[PATCH v2] Try and get overlapping cases fixed.
ajax at redhat.com
Mon May 16 10:01:44 PDT 2011
On 5/16/11 12:26 PM, Jeremy Huddleston wrote:
> Is the one div needed for:
> bpp / 8
> bpp % 8
> really universally faster than the two bitwise ops needed for
> bpp >> 3
> bpp & 0x7
> ? I'm sure most modern compilers will know how to optimize that
> based on the target CPU, but I've always tried to avoid doing mults
> and divs in fast paths where possible.
Even if it's ten cycles slower, I'm going to wager it pales next to the
hundreds-to-millions of cycles of memcpy.
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