llvm-6502/lib/Target/X86/X86IntelAsmPrinter.cpp

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//===-- X86IntelAsmPrinter.cpp - Convert X86 LLVM code to Intel assembly --===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains a printer that converts from our internal representation
// of machine-dependent LLVM code to Intel format assembly language.
// This printer is the output mechanism used by `llc'.
//
//===----------------------------------------------------------------------===//
#include "X86IntelAsmPrinter.h"
#include "X86.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/Mangler.h"
using namespace llvm;
using namespace x86;
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool X86IntelAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
SetupMachineFunction(MF);
O << "\n\n";
// Print out constants referenced by the function
EmitConstantPool(MF.getConstantPool());
// Print out labels for the function.
SwitchSection("\t.text\n", MF.getFunction());
EmitAlignment(4);
O << "\t.globl\t" << CurrentFnName << "\n";
if (HasDotTypeDotSizeDirective)
O << "\t.type\t" << CurrentFnName << ", @function\n";
O << CurrentFnName << ":\n";
// Print out code for the function.
for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
I != E; ++I) {
// Print a label for the basic block if there are any predecessors.
if (I->pred_begin() != I->pred_end())
O << PrivateGlobalPrefix << "BB" << CurrentFnName << "_" << I->getNumber()
<< ":\t"
<< CommentString << " " << I->getBasicBlock()->getName() << "\n";
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
O << "\t";
printMachineInstruction(II);
}
}
// We didn't modify anything.
return false;
}
void X86IntelAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
unsigned char value = MI->getOperand(Op).getImmedValue();
assert(value <= 7 && "Invalid ssecc argument!");
switch (value) {
case 0: O << "eq"; break;
case 1: O << "lt"; break;
case 2: O << "le"; break;
case 3: O << "unord"; break;
case 4: O << "neq"; break;
case 5: O << "nlt"; break;
case 6: O << "nle"; break;
case 7: O << "ord"; break;
}
}
void X86IntelAsmPrinter::printOp(const MachineOperand &MO,
bool elideOffsetKeyword /* = false */) {
const MRegisterInfo &RI = *TM.getRegisterInfo();
switch (MO.getType()) {
case MachineOperand::MO_VirtualRegister:
if (Value *V = MO.getVRegValueOrNull()) {
O << "<" << V->getName() << ">";
return;
}
// FALLTHROUGH
case MachineOperand::MO_MachineRegister:
if (MRegisterInfo::isPhysicalRegister(MO.getReg()))
// Bug Workaround: See note in Printer::doInitialization about %.
O << "%" << RI.get(MO.getReg()).Name;
else
O << "%reg" << MO.getReg();
return;
case MachineOperand::MO_SignExtendedImmed:
case MachineOperand::MO_UnextendedImmed:
O << (int)MO.getImmedValue();
return;
case MachineOperand::MO_MachineBasicBlock: {
MachineBasicBlock *MBBOp = MO.getMachineBasicBlock();
O << PrivateGlobalPrefix << "BB"
<< Mang->getValueName(MBBOp->getParent()->getFunction())
<< "_" << MBBOp->getNumber () << "\t# "
<< MBBOp->getBasicBlock ()->getName ();
return;
}
case MachineOperand::MO_PCRelativeDisp:
assert(0 && "Shouldn't use addPCDisp() when building X86 MachineInstrs");
abort ();
return;
case MachineOperand::MO_GlobalAddress: {
if (!elideOffsetKeyword)
O << "OFFSET ";
O << Mang->getValueName(MO.getGlobal());
int Offset = MO.getOffset();
if (Offset > 0)
O << " + " << Offset;
else if (Offset < 0)
O << Offset;
return;
}
case MachineOperand::MO_ExternalSymbol:
O << GlobalPrefix << MO.getSymbolName();
return;
default:
O << "<unknown operand type>"; return;
}
}
void X86IntelAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op){
assert(isMem(MI, Op) && "Invalid memory reference!");
const MachineOperand &BaseReg = MI->getOperand(Op);
int ScaleVal = MI->getOperand(Op+1).getImmedValue();
const MachineOperand &IndexReg = MI->getOperand(Op+2);
const MachineOperand &DispSpec = MI->getOperand(Op+3);
if (BaseReg.isFrameIndex()) {
O << "[frame slot #" << BaseReg.getFrameIndex();
if (DispSpec.getImmedValue())
O << " + " << DispSpec.getImmedValue();
O << "]";
return;
} else if (BaseReg.isConstantPoolIndex()) {
O << "[" << PrivateGlobalPrefix << "CPI" << getFunctionNumber() << "_"
<< BaseReg.getConstantPoolIndex();
if (IndexReg.getReg()) {
O << " + ";
if (ScaleVal != 1)
O << ScaleVal << "*";
printOp(IndexReg);
}
if (DispSpec.getImmedValue())
O << " + " << DispSpec.getImmedValue();
O << "]";
return;
}
O << "[";
bool NeedPlus = false;
if (BaseReg.getReg()) {
printOp(BaseReg, true);
NeedPlus = true;
}
if (IndexReg.getReg()) {
if (NeedPlus) O << " + ";
if (ScaleVal != 1)
O << ScaleVal << "*";
printOp(IndexReg);
NeedPlus = true;
}
if (DispSpec.isGlobalAddress()) {
if (NeedPlus)
O << " + ";
printOp(DispSpec, true);
} else {
int DispVal = DispSpec.getImmedValue();
if (DispVal || (!BaseReg.getReg() && !IndexReg.getReg())) {
if (NeedPlus)
if (DispVal > 0)
O << " + ";
else {
O << " - ";
DispVal = -DispVal;
}
O << DispVal;
}
}
O << "]";
}
/// printMachineInstruction -- Print out a single X86 LLVM instruction
/// MI in Intel syntax to the current output stream.
///
void X86IntelAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
++EmittedInsts;
// Call the autogenerated instruction printer routines.
printInstruction(MI);
}
bool X86IntelAsmPrinter::doInitialization(Module &M) {
X86SharedAsmPrinter::doInitialization(M);
// Tell gas we are outputting Intel syntax (not AT&T syntax) assembly.
//
// Bug: gas in `intel_syntax noprefix' mode interprets the symbol `Sp' in an
// instruction as a reference to the register named sp, and if you try to
// reference a symbol `Sp' (e.g. `mov ECX, OFFSET Sp') then it gets lowercased
// before being looked up in the symbol table. This creates spurious
// `undefined symbol' errors when linking. Workaround: Do not use `noprefix'
// mode, and decorate all register names with percent signs.
O << "\t.intel_syntax\n";
return false;
}
// Include the auto-generated portion of the assembly writer.
#include "X86GenAsmWriter1.inc"