[Bug middle-end/29256] [4.2 regression] loop unrolling performance regression
pinskia at gcc dot gnu dot org
Thu Sep 28 13:47:00 GMT 2006
------- Comment #6 from pinskia at gcc dot gnu dot org 2006-09-28 13:47 -------
(In reply to comment #4)
> On x86_64 4.2 decides to unroll 9 times while on 4.1 it unrolls 8 times. This
> a code-size regression, but other than that? The 4.2 version runs slightly
> faster than the 4.1 version, though the difference may be in the noise.
No, no, no, I and Edmar are not complaining about how many times it unrolled
but the use of index addressing mode instead of offset addressing mode for the
stores and the extra adds.
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