llvm-project/llvm/lib/Target/PowerPC/PPCAsmPrinter.cpp

687 lines
25 KiB
C++

//===-- PPCAsmPrinter.cpp - Print machine instrs to PowerPC 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 PowerPC assembly language. This printer is
// the output mechanism used by `llc'.
//
// Documentation at http://developer.apple.com/documentation/DeveloperTools/
// Reference/Assembler/ASMIntroduction/chapter_1_section_1.html
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "asmprinter"
#include "PPC.h"
#include "PPCTargetMachine.h"
#include "PPCSubtarget.h"
#include "MCTargetDesc/PPCPredicates.h"
#include "llvm/Analysis/DebugInfo.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Module.h"
#include "llvm/Assembly/Writer.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Target/Mangler.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegistry.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/SmallString.h"
#include "InstPrinter/PPCInstPrinter.h"
using namespace llvm;
namespace {
class PPCAsmPrinter : public AsmPrinter {
protected:
DenseMap<MCSymbol*, MCSymbol*> TOC;
const PPCSubtarget &Subtarget;
uint64_t TOCLabelID;
public:
explicit PPCAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: AsmPrinter(TM, Streamer),
Subtarget(TM.getSubtarget<PPCSubtarget>()), TOCLabelID(0) {}
virtual const char *getPassName() const {
return "PowerPC Assembly Printer";
}
virtual void EmitInstruction(const MachineInstr *MI);
void printOperand(const MachineInstr *MI, unsigned OpNo, raw_ostream &O);
bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode,
raw_ostream &O);
bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode,
raw_ostream &O);
MachineLocation getDebugValueLocation(const MachineInstr *MI) const {
MachineLocation Location;
assert(MI->getNumOperands() == 4 && "Invalid no. of machine operands!");
// Frame address. Currently handles register +- offset only.
if (MI->getOperand(0).isReg() && MI->getOperand(2).isImm())
Location.set(MI->getOperand(0).getReg(), MI->getOperand(2).getImm());
else {
DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n");
}
return Location;
}
};
/// PPCLinuxAsmPrinter - PowerPC assembly printer, customized for Linux
class PPCLinuxAsmPrinter : public PPCAsmPrinter {
public:
explicit PPCLinuxAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: PPCAsmPrinter(TM, Streamer) {}
virtual const char *getPassName() const {
return "Linux PPC Assembly Printer";
}
bool doFinalization(Module &M);
virtual void EmitFunctionEntryLabel();
};
/// PPCDarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac
/// OS X
class PPCDarwinAsmPrinter : public PPCAsmPrinter {
public:
explicit PPCDarwinAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: PPCAsmPrinter(TM, Streamer) {}
virtual const char *getPassName() const {
return "Darwin PPC Assembly Printer";
}
bool doFinalization(Module &M);
void EmitStartOfAsmFile(Module &M);
void EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs);
};
} // end of anonymous namespace
/// stripRegisterPrefix - This method strips the character prefix from a
/// register name so that only the number is left. Used by for linux asm.
static const char *stripRegisterPrefix(const char *RegName) {
switch (RegName[0]) {
case 'r':
case 'f':
case 'v': return RegName + 1;
case 'c': if (RegName[1] == 'r') return RegName + 2;
}
return RegName;
}
void PPCAsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNo,
raw_ostream &O) {
const MachineOperand &MO = MI->getOperand(OpNo);
switch (MO.getType()) {
case MachineOperand::MO_Register: {
const char *RegName = PPCInstPrinter::getRegisterName(MO.getReg());
// Linux assembler (Others?) does not take register mnemonics.
// FIXME - What about special registers used in mfspr/mtspr?
if (!Subtarget.isDarwin()) RegName = stripRegisterPrefix(RegName);
O << RegName;
return;
}
case MachineOperand::MO_Immediate:
O << MO.getImm();
return;
case MachineOperand::MO_MachineBasicBlock:
O << *MO.getMBB()->getSymbol();
return;
case MachineOperand::MO_JumpTableIndex:
O << MAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber()
<< '_' << MO.getIndex();
// FIXME: PIC relocation model
return;
case MachineOperand::MO_ConstantPoolIndex:
O << MAI->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
<< '_' << MO.getIndex();
return;
case MachineOperand::MO_BlockAddress:
O << *GetBlockAddressSymbol(MO.getBlockAddress());
return;
case MachineOperand::MO_ExternalSymbol: {
// Computing the address of an external symbol, not calling it.
if (TM.getRelocationModel() == Reloc::Static) {
O << *GetExternalSymbolSymbol(MO.getSymbolName());
return;
}
MCSymbol *NLPSym =
OutContext.GetOrCreateSymbol(StringRef(MAI->getGlobalPrefix())+
MO.getSymbolName()+"$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(NLPSym);
if (StubSym.getPointer() == 0)
StubSym = MachineModuleInfoImpl::
StubValueTy(GetExternalSymbolSymbol(MO.getSymbolName()), true);
O << *NLPSym;
return;
}
case MachineOperand::MO_GlobalAddress: {
// Computing the address of a global symbol, not calling it.
const GlobalValue *GV = MO.getGlobal();
MCSymbol *SymToPrint;
// External or weakly linked global variables need non-lazily-resolved stubs
if (TM.getRelocationModel() != Reloc::Static &&
(GV->isDeclaration() || GV->isWeakForLinker())) {
if (!GV->hasHiddenVisibility()) {
SymToPrint = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMI->getObjFileInfo<MachineModuleInfoMachO>()
.getGVStubEntry(SymToPrint);
if (StubSym.getPointer() == 0)
StubSym = MachineModuleInfoImpl::
StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
} else if (GV->isDeclaration() || GV->hasCommonLinkage() ||
GV->hasAvailableExternallyLinkage()) {
SymToPrint = GetSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMI->getObjFileInfo<MachineModuleInfoMachO>().
getHiddenGVStubEntry(SymToPrint);
if (StubSym.getPointer() == 0)
StubSym = MachineModuleInfoImpl::
StubValueTy(Mang->getSymbol(GV), !GV->hasInternalLinkage());
} else {
SymToPrint = Mang->getSymbol(GV);
}
} else {
SymToPrint = Mang->getSymbol(GV);
}
O << *SymToPrint;
printOffset(MO.getOffset(), O);
return;
}
default:
O << "<unknown operand type: " << MO.getType() << ">";
return;
}
}
/// PrintAsmOperand - Print out an operand for an inline asm expression.
///
bool PPCAsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode, raw_ostream &O) {
// Does this asm operand have a single letter operand modifier?
if (ExtraCode && ExtraCode[0]) {
if (ExtraCode[1] != 0) return true; // Unknown modifier.
switch (ExtraCode[0]) {
default: return true; // Unknown modifier.
case 'c': // Don't print "$" before a global var name or constant.
break; // PPC never has a prefix.
case 'L': // Write second word of DImode reference.
// Verify that this operand has two consecutive registers.
if (!MI->getOperand(OpNo).isReg() ||
OpNo+1 == MI->getNumOperands() ||
!MI->getOperand(OpNo+1).isReg())
return true;
++OpNo; // Return the high-part.
break;
case 'I':
// Write 'i' if an integer constant, otherwise nothing. Used to print
// addi vs add, etc.
if (MI->getOperand(OpNo).isImm())
O << "i";
return false;
}
}
printOperand(MI, OpNo, O);
return false;
}
// At the moment, all inline asm memory operands are a single register.
// In any case, the output of this routine should always be just one
// assembler operand.
bool PPCAsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant,
const char *ExtraCode,
raw_ostream &O) {
if (ExtraCode && ExtraCode[0])
return true; // Unknown modifier.
assert(MI->getOperand(OpNo).isReg());
O << "0(";
printOperand(MI, OpNo, O);
O << ")";
return false;
}
/// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
/// the current output stream.
///
void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
MCInst TmpInst;
// Lower multi-instruction pseudo operations.
switch (MI->getOpcode()) {
default: break;
case TargetOpcode::DBG_VALUE: {
if (!isVerbose() || !OutStreamer.hasRawTextSupport()) return;
SmallString<32> Str;
raw_svector_ostream O(Str);
unsigned NOps = MI->getNumOperands();
assert(NOps==4);
O << '\t' << MAI->getCommentString() << "DEBUG_VALUE: ";
// cast away const; DIetc do not take const operands for some reason.
DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps-1).getMetadata()));
O << V.getName();
O << " <- ";
// Frame address. Currently handles register +- offset only.
assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm());
O << '['; printOperand(MI, 0, O); O << '+'; printOperand(MI, 1, O);
O << ']';
O << "+";
printOperand(MI, NOps-2, O);
OutStreamer.EmitRawText(O.str());
return;
}
case PPC::MovePCtoLR:
case PPC::MovePCtoLR8: {
// Transform %LR = MovePCtoLR
// Into this, where the label is the PIC base:
// bl L1$pb
// L1$pb:
MCSymbol *PICBase = MF->getPICBaseSymbol();
// Emit the 'bl'.
TmpInst.setOpcode(PPC::BL_Darwin); // Darwin vs SVR4 doesn't matter here.
// FIXME: We would like an efficient form for this, so we don't have to do
// a lot of extra uniquing.
TmpInst.addOperand(MCOperand::CreateExpr(MCSymbolRefExpr::
Create(PICBase, OutContext)));
OutStreamer.EmitInstruction(TmpInst);
// Emit the label.
OutStreamer.EmitLabel(PICBase);
return;
}
case PPC::LDtoc: {
// Transform %X3 = LDtoc <ga:@min1>, %X2
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to LD, and the global address operand to be a
// reference to the TOC entry we will synthesize later.
TmpInst.setOpcode(PPC::LD);
const MachineOperand &MO = MI->getOperand(1);
assert(MO.isGlobal());
// Map symbol -> label of TOC entry.
MCSymbol *&TOCEntry = TOC[Mang->getSymbol(MO.getGlobal())];
if (TOCEntry == 0)
TOCEntry = GetTempSymbol("C", TOCLabelID++);
const MCExpr *Exp =
MCSymbolRefExpr::Create(TOCEntry, MCSymbolRefExpr::VK_PPC_TOC,
OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
OutStreamer.EmitInstruction(TmpInst);
return;
}
case PPC::MFCRpseud:
// Transform: %R3 = MFCRpseud %CR7
// Into: %R3 = MFCR ;; cr7
OutStreamer.AddComment(PPCInstPrinter::
getRegisterName(MI->getOperand(1).getReg()));
TmpInst.setOpcode(PPC::MFCR);
TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg()));
OutStreamer.EmitInstruction(TmpInst);
return;
}
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
OutStreamer.EmitInstruction(TmpInst);
}
void PPCLinuxAsmPrinter::EmitFunctionEntryLabel() {
if (!Subtarget.isPPC64()) // linux/ppc32 - Normal entry label.
return AsmPrinter::EmitFunctionEntryLabel();
// Emit an official procedure descriptor.
// FIXME 64-bit SVR4: Use MCSection here!
OutStreamer.EmitRawText(StringRef("\t.section\t\".opd\",\"aw\""));
OutStreamer.EmitRawText(StringRef("\t.align 3"));
OutStreamer.EmitLabel(CurrentFnSym);
OutStreamer.EmitRawText("\t.quad .L." + Twine(CurrentFnSym->getName()) +
",.TOC.@tocbase");
OutStreamer.EmitRawText(StringRef("\t.previous"));
OutStreamer.EmitRawText(".L." + Twine(CurrentFnSym->getName()) + ":");
}
bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
const TargetData *TD = TM.getTargetData();
bool isPPC64 = TD->getPointerSizeInBits() == 64;
if (isPPC64 && !TOC.empty()) {
// FIXME 64-bit SVR4: Use MCSection here?
OutStreamer.EmitRawText(StringRef("\t.section\t\".toc\",\"aw\""));
// FIXME: This is nondeterminstic!
for (DenseMap<MCSymbol*, MCSymbol*>::iterator I = TOC.begin(),
E = TOC.end(); I != E; ++I) {
OutStreamer.EmitLabel(I->second);
OutStreamer.EmitRawText("\t.tc " + Twine(I->first->getName()) +
"[TC]," + I->first->getName());
}
}
return AsmPrinter::doFinalization(M);
}
void PPCDarwinAsmPrinter::EmitStartOfAsmFile(Module &M) {
static const char *const CPUDirectives[] = {
"",
"ppc",
"ppc601",
"ppc602",
"ppc603",
"ppc7400",
"ppc750",
"ppc970",
"ppc64"
};
unsigned Directive = Subtarget.getDarwinDirective();
if (Subtarget.isGigaProcessor() && Directive < PPC::DIR_970)
Directive = PPC::DIR_970;
if (Subtarget.hasAltivec() && Directive < PPC::DIR_7400)
Directive = PPC::DIR_7400;
if (Subtarget.isPPC64() && Directive < PPC::DIR_970)
Directive = PPC::DIR_64;
assert(Directive <= PPC::DIR_64 && "Directive out of range.");
// FIXME: This is a total hack, finish mc'izing the PPC backend.
if (OutStreamer.hasRawTextSupport())
OutStreamer.EmitRawText("\t.machine " + Twine(CPUDirectives[Directive]));
// Prime text sections so they are adjacent. This reduces the likelihood a
// large data or debug section causes a branch to exceed 16M limit.
const TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
OutStreamer.SwitchSection(TLOFMacho.getTextCoalSection());
if (TM.getRelocationModel() == Reloc::PIC_) {
OutStreamer.SwitchSection(
OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
MCSectionMachO::S_SYMBOL_STUBS |
MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
32, SectionKind::getText()));
} else if (TM.getRelocationModel() == Reloc::DynamicNoPIC) {
OutStreamer.SwitchSection(
OutContext.getMachOSection("__TEXT","__symbol_stub1",
MCSectionMachO::S_SYMBOL_STUBS |
MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
16, SectionKind::getText()));
}
OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
}
static MCSymbol *GetLazyPtr(MCSymbol *Sym, MCContext &Ctx) {
// Remove $stub suffix, add $lazy_ptr.
SmallString<128> TmpStr(Sym->getName().begin(), Sym->getName().end()-5);
TmpStr += "$lazy_ptr";
return Ctx.GetOrCreateSymbol(TmpStr.str());
}
static MCSymbol *GetAnonSym(MCSymbol *Sym, MCContext &Ctx) {
// Add $tmp suffix to $stub, yielding $stub$tmp.
SmallString<128> TmpStr(Sym->getName().begin(), Sym->getName().end());
TmpStr += "$tmp";
return Ctx.GetOrCreateSymbol(TmpStr.str());
}
void PPCDarwinAsmPrinter::
EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs) {
bool isPPC64 = TM.getTargetData()->getPointerSizeInBits() == 64;
const TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
// .lazy_symbol_pointer
const MCSection *LSPSection = TLOFMacho.getLazySymbolPointerSection();
// Output stubs for dynamically-linked functions
if (TM.getRelocationModel() == Reloc::PIC_) {
const MCSection *StubSection =
OutContext.getMachOSection("__TEXT", "__picsymbolstub1",
MCSectionMachO::S_SYMBOL_STUBS |
MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
32, SectionKind::getText());
for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
OutStreamer.SwitchSection(StubSection);
EmitAlignment(4);
MCSymbol *Stub = Stubs[i].first;
MCSymbol *RawSym = Stubs[i].second.getPointer();
MCSymbol *LazyPtr = GetLazyPtr(Stub, OutContext);
MCSymbol *AnonSymbol = GetAnonSym(Stub, OutContext);
OutStreamer.EmitLabel(Stub);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
// FIXME: MCize this.
OutStreamer.EmitRawText(StringRef("\tmflr r0"));
OutStreamer.EmitRawText("\tbcl 20,31," + Twine(AnonSymbol->getName()));
OutStreamer.EmitLabel(AnonSymbol);
OutStreamer.EmitRawText(StringRef("\tmflr r11"));
OutStreamer.EmitRawText("\taddis r11,r11,ha16("+Twine(LazyPtr->getName())+
"-" + AnonSymbol->getName() + ")");
OutStreamer.EmitRawText(StringRef("\tmtlr r0"));
if (isPPC64)
OutStreamer.EmitRawText("\tldu r12,lo16(" + Twine(LazyPtr->getName()) +
"-" + AnonSymbol->getName() + ")(r11)");
else
OutStreamer.EmitRawText("\tlwzu r12,lo16(" + Twine(LazyPtr->getName()) +
"-" + AnonSymbol->getName() + ")(r11)");
OutStreamer.EmitRawText(StringRef("\tmtctr r12"));
OutStreamer.EmitRawText(StringRef("\tbctr"));
OutStreamer.SwitchSection(LSPSection);
OutStreamer.EmitLabel(LazyPtr);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
if (isPPC64)
OutStreamer.EmitRawText(StringRef("\t.quad dyld_stub_binding_helper"));
else
OutStreamer.EmitRawText(StringRef("\t.long dyld_stub_binding_helper"));
}
OutStreamer.AddBlankLine();
return;
}
const MCSection *StubSection =
OutContext.getMachOSection("__TEXT","__symbol_stub1",
MCSectionMachO::S_SYMBOL_STUBS |
MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
16, SectionKind::getText());
for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
MCSymbol *Stub = Stubs[i].first;
MCSymbol *RawSym = Stubs[i].second.getPointer();
MCSymbol *LazyPtr = GetLazyPtr(Stub, OutContext);
OutStreamer.SwitchSection(StubSection);
EmitAlignment(4);
OutStreamer.EmitLabel(Stub);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
OutStreamer.EmitRawText("\tlis r11,ha16(" + Twine(LazyPtr->getName()) +")");
if (isPPC64)
OutStreamer.EmitRawText("\tldu r12,lo16(" + Twine(LazyPtr->getName()) +
")(r11)");
else
OutStreamer.EmitRawText("\tlwzu r12,lo16(" + Twine(LazyPtr->getName()) +
")(r11)");
OutStreamer.EmitRawText(StringRef("\tmtctr r12"));
OutStreamer.EmitRawText(StringRef("\tbctr"));
OutStreamer.SwitchSection(LSPSection);
OutStreamer.EmitLabel(LazyPtr);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
if (isPPC64)
OutStreamer.EmitRawText(StringRef("\t.quad dyld_stub_binding_helper"));
else
OutStreamer.EmitRawText(StringRef("\t.long dyld_stub_binding_helper"));
}
OutStreamer.AddBlankLine();
}
bool PPCDarwinAsmPrinter::doFinalization(Module &M) {
bool isPPC64 = TM.getTargetData()->getPointerSizeInBits() == 64;
// Darwin/PPC always uses mach-o.
const TargetLoweringObjectFileMachO &TLOFMacho =
static_cast<const TargetLoweringObjectFileMachO &>(getObjFileLowering());
MachineModuleInfoMachO &MMIMacho =
MMI->getObjFileInfo<MachineModuleInfoMachO>();
MachineModuleInfoMachO::SymbolListTy Stubs = MMIMacho.GetFnStubList();
if (!Stubs.empty())
EmitFunctionStubs(Stubs);
if (MAI->doesSupportExceptionHandling() && MMI) {
// Add the (possibly multiple) personalities to the set of global values.
// Only referenced functions get into the Personalities list.
const std::vector<const Function*> &Personalities = MMI->getPersonalities();
for (std::vector<const Function*>::const_iterator I = Personalities.begin(),
E = Personalities.end(); I != E; ++I) {
if (*I) {
MCSymbol *NLPSym = GetSymbolWithGlobalValueBase(*I, "$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMIMacho.getGVStubEntry(NLPSym);
StubSym = MachineModuleInfoImpl::StubValueTy(Mang->getSymbol(*I), true);
}
}
}
// Output stubs for dynamically-linked functions.
Stubs = MMIMacho.GetGVStubList();
// Output macho stubs for external and common global variables.
if (!Stubs.empty()) {
// Switch with ".non_lazy_symbol_pointer" directive.
OutStreamer.SwitchSection(TLOFMacho.getNonLazySymbolPointerSection());
EmitAlignment(isPPC64 ? 3 : 2);
for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
// L_foo$stub:
OutStreamer.EmitLabel(Stubs[i].first);
// .indirect_symbol _foo
MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol);
if (MCSym.getInt())
// External to current translation unit.
OutStreamer.EmitIntValue(0, isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
else
// Internal to current translation unit.
//
// When we place the LSDA into the TEXT section, the type info pointers
// need to be indirect and pc-rel. We accomplish this by using NLPs.
// However, sometimes the types are local to the file. So we need to
// fill in the value for the NLP in those cases.
OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
OutContext),
isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
}
Stubs.clear();
OutStreamer.AddBlankLine();
}
Stubs = MMIMacho.GetHiddenGVStubList();
if (!Stubs.empty()) {
OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
EmitAlignment(isPPC64 ? 3 : 2);
for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
// L_foo$stub:
OutStreamer.EmitLabel(Stubs[i].first);
// .long _foo
OutStreamer.EmitValue(MCSymbolRefExpr::
Create(Stubs[i].second.getPointer(),
OutContext),
isPPC64 ? 8 : 4/*size*/, 0/*addrspace*/);
}
Stubs.clear();
OutStreamer.AddBlankLine();
}
// 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.
OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
return AsmPrinter::doFinalization(M);
}
/// createPPCAsmPrinterPass - Returns a pass that prints the PPC assembly code
/// for a MachineFunction to the given output stream, in a format that the
/// Darwin assembler can deal with.
///
static AsmPrinter *createPPCAsmPrinterPass(TargetMachine &tm,
MCStreamer &Streamer) {
const PPCSubtarget *Subtarget = &tm.getSubtarget<PPCSubtarget>();
if (Subtarget->isDarwin())
return new PPCDarwinAsmPrinter(tm, Streamer);
return new PPCLinuxAsmPrinter(tm, Streamer);
}
// Force static initialization.
extern "C" void LLVMInitializePowerPCAsmPrinter() {
TargetRegistry::RegisterAsmPrinter(ThePPC32Target, createPPCAsmPrinterPass);
TargetRegistry::RegisterAsmPrinter(ThePPC64Target, createPPCAsmPrinterPass);
}