[cfe-dev] Inefficient code generation for _mm_test{z, c, nzc} (SSE4.1)

Craig Topper craig.topper at gmail.com
Thu Apr 12 20:15:50 PDT 2012


I intend to look into fixing that. There's likely something missing during
DAG combine that should be able to fix this up.

On Thu, Apr 12, 2012 at 3:23 AM, Florian Pflug <fgp at phlo.org> wrote:

> On Apr12, 2012, at 08:38 , Craig Topper wrote:
> > Interestingly, the AVX ptest intrinsics are correctly taking 4 x i64
> arguments. I'll fix the 128-bit versions to take 2 x i64.
>
> Wouldn't it also make more sense for the PTEST intrinsics to return an i1,
> not an i32? One could then use the results of
> llvm.x86.sse41.ptest{z,c,nc} directly as a condition for br, without the
> intermediate icmp step. Or so I imagine, at least.
>
> best regards,
> Florian Pflug
>
>


-- 
~Craig
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