[PATCH][X86] Fix assertion failure caused by a wrong folding of vector shifts by immediate count (regression introduced by my r198113).

[Nadav Rotem]

LGTM. 

On Jan 13, 2014, at 8:24 AM, Andrea Di Biagio <andrea.dibiagio at gmail.com> wrote:

> Hi,
> 
> This patch fixes an assertion failure caused by the algorithm
> introduced by my r198113. Revision 198113 introduced an algorithm that
> tries to fold a vector shift by immediate count into a build_vector if
> the input vector to the shift is a known vector of constants.
> 
> However, the algorithm only works under the assumption that the input
> vector type and the shift type are exactly the same.
> This patch conservatively disables the folding of the vector shift by
> immediate count if the input vector type and the shift valuetype are
> not the same.
> 
> Thanks to Patrik Hägglund H for providing the test case.
> 
> Please let me know if ok to submit.
> 
> Thanks,
> Andrea Di Biagio
> SN Systems - Sony Computer Entertainment Group
> <patch.diff>