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Re: PATCH: Add x86 integer intrinsics


int
rol(int x, int y)
{
 return (x << y) | (x >> (32 - y));
 }

Uhm, because it is not a rotate (the >> shift is arithmetic). But this works:

return ((unsigned)x << y) + ((unsigned)x >> (32-y));

and the dumps show that it is done before inlining.

I could not get it to work for rolb/rolw due to int promotion, but I think we should treat this as a tree-level missed optimization.

Paolo

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