AMDGPU: mark llvm.amdgcn.image.atomic.* as a source of divergence

Summary:
When multiple threads perform an atomic op with the same arguments, they
will usually see different return values.

Reviewers: arsenm, tstellarAMD

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D18101

llvm-svn: 263440

1 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
index d1bb40aff9d..540ca5f399f 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp
@@ -126,6 +126,19 @@ static bool isIntrinsicSourceOfDivergence(const TargetIntrinsicInfo *TII,
   case Intrinsic::r600_read_tidig_x:
   case Intrinsic::r600_read_tidig_y:
   case Intrinsic::r600_read_tidig_z:
+  case Intrinsic::amdgcn_image_atomic_swap:
+  case Intrinsic::amdgcn_image_atomic_add:
+  case Intrinsic::amdgcn_image_atomic_sub:
+  case Intrinsic::amdgcn_image_atomic_smin:
+  case Intrinsic::amdgcn_image_atomic_umin:
+  case Intrinsic::amdgcn_image_atomic_smax:
+  case Intrinsic::amdgcn_image_atomic_umax:
+  case Intrinsic::amdgcn_image_atomic_and:
+  case Intrinsic::amdgcn_image_atomic_or:
+  case Intrinsic::amdgcn_image_atomic_xor:
+  case Intrinsic::amdgcn_image_atomic_inc:
+  case Intrinsic::amdgcn_image_atomic_dec:
+  case Intrinsic::amdgcn_image_atomic_cmpswap:
     return true;
   }