From f392e88e18c54ab6aa086926e68c417741697311 Mon Sep 17 00:00:00 2001 From: Michael Gottesman Date: Sat, 14 Dec 2013 00:53:32 +0000 Subject: [PATCH] [block-freq] Refactor LiveInterals::getSpillWeight to use the new MachineBlockFrequencyInfo methods. This is slightly more interesting than the previous batch of changes. Specifically: 1. We refactor getSpillWeight to take a MachineBlockFrequencyInfo (MBFI) object. This enables us to completely encapsulate the actual manner we use the MachineBlockFrequencyInfo to get our spill weights. This yields cleaner code since one does not need to fetch the actual block frequency before getting the spill weight if all one wants it the spill weight. It also gives us access to entry frequency which we need for our computation. 2. Instead of having getSpillWeight take a MachineBasicBlock (as one might think) to look up the block frequency via the MBFI object, we instead take in a MachineInstr object. The reason for this is that the method is supposed to return the spill weight for an instruction according to the comments around the function. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@197296 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/CodeGen/LiveIntervalAnalysis.h | 5 ++++- lib/CodeGen/CalcSpillWeights.cpp | 2 +- lib/CodeGen/LiveIntervalAnalysis.cpp | 10 +++++++--- lib/CodeGen/RegAllocPBQP.cpp | 3 +-- lib/CodeGen/StackSlotColoring.cpp | 3 +-- 5 files changed, 14 insertions(+), 9 deletions(-) diff --git a/include/llvm/CodeGen/LiveIntervalAnalysis.h b/include/llvm/CodeGen/LiveIntervalAnalysis.h index d8437f09aaa..74e47413d8e 100644 --- a/include/llvm/CodeGen/LiveIntervalAnalysis.h +++ b/include/llvm/CodeGen/LiveIntervalAnalysis.h @@ -45,6 +45,7 @@ namespace llvm { class TargetInstrInfo; class TargetRegisterClass; class VirtRegMap; + class MachineBlockFrequencyInfo; class LiveIntervals : public MachineFunctionPass { MachineFunction* MF; @@ -100,7 +101,9 @@ namespace llvm { virtual ~LiveIntervals(); // Calculate the spill weight to assign to a single instruction. - static float getSpillWeight(bool isDef, bool isUse, BlockFrequency freq); + static float getSpillWeight(bool isDef, bool isUse, + const MachineBlockFrequencyInfo *MBFI, + const MachineInstr *Instr); LiveInterval &getInterval(unsigned Reg) { if (hasInterval(Reg)) diff --git a/lib/CodeGen/CalcSpillWeights.cpp b/lib/CodeGen/CalcSpillWeights.cpp index 4925c4db1e0..1a45de069ea 100644 --- a/lib/CodeGen/CalcSpillWeights.cpp +++ b/lib/CodeGen/CalcSpillWeights.cpp @@ -132,7 +132,7 @@ VirtRegAuxInfo::calculateSpillWeightAndHint(LiveInterval &li) { bool reads, writes; tie(reads, writes) = mi->readsWritesVirtualRegister(li.reg); weight = LiveIntervals::getSpillWeight( - writes, reads, MBFI.getBlockFreq(mi->getParent())); + writes, reads, &MBFI, mi); // Give extra weight to what looks like a loop induction variable update. if (writes && isExiting && LIS.isLiveOutOfMBB(li, mbb)) diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp index e1c3217a775..778ba4a5b95 100644 --- a/lib/CodeGen/LiveIntervalAnalysis.cpp +++ b/lib/CodeGen/LiveIntervalAnalysis.cpp @@ -22,6 +22,7 @@ #include "llvm/ADT/STLExtras.h" #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/CodeGen/LiveVariables.h" +#include "llvm/CodeGen/MachineBlockFrequencyInfo.h" #include "llvm/CodeGen/MachineDominators.h" #include "llvm/CodeGen/MachineInstr.h" #include "llvm/CodeGen/MachineRegisterInfo.h" @@ -620,9 +621,12 @@ LiveIntervals::hasPHIKill(const LiveInterval &LI, const VNInfo *VNI) const { } float -LiveIntervals::getSpillWeight(bool isDef, bool isUse, BlockFrequency freq) { - const float Scale = 1.0f / BlockFrequency::getEntryFrequency(); - return (isDef + isUse) * (freq.getFrequency() * Scale); +LiveIntervals::getSpillWeight(bool isDef, bool isUse, + const MachineBlockFrequencyInfo *MBFI, + const MachineInstr *MI) { + BlockFrequency Freq = MBFI->getBlockFreq(MI->getParent()); + const float Scale = 1.0f / MBFI->getEntryFrequency(); + return (isDef + isUse) * (Freq.getFrequency() * Scale); } LiveRange::Segment diff --git a/lib/CodeGen/RegAllocPBQP.cpp b/lib/CodeGen/RegAllocPBQP.cpp index 88c8201fd4b..483f2e1ae86 100644 --- a/lib/CodeGen/RegAllocPBQP.cpp +++ b/lib/CodeGen/RegAllocPBQP.cpp @@ -348,8 +348,7 @@ PBQPRAProblem *PBQPBuilderWithCoalescing::build(MachineFunction *mf, // value plucked randomly out of the air. PBQP::PBQPNum cBenefit = - copyFactor * LiveIntervals::getSpillWeight(false, true, - mbfi->getBlockFreq(mbb)); + copyFactor * LiveIntervals::getSpillWeight(false, true, mbfi, mi); if (cp.isPhys()) { if (!mf->getRegInfo().isAllocatable(dst)) { diff --git a/lib/CodeGen/StackSlotColoring.cpp b/lib/CodeGen/StackSlotColoring.cpp index 9f44df8f430..77c7047cde5 100644 --- a/lib/CodeGen/StackSlotColoring.cpp +++ b/lib/CodeGen/StackSlotColoring.cpp @@ -142,7 +142,6 @@ void StackSlotColoring::ScanForSpillSlotRefs(MachineFunction &MF) { for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end(); MBBI != E; ++MBBI) { MachineBasicBlock *MBB = &*MBBI; - BlockFrequency Freq = MBFI->getBlockFreq(MBB); for (MachineBasicBlock::iterator MII = MBB->begin(), EE = MBB->end(); MII != EE; ++MII) { MachineInstr *MI = &*MII; @@ -157,7 +156,7 @@ void StackSlotColoring::ScanForSpillSlotRefs(MachineFunction &MF) { continue; LiveInterval &li = LS->getInterval(FI); if (!MI->isDebugValue()) - li.weight += LiveIntervals::getSpillWeight(false, true, Freq); + li.weight += LiveIntervals::getSpillWeight(false, true, MBFI, MI); } for (MachineInstr::mmo_iterator MMOI = MI->memoperands_begin(), EE = MI->memoperands_end(); MMOI != EE; ++MMOI) {