Re: [PATCH] add slice by 8 algorithm to crc32.c

From: George Spelvin
Date: Mon Aug 08 2011 - 06:52:08 EST


> I prefer to keep the current code which (at the time) generated good code
> for at least ppc:
> /* Align it */
> if (unlikely((long)buf & 3 && len)) {
> do {
> DO_CRC(*buf++);
> } while ((--len) && ((long)buf)&3);
> }

Ah, I was looking at fzago's initial patch; I hadn't realized you'd
tweaked it. That's pretty much what I was talking about.

Would
if (unlikely((long)buf & 3) && len) {

give the compiler better hints? len != 0 is awfully
likely, actually.
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