Subzero: Add a few performance measurement tools.

src/IceConverter.cpp

Index: src/IceConverter.cpp
diff --git a/src/IceConverter.cpp b/src/IceConverter.cpp
index df64cff9ab92db0510b3630fac16f60a81c98cea..42dec12f05149723e3f528845bead218fd7b7e4d 100644
--- a/src/IceConverter.cpp
+++ b/src/IceConverter.cpp
@@ -61,13 +61,13 @@ public:
   Ice::Cfg *convertFunction(const Function *F) {
     static Ice::TimerIdT IDllvmConvert =
         Ice::GlobalContext::getTimerID("llvmConvert");
-    Ice::TimerMarker T(IDllvmConvert, Ctx);
     VarMap.clear();
     NodeMap.clear();
     Func = new Ice::Cfg(Ctx);
     Func->setFunctionName(F->getName());
     Func->setReturnType(convertToIceType(F->getReturnType()));
     Func->setInternal(F->hasInternalLinkage());
+    Ice::TimerMarker T(IDllvmConvert, Func);
 
     // The initial definition/use of each arg is the entry node.
     for (auto ArgI = F->arg_begin(), ArgE = F->arg_end(); ArgI != ArgE;
@@ -626,13 +626,18 @@ void Converter::convertToIce() {
 }
 
 void Converter::convertFunctions() {
+  TimerStackIdT StackID = GlobalContext::TSK_Funcs;
   for (const Function &I : *Mod) {
     if (I.empty())
       continue;
+    if (Ctx->getFlags().TimeEachFunction)
+      Ctx->pushTimer(GlobalContext::getTimerID(I.getName()), StackID);
     LLVM2ICEConverter FunctionConverter(Ctx, Mod->getContext());
 
     Cfg *Fcn = FunctionConverter.convertFunction(&I);
     translateFcn(Fcn);
+    if (Ctx->getFlags().TimeEachFunction)
+      Ctx->popTimer(GlobalContext::getTimerID(I.getName()), StackID);
   }
 
   emitConstants();