[llvm] InstCombine: Process addrspacecast uses in PointerReplacer (PR #91953)

[Yaxun Liu via llvm-commits]

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@@ -0,0 +1,81 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -mtriple=amdgcn-amd-amdhsa -passes=instcombine %s | FileCheck %s
+
+; It is illegal to pass ptr addrspace(4) in %arg by addrspacecasting
+; to ptr addrspace(5) to pass off to the stack argument. A temporary
+; alloca and memcpy is necessary.
+define void @issue68120_invalid_addrspacecast_introduced_0(ptr addrspace(4) byref([56 x i8]) %arg) {
+; CHECK-LABEL: define void @issue68120_invalid_addrspacecast_introduced_0(
+; CHECK-SAME: ptr addrspace(4) byref([56 x i8]) [[ARG:%.*]]) {
+; CHECK-NEXT:    [[ADDRSPACECAST_0_TO_5:%.*]] = alloca [56 x i8], align 1, addrspace(5)
+; CHECK-NEXT:    call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) noundef align 1 dereferenceable(56) [[ADDRSPACECAST_0_TO_5]], ptr addrspace(4) noundef align 1 dereferenceable(56) [[ARG]], i64 56, i1 false)
+; CHECK-NEXT:    call void @byval_func(ptr addrspace(5) [[ADDRSPACECAST_0_TO_5]])
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca [56 x i8], addrspace(5)
+  %alloca1 = alloca [56 x i8], addrspace(5)
+  call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) %alloca, ptr addrspace(4) %arg, i64 56, i1 false)
+  call void @llvm.memcpy.p5.p5.i64(ptr addrspace(5) %alloca1, ptr addrspace(5) %alloca, i64 56, i1 false)
+  %addrspacecast.alloca1 = addrspacecast ptr addrspace(5) %alloca1 to ptr
+  %addrspacecast.0.to.5 = addrspacecast ptr %addrspacecast.alloca1 to ptr addrspace(5)
+  call void @byval_func(ptr addrspace(5) %addrspacecast.0.to.5)
+  ret void
+}
+
+; Further reduced variant that already eliminated one of the copies
+define void @issue68120_invalid_addrspacecast_introduced_1(ptr addrspace(4) byref([56 x i8]) %arg) {
+; CHECK-LABEL: define void @issue68120_invalid_addrspacecast_introduced_1(
+; CHECK-SAME: ptr addrspace(4) byref([56 x i8]) [[ARG:%.*]]) {
+; CHECK-NEXT:    [[ADDRSPACECAST_0_TO_5:%.*]] = alloca [56 x i8], align 1, addrspace(5)
+; CHECK-NEXT:    call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) noundef align 1 dereferenceable(56) [[ADDRSPACECAST_0_TO_5]], ptr addrspace(4) noundef align 1 dereferenceable(56) [[ARG]], i64 56, i1 false)
+; CHECK-NEXT:    call void @byval_func(ptr addrspace(5) [[ADDRSPACECAST_0_TO_5]])
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca [56 x i8], addrspace(5)
+  call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) %alloca, ptr addrspace(4) %arg, i64 56, i1 false)
+  %addrspacecast.alloca = addrspacecast ptr addrspace(5) %alloca to ptr
+  %addrspacecast.0.to.5 = addrspacecast ptr %addrspacecast.alloca to ptr addrspace(5)
+  call void @byval_func(ptr addrspace(5) %addrspacecast.0.to.5)
+  ret void
+}
+
+define void @issue68120_use_cast_to_as0(ptr addrspace(4) byref([56 x i8]) %arg) {
+; CHECK-LABEL: define void @issue68120_use_cast_to_as0(
+; CHECK-SAME: ptr addrspace(4) byref([56 x i8]) [[ARG:%.*]]) {
+; CHECK-NEXT:    [[ALLOCA:%.*]] = alloca [56 x i8], align 1, addrspace(5)
+; CHECK-NEXT:    call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) noundef align 1 dereferenceable(56) [[ALLOCA]], ptr addrspace(4) noundef align 1 dereferenceable(56) [[ARG]], i64 56, i1 false)
+; CHECK-NEXT:    [[ADDRSPACECAST_ALLOCA:%.*]] = addrspacecast ptr addrspace(5) [[ALLOCA]] to ptr
+; CHECK-NEXT:    call void @other_func(ptr [[ADDRSPACECAST_ALLOCA]])
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca [56 x i8], addrspace(5)
+  call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) %alloca, ptr addrspace(4) %arg, i64 56, i1 false)
+  %addrspacecast.alloca = addrspacecast ptr addrspace(5) %alloca to ptr
+  %addrspacecast.0.to.5 = addrspacecast ptr %addrspacecast.alloca to ptr addrspace(5)
+  call void @other_func(ptr %addrspacecast.alloca)
+  ret void
+}
+
+define void @issue68120_uses_invalid_addrspacecast(ptr addrspace(4) byref([56 x i8]) %arg) {
+; CHECK-LABEL: define void @issue68120_uses_invalid_addrspacecast(
+; CHECK-SAME: ptr addrspace(4) byref([56 x i8]) [[ARG:%.*]]) {
+; CHECK-NEXT:    [[ADDRSPACECAST_0_TO_5:%.*]] = alloca [56 x i8], align 1, addrspace(5)
+; CHECK-NEXT:    call void @llvm.memcpy.p5.p4.i64(ptr addrspace(5) noundef align 1 dereferenceable(56) [[ADDRSPACECAST_0_TO_5]], ptr addrspace(4) noundef align 1 dereferenceable(56) [[ARG]], i64 56, i1 false)
+; CHECK-NEXT:    call void @byval_func(ptr addrspace(5) [[ADDRSPACECAST_0_TO_5]])
+; CHECK-NEXT:    ret void
+;
+  %alloca = alloca [56 x i8], addrspace(5)
+  %alloca1 = alloca [56 x i8], addrspace(5)
+  %illegal.cast = addrspacecast ptr addrspace(4) %arg to ptr addrspace(5)
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yxsamliu wrote:

Do we know what generates this invalid IR? Should it be fixed?

In general, should we check invalid addr space cast and emit error, to prevent similar issues in future?

https://github.com/llvm/llvm-project/pull/91953