Subzero: Rewrite the pass timing infrastructure.

src/IceOperand.cpp

 //===- subzero/src/IceOperand.cpp - High-level operand implementation -----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the Operand class and its target-independent
@@ skipping 104 matching lines @@
     if (I2->second <= I1->first) {
       ++I2;
       continue;
     }
     return true;
   }
   return false;
 }
 
 bool LiveRange::overlaps(InstNumberT OtherBegin) const {
+  bool Result = false;
+  for (RangeType::const_iterator I = Range.begin(), E = Range.end(); I != E;
+       ++I) {
+    if (OtherBegin < I->first) {
+      Result = false;
+      break;
+    }
+    if (OtherBegin < I->second) {
+      Result = true;
+      break;
+    }
+  }
+#if 0
+  // An equivalent but less inefficient implementation:

[Jim Stichnoth, 2014/09/30 22:46:00]

Actual comparisons indicated this was a lie.

The optimized implementation was completely broken.

For now, I'd like to keep this validation code around and paranoically enable it
at the first sign of suspicion.

   LiveRange Temp;
   Temp.addSegment(OtherBegin, OtherBegin + 1);
-  return overlaps(Temp);
+  bool Validation = overlaps(Temp);
+  assert(Result == Validation);
+#endif
+  return Result;
 }
 
 // Returns true if the live range contains the given instruction
 // number.  This is only used for validating the live range
 // calculation.
 bool LiveRange::containsValue(InstNumberT Value) const {
   for (RangeType::const_iterator I = Range.begin(), E = Range.end(); I != E;
        ++I) {
     if (I->first <= Value && Value <= I->second)
       return true;
@@ skipping 114 matching lines @@
   case MDS_MultiDefMultiBlock:
   case MDS_MultiDefSingleBlock:
     return NULL;
   case MDS_SingleDef:
     assert(!Definitions.empty());
     return Definitions[0];
   }
 }
 
 void VariablesMetadata::init() {
+  static TimerIdT IDvmetadata = GlobalContext::getTimerID("vmetadata");
+  TimerMarker T(IDvmetadata, Func->getContext());
   Metadata.clear();
   Metadata.resize(Func->getNumVariables());
 
   // Mark implicit args as being used in the entry node.
   const VarList &ImplicitArgList = Func->getImplicitArgs();
   for (VarList::const_iterator I = ImplicitArgList.begin(),
                                E = ImplicitArgList.end();
        I != E; ++I) {
     const Variable *Var = *I;
     const Inst *NoInst = NULL;
@@ skipping 164 matching lines @@
 
 Ostream &operator<<(Ostream &Str, const RegWeight &W) {
   if (W.getWeight() == RegWeight::Inf)
     Str << "Inf";
   else
     Str << W.getWeight();
   return Str;
 }
 
 } // end of namespace Ice