Add Triple::isSPIR() to simplify code

[Anastasia]

LGTM! Thanks!

llvm/trunk/include/llvm/ADT/Triple.h

public:
 
   /// Tests whether the environment is musl-libc
   bool isMusl() const {
     return getEnvironment() == Triple::Musl ||
            getEnvironment() == Triple::MuslEABI ||
            getEnvironment() == Triple::MuslEABIHF;
   }
 
+  /// Tests whether the target is SPIR (32- or 64-bit).
+  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;
   }
 
   /// Tests whether the target is Thumb (little and big endian).
   bool isThumb() const {
     return getArch() == Triple::thumb || getArch() == Triple::thumbeb;