Dramatically simplify how -time-passes works.

This also enables -time-passes for FunctionPassManagers, which allows it to
be used for the JIT


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7834 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 24 insertions, 62 deletions

diff --git a/lib/VMCore/Pass.cpp b/lib/VMCore/Pass.cpp
index 6535d10467..711b6108a1 100644
--- a/lib/VMCore/Pass.cpp
+++ b/lib/VMCore/Pass.cpp
@@ -90,11 +90,17 @@ static cl::opt<bool>
 EnableTiming("time-passes",
             cl::desc("Time each pass, printing elapsed time for each on exit"));
 
-// Create method.  If Timing is enabled, this creates and returns a new timing
-// object, otherwise it returns null.
-//
-TimingInfo *TimingInfo::create() {
-  return EnableTiming ? new TimingInfo() : 0;
+// createTheTimeInfo - This method either initializes the TheTimeInfo pointer to
+// a non null value (if the -time-passes option is enabled) or it leaves it
+// null.  It may be called multiple times.
+void TimingInfo::createTheTimeInfo() {
+  if (!EnableTiming || TheTimeInfo) return;
+
+  // Constructed the first time this is called, iff -time-passes is enabled.
+  // This guarantees that the object will be constructed before static globals,
+  // thus it will be destroyed before them.
+  static TimingInfo TTI;
+  TheTimeInfo = &TTI;
 }
 
 void PMDebug::PrintArgumentInformation(const Pass *P) {
diff --git a/lib/VMCore/PassManagerT.h b/lib/VMCore/PassManagerT.h
index 85d7e6b7e0..5ccb76751b 100644
--- a/lib/VMCore/PassManagerT.h
+++ b/lib/VMCore/PassManagerT.h
@@ -84,11 +84,6 @@ class TimingInfo {
   // Private ctor, must use 'create' member
   TimingInfo() : TG("... Pass execution timing report ...") {}
 public:
-  // Create method.  If Timing is enabled, this creates and returns a new timing
-  // object, otherwise it returns null.
-  //
-  static TimingInfo *create();
-
   // TimingDtor - Print out information about timing information
   ~TimingInfo() {
     // Delete all of the timers...
@@ -96,6 +91,11 @@ public:
     // TimerGroup is deleted next, printing the report.
   }
 
+  // createTheTimeInfo - This method either initializes the TheTimeInfo pointer
+  // to a non null value (if the -time-passes option is enabled) or it leaves it
+  // null.  It may be called multiple times.
+  static void createTheTimeInfo();
+
   void passStarted(Pass *P) {
     if (dynamic_cast<AnalysisResolver*>(P)) return;
     std::map<Pass*, Timer>::iterator I = TimingData.find(P);
@@ -111,6 +111,8 @@ public:
   }
 };
 
+static TimingInfo *TheTimeInfo;
+
 //===----------------------------------------------------------------------===//
 // Declare the PassManagerTraits which will be specialized...
 //
@@ -176,6 +178,8 @@ public:
     closeBatcher();
     CurrentAnalyses.clear();
 
+    TimingInfo::createTheTimeInfo();
+
     // Add any immutable passes to the CurrentAnalyses set...
     for (unsigned i = 0, e = ImmutablePasses.size(); i != e; ++i) {
       ImmutablePass *IPass = ImmutablePasses[i];
@@ -235,9 +239,9 @@ public:
       }
 
       // Run the sub pass!
-      startPass(P);
+      if (TheTimeInfo) TheTimeInfo->passStarted(P);
       bool Changed = runPass(P, M);
-      endPass(P);
+      if (TheTimeInfo) TheTimeInfo->passEnded(P);
       MadeChanges |= Changed;
 
       // Check for memory leaks by the pass...
@@ -305,6 +309,7 @@ public:
         }
       }
     }
+
     return MadeChanges;
   }
 
@@ -375,20 +380,6 @@ public:
     return 0;
   }
 
-  // {start/end}Pass - Called when a pass is started, it just propagates
-  // information up to the top level PassManagerT object to tell it that a pass
-  // has started or ended.  This is used to gather timing information about
-  // passes.
-  //
-  void startPass(Pass *P) {
-    if (Parent) Parent->startPass(P);
-    else PassStarted(P);
-  }
-  void endPass(Pass *P) {
-    if (Parent) Parent->endPass(P);
-    else PassEnded(P);
-  }
-
   // markPassUsed - Inform higher level pass managers (and ourselves)
   // that these analyses are being used by this pass.  This is used to
   // make sure that analyses are not free'd before we have to use
@@ -619,10 +610,6 @@ template<> struct PassManagerTraits<BasicBlock> : public BasicBlockPass {
     return P->runOnBasicBlock(*M);
   }
 
-  // Dummy implementation of PassStarted/PassEnded
-  static void PassStarted(Pass *P) {}
-  static void PassEnded(Pass *P) {}
-
   // getPMName() - Return the name of the unit the PassManager operates on for
   // debugging.
   const char *getPMName() const { return "BasicBlock"; }
@@ -669,10 +656,6 @@ template<> struct PassManagerTraits<Function> : public FunctionPass {
     return P->runOnFunction(*F);
   }
 
-  // Dummy implementation of PassStarted/PassEnded
-  static void PassStarted(Pass *P) {}
-  static void PassEnded(Pass *P) {}
-
   // getPMName() - Return the name of the unit the PassManager operates on for
   // debugging.
   const char *getPMName() const { return "Function"; }
@@ -716,37 +699,10 @@ template<> struct PassManagerTraits<Module> : public Pass {
   const char *getPMName() const { return "Module"; }
   virtual const char *getPassName() const { return "Module Pass Manager"; }
 
-  // TimingInformation - This data member maintains timing information for each
-  // of the passes that is executed.
-  //
-  TimingInfo *TimeInfo;
-
-  // PassStarted/Ended - This callback is notified any time a pass is started
-  // or stops.  This is used to collect timing information about the different
-  // passes being executed.
-  //
-  void PassStarted(Pass *P) {
-    if (TimeInfo) TimeInfo->passStarted(P);
-  }
-  void PassEnded(Pass *P) {
-    if (TimeInfo) TimeInfo->passEnded(P);
-  }
-
   // run - Implement the PassManager interface...
   bool run(Module &M) {
-    TimeInfo = TimingInfo::create();
-    bool Result = ((PassManagerT<Module>*)this)->runOnUnit(&M);
-    if (TimeInfo) {
-      delete TimeInfo;
-      TimeInfo = 0;
-    }
-    return Result;
+    return ((PassManagerT<Module>*)this)->runOnUnit(&M);
   }
-
-  // PassManagerTraits constructor - Create a timing info object if the user
-  // specified timing info should be collected on the command line.
-  //
-  PassManagerTraits() : TimeInfo(0) {}
 };