mirror of
https://github.com/jeremysrand/llvm-65816.git
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550 lines
20 KiB
C++
550 lines
20 KiB
C++
//===-- MipsSEFrameLowering.cpp - Mips32/64 Frame Information -------------===//
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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 Mips32/64 implementation of TargetFrameLowering class.
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//
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//===----------------------------------------------------------------------===//
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#include "MipsSEFrameLowering.h"
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#include "MCTargetDesc/MipsBaseInfo.h"
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#include "MipsAnalyzeImmediate.h"
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#include "MipsMachineFunction.h"
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#include "MipsSEInstrInfo.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineModuleInfo.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/RegisterScavenging.h"
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#include "llvm/IR/DataLayout.h"
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#include "llvm/IR/Function.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Target/TargetOptions.h"
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using namespace llvm;
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namespace {
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typedef MachineBasicBlock::iterator Iter;
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static std::pair<unsigned, unsigned> getMFHiLoOpc(unsigned Src) {
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if (Mips::ACC64RegClass.contains(Src))
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return std::make_pair((unsigned)Mips::PseudoMFHI,
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(unsigned)Mips::PseudoMFLO);
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if (Mips::ACC64DSPRegClass.contains(Src))
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return std::make_pair((unsigned)Mips::MFHI_DSP, (unsigned)Mips::MFLO_DSP);
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if (Mips::ACC128RegClass.contains(Src))
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return std::make_pair((unsigned)Mips::PseudoMFHI64,
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(unsigned)Mips::PseudoMFLO64);
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return std::make_pair(0, 0);
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}
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/// Helper class to expand pseudos.
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class ExpandPseudo {
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public:
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ExpandPseudo(MachineFunction &MF);
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bool expand();
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private:
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bool expandInstr(MachineBasicBlock &MBB, Iter I);
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void expandLoadCCond(MachineBasicBlock &MBB, Iter I);
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void expandStoreCCond(MachineBasicBlock &MBB, Iter I);
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void expandLoadACC(MachineBasicBlock &MBB, Iter I, unsigned RegSize);
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void expandStoreACC(MachineBasicBlock &MBB, Iter I, unsigned MFHiOpc,
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unsigned MFLoOpc, unsigned RegSize);
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bool expandCopy(MachineBasicBlock &MBB, Iter I);
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bool expandCopyACC(MachineBasicBlock &MBB, Iter I, unsigned MFHiOpc,
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unsigned MFLoOpc);
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MachineFunction &MF;
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MachineRegisterInfo &MRI;
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};
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}
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ExpandPseudo::ExpandPseudo(MachineFunction &MF_)
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: MF(MF_), MRI(MF.getRegInfo()) {}
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bool ExpandPseudo::expand() {
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bool Expanded = false;
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for (MachineFunction::iterator BB = MF.begin(), BBEnd = MF.end();
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BB != BBEnd; ++BB)
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for (Iter I = BB->begin(), End = BB->end(); I != End;)
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Expanded |= expandInstr(*BB, I++);
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return Expanded;
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}
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bool ExpandPseudo::expandInstr(MachineBasicBlock &MBB, Iter I) {
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switch(I->getOpcode()) {
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case Mips::LOAD_CCOND_DSP:
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expandLoadCCond(MBB, I);
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break;
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case Mips::STORE_CCOND_DSP:
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expandStoreCCond(MBB, I);
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break;
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case Mips::LOAD_ACC64:
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case Mips::LOAD_ACC64DSP:
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expandLoadACC(MBB, I, 4);
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break;
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case Mips::LOAD_ACC128:
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expandLoadACC(MBB, I, 8);
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break;
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case Mips::STORE_ACC64:
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expandStoreACC(MBB, I, Mips::PseudoMFHI, Mips::PseudoMFLO, 4);
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break;
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case Mips::STORE_ACC64DSP:
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expandStoreACC(MBB, I, Mips::MFHI_DSP, Mips::MFLO_DSP, 4);
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break;
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case Mips::STORE_ACC128:
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expandStoreACC(MBB, I, Mips::PseudoMFHI64, Mips::PseudoMFLO64, 8);
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break;
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case TargetOpcode::COPY:
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if (!expandCopy(MBB, I))
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return false;
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break;
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default:
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return false;
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}
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MBB.erase(I);
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return true;
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}
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void ExpandPseudo::expandLoadCCond(MachineBasicBlock &MBB, Iter I) {
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// load $vr, FI
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// copy ccond, $vr
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assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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const TargetRegisterClass *RC = RegInfo.intRegClass(4);
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unsigned VR = MRI.createVirtualRegister(RC);
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unsigned Dst = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
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TII.loadRegFromStack(MBB, I, VR, FI, RC, &RegInfo, 0);
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BuildMI(MBB, I, I->getDebugLoc(), TII.get(TargetOpcode::COPY), Dst)
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.addReg(VR, RegState::Kill);
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}
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void ExpandPseudo::expandStoreCCond(MachineBasicBlock &MBB, Iter I) {
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// copy $vr, ccond
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// store $vr, FI
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assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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const TargetRegisterClass *RC = RegInfo.intRegClass(4);
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unsigned VR = MRI.createVirtualRegister(RC);
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unsigned Src = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
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BuildMI(MBB, I, I->getDebugLoc(), TII.get(TargetOpcode::COPY), VR)
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.addReg(Src, getKillRegState(I->getOperand(0).isKill()));
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TII.storeRegToStack(MBB, I, VR, true, FI, RC, &RegInfo, 0);
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}
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void ExpandPseudo::expandLoadACC(MachineBasicBlock &MBB, Iter I,
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unsigned RegSize) {
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// load $vr0, FI
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// copy lo, $vr0
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// load $vr1, FI + 4
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// copy hi, $vr1
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assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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const TargetRegisterClass *RC = RegInfo.intRegClass(RegSize);
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unsigned VR0 = MRI.createVirtualRegister(RC);
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unsigned VR1 = MRI.createVirtualRegister(RC);
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unsigned Dst = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
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unsigned Lo = RegInfo.getSubReg(Dst, Mips::sub_lo);
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unsigned Hi = RegInfo.getSubReg(Dst, Mips::sub_hi);
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DebugLoc DL = I->getDebugLoc();
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const MCInstrDesc &Desc = TII.get(TargetOpcode::COPY);
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TII.loadRegFromStack(MBB, I, VR0, FI, RC, &RegInfo, 0);
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BuildMI(MBB, I, DL, Desc, Lo).addReg(VR0, RegState::Kill);
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TII.loadRegFromStack(MBB, I, VR1, FI, RC, &RegInfo, RegSize);
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BuildMI(MBB, I, DL, Desc, Hi).addReg(VR1, RegState::Kill);
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}
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void ExpandPseudo::expandStoreACC(MachineBasicBlock &MBB, Iter I,
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unsigned MFHiOpc, unsigned MFLoOpc,
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unsigned RegSize) {
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// mflo $vr0, src
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// store $vr0, FI
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// mfhi $vr1, src
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// store $vr1, FI + 4
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assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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const TargetRegisterClass *RC = RegInfo.intRegClass(RegSize);
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unsigned VR0 = MRI.createVirtualRegister(RC);
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unsigned VR1 = MRI.createVirtualRegister(RC);
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unsigned Src = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
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unsigned SrcKill = getKillRegState(I->getOperand(0).isKill());
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DebugLoc DL = I->getDebugLoc();
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BuildMI(MBB, I, DL, TII.get(MFLoOpc), VR0).addReg(Src);
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TII.storeRegToStack(MBB, I, VR0, true, FI, RC, &RegInfo, 0);
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BuildMI(MBB, I, DL, TII.get(MFHiOpc), VR1).addReg(Src, SrcKill);
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TII.storeRegToStack(MBB, I, VR1, true, FI, RC, &RegInfo, RegSize);
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}
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bool ExpandPseudo::expandCopy(MachineBasicBlock &MBB, Iter I) {
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unsigned Src = I->getOperand(1).getReg();
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std::pair<unsigned, unsigned> Opcodes = getMFHiLoOpc(Src);
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if (!Opcodes.first)
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return false;
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return expandCopyACC(MBB, I, Opcodes.first, Opcodes.second);
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}
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bool ExpandPseudo::expandCopyACC(MachineBasicBlock &MBB, Iter I,
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unsigned MFHiOpc, unsigned MFLoOpc) {
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// mflo $vr0, src
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// copy dst_lo, $vr0
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// mfhi $vr1, src
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// copy dst_hi, $vr1
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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unsigned Dst = I->getOperand(0).getReg(), Src = I->getOperand(1).getReg();
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unsigned VRegSize = RegInfo.getMinimalPhysRegClass(Dst)->getSize() / 2;
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const TargetRegisterClass *RC = RegInfo.intRegClass(VRegSize);
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unsigned VR0 = MRI.createVirtualRegister(RC);
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unsigned VR1 = MRI.createVirtualRegister(RC);
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unsigned SrcKill = getKillRegState(I->getOperand(1).isKill());
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unsigned DstLo = RegInfo.getSubReg(Dst, Mips::sub_lo);
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unsigned DstHi = RegInfo.getSubReg(Dst, Mips::sub_hi);
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DebugLoc DL = I->getDebugLoc();
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BuildMI(MBB, I, DL, TII.get(MFLoOpc), VR0).addReg(Src);
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BuildMI(MBB, I, DL, TII.get(TargetOpcode::COPY), DstLo)
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.addReg(VR0, RegState::Kill);
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BuildMI(MBB, I, DL, TII.get(MFHiOpc), VR1).addReg(Src, SrcKill);
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BuildMI(MBB, I, DL, TII.get(TargetOpcode::COPY), DstHi)
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.addReg(VR1, RegState::Kill);
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return true;
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}
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unsigned MipsSEFrameLowering::ehDataReg(unsigned I) const {
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static const unsigned EhDataReg[] = {
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Mips::A0, Mips::A1, Mips::A2, Mips::A3
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};
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static const unsigned EhDataReg64[] = {
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Mips::A0_64, Mips::A1_64, Mips::A2_64, Mips::A3_64
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};
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return STI.isABI_N64() ? EhDataReg64[I] : EhDataReg[I];
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}
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void MipsSEFrameLowering::emitPrologue(MachineFunction &MF) const {
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MachineBasicBlock &MBB = MF.front();
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MachineFrameInfo *MFI = MF.getFrameInfo();
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MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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MachineBasicBlock::iterator MBBI = MBB.begin();
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DebugLoc dl = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
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unsigned SP = STI.isABI_N64() ? Mips::SP_64 : Mips::SP;
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unsigned FP = STI.isABI_N64() ? Mips::FP_64 : Mips::FP;
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unsigned ZERO = STI.isABI_N64() ? Mips::ZERO_64 : Mips::ZERO;
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unsigned ADDu = STI.isABI_N64() ? Mips::DADDu : Mips::ADDu;
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// First, compute final stack size.
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uint64_t StackSize = MFI->getStackSize();
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// No need to allocate space on the stack.
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if (StackSize == 0 && !MFI->adjustsStack()) return;
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MachineModuleInfo &MMI = MF.getMMI();
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const MCRegisterInfo *MRI = MMI.getContext().getRegisterInfo();
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MachineLocation DstML, SrcML;
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// Adjust stack.
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TII.adjustStackPtr(SP, -StackSize, MBB, MBBI);
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// emit ".cfi_def_cfa_offset StackSize"
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MCSymbol *AdjustSPLabel = MMI.getContext().CreateTempSymbol();
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BuildMI(MBB, MBBI, dl,
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TII.get(TargetOpcode::PROLOG_LABEL)).addSym(AdjustSPLabel);
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MMI.addFrameInst(
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MCCFIInstruction::createDefCfaOffset(AdjustSPLabel, -StackSize));
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const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
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if (CSI.size()) {
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// Find the instruction past the last instruction that saves a callee-saved
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// register to the stack.
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for (unsigned i = 0; i < CSI.size(); ++i)
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++MBBI;
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// Iterate over list of callee-saved registers and emit .cfi_offset
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// directives.
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MCSymbol *CSLabel = MMI.getContext().CreateTempSymbol();
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BuildMI(MBB, MBBI, dl,
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TII.get(TargetOpcode::PROLOG_LABEL)).addSym(CSLabel);
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for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
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E = CSI.end(); I != E; ++I) {
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int64_t Offset = MFI->getObjectOffset(I->getFrameIdx());
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unsigned Reg = I->getReg();
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// If Reg is a double precision register, emit two cfa_offsets,
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// one for each of the paired single precision registers.
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if (Mips::AFGR64RegClass.contains(Reg)) {
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unsigned Reg0 =
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MRI->getDwarfRegNum(RegInfo.getSubReg(Reg, Mips::sub_lo), true);
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unsigned Reg1 =
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MRI->getDwarfRegNum(RegInfo.getSubReg(Reg, Mips::sub_hi), true);
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if (!STI.isLittle())
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std::swap(Reg0, Reg1);
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MMI.addFrameInst(
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MCCFIInstruction::createOffset(CSLabel, Reg0, Offset));
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MMI.addFrameInst(
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MCCFIInstruction::createOffset(CSLabel, Reg1, Offset + 4));
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} else {
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// Reg is either in GPR32 or FGR32.
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MMI.addFrameInst(MCCFIInstruction::createOffset(
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CSLabel, MRI->getDwarfRegNum(Reg, 1), Offset));
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}
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}
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}
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if (MipsFI->callsEhReturn()) {
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const TargetRegisterClass *RC = STI.isABI_N64() ?
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&Mips::GPR64RegClass : &Mips::GPR32RegClass;
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// Insert instructions that spill eh data registers.
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for (int I = 0; I < 4; ++I) {
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if (!MBB.isLiveIn(ehDataReg(I)))
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MBB.addLiveIn(ehDataReg(I));
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TII.storeRegToStackSlot(MBB, MBBI, ehDataReg(I), false,
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MipsFI->getEhDataRegFI(I), RC, &RegInfo);
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}
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// Emit .cfi_offset directives for eh data registers.
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MCSymbol *CSLabel2 = MMI.getContext().CreateTempSymbol();
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BuildMI(MBB, MBBI, dl,
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TII.get(TargetOpcode::PROLOG_LABEL)).addSym(CSLabel2);
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for (int I = 0; I < 4; ++I) {
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int64_t Offset = MFI->getObjectOffset(MipsFI->getEhDataRegFI(I));
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unsigned Reg = MRI->getDwarfRegNum(ehDataReg(I), true);
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MMI.addFrameInst(MCCFIInstruction::createOffset(CSLabel2, Reg, Offset));
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}
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}
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// if framepointer enabled, set it to point to the stack pointer.
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if (hasFP(MF)) {
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// Insert instruction "move $fp, $sp" at this location.
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BuildMI(MBB, MBBI, dl, TII.get(ADDu), FP).addReg(SP).addReg(ZERO);
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// emit ".cfi_def_cfa_register $fp"
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MCSymbol *SetFPLabel = MMI.getContext().CreateTempSymbol();
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BuildMI(MBB, MBBI, dl,
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TII.get(TargetOpcode::PROLOG_LABEL)).addSym(SetFPLabel);
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MMI.addFrameInst(MCCFIInstruction::createDefCfaRegister(
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SetFPLabel, MRI->getDwarfRegNum(FP, true)));
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}
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}
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void MipsSEFrameLowering::emitEpilogue(MachineFunction &MF,
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MachineBasicBlock &MBB) const {
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MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
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MachineFrameInfo *MFI = MF.getFrameInfo();
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MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
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const MipsSEInstrInfo &TII =
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*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
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const MipsRegisterInfo &RegInfo =
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*static_cast<const MipsRegisterInfo*>(MF.getTarget().getRegisterInfo());
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DebugLoc dl = MBBI->getDebugLoc();
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unsigned SP = STI.isABI_N64() ? Mips::SP_64 : Mips::SP;
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unsigned FP = STI.isABI_N64() ? Mips::FP_64 : Mips::FP;
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unsigned ZERO = STI.isABI_N64() ? Mips::ZERO_64 : Mips::ZERO;
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unsigned ADDu = STI.isABI_N64() ? Mips::DADDu : Mips::ADDu;
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// if framepointer enabled, restore the stack pointer.
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if (hasFP(MF)) {
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// Find the first instruction that restores a callee-saved register.
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MachineBasicBlock::iterator I = MBBI;
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for (unsigned i = 0; i < MFI->getCalleeSavedInfo().size(); ++i)
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--I;
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// Insert instruction "move $sp, $fp" at this location.
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BuildMI(MBB, I, dl, TII.get(ADDu), SP).addReg(FP).addReg(ZERO);
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}
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if (MipsFI->callsEhReturn()) {
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const TargetRegisterClass *RC = STI.isABI_N64() ?
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&Mips::GPR64RegClass : &Mips::GPR32RegClass;
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// Find first instruction that restores a callee-saved register.
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MachineBasicBlock::iterator I = MBBI;
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for (unsigned i = 0; i < MFI->getCalleeSavedInfo().size(); ++i)
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--I;
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// Insert instructions that restore eh data registers.
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for (int J = 0; J < 4; ++J) {
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TII.loadRegFromStackSlot(MBB, I, ehDataReg(J), MipsFI->getEhDataRegFI(J),
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RC, &RegInfo);
|
|
}
|
|
}
|
|
|
|
// Get the number of bytes from FrameInfo
|
|
uint64_t StackSize = MFI->getStackSize();
|
|
|
|
if (!StackSize)
|
|
return;
|
|
|
|
// Adjust stack.
|
|
TII.adjustStackPtr(SP, StackSize, MBB, MBBI);
|
|
}
|
|
|
|
bool MipsSEFrameLowering::
|
|
spillCalleeSavedRegisters(MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator MI,
|
|
const std::vector<CalleeSavedInfo> &CSI,
|
|
const TargetRegisterInfo *TRI) const {
|
|
MachineFunction *MF = MBB.getParent();
|
|
MachineBasicBlock *EntryBlock = MF->begin();
|
|
const TargetInstrInfo &TII = *MF->getTarget().getInstrInfo();
|
|
|
|
for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
|
|
// Add the callee-saved register as live-in. Do not add if the register is
|
|
// RA and return address is taken, because it has already been added in
|
|
// method MipsTargetLowering::LowerRETURNADDR.
|
|
// It's killed at the spill, unless the register is RA and return address
|
|
// is taken.
|
|
unsigned Reg = CSI[i].getReg();
|
|
bool IsRAAndRetAddrIsTaken = (Reg == Mips::RA || Reg == Mips::RA_64)
|
|
&& MF->getFrameInfo()->isReturnAddressTaken();
|
|
if (!IsRAAndRetAddrIsTaken)
|
|
EntryBlock->addLiveIn(Reg);
|
|
|
|
// Insert the spill to the stack frame.
|
|
bool IsKill = !IsRAAndRetAddrIsTaken;
|
|
const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg);
|
|
TII.storeRegToStackSlot(*EntryBlock, MI, Reg, IsKill,
|
|
CSI[i].getFrameIdx(), RC, TRI);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool
|
|
MipsSEFrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
|
|
const MachineFrameInfo *MFI = MF.getFrameInfo();
|
|
|
|
// Reserve call frame if the size of the maximum call frame fits into 16-bit
|
|
// immediate field and there are no variable sized objects on the stack.
|
|
// Make sure the second register scavenger spill slot can be accessed with one
|
|
// instruction.
|
|
return isInt<16>(MFI->getMaxCallFrameSize() + getStackAlignment()) &&
|
|
!MFI->hasVarSizedObjects();
|
|
}
|
|
|
|
// Eliminate ADJCALLSTACKDOWN, ADJCALLSTACKUP pseudo instructions
|
|
void MipsSEFrameLowering::
|
|
eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
|
|
MachineBasicBlock::iterator I) const {
|
|
const MipsSEInstrInfo &TII =
|
|
*static_cast<const MipsSEInstrInfo*>(MF.getTarget().getInstrInfo());
|
|
|
|
if (!hasReservedCallFrame(MF)) {
|
|
int64_t Amount = I->getOperand(0).getImm();
|
|
|
|
if (I->getOpcode() == Mips::ADJCALLSTACKDOWN)
|
|
Amount = -Amount;
|
|
|
|
unsigned SP = STI.isABI_N64() ? Mips::SP_64 : Mips::SP;
|
|
TII.adjustStackPtr(SP, Amount, MBB, I);
|
|
}
|
|
|
|
MBB.erase(I);
|
|
}
|
|
|
|
void MipsSEFrameLowering::
|
|
processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
|
|
RegScavenger *RS) const {
|
|
MachineRegisterInfo &MRI = MF.getRegInfo();
|
|
MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
|
|
unsigned FP = STI.isABI_N64() ? Mips::FP_64 : Mips::FP;
|
|
|
|
// Mark $fp as used if function has dedicated frame pointer.
|
|
if (hasFP(MF))
|
|
MRI.setPhysRegUsed(FP);
|
|
|
|
// Create spill slots for eh data registers if function calls eh_return.
|
|
if (MipsFI->callsEhReturn())
|
|
MipsFI->createEhDataRegsFI();
|
|
|
|
// Expand pseudo instructions which load, store or copy accumulators.
|
|
// Add an emergency spill slot if a pseudo was expanded.
|
|
if (ExpandPseudo(MF).expand()) {
|
|
// The spill slot should be half the size of the accumulator. If target is
|
|
// mips64, it should be 64-bit, otherwise it should be 32-bt.
|
|
const TargetRegisterClass *RC = STI.hasMips64() ?
|
|
&Mips::GPR64RegClass : &Mips::GPR32RegClass;
|
|
int FI = MF.getFrameInfo()->CreateStackObject(RC->getSize(),
|
|
RC->getAlignment(), false);
|
|
RS->addScavengingFrameIndex(FI);
|
|
}
|
|
|
|
// Set scavenging frame index if necessary.
|
|
uint64_t MaxSPOffset = MF.getInfo<MipsFunctionInfo>()->getIncomingArgSize() +
|
|
estimateStackSize(MF);
|
|
|
|
if (isInt<16>(MaxSPOffset))
|
|
return;
|
|
|
|
const TargetRegisterClass *RC = STI.isABI_N64() ?
|
|
&Mips::GPR64RegClass : &Mips::GPR32RegClass;
|
|
int FI = MF.getFrameInfo()->CreateStackObject(RC->getSize(),
|
|
RC->getAlignment(), false);
|
|
RS->addScavengingFrameIndex(FI);
|
|
}
|
|
|
|
const MipsFrameLowering *
|
|
llvm::createMipsSEFrameLowering(const MipsSubtarget &ST) {
|
|
return new MipsSEFrameLowering(ST);
|
|
}
|