[clang] [NVPTX][AMDGPU][CodeGen] Fix `local_space nullptr` handling for NVPTX and local/private `nullptr` value for AMDGPU. (PR #78759)

[via cfe-commits]

================
@@ -0,0 +1,122 @@
+// RUN: %clang_cc1 -triple nvptx64-nvidia-cuda -fsycl-is-device -disable-llvm-passes -emit-llvm %s -o - | FileCheck %s
+void bar(int &Data) {}
+// CHECK-DAG: define dso_local void @[[RAW_REF:[a-zA-Z0-9_]+]](ptr noundef nonnull align 4 dereferenceable(4) %
+void bar2(int &Data) {}
+// CHECK-DAG: define dso_local void @[[RAW_REF2:[a-zA-Z0-9_]+]](ptr noundef nonnull align 4 dereferenceable(4) %
+void bar(__attribute__((opencl_local)) int &Data) {}
+// CHECK-DAG: define dso_local void @[[LOCAL_REF:[a-zA-Z0-9_]+]](ptr addrspace(3) noundef align 4 dereferenceable(4) %
+void foo(int *Data) {}
+// CHECK-DAG: define dso_local void @[[RAW_PTR:[a-zA-Z0-9_]+]](ptr noundef %
+void foo2(int *Data) {}
+// CHECK-DAG: define dso_local void @[[RAW_PTR2:[a-zA-Z0-9_]+]](ptr noundef %
+void foo(__attribute__((opencl_local)) int *Data) {}
+// CHECK-DAG: define dso_local void @[[LOC_PTR:[a-zA-Z0-9_]+]](ptr addrspace(3) noundef %
+
+template <typename T>
+void tmpl(T t);
+// See Check Lines below.
+
+void usages() {
+  __attribute__((opencl_global)) int *GLOB;
+  // CHECK-DAG: [[GLOB:%[a-zA-Z0-9]+]] = alloca ptr addrspace(1), align 8
+  __attribute__((opencl_local)) int *LOC;
+  // CHECK-DAG: [[LOC:%[a-zA-Z0-9]+]] = alloca ptr addrspace(3), align 8
+  LOC = nullptr;
+  // CHECK-DAG: store ptr addrspace(3) addrspacecast (ptr null to ptr addrspace(3)), ptr [[LOC]], align 8
+  GLOB = nullptr;
+  // CHECK-DAG: store ptr addrspace(1) null, ptr [[GLOB]], align 8
+  int *NoAS;
+  // CHECK-DAG: [[NoAS:%[a-zA-Z0-9]+]] = alloca ptr, align 8
+  __attribute__((opencl_private)) int *PRIV;
+  // CHECK-DAG: [[PRIV:%[a-zA-Z0-9]+]] = alloca ptr, align 8
+  __attribute__((opencl_global_device)) int *GLOBDEVICE;
+  // CHECK-DAG: [[GLOB_DEVICE:%[a-zA-Z0-9]+]] = alloca ptr addrspace(1), align 8
+  __attribute__((opencl_global_host)) int *GLOBHOST;
+  // CHECK-DAG: [[GLOB_HOST:%[a-zA-Z0-9]+]] = alloca ptr addrspace(1), align 8
+  NoAS = (int *)GLOB;
+  // CHECK-DAG: [[GLOB_LOAD:%[a-zA-Z0-9]+]] = load ptr addrspace(1), ptr [[GLOB]], align 8
+  // CHECK-DAG: [[GLOB_CAST:%[a-zA-Z0-9]+]] = addrspacecast ptr addrspace(1) [[GLOB_LOAD]] to ptr
+  // CHECK-DAG: store ptr [[GLOB_CAST]], ptr [[NoAS]], align 8
+  NoAS = (int *)LOC;
+  // CHECK-DAG: [[LOC_LOAD:%[a-zA-Z0-9]+]] = load ptr addrspace(3), ptr [[LOC]], align 8
+  // CHECK-DAG: [[LOC_CAST:%[a-zA-Z0-9]+]] = addrspacecast ptr addrspace(3) [[LOC_LOAD]] to ptr
+  // CHECK-DAG: store ptr [[LOC_CAST]], ptr [[NoAS]], align 8
+  NoAS = (int *)PRIV;
+  // CHECK-DAG: [[LOC_LOAD:%[a-zA-Z0-9]+]] = load ptr, ptr [[PRIV]], align 8
+  // CHECK-DAG: store ptr [[LOC_LOAD]], ptr [[NoAS]], align 8
+  GLOB = (__attribute__((opencl_global)) int *)NoAS;
+  // CHECK-DAG: [[NoAS_LOAD:%[a-zA-Z0-9]+]] = load ptr, ptr [[NoAS]], align 8
+  // CHECK-DAG: [[NoAS_CAST:%[a-zA-Z0-9]+]] = addrspacecast ptr [[NoAS_LOAD]] to ptr addrspace(1)
+  // CHECK-DAG: store ptr addrspace(1) [[NoAS_CAST]], ptr [[GLOB]], align 8
+  LOC = (__attribute__((opencl_local)) int *)NoAS;
+  // CHECK-DAG: [[NoAS_LOAD:%[a-zA-Z0-9]+]] = load ptr, ptr [[NoAS]], align 8
+  // CHECK-DAG: [[NoAS_CAST:%[a-zA-Z0-9]+]] = addrspacecast ptr [[NoAS_LOAD]] to ptr addrspace(3)
+  // CHECK-DAG: store ptr addrspace(3) [[NoAS_CAST]], ptr [[LOC]], align 8
+  PRIV = (__attribute__((opencl_private)) int *)NoAS;
+  // CHECK-DAG: [[NoAS_LOAD:%[a-zA-Z0-9]+]] = load ptr, ptr [[NoAS]], align 8
+  // CHECK-DAG: store ptr [[NoAS_LOAD]], ptr [[PRIV]], align 8
+  GLOB = (__attribute__((opencl_global)) int *)GLOBDEVICE;
+  // CHECK-DAG: [[GLOBDEVICE_LOAD:%[a-zA-Z0-9]+]] = load ptr addrspace(1), ptr [[GLOB_DEVICE]], align 8
+  // CHECK-DAG: store ptr addrspace(1) [[GLOBDEVICE_LOAD]], ptr %GLOB, align 8
+  GLOB = (__attribute__((opencl_global)) int *)GLOBHOST;
+  // CHECK-DAG: [[GLOB_HOST_LOAD:%[a-zA-Z0-9]+]] = load ptr addrspace(1), ptr [[GLOB_HOST]], align 8
+  // CHECK-DAG: store ptr addrspace(1) [[GLOB_HOST_LOAD]], ptr [[GLOB]], align 8
+  bar(*GLOB);
----------------
mmoadeli wrote:

Thanks @arichardson in added AMD and CUDA tests `CHECK-DAG`s are replaced with `CHECK`. 

https://github.com/llvm/llvm-project/pull/78759