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//===-- Mips/MipsCodeEmitter.cpp - Convert Mips Code to Machine Code ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===---------------------------------------------------------------------===//
//
// This file contains the pass that transforms the Mips machine instructions
// into relocatable machine code.
//
//===---------------------------------------------------------------------===//
#define DEBUG_TYPE "jit"
#include "Mips.h"
#include "MCTargetDesc/MipsBaseInfo.h"
#include "MipsInstrInfo.h"
#include "MipsRelocations.h"
#include "MipsSubtarget.h"
#include "MipsTargetMachine.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/JITCodeEmitter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/PassManager.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#ifndef NDEBUG
#include <iomanip>
#endif
using namespace llvm;
STATISTIC(NumEmitted, "Number of machine instructions emitted");
namespace {
class MipsCodeEmitter : public MachineFunctionPass {
MipsJITInfo *JTI;
const MipsInstrInfo *II;
const DataLayout *TD;
const MipsSubtarget *Subtarget;
TargetMachine &TM;
JITCodeEmitter &MCE;
const std::vector<MachineConstantPoolEntry> *MCPEs;
const std::vector<MachineJumpTableEntry> *MJTEs;
bool IsPIC;
void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<MachineModuleInfo> ();
MachineFunctionPass::getAnalysisUsage(AU);
}
static char ID;
public:
MipsCodeEmitter(TargetMachine &tm, JITCodeEmitter &mce)
: MachineFunctionPass(ID), JTI(0), II(0), TD(0),
TM(tm), MCE(mce), MCPEs(0), MJTEs(0),
IsPIC(TM.getRelocationModel() == Reloc::PIC_) {}
bool runOnMachineFunction(MachineFunction &MF);
virtual const char *getPassName() const {
return "Mips Machine Code Emitter";
}
/// getBinaryCodeForInstr - This function, generated by the
/// CodeEmitterGenerator using TableGen, produces the binary encoding for
/// machine instructions.
uint64_t getBinaryCodeForInstr(const MachineInstr &MI) const;
void emitInstruction(MachineBasicBlock::instr_iterator MI,
MachineBasicBlock &MBB);
private:
void emitWord(unsigned Word);
/// Routines that handle operands which add machine relocations which are
/// fixed up by the relocation stage.
void emitGlobalAddress(const GlobalValue *GV, unsigned Reloc,
bool MayNeedFarStub) const;
void emitExternalSymbolAddress(const char *ES, unsigned Reloc) const;
void emitConstPoolAddress(unsigned CPI, unsigned Reloc) const;
void emitJumpTableAddress(unsigned JTIndex, unsigned Reloc) const;
void emitMachineBasicBlock(MachineBasicBlock *BB, unsigned Reloc) const;
/// getMachineOpValue - Return binary encoding of operand. If the machine
/// operand requires relocation, record the relocation and return zero.
unsigned getMachineOpValue(const MachineInstr &MI,
const MachineOperand &MO) const;
unsigned getRelocation(const MachineInstr &MI,
const MachineOperand &MO) const;
unsigned getJumpTargetOpValue(const MachineInstr &MI, unsigned OpNo) const;
unsigned getBranchTargetOpValue(const MachineInstr &MI, unsigned OpNo) const;
unsigned getMemEncoding(const MachineInstr &MI, unsigned OpNo) const;
unsigned getSizeExtEncoding(const MachineInstr &MI, unsigned OpNo) const;
unsigned getSizeInsEncoding(const MachineInstr &MI, unsigned OpNo) const;
void emitGlobalAddressUnaligned(const GlobalValue *GV, unsigned Reloc,
int Offset) const;
/// Expand pseudo instructions with accumulator register operands.
void expandACCInstr(MachineBasicBlock::instr_iterator MI,
MachineBasicBlock &MBB, unsigned Opc) const;
/// \brief Expand pseudo instruction. Return true if MI was expanded.
bool expandPseudos(MachineBasicBlock::instr_iterator &MI,
MachineBasicBlock &MBB) const;
};
}
char MipsCodeEmitter::ID = 0;
bool MipsCodeEmitter::runOnMachineFunction(MachineFunction &MF) {
MipsTargetMachine &Target = static_cast<MipsTargetMachine &>(
const_cast<TargetMachine &>(MF.getTarget()));
JTI = Target.getJITInfo();
II = Target.getInstrInfo();
TD = Target.getDataLayout();
Subtarget = &TM.getSubtarget<MipsSubtarget> ();
MCPEs = &MF.getConstantPool()->getConstants();
MJTEs = 0;
if (MF.getJumpTableInfo()) MJTEs = &MF.getJumpTableInfo()->getJumpTables();
JTI->Initialize(MF, IsPIC, Subtarget->isLittle());
MCE.setModuleInfo(&getAnalysis<MachineModuleInfo> ());
do {
DEBUG(errs() << "JITTing function '"
<< MF.getName() << "'\n");
MCE.startFunction(MF);
for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
MBB != E; ++MBB){
MCE.StartMachineBasicBlock(MBB);
for (MachineBasicBlock::instr_iterator I = MBB->instr_begin(),
E = MBB->instr_end(); I != E;)
emitInstruction(*I++, *MBB);
}
} while (MCE.finishFunction(MF));
return false;
}
unsigned MipsCodeEmitter::getRelocation(const MachineInstr &MI,
const MachineOperand &MO) const {
// NOTE: This relocations are for static.
uint64_t TSFlags = MI.getDesc().TSFlags;
uint64_t Form = TSFlags & MipsII::FormMask;
if (Form == MipsII::FrmJ)
return Mips::reloc_mips_26;
if ((Form == MipsII::FrmI || Form == MipsII::FrmFI)
&& MI.isBranch())
return Mips::reloc_mips_pc16;
if (Form == MipsII::FrmI && MI.getOpcode() == Mips::LUi)
return Mips::reloc_mips_hi;
return Mips::reloc_mips_lo;
}
unsigned MipsCodeEmitter::getJumpTargetOpValue(const MachineInstr &MI,
unsigned OpNo) const {
MachineOperand MO = MI.getOperand(OpNo);
if (MO.isGlobal())
emitGlobalAddress(MO.getGlobal(), getRelocation(MI, MO), true);
else if (MO.isSymbol())
emitExternalSymbolAddress(MO.getSymbolName(), getRelocation(MI, MO));
else if (MO.isMBB())
emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO));
else
llvm_unreachable("Unexpected jump target operand kind.");
return 0;
}
unsigned MipsCodeEmitter::getBranchTargetOpValue(const MachineInstr &MI,
unsigned OpNo) const {
MachineOperand MO = MI.getOperand(OpNo);
emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO));
return 0;
}
unsigned MipsCodeEmitter::getMemEncoding(const MachineInstr &MI,
unsigned OpNo) const {
// Base register is encoded in bits 20-16, offset is encoded in bits 15-0.
assert(MI.getOperand(OpNo).isReg());
unsigned RegBits = getMachineOpValue(MI, MI.getOperand(OpNo)) << 16;
return (getMachineOpValue(MI, MI.getOperand(OpNo+1)) & 0xFFFF) | RegBits;
}
unsigned MipsCodeEmitter::getSizeExtEncoding(const MachineInstr &MI,
unsigned OpNo) const {
// size is encoded as size-1.
return getMachineOpValue(MI, MI.getOperand(OpNo)) - 1;
}
unsigned MipsCodeEmitter::getSizeInsEncoding(const MachineInstr &MI,
unsigned OpNo) const {
// size is encoded as pos+size-1.
return getMachineOpValue(MI, MI.getOperand(OpNo-1)) +
getMachineOpValue(MI, MI.getOperand(OpNo)) - 1;
}
/// getMachineOpValue - Return binary encoding of operand. If the machine
/// operand requires relocation, record the relocation and return zero.
unsigned MipsCodeEmitter::getMachineOpValue(const MachineInstr &MI,
const MachineOperand &MO) const {
if (MO.isReg())
return TM.getRegisterInfo()->getEncodingValue(MO.getReg());
else if (MO.isImm())
return static_cast<unsigned>(MO.getImm());
else if (MO.isGlobal())
emitGlobalAddress(MO.getGlobal(), getRelocation(MI, MO), true);
else if (MO.isSymbol())
emitExternalSymbolAddress(MO.getSymbolName(), getRelocation(MI, MO));
else if (MO.isCPI())
emitConstPoolAddress(MO.getIndex(), getRelocation(MI, MO));
else if (MO.isJTI())
emitJumpTableAddress(MO.getIndex(), getRelocation(MI, MO));
else if (MO.isMBB())
emitMachineBasicBlock(MO.getMBB(), getRelocation(MI, MO));
else
llvm_unreachable("Unable to encode MachineOperand!");
return 0;
}
void MipsCodeEmitter::emitGlobalAddress(const GlobalValue *GV, unsigned Reloc,
bool MayNeedFarStub) const {
MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc,
const_cast<GlobalValue *>(GV), 0,
MayNeedFarStub));
}
void MipsCodeEmitter::emitGlobalAddressUnaligned(const GlobalValue *GV,
unsigned Reloc, int Offset) const {
MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc,
const_cast<GlobalValue *>(GV), 0, false));
MCE.addRelocation(MachineRelocation::getGV(MCE.getCurrentPCOffset() + Offset,
Reloc, const_cast<GlobalValue *>(GV), 0, false));
}
void MipsCodeEmitter::
emitExternalSymbolAddress(const char *ES, unsigned Reloc) const {
MCE.addRelocation(MachineRelocation::getExtSym(MCE.getCurrentPCOffset(),
Reloc, ES, 0, 0));
}
void MipsCodeEmitter::emitConstPoolAddress(unsigned CPI, unsigned Reloc) const {
MCE.addRelocation(MachineRelocation::getConstPool(MCE.getCurrentPCOffset(),
Reloc, CPI, 0, false));
}
void MipsCodeEmitter::
emitJumpTableAddress(unsigned JTIndex, unsigned Reloc) const {
MCE.addRelocation(MachineRelocation::getJumpTable(MCE.getCurrentPCOffset(),
Reloc, JTIndex, 0, false));
}
void MipsCodeEmitter::emitMachineBasicBlock(MachineBasicBlock *BB,
unsigned Reloc) const {
MCE.addRelocation(MachineRelocation::getBB(MCE.getCurrentPCOffset(),
Reloc, BB));
}
void MipsCodeEmitter::emitInstruction(MachineBasicBlock::instr_iterator MI,
MachineBasicBlock &MBB) {
DEBUG(errs() << "JIT: " << (void*)MCE.getCurrentPCValue() << ":\t" << *MI);
// Expand pseudo instruction. Skip if MI was not expanded.
if (((MI->getDesc().TSFlags & MipsII::FormMask) == MipsII::Pseudo) &&
!expandPseudos(MI, MBB))
return;
MCE.processDebugLoc(MI->getDebugLoc(), true);
emitWord(getBinaryCodeForInstr(*MI));
++NumEmitted; // Keep track of the # of mi's emitted
MCE.processDebugLoc(MI->getDebugLoc(), false);
}
void MipsCodeEmitter::emitWord(unsigned Word) {
DEBUG(errs() << " 0x";
errs().write_hex(Word) << "\n");
if (Subtarget->isLittle())
MCE.emitWordLE(Word);
else
MCE.emitWordBE(Word);
}
void MipsCodeEmitter::expandACCInstr(MachineBasicBlock::instr_iterator MI,
MachineBasicBlock &MBB,
unsigned Opc) const {
// Expand "pseudomult $ac0, $t0, $t1" to "mult $t0, $t1".
BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Opc))
.addReg(MI->getOperand(1).getReg()).addReg(MI->getOperand(2).getReg());
}
bool MipsCodeEmitter::expandPseudos(MachineBasicBlock::instr_iterator &MI,
MachineBasicBlock &MBB) const {
switch (MI->getOpcode()) {
case Mips::NOP:
BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Mips::SLL), Mips::ZERO)
.addReg(Mips::ZERO).addImm(0);
break;
case Mips::JALRPseudo:
BuildMI(MBB, &*MI, MI->getDebugLoc(), II->get(Mips::JALR), Mips::RA)
.addReg(MI->getOperand(0).getReg());
break;
case Mips::PseudoMULT:
expandACCInstr(MI, MBB, Mips::MULT);
break;
case Mips::PseudoMULTu:
expandACCInstr(MI, MBB, Mips::MULTu);
break;
case Mips::PseudoSDIV:
expandACCInstr(MI, MBB, Mips::SDIV);
break;
case Mips::PseudoUDIV:
expandACCInstr(MI, MBB, Mips::UDIV);
break;
case Mips::PseudoMADD:
expandACCInstr(MI, MBB, Mips::MADD);
break;
case Mips::PseudoMADDU:
expandACCInstr(MI, MBB, Mips::MADDU);
break;
case Mips::PseudoMSUB:
expandACCInstr(MI, MBB, Mips::MSUB);
break;
case Mips::PseudoMSUBU:
expandACCInstr(MI, MBB, Mips::MSUBU);
break;
default:
return false;
}
(MI--)->eraseFromBundle();
return true;
}
/// createMipsJITCodeEmitterPass - Return a pass that emits the collected Mips
/// code to the specified MCE object.
FunctionPass *llvm::createMipsJITCodeEmitterPass(MipsTargetMachine &TM,
JITCodeEmitter &JCE) {
return new MipsCodeEmitter(TM, JCE);
}
#include "MipsGenCodeEmitter.inc"
|