Index: llvm/lib/Target/AMDGPU/AMDGPUAliasAnalysis.cpp
===================================================================
--- llvm/lib/Target/AMDGPU/AMDGPUAliasAnalysis.cpp
+++ llvm/lib/Target/AMDGPU/AMDGPUAliasAnalysis.cpp
@@ -91,12 +91,16 @@
 
 bool AMDGPUAAResult::pointsToConstantMemory(const MemoryLocation &Loc,
                                             AAQueryInfo &AAQI, bool OrLocal) {
+  unsigned AS = Loc.Ptr->getType()->getPointerAddressSpace();
+  if (AS == AMDGPUAS::CONSTANT_ADDRESS ||
+      AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
+    return true;
+
   const Value *Base = GetUnderlyingObject(Loc.Ptr, DL);
-  unsigned AS = Base->getType()->getPointerAddressSpace();
+  AS = Base->getType()->getPointerAddressSpace();
   if (AS == AMDGPUAS::CONSTANT_ADDRESS ||
-      AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT) {
+      AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
     return true;
-  }
 
   if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(Base)) {
     if (GV->isConstant())
Index: llvm/test/CodeGen/AMDGPU/aa-points-to-constant-memory.ll
===================================================================
--- /dev/null
+++ llvm/test/CodeGen/AMDGPU/aa-points-to-constant-memory.ll
@@ -0,0 +1,112 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -S -amdgpu-aa-wrapper -amdgpu-aa -instcombine -o - %s | FileCheck %s
+;
+; Test AA::pointsToConstantMemory implementation. These should mostly
+; turn out to be stores to constant memory, and will therefore be
+; deleted as UB.
+
+define void @test_constant_addrspace(i8 addrspace(4)* %p) {
+; CHECK-LABEL: @test_constant_addrspace(
+; CHECK-NEXT:    ret void
+;
+  store i8 0, i8 addrspace(4)* %p
+  ret void
+}
+
+define void @test_constant32bit_addrspace(i8 addrspace(6)* %p) {
+; CHECK-LABEL: @test_constant32bit_addrspace(
+; CHECK-NEXT:    ret void
+;
+  store i8 0, i8 addrspace(6)* %p
+  ret void
+}
+
+define void @test_cast_generic_from_constant_addrspace(i8 addrspace(4)* %p) {
+; CHECK-LABEL: @test_cast_generic_from_constant_addrspace(
+; CHECK-NEXT:    ret void
+;
+  %cast = addrspacecast i8 addrspace(4)* %p to i8*
+  store i8 0, i8* %cast
+  ret void
+}
+
+define void @test_cast_generic_from_constant32bit_addrspace(i8 addrspace(6)* %p) {
+; CHECK-LABEL: @test_cast_generic_from_constant32bit_addrspace(
+; CHECK-NEXT:    ret void
+;
+  %cast = addrspacecast i8 addrspace(6)* %p to i8*
+  store i8 0, i8* %cast
+  ret void
+}
+
+define void @test_cast_generic_to_constant_addrspace(i8* %p) {
+; CHECK-LABEL: @test_cast_generic_to_constant_addrspace(
+; CHECK-NEXT:    ret void
+;
+  %cast = addrspacecast i8* %p to i8 addrspace(4)*
+  store i8 0, i8 addrspace(4)* %cast
+  ret void
+}
+
+define void @test_cast_generic_to_constant32bit_addrspace(i8* %p) {
+; CHECK-LABEL: @test_cast_generic_to_constant32bit_addrspace(
+; CHECK-NEXT:    ret void
+;
+  %cast = addrspacecast i8* %p to i8 addrspace(6)*
+  store i8 0, i8 addrspace(6)* %cast
+  ret void
+}
+
+define amdgpu_kernel void @noalias_readnone_global_kernarg(i32 addrspace(1)* noalias readnone %arg) {
+; CHECK-LABEL: @noalias_readnone_global_kernarg(
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(1)* %arg
+  ret void
+}
+
+define amdgpu_kernel void @noalias_readonly_global_kernarg(i32 addrspace(1)* noalias readonly %arg) {
+; CHECK-LABEL: @noalias_readonly_global_kernarg(
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(1)* %arg
+  ret void
+}
+
+define amdgpu_kernel void @readnone_global_kernarg(i32 addrspace(1)* readnone %arg) {
+; CHECK-LABEL: @readnone_global_kernarg(
+; CHECK-NEXT:    store i32 0, i32 addrspace(1)* [[ARG:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(1)* %arg
+  ret void
+}
+
+define amdgpu_kernel void @readonly_global_kernarg(i32 addrspace(1)* readonly %arg) {
+; CHECK-LABEL: @readonly_global_kernarg(
+; CHECK-NEXT:    store i32 0, i32 addrspace(1)* [[ARG:%.*]], align 4
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(1)* %arg
+  ret void
+}
+
+@global_as_constant = external addrspace(1) constant i32, align 4
+
+define amdgpu_kernel void @constant_gv_global_as() {
+; CHECK-LABEL: @constant_gv_global_as(
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(1)* @global_as_constant
+  ret void
+}
+
+@global_nonconstant_constant_as = external addrspace(4) global i32, align 4
+
+define amdgpu_kernel void @nonconst_gv_constant_as() {
+; CHECK-LABEL: @nonconst_gv_constant_as(
+; CHECK-NEXT:    ret void
+;
+  store i32 0, i32 addrspace(4)* @global_nonconstant_constant_as
+  ret void
+}