Subzero: Add a few performance measurement tools.

src/IceGlobalContext.cpp

Index: src/IceGlobalContext.cpp
diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index 7ea7e5dd02d10eaa64310926fb54b3cc9d3d4efc..02c8f089d44ed7d04feb9b1ca33109d7ad6b73c3 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -119,7 +119,7 @@ GlobalContext::GlobalContext(llvm::raw_ostream *OsDump,
     : StrDump(OsDump), StrEmit(OsEmit), VMask(Mask),
       ConstPool(new ConstantPool()), Arch(Arch), Opt(Opt),
       TestPrefix(TestPrefix), Flags(Flags), HasEmittedFirstMethod(false),
-      RNG(""), Timers(new TimerStack("main")) {}
+      RNG("") {}
 
 // Scan a string for S[0-9A-Z]*_ patterns and replace them with
 // S<num>_ where <num> is the next base-36 value.  If a type name
@@ -385,9 +385,20 @@ TimerIdT GlobalContext::getTimerID(const IceString &Name) {
   return TimerStack::getTimerID(Name);
 }
 
-void GlobalContext::pushTimer(TimerIdT ID) { Timers->push(ID); }
+TimerStackIdT GlobalContext::NumTimerStackIds = GlobalContext::TSK_Num;
 
-void GlobalContext::popTimer(TimerIdT ID) { Timers->pop(ID); }
+TimerStackIdT GlobalContext::getTimerStackID() { return NumTimerStackIds++; }
+
+void GlobalContext::pushTimer(TimerIdT ID, TimerStackIdT StackID) {
+  if (Timers.size() <= StackID)
+    Timers.resize(StackID + 1);
+  Timers[StackID].push(ID);
+}
+
+void GlobalContext::popTimer(TimerIdT ID, TimerStackIdT StackID) {
+  assert(Timers.size() > StackID);
+  Timers[StackID].pop(ID);
+}
 
 void GlobalContext::dumpStats(const IceString &Name, bool Final) {
   if (Flags.DumpStats) {
@@ -400,6 +411,16 @@ void GlobalContext::dumpStats(const IceString &Name, bool Final) {
   }
 }
 
-void GlobalContext::dumpTimers() { Timers->dump(getStrDump()); }
+void GlobalContext::dumpTimers(TimerStackIdT StackID, bool DumpCumulative) {
+  assert(Timers.size() > StackID);
+  Timers[StackID].dump(getStrDump(), DumpCumulative);

[jvoung (off chromium), 2014/10/06 16:30:56]

Maybe the dump() can indicate which StackID the dump is for? Right now it should
be obvious which stack it's for though, based on the timer names (pass names vs
function names).

[Jim Stichnoth, 2014/10/06 21:29:57]

Done.

+}
+
+TimerMarker::TimerMarker(TimerIdT ID, const Cfg *Func)
+    : ID(ID), Ctx(Func->getContext()),
+      Active(Func->getFocusedTiming() || Ctx->getFlags().SubzeroTimingEnabled) {
+  if (Active)
+    Ctx->pushTimer(ID);
+}
 
 } // end of namespace Ice