Cache common constants before lowering.

src/IceTargetLowering.cpp

Index: src/IceTargetLowering.cpp
diff --git a/src/IceTargetLowering.cpp b/src/IceTargetLowering.cpp
index 2208753f9f094358dfe20da93441ff27c72544c2..6a6eabf66f7f14619337c312ddd225c9eb9700bb 100644
--- a/src/IceTargetLowering.cpp
+++ b/src/IceTargetLowering.cpp
@@ -697,10 +697,10 @@ void TargetLowering::assignVarStackSlots(VarList &SortedSpilledVariables,
   }
 }
 
-InstCall *TargetLowering::makeHelperCall(const IceString &Name, Variable *Dest,
-                                         SizeT MaxSrcs) {
+InstCall *TargetLowering::makeHelperCall(RuntimeHelperFuncID FuncID,
+                                         Variable *Dest, SizeT MaxSrcs) {
   constexpr bool HasTailCall = false;
-  Constant *CallTarget = Ctx->getConstantExternSym(Name);
+  Operand *CallTarget = getRuntimeHelperFunc(FuncID);

[Jim Stichnoth, 2016/03/17 00:14:52]

Keep this as Constant* ?

[John, 2016/03/17 14:31:33]

<joking message='did anyway say "auto *"? :)' />

[Karl, 2016/03/17 16:40:53]

Changed to "Constant *".

   InstCall *Call =
       InstCall::create(Func, MaxSrcs, Dest, CallTarget, HasTailCall);
   return Call;