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-rw-r--r--contrib/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp161
1 files changed, 57 insertions, 104 deletions
diff --git a/contrib/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp b/contrib/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
index e69d3e4..b29ea19 100644
--- a/contrib/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/contrib/llvm/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -59,13 +59,16 @@ DisableCrossClassJoin("disable-cross-class-join",
cl::desc("Avoid coalescing cross register class copies"),
cl::init(false), cl::Hidden);
-static RegisterPass<SimpleRegisterCoalescing>
-X("simple-register-coalescing", "Simple Register Coalescing");
+static cl::opt<bool>
+DisablePhysicalJoin("disable-physical-join",
+ cl::desc("Avoid coalescing physical register copies"),
+ cl::init(false), cl::Hidden);
-// Declare that we implement the RegisterCoalescer interface
-static RegisterAnalysisGroup<RegisterCoalescer, true/*The Default*/> V(X);
+INITIALIZE_AG_PASS(SimpleRegisterCoalescing, RegisterCoalescer,
+ "simple-register-coalescing", "Simple Register Coalescing",
+ false, false, true);
-const PassInfo *const llvm::SimpleRegisterCoalescingID = &X;
+char &llvm::SimpleRegisterCoalescingID = SimpleRegisterCoalescing::ID;
void SimpleRegisterCoalescing::getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
@@ -386,16 +389,12 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP,
if (HasOtherReachingDefs(IntA, IntB, AValNo, BValNo))
return false;
- bool BHasSubRegs = false;
- if (TargetRegisterInfo::isPhysicalRegister(IntB.reg))
- BHasSubRegs = *tri_->getSubRegisters(IntB.reg);
-
- // Abort if the subregisters of IntB.reg have values that are not simply the
+ // Abort if the aliases of IntB.reg have values that are not simply the
// clobbers from the superreg.
- if (BHasSubRegs)
- for (const unsigned *SR = tri_->getSubRegisters(IntB.reg); *SR; ++SR)
- if (li_->hasInterval(*SR) &&
- HasOtherReachingDefs(IntA, li_->getInterval(*SR), AValNo, 0))
+ if (TargetRegisterInfo::isPhysicalRegister(IntB.reg))
+ for (const unsigned *AS = tri_->getAliasSet(IntB.reg); *AS; ++AS)
+ if (li_->hasInterval(*AS) &&
+ HasOtherReachingDefs(IntA, li_->getInterval(*AS), AValNo, 0))
return false;
// If some of the uses of IntA.reg is already coalesced away, return false.
@@ -412,6 +411,8 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP,
return false;
}
+ DEBUG(dbgs() << "\tRemoveCopyByCommutingDef: " << *DefMI);
+
// At this point we have decided that it is legal to do this
// transformation. Start by commuting the instruction.
MachineBasicBlock *MBB = DefMI->getParent();
@@ -470,16 +471,12 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP,
if (Extended)
UseMO.setIsKill(false);
}
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
- if (UseMI->isCopy()) {
- if (UseMI->getOperand(0).getReg() != IntB.reg ||
- UseMI->getOperand(0).getSubReg())
- continue;
- } else if (tii_->isMoveInstr(*UseMI, SrcReg, DstReg, SrcSubIdx, DstSubIdx)){
- if (DstReg != IntB.reg || DstSubIdx)
- continue;
- } else
+ if (!UseMI->isCopy())
continue;
+ if (UseMI->getOperand(0).getReg() != IntB.reg ||
+ UseMI->getOperand(0).getSubReg())
+ continue;
+
// This copy will become a noop. If it's defining a new val#,
// remove that val# as well. However this live range is being
// extended to the end of the existing live range defined by the copy.
@@ -504,13 +501,13 @@ bool SimpleRegisterCoalescing::RemoveCopyByCommutingDef(const CoalescerPair &CP,
// Remove val#'s defined by copies that will be coalesced away.
for (unsigned i = 0, e = BDeadValNos.size(); i != e; ++i) {
VNInfo *DeadVNI = BDeadValNos[i];
- if (BHasSubRegs) {
- for (const unsigned *SR = tri_->getSubRegisters(IntB.reg); *SR; ++SR) {
- if (!li_->hasInterval(*SR))
+ if (TargetRegisterInfo::isPhysicalRegister(IntB.reg)) {
+ for (const unsigned *AS = tri_->getAliasSet(IntB.reg); *AS; ++AS) {
+ if (!li_->hasInterval(*AS))
continue;
- LiveInterval &SRLI = li_->getInterval(*SR);
- if (const LiveRange *SRLR = SRLI.getLiveRangeContaining(DeadVNI->def))
- SRLI.removeValNo(SRLR->valno);
+ LiveInterval &ASLI = li_->getInterval(*AS);
+ if (const LiveRange *ASLR = ASLI.getLiveRangeContaining(DeadVNI->def))
+ ASLI.removeValNo(ASLR->valno);
}
}
IntB.removeValNo(BDeadValNos[i]);
@@ -628,14 +625,6 @@ SimpleRegisterCoalescing::TrimLiveIntervalToLastUse(SlotIndex CopyIdx,
if (DefMO.getReg() == li.reg && !DefMO.getSubReg())
DefMO.setIsDead();
}
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
- if (tii_->isMoveInstr(*LastUseMI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
- DstReg == li.reg && DstSubIdx == 0) {
- // Last use is itself an identity code.
- int DeadIdx = LastUseMI->findRegisterDefOperandIdx(li.reg,
- false, false, tri_);
- LastUseMI->getOperand(DeadIdx).setIsDead();
- }
return true;
}
@@ -772,16 +761,6 @@ SimpleRegisterCoalescing::UpdateRegDefsUses(const CoalescerPair &CP) {
// A PhysReg copy that won't be coalesced can perhaps be rematerialized
// instead.
if (DstIsPhys) {
- unsigned CopySrcReg, CopyDstReg, CopySrcSubIdx, CopyDstSubIdx;
- if (tii_->isMoveInstr(*UseMI, CopySrcReg, CopyDstReg,
- CopySrcSubIdx, CopyDstSubIdx) &&
- CopySrcSubIdx == 0 && CopyDstSubIdx == 0 &&
- CopySrcReg != CopyDstReg && CopySrcReg == SrcReg &&
- CopyDstReg != DstReg && !JoinedCopies.count(UseMI) &&
- ReMaterializeTrivialDef(li_->getInterval(SrcReg), CopyDstReg, 0,
- UseMI))
- continue;
-
if (UseMI->isCopy() &&
!UseMI->getOperand(1).getSubReg() &&
!UseMI->getOperand(0).getSubReg() &&
@@ -834,28 +813,6 @@ SimpleRegisterCoalescing::UpdateRegDefsUses(const CoalescerPair &CP) {
dbgs() << li_->getInstructionIndex(UseMI) << "\t";
dbgs() << *UseMI;
});
-
-
- // After updating the operand, check if the machine instruction has
- // become a copy. If so, update its val# information.
- const TargetInstrDesc &TID = UseMI->getDesc();
- if (DstIsPhys || TID.getNumDefs() != 1 || TID.getNumOperands() <= 2)
- continue;
-
- unsigned CopySrcReg, CopyDstReg, CopySrcSubIdx, CopyDstSubIdx;
- if (tii_->isMoveInstr(*UseMI, CopySrcReg, CopyDstReg,
- CopySrcSubIdx, CopyDstSubIdx) &&
- CopySrcReg != CopyDstReg &&
- (TargetRegisterInfo::isVirtualRegister(CopyDstReg) ||
- allocatableRegs_[CopyDstReg])) {
- LiveInterval &LI = li_->getInterval(CopyDstReg);
- SlotIndex DefIdx =
- li_->getInstructionIndex(UseMI).getDefIndex();
- if (const LiveRange *DLR = LI.getLiveRangeContaining(DefIdx)) {
- if (DLR->valno->def == DefIdx)
- DLR->valno->setCopy(UseMI);
- }
- }
}
}
@@ -1082,13 +1039,18 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
return false; // Not coalescable.
}
+ if (DisablePhysicalJoin && CP.isPhys()) {
+ DEBUG(dbgs() << "\tPhysical joins disabled.\n");
+ return false;
+ }
+
DEBUG(dbgs() << "\tConsidering merging %reg" << CP.getSrcReg());
// Enforce policies.
if (CP.isPhys()) {
DEBUG(dbgs() <<" with physreg %" << tri_->getName(CP.getDstReg()) << "\n");
// Only coalesce to allocatable physreg.
- if (!allocatableRegs_[CP.getDstReg()]) {
+ if (!li_->isAllocatable(CP.getDstReg())) {
DEBUG(dbgs() << "\tRegister is an unallocatable physreg.\n");
return false; // Not coalescable.
}
@@ -1137,7 +1099,6 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
// 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");
@@ -1156,7 +1117,6 @@ bool SimpleRegisterCoalescing::JoinCopy(CopyRec &TheCopy, bool &Again) {
ReMaterializeTrivialDef(JoinVInt, CP.getDstReg(), 0, CopyMI))
return true;
- 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.
@@ -1543,21 +1503,19 @@ void SimpleRegisterCoalescing::CopyCoalesceInMBB(MachineBasicBlock *MBB,
MachineInstr *Inst = MII++;
// If this isn't a copy nor a extract_subreg, we can't join intervals.
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
- bool isInsUndef = false;
+ unsigned SrcReg, DstReg;
if (Inst->isCopy()) {
DstReg = Inst->getOperand(0).getReg();
SrcReg = Inst->getOperand(1).getReg();
} else if (Inst->isSubregToReg()) {
DstReg = Inst->getOperand(0).getReg();
SrcReg = Inst->getOperand(2).getReg();
- } else if (!tii_->isMoveInstr(*Inst, SrcReg, DstReg, SrcSubIdx, DstSubIdx))
+ } else
continue;
bool SrcIsPhys = TargetRegisterInfo::isPhysicalRegister(SrcReg);
bool DstIsPhys = TargetRegisterInfo::isPhysicalRegister(DstReg);
- if (isInsUndef ||
- (li_->hasInterval(SrcReg) && li_->getInterval(SrcReg).empty()))
+ if (li_->hasInterval(SrcReg) && li_->getInterval(SrcReg).empty())
ImpDefCopies.push_back(CopyRec(Inst, 0));
else if (SrcIsPhys || DstIsPhys)
PhysCopies.push_back(CopyRec(Inst, 0));
@@ -1679,11 +1637,6 @@ SimpleRegisterCoalescing::lastRegisterUse(SlotIndex Start,
MachineInstr *UseMI = Use.getParent();
if (UseMI->isIdentityCopy())
continue;
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
- if (tii_->isMoveInstr(*UseMI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
- SrcReg == DstReg && SrcSubIdx == DstSubIdx)
- // Ignore identity copies.
- continue;
SlotIndex Idx = li_->getInstructionIndex(UseMI);
// FIXME: Should this be Idx != UseIdx? SlotIndex() will return something
// that compares higher than any other interval.
@@ -1708,10 +1661,7 @@ SimpleRegisterCoalescing::lastRegisterUse(SlotIndex Start,
return NULL;
// Ignore identity copies.
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
- if (!MI->isIdentityCopy() &&
- !(tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx) &&
- SrcReg == DstReg && SrcSubIdx == DstSubIdx))
+ if (!MI->isIdentityCopy())
for (unsigned i = 0, NumOps = MI->getNumOperands(); i != NumOps; ++i) {
MachineOperand &Use = MI->getOperand(i);
if (Use.isReg() && Use.isUse() && Use.getReg() &&
@@ -1747,7 +1697,6 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
<< "********** Function: "
<< ((Value*)mf_->getFunction())->getName() << '\n');
- allocatableRegs_ = tri_->getAllocatableSet(fn);
for (TargetRegisterInfo::regclass_iterator I = tri_->regclass_begin(),
E = tri_->regclass_end(); I != E; ++I)
allocatableRCRegs_.insert(std::make_pair(*I,
@@ -1775,30 +1724,35 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
for (MachineBasicBlock::iterator mii = mbb->begin(), mie = mbb->end();
mii != mie; ) {
MachineInstr *MI = mii;
- unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
if (JoinedCopies.count(MI)) {
// Delete all coalesced copies.
bool DoDelete = true;
- if (!tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx)) {
- assert(MI->isCopyLike() && "Unrecognized copy instruction");
- SrcReg = MI->getOperand(MI->isSubregToReg() ? 2 : 1).getReg();
- if (TargetRegisterInfo::isPhysicalRegister(SrcReg))
- // 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
- // or else the scavenger may complain. LowerSubregs will
- // delete them later.
- DoDelete = false;
- }
+ assert(MI->isCopyLike() && "Unrecognized copy instruction");
+ unsigned SrcReg = MI->getOperand(MI->isSubregToReg() ? 2 : 1).getReg();
+ if (TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
+ MI->getNumOperands() > 2)
+ // 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
+ // or else the scavenger may complain. LowerSubregs will
+ // delete them later.
+ DoDelete = false;
+
if (MI->allDefsAreDead()) {
LiveInterval &li = li_->getInterval(SrcReg);
if (!ShortenDeadCopySrcLiveRange(li, MI))
ShortenDeadCopyLiveRange(li, MI);
DoDelete = true;
}
- if (!DoDelete)
+ if (!DoDelete) {
+ // We need the instruction to adjust liveness, so make it a KILL.
+ if (MI->isSubregToReg()) {
+ MI->RemoveOperand(3);
+ MI->RemoveOperand(1);
+ }
+ MI->setDesc(tii_->get(TargetOpcode::KILL));
mii = llvm::next(mii);
- else {
+ } else {
li_->RemoveMachineInstrFromMaps(MI);
mii = mbbi->erase(mii);
++numPeep;
@@ -1840,9 +1794,8 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) {
}
// If the move will be an identity move delete it
- bool isMove= tii_->isMoveInstr(*MI, SrcReg, DstReg, SrcSubIdx, DstSubIdx);
- if (MI->isIdentityCopy() ||
- (isMove && SrcReg == DstReg && SrcSubIdx == DstSubIdx)) {
+ if (MI->isIdentityCopy()) {
+ unsigned SrcReg = MI->getOperand(1).getReg();
if (li_->hasInterval(SrcReg)) {
LiveInterval &RegInt = li_->getInterval(SrcReg);
// If def of this move instruction is dead, remove its live range
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