[PATCH] X86: fold SSE2/AVX2 logical shift by immediate amout into zero vector when possible

[Andrea_DiBiagio at sn.scee.net]

> From: Nadav Rotem <nrotem at apple.com>
> These vectors with these constants can be generated during 
> legalization.  But it’s not a big deal and we can do without it. 
> 

True..
 
> The behavior of shifts by amount larger than the element size is defined 

> for x86 SSE2/AVX2.
> 
> Yes, but we are looking at the semantics of the llvm SelectionDAG, 
> and we want to lower it to x86.  :)
> 
> In any case, this is correct and I don’t see any reason not to 
> commit the patch as is. 

Thanks.
Btw. I have no commit access to the repository.
Could (any of) you please commit this change for me? :-)

Andrea Di Biagio
SN Systems - Sony Computer Entertainment Group

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