[llvm] [AMDGPU] Fix S_ADD_I32 frame index folding emitting COPY with immediate (PR #212440)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,61 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a -O3 < %s | FileCheck %s
+;
+; eliminateFrameIndex must emit s_mov_b32 for S_ADD_I32 %fi, imm.
+
+define amdgpu_kernel void @kernel() {
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arsenm wrote:

I'd rather have both 

https://github.com/llvm/llvm-project/pull/212440