llvm/lib/Target/X86/X86AsmPrinter.cpp - toolchain/llvm-project - Gitiles

 //===-- X86AsmPrinter.cpp - Convert X86 LLVM IR to X86 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 the shared super class printer that converts from our internal
 // representation of machine-dependent LLVM code to Intel and AT&T format
 // assembly language.
 // This printer is the output mechanism used by `llc'.
 //
 //===----------------------------------------------------------------------===//

 #include "X86AsmPrinter.h"
 #include "X86ATTAsmPrinter.h"
 #include "X86IntelAsmPrinter.h"
 #include "X86MachineFunctionInfo.h"
 #include "X86Subtarget.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/CallingConv.h"
 #include "llvm/Constants.h"
 #include "llvm/Module.h"
 #include "llvm/Type.h"
 #include "llvm/Assembly/Writer.h"
 #include "llvm/Support/Mangler.h"
 #include "llvm/Target/TargetAsmInfo.h"

 using namespace llvm;

 Statistic<> llvm::EmittedInsts("asm-printer",
                                "Number of machine instrs printed");

 static X86FunctionInfo calculateFunctionInfo(const Function *F,
                                              const TargetData *TD) {
   X86FunctionInfo 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;
   }

   for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
        AI != AE; ++AI)
     Size += TD->getTypeSize(AI->getType());

   // Size should be aligned to DWORD boundary
   Size = ((Size + 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 X86SharedAsmPrinter::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 X86FunctionInfo *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;
   }

   switch (Info->getDecorationStyle()) {
   case None:
     break;
   case StdCall:
     if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
       Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
     break;
   case FastCall:
     if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
       Name += '@' + utostr_32(Info->getBytesToPopOnReturn());

     if (Name[0] == '_') {
       Name[0] = '@';
     } else {
       Name = '@' + Name;
     }
     break;
   default:
     assert(0 && "Unsupported DecorationStyle");
   }
 }

 /// doInitialization
 bool X86SharedAsmPrinter::doInitialization(Module &M) {
   if (Subtarget->isTargetDarwin()) {
     if (!Subtarget->is64Bit())
       X86PICStyle = PICStyle::Stub;

     // Emit initial debug information.
     DW.BeginModule(&M);
   } else if (Subtarget->isTargetELF() || Subtarget->isTargetCygwin()) {
     // Emit initial debug information.
     DW.BeginModule(&M);
   }

   return AsmPrinter::doInitialization(M);
 }

 bool X86SharedAsmPrinter::doFinalization(Module &M) {
   // Note: this code is not shared by the Intel printer as it is too different
   // from how MASM does things.  When making changes here don't forget to look
   // at X86IntelAsmPrinter::doFinalization().
   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->hasInitializer() && !I->hasExternalWeakLinkage())
       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 Size = TD->getTypeSize(C->getType());
     unsigned Align = TD->getPreferredAlignmentLog(I);

     if (C->isNullValue() && /* FIXME: Verify correct */
         !I->hasSection() &&
         (I->hasInternalLinkage() || I->hasWeakLinkage() ||
          I->hasLinkOnceLinkage() ||
          (Subtarget->isTargetDarwin() &&
           I->hasExternalLinkage()))) {
       if (Size == 0) Size = 1;   // .comm Foo, 0 is undefined, avoid it.
       if (I->hasExternalLinkage()) {
           O << "\t.globl\t" << name << "\n";
           O << "\t.zerofill __DATA__, __common, " << name << ", "
             << Size << ", " << Align;
       } else {
         SwitchToDataSection(TAI->getDataSection(), I);
         if (TAI->getLCOMMDirective() != NULL) {
           if (I->hasInternalLinkage()) {
             O << TAI->getLCOMMDirective() << name << "," << Size;
             if (Subtarget->isTargetDarwin())
               O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
           } else
             O << TAI->getCOMMDirective()  << name << "," << Size;
         } else {
           if (!Subtarget->isTargetCygwin()) {
             if (I->hasInternalLinkage())
               O << "\t.local\t" << name << "\n";
           }
           O << TAI->getCOMMDirective()  << name << "," << Size;
           if (TAI->getCOMMDirectiveTakesAlignment())
             O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
         }
       }
       O << "\t\t" << TAI->getCommentString() << " " << I->getName() << "\n";
     } else {
       switch (I->getLinkage()) {
       case GlobalValue::ExternalWeakLinkage:
        if (Subtarget->isTargetDarwin()) {
          assert(0 && "External weak linkage for Darwin not implemented yet");
        } else if (Subtarget->isTargetCygwin()) {
          // There is no external weak linkage on Mingw32 platform.
          // Defaulting just to external
          O << "\t.globl " << name << "\n";
        } else {
          O << "\t.weak " << name << "\n";
          break;
        }
       case GlobalValue::LinkOnceLinkage:
       case GlobalValue::WeakLinkage:
         if (Subtarget->isTargetDarwin()) {
           O << "\t.globl " << name << "\n"
             << "\t.weak_definition " << name << "\n";
           SwitchToDataSection(".section __DATA,__const_coal,coalesced", I);
         } else if (Subtarget->isTargetCygwin()) {
           std::string SectionName(".section\t.data$linkonce." +
                                   name +
                                   ",\"aw\"");
           SwitchToDataSection(SectionName.c_str(), I);
           O << "\t.globl " << name << "\n"
             << "\t.linkonce same_size\n";
         } else {
           std::string SectionName("\t.section\t.llvm.linkonce.d." +
                                   name +
                                   ",\"aw\",@progbits");
           SwitchToDataSection(SectionName.c_str(), I);
           O << "\t.weak " << name << "\n";
         }
         break;
       case GlobalValue::AppendingLinkage:
         // FIXME: appending linkage variables should go into a section of
         // their name or something.  For now, just emit them as external.
       case GlobalValue::DLLExportLinkage:
         DLLExportedGVs.insert(Mang->makeNameProper(I->getName(),""));
         // FALL THROUGH
       case GlobalValue::ExternalLinkage:
         // If external or appending, declare as a global symbol
         O << "\t.globl " << name << "\n";
         // FALL THROUGH
       case GlobalValue::InternalLinkage: {
         if (I->isConstant()) {
           const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
           if (TAI->getCStringSection() && CVA && CVA->isCString()) {
             SwitchToDataSection(TAI->getCStringSection(), I);
             break;
           }
         }
         // FIXME: special handling for ".ctors" & ".dtors" sections
         if (I->hasSection() &&
             (I->getSection() == ".ctors" ||
              I->getSection() == ".dtors")) {
           std::string SectionName = ".section " + I->getSection();

           if (Subtarget->isTargetCygwin()) {
             SectionName += ",\"aw\"";
           } else {
             assert(!Subtarget->isTargetDarwin());
             SectionName += ",\"aw\",@progbits";
           }

           SwitchToDataSection(SectionName.c_str());
         } else {
           SwitchToDataSection(TAI->getDataSection(), I);
         }

         break;
       }
       default:
         assert(0 && "Unknown linkage type!");
       }

       EmitAlignment(Align, I);
       O << name << ":\t\t\t\t" << TAI->getCommentString() << " " << I->getName()
         << "\n";
       if (TAI->hasDotTypeDotSizeDirective())
         O << "\t.size " << name << ", " << Size << "\n";

       EmitGlobalConstant(C);
       O << '\n';
     }
   }

   // Output linker support code for dllexported globals
   if (DLLExportedGVs.begin() != DLLExportedGVs.end()) {
     SwitchToDataSection(".section .drectve");
   }

   for (std::set<std::string>::iterator i = DLLExportedGVs.begin(),
          e = DLLExportedGVs.end();
          i != e; ++i) {
     O << "\t.ascii \" -export:" << *i << ",data\"\n";
   }

   if (DLLExportedFns.begin() != DLLExportedFns.end()) {
     SwitchToDataSection(".section .drectve");
   }

   for (std::set<std::string>::iterator i = DLLExportedFns.begin(),
          e = DLLExportedFns.end();
          i != e; ++i) {
     O << "\t.ascii \" -export:" << *i << "\"\n";
   }

   if (!Subtarget->isTargetCygwin()) {
     // There is no external weak linkage on Mingw32 platform.
     // Defaulting to external
     if (ExtWeakSymbols.begin() != ExtWeakSymbols.end())
       SwitchToDataSection("");

     for (std::set<std::string>::iterator i = ExtWeakSymbols.begin(),
          e = ExtWeakSymbols.end(); i != e; ++i) {
       O << (Subtarget->isTargetDarwin() ? "\t.weak_reference" : "\t.weak")
         << " " << *i << "\n";
     }
   }

   if (Subtarget->isTargetDarwin()) {
     SwitchToDataSection("");

     // Output stubs for dynamically-linked functions
     unsigned j = 1;
     for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
          i != e; ++i, ++j) {
       SwitchToDataSection(".section __IMPORT,__jump_table,symbol_stubs,"
                           "self_modifying_code+pure_instructions,5", 0);
       O << "L" << *i << "$stub:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       O << "\thlt ; hlt ; hlt ; hlt ; hlt\n";
     }

     O << "\n";

     // Output stubs for external and common global variables.
     if (GVStubs.begin() != GVStubs.end())
       SwitchToDataSection(
                     ".section __IMPORT,__pointers,non_lazy_symbol_pointers");
     for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
          i != e; ++i) {
       O << "L" << *i << "$non_lazy_ptr:\n";
       O << "\t.indirect_symbol " << *i << "\n";
       O << "\t.long\t0\n";
     }

     // Emit final debug information.
     DW.EndModule();

     // Funny Darwin hack: This flag tells the linker that no global symbols
     // contain code that falls through to other global symbols (e.g. the obvious
     // implementation of multiple entry points).  If this doesn't occur, the
     // linker can safely perform dead code stripping.  Since LLVM never
     // generates code that does this, it is always safe to set.
     O << "\t.subsections_via_symbols\n";
   } else if (Subtarget->isTargetELF() || Subtarget->isTargetCygwin()) {
     // Emit final debug information.
     DW.EndModule();
   }

   AsmPrinter::doFinalization(M);
   return false; // success
 }

 /// createX86CodePrinterPass - Returns a pass that prints the X86 assembly code
 /// for a MachineFunction to the given output stream, using the given target
 /// machine description.
 ///
 FunctionPass *llvm::createX86CodePrinterPass(std::ostream &o,
                                              X86TargetMachine &tm) {
   const X86Subtarget *Subtarget = &tm.getSubtarget<X86Subtarget>();

   if (Subtarget->isFlavorIntel()) {
     return new X86IntelAsmPrinter(o, tm, tm.getTargetAsmInfo());
   } else {
     return new X86ATTAsmPrinter(o, tm, tm.getTargetAsmInfo());
   }
 }
	//===-- X86AsmPrinter.cpp - Convert X86 LLVM IR to X86 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 the shared super class printer that converts from our internal
	// representation of machine-dependent LLVM code to Intel and AT&T format
	// assembly language.
	// This printer is the output mechanism used by `llc'.
	//
	//===----------------------------------------------------------------------===//

	#include "X86AsmPrinter.h"
	#include "X86ATTAsmPrinter.h"
	#include "X86IntelAsmPrinter.h"
	#include "X86MachineFunctionInfo.h"
	#include "X86Subtarget.h"
	#include "llvm/ADT/StringExtras.h"
	#include "llvm/CallingConv.h"
	#include "llvm/Constants.h"
	#include "llvm/Module.h"
	#include "llvm/Type.h"
	#include "llvm/Assembly/Writer.h"
	#include "llvm/Support/Mangler.h"
	#include "llvm/Target/TargetAsmInfo.h"

	using namespace llvm;

	Statistic<> llvm::EmittedInsts("asm-printer",
	"Number of machine instrs printed");

	static X86FunctionInfo calculateFunctionInfo(const Function *F,
	const TargetData *TD) {
	X86FunctionInfo 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;
	}

	for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
	AI != AE; ++AI)
	Size += TD->getTypeSize(AI->getType());

	// Size should be aligned to DWORD boundary
	Size = ((Size + 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 X86SharedAsmPrinter::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 X86FunctionInfo *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;
	}

	switch (Info->getDecorationStyle()) {
	case None:
	break;
	case StdCall:
	if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
	Name += '@' + utostr_32(Info->getBytesToPopOnReturn());
	break;
	case FastCall:
	if (!F->isVarArg()) // Variadic functions do not receive @0 suffix.
	Name += '@' + utostr_32(Info->getBytesToPopOnReturn());

	if (Name[0] == '_') {
	Name[0] = '@';
	} else {
	Name = '@' + Name;
	}
	break;
	default:
	assert(0 && "Unsupported DecorationStyle");
	}
	}

	/// doInitialization
	bool X86SharedAsmPrinter::doInitialization(Module &M) {
	if (Subtarget->isTargetDarwin()) {
	if (!Subtarget->is64Bit())
	X86PICStyle = PICStyle::Stub;

	// Emit initial debug information.
	DW.BeginModule(&M);
	} else if (Subtarget->isTargetELF() \|\| Subtarget->isTargetCygwin()) {
	// Emit initial debug information.
	DW.BeginModule(&M);
	}

	return AsmPrinter::doInitialization(M);
	}

	bool X86SharedAsmPrinter::doFinalization(Module &M) {
	// Note: this code is not shared by the Intel printer as it is too different
	// from how MASM does things. When making changes here don't forget to look
	// at X86IntelAsmPrinter::doFinalization().
	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->hasInitializer() && !I->hasExternalWeakLinkage())
	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 Size = TD->getTypeSize(C->getType());
	unsigned Align = TD->getPreferredAlignmentLog(I);

	if (C->isNullValue() && /* FIXME: Verify correct */
	!I->hasSection() &&
	(I->hasInternalLinkage() \|\| I->hasWeakLinkage() \|\|
	I->hasLinkOnceLinkage() \|\|
	(Subtarget->isTargetDarwin() &&
	I->hasExternalLinkage()))) {
	if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
	if (I->hasExternalLinkage()) {
	O << "\t.globl\t" << name << "\n";
	O << "\t.zerofill __DATA__, __common, " << name << ", "
	<< Size << ", " << Align;
	} else {
	SwitchToDataSection(TAI->getDataSection(), I);
	if (TAI->getLCOMMDirective() != NULL) {
	if (I->hasInternalLinkage()) {
	O << TAI->getLCOMMDirective() << name << "," << Size;
	if (Subtarget->isTargetDarwin())
	O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
	} else
	O << TAI->getCOMMDirective() << name << "," << Size;
	} else {
	if (!Subtarget->isTargetCygwin()) {
	if (I->hasInternalLinkage())
	O << "\t.local\t" << name << "\n";
	}
	O << TAI->getCOMMDirective() << name << "," << Size;
	if (TAI->getCOMMDirectiveTakesAlignment())
	O << "," << (TAI->getAlignmentIsInBytes() ? (1 << Align) : Align);
	}
	}
	O << "\t\t" << TAI->getCommentString() << " " << I->getName() << "\n";
	} else {
	switch (I->getLinkage()) {
	case GlobalValue::ExternalWeakLinkage:
	if (Subtarget->isTargetDarwin()) {
	assert(0 && "External weak linkage for Darwin not implemented yet");
	} else if (Subtarget->isTargetCygwin()) {
	// There is no external weak linkage on Mingw32 platform.
	// Defaulting just to external
	O << "\t.globl " << name << "\n";
	} else {
	O << "\t.weak " << name << "\n";
	break;
	}
	case GlobalValue::LinkOnceLinkage:
	case GlobalValue::WeakLinkage:
	if (Subtarget->isTargetDarwin()) {
	O << "\t.globl " << name << "\n"
	<< "\t.weak_definition " << name << "\n";
	SwitchToDataSection(".section __DATA,__const_coal,coalesced", I);
	} else if (Subtarget->isTargetCygwin()) {
	std::string SectionName(".section\t.data$linkonce." +
	name +
	",\"aw\"");
	SwitchToDataSection(SectionName.c_str(), I);
	O << "\t.globl " << name << "\n"
	<< "\t.linkonce same_size\n";
	} else {
	std::string SectionName("\t.section\t.llvm.linkonce.d." +
	name +
	",\"aw\",@progbits");
	SwitchToDataSection(SectionName.c_str(), I);
	O << "\t.weak " << name << "\n";
	}
	break;
	case GlobalValue::AppendingLinkage:
	// FIXME: appending linkage variables should go into a section of
	// their name or something. For now, just emit them as external.
	case GlobalValue::DLLExportLinkage:
	DLLExportedGVs.insert(Mang->makeNameProper(I->getName(),""));
	// FALL THROUGH
	case GlobalValue::ExternalLinkage:
	// If external or appending, declare as a global symbol
	O << "\t.globl " << name << "\n";
	// FALL THROUGH
	case GlobalValue::InternalLinkage: {
	if (I->isConstant()) {
	const ConstantArray *CVA = dyn_cast<ConstantArray>(C);
	if (TAI->getCStringSection() && CVA && CVA->isCString()) {
	SwitchToDataSection(TAI->getCStringSection(), I);
	break;
	}
	}
	// FIXME: special handling for ".ctors" & ".dtors" sections
	if (I->hasSection() &&
	(I->getSection() == ".ctors" \|\|
	I->getSection() == ".dtors")) {
	std::string SectionName = ".section " + I->getSection();

	if (Subtarget->isTargetCygwin()) {
	SectionName += ",\"aw\"";
	} else {
	assert(!Subtarget->isTargetDarwin());
	SectionName += ",\"aw\",@progbits";
	}

	SwitchToDataSection(SectionName.c_str());
	} else {
	SwitchToDataSection(TAI->getDataSection(), I);
	}

	break;
	}
	default:
	assert(0 && "Unknown linkage type!");
	}

	EmitAlignment(Align, I);
	O << name << ":\t\t\t\t" << TAI->getCommentString() << " " << I->getName()
	<< "\n";
	if (TAI->hasDotTypeDotSizeDirective())
	O << "\t.size " << name << ", " << Size << "\n";

	EmitGlobalConstant(C);
	O << '\n';
	}
	}

	// Output linker support code for dllexported globals
	if (DLLExportedGVs.begin() != DLLExportedGVs.end()) {
	SwitchToDataSection(".section .drectve");
	}

	for (std::set<std::string>::iterator i = DLLExportedGVs.begin(),
	e = DLLExportedGVs.end();
	i != e; ++i) {
	O << "\t.ascii \" -export:" << *i << ",data\"\n";
	}

	if (DLLExportedFns.begin() != DLLExportedFns.end()) {
	SwitchToDataSection(".section .drectve");
	}

	for (std::set<std::string>::iterator i = DLLExportedFns.begin(),
	e = DLLExportedFns.end();
	i != e; ++i) {
	O << "\t.ascii \" -export:" << *i << "\"\n";
	}

	if (!Subtarget->isTargetCygwin()) {
	// There is no external weak linkage on Mingw32 platform.
	// Defaulting to external
	if (ExtWeakSymbols.begin() != ExtWeakSymbols.end())
	SwitchToDataSection("");

	for (std::set<std::string>::iterator i = ExtWeakSymbols.begin(),
	e = ExtWeakSymbols.end(); i != e; ++i) {
	O << (Subtarget->isTargetDarwin() ? "\t.weak_reference" : "\t.weak")
	<< " " << *i << "\n";
	}
	}

	if (Subtarget->isTargetDarwin()) {
	SwitchToDataSection("");

	// Output stubs for dynamically-linked functions
	unsigned j = 1;
	for (std::set<std::string>::iterator i = FnStubs.begin(), e = FnStubs.end();
	i != e; ++i, ++j) {
	SwitchToDataSection(".section __IMPORT,__jump_table,symbol_stubs,"
	"self_modifying_code+pure_instructions,5", 0);
	O << "L" << *i << "$stub:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	O << "\thlt ; hlt ; hlt ; hlt ; hlt\n";
	}

	O << "\n";

	// Output stubs for external and common global variables.
	if (GVStubs.begin() != GVStubs.end())
	SwitchToDataSection(
	".section __IMPORT,__pointers,non_lazy_symbol_pointers");
	for (std::set<std::string>::iterator i = GVStubs.begin(), e = GVStubs.end();
	i != e; ++i) {
	O << "L" << *i << "$non_lazy_ptr:\n";
	O << "\t.indirect_symbol " << *i << "\n";
	O << "\t.long\t0\n";
	}

	// Emit final debug information.
	DW.EndModule();

	// Funny Darwin hack: This flag tells the linker that no global symbols
	// contain code that falls through to other global symbols (e.g. the obvious
	// implementation of multiple entry points). If this doesn't occur, the
	// linker can safely perform dead code stripping. Since LLVM never
	// generates code that does this, it is always safe to set.
	O << "\t.subsections_via_symbols\n";
	} else if (Subtarget->isTargetELF() \|\| Subtarget->isTargetCygwin()) {
	// Emit final debug information.
	DW.EndModule();
	}

	AsmPrinter::doFinalization(M);
	return false; // success
	}

	/// createX86CodePrinterPass - Returns a pass that prints the X86 assembly code
	/// for a MachineFunction to the given output stream, using the given target
	/// machine description.
	///
	FunctionPass *llvm::createX86CodePrinterPass(std::ostream &o,
	X86TargetMachine &tm) {
	const X86Subtarget *Subtarget = &tm.getSubtarget<X86Subtarget>();

	if (Subtarget->isFlavorIntel()) {
	return new X86IntelAsmPrinter(o, tm, tm.getTargetAsmInfo());
	} else {
	return new X86ATTAsmPrinter(o, tm, tm.getTargetAsmInfo());
	}
	}