Add explicit keywords.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48801 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86InstrInfo.h b/lib/Target/X86/X86InstrInfo.h
index f4cdb70..111eb8c 100644
--- a/lib/Target/X86/X86InstrInfo.h
+++ b/lib/Target/X86/X86InstrInfo.h
@@ -243,7 +243,7 @@
   DenseMap<unsigned*, std::pair<unsigned, unsigned> > MemOp2RegOpTable;
   
 public:
-  X86InstrInfo(X86TargetMachine &tm);
+  explicit X86InstrInfo(X86TargetMachine &tm);
 
   /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info.  As
   /// such, whenever a client has an instance of instruction info, it should