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| author | Lasse Collin <lasse.collin@tukaani.org> | 2014-08-03 21:08:12 +0300 |
|---|---|---|
| committer | Lasse Collin <lasse.collin@tukaani.org> | 2014-08-03 21:08:12 +0300 |
| commit | a9477d1e0c6fd0e47e637d051e7b9e2a5d9af517 (patch) | |
| tree | 2775facf874762fff0d2f2fafacbbe2b70f07327 /src/liblzma/check/crc32_tablegen.c | |
| parent | liblzma: SHA-256: Remove the GCC #pragma that became unneeded. (diff) | |
| download | xz-a9477d1e0c6fd0e47e637d051e7b9e2a5d9af517.tar.xz | |
liblzma: SHA-256: Optimize the way rotations are done.
This looks weird because the rotations become sequential,
but it helps quite a bit on both 32-bit and 64-bit x86:
- It requires fewer instructions on two-operand
instruction sets like x86.
- It requires one register less which matters especially
on 32-bit x86.
I hope this doesn't hurt other archs.
I didn't invent this idea myself, but I don't remember where
I saw it first.
Diffstat (limited to 'src/liblzma/check/crc32_tablegen.c')
0 files changed, 0 insertions, 0 deletions