Summary: Although the feature was introduced only in OpenCL C v2.0 spec., it's useful for OpenCL 1.x too and doesn't require HW support.
Reviewers: Anastasia
Subscribers: yaxunl, cfe-commits, bader
Differential Revision: https://reviews.llvm.org/D27453
llvm-svn: 289535
Add support for opencl_unroll_hint attribute from OpenCL v2.0 s6.11.5.
Reusing most of metadata generation from CGLoopInfo helper class.
The code is based on Khronos OpenCL compiler:
https://github.com/KhronosGroup/SPIR/tree/spirv-1.0
Patch by Liu Yaxun (Sam)!
Differential Revision: http://reviews.llvm.org/D16686
llvm-svn: 261350