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@ -783,11 +783,14 @@ bool SimpleRegisterCoalescing::ReMaterializeTrivialDef(LiveInterval &SrcInt,
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/// being updated is not zero, make sure to set it to the correct physical
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/// subregister.
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void
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SimpleRegisterCoalescing::UpdateRegDefsUses(const CoalescerPair &CP) {
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bool DstIsPhys = CP.isPhys();
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unsigned SrcReg = CP.getSrcReg();
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unsigned DstReg = CP.getDstReg();
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unsigned SubIdx = CP.getSubIdx();
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SimpleRegisterCoalescing::UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg,
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unsigned SubIdx) {
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bool DstIsPhys = TargetRegisterInfo::isPhysicalRegister(DstReg);
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if (DstIsPhys && SubIdx) {
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// Figure out the real physical register we are updating with.
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DstReg = tri_->getSubReg(DstReg, SubIdx);
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SubIdx = 0;
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}
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// Collect all the instructions using SrcReg.
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SmallPtrSet<MachineInstr*, 32> Instrs;
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@ -1011,6 +1014,25 @@ SimpleRegisterCoalescing::ShortenDeadCopySrcLiveRange(LiveInterval &li,
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return removeIntervalIfEmpty(li, li_, tri_);
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}
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/// CanCoalesceWithImpDef - Returns true if the specified copy instruction
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/// from an implicit def to another register can be coalesced away.
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bool SimpleRegisterCoalescing::CanCoalesceWithImpDef(MachineInstr *CopyMI,
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LiveInterval &li,
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LiveInterval &ImpLi) const{
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if (!CopyMI->killsRegister(ImpLi.reg))
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return false;
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// Make sure this is the only use.
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for (MachineRegisterInfo::use_iterator UI = mri_->use_begin(ImpLi.reg),
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UE = mri_->use_end(); UI != UE;) {
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MachineInstr *UseMI = &*UI;
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++UI;
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if (CopyMI == UseMI || JoinedCopies.count(UseMI))
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continue;
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return false;
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}
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return true;
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}
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/// isWinToJoinCrossClass - Return true if it's profitable to coalesce
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/// two virtual registers from different register classes.
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@ -1197,6 +1219,17 @@ SimpleRegisterCoalescing::CanJoinInsertSubRegToPhysReg(unsigned DstReg,
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return true;
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}
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/// getRegAllocPreference - Return register allocation preference register.
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///
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static unsigned getRegAllocPreference(unsigned Reg, MachineFunction &MF,
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MachineRegisterInfo *MRI,
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const TargetRegisterInfo *TRI) {
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if (TargetRegisterInfo::isPhysicalRegister(Reg))
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return 0;
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std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(Reg);
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return TRI->ResolveRegAllocHint(Hint.first, Hint.second, MF);
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}
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/// JoinCopy - Attempt to join intervals corresponding to SrcReg/DstReg,
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/// which are the src/dst of the copy instruction CopyMI. This returns true
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/// if the copy was successfully coalesced away. If it is not currently
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@ -1211,131 +1244,393 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
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DEBUG(dbgs() << li_->getInstructionIndex(CopyMI) << '\t' << *CopyMI);
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unsigned SrcReg, DstReg, SrcSubIdx = 0, DstSubIdx = 0;
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bool isExtSubReg = CopyMI->isExtractSubreg();
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bool isInsSubReg = CopyMI->isInsertSubreg();
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bool isSubRegToReg = CopyMI->isSubregToReg();
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unsigned SubIdx = 0;
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if (isExtSubReg) {
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DstReg = CopyMI->getOperand(0).getReg();
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DstSubIdx = CopyMI->getOperand(0).getSubReg();
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SrcReg = CopyMI->getOperand(1).getReg();
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SrcSubIdx = CopyMI->getOperand(2).getImm();
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} else if (isInsSubReg || isSubRegToReg) {
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DstReg = CopyMI->getOperand(0).getReg();
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DstSubIdx = CopyMI->getOperand(3).getImm();
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SrcReg = CopyMI->getOperand(2).getReg();
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SrcSubIdx = CopyMI->getOperand(2).getSubReg();
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if (SrcSubIdx && SrcSubIdx != DstSubIdx) {
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// r1025 = INSERT_SUBREG r1025, r1024<2>, 2 Then r1024 has already been
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// coalesced to a larger register so the subreg indices cancel out.
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DEBUG(dbgs() << "\tSource of insert_subreg or subreg_to_reg is already "
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"coalesced to another register.\n");
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return false; // Not coalescable.
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}
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} else if (tii_->isMoveInstr(*CopyMI, SrcReg, DstReg, SrcSubIdx, DstSubIdx)) {
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if (SrcSubIdx && DstSubIdx && SrcSubIdx != DstSubIdx) {
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// e.g. %reg16404:1<def> = MOV8rr %reg16412:2<kill>
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Again = true;
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return false; // Not coalescable.
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}
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} else {
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llvm_unreachable("Unrecognized copy instruction!");
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}
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// If they are already joined we continue.
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if (SrcReg == DstReg) {
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DEBUG(dbgs() << "\tCopy already coalesced.\n");
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return false; // Not coalescable.
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}
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CoalescerPair CP(*tii_, *tri_);
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if (!CP.setRegisters(CopyMI)) {
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DEBUG(dbgs() << "\tNot coalescable.\n");
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return false;
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}
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// If they are already joined we continue.
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if (CP.getSrcReg() == CP.getDstReg()) {
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DEBUG(dbgs() << "\tCopy already coalesced.\n");
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bool SrcIsPhys = TargetRegisterInfo::isPhysicalRegister(SrcReg);
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bool DstIsPhys = TargetRegisterInfo::isPhysicalRegister(DstReg);
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// If they are both physical registers, we cannot join them.
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if (SrcIsPhys && DstIsPhys) {
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DEBUG(dbgs() << "\tCan not coalesce physregs.\n");
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return false; // Not coalescable.
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}
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DEBUG(dbgs() << "\tConsidering merging %reg" << CP.getSrcReg());
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// We only join virtual registers with allocatable physical registers.
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if (SrcIsPhys && !allocatableRegs_[SrcReg]) {
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DEBUG(dbgs() << "\tSrc reg is unallocatable physreg.\n");
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return false; // Not coalescable.
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}
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if (DstIsPhys && !allocatableRegs_[DstReg]) {
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DEBUG(dbgs() << "\tDst reg is unallocatable physreg.\n");
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return false; // Not coalescable.
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}
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// Enforce policies.
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if (CP.isPhys()) {
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DEBUG(dbgs() <<" with physreg %" << tri_->getName(CP.getDstReg()) << "\n");
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// Only coalesce to allocatable physreg.
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if (!allocatableRegs_[CP.getDstReg()]) {
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DEBUG(dbgs() << "\tRegister is an unallocatable physreg.\n");
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return false; // Not coalescable.
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// We cannot handle dual subreg indices and mismatched classes at the same
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// time.
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if (SrcSubIdx && DstSubIdx && differingRegisterClasses(SrcReg, DstReg)) {
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DEBUG(dbgs() << "\tCannot handle subreg indices and mismatched classes.\n");
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return false;
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}
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// Check that a physical source register is compatible with dst regclass
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if (SrcIsPhys) {
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unsigned SrcSubReg = SrcSubIdx ?
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tri_->getSubReg(SrcReg, SrcSubIdx) : SrcReg;
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const TargetRegisterClass *DstRC = mri_->getRegClass(DstReg);
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const TargetRegisterClass *DstSubRC = DstRC;
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if (DstSubIdx)
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DstSubRC = DstRC->getSubRegisterRegClass(DstSubIdx);
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assert(DstSubRC && "Illegal subregister index");
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if (!DstSubRC->contains(SrcSubReg)) {
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DEBUG(dbgs() << "\tIncompatible destination regclass: "
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<< "none of the super-registers of "
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<< tri_->getName(SrcSubReg) << " are in "
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<< DstSubRC->getName() << ".\n");
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return false; // Not coalescable.
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}
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} else {
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DEBUG({
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dbgs() << " with reg%" << CP.getDstReg();
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if (CP.getSubIdx())
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dbgs() << ":" << tri_->getSubRegIndexName(CP.getSubIdx());
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dbgs() << " to " << CP.getNewRC()->getName() << "\n";
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});
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}
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// Avoid constraining virtual register regclass too much.
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if (CP.isCrossClass()) {
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if (DisableCrossClassJoin) {
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DEBUG(dbgs() << "\tCross-class joins disabled.\n");
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return false;
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// Check that a physical dst register is compatible with source regclass
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if (DstIsPhys) {
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unsigned DstSubReg = DstSubIdx ?
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tri_->getSubReg(DstReg, DstSubIdx) : DstReg;
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const TargetRegisterClass *SrcRC = mri_->getRegClass(SrcReg);
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const TargetRegisterClass *SrcSubRC = SrcRC;
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if (SrcSubIdx)
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SrcSubRC = SrcRC->getSubRegisterRegClass(SrcSubIdx);
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assert(SrcSubRC && "Illegal subregister index");
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if (!SrcSubRC->contains(DstSubReg)) {
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DEBUG(dbgs() << "\tIncompatible source regclass: "
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<< "none of the super-registers of "
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<< tri_->getName(DstSubReg) << " are in "
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<< SrcSubRC->getName() << ".\n");
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(void)DstSubReg;
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return false; // Not coalescable.
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}
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}
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// Should be non-null only when coalescing to a sub-register class.
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bool CrossRC = false;
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const TargetRegisterClass *SrcRC= SrcIsPhys ? 0 : mri_->getRegClass(SrcReg);
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const TargetRegisterClass *DstRC= DstIsPhys ? 0 : mri_->getRegClass(DstReg);
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const TargetRegisterClass *NewRC = NULL;
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unsigned RealDstReg = 0;
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unsigned RealSrcReg = 0;
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if (isExtSubReg || isInsSubReg || isSubRegToReg) {
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SubIdx = CopyMI->getOperand(isExtSubReg ? 2 : 3).getImm();
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if (SrcIsPhys && isExtSubReg) {
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// r1024 = EXTRACT_SUBREG EAX, 0 then r1024 is really going to be
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// coalesced with AX.
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unsigned DstSubIdx = CopyMI->getOperand(0).getSubReg();
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if (DstSubIdx) {
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// r1024<2> = EXTRACT_SUBREG EAX, 2. Then r1024 has already been
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// coalesced to a larger register so the subreg indices cancel out.
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if (DstSubIdx != SubIdx) {
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DEBUG(dbgs() << "\t Sub-register indices mismatch.\n");
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return false; // Not coalescable.
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}
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} else
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SrcReg = tri_->getSubReg(SrcReg, SubIdx);
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SubIdx = 0;
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} else if (DstIsPhys && (isInsSubReg || isSubRegToReg)) {
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// EAX = INSERT_SUBREG EAX, r1024, 0
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unsigned SrcSubIdx = CopyMI->getOperand(2).getSubReg();
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if (SrcSubIdx) {
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// EAX = INSERT_SUBREG EAX, r1024<2>, 2 Then r1024 has already been
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// coalesced to a larger register so the subreg indices cancel out.
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if (SrcSubIdx != SubIdx) {
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DEBUG(dbgs() << "\t Sub-register indices mismatch.\n");
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return false; // Not coalescable.
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}
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} else
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DstReg = tri_->getSubReg(DstReg, SubIdx);
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SubIdx = 0;
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} else if ((DstIsPhys && isExtSubReg) ||
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(SrcIsPhys && (isInsSubReg || isSubRegToReg))) {
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if (!isSubRegToReg && CopyMI->getOperand(1).getSubReg()) {
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DEBUG(dbgs() << "\tSrc of extract_subreg already coalesced with reg"
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<< " of a super-class.\n");
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return false; // Not coalescable.
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}
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if (!isWinToJoinCrossClass(CP.getSrcReg(), CP.getDstReg(),
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mri_->getRegClass(CP.getSrcReg()),
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mri_->getRegClass(CP.getDstReg()),
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CP.getNewRC())) {
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// FIXME: The following checks are somewhat conservative. Perhaps a better
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// way to implement this is to treat this as coalescing a vr with the
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// super physical register.
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if (isExtSubReg) {
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if (!CanJoinExtractSubRegToPhysReg(DstReg, SrcReg, SubIdx, RealDstReg))
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return false; // Not coalescable
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} else {
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if (!CanJoinInsertSubRegToPhysReg(DstReg, SrcReg, SubIdx, RealSrcReg))
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return false; // Not coalescable
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}
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SubIdx = 0;
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} else {
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unsigned OldSubIdx = isExtSubReg ? CopyMI->getOperand(0).getSubReg()
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: CopyMI->getOperand(2).getSubReg();
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if (OldSubIdx) {
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if (OldSubIdx == SubIdx && !differingRegisterClasses(SrcReg, DstReg))
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// r1024<2> = EXTRACT_SUBREG r1025, 2. Then r1024 has already been
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// coalesced to a larger register so the subreg indices cancel out.
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// Also check if the other larger register is of the same register
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// class as the would be resulting register.
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SubIdx = 0;
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else {
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DEBUG(dbgs() << "\t Sub-register indices mismatch.\n");
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return false; // Not coalescable.
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}
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}
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if (SubIdx) {
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if (!DstIsPhys && !SrcIsPhys) {
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if (isInsSubReg || isSubRegToReg) {
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NewRC = tri_->getMatchingSuperRegClass(DstRC, SrcRC, SubIdx);
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} else // extract_subreg {
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NewRC = tri_->getMatchingSuperRegClass(SrcRC, DstRC, SubIdx);
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}
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if (!NewRC) {
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DEBUG(dbgs() << "\t Conflicting sub-register indices.\n");
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return false; // Not coalescable
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}
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if (!isWinToJoinCrossClass(SrcReg, DstReg, SrcRC, DstRC, NewRC)) {
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DEBUG(dbgs() << "\tAvoid coalescing to constrained register class: "
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<< SrcRC->getName() << "/"
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<< DstRC->getName() << " -> "
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<< NewRC->getName() << ".\n");
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Again = true; // May be possible to coalesce later.
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|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
} else if (differingRegisterClasses(SrcReg, DstReg)) {
|
|
|
|
|
if (DisableCrossClassJoin)
|
|
|
|
|
return false;
|
|
|
|
|
CrossRC = true;
|
|
|
|
|
|
|
|
|
|
// FIXME: What if the result of a EXTRACT_SUBREG is then coalesced
|
|
|
|
|
// with another? If it's the resulting destination register, then
|
|
|
|
|
// the subidx must be propagated to uses (but only those defined
|
|
|
|
|
// by the EXTRACT_SUBREG). If it's being coalesced into another
|
|
|
|
|
// register, it should be safe because register is assumed to have
|
|
|
|
|
// the register class of the super-register.
|
|
|
|
|
|
|
|
|
|
// Process moves where one of the registers have a sub-register index.
|
|
|
|
|
MachineOperand *DstMO = CopyMI->findRegisterDefOperand(DstReg);
|
|
|
|
|
MachineOperand *SrcMO = CopyMI->findRegisterUseOperand(SrcReg);
|
|
|
|
|
SubIdx = DstMO->getSubReg();
|
|
|
|
|
if (SubIdx) {
|
|
|
|
|
if (SrcMO->getSubReg())
|
|
|
|
|
// FIXME: can we handle this?
|
|
|
|
|
return false;
|
|
|
|
|
// This is not an insert_subreg but it looks like one.
|
|
|
|
|
// e.g. %reg1024:4 = MOV32rr %EAX
|
|
|
|
|
isInsSubReg = true;
|
|
|
|
|
if (SrcIsPhys) {
|
|
|
|
|
if (!CanJoinInsertSubRegToPhysReg(DstReg, SrcReg, SubIdx, RealSrcReg))
|
|
|
|
|
return false; // Not coalescable
|
|
|
|
|
SubIdx = 0;
|
|
|
|
|
}
|
|
|
|
|
} else {
|
|
|
|
|
SubIdx = SrcMO->getSubReg();
|
|
|
|
|
if (SubIdx) {
|
|
|
|
|
// This is not a extract_subreg but it looks like one.
|
|
|
|
|
// e.g. %cl = MOV16rr %reg1024:1
|
|
|
|
|
isExtSubReg = true;
|
|
|
|
|
if (DstIsPhys) {
|
|
|
|
|
if (!CanJoinExtractSubRegToPhysReg(DstReg, SrcReg, SubIdx,RealDstReg))
|
|
|
|
|
return false; // Not coalescable
|
|
|
|
|
SubIdx = 0;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Now determine the register class of the joined register.
|
|
|
|
|
if (!SrcIsPhys && !DstIsPhys) {
|
|
|
|
|
if (isExtSubReg) {
|
|
|
|
|
NewRC =
|
|
|
|
|
SubIdx ? tri_->getMatchingSuperRegClass(SrcRC, DstRC, SubIdx) : SrcRC;
|
|
|
|
|
} else if (isInsSubReg) {
|
|
|
|
|
NewRC =
|
|
|
|
|
SubIdx ? tri_->getMatchingSuperRegClass(DstRC, SrcRC, SubIdx) : DstRC;
|
|
|
|
|
} else {
|
|
|
|
|
NewRC = getCommonSubClass(SrcRC, DstRC);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (!NewRC) {
|
|
|
|
|
DEBUG(dbgs() << "\tDisjoint regclasses: "
|
|
|
|
|
<< SrcRC->getName() << ", "
|
|
|
|
|
<< DstRC->getName() << ".\n");
|
|
|
|
|
return false; // Not coalescable.
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// If we are joining two virtual registers and the resulting register
|
|
|
|
|
// class is more restrictive (fewer register, smaller size). Check if it's
|
|
|
|
|
// worth doing the merge.
|
|
|
|
|
if (!isWinToJoinCrossClass(SrcReg, DstReg, SrcRC, DstRC, NewRC)) {
|
|
|
|
|
DEBUG(dbgs() << "\tAvoid coalescing to constrained register class: "
|
|
|
|
|
<< CP.getNewRC()->getName() << ".\n");
|
|
|
|
|
<< SrcRC->getName() << "/"
|
|
|
|
|
<< DstRC->getName() << " -> "
|
|
|
|
|
<< NewRC->getName() << ".\n");
|
|
|
|
|
// Allow the coalescer to try again in case either side gets coalesced to
|
|
|
|
|
// a physical register that's compatible with the other side. e.g.
|
|
|
|
|
// r1024 = MOV32to32_ r1025
|
|
|
|
|
// But later r1024 is assigned EAX then r1025 may be coalesced with EAX.
|
|
|
|
|
Again = true; // May be possible to coalesce later.
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// When possible, let DstReg be the larger interval.
|
|
|
|
|
if (!CP.getSubIdx() && li_->getInterval(CP.getSrcReg()).ranges.size() >
|
|
|
|
|
li_->getInterval(CP.getDstReg()).ranges.size())
|
|
|
|
|
CP.flip();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// We need to be careful about coalescing a source physical register with a
|
|
|
|
|
// virtual register. Once the coalescing is done, it cannot be broken and
|
|
|
|
|
// these are not spillable! If the destination interval uses are far away,
|
|
|
|
|
// think twice about coalescing them!
|
|
|
|
|
// FIXME: Why are we skipping this test for partial copies?
|
|
|
|
|
// CodeGen/X86/phys_subreg_coalesce-3.ll needs it.
|
|
|
|
|
if (!CP.isPartial() && CP.isPhys()) {
|
|
|
|
|
LiveInterval &JoinVInt = li_->getInterval(CP.getSrcReg());
|
|
|
|
|
// Will it create illegal extract_subreg / insert_subreg?
|
|
|
|
|
if (SrcIsPhys && HasIncompatibleSubRegDefUse(CopyMI, DstReg, SrcReg))
|
|
|
|
|
return false;
|
|
|
|
|
if (DstIsPhys && HasIncompatibleSubRegDefUse(CopyMI, SrcReg, DstReg))
|
|
|
|
|
return false;
|
|
|
|
|
|
|
|
|
|
// Don't join with physregs that have a ridiculous number of live
|
|
|
|
|
// ranges. The data structure performance is really bad when that
|
|
|
|
|
// happens.
|
|
|
|
|
if (li_->hasInterval(CP.getDstReg()) &&
|
|
|
|
|
li_->getInterval(CP.getDstReg()).ranges.size() > 1000) {
|
|
|
|
|
mri_->setRegAllocationHint(CP.getSrcReg(), 0, CP.getDstReg());
|
|
|
|
|
++numAborts;
|
|
|
|
|
DEBUG(dbgs()
|
|
|
|
|
<< "\tPhysical register live interval too complicated, abort!\n");
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
LiveInterval &SrcInt = li_->getInterval(SrcReg);
|
|
|
|
|
LiveInterval &DstInt = li_->getInterval(DstReg);
|
|
|
|
|
assert(SrcInt.reg == SrcReg && DstInt.reg == DstReg &&
|
|
|
|
|
"Register mapping is horribly broken!");
|
|
|
|
|
|
|
|
|
|
const TargetRegisterClass *RC = mri_->getRegClass(CP.getSrcReg());
|
|
|
|
|
unsigned Threshold = allocatableRCRegs_[RC].count() * 2;
|
|
|
|
|
unsigned Length = li_->getApproximateInstructionCount(JoinVInt);
|
|
|
|
|
if (Length > Threshold &&
|
|
|
|
|
std::distance(mri_->use_nodbg_begin(CP.getSrcReg()),
|
|
|
|
|
mri_->use_nodbg_end()) * Threshold < Length) {
|
|
|
|
|
// Before giving up coalescing, if definition of source is defined by
|
|
|
|
|
// trivial computation, try rematerializing it.
|
|
|
|
|
if (!CP.isFlipped() &&
|
|
|
|
|
ReMaterializeTrivialDef(JoinVInt, CP.getDstReg(), 0, CopyMI))
|
|
|
|
|
return true;
|
|
|
|
|
DEBUG({
|
|
|
|
|
dbgs() << "\t\tInspecting ";
|
|
|
|
|
if (SrcRC) dbgs() << SrcRC->getName() << ": ";
|
|
|
|
|
SrcInt.print(dbgs(), tri_);
|
|
|
|
|
dbgs() << "\n\t\t and ";
|
|
|
|
|
if (DstRC) dbgs() << DstRC->getName() << ": ";
|
|
|
|
|
DstInt.print(dbgs(), tri_);
|
|
|
|
|
dbgs() << "\n";
|
|
|
|
|
});
|
|
|
|
|
|
|
|
|
|
mri_->setRegAllocationHint(CP.getSrcReg(), 0, CP.getDstReg());
|
|
|
|
|
++numAborts;
|
|
|
|
|
DEBUG(dbgs() << "\tMay tie down a physical register, abort!\n");
|
|
|
|
|
Again = true; // May be possible to coalesce later.
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// We may need the source interval after JoinIntervals has destroyed it.
|
|
|
|
|
// Save a copy of the virtual register live interval. We'll manually
|
|
|
|
|
// merge this into the "real" physical register live interval this is
|
|
|
|
|
// coalesced with.
|
|
|
|
|
OwningPtr<LiveInterval> SavedLI;
|
|
|
|
|
if (CP.getOrigDstReg() != CP.getDstReg())
|
|
|
|
|
SavedLI.reset(li_->dupInterval(&li_->getInterval(CP.getSrcReg())));
|
|
|
|
|
if (RealDstReg)
|
|
|
|
|
SavedLI.reset(li_->dupInterval(&SrcInt));
|
|
|
|
|
else if (RealSrcReg)
|
|
|
|
|
SavedLI.reset(li_->dupInterval(&DstInt));
|
|
|
|
|
|
|
|
|
|
if (!isExtSubReg && !isInsSubReg && !isSubRegToReg) {
|
|
|
|
|
// Check if it is necessary to propagate "isDead" property.
|
|
|
|
|
MachineOperand *mopd = CopyMI->findRegisterDefOperand(DstReg, false);
|
|
|
|
|
bool isDead = mopd->isDead();
|
|
|
|
|
|
|
|
|
|
// We need to be careful about coalescing a source physical register with a
|
|
|
|
|
// virtual register. Once the coalescing is done, it cannot be broken and
|
|
|
|
|
// these are not spillable! If the destination interval uses are far away,
|
|
|
|
|
// think twice about coalescing them!
|
|
|
|
|
if (!isDead && (SrcIsPhys || DstIsPhys)) {
|
|
|
|
|
// If the virtual register live interval is long but it has low use
|
|
|
|
|
// density, do not join them, instead mark the physical register as its
|
|
|
|
|
// allocation preference.
|
|
|
|
|
LiveInterval &JoinVInt = SrcIsPhys ? DstInt : SrcInt;
|
|
|
|
|
LiveInterval &JoinPInt = SrcIsPhys ? SrcInt : DstInt;
|
|
|
|
|
unsigned JoinVReg = SrcIsPhys ? DstReg : SrcReg;
|
|
|
|
|
unsigned JoinPReg = SrcIsPhys ? SrcReg : DstReg;
|
|
|
|
|
|
|
|
|
|
// Don't join with physregs that have a ridiculous number of live
|
|
|
|
|
// ranges. The data structure performance is really bad when that
|
|
|
|
|
// happens.
|
|
|
|
|
if (JoinPInt.ranges.size() > 1000) {
|
|
|
|
|
mri_->setRegAllocationHint(JoinVInt.reg, 0, JoinPReg);
|
|
|
|
|
++numAborts;
|
|
|
|
|
DEBUG(dbgs()
|
|
|
|
|
<< "\tPhysical register live interval too complicated, abort!\n");
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
const TargetRegisterClass *RC = mri_->getRegClass(JoinVReg);
|
|
|
|
|
unsigned Threshold = allocatableRCRegs_[RC].count() * 2;
|
|
|
|
|
unsigned Length = li_->getApproximateInstructionCount(JoinVInt);
|
|
|
|
|
if (Length > Threshold &&
|
|
|
|
|
std::distance(mri_->use_nodbg_begin(JoinVReg),
|
|
|
|
|
mri_->use_nodbg_end()) * Threshold < Length) {
|
|
|
|
|
// Before giving up coalescing, if definition of source is defined by
|
|
|
|
|
// trivial computation, try rematerializing it.
|
|
|
|
|
if (ReMaterializeTrivialDef(SrcInt, DstReg, DstSubIdx, CopyMI))
|
|
|
|
|
return true;
|
|
|
|
|
|
|
|
|
|
mri_->setRegAllocationHint(JoinVInt.reg, 0, JoinPReg);
|
|
|
|
|
++numAborts;
|
|
|
|
|
DEBUG(dbgs() << "\tMay tie down a physical register, abort!\n");
|
|
|
|
|
Again = true; // May be possible to coalesce later.
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Okay, attempt to join these two intervals. On failure, this returns false.
|
|
|
|
|
// Otherwise, if one of the intervals being joined is a physreg, this method
|
|
|
|
|
// always canonicalizes DstInt to be it. The output "SrcInt" will not have
|
|
|
|
|
// been modified, so we can use this information below to update aliases.
|
|
|
|
|
if (!JoinIntervals(CP)) {
|
|
|
|
|
bool Swapped = false;
|
|
|
|
|
// If SrcInt is implicitly defined, it's safe to coalesce.
|
|
|
|
|
if (SrcInt.empty()) {
|
|
|
|
|
if (!CanCoalesceWithImpDef(CopyMI, DstInt, SrcInt)) {
|
|
|
|
|
// Only coalesce an empty interval (defined by implicit_def) with
|
|
|
|
|
// another interval which has a valno defined by the CopyMI and the CopyMI
|
|
|
|
|
// is a kill of the implicit def.
|
|
|
|
|
DEBUG(dbgs() << "\tNot profitable!\n");
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
} else if (!JoinIntervals(DstInt, SrcInt, Swapped, CP)) {
|
|
|
|
|
// Coalescing failed.
|
|
|
|
|
|
|
|
|
|
// If definition of source is defined by trivial computation, try
|
|
|
|
|
// rematerializing it.
|
|
|
|
|
if (!CP.isFlipped() &&
|
|
|
|
|
ReMaterializeTrivialDef(li_->getInterval(CP.getSrcReg()),
|
|
|
|
|
CP.getDstReg(), 0, CopyMI))
|
|
|
|
|
if (!isExtSubReg && !isInsSubReg && !isSubRegToReg &&
|
|
|
|
|
ReMaterializeTrivialDef(SrcInt, DstReg, DstSubIdx, CopyMI))
|
|
|
|
|
return true;
|
|
|
|
|
|
|
|
|
|
// If we can eliminate the copy without merging the live ranges, do so now.
|
|
|
|
|
if (!CP.isPartial()) {
|
|
|
|
|
LiveInterval *UseInt = &li_->getInterval(CP.getSrcReg());
|
|
|
|
|
LiveInterval *DefInt = &li_->getInterval(CP.getDstReg());
|
|
|
|
|
if (CP.isFlipped())
|
|
|
|
|
std::swap(UseInt, DefInt);
|
|
|
|
|
if (AdjustCopiesBackFrom(*UseInt, *DefInt, CopyMI) ||
|
|
|
|
|
RemoveCopyByCommutingDef(*UseInt, *DefInt, CopyMI)) {
|
|
|
|
|
JoinedCopies.insert(CopyMI);
|
|
|
|
|
DEBUG(dbgs() << "\tTrivial!\n");
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
if (!isExtSubReg && !isInsSubReg && !isSubRegToReg &&
|
|
|
|
|
(AdjustCopiesBackFrom(SrcInt, DstInt, CopyMI) ||
|
|
|
|
|
RemoveCopyByCommutingDef(SrcInt, DstInt, CopyMI))) {
|
|
|
|
|
JoinedCopies.insert(CopyMI);
|
|
|
|
|
DEBUG(dbgs() << "\tTrivial!\n");
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Otherwise, we are unable to join the intervals.
|
|
|
|
@ -1344,15 +1639,25 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (CP.isPhys()) {
|
|
|
|
|
LiveInterval *ResSrcInt = &SrcInt;
|
|
|
|
|
LiveInterval *ResDstInt = &DstInt;
|
|
|
|
|
if (Swapped) {
|
|
|
|
|
std::swap(SrcReg, DstReg);
|
|
|
|
|
std::swap(ResSrcInt, ResDstInt);
|
|
|
|
|
}
|
|
|
|
|
assert(TargetRegisterInfo::isVirtualRegister(SrcReg) &&
|
|
|
|
|
"LiveInterval::join didn't work right!");
|
|
|
|
|
|
|
|
|
|
// If we're about to merge live ranges into a physical register live interval,
|
|
|
|
|
// we have to update any aliased register's live ranges to indicate that they
|
|
|
|
|
// have clobbered values for this range.
|
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(DstReg)) {
|
|
|
|
|
// If this is a extract_subreg where dst is a physical register, e.g.
|
|
|
|
|
// cl = EXTRACT_SUBREG reg1024, 1
|
|
|
|
|
// then create and update the actual physical register allocated to RHS.
|
|
|
|
|
unsigned LargerDstReg = CP.getDstReg();
|
|
|
|
|
if (CP.getOrigDstReg() != CP.getDstReg()) {
|
|
|
|
|
if (tri_->isSubRegister(CP.getOrigDstReg(), LargerDstReg))
|
|
|
|
|
LargerDstReg = CP.getOrigDstReg();
|
|
|
|
|
LiveInterval &RealInt = li_->getOrCreateInterval(CP.getDstReg());
|
|
|
|
|
if (RealDstReg || RealSrcReg) {
|
|
|
|
|
LiveInterval &RealInt =
|
|
|
|
|
li_->getOrCreateInterval(RealDstReg ? RealDstReg : RealSrcReg);
|
|
|
|
|
for (LiveInterval::const_vni_iterator I = SavedLI->vni_begin(),
|
|
|
|
|
E = SavedLI->vni_end(); I != E; ++I) {
|
|
|
|
|
const VNInfo *ValNo = *I;
|
|
|
|
@ -1364,45 +1669,56 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
|
|
|
|
|
RealInt.MergeValueInAsValue(*SavedLI, ValNo, NewValNo);
|
|
|
|
|
}
|
|
|
|
|
RealInt.weight += SavedLI->weight;
|
|
|
|
|
DstReg = RealDstReg ? RealDstReg : RealSrcReg;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Update the liveintervals of sub-registers.
|
|
|
|
|
LiveInterval &LargerInt = li_->getInterval(LargerDstReg);
|
|
|
|
|
for (const unsigned *AS = tri_->getSubRegisters(LargerDstReg); *AS; ++AS) {
|
|
|
|
|
LiveInterval &SRI = li_->getOrCreateInterval(*AS);
|
|
|
|
|
SRI.MergeInClobberRanges(*li_, LargerInt, li_->getVNInfoAllocator());
|
|
|
|
|
DEBUG({
|
|
|
|
|
dbgs() << "\t\tsubreg: "; SRI.print(dbgs(), tri_); dbgs() << "\n";
|
|
|
|
|
});
|
|
|
|
|
for (const unsigned *AS = tri_->getSubRegisters(DstReg); *AS; ++AS)
|
|
|
|
|
li_->getOrCreateInterval(*AS).MergeInClobberRanges(*li_, *ResSrcInt,
|
|
|
|
|
li_->getVNInfoAllocator());
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// If this is a EXTRACT_SUBREG, make sure the result of coalescing is the
|
|
|
|
|
// larger super-register.
|
|
|
|
|
if ((isExtSubReg || isInsSubReg || isSubRegToReg) &&
|
|
|
|
|
!SrcIsPhys && !DstIsPhys) {
|
|
|
|
|
if ((isExtSubReg && !Swapped) ||
|
|
|
|
|
((isInsSubReg || isSubRegToReg) && Swapped)) {
|
|
|
|
|
ResSrcInt->Copy(*ResDstInt, mri_, li_->getVNInfoAllocator());
|
|
|
|
|
std::swap(SrcReg, DstReg);
|
|
|
|
|
std::swap(ResSrcInt, ResDstInt);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Coalescing to a virtual register that is of a sub-register class of the
|
|
|
|
|
// other. Make sure the resulting register is set to the right register class.
|
|
|
|
|
if (CP.isCrossClass()) {
|
|
|
|
|
if (CrossRC)
|
|
|
|
|
++numCrossRCs;
|
|
|
|
|
mri_->setRegClass(CP.getDstReg(), CP.getNewRC());
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// This may happen even if it's cross-rc coalescing. e.g.
|
|
|
|
|
// %reg1026<def> = SUBREG_TO_REG 0, %reg1037<kill>, 4
|
|
|
|
|
// reg1026 -> GR64, reg1037 -> GR32_ABCD. The resulting register will have to
|
|
|
|
|
// be allocate a register from GR64_ABCD.
|
|
|
|
|
if (NewRC)
|
|
|
|
|
mri_->setRegClass(DstReg, NewRC);
|
|
|
|
|
|
|
|
|
|
// Remember to delete the copy instruction.
|
|
|
|
|
JoinedCopies.insert(CopyMI);
|
|
|
|
|
|
|
|
|
|
UpdateRegDefsUses(CP);
|
|
|
|
|
UpdateRegDefsUses(SrcReg, DstReg, SubIdx);
|
|
|
|
|
|
|
|
|
|
// If we have extended the live range of a physical register, make sure we
|
|
|
|
|
// update live-in lists as well.
|
|
|
|
|
if (CP.isPhys()) {
|
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(DstReg)) {
|
|
|
|
|
const LiveInterval &VRegInterval = li_->getInterval(SrcReg);
|
|
|
|
|
SmallVector<MachineBasicBlock*, 16> BlockSeq;
|
|
|
|
|
// JoinIntervals invalidates the VNInfos in SrcInt, but we only need the
|
|
|
|
|
// ranges for this, and they are preserved.
|
|
|
|
|
LiveInterval &SrcInt = li_->getInterval(CP.getSrcReg());
|
|
|
|
|
for (LiveInterval::const_iterator I = SrcInt.begin(), E = SrcInt.end();
|
|
|
|
|
I != E; ++I ) {
|
|
|
|
|
for (LiveInterval::const_iterator I = VRegInterval.begin(),
|
|
|
|
|
E = VRegInterval.end(); I != E; ++I ) {
|
|
|
|
|
li_->findLiveInMBBs(I->start, I->end, BlockSeq);
|
|
|
|
|
for (unsigned idx = 0, size = BlockSeq.size(); idx != size; ++idx) {
|
|
|
|
|
MachineBasicBlock &block = *BlockSeq[idx];
|
|
|
|
|
if (!block.isLiveIn(CP.getDstReg()))
|
|
|
|
|
block.addLiveIn(CP.getDstReg());
|
|
|
|
|
if (!block.isLiveIn(DstReg))
|
|
|
|
|
block.addLiveIn(DstReg);
|
|
|
|
|
}
|
|
|
|
|
BlockSeq.clear();
|
|
|
|
|
}
|
|
|
|
@ -1410,17 +1726,32 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
|
|
|
|
|
|
|
|
|
|
// SrcReg is guarateed to be the register whose live interval that is
|
|
|
|
|
// being merged.
|
|
|
|
|
li_->removeInterval(CP.getSrcReg());
|
|
|
|
|
li_->removeInterval(SrcReg);
|
|
|
|
|
|
|
|
|
|
// Update regalloc hint.
|
|
|
|
|
tri_->UpdateRegAllocHint(CP.getSrcReg(), CP.getDstReg(), *mf_);
|
|
|
|
|
tri_->UpdateRegAllocHint(SrcReg, DstReg, *mf_);
|
|
|
|
|
|
|
|
|
|
// Manually deleted the live interval copy.
|
|
|
|
|
if (SavedLI) {
|
|
|
|
|
SavedLI->clear();
|
|
|
|
|
SavedLI.reset();
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// If resulting interval has a preference that no longer fits because of subreg
|
|
|
|
|
// coalescing, just clear the preference.
|
|
|
|
|
unsigned Preference = getRegAllocPreference(ResDstInt->reg, *mf_, mri_, tri_);
|
|
|
|
|
if (Preference && (isExtSubReg || isInsSubReg || isSubRegToReg) &&
|
|
|
|
|
TargetRegisterInfo::isVirtualRegister(ResDstInt->reg)) {
|
|
|
|
|
const TargetRegisterClass *RC = mri_->getRegClass(ResDstInt->reg);
|
|
|
|
|
if (!RC->contains(Preference))
|
|
|
|
|
mri_->setRegAllocationHint(ResDstInt->reg, 0, 0);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
DEBUG({
|
|
|
|
|
LiveInterval &DstInt = li_->getInterval(CP.getDstReg());
|
|
|
|
|
dbgs() << "\tJoined. Result = ";
|
|
|
|
|
DstInt.print(dbgs(), tri_);
|
|
|
|
|
dbgs() << "\n";
|
|
|
|
|
});
|
|
|
|
|
dbgs() << "\t\tJoined. Result = ";
|
|
|
|
|
ResDstInt->print(dbgs(), tri_);
|
|
|
|
|
dbgs() << "\n";
|
|
|
|
|
});
|
|
|
|
|
|
|
|
|
|
++numJoins;
|
|
|
|
|
return true;
|
|
|
|
@ -1478,24 +1809,26 @@ static unsigned ComputeUltimateVN(VNInfo *VNI,
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
/// JoinIntervals - Attempt to join these two intervals. On failure, this
|
|
|
|
|
/// returns false.
|
|
|
|
|
bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
LiveInterval &RHS = li_->getInterval(CP.getSrcReg());
|
|
|
|
|
DEBUG({ dbgs() << "\t\tRHS = "; RHS.print(dbgs(), tri_); dbgs() << "\n"; });
|
|
|
|
|
|
|
|
|
|
// FIXME: Join into CP.getDstReg instead of CP.getOrigDstReg.
|
|
|
|
|
// When looking at
|
|
|
|
|
// %reg2000 = EXTRACT_SUBREG %EAX, sub_16bit
|
|
|
|
|
// we really want to join %reg2000 with %AX ( = CP.getDstReg). We are actually
|
|
|
|
|
// joining into %EAX ( = CP.getOrigDstReg) because it is guaranteed to have an
|
|
|
|
|
// existing live interval, and we are better equipped to handle interference.
|
|
|
|
|
// JoinCopy cleans up the mess by taking a copy of RHS before calling here,
|
|
|
|
|
// and merging that copy into CP.getDstReg after.
|
|
|
|
|
/// returns false. Otherwise, if one of the intervals being joined is a
|
|
|
|
|
/// physreg, this method always canonicalizes LHS to be it. The output
|
|
|
|
|
/// "RHS" will not have been modified, so we can use this information
|
|
|
|
|
/// below to update aliases.
|
|
|
|
|
bool
|
|
|
|
|
SimpleRegisterCoalescing::JoinIntervals(LiveInterval &LHS, LiveInterval &RHS,
|
|
|
|
|
bool &Swapped, CoalescerPair &CP) {
|
|
|
|
|
// Compute the final value assignment, assuming that the live ranges can be
|
|
|
|
|
// coalesced.
|
|
|
|
|
SmallVector<int, 16> LHSValNoAssignments;
|
|
|
|
|
SmallVector<int, 16> RHSValNoAssignments;
|
|
|
|
|
DenseMap<VNInfo*, VNInfo*> LHSValsDefinedFromRHS;
|
|
|
|
|
DenseMap<VNInfo*, VNInfo*> RHSValsDefinedFromLHS;
|
|
|
|
|
SmallVector<VNInfo*, 16> NewVNInfo;
|
|
|
|
|
|
|
|
|
|
// If a live interval is a physical register, conservatively check if any
|
|
|
|
|
// of its sub-registers is overlapping the live interval of the virtual
|
|
|
|
|
// register. If so, do not coalesce.
|
|
|
|
|
if (CP.isPhys() && *tri_->getSubRegisters(CP.getOrigDstReg())) {
|
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(LHS.reg) &&
|
|
|
|
|
*tri_->getSubRegisters(LHS.reg)) {
|
|
|
|
|
// If it's coalescing a virtual register to a physical register, estimate
|
|
|
|
|
// its live interval length. This is the *cost* of scanning an entire live
|
|
|
|
|
// interval. If the cost is low, we'll do an exhaustive check instead.
|
|
|
|
@ -1515,11 +1848,10 @@ bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
li_->intervalIsInOneMBB(RHS) &&
|
|
|
|
|
li_->getApproximateInstructionCount(RHS) <= 10) {
|
|
|
|
|
// Perform a more exhaustive check for some common cases.
|
|
|
|
|
if (li_->conflictsWithAliasRef(RHS, CP.getOrigDstReg(), JoinedCopies))
|
|
|
|
|
if (li_->conflictsWithSubPhysRegRef(RHS, LHS.reg, true, JoinedCopies))
|
|
|
|
|
return false;
|
|
|
|
|
} else {
|
|
|
|
|
for (const unsigned* SR = tri_->getAliasSet(CP.getOrigDstReg()); *SR;
|
|
|
|
|
++SR)
|
|
|
|
|
for (const unsigned* SR = tri_->getSubRegisters(LHS.reg); *SR; ++SR)
|
|
|
|
|
if (li_->hasInterval(*SR) && RHS.overlaps(li_->getInterval(*SR))) {
|
|
|
|
|
DEBUG({
|
|
|
|
|
dbgs() << "\tInterfere with sub-register ";
|
|
|
|
@ -1528,19 +1860,25 @@ bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
} else if (TargetRegisterInfo::isPhysicalRegister(RHS.reg) &&
|
|
|
|
|
*tri_->getSubRegisters(RHS.reg)) {
|
|
|
|
|
if (LHS.containsOneValue() &&
|
|
|
|
|
li_->getApproximateInstructionCount(LHS) <= 10) {
|
|
|
|
|
// Perform a more exhaustive check for some common cases.
|
|
|
|
|
if (li_->conflictsWithSubPhysRegRef(LHS, RHS.reg, false, JoinedCopies))
|
|
|
|
|
return false;
|
|
|
|
|
} else {
|
|
|
|
|
for (const unsigned* SR = tri_->getSubRegisters(RHS.reg); *SR; ++SR)
|
|
|
|
|
if (li_->hasInterval(*SR) && LHS.overlaps(li_->getInterval(*SR))) {
|
|
|
|
|
DEBUG({
|
|
|
|
|
dbgs() << "\tInterfere with sub-register ";
|
|
|
|
|
li_->getInterval(*SR).print(dbgs(), tri_);
|
|
|
|
|
});
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Compute the final value assignment, assuming that the live ranges can be
|
|
|
|
|
// coalesced.
|
|
|
|
|
SmallVector<int, 16> LHSValNoAssignments;
|
|
|
|
|
SmallVector<int, 16> RHSValNoAssignments;
|
|
|
|
|
DenseMap<VNInfo*, VNInfo*> LHSValsDefinedFromRHS;
|
|
|
|
|
DenseMap<VNInfo*, VNInfo*> RHSValsDefinedFromLHS;
|
|
|
|
|
SmallVector<VNInfo*, 16> NewVNInfo;
|
|
|
|
|
|
|
|
|
|
LiveInterval &LHS = li_->getInterval(CP.getOrigDstReg());
|
|
|
|
|
DEBUG({ dbgs() << "\t\tLHS = "; LHS.print(dbgs(), tri_); dbgs() << "\n"; });
|
|
|
|
|
|
|
|
|
|
// Loop over the value numbers of the LHS, seeing if any are defined from
|
|
|
|
|
// the RHS.
|
|
|
|
|
for (LiveInterval::vni_iterator i = LHS.vni_begin(), e = LHS.vni_end();
|
|
|
|
@ -1629,17 +1967,15 @@ bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
LiveInterval::const_iterator JE = RHS.end();
|
|
|
|
|
|
|
|
|
|
// Skip ahead until the first place of potential sharing.
|
|
|
|
|
if (I != IE && J != JE) {
|
|
|
|
|
if (I->start < J->start) {
|
|
|
|
|
I = std::upper_bound(I, IE, J->start);
|
|
|
|
|
if (I != LHS.begin()) --I;
|
|
|
|
|
} else if (J->start < I->start) {
|
|
|
|
|
J = std::upper_bound(J, JE, I->start);
|
|
|
|
|
if (J != RHS.begin()) --J;
|
|
|
|
|
}
|
|
|
|
|
if (I->start < J->start) {
|
|
|
|
|
I = std::upper_bound(I, IE, J->start);
|
|
|
|
|
if (I != LHS.begin()) --I;
|
|
|
|
|
} else if (J->start < I->start) {
|
|
|
|
|
J = std::upper_bound(J, JE, I->start);
|
|
|
|
|
if (J != RHS.begin()) --J;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
while (I != IE && J != JE) {
|
|
|
|
|
while (1) {
|
|
|
|
|
// Determine if these two live ranges overlap.
|
|
|
|
|
bool Overlaps;
|
|
|
|
|
if (I->start < J->start) {
|
|
|
|
@ -1661,10 +1997,13 @@ bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
return false;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (I->end < J->end)
|
|
|
|
|
if (I->end < J->end) {
|
|
|
|
|
++I;
|
|
|
|
|
else
|
|
|
|
|
if (I == IE) break;
|
|
|
|
|
} else {
|
|
|
|
|
++J;
|
|
|
|
|
if (J == JE) break;
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
// Update kill info. Some live ranges are extended due to copy coalescing.
|
|
|
|
@ -1689,15 +2028,19 @@ bool SimpleRegisterCoalescing::JoinIntervals(CoalescerPair &CP) {
|
|
|
|
|
LHS.addKills(NewVNInfo[RHSValID], VNI->kills);
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
if (LHSValNoAssignments.empty())
|
|
|
|
|
LHSValNoAssignments.push_back(-1);
|
|
|
|
|
if (RHSValNoAssignments.empty())
|
|
|
|
|
RHSValNoAssignments.push_back(-1);
|
|
|
|
|
|
|
|
|
|
// If we get here, we know that we can coalesce the live ranges. Ask the
|
|
|
|
|
// intervals to coalesce themselves now.
|
|
|
|
|
LHS.join(RHS, &LHSValNoAssignments[0], &RHSValNoAssignments[0], NewVNInfo,
|
|
|
|
|
mri_);
|
|
|
|
|
if ((RHS.ranges.size() > LHS.ranges.size() &&
|
|
|
|
|
TargetRegisterInfo::isVirtualRegister(LHS.reg)) ||
|
|
|
|
|
TargetRegisterInfo::isPhysicalRegister(RHS.reg)) {
|
|
|
|
|
RHS.join(LHS, &RHSValNoAssignments[0], &LHSValNoAssignments[0], NewVNInfo,
|
|
|
|
|
mri_);
|
|
|
|
|
Swapped = true;
|
|
|
|
|
} else {
|
|
|
|
|
LHS.join(RHS, &LHSValNoAssignments[0], &RHSValNoAssignments[0], NewVNInfo,
|
|
|
|
|
mri_);
|
|
|
|
|
Swapped = false;
|
|
|
|
|
}
|
|
|
|
|
return true;
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
@ -1977,8 +2320,8 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
|
|
|
|
|
if (!tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx)) {
|
|
|
|
|
assert((MI->isExtractSubreg() || MI->isInsertSubreg() ||
|
|
|
|
|
MI->isSubregToReg()) && "Unrecognized copy instruction");
|
|
|
|
|
SrcReg = MI->getOperand(MI->isSubregToReg() ? 2 : 1).getReg();
|
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(SrcReg))
|
|
|
|
|
DstReg = MI->getOperand(0).getReg();
|
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(DstReg))
|
|
|
|
|
// Do not delete extract_subreg, insert_subreg of physical
|
|
|
|
|
// registers unless the definition is dead. e.g.
|
|
|
|
|
// %DO<def> = INSERT_SUBREG %D0<undef>, %S0<kill>, 1
|
|
|
|
@ -1987,7 +2330,7 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
|
|
|
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DoDelete = false;
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}
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if (MI->allDefsAreDead()) {
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LiveInterval &li = li_->getInterval(SrcReg);
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LiveInterval &li = li_->getInterval(DstReg);
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if (!ShortenDeadCopySrcLiveRange(li, MI))
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ShortenDeadCopyLiveRange(li, MI);
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DoDelete = true;
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@ -2045,11 +2388,6 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
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if (MI->registerDefIsDead(DstReg)) {
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if (!ShortenDeadCopySrcLiveRange(RegInt, MI))
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ShortenDeadCopyLiveRange(RegInt, MI);
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} else {
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// If a value is killed here remove the marker.
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SlotIndex UseIdx = li_->getInstructionIndex(MI).getUseIndex();
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if (const LiveRange *LR = RegInt.getLiveRangeContaining(UseIdx))
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LR->valno->removeKill(UseIdx.getDefIndex());
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}
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}
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li_->RemoveMachineInstrFromMaps(MI);
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