450M and AMD FX-8100. tcrypt ECB results: Intel Core i5-2450M: size old-vs-new new-vs-3way old-vs-3way enc dec enc dec enc dec 256 1.12x 1.13x 1.36x 1.37x 1.21x 1.22x 1k 1.14x 1.14x 1.48x 1.49x 1.29x 1.31x 8k 1.14x 1.14x 1.50x 1.52x 1.32x 1.33x AMD FX-8100: size old-vs-new new-vs-3way old-vs-3way enc dec enc dec enc dec 256 1.10x 1.11x 1.01x 1.01x 0.92x 0.91x 1k 1.11x 1.12x 1.08x 1.07x 0.97x 0.96x 8k 1.11x 1.13x 1.10x 1.08x 0.99x 0.97x [v2] - Do instruction interleaving another way to avoid adding new FPU<=>CPU register moves as these cause performance drop on Bulldozer. - Further interleaving improvements for better out-of-order scheduling. Tested-by: Borislav Petkov <bp@alien8.de> Cc: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de> Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Showing
Please register or sign in to comment