forked from OSchip/llvm-project
1230 lines
46 KiB
C++
1230 lines
46 KiB
C++
//===-- TargetInstrInfo.cpp - Target Instruction Information --------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements the TargetInstrInfo class.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/CodeGen/TargetInstrInfo.h"
|
|
#include "llvm/CodeGen/MachineFrameInfo.h"
|
|
#include "llvm/CodeGen/MachineInstrBuilder.h"
|
|
#include "llvm/CodeGen/MachineMemOperand.h"
|
|
#include "llvm/CodeGen/MachineRegisterInfo.h"
|
|
#include "llvm/CodeGen/PseudoSourceValue.h"
|
|
#include "llvm/CodeGen/ScoreboardHazardRecognizer.h"
|
|
#include "llvm/CodeGen/StackMaps.h"
|
|
#include "llvm/CodeGen/TargetFrameLowering.h"
|
|
#include "llvm/CodeGen/TargetLowering.h"
|
|
#include "llvm/CodeGen/TargetRegisterInfo.h"
|
|
#include "llvm/CodeGen/TargetSchedule.h"
|
|
#include "llvm/IR/DataLayout.h"
|
|
#include "llvm/MC/MCAsmInfo.h"
|
|
#include "llvm/MC/MCInstrItineraries.h"
|
|
#include "llvm/Support/CommandLine.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
#include "llvm/Target/TargetMachine.h"
|
|
#include <cctype>
|
|
|
|
using namespace llvm;
|
|
|
|
static cl::opt<bool> DisableHazardRecognizer(
|
|
"disable-sched-hazard", cl::Hidden, cl::init(false),
|
|
cl::desc("Disable hazard detection during preRA scheduling"));
|
|
|
|
TargetInstrInfo::~TargetInstrInfo() {
|
|
}
|
|
|
|
const TargetRegisterClass*
|
|
TargetInstrInfo::getRegClass(const MCInstrDesc &MCID, unsigned OpNum,
|
|
const TargetRegisterInfo *TRI,
|
|
const MachineFunction &MF) const {
|
|
if (OpNum >= MCID.getNumOperands())
|
|
return nullptr;
|
|
|
|
short RegClass = MCID.OpInfo[OpNum].RegClass;
|
|
if (MCID.OpInfo[OpNum].isLookupPtrRegClass())
|
|
return TRI->getPointerRegClass(MF, RegClass);
|
|
|
|
// Instructions like INSERT_SUBREG do not have fixed register classes.
|
|
if (RegClass < 0)
|
|
return nullptr;
|
|
|
|
// Otherwise just look it up normally.
|
|
return TRI->getRegClass(RegClass);
|
|
}
|
|
|
|
/// insertNoop - Insert a noop into the instruction stream at the specified
|
|
/// point.
|
|
void TargetInstrInfo::insertNoop(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator MI) const {
|
|
llvm_unreachable("Target didn't implement insertNoop!");
|
|
}
|
|
|
|
static bool isAsmComment(const char *Str, const MCAsmInfo &MAI) {
|
|
return strncmp(Str, MAI.getCommentString().data(),
|
|
MAI.getCommentString().size()) == 0;
|
|
}
|
|
|
|
/// Measure the specified inline asm to determine an approximation of its
|
|
/// length.
|
|
/// Comments (which run till the next SeparatorString or newline) do not
|
|
/// count as an instruction.
|
|
/// Any other non-whitespace text is considered an instruction, with
|
|
/// multiple instructions separated by SeparatorString or newlines.
|
|
/// Variable-length instructions are not handled here; this function
|
|
/// may be overloaded in the target code to do that.
|
|
/// We implement a special case of the .space directive which takes only a
|
|
/// single integer argument in base 10 that is the size in bytes. This is a
|
|
/// restricted form of the GAS directive in that we only interpret
|
|
/// simple--i.e. not a logical or arithmetic expression--size values without
|
|
/// the optional fill value. This is primarily used for creating arbitrary
|
|
/// sized inline asm blocks for testing purposes.
|
|
unsigned TargetInstrInfo::getInlineAsmLength(
|
|
const char *Str,
|
|
const MCAsmInfo &MAI, const TargetSubtargetInfo *STI) const {
|
|
// Count the number of instructions in the asm.
|
|
bool AtInsnStart = true;
|
|
unsigned Length = 0;
|
|
const unsigned MaxInstLength = MAI.getMaxInstLength(STI);
|
|
for (; *Str; ++Str) {
|
|
if (*Str == '\n' || strncmp(Str, MAI.getSeparatorString(),
|
|
strlen(MAI.getSeparatorString())) == 0) {
|
|
AtInsnStart = true;
|
|
} else if (isAsmComment(Str, MAI)) {
|
|
// Stop counting as an instruction after a comment until the next
|
|
// separator.
|
|
AtInsnStart = false;
|
|
}
|
|
|
|
if (AtInsnStart && !std::isspace(static_cast<unsigned char>(*Str))) {
|
|
unsigned AddLength = MaxInstLength;
|
|
if (strncmp(Str, ".space", 6) == 0) {
|
|
char *EStr;
|
|
int SpaceSize;
|
|
SpaceSize = strtol(Str + 6, &EStr, 10);
|
|
SpaceSize = SpaceSize < 0 ? 0 : SpaceSize;
|
|
while (*EStr != '\n' && std::isspace(static_cast<unsigned char>(*EStr)))
|
|
++EStr;
|
|
if (*EStr == '\0' || *EStr == '\n' ||
|
|
isAsmComment(EStr, MAI)) // Successfully parsed .space argument
|
|
AddLength = SpaceSize;
|
|
}
|
|
Length += AddLength;
|
|
AtInsnStart = false;
|
|
}
|
|
}
|
|
|
|
return Length;
|
|
}
|
|
|
|
/// ReplaceTailWithBranchTo - Delete the instruction OldInst and everything
|
|
/// after it, replacing it with an unconditional branch to NewDest.
|
|
void
|
|
TargetInstrInfo::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
|
|
MachineBasicBlock *NewDest) const {
|
|
MachineBasicBlock *MBB = Tail->getParent();
|
|
|
|
// Remove all the old successors of MBB from the CFG.
|
|
while (!MBB->succ_empty())
|
|
MBB->removeSuccessor(MBB->succ_begin());
|
|
|
|
// Save off the debug loc before erasing the instruction.
|
|
DebugLoc DL = Tail->getDebugLoc();
|
|
|
|
// Update call site info and remove all the dead instructions
|
|
// from the end of MBB.
|
|
while (Tail != MBB->end()) {
|
|
auto MI = Tail++;
|
|
if (MI->isCall())
|
|
MBB->getParent()->updateCallSiteInfo(&*MI);
|
|
MBB->erase(MI);
|
|
}
|
|
|
|
// If MBB isn't immediately before MBB, insert a branch to it.
|
|
if (++MachineFunction::iterator(MBB) != MachineFunction::iterator(NewDest))
|
|
insertBranch(*MBB, NewDest, nullptr, SmallVector<MachineOperand, 0>(), DL);
|
|
MBB->addSuccessor(NewDest);
|
|
}
|
|
|
|
MachineInstr *TargetInstrInfo::commuteInstructionImpl(MachineInstr &MI,
|
|
bool NewMI, unsigned Idx1,
|
|
unsigned Idx2) const {
|
|
const MCInstrDesc &MCID = MI.getDesc();
|
|
bool HasDef = MCID.getNumDefs();
|
|
if (HasDef && !MI.getOperand(0).isReg())
|
|
// No idea how to commute this instruction. Target should implement its own.
|
|
return nullptr;
|
|
|
|
unsigned CommutableOpIdx1 = Idx1; (void)CommutableOpIdx1;
|
|
unsigned CommutableOpIdx2 = Idx2; (void)CommutableOpIdx2;
|
|
assert(findCommutedOpIndices(MI, CommutableOpIdx1, CommutableOpIdx2) &&
|
|
CommutableOpIdx1 == Idx1 && CommutableOpIdx2 == Idx2 &&
|
|
"TargetInstrInfo::CommuteInstructionImpl(): not commutable operands.");
|
|
assert(MI.getOperand(Idx1).isReg() && MI.getOperand(Idx2).isReg() &&
|
|
"This only knows how to commute register operands so far");
|
|
|
|
Register Reg0 = HasDef ? MI.getOperand(0).getReg() : Register();
|
|
Register Reg1 = MI.getOperand(Idx1).getReg();
|
|
Register Reg2 = MI.getOperand(Idx2).getReg();
|
|
unsigned SubReg0 = HasDef ? MI.getOperand(0).getSubReg() : 0;
|
|
unsigned SubReg1 = MI.getOperand(Idx1).getSubReg();
|
|
unsigned SubReg2 = MI.getOperand(Idx2).getSubReg();
|
|
bool Reg1IsKill = MI.getOperand(Idx1).isKill();
|
|
bool Reg2IsKill = MI.getOperand(Idx2).isKill();
|
|
bool Reg1IsUndef = MI.getOperand(Idx1).isUndef();
|
|
bool Reg2IsUndef = MI.getOperand(Idx2).isUndef();
|
|
bool Reg1IsInternal = MI.getOperand(Idx1).isInternalRead();
|
|
bool Reg2IsInternal = MI.getOperand(Idx2).isInternalRead();
|
|
// Avoid calling isRenamable for virtual registers since we assert that
|
|
// renamable property is only queried/set for physical registers.
|
|
bool Reg1IsRenamable = TargetRegisterInfo::isPhysicalRegister(Reg1)
|
|
? MI.getOperand(Idx1).isRenamable()
|
|
: false;
|
|
bool Reg2IsRenamable = TargetRegisterInfo::isPhysicalRegister(Reg2)
|
|
? MI.getOperand(Idx2).isRenamable()
|
|
: false;
|
|
// If destination is tied to either of the commuted source register, then
|
|
// it must be updated.
|
|
if (HasDef && Reg0 == Reg1 &&
|
|
MI.getDesc().getOperandConstraint(Idx1, MCOI::TIED_TO) == 0) {
|
|
Reg2IsKill = false;
|
|
Reg0 = Reg2;
|
|
SubReg0 = SubReg2;
|
|
} else if (HasDef && Reg0 == Reg2 &&
|
|
MI.getDesc().getOperandConstraint(Idx2, MCOI::TIED_TO) == 0) {
|
|
Reg1IsKill = false;
|
|
Reg0 = Reg1;
|
|
SubReg0 = SubReg1;
|
|
}
|
|
|
|
MachineInstr *CommutedMI = nullptr;
|
|
if (NewMI) {
|
|
// Create a new instruction.
|
|
MachineFunction &MF = *MI.getMF();
|
|
CommutedMI = MF.CloneMachineInstr(&MI);
|
|
} else {
|
|
CommutedMI = &MI;
|
|
}
|
|
|
|
if (HasDef) {
|
|
CommutedMI->getOperand(0).setReg(Reg0);
|
|
CommutedMI->getOperand(0).setSubReg(SubReg0);
|
|
}
|
|
CommutedMI->getOperand(Idx2).setReg(Reg1);
|
|
CommutedMI->getOperand(Idx1).setReg(Reg2);
|
|
CommutedMI->getOperand(Idx2).setSubReg(SubReg1);
|
|
CommutedMI->getOperand(Idx1).setSubReg(SubReg2);
|
|
CommutedMI->getOperand(Idx2).setIsKill(Reg1IsKill);
|
|
CommutedMI->getOperand(Idx1).setIsKill(Reg2IsKill);
|
|
CommutedMI->getOperand(Idx2).setIsUndef(Reg1IsUndef);
|
|
CommutedMI->getOperand(Idx1).setIsUndef(Reg2IsUndef);
|
|
CommutedMI->getOperand(Idx2).setIsInternalRead(Reg1IsInternal);
|
|
CommutedMI->getOperand(Idx1).setIsInternalRead(Reg2IsInternal);
|
|
// Avoid calling setIsRenamable for virtual registers since we assert that
|
|
// renamable property is only queried/set for physical registers.
|
|
if (TargetRegisterInfo::isPhysicalRegister(Reg1))
|
|
CommutedMI->getOperand(Idx2).setIsRenamable(Reg1IsRenamable);
|
|
if (TargetRegisterInfo::isPhysicalRegister(Reg2))
|
|
CommutedMI->getOperand(Idx1).setIsRenamable(Reg2IsRenamable);
|
|
return CommutedMI;
|
|
}
|
|
|
|
MachineInstr *TargetInstrInfo::commuteInstruction(MachineInstr &MI, bool NewMI,
|
|
unsigned OpIdx1,
|
|
unsigned OpIdx2) const {
|
|
// If OpIdx1 or OpIdx2 is not specified, then this method is free to choose
|
|
// any commutable operand, which is done in findCommutedOpIndices() method
|
|
// called below.
|
|
if ((OpIdx1 == CommuteAnyOperandIndex || OpIdx2 == CommuteAnyOperandIndex) &&
|
|
!findCommutedOpIndices(MI, OpIdx1, OpIdx2)) {
|
|
assert(MI.isCommutable() &&
|
|
"Precondition violation: MI must be commutable.");
|
|
return nullptr;
|
|
}
|
|
return commuteInstructionImpl(MI, NewMI, OpIdx1, OpIdx2);
|
|
}
|
|
|
|
bool TargetInstrInfo::fixCommutedOpIndices(unsigned &ResultIdx1,
|
|
unsigned &ResultIdx2,
|
|
unsigned CommutableOpIdx1,
|
|
unsigned CommutableOpIdx2) {
|
|
if (ResultIdx1 == CommuteAnyOperandIndex &&
|
|
ResultIdx2 == CommuteAnyOperandIndex) {
|
|
ResultIdx1 = CommutableOpIdx1;
|
|
ResultIdx2 = CommutableOpIdx2;
|
|
} else if (ResultIdx1 == CommuteAnyOperandIndex) {
|
|
if (ResultIdx2 == CommutableOpIdx1)
|
|
ResultIdx1 = CommutableOpIdx2;
|
|
else if (ResultIdx2 == CommutableOpIdx2)
|
|
ResultIdx1 = CommutableOpIdx1;
|
|
else
|
|
return false;
|
|
} else if (ResultIdx2 == CommuteAnyOperandIndex) {
|
|
if (ResultIdx1 == CommutableOpIdx1)
|
|
ResultIdx2 = CommutableOpIdx2;
|
|
else if (ResultIdx1 == CommutableOpIdx2)
|
|
ResultIdx2 = CommutableOpIdx1;
|
|
else
|
|
return false;
|
|
} else
|
|
// Check that the result operand indices match the given commutable
|
|
// operand indices.
|
|
return (ResultIdx1 == CommutableOpIdx1 && ResultIdx2 == CommutableOpIdx2) ||
|
|
(ResultIdx1 == CommutableOpIdx2 && ResultIdx2 == CommutableOpIdx1);
|
|
|
|
return true;
|
|
}
|
|
|
|
bool TargetInstrInfo::findCommutedOpIndices(MachineInstr &MI,
|
|
unsigned &SrcOpIdx1,
|
|
unsigned &SrcOpIdx2) const {
|
|
assert(!MI.isBundle() &&
|
|
"TargetInstrInfo::findCommutedOpIndices() can't handle bundles");
|
|
|
|
const MCInstrDesc &MCID = MI.getDesc();
|
|
if (!MCID.isCommutable())
|
|
return false;
|
|
|
|
// This assumes v0 = op v1, v2 and commuting would swap v1 and v2. If this
|
|
// is not true, then the target must implement this.
|
|
unsigned CommutableOpIdx1 = MCID.getNumDefs();
|
|
unsigned CommutableOpIdx2 = CommutableOpIdx1 + 1;
|
|
if (!fixCommutedOpIndices(SrcOpIdx1, SrcOpIdx2,
|
|
CommutableOpIdx1, CommutableOpIdx2))
|
|
return false;
|
|
|
|
if (!MI.getOperand(SrcOpIdx1).isReg() || !MI.getOperand(SrcOpIdx2).isReg())
|
|
// No idea.
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
bool TargetInstrInfo::isUnpredicatedTerminator(const MachineInstr &MI) const {
|
|
if (!MI.isTerminator()) return false;
|
|
|
|
// Conditional branch is a special case.
|
|
if (MI.isBranch() && !MI.isBarrier())
|
|
return true;
|
|
if (!MI.isPredicable())
|
|
return true;
|
|
return !isPredicated(MI);
|
|
}
|
|
|
|
bool TargetInstrInfo::PredicateInstruction(
|
|
MachineInstr &MI, ArrayRef<MachineOperand> Pred) const {
|
|
bool MadeChange = false;
|
|
|
|
assert(!MI.isBundle() &&
|
|
"TargetInstrInfo::PredicateInstruction() can't handle bundles");
|
|
|
|
const MCInstrDesc &MCID = MI.getDesc();
|
|
if (!MI.isPredicable())
|
|
return false;
|
|
|
|
for (unsigned j = 0, i = 0, e = MI.getNumOperands(); i != e; ++i) {
|
|
if (MCID.OpInfo[i].isPredicate()) {
|
|
MachineOperand &MO = MI.getOperand(i);
|
|
if (MO.isReg()) {
|
|
MO.setReg(Pred[j].getReg());
|
|
MadeChange = true;
|
|
} else if (MO.isImm()) {
|
|
MO.setImm(Pred[j].getImm());
|
|
MadeChange = true;
|
|
} else if (MO.isMBB()) {
|
|
MO.setMBB(Pred[j].getMBB());
|
|
MadeChange = true;
|
|
}
|
|
++j;
|
|
}
|
|
}
|
|
return MadeChange;
|
|
}
|
|
|
|
bool TargetInstrInfo::hasLoadFromStackSlot(
|
|
const MachineInstr &MI,
|
|
SmallVectorImpl<const MachineMemOperand *> &Accesses) const {
|
|
size_t StartSize = Accesses.size();
|
|
for (MachineInstr::mmo_iterator o = MI.memoperands_begin(),
|
|
oe = MI.memoperands_end();
|
|
o != oe; ++o) {
|
|
if ((*o)->isLoad() &&
|
|
dyn_cast_or_null<FixedStackPseudoSourceValue>((*o)->getPseudoValue()))
|
|
Accesses.push_back(*o);
|
|
}
|
|
return Accesses.size() != StartSize;
|
|
}
|
|
|
|
bool TargetInstrInfo::hasStoreToStackSlot(
|
|
const MachineInstr &MI,
|
|
SmallVectorImpl<const MachineMemOperand *> &Accesses) const {
|
|
size_t StartSize = Accesses.size();
|
|
for (MachineInstr::mmo_iterator o = MI.memoperands_begin(),
|
|
oe = MI.memoperands_end();
|
|
o != oe; ++o) {
|
|
if ((*o)->isStore() &&
|
|
dyn_cast_or_null<FixedStackPseudoSourceValue>((*o)->getPseudoValue()))
|
|
Accesses.push_back(*o);
|
|
}
|
|
return Accesses.size() != StartSize;
|
|
}
|
|
|
|
bool TargetInstrInfo::getStackSlotRange(const TargetRegisterClass *RC,
|
|
unsigned SubIdx, unsigned &Size,
|
|
unsigned &Offset,
|
|
const MachineFunction &MF) const {
|
|
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
|
|
if (!SubIdx) {
|
|
Size = TRI->getSpillSize(*RC);
|
|
Offset = 0;
|
|
return true;
|
|
}
|
|
unsigned BitSize = TRI->getSubRegIdxSize(SubIdx);
|
|
// Convert bit size to byte size.
|
|
if (BitSize % 8)
|
|
return false;
|
|
|
|
int BitOffset = TRI->getSubRegIdxOffset(SubIdx);
|
|
if (BitOffset < 0 || BitOffset % 8)
|
|
return false;
|
|
|
|
Size = BitSize /= 8;
|
|
Offset = (unsigned)BitOffset / 8;
|
|
|
|
assert(TRI->getSpillSize(*RC) >= (Offset + Size) && "bad subregister range");
|
|
|
|
if (!MF.getDataLayout().isLittleEndian()) {
|
|
Offset = TRI->getSpillSize(*RC) - (Offset + Size);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
void TargetInstrInfo::reMaterialize(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator I,
|
|
unsigned DestReg, unsigned SubIdx,
|
|
const MachineInstr &Orig,
|
|
const TargetRegisterInfo &TRI) const {
|
|
MachineInstr *MI = MBB.getParent()->CloneMachineInstr(&Orig);
|
|
MI->substituteRegister(MI->getOperand(0).getReg(), DestReg, SubIdx, TRI);
|
|
MBB.insert(I, MI);
|
|
}
|
|
|
|
bool TargetInstrInfo::produceSameValue(const MachineInstr &MI0,
|
|
const MachineInstr &MI1,
|
|
const MachineRegisterInfo *MRI) const {
|
|
return MI0.isIdenticalTo(MI1, MachineInstr::IgnoreVRegDefs);
|
|
}
|
|
|
|
MachineInstr &TargetInstrInfo::duplicate(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator InsertBefore, const MachineInstr &Orig) const {
|
|
assert(!Orig.isNotDuplicable() && "Instruction cannot be duplicated");
|
|
MachineFunction &MF = *MBB.getParent();
|
|
return MF.CloneMachineInstrBundle(MBB, InsertBefore, Orig);
|
|
}
|
|
|
|
// If the COPY instruction in MI can be folded to a stack operation, return
|
|
// the register class to use.
|
|
static const TargetRegisterClass *canFoldCopy(const MachineInstr &MI,
|
|
unsigned FoldIdx) {
|
|
assert(MI.isCopy() && "MI must be a COPY instruction");
|
|
if (MI.getNumOperands() != 2)
|
|
return nullptr;
|
|
assert(FoldIdx<2 && "FoldIdx refers no nonexistent operand");
|
|
|
|
const MachineOperand &FoldOp = MI.getOperand(FoldIdx);
|
|
const MachineOperand &LiveOp = MI.getOperand(1 - FoldIdx);
|
|
|
|
if (FoldOp.getSubReg() || LiveOp.getSubReg())
|
|
return nullptr;
|
|
|
|
unsigned FoldReg = FoldOp.getReg();
|
|
unsigned LiveReg = LiveOp.getReg();
|
|
|
|
assert(TargetRegisterInfo::isVirtualRegister(FoldReg) &&
|
|
"Cannot fold physregs");
|
|
|
|
const MachineRegisterInfo &MRI = MI.getMF()->getRegInfo();
|
|
const TargetRegisterClass *RC = MRI.getRegClass(FoldReg);
|
|
|
|
if (TargetRegisterInfo::isPhysicalRegister(LiveOp.getReg()))
|
|
return RC->contains(LiveOp.getReg()) ? RC : nullptr;
|
|
|
|
if (RC->hasSubClassEq(MRI.getRegClass(LiveReg)))
|
|
return RC;
|
|
|
|
// FIXME: Allow folding when register classes are memory compatible.
|
|
return nullptr;
|
|
}
|
|
|
|
void TargetInstrInfo::getNoop(MCInst &NopInst) const {
|
|
llvm_unreachable("Not implemented");
|
|
}
|
|
|
|
static MachineInstr *foldPatchpoint(MachineFunction &MF, MachineInstr &MI,
|
|
ArrayRef<unsigned> Ops, int FrameIndex,
|
|
const TargetInstrInfo &TII) {
|
|
unsigned StartIdx = 0;
|
|
switch (MI.getOpcode()) {
|
|
case TargetOpcode::STACKMAP: {
|
|
// StackMapLiveValues are foldable
|
|
StartIdx = StackMapOpers(&MI).getVarIdx();
|
|
break;
|
|
}
|
|
case TargetOpcode::PATCHPOINT: {
|
|
// For PatchPoint, the call args are not foldable (even if reported in the
|
|
// stackmap e.g. via anyregcc).
|
|
StartIdx = PatchPointOpers(&MI).getVarIdx();
|
|
break;
|
|
}
|
|
case TargetOpcode::STATEPOINT: {
|
|
// For statepoints, fold deopt and gc arguments, but not call arguments.
|
|
StartIdx = StatepointOpers(&MI).getVarIdx();
|
|
break;
|
|
}
|
|
default:
|
|
llvm_unreachable("unexpected stackmap opcode");
|
|
}
|
|
|
|
// Return false if any operands requested for folding are not foldable (not
|
|
// part of the stackmap's live values).
|
|
for (unsigned Op : Ops) {
|
|
if (Op < StartIdx)
|
|
return nullptr;
|
|
}
|
|
|
|
MachineInstr *NewMI =
|
|
MF.CreateMachineInstr(TII.get(MI.getOpcode()), MI.getDebugLoc(), true);
|
|
MachineInstrBuilder MIB(MF, NewMI);
|
|
|
|
// No need to fold return, the meta data, and function arguments
|
|
for (unsigned i = 0; i < StartIdx; ++i)
|
|
MIB.add(MI.getOperand(i));
|
|
|
|
for (unsigned i = StartIdx; i < MI.getNumOperands(); ++i) {
|
|
MachineOperand &MO = MI.getOperand(i);
|
|
if (is_contained(Ops, i)) {
|
|
unsigned SpillSize;
|
|
unsigned SpillOffset;
|
|
// Compute the spill slot size and offset.
|
|
const TargetRegisterClass *RC =
|
|
MF.getRegInfo().getRegClass(MO.getReg());
|
|
bool Valid =
|
|
TII.getStackSlotRange(RC, MO.getSubReg(), SpillSize, SpillOffset, MF);
|
|
if (!Valid)
|
|
report_fatal_error("cannot spill patchpoint subregister operand");
|
|
MIB.addImm(StackMaps::IndirectMemRefOp);
|
|
MIB.addImm(SpillSize);
|
|
MIB.addFrameIndex(FrameIndex);
|
|
MIB.addImm(SpillOffset);
|
|
}
|
|
else
|
|
MIB.add(MO);
|
|
}
|
|
return NewMI;
|
|
}
|
|
|
|
MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineInstr &MI,
|
|
ArrayRef<unsigned> Ops, int FI,
|
|
LiveIntervals *LIS,
|
|
VirtRegMap *VRM) const {
|
|
auto Flags = MachineMemOperand::MONone;
|
|
for (unsigned OpIdx : Ops)
|
|
Flags |= MI.getOperand(OpIdx).isDef() ? MachineMemOperand::MOStore
|
|
: MachineMemOperand::MOLoad;
|
|
|
|
MachineBasicBlock *MBB = MI.getParent();
|
|
assert(MBB && "foldMemoryOperand needs an inserted instruction");
|
|
MachineFunction &MF = *MBB->getParent();
|
|
|
|
// If we're not folding a load into a subreg, the size of the load is the
|
|
// size of the spill slot. But if we are, we need to figure out what the
|
|
// actual load size is.
|
|
int64_t MemSize = 0;
|
|
const MachineFrameInfo &MFI = MF.getFrameInfo();
|
|
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
|
|
|
|
if (Flags & MachineMemOperand::MOStore) {
|
|
MemSize = MFI.getObjectSize(FI);
|
|
} else {
|
|
for (unsigned OpIdx : Ops) {
|
|
int64_t OpSize = MFI.getObjectSize(FI);
|
|
|
|
if (auto SubReg = MI.getOperand(OpIdx).getSubReg()) {
|
|
unsigned SubRegSize = TRI->getSubRegIdxSize(SubReg);
|
|
if (SubRegSize > 0 && !(SubRegSize % 8))
|
|
OpSize = SubRegSize / 8;
|
|
}
|
|
|
|
MemSize = std::max(MemSize, OpSize);
|
|
}
|
|
}
|
|
|
|
assert(MemSize && "Did not expect a zero-sized stack slot");
|
|
|
|
MachineInstr *NewMI = nullptr;
|
|
|
|
if (MI.getOpcode() == TargetOpcode::STACKMAP ||
|
|
MI.getOpcode() == TargetOpcode::PATCHPOINT ||
|
|
MI.getOpcode() == TargetOpcode::STATEPOINT) {
|
|
// Fold stackmap/patchpoint.
|
|
NewMI = foldPatchpoint(MF, MI, Ops, FI, *this);
|
|
if (NewMI)
|
|
MBB->insert(MI, NewMI);
|
|
} else {
|
|
// Ask the target to do the actual folding.
|
|
NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, FI, LIS, VRM);
|
|
}
|
|
|
|
if (NewMI) {
|
|
NewMI->setMemRefs(MF, MI.memoperands());
|
|
// Add a memory operand, foldMemoryOperandImpl doesn't do that.
|
|
assert((!(Flags & MachineMemOperand::MOStore) ||
|
|
NewMI->mayStore()) &&
|
|
"Folded a def to a non-store!");
|
|
assert((!(Flags & MachineMemOperand::MOLoad) ||
|
|
NewMI->mayLoad()) &&
|
|
"Folded a use to a non-load!");
|
|
assert(MFI.getObjectOffset(FI) != -1);
|
|
MachineMemOperand *MMO = MF.getMachineMemOperand(
|
|
MachinePointerInfo::getFixedStack(MF, FI), Flags, MemSize,
|
|
MFI.getObjectAlignment(FI));
|
|
NewMI->addMemOperand(MF, MMO);
|
|
|
|
return NewMI;
|
|
}
|
|
|
|
// Straight COPY may fold as load/store.
|
|
if (!MI.isCopy() || Ops.size() != 1)
|
|
return nullptr;
|
|
|
|
const TargetRegisterClass *RC = canFoldCopy(MI, Ops[0]);
|
|
if (!RC)
|
|
return nullptr;
|
|
|
|
const MachineOperand &MO = MI.getOperand(1 - Ops[0]);
|
|
MachineBasicBlock::iterator Pos = MI;
|
|
|
|
if (Flags == MachineMemOperand::MOStore)
|
|
storeRegToStackSlot(*MBB, Pos, MO.getReg(), MO.isKill(), FI, RC, TRI);
|
|
else
|
|
loadRegFromStackSlot(*MBB, Pos, MO.getReg(), FI, RC, TRI);
|
|
return &*--Pos;
|
|
}
|
|
|
|
MachineInstr *TargetInstrInfo::foldMemoryOperand(MachineInstr &MI,
|
|
ArrayRef<unsigned> Ops,
|
|
MachineInstr &LoadMI,
|
|
LiveIntervals *LIS) const {
|
|
assert(LoadMI.canFoldAsLoad() && "LoadMI isn't foldable!");
|
|
#ifndef NDEBUG
|
|
for (unsigned OpIdx : Ops)
|
|
assert(MI.getOperand(OpIdx).isUse() && "Folding load into def!");
|
|
#endif
|
|
|
|
MachineBasicBlock &MBB = *MI.getParent();
|
|
MachineFunction &MF = *MBB.getParent();
|
|
|
|
// Ask the target to do the actual folding.
|
|
MachineInstr *NewMI = nullptr;
|
|
int FrameIndex = 0;
|
|
|
|
if ((MI.getOpcode() == TargetOpcode::STACKMAP ||
|
|
MI.getOpcode() == TargetOpcode::PATCHPOINT ||
|
|
MI.getOpcode() == TargetOpcode::STATEPOINT) &&
|
|
isLoadFromStackSlot(LoadMI, FrameIndex)) {
|
|
// Fold stackmap/patchpoint.
|
|
NewMI = foldPatchpoint(MF, MI, Ops, FrameIndex, *this);
|
|
if (NewMI)
|
|
NewMI = &*MBB.insert(MI, NewMI);
|
|
} else {
|
|
// Ask the target to do the actual folding.
|
|
NewMI = foldMemoryOperandImpl(MF, MI, Ops, MI, LoadMI, LIS);
|
|
}
|
|
|
|
if (!NewMI)
|
|
return nullptr;
|
|
|
|
// Copy the memoperands from the load to the folded instruction.
|
|
if (MI.memoperands_empty()) {
|
|
NewMI->setMemRefs(MF, LoadMI.memoperands());
|
|
} else {
|
|
// Handle the rare case of folding multiple loads.
|
|
NewMI->setMemRefs(MF, MI.memoperands());
|
|
for (MachineInstr::mmo_iterator I = LoadMI.memoperands_begin(),
|
|
E = LoadMI.memoperands_end();
|
|
I != E; ++I) {
|
|
NewMI->addMemOperand(MF, *I);
|
|
}
|
|
}
|
|
return NewMI;
|
|
}
|
|
|
|
bool TargetInstrInfo::hasReassociableOperands(
|
|
const MachineInstr &Inst, const MachineBasicBlock *MBB) const {
|
|
const MachineOperand &Op1 = Inst.getOperand(1);
|
|
const MachineOperand &Op2 = Inst.getOperand(2);
|
|
const MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
|
|
|
|
// We need virtual register definitions for the operands that we will
|
|
// reassociate.
|
|
MachineInstr *MI1 = nullptr;
|
|
MachineInstr *MI2 = nullptr;
|
|
if (Op1.isReg() && TargetRegisterInfo::isVirtualRegister(Op1.getReg()))
|
|
MI1 = MRI.getUniqueVRegDef(Op1.getReg());
|
|
if (Op2.isReg() && TargetRegisterInfo::isVirtualRegister(Op2.getReg()))
|
|
MI2 = MRI.getUniqueVRegDef(Op2.getReg());
|
|
|
|
// And they need to be in the trace (otherwise, they won't have a depth).
|
|
return MI1 && MI2 && MI1->getParent() == MBB && MI2->getParent() == MBB;
|
|
}
|
|
|
|
bool TargetInstrInfo::hasReassociableSibling(const MachineInstr &Inst,
|
|
bool &Commuted) const {
|
|
const MachineBasicBlock *MBB = Inst.getParent();
|
|
const MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
|
|
MachineInstr *MI1 = MRI.getUniqueVRegDef(Inst.getOperand(1).getReg());
|
|
MachineInstr *MI2 = MRI.getUniqueVRegDef(Inst.getOperand(2).getReg());
|
|
unsigned AssocOpcode = Inst.getOpcode();
|
|
|
|
// If only one operand has the same opcode and it's the second source operand,
|
|
// the operands must be commuted.
|
|
Commuted = MI1->getOpcode() != AssocOpcode && MI2->getOpcode() == AssocOpcode;
|
|
if (Commuted)
|
|
std::swap(MI1, MI2);
|
|
|
|
// 1. The previous instruction must be the same type as Inst.
|
|
// 2. The previous instruction must have virtual register definitions for its
|
|
// operands in the same basic block as Inst.
|
|
// 3. The previous instruction's result must only be used by Inst.
|
|
return MI1->getOpcode() == AssocOpcode &&
|
|
hasReassociableOperands(*MI1, MBB) &&
|
|
MRI.hasOneNonDBGUse(MI1->getOperand(0).getReg());
|
|
}
|
|
|
|
// 1. The operation must be associative and commutative.
|
|
// 2. The instruction must have virtual register definitions for its
|
|
// operands in the same basic block.
|
|
// 3. The instruction must have a reassociable sibling.
|
|
bool TargetInstrInfo::isReassociationCandidate(const MachineInstr &Inst,
|
|
bool &Commuted) const {
|
|
return isAssociativeAndCommutative(Inst) &&
|
|
hasReassociableOperands(Inst, Inst.getParent()) &&
|
|
hasReassociableSibling(Inst, Commuted);
|
|
}
|
|
|
|
// The concept of the reassociation pass is that these operations can benefit
|
|
// from this kind of transformation:
|
|
//
|
|
// A = ? op ?
|
|
// B = A op X (Prev)
|
|
// C = B op Y (Root)
|
|
// -->
|
|
// A = ? op ?
|
|
// B = X op Y
|
|
// C = A op B
|
|
//
|
|
// breaking the dependency between A and B, allowing them to be executed in
|
|
// parallel (or back-to-back in a pipeline) instead of depending on each other.
|
|
|
|
// FIXME: This has the potential to be expensive (compile time) while not
|
|
// improving the code at all. Some ways to limit the overhead:
|
|
// 1. Track successful transforms; bail out if hit rate gets too low.
|
|
// 2. Only enable at -O3 or some other non-default optimization level.
|
|
// 3. Pre-screen pattern candidates here: if an operand of the previous
|
|
// instruction is known to not increase the critical path, then don't match
|
|
// that pattern.
|
|
bool TargetInstrInfo::getMachineCombinerPatterns(
|
|
MachineInstr &Root,
|
|
SmallVectorImpl<MachineCombinerPattern> &Patterns) const {
|
|
bool Commute;
|
|
if (isReassociationCandidate(Root, Commute)) {
|
|
// We found a sequence of instructions that may be suitable for a
|
|
// reassociation of operands to increase ILP. Specify each commutation
|
|
// possibility for the Prev instruction in the sequence and let the
|
|
// machine combiner decide if changing the operands is worthwhile.
|
|
if (Commute) {
|
|
Patterns.push_back(MachineCombinerPattern::REASSOC_AX_YB);
|
|
Patterns.push_back(MachineCombinerPattern::REASSOC_XA_YB);
|
|
} else {
|
|
Patterns.push_back(MachineCombinerPattern::REASSOC_AX_BY);
|
|
Patterns.push_back(MachineCombinerPattern::REASSOC_XA_BY);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/// Return true when a code sequence can improve loop throughput.
|
|
bool
|
|
TargetInstrInfo::isThroughputPattern(MachineCombinerPattern Pattern) const {
|
|
return false;
|
|
}
|
|
|
|
/// Attempt the reassociation transformation to reduce critical path length.
|
|
/// See the above comments before getMachineCombinerPatterns().
|
|
void TargetInstrInfo::reassociateOps(
|
|
MachineInstr &Root, MachineInstr &Prev,
|
|
MachineCombinerPattern Pattern,
|
|
SmallVectorImpl<MachineInstr *> &InsInstrs,
|
|
SmallVectorImpl<MachineInstr *> &DelInstrs,
|
|
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg) const {
|
|
MachineFunction *MF = Root.getMF();
|
|
MachineRegisterInfo &MRI = MF->getRegInfo();
|
|
const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
|
|
const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
|
|
const TargetRegisterClass *RC = Root.getRegClassConstraint(0, TII, TRI);
|
|
|
|
// This array encodes the operand index for each parameter because the
|
|
// operands may be commuted. Each row corresponds to a pattern value,
|
|
// and each column specifies the index of A, B, X, Y.
|
|
unsigned OpIdx[4][4] = {
|
|
{ 1, 1, 2, 2 },
|
|
{ 1, 2, 2, 1 },
|
|
{ 2, 1, 1, 2 },
|
|
{ 2, 2, 1, 1 }
|
|
};
|
|
|
|
int Row;
|
|
switch (Pattern) {
|
|
case MachineCombinerPattern::REASSOC_AX_BY: Row = 0; break;
|
|
case MachineCombinerPattern::REASSOC_AX_YB: Row = 1; break;
|
|
case MachineCombinerPattern::REASSOC_XA_BY: Row = 2; break;
|
|
case MachineCombinerPattern::REASSOC_XA_YB: Row = 3; break;
|
|
default: llvm_unreachable("unexpected MachineCombinerPattern");
|
|
}
|
|
|
|
MachineOperand &OpA = Prev.getOperand(OpIdx[Row][0]);
|
|
MachineOperand &OpB = Root.getOperand(OpIdx[Row][1]);
|
|
MachineOperand &OpX = Prev.getOperand(OpIdx[Row][2]);
|
|
MachineOperand &OpY = Root.getOperand(OpIdx[Row][3]);
|
|
MachineOperand &OpC = Root.getOperand(0);
|
|
|
|
unsigned RegA = OpA.getReg();
|
|
unsigned RegB = OpB.getReg();
|
|
unsigned RegX = OpX.getReg();
|
|
unsigned RegY = OpY.getReg();
|
|
unsigned RegC = OpC.getReg();
|
|
|
|
if (TargetRegisterInfo::isVirtualRegister(RegA))
|
|
MRI.constrainRegClass(RegA, RC);
|
|
if (TargetRegisterInfo::isVirtualRegister(RegB))
|
|
MRI.constrainRegClass(RegB, RC);
|
|
if (TargetRegisterInfo::isVirtualRegister(RegX))
|
|
MRI.constrainRegClass(RegX, RC);
|
|
if (TargetRegisterInfo::isVirtualRegister(RegY))
|
|
MRI.constrainRegClass(RegY, RC);
|
|
if (TargetRegisterInfo::isVirtualRegister(RegC))
|
|
MRI.constrainRegClass(RegC, RC);
|
|
|
|
// Create a new virtual register for the result of (X op Y) instead of
|
|
// recycling RegB because the MachineCombiner's computation of the critical
|
|
// path requires a new register definition rather than an existing one.
|
|
unsigned NewVR = MRI.createVirtualRegister(RC);
|
|
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
|
|
|
|
unsigned Opcode = Root.getOpcode();
|
|
bool KillA = OpA.isKill();
|
|
bool KillX = OpX.isKill();
|
|
bool KillY = OpY.isKill();
|
|
|
|
// Create new instructions for insertion.
|
|
MachineInstrBuilder MIB1 =
|
|
BuildMI(*MF, Prev.getDebugLoc(), TII->get(Opcode), NewVR)
|
|
.addReg(RegX, getKillRegState(KillX))
|
|
.addReg(RegY, getKillRegState(KillY));
|
|
MachineInstrBuilder MIB2 =
|
|
BuildMI(*MF, Root.getDebugLoc(), TII->get(Opcode), RegC)
|
|
.addReg(RegA, getKillRegState(KillA))
|
|
.addReg(NewVR, getKillRegState(true));
|
|
|
|
setSpecialOperandAttr(Root, Prev, *MIB1, *MIB2);
|
|
|
|
// Record new instructions for insertion and old instructions for deletion.
|
|
InsInstrs.push_back(MIB1);
|
|
InsInstrs.push_back(MIB2);
|
|
DelInstrs.push_back(&Prev);
|
|
DelInstrs.push_back(&Root);
|
|
}
|
|
|
|
void TargetInstrInfo::genAlternativeCodeSequence(
|
|
MachineInstr &Root, MachineCombinerPattern Pattern,
|
|
SmallVectorImpl<MachineInstr *> &InsInstrs,
|
|
SmallVectorImpl<MachineInstr *> &DelInstrs,
|
|
DenseMap<unsigned, unsigned> &InstIdxForVirtReg) const {
|
|
MachineRegisterInfo &MRI = Root.getMF()->getRegInfo();
|
|
|
|
// Select the previous instruction in the sequence based on the input pattern.
|
|
MachineInstr *Prev = nullptr;
|
|
switch (Pattern) {
|
|
case MachineCombinerPattern::REASSOC_AX_BY:
|
|
case MachineCombinerPattern::REASSOC_XA_BY:
|
|
Prev = MRI.getUniqueVRegDef(Root.getOperand(1).getReg());
|
|
break;
|
|
case MachineCombinerPattern::REASSOC_AX_YB:
|
|
case MachineCombinerPattern::REASSOC_XA_YB:
|
|
Prev = MRI.getUniqueVRegDef(Root.getOperand(2).getReg());
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
assert(Prev && "Unknown pattern for machine combiner");
|
|
|
|
reassociateOps(Root, *Prev, Pattern, InsInstrs, DelInstrs, InstIdxForVirtReg);
|
|
}
|
|
|
|
bool TargetInstrInfo::isReallyTriviallyReMaterializableGeneric(
|
|
const MachineInstr &MI, AliasAnalysis *AA) const {
|
|
const MachineFunction &MF = *MI.getMF();
|
|
const MachineRegisterInfo &MRI = MF.getRegInfo();
|
|
|
|
// Remat clients assume operand 0 is the defined register.
|
|
if (!MI.getNumOperands() || !MI.getOperand(0).isReg())
|
|
return false;
|
|
unsigned DefReg = MI.getOperand(0).getReg();
|
|
|
|
// A sub-register definition can only be rematerialized if the instruction
|
|
// doesn't read the other parts of the register. Otherwise it is really a
|
|
// read-modify-write operation on the full virtual register which cannot be
|
|
// moved safely.
|
|
if (TargetRegisterInfo::isVirtualRegister(DefReg) &&
|
|
MI.getOperand(0).getSubReg() && MI.readsVirtualRegister(DefReg))
|
|
return false;
|
|
|
|
// A load from a fixed stack slot can be rematerialized. This may be
|
|
// redundant with subsequent checks, but it's target-independent,
|
|
// simple, and a common case.
|
|
int FrameIdx = 0;
|
|
if (isLoadFromStackSlot(MI, FrameIdx) &&
|
|
MF.getFrameInfo().isImmutableObjectIndex(FrameIdx))
|
|
return true;
|
|
|
|
// Avoid instructions obviously unsafe for remat.
|
|
if (MI.isNotDuplicable() || MI.mayStore() || MI.mayRaiseFPException() ||
|
|
MI.hasUnmodeledSideEffects())
|
|
return false;
|
|
|
|
// Don't remat inline asm. We have no idea how expensive it is
|
|
// even if it's side effect free.
|
|
if (MI.isInlineAsm())
|
|
return false;
|
|
|
|
// Avoid instructions which load from potentially varying memory.
|
|
if (MI.mayLoad() && !MI.isDereferenceableInvariantLoad(AA))
|
|
return false;
|
|
|
|
// If any of the registers accessed are non-constant, conservatively assume
|
|
// the instruction is not rematerializable.
|
|
for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) {
|
|
const MachineOperand &MO = MI.getOperand(i);
|
|
if (!MO.isReg()) continue;
|
|
unsigned Reg = MO.getReg();
|
|
if (Reg == 0)
|
|
continue;
|
|
|
|
// Check for a well-behaved physical register.
|
|
if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
|
|
if (MO.isUse()) {
|
|
// If the physreg has no defs anywhere, it's just an ambient register
|
|
// and we can freely move its uses. Alternatively, if it's allocatable,
|
|
// it could get allocated to something with a def during allocation.
|
|
if (!MRI.isConstantPhysReg(Reg))
|
|
return false;
|
|
} else {
|
|
// A physreg def. We can't remat it.
|
|
return false;
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// Only allow one virtual-register def. There may be multiple defs of the
|
|
// same virtual register, though.
|
|
if (MO.isDef() && Reg != DefReg)
|
|
return false;
|
|
|
|
// Don't allow any virtual-register uses. Rematting an instruction with
|
|
// virtual register uses would length the live ranges of the uses, which
|
|
// is not necessarily a good idea, certainly not "trivial".
|
|
if (MO.isUse())
|
|
return false;
|
|
}
|
|
|
|
// Everything checked out.
|
|
return true;
|
|
}
|
|
|
|
int TargetInstrInfo::getSPAdjust(const MachineInstr &MI) const {
|
|
const MachineFunction *MF = MI.getMF();
|
|
const TargetFrameLowering *TFI = MF->getSubtarget().getFrameLowering();
|
|
bool StackGrowsDown =
|
|
TFI->getStackGrowthDirection() == TargetFrameLowering::StackGrowsDown;
|
|
|
|
unsigned FrameSetupOpcode = getCallFrameSetupOpcode();
|
|
unsigned FrameDestroyOpcode = getCallFrameDestroyOpcode();
|
|
|
|
if (!isFrameInstr(MI))
|
|
return 0;
|
|
|
|
int SPAdj = TFI->alignSPAdjust(getFrameSize(MI));
|
|
|
|
if ((!StackGrowsDown && MI.getOpcode() == FrameSetupOpcode) ||
|
|
(StackGrowsDown && MI.getOpcode() == FrameDestroyOpcode))
|
|
SPAdj = -SPAdj;
|
|
|
|
return SPAdj;
|
|
}
|
|
|
|
/// isSchedulingBoundary - Test if the given instruction should be
|
|
/// considered a scheduling boundary. This primarily includes labels
|
|
/// and terminators.
|
|
bool TargetInstrInfo::isSchedulingBoundary(const MachineInstr &MI,
|
|
const MachineBasicBlock *MBB,
|
|
const MachineFunction &MF) const {
|
|
// Terminators and labels can't be scheduled around.
|
|
if (MI.isTerminator() || MI.isPosition())
|
|
return true;
|
|
|
|
// Don't attempt to schedule around any instruction that defines
|
|
// a stack-oriented pointer, as it's unlikely to be profitable. This
|
|
// saves compile time, because it doesn't require every single
|
|
// stack slot reference to depend on the instruction that does the
|
|
// modification.
|
|
const TargetLowering &TLI = *MF.getSubtarget().getTargetLowering();
|
|
const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
|
|
return MI.modifiesRegister(TLI.getStackPointerRegisterToSaveRestore(), TRI);
|
|
}
|
|
|
|
// Provide a global flag for disabling the PreRA hazard recognizer that targets
|
|
// may choose to honor.
|
|
bool TargetInstrInfo::usePreRAHazardRecognizer() const {
|
|
return !DisableHazardRecognizer;
|
|
}
|
|
|
|
// Default implementation of CreateTargetRAHazardRecognizer.
|
|
ScheduleHazardRecognizer *TargetInstrInfo::
|
|
CreateTargetHazardRecognizer(const TargetSubtargetInfo *STI,
|
|
const ScheduleDAG *DAG) const {
|
|
// Dummy hazard recognizer allows all instructions to issue.
|
|
return new ScheduleHazardRecognizer();
|
|
}
|
|
|
|
// Default implementation of CreateTargetMIHazardRecognizer.
|
|
ScheduleHazardRecognizer *TargetInstrInfo::
|
|
CreateTargetMIHazardRecognizer(const InstrItineraryData *II,
|
|
const ScheduleDAG *DAG) const {
|
|
return (ScheduleHazardRecognizer *)
|
|
new ScoreboardHazardRecognizer(II, DAG, "machine-scheduler");
|
|
}
|
|
|
|
// Default implementation of CreateTargetPostRAHazardRecognizer.
|
|
ScheduleHazardRecognizer *TargetInstrInfo::
|
|
CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
|
|
const ScheduleDAG *DAG) const {
|
|
return (ScheduleHazardRecognizer *)
|
|
new ScoreboardHazardRecognizer(II, DAG, "post-RA-sched");
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// SelectionDAG latency interface.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
int
|
|
TargetInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
|
|
SDNode *DefNode, unsigned DefIdx,
|
|
SDNode *UseNode, unsigned UseIdx) const {
|
|
if (!ItinData || ItinData->isEmpty())
|
|
return -1;
|
|
|
|
if (!DefNode->isMachineOpcode())
|
|
return -1;
|
|
|
|
unsigned DefClass = get(DefNode->getMachineOpcode()).getSchedClass();
|
|
if (!UseNode->isMachineOpcode())
|
|
return ItinData->getOperandCycle(DefClass, DefIdx);
|
|
unsigned UseClass = get(UseNode->getMachineOpcode()).getSchedClass();
|
|
return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx);
|
|
}
|
|
|
|
int TargetInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
|
|
SDNode *N) const {
|
|
if (!ItinData || ItinData->isEmpty())
|
|
return 1;
|
|
|
|
if (!N->isMachineOpcode())
|
|
return 1;
|
|
|
|
return ItinData->getStageLatency(get(N->getMachineOpcode()).getSchedClass());
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// MachineInstr latency interface.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
unsigned TargetInstrInfo::getNumMicroOps(const InstrItineraryData *ItinData,
|
|
const MachineInstr &MI) const {
|
|
if (!ItinData || ItinData->isEmpty())
|
|
return 1;
|
|
|
|
unsigned Class = MI.getDesc().getSchedClass();
|
|
int UOps = ItinData->Itineraries[Class].NumMicroOps;
|
|
if (UOps >= 0)
|
|
return UOps;
|
|
|
|
// The # of u-ops is dynamically determined. The specific target should
|
|
// override this function to return the right number.
|
|
return 1;
|
|
}
|
|
|
|
/// Return the default expected latency for a def based on it's opcode.
|
|
unsigned TargetInstrInfo::defaultDefLatency(const MCSchedModel &SchedModel,
|
|
const MachineInstr &DefMI) const {
|
|
if (DefMI.isTransient())
|
|
return 0;
|
|
if (DefMI.mayLoad())
|
|
return SchedModel.LoadLatency;
|
|
if (isHighLatencyDef(DefMI.getOpcode()))
|
|
return SchedModel.HighLatency;
|
|
return 1;
|
|
}
|
|
|
|
unsigned TargetInstrInfo::getPredicationCost(const MachineInstr &) const {
|
|
return 0;
|
|
}
|
|
|
|
unsigned TargetInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
|
|
const MachineInstr &MI,
|
|
unsigned *PredCost) const {
|
|
// Default to one cycle for no itinerary. However, an "empty" itinerary may
|
|
// still have a MinLatency property, which getStageLatency checks.
|
|
if (!ItinData)
|
|
return MI.mayLoad() ? 2 : 1;
|
|
|
|
return ItinData->getStageLatency(MI.getDesc().getSchedClass());
|
|
}
|
|
|
|
bool TargetInstrInfo::hasLowDefLatency(const TargetSchedModel &SchedModel,
|
|
const MachineInstr &DefMI,
|
|
unsigned DefIdx) const {
|
|
const InstrItineraryData *ItinData = SchedModel.getInstrItineraries();
|
|
if (!ItinData || ItinData->isEmpty())
|
|
return false;
|
|
|
|
unsigned DefClass = DefMI.getDesc().getSchedClass();
|
|
int DefCycle = ItinData->getOperandCycle(DefClass, DefIdx);
|
|
return (DefCycle != -1 && DefCycle <= 1);
|
|
}
|
|
|
|
/// Both DefMI and UseMI must be valid. By default, call directly to the
|
|
/// itinerary. This may be overriden by the target.
|
|
int TargetInstrInfo::getOperandLatency(const InstrItineraryData *ItinData,
|
|
const MachineInstr &DefMI,
|
|
unsigned DefIdx,
|
|
const MachineInstr &UseMI,
|
|
unsigned UseIdx) const {
|
|
unsigned DefClass = DefMI.getDesc().getSchedClass();
|
|
unsigned UseClass = UseMI.getDesc().getSchedClass();
|
|
return ItinData->getOperandLatency(DefClass, DefIdx, UseClass, UseIdx);
|
|
}
|
|
|
|
/// If we can determine the operand latency from the def only, without itinerary
|
|
/// lookup, do so. Otherwise return -1.
|
|
int TargetInstrInfo::computeDefOperandLatency(
|
|
const InstrItineraryData *ItinData, const MachineInstr &DefMI) const {
|
|
|
|
// Let the target hook getInstrLatency handle missing itineraries.
|
|
if (!ItinData)
|
|
return getInstrLatency(ItinData, DefMI);
|
|
|
|
if(ItinData->isEmpty())
|
|
return defaultDefLatency(ItinData->SchedModel, DefMI);
|
|
|
|
// ...operand lookup required
|
|
return -1;
|
|
}
|
|
|
|
bool TargetInstrInfo::getRegSequenceInputs(
|
|
const MachineInstr &MI, unsigned DefIdx,
|
|
SmallVectorImpl<RegSubRegPairAndIdx> &InputRegs) const {
|
|
assert((MI.isRegSequence() ||
|
|
MI.isRegSequenceLike()) && "Instruction do not have the proper type");
|
|
|
|
if (!MI.isRegSequence())
|
|
return getRegSequenceLikeInputs(MI, DefIdx, InputRegs);
|
|
|
|
// We are looking at:
|
|
// Def = REG_SEQUENCE v0, sub0, v1, sub1, ...
|
|
assert(DefIdx == 0 && "REG_SEQUENCE only has one def");
|
|
for (unsigned OpIdx = 1, EndOpIdx = MI.getNumOperands(); OpIdx != EndOpIdx;
|
|
OpIdx += 2) {
|
|
const MachineOperand &MOReg = MI.getOperand(OpIdx);
|
|
if (MOReg.isUndef())
|
|
continue;
|
|
const MachineOperand &MOSubIdx = MI.getOperand(OpIdx + 1);
|
|
assert(MOSubIdx.isImm() &&
|
|
"One of the subindex of the reg_sequence is not an immediate");
|
|
// Record Reg:SubReg, SubIdx.
|
|
InputRegs.push_back(RegSubRegPairAndIdx(MOReg.getReg(), MOReg.getSubReg(),
|
|
(unsigned)MOSubIdx.getImm()));
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool TargetInstrInfo::getExtractSubregInputs(
|
|
const MachineInstr &MI, unsigned DefIdx,
|
|
RegSubRegPairAndIdx &InputReg) const {
|
|
assert((MI.isExtractSubreg() ||
|
|
MI.isExtractSubregLike()) && "Instruction do not have the proper type");
|
|
|
|
if (!MI.isExtractSubreg())
|
|
return getExtractSubregLikeInputs(MI, DefIdx, InputReg);
|
|
|
|
// We are looking at:
|
|
// Def = EXTRACT_SUBREG v0.sub1, sub0.
|
|
assert(DefIdx == 0 && "EXTRACT_SUBREG only has one def");
|
|
const MachineOperand &MOReg = MI.getOperand(1);
|
|
if (MOReg.isUndef())
|
|
return false;
|
|
const MachineOperand &MOSubIdx = MI.getOperand(2);
|
|
assert(MOSubIdx.isImm() &&
|
|
"The subindex of the extract_subreg is not an immediate");
|
|
|
|
InputReg.Reg = MOReg.getReg();
|
|
InputReg.SubReg = MOReg.getSubReg();
|
|
InputReg.SubIdx = (unsigned)MOSubIdx.getImm();
|
|
return true;
|
|
}
|
|
|
|
bool TargetInstrInfo::getInsertSubregInputs(
|
|
const MachineInstr &MI, unsigned DefIdx,
|
|
RegSubRegPair &BaseReg, RegSubRegPairAndIdx &InsertedReg) const {
|
|
assert((MI.isInsertSubreg() ||
|
|
MI.isInsertSubregLike()) && "Instruction do not have the proper type");
|
|
|
|
if (!MI.isInsertSubreg())
|
|
return getInsertSubregLikeInputs(MI, DefIdx, BaseReg, InsertedReg);
|
|
|
|
// We are looking at:
|
|
// Def = INSERT_SEQUENCE v0, v1, sub0.
|
|
assert(DefIdx == 0 && "INSERT_SUBREG only has one def");
|
|
const MachineOperand &MOBaseReg = MI.getOperand(1);
|
|
const MachineOperand &MOInsertedReg = MI.getOperand(2);
|
|
if (MOInsertedReg.isUndef())
|
|
return false;
|
|
const MachineOperand &MOSubIdx = MI.getOperand(3);
|
|
assert(MOSubIdx.isImm() &&
|
|
"One of the subindex of the reg_sequence is not an immediate");
|
|
BaseReg.Reg = MOBaseReg.getReg();
|
|
BaseReg.SubReg = MOBaseReg.getSubReg();
|
|
|
|
InsertedReg.Reg = MOInsertedReg.getReg();
|
|
InsertedReg.SubReg = MOInsertedReg.getSubReg();
|
|
InsertedReg.SubIdx = (unsigned)MOSubIdx.getImm();
|
|
return true;
|
|
}
|