[llvm] [AMDGPU][PromoteAlloca] Support memsets to ptr allocas (PR #80678)

[Matt Arsenault via llvm-commits]

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@@ -84,4 +84,16 @@ entry:
   ret void
 }
 
+define amdgpu_kernel void @memset_ptr_alloca(ptr %out) {
+; CHECK-LABEL: @memset_ptr_alloca(
+; CHECK-NEXT:    store i64 0, ptr [[OUT:%.*]], align 8
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca [6 x ptr], align 16, addrspace(5)
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arsenm wrote:

Also test the vector of pointer case 

https://github.com/llvm/llvm-project/pull/80678