[llvm] [AMDGPU] Promote nestedGEP allocas to vectors (PR #141199)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,55 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -mtriple=amdgcn-amd-amdhsa -passes=amdgpu-promote-alloca < %s | FileCheck %s
+target triple = "amdgcn-amd-amdhsa"
+define amdgpu_ps void @scalar_alloca_ptr_with_vector_gep_of_gep(i32 %j) #0 {
+; CHECK-LABEL: define amdgpu_ps void @scalar_alloca_ptr_with_vector_gep_of_gep(
+; CHECK-SAME: i32 [[J:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[SORTEDFRAGMENTS:%.*]] = freeze <20 x i32> poison
+; CHECK-NEXT:    [[TMP0:%.*]] = mul i32 [[J]], 2
+; CHECK-NEXT:    [[TMP1:%.*]] = mul i32 [[J]], 2
+; CHECK-NEXT:    [[TMP2:%.*]] = add i32 1, [[TMP1]]
+; CHECK-NEXT:    [[TMP3:%.*]] = extractelement <20 x i32> [[SORTEDFRAGMENTS]], i32 [[TMP2]]
+; CHECK-NEXT:    ret void
+;
+entry:
+  %SortedFragments = alloca [10 x <2 x i32>], align 8, addrspace(5)
+  %0 = getelementptr [10 x <2 x i32>], ptr addrspace(5) %SortedFragments, i32 0, i32 %j
+  %1 = getelementptr i8, ptr addrspace(5) %0, i32 4
+  %2 = load i32, ptr addrspace(5) %1, align 4
+  ret void
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arsenm wrote:

Better to make this not dead code. Also use named values in tests 

https://github.com/llvm/llvm-project/pull/141199