[llvm] [AMDGPU] Fix `AMDGPUPromoteAlloca` handling certain loads incorrectly (PR #123173)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,16 @@
+; 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
+
+define void @vector_alloca_with_loaded_value_as_index(<2 x i64> %arg) {
+; CHECK-LABEL: define void @vector_alloca_with_loaded_value_as_index(
+; CHECK-SAME: <2 x i64> [[ARG:%.*]]) {
+; CHECK-NEXT:    [[TMP1:%.*]] = extractelement <2 x i64> [[ARG]], i64 0
+; CHECK-NEXT:    [[TMP2:%.*]] = extractelement <2 x i64> [[ARG]], i64 1
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca <2 x i64>, align 16
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arsenm wrote:

This is using the wrong address space 

https://github.com/llvm/llvm-project/pull/123173