mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-11-10 01:10:48 +00:00
e3cc84a43d
stick with a constant estimate of 90% (branch predictors are good!), but we might find that we want to provide more nuanced estimates in the future. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115364 91177308-0d34-0410-b5e6-96231b3b80d8
650 lines
21 KiB
C++
650 lines
21 KiB
C++
//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information ----*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file contains the Thumb-2 implementation of the TargetInstrInfo class.
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//
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//===----------------------------------------------------------------------===//
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#include "Thumb2InstrInfo.h"
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#include "ARM.h"
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#include "ARMConstantPoolValue.h"
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#include "ARMAddressingModes.h"
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#include "ARMGenInstrInfo.inc"
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#include "ARMMachineFunctionInfo.h"
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#include "Thumb2HazardRecognizer.h"
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#include "Thumb2InstrInfo.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineMemOperand.h"
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#include "llvm/CodeGen/PseudoSourceValue.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/Support/CommandLine.h"
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using namespace llvm;
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static cl::opt<bool>
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OldT2IfCvt("old-thumb2-ifcvt", cl::Hidden,
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cl::desc("Use old-style Thumb2 if-conversion heuristics"),
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cl::init(false));
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Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
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: ARMBaseInstrInfo(STI), RI(*this, STI) {
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}
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unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {
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// FIXME
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return 0;
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}
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bool Thumb2InstrInfo::isProfitableToIfCvt(MachineBasicBlock &MBB,
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unsigned NumInstrs,
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float Prediction,
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float Confidence) const {
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if (!OldT2IfCvt)
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return ARMBaseInstrInfo::isProfitableToIfCvt(MBB, NumInstrs,
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Prediction, Confidence);
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return NumInstrs && NumInstrs <= 3;
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}
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bool Thumb2InstrInfo::
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isProfitableToIfCvt(MachineBasicBlock &TMBB, unsigned NumT,
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MachineBasicBlock &FMBB, unsigned NumF,
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float Prediction, float Confidence) const {
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if (!OldT2IfCvt)
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return ARMBaseInstrInfo::isProfitableToIfCvt(TMBB, NumT,
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FMBB, NumF,
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Prediction, Confidence);
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// FIXME: Catch optimization such as:
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// r0 = movne
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// r0 = moveq
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return NumT && NumF &&
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NumT <= 3 && NumF <= 3;
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}
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void
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Thumb2InstrInfo::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
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MachineBasicBlock *NewDest) const {
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MachineBasicBlock *MBB = Tail->getParent();
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ARMFunctionInfo *AFI = MBB->getParent()->getInfo<ARMFunctionInfo>();
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if (!AFI->hasITBlocks()) {
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TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
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return;
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}
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// If the first instruction of Tail is predicated, we may have to update
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// the IT instruction.
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unsigned PredReg = 0;
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ARMCC::CondCodes CC = llvm::getInstrPredicate(Tail, PredReg);
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MachineBasicBlock::iterator MBBI = Tail;
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if (CC != ARMCC::AL)
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// Expecting at least the t2IT instruction before it.
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--MBBI;
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// Actually replace the tail.
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TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
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// Fix up IT.
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if (CC != ARMCC::AL) {
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MachineBasicBlock::iterator E = MBB->begin();
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unsigned Count = 4; // At most 4 instructions in an IT block.
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while (Count && MBBI != E) {
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if (MBBI->isDebugValue()) {
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--MBBI;
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continue;
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}
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if (MBBI->getOpcode() == ARM::t2IT) {
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unsigned Mask = MBBI->getOperand(1).getImm();
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if (Count == 4)
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MBBI->eraseFromParent();
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else {
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unsigned MaskOn = 1 << Count;
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unsigned MaskOff = ~(MaskOn - 1);
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MBBI->getOperand(1).setImm((Mask & MaskOff) | MaskOn);
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}
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return;
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}
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--MBBI;
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--Count;
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}
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// Ctrl flow can reach here if branch folding is run before IT block
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// formation pass.
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}
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}
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bool
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Thumb2InstrInfo::isLegalToSplitMBBAt(MachineBasicBlock &MBB,
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MachineBasicBlock::iterator MBBI) const {
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unsigned PredReg = 0;
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return llvm::getITInstrPredicate(MBBI, PredReg) == ARMCC::AL;
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}
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void Thumb2InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
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MachineBasicBlock::iterator I, DebugLoc DL,
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unsigned DestReg, unsigned SrcReg,
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bool KillSrc) const {
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// Handle SPR, DPR, and QPR copies.
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if (!ARM::GPRRegClass.contains(DestReg, SrcReg))
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return ARMBaseInstrInfo::copyPhysReg(MBB, I, DL, DestReg, SrcReg, KillSrc);
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bool tDest = ARM::tGPRRegClass.contains(DestReg);
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bool tSrc = ARM::tGPRRegClass.contains(SrcReg);
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unsigned Opc = ARM::tMOVgpr2gpr;
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if (tDest && tSrc)
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Opc = ARM::tMOVr;
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else if (tSrc)
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Opc = ARM::tMOVtgpr2gpr;
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else if (tDest)
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Opc = ARM::tMOVgpr2tgpr;
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BuildMI(MBB, I, DL, get(Opc), DestReg)
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.addReg(SrcReg, getKillRegState(KillSrc));
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}
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void Thumb2InstrInfo::
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storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
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unsigned SrcReg, bool isKill, int FI,
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const TargetRegisterClass *RC,
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const TargetRegisterInfo *TRI) const {
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if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
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RC == ARM::tcGPRRegisterClass || RC == ARM::rGPRRegisterClass) {
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DebugLoc DL;
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if (I != MBB.end()) DL = I->getDebugLoc();
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MachineFunction &MF = *MBB.getParent();
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MachineFrameInfo &MFI = *MF.getFrameInfo();
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MachineMemOperand *MMO =
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MF.getMachineMemOperand(
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MachinePointerInfo(PseudoSourceValue::getFixedStack(FI)),
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MachineMemOperand::MOStore,
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MFI.getObjectSize(FI),
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MFI.getObjectAlignment(FI));
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AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2STRi12))
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.addReg(SrcReg, getKillRegState(isKill))
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.addFrameIndex(FI).addImm(0).addMemOperand(MMO));
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return;
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}
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ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI);
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}
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void Thumb2InstrInfo::
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loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
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unsigned DestReg, int FI,
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const TargetRegisterClass *RC,
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const TargetRegisterInfo *TRI) const {
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if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
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RC == ARM::tcGPRRegisterClass || RC == ARM::rGPRRegisterClass) {
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DebugLoc DL;
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if (I != MBB.end()) DL = I->getDebugLoc();
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MachineFunction &MF = *MBB.getParent();
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MachineFrameInfo &MFI = *MF.getFrameInfo();
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MachineMemOperand *MMO =
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MF.getMachineMemOperand(
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MachinePointerInfo(PseudoSourceValue::getFixedStack(FI)),
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MachineMemOperand::MOLoad,
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MFI.getObjectSize(FI),
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MFI.getObjectAlignment(FI));
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AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg)
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.addFrameIndex(FI).addImm(0).addMemOperand(MMO));
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return;
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}
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ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI);
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}
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ScheduleHazardRecognizer *Thumb2InstrInfo::
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CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II) const {
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return (ScheduleHazardRecognizer *)new Thumb2HazardRecognizer(II);
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}
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void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
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MachineBasicBlock::iterator &MBBI, DebugLoc dl,
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unsigned DestReg, unsigned BaseReg, int NumBytes,
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ARMCC::CondCodes Pred, unsigned PredReg,
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const ARMBaseInstrInfo &TII) {
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bool isSub = NumBytes < 0;
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if (isSub) NumBytes = -NumBytes;
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// If profitable, use a movw or movt to materialize the offset.
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// FIXME: Use the scavenger to grab a scratch register.
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if (DestReg != ARM::SP && DestReg != BaseReg &&
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NumBytes >= 4096 &&
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ARM_AM::getT2SOImmVal(NumBytes) == -1) {
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bool Fits = false;
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if (NumBytes < 65536) {
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// Use a movw to materialize the 16-bit constant.
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BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg)
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.addImm(NumBytes)
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.addImm((unsigned)Pred).addReg(PredReg);
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Fits = true;
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} else if ((NumBytes & 0xffff) == 0) {
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// Use a movt to materialize the 32-bit constant.
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BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg)
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.addReg(DestReg)
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.addImm(NumBytes >> 16)
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.addImm((unsigned)Pred).addReg(PredReg);
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Fits = true;
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}
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if (Fits) {
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if (isSub) {
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BuildMI(MBB, MBBI, dl, TII.get(ARM::t2SUBrr), DestReg)
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.addReg(BaseReg, RegState::Kill)
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.addReg(DestReg, RegState::Kill)
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.addImm((unsigned)Pred).addReg(PredReg).addReg(0);
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} else {
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BuildMI(MBB, MBBI, dl, TII.get(ARM::t2ADDrr), DestReg)
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.addReg(DestReg, RegState::Kill)
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.addReg(BaseReg, RegState::Kill)
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.addImm((unsigned)Pred).addReg(PredReg).addReg(0);
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}
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return;
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}
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}
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while (NumBytes) {
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unsigned ThisVal = NumBytes;
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unsigned Opc = 0;
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if (DestReg == ARM::SP && BaseReg != ARM::SP) {
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// mov sp, rn. Note t2MOVr cannot be used.
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BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr),DestReg).addReg(BaseReg);
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BaseReg = ARM::SP;
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continue;
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}
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bool HasCCOut = true;
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if (BaseReg == ARM::SP) {
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// sub sp, sp, #imm7
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if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
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assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?");
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Opc = isSub ? ARM::tSUBspi : ARM::tADDspi;
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// FIXME: Fix Thumb1 immediate encoding.
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BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
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.addReg(BaseReg).addImm(ThisVal/4);
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NumBytes = 0;
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continue;
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}
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// sub rd, sp, so_imm
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Opc = isSub ? ARM::t2SUBrSPi : ARM::t2ADDrSPi;
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if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
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NumBytes = 0;
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} else {
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// FIXME: Move this to ARMAddressingModes.h?
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unsigned RotAmt = CountLeadingZeros_32(ThisVal);
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ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
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NumBytes &= ~ThisVal;
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assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
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"Bit extraction didn't work?");
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}
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} else {
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assert(DestReg != ARM::SP && BaseReg != ARM::SP);
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Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri;
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if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
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NumBytes = 0;
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} else if (ThisVal < 4096) {
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Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
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HasCCOut = false;
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NumBytes = 0;
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} else {
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// FIXME: Move this to ARMAddressingModes.h?
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unsigned RotAmt = CountLeadingZeros_32(ThisVal);
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ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
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NumBytes &= ~ThisVal;
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assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
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"Bit extraction didn't work?");
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}
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}
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// Build the new ADD / SUB.
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MachineInstrBuilder MIB =
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AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
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.addReg(BaseReg, RegState::Kill)
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.addImm(ThisVal));
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if (HasCCOut)
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AddDefaultCC(MIB);
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BaseReg = DestReg;
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}
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}
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static unsigned
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negativeOffsetOpcode(unsigned opcode)
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{
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switch (opcode) {
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case ARM::t2LDRi12: return ARM::t2LDRi8;
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case ARM::t2LDRHi12: return ARM::t2LDRHi8;
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case ARM::t2LDRBi12: return ARM::t2LDRBi8;
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case ARM::t2LDRSHi12: return ARM::t2LDRSHi8;
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case ARM::t2LDRSBi12: return ARM::t2LDRSBi8;
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case ARM::t2STRi12: return ARM::t2STRi8;
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case ARM::t2STRBi12: return ARM::t2STRBi8;
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case ARM::t2STRHi12: return ARM::t2STRHi8;
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case ARM::t2LDRi8:
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case ARM::t2LDRHi8:
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case ARM::t2LDRBi8:
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case ARM::t2LDRSHi8:
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case ARM::t2LDRSBi8:
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case ARM::t2STRi8:
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case ARM::t2STRBi8:
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case ARM::t2STRHi8:
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return opcode;
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default:
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break;
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}
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return 0;
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}
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static unsigned
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positiveOffsetOpcode(unsigned opcode)
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{
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switch (opcode) {
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case ARM::t2LDRi8: return ARM::t2LDRi12;
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case ARM::t2LDRHi8: return ARM::t2LDRHi12;
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case ARM::t2LDRBi8: return ARM::t2LDRBi12;
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case ARM::t2LDRSHi8: return ARM::t2LDRSHi12;
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case ARM::t2LDRSBi8: return ARM::t2LDRSBi12;
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case ARM::t2STRi8: return ARM::t2STRi12;
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case ARM::t2STRBi8: return ARM::t2STRBi12;
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case ARM::t2STRHi8: return ARM::t2STRHi12;
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case ARM::t2LDRi12:
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case ARM::t2LDRHi12:
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case ARM::t2LDRBi12:
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case ARM::t2LDRSHi12:
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case ARM::t2LDRSBi12:
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case ARM::t2STRi12:
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case ARM::t2STRBi12:
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case ARM::t2STRHi12:
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return opcode;
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default:
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break;
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}
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return 0;
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}
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static unsigned
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immediateOffsetOpcode(unsigned opcode)
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{
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switch (opcode) {
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case ARM::t2LDRs: return ARM::t2LDRi12;
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case ARM::t2LDRHs: return ARM::t2LDRHi12;
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case ARM::t2LDRBs: return ARM::t2LDRBi12;
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case ARM::t2LDRSHs: return ARM::t2LDRSHi12;
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case ARM::t2LDRSBs: return ARM::t2LDRSBi12;
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case ARM::t2STRs: return ARM::t2STRi12;
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case ARM::t2STRBs: return ARM::t2STRBi12;
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case ARM::t2STRHs: return ARM::t2STRHi12;
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case ARM::t2LDRi12:
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case ARM::t2LDRHi12:
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case ARM::t2LDRBi12:
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case ARM::t2LDRSHi12:
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case ARM::t2LDRSBi12:
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case ARM::t2STRi12:
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case ARM::t2STRBi12:
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case ARM::t2STRHi12:
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case ARM::t2LDRi8:
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case ARM::t2LDRHi8:
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case ARM::t2LDRBi8:
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case ARM::t2LDRSHi8:
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case ARM::t2LDRSBi8:
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case ARM::t2STRi8:
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case ARM::t2STRBi8:
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case ARM::t2STRHi8:
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return opcode;
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default:
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break;
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}
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return 0;
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}
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bool llvm::rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
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unsigned FrameReg, int &Offset,
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const ARMBaseInstrInfo &TII) {
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unsigned Opcode = MI.getOpcode();
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const TargetInstrDesc &Desc = MI.getDesc();
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unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
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bool isSub = false;
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// Memory operands in inline assembly always use AddrModeT2_i12.
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if (Opcode == ARM::INLINEASM)
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AddrMode = ARMII::AddrModeT2_i12; // FIXME. mode for thumb2?
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if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) {
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Offset += MI.getOperand(FrameRegIdx+1).getImm();
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unsigned PredReg;
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if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) {
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// Turn it into a move.
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MI.setDesc(TII.get(ARM::tMOVgpr2gpr));
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MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
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// Remove offset and remaining explicit predicate operands.
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do MI.RemoveOperand(FrameRegIdx+1);
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while (MI.getNumOperands() > FrameRegIdx+1 &&
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(!MI.getOperand(FrameRegIdx+1).isReg() ||
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!MI.getOperand(FrameRegIdx+1).isImm()));
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return true;
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}
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bool isSP = FrameReg == ARM::SP;
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bool HasCCOut = Opcode != ARM::t2ADDri12;
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if (Offset < 0) {
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Offset = -Offset;
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isSub = true;
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MI.setDesc(TII.get(isSP ? ARM::t2SUBrSPi : ARM::t2SUBri));
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} else {
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MI.setDesc(TII.get(isSP ? ARM::t2ADDrSPi : ARM::t2ADDri));
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}
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// Common case: small offset, fits into instruction.
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if (ARM_AM::getT2SOImmVal(Offset) != -1) {
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MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
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MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
|
|
// Add cc_out operand if the original instruction did not have one.
|
|
if (!HasCCOut)
|
|
MI.addOperand(MachineOperand::CreateReg(0, false));
|
|
Offset = 0;
|
|
return true;
|
|
}
|
|
// Another common case: imm12.
|
|
if (Offset < 4096 &&
|
|
(!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) {
|
|
unsigned NewOpc = isSP
|
|
? (isSub ? ARM::t2SUBrSPi12 : ARM::t2ADDrSPi12)
|
|
: (isSub ? ARM::t2SUBri12 : ARM::t2ADDri12);
|
|
MI.setDesc(TII.get(NewOpc));
|
|
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
|
|
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
|
|
// Remove the cc_out operand.
|
|
if (HasCCOut)
|
|
MI.RemoveOperand(MI.getNumOperands()-1);
|
|
Offset = 0;
|
|
return true;
|
|
}
|
|
|
|
// Otherwise, extract 8 adjacent bits from the immediate into this
|
|
// t2ADDri/t2SUBri.
|
|
unsigned RotAmt = CountLeadingZeros_32(Offset);
|
|
unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xff000000U, RotAmt);
|
|
|
|
// We will handle these bits from offset, clear them.
|
|
Offset &= ~ThisImmVal;
|
|
|
|
assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 &&
|
|
"Bit extraction didn't work?");
|
|
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
|
|
// Add cc_out operand if the original instruction did not have one.
|
|
if (!HasCCOut)
|
|
MI.addOperand(MachineOperand::CreateReg(0, false));
|
|
|
|
} else {
|
|
|
|
// AddrMode4 and AddrMode6 cannot handle any offset.
|
|
if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
|
|
return false;
|
|
|
|
// AddrModeT2_so cannot handle any offset. If there is no offset
|
|
// register then we change to an immediate version.
|
|
unsigned NewOpc = Opcode;
|
|
if (AddrMode == ARMII::AddrModeT2_so) {
|
|
unsigned OffsetReg = MI.getOperand(FrameRegIdx+1).getReg();
|
|
if (OffsetReg != 0) {
|
|
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
|
|
return Offset == 0;
|
|
}
|
|
|
|
MI.RemoveOperand(FrameRegIdx+1);
|
|
MI.getOperand(FrameRegIdx+1).ChangeToImmediate(0);
|
|
NewOpc = immediateOffsetOpcode(Opcode);
|
|
AddrMode = ARMII::AddrModeT2_i12;
|
|
}
|
|
|
|
unsigned NumBits = 0;
|
|
unsigned Scale = 1;
|
|
if (AddrMode == ARMII::AddrModeT2_i8 || AddrMode == ARMII::AddrModeT2_i12) {
|
|
// i8 supports only negative, and i12 supports only positive, so
|
|
// based on Offset sign convert Opcode to the appropriate
|
|
// instruction
|
|
Offset += MI.getOperand(FrameRegIdx+1).getImm();
|
|
if (Offset < 0) {
|
|
NewOpc = negativeOffsetOpcode(Opcode);
|
|
NumBits = 8;
|
|
isSub = true;
|
|
Offset = -Offset;
|
|
} else {
|
|
NewOpc = positiveOffsetOpcode(Opcode);
|
|
NumBits = 12;
|
|
}
|
|
} else if (AddrMode == ARMII::AddrMode5) {
|
|
// VFP address mode.
|
|
const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
|
|
int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
|
|
if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
|
|
InstrOffs *= -1;
|
|
NumBits = 8;
|
|
Scale = 4;
|
|
Offset += InstrOffs * 4;
|
|
assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
|
|
if (Offset < 0) {
|
|
Offset = -Offset;
|
|
isSub = true;
|
|
}
|
|
} else {
|
|
llvm_unreachable("Unsupported addressing mode!");
|
|
}
|
|
|
|
if (NewOpc != Opcode)
|
|
MI.setDesc(TII.get(NewOpc));
|
|
|
|
MachineOperand &ImmOp = MI.getOperand(FrameRegIdx+1);
|
|
|
|
// Attempt to fold address computation
|
|
// Common case: small offset, fits into instruction.
|
|
int ImmedOffset = Offset / Scale;
|
|
unsigned Mask = (1 << NumBits) - 1;
|
|
if ((unsigned)Offset <= Mask * Scale) {
|
|
// Replace the FrameIndex with fp/sp
|
|
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
|
|
if (isSub) {
|
|
if (AddrMode == ARMII::AddrMode5)
|
|
// FIXME: Not consistent.
|
|
ImmedOffset |= 1 << NumBits;
|
|
else
|
|
ImmedOffset = -ImmedOffset;
|
|
}
|
|
ImmOp.ChangeToImmediate(ImmedOffset);
|
|
Offset = 0;
|
|
return true;
|
|
}
|
|
|
|
// Otherwise, offset doesn't fit. Pull in what we can to simplify
|
|
ImmedOffset = ImmedOffset & Mask;
|
|
if (isSub) {
|
|
if (AddrMode == ARMII::AddrMode5)
|
|
// FIXME: Not consistent.
|
|
ImmedOffset |= 1 << NumBits;
|
|
else {
|
|
ImmedOffset = -ImmedOffset;
|
|
if (ImmedOffset == 0)
|
|
// Change the opcode back if the encoded offset is zero.
|
|
MI.setDesc(TII.get(positiveOffsetOpcode(NewOpc)));
|
|
}
|
|
}
|
|
ImmOp.ChangeToImmediate(ImmedOffset);
|
|
Offset &= ~(Mask*Scale);
|
|
}
|
|
|
|
Offset = (isSub) ? -Offset : Offset;
|
|
return Offset == 0;
|
|
}
|
|
|
|
/// scheduleTwoAddrSource - Schedule the copy / re-mat of the source of the
|
|
/// two-addrss instruction inserted by two-address pass.
|
|
void
|
|
Thumb2InstrInfo::scheduleTwoAddrSource(MachineInstr *SrcMI,
|
|
MachineInstr *UseMI,
|
|
const TargetRegisterInfo &TRI) const {
|
|
if (SrcMI->getOpcode() != ARM::tMOVgpr2gpr ||
|
|
SrcMI->getOperand(1).isKill())
|
|
return;
|
|
|
|
unsigned PredReg = 0;
|
|
ARMCC::CondCodes CC = llvm::getInstrPredicate(UseMI, PredReg);
|
|
if (CC == ARMCC::AL || PredReg != ARM::CPSR)
|
|
return;
|
|
|
|
// Schedule the copy so it doesn't come between previous instructions
|
|
// and UseMI which can form an IT block.
|
|
unsigned SrcReg = SrcMI->getOperand(1).getReg();
|
|
ARMCC::CondCodes OCC = ARMCC::getOppositeCondition(CC);
|
|
MachineBasicBlock *MBB = UseMI->getParent();
|
|
MachineBasicBlock::iterator MBBI = SrcMI;
|
|
unsigned NumInsts = 0;
|
|
while (--MBBI != MBB->begin()) {
|
|
if (MBBI->isDebugValue())
|
|
continue;
|
|
|
|
MachineInstr *NMI = &*MBBI;
|
|
ARMCC::CondCodes NCC = llvm::getInstrPredicate(NMI, PredReg);
|
|
if (!(NCC == CC || NCC == OCC) ||
|
|
NMI->modifiesRegister(SrcReg, &TRI) ||
|
|
NMI->definesRegister(ARM::CPSR))
|
|
break;
|
|
if (++NumInsts == 4)
|
|
// Too many in a row!
|
|
return;
|
|
}
|
|
|
|
if (NumInsts) {
|
|
MBB->remove(SrcMI);
|
|
MBB->insert(++MBBI, SrcMI);
|
|
}
|
|
}
|
|
|
|
ARMCC::CondCodes
|
|
llvm::getITInstrPredicate(const MachineInstr *MI, unsigned &PredReg) {
|
|
unsigned Opc = MI->getOpcode();
|
|
if (Opc == ARM::tBcc || Opc == ARM::t2Bcc)
|
|
return ARMCC::AL;
|
|
return llvm::getInstrPredicate(MI, PredReg);
|
|
}
|