[llvm] [AMDGPU] Handle invariant marks in `AMDGPUPromoteAllocaPass` (PR #124607)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,75 @@
+; 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 -o - | FileCheck %s
+
+declare ptr @llvm.invariant.start.p5(i64, ptr addrspace(5) nocapture)
+declare void @llvm.invariant.end.p5(ptr, i64, ptr addrspace(5) nocapture)
+declare ptr addrspace(5) @llvm.launder.invariant.group.p5(ptr addrspace(5))
+declare ptr addrspace(5) @llvm.strip.invariant.group.p5(ptr addrspace(5))
+
+define amdgpu_kernel void @use_invariant_start_and_end() {
+; CHECK-LABEL: define amdgpu_kernel void @use_invariant_start_and_end() {
+; CHECK-NEXT:  [[BB:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = call noalias nonnull dereferenceable(64) ptr addrspace(4) @llvm.amdgcn.dispatch.ptr()
+; CHECK-NEXT:    [[TMP1:%.*]] = getelementptr inbounds i32, ptr addrspace(4) [[TMP0]], i64 1
+; CHECK-NEXT:    [[TMP2:%.*]] = load i32, ptr addrspace(4) [[TMP1]], align 4, !invariant.load [[META0:![0-9]+]]
+; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr inbounds i32, ptr addrspace(4) [[TMP0]], i64 2
+; CHECK-NEXT:    [[TMP4:%.*]] = load i32, ptr addrspace(4) [[TMP3]], align 4, !range [[RNG1:![0-9]+]], !invariant.load [[META0]]
+; CHECK-NEXT:    [[TMP5:%.*]] = lshr i32 [[TMP2]], 16
+; CHECK-NEXT:    [[TMP6:%.*]] = call range(i32 0, 1024) i32 @llvm.amdgcn.workitem.id.x()
+; CHECK-NEXT:    [[TMP7:%.*]] = call range(i32 0, 1024) i32 @llvm.amdgcn.workitem.id.y()
+; CHECK-NEXT:    [[TMP8:%.*]] = call range(i32 0, 1024) i32 @llvm.amdgcn.workitem.id.z()
+; CHECK-NEXT:    [[TMP9:%.*]] = mul nuw nsw i32 [[TMP5]], [[TMP4]]
+; CHECK-NEXT:    [[TMP10:%.*]] = mul i32 [[TMP9]], [[TMP6]]
+; CHECK-NEXT:    [[TMP11:%.*]] = mul nuw nsw i32 [[TMP7]], [[TMP4]]
+; CHECK-NEXT:    [[TMP12:%.*]] = add i32 [[TMP10]], [[TMP11]]
+; CHECK-NEXT:    [[TMP13:%.*]] = add i32 [[TMP12]], [[TMP8]]
+; CHECK-NEXT:    [[TMP14:%.*]] = getelementptr inbounds [1024 x i32], ptr addrspace(3) @use_invariant_start_and_end.alloca, i32 0, i32 [[TMP13]]
+; CHECK-NEXT:    [[INVARIENT1:%.*]] = call ptr @llvm.invariant.start.p3(i64 0, ptr addrspace(3) [[TMP14]])
+; CHECK-NEXT:    store <2 x i1> zeroinitializer, ptr [[INVARIENT1]], align 1
+; CHECK-NEXT:    call void @llvm.invariant.end.p3(ptr [[INVARIENT1]], i64 0, ptr addrspace(3) [[TMP14]])
+; CHECK-NEXT:    ret void
+;
+bb:
+  %alloca = alloca i32, align 4, addrspace(5)
+  %invarient = call ptr @llvm.invariant.start.p5(i64 0, ptr addrspace(5) %alloca)
+  store <2 x i1> zeroinitializer, ptr %invarient, align 1
+  call void @llvm.invariant.end.p5(ptr %invarient, i64 0, ptr addrspace(5) %alloca)
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arsenm wrote:

I mean the token IR type. What is this pointer value used for 

https://github.com/llvm/llvm-project/pull/124607