Nicolai Haehnle c3187b408e AMDGPU: Move v_readlane lane select from VGPR to SGPR
Summary:
Fix a compiler bug when the lane select happens to end up in a VGPR.

Clarify the semantic of the corresponding intrinsic to be that of
the corresponding GLSL: the lane select must be uniform across a
wave front, otherwise results are undefined.

Reviewers: arsenm

Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, t-tye, llvm-commits

Differential Revision: https://reviews.llvm.org/D32343

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301197 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-24 17:17:36 +00:00
..
2017-04-21 06:14:38 +00:00