diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineCombiner.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineCombiner.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/MachineCombiner.cpp b/llvm/lib/CodeGen/MachineCombiner.cpp index b4e217c4815..54c4741e6fa 100644 --- a/llvm/lib/CodeGen/MachineCombiner.cpp +++ b/llvm/lib/CodeGen/MachineCombiner.cpp @@ -71,6 +71,7 @@ private: improvesCriticalPathLen(MachineBasicBlock *MBB, MachineInstr *Root, MachineTraceMetrics::Trace BlockTrace, SmallVectorImpl<MachineInstr *> &InsInstrs, + SmallVectorImpl<MachineInstr *> &DelInstrs, DenseMap<unsigned, unsigned> &InstrIdxForVirtReg, MachineCombinerPattern Pattern); bool preservesResourceLen(MachineBasicBlock *MBB, @@ -242,6 +243,7 @@ bool MachineCombiner::improvesCriticalPathLen( MachineBasicBlock *MBB, MachineInstr *Root, MachineTraceMetrics::Trace BlockTrace, SmallVectorImpl<MachineInstr *> &InsInstrs, + SmallVectorImpl<MachineInstr *> &DelInstrs, DenseMap<unsigned, unsigned> &InstrIdxForVirtReg, MachineCombinerPattern Pattern) { assert(TSchedModel.hasInstrSchedModelOrItineraries() && @@ -269,8 +271,13 @@ bool MachineCombiner::improvesCriticalPathLen( // A more flexible cost calculation for the critical path includes the slack // of the original code sequence. This may allow the transform to proceed // even if the instruction depths (data dependency cycles) become worse. + unsigned NewRootLatency = getLatency(Root, NewRoot, BlockTrace); - unsigned RootLatency = TSchedModel.computeInstrLatency(Root); + unsigned RootLatency = 0; + + for (auto I : DelInstrs) + RootLatency += TSchedModel.computeInstrLatency(I); + unsigned RootSlack = BlockTrace.getInstrSlack(*Root); DEBUG(dbgs() << " NewRootLatency: " << NewRootLatency << "\n"; @@ -421,7 +428,7 @@ bool MachineCombiner::combineInstructions(MachineBasicBlock *MBB) { // resource pressure. if (SubstituteAlways || doSubstitute(NewInstCount, OldInstCount) || (improvesCriticalPathLen(MBB, &MI, BlockTrace, InsInstrs, - InstrIdxForVirtReg, P) && + DelInstrs, InstrIdxForVirtReg, P) && preservesResourceLen(MBB, BlockTrace, InsInstrs, DelInstrs))) { for (auto *InstrPtr : InsInstrs) MBB->insert((MachineBasicBlock::iterator) &MI, InstrPtr); |
