//===-- 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'.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "asm-printer"
#include "X86IntelAsmPrinter.h"
#include "X86TargetAsmInfo.h"
#include "X86.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Statistic.h"
using namespace llvm;
STATISTIC(EmittedInsts, "Number of machine instrs printed");
std::string X86IntelAsmPrinter::getSectionForFunction(const Function &F) const {
// Intel asm always emits functions to _text.
return "_text";
}
/// 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.
const Function *F = MF.getFunction();
unsigned CC = F->getCallingConv();
// Populate function information map. Actually, We don't want to populate
// non-stdcall or non-fastcall functions' information right now.
if (CC == CallingConv::X86_StdCall || CC == CallingConv::X86_FastCall)
FunctionInfoMap[F] = *MF.getInfo<X86MachineFunctionInfo>();
X86SharedAsmPrinter::decorateName(CurrentFnName, F);
SwitchToTextSection(getSectionForFunction(*F).c_str(), F);
switch (F->getLinkage()) {
default: assert(0 && "Unsupported linkage type!");
case Function::InternalLinkage:
EmitAlignment(4);
break;
case Function::DLLExportLinkage:
DLLExportedFns.insert(CurrentFnName);
//FALLS THROUGH
case Function::ExternalLinkage:
O << "\tpublic " << CurrentFnName << "\n";
EmitAlignment(4);
break;
}
O << CurrentFnName << "\tproc near\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()) {
printBasicBlockLabel(I, true);
O << '\n';
}
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
O << "\t";
printMachineInstruction(II);
}
}
// Print out jump tables referenced by the function.
EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
O << CurrentFnName << "\tendp\n";
// 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,
const char *Modifier) {
const MRegisterInfo &RI = *TM.getRegisterInfo();
switch (MO.getType()) {
case MachineOperand::MO_Register: {
if (MRegisterInfo::isPhysicalRegister(MO.getReg())) {
unsigned Reg = MO.getReg();
if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
MVT::ValueType VT = (strcmp(Modifier,"subreg64") == 0) ?
MVT::i64 : ((strcmp(Modifier, "subreg32") == 0) ? MVT::i32 :
((strcmp(Modifier,"subreg16") == 0) ? MVT::i16 :MVT::i8));
Reg = getX86SubSuperRegister(Reg, VT);
}
O << RI.get(Reg).Name;
} else
O << "reg" << MO.getReg();
return;
}
case MachineOperand::MO_Immediate:
O << MO.getImmedValue();
return;
case MachineOperand::MO_MachineBasicBlock:
printBasicBlockLabel(MO.getMachineBasicBlock());
return;
case MachineOperand::MO_JumpTableIndex: {
bool isMemOp = Modifier && !strcmp(Modifier, "mem");
if (!isMemOp) O << "OFFSET ";
O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
<< "_" << MO.getJumpTableIndex();
return;
}
case MachineOperand::MO_ConstantPoolIndex: {
bool isMemOp = Modifier && !strcmp(Modifier, "mem");
if (!isMemOp) O << "OFFSET ";
O << "[" << TAI->getPrivateGlobalPrefix() << "CPI"
<< getFunctionNumber() << "_" << MO.getConstantPoolIndex();
int Offset = MO.getOffset();
if (Offset > 0)
O << " + " << Offset;
else if (Offset < 0)
O << Offset;
O << "]";
return;
}
case MachineOperand::MO_GlobalAddress: {
bool isCallOp = Modifier && !strcmp(Modifier, "call");
bool isMemOp = Modifier && !strcmp(Modifier, "mem");
GlobalValue *GV = MO.getGlobal();
std::string Name = Mang->getValueName(GV);
X86SharedAsmPrinter::decorateName(Name, GV);
if (!isMemOp && !isCallOp) O << "OFFSET ";
if (GV->hasDLLImportLinkage()) {
// FIXME: This should be fixed with full support of stdcall & fastcall
// CC's
O << "__imp_";
}
O << Name;
int Offset = MO.getOffset();
if (Offset > 0)
O << " + " << Offset;
else if (Offset < 0)
O << Offset;
return;
}
case MachineOperand::MO_ExternalSymbol: {
bool isCallOp = Modifier && !strcmp(Modifier, "call");
if (!isCallOp) O << "OFFSET ";
O << TAI->getGlobalPrefix() << MO.getSymbolName();
return;
}
default:
O << "<unknown operand type>"; return;
}
}
void X86IntelAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
const char *Modifier) {
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);
O << "[";
bool NeedPlus = false;
if (BaseReg.getReg()) {
printOp(BaseReg, Modifier);
NeedPlus = true;
}
if (IndexReg.getReg()) {
if (NeedPlus) O << " + ";
if (ScaleVal != 1)
O << ScaleVal << "*";
printOp(IndexReg, Modifier);
NeedPlus = true;
}
if (DispSpec.isGlobalAddress() || DispSpec.isConstantPoolIndex() ||
DispSpec.isJumpTableIndex()) {
if (NeedPlus)
O << " + ";
printOp(DispSpec, "mem");
} else {
int DispVal = DispSpec.getImmedValue();
if (DispVal || (!BaseReg.getReg() && !IndexReg.getReg())) {
if (NeedPlus)
if (DispVal > 0)
O << " + ";
else {
O << " - ";
DispVal = -DispVal;
}
O << DispVal;
}
}
O << "]";
}
void X86IntelAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
O << "\"L" << getFunctionNumber() << "$pb\"\n";
O << "\"L" << getFunctionNumber() << "$pb\":";
}
bool X86IntelAsmPrinter::printAsmMRegister(const MachineOperand &MO,
const char Mode) {
const MRegisterInfo &RI = *TM.getRegisterInfo();
unsigned Reg = MO.getReg();
switch (Mode) {
default: return true; // Unknown mode.
case 'b': // Print QImode register
Reg = getX86SubSuperRegister(Reg, MVT::i8);
break;
case 'h': // Print QImode high register
Reg = getX86SubSuperRegister(Reg, MVT::i8, true);
break;
case 'w': // Print HImode register
Reg = getX86SubSuperRegister(Reg, MVT::i16);
break;
case 'k': // Print SImode register
Reg = getX86SubSuperRegister(Reg, MVT::i32);
break;
}
O << '%' << RI.get(Reg).Name;
return false;
}
/// PrintAsmOperand - Print out an operand for an inline asm expression.
///
bool X86IntelAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode) {
// Does this asm operand have a single letter operand modifier?
if (ExtraCode && ExtraCode[0]) {
if (ExtraCode[1] != 0) return true; // Unknown modifier.
switch (ExtraCode[0]) {
default: return true; // Unknown modifier.
case 'b': // Print QImode register
case 'h': // Print QImode high register
case 'w': // Print HImode register
case 'k': // Print SImode register
return printAsmMRegister(MI->getOperand(OpNo), ExtraCode[0]);
}
}
printOperand(MI, OpNo);
return false;
}
bool X86IntelAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI,
unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode) {
if (ExtraCode && ExtraCode[0])
return true; // Unknown modifier.
printMemReference(MI, OpNo);
return false;
}
/// printMachineInstruction -- Print out a single X86 LLVM instruction
/// MI in Intel syntax to the current output stream.
///
void X86IntelAsmPrinter::printMachineInstruction(const MachineInstr *MI) {
++EmittedInsts;
// See if a truncate instruction can be turned into a nop.
switch (MI->getOpcode()) {
default: break;
case X86::PsMOVZX64rr32:
O << TAI->getCommentString() << " ZERO-EXTEND " << "\n\t";
break;
}
// Call the autogenerated instruction printer routines.
printInstruction(MI);
}
bool X86IntelAsmPrinter::doInitialization(Module &M) {
bool Result = X86SharedAsmPrinter::doInitialization(M);
Mang->markCharUnacceptable('.');
O << "\t.686\n\t.model flat\n\n";
// Emit declarations for external functions.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (I->isDeclaration()) {
std::string Name = Mang->getValueName(I);
X86SharedAsmPrinter::decorateName(Name, I);
O << "\textern " ;
if (I->hasDLLImportLinkage()) {
O << "__imp_";
}
O << Name << ":near\n";
}
// Emit declarations for external globals. Note that VC++ always declares
// external globals to have type byte, and if that's good enough for VC++...
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
if (I->isDeclaration()) {
std::string Name = Mang->getValueName(I);
O << "\textern " ;
if (I->hasDLLImportLinkage()) {
O << "__imp_";
}
O << Name << ":byte\n";
}
}
return Result;
}
bool X86IntelAsmPrinter::doFinalization(Module &M) {
const TargetData *TD = TM.getTargetData();
// Print out module-level global variables here.
for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
if (I->isDeclaration()) continue; // External global require no code
// Check to see if this is a special global used by LLVM, if so, emit it.
if (EmitSpecialLLVMGlobal(I))
continue;
std::string name = Mang->getValueName(I);
Constant *C = I->getInitializer();
unsigned Align = TD->getPreferredAlignmentLog(I);
bool bCustomSegment = false;
switch (I->getLinkage()) {
case GlobalValue::LinkOnceLinkage:
case GlobalValue::WeakLinkage:
SwitchToDataSection("");
O << name << "?\tsegment common 'COMMON'\n";
bCustomSegment = true;
// FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256
// are also available.
break;
case GlobalValue::AppendingLinkage:
SwitchToDataSection("");
O << name << "?\tsegment public 'DATA'\n";
bCustomSegment = true;
// FIXME: the default alignment is 16 bytes, but 1, 2, 4, and 256
// are also available.
break;
case GlobalValue::DLLExportLinkage:
DLLExportedGVs.insert(name);
// FALL THROUGH
case GlobalValue::ExternalLinkage:
O << "\tpublic " << name << "\n";
// FALL THROUGH
case GlobalValue::InternalLinkage:
SwitchToDataSection(TAI->getDataSection(), I);
break;
default:
assert(0 && "Unknown linkage type!");
}
if (!bCustomSegment)
EmitAlignment(Align, I);
O << name << ":\t\t\t\t" << TAI->getCommentString()
<< " " << I->getName() << '\n';
EmitGlobalConstant(C);
if (bCustomSegment)
O << name << "?\tends\n";
}
// Output linker support code for dllexported globals
if ((DLLExportedGVs.begin() != DLLExportedGVs.end()) ||
(DLLExportedFns.begin() != DLLExportedFns.end())) {
SwitchToDataSection("");
O << "; WARNING: The following code is valid only with MASM v8.x and (possible) higher\n"
<< "; This version of MASM is usually shipped with Microsoft Visual Studio 2005\n"
<< "; or (possible) further versions. Unfortunately, there is no way to support\n"
<< "; dllexported symbols in the earlier versions of MASM in fully automatic way\n\n";
O << "_drectve\t segment info alias('.drectve')\n";
}
for (std::set<std::string>::iterator i = DLLExportedGVs.begin(),
e = DLLExportedGVs.end();
i != e; ++i) {
O << "\t db ' /EXPORT:" << *i << ",data'\n";
}
for (std::set<std::string>::iterator i = DLLExportedFns.begin(),
e = DLLExportedFns.end();
i != e; ++i) {
O << "\t db ' /EXPORT:" << *i << "'\n";
}
if ((DLLExportedGVs.begin() != DLLExportedGVs.end()) ||
(DLLExportedFns.begin() != DLLExportedFns.end())) {
O << "_drectve\t ends\n";
}
// Bypass X86SharedAsmPrinter::doFinalization().
bool Result = AsmPrinter::doFinalization(M);
SwitchToDataSection("");
O << "\tend\n";
return Result;
}
void X86IntelAsmPrinter::EmitString(const ConstantArray *CVA) const {
unsigned NumElts = CVA->getNumOperands();
if (NumElts) {
// ML does not have escape sequences except '' for '. It also has a maximum
// string length of 255.
unsigned len = 0;
bool inString = false;
for (unsigned i = 0; i < NumElts; i++) {
int n = cast<ConstantInt>(CVA->getOperand(i))->getZExtValue() & 255;
if (len == 0)
O << "\tdb ";
if (n >= 32 && n <= 127) {
if (!inString) {
if (len > 0) {
O << ",'";
len += 2;
} else {
O << "'";
len++;
}
inString = true;
}
if (n == '\'') {
O << "'";
len++;
}
O << char(n);
} else {
if (inString) {
O << "'";
len++;
inString = false;
}
if (len > 0) {
O << ",";
len++;
}
O << n;
len += 1 + (n > 9) + (n > 99);
}
if (len > 60) {
if (inString) {
O << "'";
inString = false;
}
O << "\n";
len = 0;
}
}
if (len > 0) {
if (inString)
O << "'";
O << "\n";
}
}
}
// Include the auto-generated portion of the assembly writer.
#include "X86GenAsmWriter1.inc"
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