On the x86_64, does one have to zero a vector register before filling it completely ?

[Toon Moene]

Tim Prince wrote:

 > If you want those, you must request them with -mtune=barcelona.

OK, so it is an alignment issue (with -mtune=barcelona):

.L6:
         movups  0(%rbp,%rax), %xmm0
         movups  (%rbx,%rax), %xmm1
         incl    %ecx
         addps   %xmm1, %xmm0
         movaps  %xmm0, (%r8,%rax)
         addq    $16, %rax
         cmpl    %r10d, %ecx
         jb      .L6

Thanks,

-- 
Toon Moene - e-mail: toon@moene.org - phone: +31 346 214290
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