diff --git a/clang/lib/CIR/CodeGen/CIRGenCall.cpp b/clang/lib/CIR/CodeGen/CIRGenCall.cpp
index 10b4528ff2aac..edfc7408c740e 100644
--- a/clang/lib/CIR/CodeGen/CIRGenCall.cpp
+++ b/clang/lib/CIR/CodeGen/CIRGenCall.cpp
@@ -1109,6 +1109,18 @@ RValue CIRGenFunction::emitCall(const CIRGenFunctionInfo &funcInfo,
       if (argType != v.getType() && mlir::isa<cir::IntType>(v.getType()))
         cgm.errorNYI(loc, "emitCall: widening integer call argument");
 
+      // If we have a pointer argument and there's an address space mismatch,
+      // insert an address_space cast to match the expected function signature.
+      if (argType != v.getType()) {
+        auto argPtrTy = mlir::dyn_cast<cir::PointerType>(argType);
+        auto vPtrTy = mlir::dyn_cast<cir::PointerType>(v.getType());
+        if (argPtrTy && vPtrTy &&
+            argPtrTy.getPointee() == vPtrTy.getPointee() &&
+            argPtrTy.getAddrSpace() != vPtrTy.getAddrSpace()) {
+          v = performAddrSpaceCast(v, argPtrTy);
+        }
+      }
+
       // If the argument doesn't match, perform a bitcast to coerce it. This
       // can happen due to trivial type mismatches.
       // TODO(cir): When getFunctionType is added, assert that this isn't
diff --git a/clang/test/CIR/CodeGen/amdgpu-call-addrspace-cast.cpp b/clang/test/CIR/CodeGen/amdgpu-call-addrspace-cast.cpp
new file mode 100644
index 0000000000000..6b98ea10fceac
--- /dev/null
+++ b/clang/test/CIR/CodeGen/amdgpu-call-addrspace-cast.cpp
@@ -0,0 +1,47 @@
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -fclangir -emit-cir %s -o %t.cir
+// RUN: FileCheck --input-file=%t.cir %s -check-prefix=CIR
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -fclangir -emit-llvm %s -o %t.ll
+// RUN: FileCheck --input-file=%t.ll %s -check-prefix=LLVM
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -emit-llvm %s -o %t.ll
+// RUN: FileCheck --input-file=%t.ll %s -check-prefix=OGCG
+
+// Test that address space casts are inserted when passing pointers in
+// non-default address spaces (global AS 1, private AS 5 on AMDGPU) to
+// functions expecting flat (generic) pointers.
+
+int globalVar = 42;
+
+void takes_ptr(int *p);
+
+// CIR-LABEL: cir.func{{.*}} @_Z20call_with_global_ptrv()
+// CIR:         %[[GPTR:.*]] = cir.get_global @globalVar : !cir.ptr<!s32i, target_address_space(1)>
+// CIR-NEXT:    %[[CAST:.*]] = cir.cast address_space %[[GPTR]] : !cir.ptr<!s32i, target_address_space(1)> -> !cir.ptr<!s32i>
+// CIR-NEXT:    cir.call @_Z9takes_ptrPi(%[[CAST]])
+
+// LLVM-LABEL: define{{.*}} void @_Z20call_with_global_ptrv()
+// LLVM:         call void @_Z9takes_ptrPi(ptr noundef addrspacecast (ptr addrspace(1) @globalVar to ptr))
+
+// OGCG-LABEL: define{{.*}} void @_Z20call_with_global_ptrv()
+// OGCG:         call void @_Z9takes_ptrPi(ptr noundef addrspacecast (ptr addrspace(1) @globalVar to ptr))
+void call_with_global_ptr() {
+  takes_ptr(&globalVar);
+}
+
+// CIR-LABEL: cir.func{{.*}} @_Z19call_with_local_ptrv()
+// CIR:         %[[ALLOCA:.*]] = cir.alloca !s32i, !cir.ptr<!s32i, target_address_space(5)>
+// CIR:         %[[CAST:.*]] = cir.cast address_space %[[ALLOCA]] : !cir.ptr<!s32i, target_address_space(5)> -> !cir.ptr<!s32i>
+// CIR-NEXT:    cir.call @_Z9takes_ptrPi(%[[CAST]])
+
+// LLVM-LABEL: define{{.*}} void @_Z19call_with_local_ptrv()
+// LLVM:         %[[ALLOCA:.*]] = alloca i32, i64 1, align 4, addrspace(5)
+// LLVM:         %[[CAST:.*]] = addrspacecast ptr addrspace(5) %[[ALLOCA]] to ptr
+// LLVM-NEXT:    call void @_Z9takes_ptrPi(ptr noundef %[[CAST]])
+
+// OGCG-LABEL: define{{.*}} void @_Z19call_with_local_ptrv()
+// OGCG:         %[[ALLOCA:.*]] = alloca i32, align 4, addrspace(5)
+// OGCG-NEXT:    %[[CAST:.*]] = addrspacecast ptr addrspace(5) %[[ALLOCA]] to ptr
+// OGCG:         call void @_Z9takes_ptrPi(ptr noundef %[[CAST]])
+void call_with_local_ptr() {
+  int x = 1;
+  takes_ptr(&x);
+}