diff --git a/llvm/lib/Target/Mips/MipsSubtarget.cpp b/llvm/lib/Target/Mips/MipsSubtarget.cpp
index 8f5ecad..b301649 100644
--- a/llvm/lib/Target/Mips/MipsSubtarget.cpp
+++ b/llvm/lib/Target/Mips/MipsSubtarget.cpp
@@ -59,9 +59,8 @@
 
 void MipsSubtarget::anchor() { }
 
-MipsSubtarget::MipsSubtarget(const Triple &TT, const std::string &CPU,
-                             const std::string &FS, bool little,
-                             const MipsTargetMachine &TM)
+MipsSubtarget::MipsSubtarget(const Triple &TT, StringRef CPU, StringRef FS,
+                             bool little, const MipsTargetMachine &TM)
     : MipsGenSubtargetInfo(TT, CPU, FS), MipsArchVersion(MipsDefault),
       IsLittle(little), IsSoftFloat(false), IsSingleFloat(false), IsFPXX(false),
       NoABICalls(false), IsFP64bit(false), UseOddSPReg(true),