[llvm] [AMDGPU] Handle lowering addrspace casts from LDS to FLAT address in amdgpu-sw-lower-lds. (PR #121214)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,76 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals all --version 5
+; RUN: opt < %s -passes=amdgpu-sw-lower-lds -S  -mtriple=amdgcn-amd-amdhsa | FileCheck %s
+ at lds = internal addrspace(3) global [5 x i32] poison, align 16
+
+;.
+; CHECK: @llvm.amdgcn.sw.lds.k0 = internal addrspace(3) global ptr poison, no_sanitize_address, align 16, !absolute_symbol [[META0:![0-9]+]]
+; CHECK: @llvm.amdgcn.sw.lds.k0.md = internal addrspace(1) global %llvm.amdgcn.sw.lds.k0.md.type { %llvm.amdgcn.sw.lds.k0.md.item { i32 0, i32 8, i32 32 }, %llvm.amdgcn.sw.lds.k0.md.item { i32 32, i32 20, i32 64 } }, no_sanitize_address
+;.
+define amdgpu_kernel void @k0() sanitize_address {
+; CHECK-LABEL: define amdgpu_kernel void @k0(
+; CHECK-SAME: ) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:  [[WID:.*]]:
+; CHECK-NEXT:    [[TMP0:%.*]] = call i32 @llvm.amdgcn.workitem.id.x()
+; CHECK-NEXT:    [[TMP1:%.*]] = call i32 @llvm.amdgcn.workitem.id.y()
+; CHECK-NEXT:    [[TMP2:%.*]] = call i32 @llvm.amdgcn.workitem.id.z()
+; CHECK-NEXT:    [[TMP3:%.*]] = or i32 [[TMP0]], [[TMP1]]
+; CHECK-NEXT:    [[TMP4:%.*]] = or i32 [[TMP3]], [[TMP2]]
+; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq i32 [[TMP4]], 0
+; CHECK-NEXT:    br i1 [[TMP5]], label %[[MALLOC:.*]], label %[[BB18:.*]]
+; CHECK:       [[MALLOC]]:
+; CHECK-NEXT:    [[TMP6:%.*]] = load i32, ptr addrspace(1) getelementptr inbounds ([[LLVM_AMDGCN_SW_LDS_K0_MD_TYPE:%.*]], ptr addrspace(1) @llvm.amdgcn.sw.lds.k0.md, i32 0, i32 1, i32 0), align 4
+; CHECK-NEXT:    [[TMP7:%.*]] = load i32, ptr addrspace(1) getelementptr inbounds ([[LLVM_AMDGCN_SW_LDS_K0_MD_TYPE]], ptr addrspace(1) @llvm.amdgcn.sw.lds.k0.md, i32 0, i32 1, i32 2), align 4
+; CHECK-NEXT:    [[TMP8:%.*]] = add i32 [[TMP6]], [[TMP7]]
+; CHECK-NEXT:    [[TMP9:%.*]] = zext i32 [[TMP8]] to i64
+; CHECK-NEXT:    [[TMP10:%.*]] = call ptr @llvm.returnaddress(i32 0)
+; CHECK-NEXT:    [[TMP11:%.*]] = ptrtoint ptr [[TMP10]] to i64
+; CHECK-NEXT:    [[TMP12:%.*]] = call i64 @__asan_malloc_impl(i64 [[TMP9]], i64 [[TMP11]])
+; CHECK-NEXT:    [[TMP13:%.*]] = inttoptr i64 [[TMP12]] to ptr addrspace(1)
+; CHECK-NEXT:    store ptr addrspace(1) [[TMP13]], ptr addrspace(3) @llvm.amdgcn.sw.lds.k0, align 8
+; CHECK-NEXT:    [[TMP14:%.*]] = getelementptr inbounds i8, ptr addrspace(1) [[TMP13]], i64 8
+; CHECK-NEXT:    [[TMP15:%.*]] = ptrtoint ptr addrspace(1) [[TMP14]] to i64
+; CHECK-NEXT:    call void @__asan_poison_region(i64 [[TMP15]], i64 24)
+; CHECK-NEXT:    [[TMP16:%.*]] = getelementptr inbounds i8, ptr addrspace(1) [[TMP13]], i64 52
+; CHECK-NEXT:    [[TMP17:%.*]] = ptrtoint ptr addrspace(1) [[TMP16]] to i64
+; CHECK-NEXT:    call void @__asan_poison_region(i64 [[TMP17]], i64 44)
+; CHECK-NEXT:    br label %[[BB18]]
+; CHECK:       [[BB18]]:
+; CHECK-NEXT:    [[XYZCOND:%.*]] = phi i1 [ false, %[[WID]] ], [ true, %[[MALLOC]] ]
+; CHECK-NEXT:    call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    [[TMP19:%.*]] = load ptr addrspace(1), ptr addrspace(3) @llvm.amdgcn.sw.lds.k0, align 8
+; CHECK-NEXT:    [[TMP20:%.*]] = load i32, ptr addrspace(1) getelementptr inbounds ([[LLVM_AMDGCN_SW_LDS_K0_MD_TYPE]], ptr addrspace(1) @llvm.amdgcn.sw.lds.k0.md, i32 0, i32 1, i32 0), align 4
+; CHECK-NEXT:    [[TMP21:%.*]] = getelementptr inbounds i8, ptr addrspace(3) @llvm.amdgcn.sw.lds.k0, i32 [[TMP20]]
+; CHECK-NEXT:    [[TMP22:%.*]] = ptrtoint ptr addrspace(3) [[TMP21]] to i32
+; CHECK-NEXT:    [[TMP23:%.*]] = getelementptr inbounds i8, ptr addrspace(1) [[TMP19]], i32 [[TMP22]]
+; CHECK-NEXT:    [[TMP24:%.*]] = addrspacecast ptr addrspace(1) [[TMP23]] to ptr
+; CHECK-NEXT:    [[GEP:%.*]] = getelementptr inbounds [5 x i32], ptr [[TMP24]], i64 0, i64 0
+; CHECK-NEXT:    store i32 1, ptr [[GEP]], align 4
+; CHECK-NEXT:    br label %[[CONDFREE:.*]]
+; CHECK:       [[CONDFREE]]:
+; CHECK-NEXT:    call void @llvm.amdgcn.s.barrier()
+; CHECK-NEXT:    br i1 [[XYZCOND]], label %[[FREE:.*]], label %[[END:.*]]
+; CHECK:       [[FREE]]:
+; CHECK-NEXT:    [[TMP25:%.*]] = call ptr @llvm.returnaddress(i32 0)
+; CHECK-NEXT:    [[TMP26:%.*]] = ptrtoint ptr [[TMP25]] to i64
+; CHECK-NEXT:    [[TMP27:%.*]] = ptrtoint ptr addrspace(1) [[TMP19]] to i64
+; CHECK-NEXT:    call void @__asan_free_impl(i64 [[TMP27]], i64 [[TMP26]])
+; CHECK-NEXT:    br label %[[END]]
+; CHECK:       [[END]]:
+; CHECK-NEXT:    ret void
+;
+  %gep = getelementptr inbounds [5 x i32], ptr addrspacecast (ptr addrspace(3) @lds to ptr), i64 0, i64 0
+  store i32 1, ptr %gep, align 4
+  ret void
+}
+
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arsenm wrote:

What happens if you have a generic pointer downcast to a local pointer? What happens with vectors of pointers? 

https://github.com/llvm/llvm-project/pull/121214