Use NVPTXTargetInfo for arch info

Author: jchlanda

clang/lib/Basic/Targets/NVPTX.h

@@ -181,6 +181,8 @@ class LLVM_LIBRARY_VISIBILITY NVPTXTargetInfo : public TargetInfo {
 
   bool hasBitIntType() const override { return true; }
   bool hasBFloat16Type() const override { return true; }
+
+  CudaArch getGPU() const { return GPU; }
 };
 } // namespace targets
 } // namespace clang

clang/lib/Sema/SemaDeclAttr.cpp

@@ -10,6 +10,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "../Basic/Targets/NVPTX.h"
 #include "clang/AST/ASTConsumer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/ASTMutationListener.h"
@@ -5609,17 +5610,9 @@ bool Sema::CheckRegparmAttr(const ParsedAttr &AL, unsigned &numParams) {
 
 // Helper to get CudaArch.
 static CudaArch getCudaArch(const TargetInfo &TI) {
-  if (!TI.hasFeature("ptx")) {
-    return CudaArch::UNKNOWN;
-  }
-  for (const auto &Feature : TI.getTargetOpts().FeatureMap) {
-    if (Feature.getValue()) {
-      CudaArch Arch = StringToCudaArch(Feature.getKey());
-      if (Arch != CudaArch::UNKNOWN)
-        return Arch;
-    }
-  }
-  return CudaArch::UNKNOWN;
+  if (!TI.getTriple().isNVPTX())
+    llvm_unreachable("getCudaArch is only valid for NVPTX triple");
+  return static_cast<const targets::NVPTXTargetInfo *>(&TI)->getGPU();
 }
 
 // Checks whether an argument of launch_bounds attribute is