[CUDA][HIP] Fix gpu.used.external

Rename gpu.used.external as __clang_gpu_used_external as ptxas does not
allow . in global variable name.

Fixes: llvm#54934

Reviewed by: Joseph Huber, Artem Belevich

Differential Revision: https://reviews.llvm.org/D123946

Author: yxsamliu

clang/lib/CodeGen/CodeGenModule.cpp

@@ -599,7 +599,7 @@ void CodeGenModule::Release() {
 
     auto *GV = new llvm::GlobalVariable(
         getModule(), ATy, false, llvm::GlobalValue::AppendingLinkage,
-        llvm::ConstantArray::get(ATy, UsedArray), "gpu.used.external");
+        llvm::ConstantArray::get(ATy, UsedArray), "__clang_gpu_used_external");
     addCompilerUsedGlobal(GV);
   }
 

clang/test/CodeGenCUDA/host-used-extern.cu

@@ -11,19 +11,19 @@
 
 #include "Inputs/cuda.h"
 
-// CHECK-LABEL: @gpu.used.external = appending {{.*}}global
+// CHECK-LABEL: @__clang_gpu_used_external = appending {{.*}}global
 // CHECK-DAG: @_Z7kernel1v
 // CHECK-DAG: @_Z7kernel4v
 // CHECK-DAG: @var1
-// CHECK-LABEL: @llvm.compiler.used = {{.*}} @gpu.used.external
-
-// NEG-NOT: @gpu.used.external = {{.*}} @_Z7kernel2v
-// NEG-NOT: @gpu.used.external = {{.*}} @_Z7kernel3v
-// NEG-NOT: @gpu.used.external = {{.*}} @var2
-// NEG-NOT: @gpu.used.external = {{.*}} @var3
-// NORDC-NOT: @gpu.used.external = {{.*}} @_Z7kernel1v
-// NORDC-NOT: @gpu.used.external = {{.*}} @_Z7kernel4v
-// NORDC-NOT: @gpu.used.external = {{.*}} @var1
+// CHECK-LABEL: @llvm.compiler.used = {{.*}} @__clang_gpu_used_external
+
+// NEG-NOT: @__clang_gpu_used_external = {{.*}} @_Z7kernel2v
+// NEG-NOT: @__clang_gpu_used_external = {{.*}} @_Z7kernel3v
+// NEG-NOT: @__clang_gpu_used_external = {{.*}} @var2
+// NEG-NOT: @__clang_gpu_used_external = {{.*}} @var3
+// NORDC-NOT: @__clang_gpu_used_external = {{.*}} @_Z7kernel1v
+// NORDC-NOT: @__clang_gpu_used_external = {{.*}} @_Z7kernel4v
+// NORDC-NOT: @__clang_gpu_used_external = {{.*}} @var1
 
 __global__ void kernel1();