llvm/lib/Target/X86/X86ATTAsmPrinter.cpp - toolchain/llvm-project - Gitiles

 //===-- X86ATTAsmPrinter.cpp - Convert X86 LLVM code to AT&T 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 AT&T format assembly
 // language. This printer is the output mechanism used by `llc'.
 //
 //===----------------------------------------------------------------------===//

 #define DEBUG_TYPE "asm-printer"
 #include "X86ATTAsmPrinter.h"
 #include "X86.h"
 #include "X86COFF.h"
 #include "X86MachineFunctionInfo.h"
 #include "X86TargetMachine.h"
 #include "X86TargetAsmInfo.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/CallingConv.h"
 #include "llvm/Module.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");

 static std::string computePICLabel(unsigned FnNum,
                                    const TargetAsmInfo *TAI,
                                    const X86Subtarget* Subtarget)  {
   std::string label;
   if (Subtarget->isTargetDarwin())
     label =  "\"L" + utostr_32(FnNum) + "$pb\"";
   else if (Subtarget->isTargetELF())
     label = ".Lllvm$" + utostr_32(FnNum) + "$piclabel";
   else
     assert(0 && "Don't know how to print PIC label!\n");

   return label;
 }

 /// getSectionForFunction - Return the section that we should emit the
 /// specified function body into.
 std::string X86ATTAsmPrinter::getSectionForFunction(const Function &F) const {
   switch (F.getLinkage()) {
   default: assert(0 && "Unknown linkage type!");
   case Function::InternalLinkage:
   case Function::DLLExportLinkage:
   case Function::ExternalLinkage:
     return TAI->getTextSection();
   case Function::WeakLinkage:
   case Function::LinkOnceLinkage:
     if (Subtarget->isTargetDarwin()) {
       return ".section __TEXT,__textcoal_nt,coalesced,pure_instructions";
     } else if (Subtarget->isTargetCygMing()) {
       return "\t.section\t.text$linkonce." + CurrentFnName + ",\"ax\"";
     } else {
       return "\t.section\t.llvm.linkonce.t." + CurrentFnName +
              ",\"ax\",@progbits";
     }
   }
 }

 /// runOnMachineFunction - This uses the printMachineInstruction()
 /// method to print assembly for each instruction.
 ///
 bool X86ATTAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
   if (TAI->doesSupportDebugInformation()) {
     // Let PassManager know we need debug information and relay
     // the MachineModuleInfo address on to DwarfWriter.
     MMI = &getAnalysis<MachineModuleInfo>();
     DW.SetModuleInfo(MMI);
   }

   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 && "Unknown linkage type!");
   case Function::InternalLinkage:  // Symbols default to internal.
     if (Subtarget->isTargetDarwin())
       // FIXME: This should be parameterized somewhere.
       EmitAlignment(4, F, 0, true, 0x90);
     else
       EmitAlignment(4, F);     // FIXME: This should be parameterized somewhere.
     break;
   case Function::DLLExportLinkage:
     DLLExportedFns.insert(Mang->makeNameProper(F->getName(), ""));
     //FALLS THROUGH
   case Function::ExternalLinkage:
     if (Subtarget->isTargetDarwin())
       // FIXME: This should be parameterized somewhere.
       EmitAlignment(4, F, 0, true, 0x90);
     else
       EmitAlignment(4, F);     // FIXME: This should be parameterized somewhere.
     O << "\t.globl\t" << CurrentFnName << "\n";
     break;
   case Function::LinkOnceLinkage:
   case Function::WeakLinkage:
     if (Subtarget->isTargetDarwin()) {
       // FIXME: This should be parameterized somewhere.
       EmitAlignment(4, F, 0, true, 0x90);
       O << "\t.globl\t" << CurrentFnName << "\n";
       O << "\t.weak_definition\t" << CurrentFnName << "\n";
     } else if (Subtarget->isTargetCygMing()) {
       EmitAlignment(4, F);     // FIXME: This should be parameterized somewhere.
       O << "\t.globl\t" << CurrentFnName << "\n";
       O << "\t.linkonce discard\n";
     } else {
       EmitAlignment(4, F);     // FIXME: This should be parameterized somewhere.
       O << "\t.weak\t" << CurrentFnName << "\n";
     }
     break;
   }
   if (F->hasHiddenVisibility()) {
     if (const char *Directive = TAI->getHiddenDirective())
       O << Directive << CurrentFnName << "\n";
   } else if (F->hasProtectedVisibility()) {
     if (const char *Directive = TAI->getProtectedDirective())
       O << Directive << CurrentFnName << "\n";
   }

   if (Subtarget->isTargetELF())
     O << "\t.type\t" << CurrentFnName << ",@function\n";
   else if (Subtarget->isTargetCygMing()) {
     O << "\t.def\t " << CurrentFnName
       << ";\t.scl\t" <<
       (F->getLinkage() == Function::InternalLinkage ? COFF::C_STAT : COFF::C_EXT)
       << ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
       << ";\t.endef\n";
   }

   O << CurrentFnName << ":\n";
   // Add some workaround for linkonce linkage on Cygwin\MinGW
   if (Subtarget->isTargetCygMing() &&
       (F->getLinkage() == Function::LinkOnceLinkage ||
        F->getLinkage() == Function::WeakLinkage))
     O << "Lllvm$workaround$fake$stub$" << CurrentFnName << ":\n";

   if (TAI->doesSupportDebugInformation()) {
     // Emit pre-function debug information.
     DW.BeginFunction(&MF);
   }

   // 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 (!I->pred_empty()) {
       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);
     }
   }

   if (TAI->hasDotTypeDotSizeDirective())
     O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << "\n";

   if (TAI->doesSupportDebugInformation()) {
     // Emit post-function debug information.
     DW.EndFunction();
   }

   // Print out jump tables referenced by the function.
   EmitJumpTableInfo(MF.getJumpTableInfo(), MF);

   // We didn't modify anything.
   return false;
 }

 static inline bool printGOT(TargetMachine &TM, const X86Subtarget* ST) {
   return ST->isPICStyleGOT() && TM.getRelocationModel() == Reloc::PIC_;
 }

 static inline bool printStub(TargetMachine &TM, const X86Subtarget* ST) {
   return ST->isPICStyleStub() && TM.getRelocationModel() != Reloc::Static;
 }

 void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
                                     const char *Modifier, bool NotRIPRel) {
   const MachineOperand &MO = MI->getOperand(OpNo);
   const MRegisterInfo &RI = *TM.getRegisterInfo();
   switch (MO.getType()) {
   case MachineOperand::MO_Register: {
     assert(MRegisterInfo::isPhysicalRegister(MO.getReg()) &&
            "Virtual registers should not make it this far!");
     O << '%';
     unsigned Reg = MO.getReg();
     if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
       MVT::ValueType VT = (strcmp(Modifier+6,"64") == 0) ?
         MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
                     ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
       Reg = getX86SubSuperRegister(Reg, VT);
     }
     for (const char *Name = RI.get(Reg).Name; *Name; ++Name)
       O << (char)tolower(*Name);
     return;
   }

   case MachineOperand::MO_Immediate:
     if (!Modifier ||
         (strcmp(Modifier, "debug") && strcmp(Modifier, "mem")))
       O << '$';
     O << MO.getImmedValue();
     return;
   case MachineOperand::MO_MachineBasicBlock:
     printBasicBlockLabel(MO.getMachineBasicBlock());
     return;
   case MachineOperand::MO_JumpTableIndex: {
     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
     if (!isMemOp) O << '$';
     O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << "_"
       << MO.getJumpTableIndex();

     if (TM.getRelocationModel() == Reloc::PIC_) {
       if (Subtarget->isPICStyleStub())
         O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
           << "$pb\"";
       else if (Subtarget->isPICStyleGOT())
         O << "@GOTOFF";
     }

     if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
       O << "(%rip)";
     return;
   }
   case MachineOperand::MO_ConstantPoolIndex: {
     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
     if (!isMemOp) O << '$';
     O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << "_"
       << MO.getConstantPoolIndex();

     if (TM.getRelocationModel() == Reloc::PIC_) {
       if (Subtarget->isPICStyleStub())
         O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
           << "$pb\"";
       else if (Subtarget->isPICStyleGOT())
         O << "@GOTOFF";
     }

     int Offset = MO.getOffset();
     if (Offset > 0)
       O << "+" << Offset;
     else if (Offset < 0)
       O << Offset;

     if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
       O << "(%rip)";
     return;
   }
   case MachineOperand::MO_GlobalAddress: {
     bool isCallOp = Modifier && !strcmp(Modifier, "call");
     bool isMemOp  = Modifier && !strcmp(Modifier, "mem");
     bool needCloseParen = false;

     GlobalValue *GV = MO.getGlobal();
     GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
     bool isThreadLocal = GVar && GVar->isThreadLocal();

     std::string Name = Mang->getValueName(GV);
     X86SharedAsmPrinter::decorateName(Name, GV);

     if (!isMemOp && !isCallOp)
       O << '$';
     else if (Name[0] == '$') {
       // The name begins with a dollar-sign. In order to avoid having it look
       // like an integer immediate to the assembler, enclose it in parens.
       O << '(';
       needCloseParen = true;
     }

     if (printStub(TM, Subtarget)) {
       // Link-once, declaration, or Weakly-linked global variables need
       // non-lazily-resolved stubs
       if (GV->isDeclaration() ||
           GV->hasWeakLinkage() ||
           GV->hasLinkOnceLinkage()) {
         // Dynamically-resolved functions need a stub for the function.
         if (isCallOp && isa<Function>(GV)) {
           FnStubs.insert(Name);
           O << TAI->getPrivateGlobalPrefix() << Name << "$stub";
         } else {
           GVStubs.insert(Name);
           O << TAI->getPrivateGlobalPrefix() << Name << "$non_lazy_ptr";
         }
       } else {
         if (GV->hasDLLImportLinkage())
           O << "__imp_";
         O << Name;
       }

       if (!isCallOp && TM.getRelocationModel() == Reloc::PIC_)
         O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
           << "$pb\"";
     } else {
       if (GV->hasDLLImportLinkage()) {
         O << "__imp_";
       }
       O << Name;

       if (isCallOp && isa<Function>(GV)) {
         if (printGOT(TM, Subtarget)) {
           // Assemble call via PLT for non-local symbols
           if (!(GV->hasHiddenVisibility() || GV->hasProtectedVisibility()) ||
               GV->isDeclaration())
             O << "@PLT";
         }
         if (Subtarget->isTargetCygMing() && GV->isDeclaration())
           // Save function name for later type emission
           FnStubs.insert(Name);
       }
     }

     if (GV->hasExternalWeakLinkage())
       ExtWeakSymbols.insert(GV);

     int Offset = MO.getOffset();
     if (Offset > 0)
       O << "+" << Offset;
     else if (Offset < 0)
       O << Offset;

     if (isThreadLocal) {
       if (TM.getRelocationModel() == Reloc::PIC_)
         O << "@TLSGD"; // general dynamic TLS model
       else
         if (GV->isDeclaration())
           O << "@INDNTPOFF"; // initial exec TLS model
         else
           O << "@NTPOFF"; // local exec TLS model
     } else if (isMemOp) {
       if (printGOT(TM, Subtarget)) {
         if (Subtarget->GVRequiresExtraLoad(GV, TM, false))
           O << "@GOT";
         else
           O << "@GOTOFF";
       } else if (Subtarget->isPICStyleRIPRel() && !NotRIPRel) {
         if ((GV->isDeclaration() ||
              GV->hasWeakLinkage() ||
              GV->hasLinkOnceLinkage()) &&
             TM.getRelocationModel() != Reloc::Static)
           O << "@GOTPCREL";

         if (needCloseParen) {
           needCloseParen = false;
           O << ')';
         }

         // Use rip when possible to reduce code size, except when
         // index or base register are also part of the address. e.g.
         // foo(%rip)(%rcx,%rax,4) is not legal
         O << "(%rip)";
       }
     }

     if (needCloseParen)
       O << ')';

     return;
   }
   case MachineOperand::MO_ExternalSymbol: {
     bool isCallOp = Modifier && !strcmp(Modifier, "call");
     bool needCloseParen = false;
     std::string Name(TAI->getGlobalPrefix());
     Name += MO.getSymbolName();
     if (isCallOp && printStub(TM, Subtarget)) {
       FnStubs.insert(Name);
       O << TAI->getPrivateGlobalPrefix() << Name << "$stub";
       return;
     }
     if (!isCallOp)
       O << '$';
     else if (Name[0] == '$') {
       // The name begins with a dollar-sign. In order to avoid having it look
       // like an integer immediate to the assembler, enclose it in parens.
       O << '(';
       needCloseParen = true;
     }

     O << Name;

     if (printGOT(TM, Subtarget)) {
       std::string GOTName(TAI->getGlobalPrefix());
       GOTName+="_GLOBAL_OFFSET_TABLE_";
       if (Name == GOTName)
         // HACK! Emit extra offset to PC during printing GOT offset to
         // compensate for the size of popl instruction. The resulting code
         // should look like:
         //   call .piclabel
         // piclabel:
         //   popl %some_register
         //   addl $_GLOBAL_ADDRESS_TABLE_ + [.-piclabel], %some_register
         O << " + [.-"
           << computePICLabel(getFunctionNumber(), TAI, Subtarget) << "]";

       if (isCallOp)
         O << "@PLT";
     }

     if (needCloseParen)
       O << ')';

     if (!isCallOp && Subtarget->isPICStyleRIPRel())
       O << "(%rip)";

     return;
   }
   default:
     O << "<unknown operand type>"; return;
   }
 }

 void X86ATTAsmPrinter::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 X86ATTAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
                                          const char *Modifier){
   assert(isMem(MI, Op) && "Invalid memory reference!");
   MachineOperand BaseReg  = MI->getOperand(Op);
   MachineOperand IndexReg = MI->getOperand(Op+2);
   const MachineOperand &DispSpec = MI->getOperand(Op+3);

   bool NotRIPRel = IndexReg.getReg() || BaseReg.getReg();
   if (DispSpec.isGlobalAddress() ||
       DispSpec.isConstantPoolIndex() ||
       DispSpec.isJumpTableIndex()) {
     printOperand(MI, Op+3, "mem", NotRIPRel);
   } else {
     int DispVal = DispSpec.getImmedValue();
     if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg()))
       O << DispVal;
   }

   if (IndexReg.getReg() || BaseReg.getReg()) {
     unsigned ScaleVal = MI->getOperand(Op+1).getImmedValue();
     unsigned BaseRegOperand = 0, IndexRegOperand = 2;

     // There are cases where we can end up with ESP/RSP in the indexreg slot.
     // If this happens, swap the base/index register to support assemblers that
     // don't work when the index is *SP.
     if (IndexReg.getReg() == X86::ESP || IndexReg.getReg() == X86::RSP) {
       assert(ScaleVal == 1 && "Scale not supported for stack pointer!");
       std::swap(BaseReg, IndexReg);
       std::swap(BaseRegOperand, IndexRegOperand);
     }

     O << "(";
     if (BaseReg.getReg())
       printOperand(MI, Op+BaseRegOperand, Modifier);

     if (IndexReg.getReg()) {
       O << ",";
       printOperand(MI, Op+IndexRegOperand, Modifier);
       if (ScaleVal != 1)
         O << "," << ScaleVal;
     }
     O << ")";
   }
 }

 void X86ATTAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
   std::string label = computePICLabel(getFunctionNumber(), TAI, Subtarget);
   O << label << "\n" << label << ":";
 }


 bool X86ATTAsmPrinter::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 << '%';
   for (const char *Name = RI.get(Reg).Name; *Name; ++Name)
     O << (char)tolower(*Name);
   return false;
 }

 /// PrintAsmOperand - Print out an operand for an inline asm expression.
 ///
 bool X86ATTAsmPrinter::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 'c': // Don't print "$" before a global var name or constant.
       printOperand(MI, OpNo, "mem");
       return false;
     case 'b': // Print QImode register
     case 'h': // Print QImode high register
     case 'w': // Print HImode register
     case 'k': // Print SImode register
       if (MI->getOperand(OpNo).isRegister())
         return printAsmMRegister(MI->getOperand(OpNo), ExtraCode[0]);
       printOperand(MI, OpNo);
       return false;

     case 'P': // Don't print @PLT, but do print as memory.
       printOperand(MI, OpNo, "mem");
       return false;
     }
   }

   printOperand(MI, OpNo);
   return false;
 }

 bool X86ATTAsmPrinter::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 AT&T syntax to the current output stream.
 ///
 void X86ATTAsmPrinter::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);
 }

 // Include the auto-generated portion of the assembly writer.
 #include "X86GenAsmWriter.inc"
	//===-- X86ATTAsmPrinter.cpp - Convert X86 LLVM code to AT&T 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 AT&T format assembly
	// language. This printer is the output mechanism used by `llc'.
	//
	//===----------------------------------------------------------------------===//

	#define DEBUG_TYPE "asm-printer"
	#include "X86ATTAsmPrinter.h"
	#include "X86.h"
	#include "X86COFF.h"
	#include "X86MachineFunctionInfo.h"
	#include "X86TargetMachine.h"
	#include "X86TargetAsmInfo.h"
	#include "llvm/ADT/StringExtras.h"
	#include "llvm/CallingConv.h"
	#include "llvm/Module.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");

	static std::string computePICLabel(unsigned FnNum,
	const TargetAsmInfo *TAI,
	const X86Subtarget* Subtarget) {
	std::string label;
	if (Subtarget->isTargetDarwin())
	label = "\"L" + utostr_32(FnNum) + "$pb\"";
	else if (Subtarget->isTargetELF())
	label = ".Lllvm$" + utostr_32(FnNum) + "$piclabel";
	else
	assert(0 && "Don't know how to print PIC label!\n");

	return label;
	}

	/// getSectionForFunction - Return the section that we should emit the
	/// specified function body into.
	std::string X86ATTAsmPrinter::getSectionForFunction(const Function &F) const {
	switch (F.getLinkage()) {
	default: assert(0 && "Unknown linkage type!");
	case Function::InternalLinkage:
	case Function::DLLExportLinkage:
	case Function::ExternalLinkage:
	return TAI->getTextSection();
	case Function::WeakLinkage:
	case Function::LinkOnceLinkage:
	if (Subtarget->isTargetDarwin()) {
	return ".section __TEXT,__textcoal_nt,coalesced,pure_instructions";
	} else if (Subtarget->isTargetCygMing()) {
	return "\t.section\t.text$linkonce." + CurrentFnName + ",\"ax\"";
	} else {
	return "\t.section\t.llvm.linkonce.t." + CurrentFnName +
	",\"ax\",@progbits";
	}
	}
	}

	/// runOnMachineFunction - This uses the printMachineInstruction()
	/// method to print assembly for each instruction.
	///
	bool X86ATTAsmPrinter::runOnMachineFunction(MachineFunction &MF) {
	if (TAI->doesSupportDebugInformation()) {
	// Let PassManager know we need debug information and relay
	// the MachineModuleInfo address on to DwarfWriter.
	MMI = &getAnalysis<MachineModuleInfo>();
	DW.SetModuleInfo(MMI);
	}

	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 && "Unknown linkage type!");
	case Function::InternalLinkage: // Symbols default to internal.
	if (Subtarget->isTargetDarwin())
	// FIXME: This should be parameterized somewhere.
	EmitAlignment(4, F, 0, true, 0x90);
	else
	EmitAlignment(4, F); // FIXME: This should be parameterized somewhere.
	break;
	case Function::DLLExportLinkage:
	DLLExportedFns.insert(Mang->makeNameProper(F->getName(), ""));
	//FALLS THROUGH
	case Function::ExternalLinkage:
	if (Subtarget->isTargetDarwin())
	// FIXME: This should be parameterized somewhere.
	EmitAlignment(4, F, 0, true, 0x90);
	else
	EmitAlignment(4, F); // FIXME: This should be parameterized somewhere.
	O << "\t.globl\t" << CurrentFnName << "\n";
	break;
	case Function::LinkOnceLinkage:
	case Function::WeakLinkage:
	if (Subtarget->isTargetDarwin()) {
	// FIXME: This should be parameterized somewhere.
	EmitAlignment(4, F, 0, true, 0x90);
	O << "\t.globl\t" << CurrentFnName << "\n";
	O << "\t.weak_definition\t" << CurrentFnName << "\n";
	} else if (Subtarget->isTargetCygMing()) {
	EmitAlignment(4, F); // FIXME: This should be parameterized somewhere.
	O << "\t.globl\t" << CurrentFnName << "\n";
	O << "\t.linkonce discard\n";
	} else {
	EmitAlignment(4, F); // FIXME: This should be parameterized somewhere.
	O << "\t.weak\t" << CurrentFnName << "\n";
	}
	break;
	}
	if (F->hasHiddenVisibility()) {
	if (const char *Directive = TAI->getHiddenDirective())
	O << Directive << CurrentFnName << "\n";
	} else if (F->hasProtectedVisibility()) {
	if (const char *Directive = TAI->getProtectedDirective())
	O << Directive << CurrentFnName << "\n";
	}

	if (Subtarget->isTargetELF())
	O << "\t.type\t" << CurrentFnName << ",@function\n";
	else if (Subtarget->isTargetCygMing()) {
	O << "\t.def\t " << CurrentFnName
	<< ";\t.scl\t" <<
	(F->getLinkage() == Function::InternalLinkage ? COFF::C_STAT : COFF::C_EXT)
	<< ";\t.type\t" << (COFF::DT_FCN << COFF::N_BTSHFT)
	<< ";\t.endef\n";
	}

	O << CurrentFnName << ":\n";
	// Add some workaround for linkonce linkage on Cygwin\MinGW
	if (Subtarget->isTargetCygMing() &&
	(F->getLinkage() == Function::LinkOnceLinkage \|\|
	F->getLinkage() == Function::WeakLinkage))
	O << "Lllvm$workaround$fake$stub$" << CurrentFnName << ":\n";

	if (TAI->doesSupportDebugInformation()) {
	// Emit pre-function debug information.
	DW.BeginFunction(&MF);
	}

	// 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 (!I->pred_empty()) {
	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);
	}
	}

	if (TAI->hasDotTypeDotSizeDirective())
	O << "\t.size\t" << CurrentFnName << ", .-" << CurrentFnName << "\n";

	if (TAI->doesSupportDebugInformation()) {
	// Emit post-function debug information.
	DW.EndFunction();
	}

	// Print out jump tables referenced by the function.
	EmitJumpTableInfo(MF.getJumpTableInfo(), MF);

	// We didn't modify anything.
	return false;
	}

	static inline bool printGOT(TargetMachine &TM, const X86Subtarget* ST) {
	return ST->isPICStyleGOT() && TM.getRelocationModel() == Reloc::PIC_;
	}

	static inline bool printStub(TargetMachine &TM, const X86Subtarget* ST) {
	return ST->isPICStyleStub() && TM.getRelocationModel() != Reloc::Static;
	}

	void X86ATTAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
	const char *Modifier, bool NotRIPRel) {
	const MachineOperand &MO = MI->getOperand(OpNo);
	const MRegisterInfo &RI = *TM.getRegisterInfo();
	switch (MO.getType()) {
	case MachineOperand::MO_Register: {
	assert(MRegisterInfo::isPhysicalRegister(MO.getReg()) &&
	"Virtual registers should not make it this far!");
	O << '%';
	unsigned Reg = MO.getReg();
	if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) {
	MVT::ValueType VT = (strcmp(Modifier+6,"64") == 0) ?
	MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 :
	((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8));
	Reg = getX86SubSuperRegister(Reg, VT);
	}
	for (const char Name = RI.get(Reg).Name; Name; ++Name)
	O << (char)tolower(*Name);
	return;
	}

	case MachineOperand::MO_Immediate:
	if (!Modifier \|\|
	(strcmp(Modifier, "debug") && strcmp(Modifier, "mem")))
	O << '$';
	O << MO.getImmedValue();
	return;
	case MachineOperand::MO_MachineBasicBlock:
	printBasicBlockLabel(MO.getMachineBasicBlock());
	return;
	case MachineOperand::MO_JumpTableIndex: {
	bool isMemOp = Modifier && !strcmp(Modifier, "mem");
	if (!isMemOp) O << '$';
	O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() << "_"
	<< MO.getJumpTableIndex();

	if (TM.getRelocationModel() == Reloc::PIC_) {
	if (Subtarget->isPICStyleStub())
	O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
	<< "$pb\"";
	else if (Subtarget->isPICStyleGOT())
	O << "@GOTOFF";
	}

	if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
	O << "(%rip)";
	return;
	}
	case MachineOperand::MO_ConstantPoolIndex: {
	bool isMemOp = Modifier && !strcmp(Modifier, "mem");
	if (!isMemOp) O << '$';
	O << TAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber() << "_"
	<< MO.getConstantPoolIndex();

	if (TM.getRelocationModel() == Reloc::PIC_) {
	if (Subtarget->isPICStyleStub())
	O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
	<< "$pb\"";
	else if (Subtarget->isPICStyleGOT())
	O << "@GOTOFF";
	}

	int Offset = MO.getOffset();
	if (Offset > 0)
	O << "+" << Offset;
	else if (Offset < 0)
	O << Offset;

	if (isMemOp && Subtarget->isPICStyleRIPRel() && !NotRIPRel)
	O << "(%rip)";
	return;
	}
	case MachineOperand::MO_GlobalAddress: {
	bool isCallOp = Modifier && !strcmp(Modifier, "call");
	bool isMemOp = Modifier && !strcmp(Modifier, "mem");
	bool needCloseParen = false;

	GlobalValue *GV = MO.getGlobal();
	GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
	bool isThreadLocal = GVar && GVar->isThreadLocal();

	std::string Name = Mang->getValueName(GV);
	X86SharedAsmPrinter::decorateName(Name, GV);

	if (!isMemOp && !isCallOp)
	O << '$';
	else if (Name[0] == '$') {
	// The name begins with a dollar-sign. In order to avoid having it look
	// like an integer immediate to the assembler, enclose it in parens.
	O << '(';
	needCloseParen = true;
	}

	if (printStub(TM, Subtarget)) {
	// Link-once, declaration, or Weakly-linked global variables need
	// non-lazily-resolved stubs
	if (GV->isDeclaration() \|\|
	GV->hasWeakLinkage() \|\|
	GV->hasLinkOnceLinkage()) {
	// Dynamically-resolved functions need a stub for the function.
	if (isCallOp && isa<Function>(GV)) {
	FnStubs.insert(Name);
	O << TAI->getPrivateGlobalPrefix() << Name << "$stub";
	} else {
	GVStubs.insert(Name);
	O << TAI->getPrivateGlobalPrefix() << Name << "$non_lazy_ptr";
	}
	} else {
	if (GV->hasDLLImportLinkage())
	O << "__imp_";
	O << Name;
	}

	if (!isCallOp && TM.getRelocationModel() == Reloc::PIC_)
	O << "-\"" << TAI->getPrivateGlobalPrefix() << getFunctionNumber()
	<< "$pb\"";
	} else {
	if (GV->hasDLLImportLinkage()) {
	O << "__imp_";
	}
	O << Name;

	if (isCallOp && isa<Function>(GV)) {
	if (printGOT(TM, Subtarget)) {
	// Assemble call via PLT for non-local symbols
	if (!(GV->hasHiddenVisibility() \|\| GV->hasProtectedVisibility()) \|\|
	GV->isDeclaration())
	O << "@PLT";
	}
	if (Subtarget->isTargetCygMing() && GV->isDeclaration())
	// Save function name for later type emission
	FnStubs.insert(Name);
	}
	}

	if (GV->hasExternalWeakLinkage())
	ExtWeakSymbols.insert(GV);

	int Offset = MO.getOffset();
	if (Offset > 0)
	O << "+" << Offset;
	else if (Offset < 0)
	O << Offset;

	if (isThreadLocal) {
	if (TM.getRelocationModel() == Reloc::PIC_)
	O << "@TLSGD"; // general dynamic TLS model
	else
	if (GV->isDeclaration())
	O << "@INDNTPOFF"; // initial exec TLS model
	else
	O << "@NTPOFF"; // local exec TLS model
	} else if (isMemOp) {
	if (printGOT(TM, Subtarget)) {
	if (Subtarget->GVRequiresExtraLoad(GV, TM, false))
	O << "@GOT";
	else
	O << "@GOTOFF";
	} else if (Subtarget->isPICStyleRIPRel() && !NotRIPRel) {
	if ((GV->isDeclaration() \|\|
	GV->hasWeakLinkage() \|\|
	GV->hasLinkOnceLinkage()) &&
	TM.getRelocationModel() != Reloc::Static)
	O << "@GOTPCREL";

	if (needCloseParen) {
	needCloseParen = false;
	O << ')';
	}

	// Use rip when possible to reduce code size, except when
	// index or base register are also part of the address. e.g.
	// foo(%rip)(%rcx,%rax,4) is not legal
	O << "(%rip)";
	}
	}

	if (needCloseParen)
	O << ')';

	return;
	}
	case MachineOperand::MO_ExternalSymbol: {
	bool isCallOp = Modifier && !strcmp(Modifier, "call");
	bool needCloseParen = false;
	std::string Name(TAI->getGlobalPrefix());
	Name += MO.getSymbolName();
	if (isCallOp && printStub(TM, Subtarget)) {
	FnStubs.insert(Name);
	O << TAI->getPrivateGlobalPrefix() << Name << "$stub";
	return;
	}
	if (!isCallOp)
	O << '$';
	else if (Name[0] == '$') {
	// The name begins with a dollar-sign. In order to avoid having it look
	// like an integer immediate to the assembler, enclose it in parens.
	O << '(';
	needCloseParen = true;
	}

	O << Name;

	if (printGOT(TM, Subtarget)) {
	std::string GOTName(TAI->getGlobalPrefix());
	GOTName+="_GLOBAL_OFFSET_TABLE_";
	if (Name == GOTName)
	// HACK! Emit extra offset to PC during printing GOT offset to
	// compensate for the size of popl instruction. The resulting code
	// should look like:
	// call .piclabel
	// piclabel:
	// popl %some_register
	// addl $_GLOBAL_ADDRESS_TABLE_ + [.-piclabel], %some_register
	O << " + [.-"
	<< computePICLabel(getFunctionNumber(), TAI, Subtarget) << "]";

	if (isCallOp)
	O << "@PLT";
	}

	if (needCloseParen)
	O << ')';

	if (!isCallOp && Subtarget->isPICStyleRIPRel())
	O << "(%rip)";

	return;
	}
	default:
	O << "<unknown operand type>"; return;
	}
	}

	void X86ATTAsmPrinter::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 X86ATTAsmPrinter::printMemReference(const MachineInstr *MI, unsigned Op,
	const char *Modifier){
	assert(isMem(MI, Op) && "Invalid memory reference!");
	MachineOperand BaseReg = MI->getOperand(Op);
	MachineOperand IndexReg = MI->getOperand(Op+2);
	const MachineOperand &DispSpec = MI->getOperand(Op+3);

	bool NotRIPRel = IndexReg.getReg() \|\| BaseReg.getReg();
	if (DispSpec.isGlobalAddress() \|\|
	DispSpec.isConstantPoolIndex() \|\|
	DispSpec.isJumpTableIndex()) {
	printOperand(MI, Op+3, "mem", NotRIPRel);
	} else {
	int DispVal = DispSpec.getImmedValue();
	if (DispVal \|\| (!IndexReg.getReg() && !BaseReg.getReg()))
	O << DispVal;
	}

	if (IndexReg.getReg() \|\| BaseReg.getReg()) {
	unsigned ScaleVal = MI->getOperand(Op+1).getImmedValue();
	unsigned BaseRegOperand = 0, IndexRegOperand = 2;

	// There are cases where we can end up with ESP/RSP in the indexreg slot.
	// If this happens, swap the base/index register to support assemblers that
	// don't work when the index is *SP.
	if (IndexReg.getReg() == X86::ESP \|\| IndexReg.getReg() == X86::RSP) {
	assert(ScaleVal == 1 && "Scale not supported for stack pointer!");
	std::swap(BaseReg, IndexReg);
	std::swap(BaseRegOperand, IndexRegOperand);
	}

	O << "(";
	if (BaseReg.getReg())
	printOperand(MI, Op+BaseRegOperand, Modifier);

	if (IndexReg.getReg()) {
	O << ",";
	printOperand(MI, Op+IndexRegOperand, Modifier);
	if (ScaleVal != 1)
	O << "," << ScaleVal;
	}
	O << ")";
	}
	}

	void X86ATTAsmPrinter::printPICLabel(const MachineInstr *MI, unsigned Op) {
	std::string label = computePICLabel(getFunctionNumber(), TAI, Subtarget);
	O << label << "\n" << label << ":";
	}


	bool X86ATTAsmPrinter::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 << '%';
	for (const char Name = RI.get(Reg).Name; Name; ++Name)
	O << (char)tolower(*Name);
	return false;
	}

	/// PrintAsmOperand - Print out an operand for an inline asm expression.
	///
	bool X86ATTAsmPrinter::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 'c': // Don't print "$" before a global var name or constant.
	printOperand(MI, OpNo, "mem");
	return false;
	case 'b': // Print QImode register
	case 'h': // Print QImode high register
	case 'w': // Print HImode register
	case 'k': // Print SImode register
	if (MI->getOperand(OpNo).isRegister())
	return printAsmMRegister(MI->getOperand(OpNo), ExtraCode[0]);
	printOperand(MI, OpNo);
	return false;

	case 'P': // Don't print @PLT, but do print as memory.
	printOperand(MI, OpNo, "mem");
	return false;
	}
	}

	printOperand(MI, OpNo);
	return false;
	}

	bool X86ATTAsmPrinter::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 AT&T syntax to the current output stream.
	///
	void X86ATTAsmPrinter::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);
	}

	// Include the auto-generated portion of the assembly writer.
	#include "X86GenAsmWriter.inc"