[llvm] [WIP][AMDGPU] combine uniform AMDGPU lane Intrinsics (PR #116953)

[Pankaj Dwivedi via llvm-commits]

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@@ -0,0 +1,221 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1010 -passes="instcombine,amdgpu-uniform-intrinsic-combine" -S < %s | FileCheck %s --check-prefixes=GFX,GFX10
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1100 -passes="instcombine,amdgpu-uniform-intrinsic-combine" -S < %s | FileCheck %s --check-prefixes=GFX,GFX11
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1200 -passes="instcombine,amdgpu-uniform-intrinsic-combine" -S < %s | FileCheck %s --check-prefixes=GFX,GFX12
+
+define amdgpu_kernel void @permlane64_constant(ptr addrspace(1) %out) {
+; GFX-LABEL: define amdgpu_kernel void @permlane64_constant(
+; GFX-SAME: ptr addrspace(1) [[OUT:%.*]]) #[[ATTR0:[0-9]+]] {
+; GFX-NEXT:    store i32 77, ptr addrspace(1) [[OUT]], align 4
+; GFX-NEXT:    ret void
+;
+  %v = call i32 @llvm.amdgcn.permlane64(i32 77)
+  store i32 %v, ptr addrspace(1) %out
+  ret void
+}
+
+define amdgpu_kernel void @permlane64_undef(ptr addrspace(1) %out) {
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PankajDwivedi-25 wrote:

yeah, true, undef value is uniform anyway. can we keep it as an edge case test?

https://github.com/llvm/llvm-project/pull/116953