Add Triple::isAMDGPU

[yaxunl]

Summary

I have been bothered by missing Triple::isAMDGPU for long time. There is isNVPTX, isARM,
why can't we have isAMDGPU?

[rampitec]

LGTM

[arsenm]

Needs unit test

[yaxunl]

add usage of it

[yaxunl]

In D57707#1383819, @arsenm wrote:

Needs unit test

I used it in TargetLibraryInfo.cpp. We have lit tests cover them, so they also cover this function.

llvm/include/llvm/ADT/Triple.h

bool isSPIR() const {
     return getArch() == Triple::spir || getArch() == Triple::spir64;
   }
 
   /// Tests whether the target is NVPTX (32- or 64-bit).
   bool isNVPTX() const {
     return getArch() == Triple::nvptx || getArch() == Triple::nvptx64;
   }
 
+  bool isAMDGPU() const {
+    return getArch() == Triple::r600 || getArch() == Triple::amdgcn;
+  }
+
   /// Tests whether the target is Thumb (little and big endian).
   bool isThumb() const {
     return getArch() == Triple::thumb || getArch() == Triple::thumbeb;
   }
 
   /// Tests whether the target is ARM (little and big endian).
   bool isARM() const {
     return getArch() == Triple::arm || getArch() == Triple::armeb;

llvm/lib/Analysis/TargetLibraryInfo.cpp

static void initialize(TargetLibraryInfoImpl &TLI, const Triple &T,
   // to both signed and unsigned ints.
   if (T.isMIPS()) {
     ShouldSignExtI32Param = true;
   }
   TLI.setShouldExtI32Param(ShouldExtI32Param);
   TLI.setShouldExtI32Return(ShouldExtI32Return);
   TLI.setShouldSignExtI32Param(ShouldSignExtI32Param);
 
-  if (T.getArch() == Triple::r600 ||
-      T.getArch() == Triple::amdgcn)
+  if (T.isAMDGPU())
     TLI.disableAllFunctions();
 
   // There are no library implementations of memcpy and memset for AMD gpus and
   // these can be difficult to lower in the backend.
-  if (T.getArch() == Triple::r600 ||
-      T.getArch() == Triple::amdgcn) {
+  if (T.isAMDGPU()) {
     TLI.setUnavailable(LibFunc_memcpy);
     TLI.setUnavailable(LibFunc_memset);
     TLI.setUnavailable(LibFunc_memset_pattern16);
     return;
   }
 
   // memset_pattern16 is only available on iOS 3.0 and Mac OS X 10.5 and later.
   // All versions of watchOS support it.