Compute feature bits at time of MCSubtargetInfo initialization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134606 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsSubtarget.h b/lib/Target/Mips/MipsSubtarget.h
index ae76470..533d4af 100644
--- a/lib/Target/Mips/MipsSubtarget.h
+++ b/lib/Target/Mips/MipsSubtarget.h
@@ -22,6 +22,7 @@
 #include "MipsGenSubtargetInfo.inc"
 
 namespace llvm {
+class StringRef;
 
 class MipsSubtarget : public MipsGenSubtargetInfo {
 
@@ -99,7 +100,7 @@
 
   /// ParseSubtargetFeatures - Parses features string setting specified
   /// subtarget options.  Definition of function is auto generated by tblgen.
-  void ParseSubtargetFeatures(const std::string &FS, const std::string &CPU);
+  void ParseSubtargetFeatures(StringRef CPU, StringRef FS);
 
   bool isMips1() const { return MipsArchVersion == Mips1; }
   bool isMips32() const { return MipsArchVersion >= Mips32; }