void MIPrinter::print(const MachineMemOperand &Op) {
OS << '(';
// TODO: Print operand's target specific flags.
if (Op.isVolatile())
OS << "volatile ";
if (Op.isNonTemporal())
OS << "non-temporal ";
if (Op.isInvariant())
OS << "invariant ";
if (Op.isLoad())
OS << "load ";
else {
assert(Op.isStore() && "Non load machine operand must be a store");
OS << "store ";
}
OS << Op.getSize() << (Op.isLoad() ? " from " : " into ");
if (const Value *Val = Op.getValue())
printIRValueReference(*Val);
// TODO: Print PseudoSourceValue.
printOffset(Op.getOffset());
if (Op.getBaseAlignment() != Op.getSize())
OS << ", align " << Op.getBaseAlignment();
// TODO: Print the metadata attributes.
OS << ')';
}
/// isLoadFromConstantMemory - Return true if the given instruction is a
/// load from constant memory. Machine LICM will hoist these even if they are
/// not re-materializable.
bool MachineLICM::isLoadFromConstantMemory(MachineInstr *MI) {
if (!MI->getDesc().mayLoad()) return false;
if (!MI->hasOneMemOperand()) return false;
MachineMemOperand *MMO = *MI->memoperands_begin();
if (MMO->isVolatile()) return false;
if (!MMO->getValue()) return false;
const PseudoSourceValue *PSV = dyn_cast<PseudoSourceValue>(MMO->getValue());
if (PSV) {
MachineFunction &MF = *MI->getParent()->getParent();
return PSV->isConstant(MF.getFrameInfo());
} else {
return AA->pointsToConstantMemory(MMO->getValue());
}
}
void MIPrinter::print(const MachineMemOperand &Op) {
OS << '(';
// TODO: Print operand's target specific flags.
if (Op.isVolatile())
OS << "volatile ";
if (Op.isNonTemporal())
OS << "non-temporal ";
if (Op.isInvariant())
OS << "invariant ";
if (Op.isLoad())
OS << "load ";
else {
assert(Op.isStore() && "Non load machine operand must be a store");
OS << "store ";
}
OS << Op.getSize() << (Op.isLoad() ? " from " : " into ");
if (const Value *Val = Op.getValue()) {
printIRValueReference(*Val);
} else {
const PseudoSourceValue *PVal = Op.getPseudoValue();
assert(PVal && "Expected a pseudo source value");
switch (PVal->kind()) {
case PseudoSourceValue::Stack:
OS << "stack";
break;
case PseudoSourceValue::GOT:
OS << "got";
break;
case PseudoSourceValue::JumpTable:
OS << "jump-table";
break;
case PseudoSourceValue::ConstantPool:
OS << "constant-pool";
break;
case PseudoSourceValue::FixedStack:
printStackObjectReference(
cast<FixedStackPseudoSourceValue>(PVal)->getFrameIndex());
break;
case PseudoSourceValue::GlobalValueCallEntry:
OS << "call-entry ";
cast<GlobalValuePseudoSourceValue>(PVal)->getValue()->printAsOperand(
OS, /*PrintType=*/false, MST);
break;
case PseudoSourceValue::ExternalSymbolCallEntry:
OS << "call-entry $";
printLLVMNameWithoutPrefix(
OS, cast<ExternalSymbolPseudoSourceValue>(PVal)->getSymbol());
break;
}
}
printOffset(Op.getOffset());
if (Op.getBaseAlignment() != Op.getSize())
OS << ", align " << Op.getBaseAlignment();
auto AAInfo = Op.getAAInfo();
if (AAInfo.TBAA) {
OS << ", !tbaa ";
AAInfo.TBAA->printAsOperand(OS, MST);
}
if (AAInfo.Scope) {
OS << ", !alias.scope ";
AAInfo.Scope->printAsOperand(OS, MST);
}
if (AAInfo.NoAlias) {
OS << ", !noalias ";
AAInfo.NoAlias->printAsOperand(OS, MST);
}
if (Op.getRanges()) {
OS << ", !range ";
Op.getRanges()->printAsOperand(OS, MST);
}
OS << ')';
}
void MIPrinter::print(const LLVMContext &Context, const TargetInstrInfo &TII,
const MachineMemOperand &Op) {
OS << '(';
if (Op.isVolatile())
OS << "volatile ";
if (Op.isNonTemporal())
OS << "non-temporal ";
if (Op.isDereferenceable())
OS << "dereferenceable ";
if (Op.isInvariant())
OS << "invariant ";
if (Op.getFlags() & MachineMemOperand::MOTargetFlag1)
OS << '"' << getTargetMMOFlagName(TII, MachineMemOperand::MOTargetFlag1)
<< "\" ";
if (Op.getFlags() & MachineMemOperand::MOTargetFlag2)
OS << '"' << getTargetMMOFlagName(TII, MachineMemOperand::MOTargetFlag2)
<< "\" ";
if (Op.getFlags() & MachineMemOperand::MOTargetFlag3)
OS << '"' << getTargetMMOFlagName(TII, MachineMemOperand::MOTargetFlag3)
<< "\" ";
assert((Op.isLoad() || Op.isStore()) && "machine memory operand must be a load or store (or both)");
if (Op.isLoad())
OS << "load ";
if (Op.isStore())
OS << "store ";
printSyncScope(Context, Op.getSyncScopeID());
if (Op.getOrdering() != AtomicOrdering::NotAtomic)
OS << toIRString(Op.getOrdering()) << ' ';
if (Op.getFailureOrdering() != AtomicOrdering::NotAtomic)
OS << toIRString(Op.getFailureOrdering()) << ' ';
OS << Op.getSize();
if (const Value *Val = Op.getValue()) {
OS << ((Op.isLoad() && Op.isStore()) ? " on "
: Op.isLoad() ? " from " : " into ");
printIRValueReference(*Val);
} else if (const PseudoSourceValue *PVal = Op.getPseudoValue()) {
OS << ((Op.isLoad() && Op.isStore()) ? " on "
: Op.isLoad() ? " from " : " into ");
assert(PVal && "Expected a pseudo source value");
switch (PVal->kind()) {
case PseudoSourceValue::Stack:
OS << "stack";
break;
case PseudoSourceValue::GOT:
OS << "got";
break;
case PseudoSourceValue::JumpTable:
OS << "jump-table";
break;
case PseudoSourceValue::ConstantPool:
OS << "constant-pool";
break;
case PseudoSourceValue::FixedStack:
printStackObjectReference(
cast<FixedStackPseudoSourceValue>(PVal)->getFrameIndex());
break;
case PseudoSourceValue::GlobalValueCallEntry:
OS << "call-entry ";
cast<GlobalValuePseudoSourceValue>(PVal)->getValue()->printAsOperand(
OS, /*PrintType=*/false, MST);
break;
case PseudoSourceValue::ExternalSymbolCallEntry:
OS << "call-entry $";
printLLVMNameWithoutPrefix(
OS, cast<ExternalSymbolPseudoSourceValue>(PVal)->getSymbol());
break;
case PseudoSourceValue::TargetCustom:
llvm_unreachable("TargetCustom pseudo source values are not supported");
break;
}
}
MachineOperand::printOperandOffset(OS, Op.getOffset());
if (Op.getBaseAlignment() != Op.getSize())
OS << ", align " << Op.getBaseAlignment();
auto AAInfo = Op.getAAInfo();
if (AAInfo.TBAA) {
OS << ", !tbaa ";
AAInfo.TBAA->printAsOperand(OS, MST);
}
if (AAInfo.Scope) {
OS << ", !alias.scope ";
AAInfo.Scope->printAsOperand(OS, MST);
}
if (AAInfo.NoAlias) {
OS << ", !noalias ";
AAInfo.NoAlias->printAsOperand(OS, MST);
}
if (Op.getRanges()) {
OS << ", !range ";
Op.getRanges()->printAsOperand(OS, MST);
}
OS << ')';
}
DeadMemOpElimination::instr_iterator
DeadMemOpElimination::handleMemOp(instr_iterator I, DefMapTy &Defs,
AliasSetTracker &AST) {
MachineInstr *MI = I;
MachineMemOperand *MO = *MI->memoperands_begin();
// AliasAnalysis cannot handle offset right now, so we pretend to write a
// a big enough size to the location pointed by the base pointer.
uint64_t Size = MO->getSize() + MO->getOffset();
AliasSet *ASet = &AST.getAliasSetForPointer(const_cast<Value*>(MO->getValue()),
Size, 0);
MachineInstr *&LastMI = Defs[ASet];
bool canHandleLastStore = LastMI && ASet->isMustAlias()
&& LastMI->getOpcode() != VTM::VOpInternalCall
// FIXME: We may need to remember the last
// definition for all predicates.
&& isPredIdentical(LastMI, MI);
if (canHandleLastStore) {
MachineMemOperand *LastMO = *LastMI->memoperands_begin();
// We can only handle last store if and only if their memory operand have
// the must-alias address and the same size.
canHandleLastStore = LastMO->getSize() == MO->getSize()
&& !LastMO->isVolatile()
&& MachineMemOperandAlias(MO, LastMO, AA, SE)
== AliasAnalysis::MustAlias;
}
// FIXME: These elimination is only valid if we are in single-thread mode!
if (VInstrInfo::mayStore(MI)) {
if (canHandleLastStore) {
// Dead store find, remove it.
LastMI->eraseFromParent();
++DeadStoreEliminated;
}
// Update the definition.
LastMI = MI;
return I;
}
// Now MI is a load.
if (!canHandleLastStore) return I;
// Loading the value that just be stored, the load is not necessary.
MachineOperand LoadedMO = MI->getOperand(0);
MachineOperand StoredMO = LastMI->getOperand(2);
// Simply replace the load by a copy.
DebugLoc dl = MI->getDebugLoc();
I = *BuildMI(*MI->getParent(), I, dl, VInstrInfo::getDesc(VTM::VOpMove))
.addOperand(LoadedMO).addOperand(StoredMO).
addOperand(*VInstrInfo::getPredOperand(MI)).
addOperand(*VInstrInfo::getTraceOperand(MI));
MI->eraseFromParent();
++DeadLoadEliminated;
return I;
}
