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//===-- X86IntelAsmPrinter.cpp - Convert X86 LLVM code to Intel assembly --===//
//
// The LLVM Compiler Infrastructure
//
// This file 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 "X86InstrInfo.h"
#include "X86TargetAsmInfo.h"
#include "X86.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/CodeGen/DwarfWriter.h"
#include "llvm/Support/Mangler.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;
STATISTIC(EmittedInsts, "Number of machine instrs printed");
static X86MachineFunctionInfo calculateFunctionInfo(const Function *F,
const TargetData *TD) {
X86MachineFunctionInfo Info;
uint64_t Size = 0;
switch (F->getCallingConv()) {
case CallingConv::X86_StdCall:
Info.setDecorationStyle(StdCall);
break;
case CallingConv::X86_FastCall:
Info.setDecorationStyle(FastCall);
break;
default:
return Info;
}
unsigned argNum = 1;
for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
AI != AE; ++AI, ++argNum) {
const Type* Ty = AI->getType();
// 'Dereference' type in case of byval parameter attribute
if (F->paramHasAttr(argNum, Attribute::ByVal))
Ty = cast<PointerType>(Ty)->getElementType();
// Size should be aligned to DWORD boundary
Size += ((TD->getTypePaddedSize(Ty) + 3)/4)*4;
}
// We're not supporting tooooo huge arguments :)
Info.setBytesToPopOnReturn((unsigned int)Size);
return Info;
}
/// decorateName - Query FunctionInfoMap and use this information for various
/// name decoration.
void X86IntelAsmPrinter::decorateName(std::string &Name,
const GlobalValue *GV) {
const Function *F = dyn_cast<Function>(GV);
if (!F) return;
// We don't want to decorate non-stdcall or non-fastcall functions right now
unsigned CC = F->getCallingConv();
if (CC != CallingConv::X86_StdCall && CC != CallingConv::X86_FastCall)
return;
FMFInfoMap::const_iterator info_item = FunctionInfoMap.find(F);
const X86MachineFunctionInfo *Info;
if (info_item == FunctionInfoMap.end()) {
// Calculate apropriate function info and populate map
FunctionInfoMap[F] = calculateFunctionInfo(F, TM.getTargetData());
Info = &FunctionInfoMap[F];
} else {
Info = &info_item->second;
}
const FunctionType *FT = F->getFunctionType();
switch (Info->getDecorationStyle()) {
case None:
break;
case StdCall:
// "Pure" variadic functions do not receive @0 suffix.
if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
(FT->getNumParams() == 1 && F->hasStructRetAttr()))
Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
break;
case FastCall:
// "Pure" variadic functions do not receive @0 suffix.
if (!FT->isVarArg() || (FT->getNumParams() == 0) ||
(FT->getNumParams() == 1 && F->hasStructRetAttr()))
Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
if (Name[0] == '_')
Name[0] = '@';
else
Name = '@' + Name;
break;
default:
assert(0 && "Unsupported DecorationStyle");
}
}
/// runOnMachineFunction - This uses the printMachineInstruction()
/// method to print assembly for each instruction.
///
bool X86IntelAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
this->MF = &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>();
decorateName(CurrentFnName, F);
SwitchToTextSection("_text", F);
unsigned FnAlign = 4;
if (F->hasFnAttr(Attribute::OptimizeForSize))
FnAlign = 1;
switch (F->getLinkage()) {
default: assert(0 && "Unsupported linkage type!");
case Function::PrivateLinkage:
case Function::InternalLinkage:
EmitAlignment(FnAlign);
break;
case Function::DLLExportLinkage:
DLLExportedFns.insert(CurrentFnName);
//FALLS THROUGH
case Function::ExternalLinkage:
O << "\tpublic " << CurrentFnName << "\n";
EmitAlignment(FnAlign);
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_empty()) {
printBasicBlockLabel(I, true, true);
O << '\n';
}
for (MachineBasicBlock::const_iterator II = I->begin(), E = I->end();
II != E; ++II) {
// Print the assembly for the instruction.
printMachineInstruction(II);
}
}
// Print out jump tables referenced by the function.
EmitJumpTableInfo(MF.getJumpTableInfo(), MF);
O << CurrentFnName << "\tendp\n";
O.flush();
// We didn't modify anything.
return false;
}
void X86IntelAsmPrinter::printSSECC(const MachineInstr *MI, unsigned Op) {
unsigned char value = MI->getOperand(Op).getImm();
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) {
switch (MO.getType()) {
case MachineOperand::MO_Register: {
if (TargetRegisterInfo::isPhysicalRegister(MO.getReg())) {
unsigned Reg = MO.getReg();
if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
MVT 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 << TRI->getName(Reg);
} else
O << "reg" << MO.getReg();
return;
}
case MachineOperand::MO_Immediate:
O << MO.getImm();
return;
case MachineOperand::MO_MachineBasicBlock:
printBasicBlockLabel(MO.getMBB());
return;
case MachineOperand::MO_JumpTableIndex: {
bool isMemOp = Modifier && !strcmp(Modifier, "mem");
if (!isMemOp) O << "OFFSET ";
O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
<< "_" << MO.getIndex();
return;
}
case MachineOperand::MO_ConstantPoolIndex: {
bool isMemOp = Modifier && !strcmp(Modifier, "mem");
if (!isMemOp) O << "OFFSET ";
O << "[" << TAI->getPrivateGlobalPrefix() << "CPI"
<< getFunctionNumber() << "_" << MO.getIndex();
printOffset(MO.getOffset());
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);
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;
printOffset(MO.getOffset());
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::printLeaMemReference(const MachineInstr *MI,
unsigned Op,
const char *Modifier) {
const MachineOperand &BaseReg = MI->getOperand(Op);
int ScaleVal = MI->getOperand(Op+1).getImm();
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.isGlobal() || DispSpec.isCPI() ||
DispSpec.isJTI()) {
if (NeedPlus)
O << " + ";
printOp(DispSpec, "mem");
} else {
int DispVal = DispSpec.getImm();
if (DispVal || (!BaseReg.getReg() && !IndexReg.getReg())) {
if (NeedPlus) {
if (DispVal > 0)
O << " + ";
else {
O << " - ";
DispVal = -DispVal;
}
}
O << DispVal;
}
}
O << "]";
}
void X86IntelAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
const char *Modifier) {
assert(isMem(MI, Op) && "Invalid memory reference!");
MachineOperand Segment = MI->getOperand(Op+4);
if (Segment.getReg()) {
printOperand(MI, Op+4, Modifier);
O << ':';
}
printLeaMemReference(MI, Op, Modifier);
}
void X86IntelAsmPrinter::printPICJumpTableSetLabel(unsigned uid,
const MachineBasicBlock *MBB) const {
if (!TAI->getSetDirective())
return;
O << TAI->getSetDirective() << ' ' << TAI->getPrivateGlobalPrefix()
<< getFunctionNumber() << '_' << uid << "_set_" << MBB->getNumber() << ',';
printBasicBlockLabel(MBB, false, false, false);
O << '-' << "\"L" << getFunctionNumber() << "$pb\"'\n";
}
void X86IntelAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
O << "\"L" << getFunctionNumber() << "$pb\"\n";
O << "\"L" << getFunctionNumber() << "$pb\":";
}
bool X86IntelAsmPrinter::printAsmMRegister(const MachineOperand &MO,
const char Mode) {
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 << '%' << TRI->getName(Reg);
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;
// Call the autogenerated instruction printer routines.
printInstruction(MI);
}
bool X86IntelAsmPrinter::doInitialization(Module &M) {
bool Result = AsmPrinter::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);
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::CommonLinkage:
case GlobalValue::LinkOnceAnyLinkage:
case GlobalValue::LinkOnceODRLinkage:
case GlobalValue::WeakAnyLinkage:
case GlobalValue::WeakODRLinkage:
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:
SwitchToSection(TAI->getDataSection());
break;
default:
assert(0 && "Unknown linkage type!");
}
if (!bCustomSegment)
EmitAlignment(Align, I);
O << name << ":";
if (VerboseAsm)
O << "\t\t\t\t" << TAI->getCommentString()
<< " " << I->getName();
O << '\n';
EmitGlobalConstant(C);
if (bCustomSegment)
O << name << "?\tends\n";
}
// Output linker support code for dllexported globals
if (!DLLExportedGVs.empty() || !DLLExportedFns.empty()) {
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 (StringSet<>::iterator i = DLLExportedGVs.begin(),
e = DLLExportedGVs.end();
i != e; ++i)
O << "\t db ' /EXPORT:" << i->getKeyData() << ",data'\n";
for (StringSet<>::iterator i = DLLExportedFns.begin(),
e = DLLExportedFns.end();
i != e; ++i)
O << "\t db ' /EXPORT:" << i->getKeyData() << "'\n";
if (!DLLExportedGVs.empty() || !DLLExportedFns.empty())
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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