[AMDGPU] Promote uniform i16 ops to i32 ops for targets that have 16 bit instructions

Differential Revision: https://reviews.llvm.org/D24125



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282624 91177308-0d34-0410-b5e6-96231b3b80d8
8 files changed