AMDGPU: Fix mishandling array allocations when promoting alloca

The canonical form for allocas is a single allocation of the array type.
In case we see a non-canonical array alloca, make sure we aren't
replacing this with an array N times smaller.

llvm-svn: 267916

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp b/llvm/lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
index b7d30d235a0..396f01e441e 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
@@ -483,7 +483,9 @@ static bool collectUsesWithPtrTypes(Value *Val, std::vector<Value*> &WorkList) {
 }
 
 void AMDGPUPromoteAlloca::handleAlloca(AllocaInst &I) {
-  if (!I.isStaticAlloca())
+  // Array allocations are probably not worth handling, since an allocation of
+  // the array type is the canonical form.
+  if (!I.isStaticAlloca() || I.isArrayAllocation())
     return;
 
   IRBuilder<> Builder(&I);