llvm-6502/lib/Target/PowerPC/PPCAsmPrinter.cpp
Ulrich Weigand edfd4f18bc [PowerPC] ELFv2 function call changes
This patch builds upon the two preceding MC changes to implement the
basic ELFv2 function call convention.  In the ELFv1 ABI, a "function
descriptor" was associated with every function, pointing to both the
entry address and the related TOC base (and a static chain pointer
for nested functions).  Function pointers would actually refer to that
descriptor, and the indirect call sequence needed to load up both entry
address and TOC base.

In the ELFv2 ABI, there are no more function descriptors, and function
pointers simply refer to the (global) entry point of the function code.
Indirect function calls simply branch to that address, after loading it
up into r12 (as required by the ABI rules for a global entry point).
Direct function calls continue to just do a "bl" to the target symbol;
this will be resolved by the linker to the local entry point of the
target function if it is local, and to a PLT stub if it is global.
That PLT stub would then load the (global) entry point address of the
final target into r12 and branch to it.  Note that when performing a
local function call, r2 must be set up to point to the current TOC
base: if the target ends up local, the ABI requires that its local
entry point is called with r2 set up; if the target ends up global,
the PLT stub requires that r2 is set up.

This patch implements all LLVM changes to implement that scheme:
- No longer create a function descriptor when emitting a function
  definition (in EmitFunctionEntryLabel)
- Emit two entry points *if* the function needs the TOC base (r2)
  anywhere (this is done EmitFunctionBodyStart; note that this cannot
  be done in EmitFunctionBodyStart because the global entry point
  prologue code must be *part* of the function as covered by debug info).
- In order to make use tracking of r2 (as needed above) work correctly,
  mark direct function calls as implicitly using r2.
- Implement the ELFv2 indirect function call sequence (no function
  descriptors; load target address into r12).
- When creating an ELFv2 object file, emit the .abiversion 2 directive
  to tell the linker to create the appropriate version of PLT stubs.  

Reviewed by Hal Finkel.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213489 91177308-0d34-0410-b5e6-96231b3b80d8
2014-07-20 23:31:44 +00:00

1335 lines
51 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
//
//===----------------------------------------------------------------------===//
#include "PPC.h"
#include "InstPrinter/PPCInstPrinter.h"
#include "PPCMachineFunctionInfo.h"
#include "MCTargetDesc/PPCMCExpr.h"
#include "MCTargetDesc/PPCPredicates.h"
#include "PPCSubtarget.h"
#include "PPCTargetMachine.h"
#include "PPCTargetStreamer.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Mangler.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstBuilder.h"
#include "llvm/MC/MCSectionELF.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ELF.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
using namespace llvm;
#define DEBUG_TYPE "asmprinter"
namespace {
class PPCAsmPrinter : public AsmPrinter {
protected:
MapVector<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) {}
const char *getPassName() const override {
return "PowerPC Assembly Printer";
}
MCSymbol *lookUpOrCreateTOCEntry(MCSymbol *Sym);
void EmitInstruction(const MachineInstr *MI) override;
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) override;
bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo,
unsigned AsmVariant, const char *ExtraCode,
raw_ostream &O) override;
};
/// PPCLinuxAsmPrinter - PowerPC assembly printer, customized for Linux
class PPCLinuxAsmPrinter : public PPCAsmPrinter {
public:
explicit PPCLinuxAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: PPCAsmPrinter(TM, Streamer) {}
const char *getPassName() const override {
return "Linux PPC Assembly Printer";
}
bool doFinalization(Module &M) override;
void EmitStartOfAsmFile(Module &M) override;
void EmitFunctionEntryLabel() override;
void EmitFunctionBodyStart() override;
void EmitFunctionBodyEnd() override;
};
/// PPCDarwinAsmPrinter - PowerPC assembly printer, customized for Darwin/Mac
/// OS X
class PPCDarwinAsmPrinter : public PPCAsmPrinter {
public:
explicit PPCDarwinAsmPrinter(TargetMachine &TM, MCStreamer &Streamer)
: PPCAsmPrinter(TM, Streamer) {}
const char *getPassName() const override {
return "Darwin PPC Assembly Printer";
}
bool doFinalization(Module &M) override;
void EmitStartOfAsmFile(Module &M) override;
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':
if (RegName[1] == 's')
return RegName + 2;
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 DataLayout *DL = TM.getDataLayout();
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_ConstantPoolIndex:
O << DL->getPrivateGlobalPrefix() << "CPI" << getFunctionNumber()
<< '_' << MO.getIndex();
return;
case MachineOperand::MO_BlockAddress:
O << *GetBlockAddressSymbol(MO.getBlockAddress());
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, "$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMI->getObjFileInfo<MachineModuleInfoMachO>()
.getGVStubEntry(SymToPrint);
if (!StubSym.getPointer())
StubSym = MachineModuleInfoImpl::
StubValueTy(getSymbol(GV), !GV->hasInternalLinkage());
} else if (GV->isDeclaration() || GV->hasCommonLinkage() ||
GV->hasAvailableExternallyLinkage()) {
SymToPrint = getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr");
MachineModuleInfoImpl::StubValueTy &StubSym =
MMI->getObjFileInfo<MachineModuleInfoMachO>().
getHiddenGVStubEntry(SymToPrint);
if (!StubSym.getPointer())
StubSym = MachineModuleInfoImpl::
StubValueTy(getSymbol(GV), !GV->hasInternalLinkage());
} else {
SymToPrint = getSymbol(GV);
}
} else {
SymToPrint = getSymbol(GV);
}
O << *SymToPrint;
printOffset(MO.getOffset(), O);
return;
}
default:
O << "<unknown operand type: " << (unsigned)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:
// See if this is a generic print operand
return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O);
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]) {
if (ExtraCode[1] != 0) return true; // Unknown modifier.
switch (ExtraCode[0]) {
default: return true; // Unknown modifier.
case 'y': // A memory reference for an X-form instruction
{
const char *RegName = "r0";
if (!Subtarget.isDarwin()) RegName = stripRegisterPrefix(RegName);
O << RegName << ", ";
printOperand(MI, OpNo, O);
return false;
}
}
}
assert(MI->getOperand(OpNo).isReg());
O << "0(";
printOperand(MI, OpNo, O);
O << ")";
return false;
}
/// lookUpOrCreateTOCEntry -- Given a symbol, look up whether a TOC entry
/// exists for it. If not, create one. Then return a symbol that references
/// the TOC entry.
MCSymbol *PPCAsmPrinter::lookUpOrCreateTOCEntry(MCSymbol *Sym) {
const DataLayout *DL = TM.getDataLayout();
MCSymbol *&TOCEntry = TOC[Sym];
// To avoid name clash check if the name already exists.
while (!TOCEntry) {
if (OutContext.LookupSymbol(Twine(DL->getPrivateGlobalPrefix()) +
"C" + Twine(TOCLabelID++)) == nullptr) {
TOCEntry = GetTempSymbol("C", TOCLabelID);
}
}
return TOCEntry;
}
/// EmitInstruction -- Print out a single PowerPC MI in Darwin syntax to
/// the current output stream.
///
void PPCAsmPrinter::EmitInstruction(const MachineInstr *MI) {
MCInst TmpInst;
bool isPPC64 = Subtarget.isPPC64();
// Lower multi-instruction pseudo operations.
switch (MI->getOpcode()) {
default: break;
case TargetOpcode::DBG_VALUE:
llvm_unreachable("Should be handled target independently");
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'.
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BL)
// FIXME: We would like an efficient form for this, so we don't have to do
// a lot of extra uniquing.
.addExpr(MCSymbolRefExpr::Create(PICBase, OutContext)));
// Emit the label.
OutStreamer.EmitLabel(PICBase);
return;
}
case PPC::GetGBRO: {
// Get the offset from the GOT Base Register to the GOT
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
MCSymbol *PICOffset = MF->getInfo<PPCFunctionInfo>()->getPICOffsetSymbol();
TmpInst.setOpcode(PPC::LWZ);
const MCExpr *Exp =
MCSymbolRefExpr::Create(PICOffset, MCSymbolRefExpr::VK_None, OutContext);
const MCExpr *PB =
MCSymbolRefExpr::Create(MF->getPICBaseSymbol(),
MCSymbolRefExpr::VK_None,
OutContext);
const MCOperand MO = TmpInst.getOperand(1);
TmpInst.getOperand(1) = MCOperand::CreateExpr(MCBinaryExpr::CreateSub(Exp,
PB,
OutContext));
TmpInst.addOperand(MO);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::UpdateGBR: {
// Update the GOT Base Register to point to the GOT. It may be possible to
// merge this with the PPC::GetGBRO, doing it all in one step.
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
TmpInst.setOpcode(PPC::ADD4);
TmpInst.addOperand(TmpInst.getOperand(0));
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::LWZtoc: {
// Transform %X3 = LWZtoc <ga:@min1>, %X2
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to LWZ, and the global address operand to be a
// reference to the GOT entry we will synthesize later.
TmpInst.setOpcode(PPC::LWZ);
const MachineOperand &MO = MI->getOperand(1);
// Map symbol -> label of TOC entry
assert(MO.isGlobal() || MO.isCPI() || MO.isJTI());
MCSymbol *MOSymbol = nullptr;
if (MO.isGlobal())
MOSymbol = getSymbol(MO.getGlobal());
else if (MO.isCPI())
MOSymbol = GetCPISymbol(MO.getIndex());
else if (MO.isJTI())
MOSymbol = GetJTISymbol(MO.getIndex());
MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol);
const MCExpr *Exp =
MCSymbolRefExpr::Create(TOCEntry, MCSymbolRefExpr::VK_None,
OutContext);
const MCExpr *PB =
MCSymbolRefExpr::Create(OutContext.GetOrCreateSymbol(Twine(".L.TOC.")),
OutContext);
Exp = MCBinaryExpr::CreateSub(Exp, PB, OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::LDtocJTI:
case PPC::LDtocCPT:
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);
// Map symbol -> label of TOC entry
assert(MO.isGlobal() || MO.isCPI() || MO.isJTI());
MCSymbol *MOSymbol = nullptr;
if (MO.isGlobal())
MOSymbol = getSymbol(MO.getGlobal());
else if (MO.isCPI())
MOSymbol = GetCPISymbol(MO.getIndex());
else if (MO.isJTI())
MOSymbol = GetJTISymbol(MO.getIndex());
MCSymbol *TOCEntry = lookUpOrCreateTOCEntry(MOSymbol);
const MCExpr *Exp =
MCSymbolRefExpr::Create(TOCEntry, MCSymbolRefExpr::VK_PPC_TOC,
OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::ADDIStocHA: {
// Transform %Xd = ADDIStocHA %X2, <ga:@sym>
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to ADDIS8. If the global address is external, has
// common linkage, is a non-local function address, or is a jump table
// address, then generate a TOC entry and reference that. Otherwise
// reference the symbol directly.
TmpInst.setOpcode(PPC::ADDIS8);
const MachineOperand &MO = MI->getOperand(2);
assert((MO.isGlobal() || MO.isCPI() || MO.isJTI()) &&
"Invalid operand for ADDIStocHA!");
MCSymbol *MOSymbol = nullptr;
bool IsExternal = false;
bool IsNonLocalFunction = false;
bool IsCommon = false;
bool IsAvailExt = false;
if (MO.isGlobal()) {
const GlobalValue *GV = MO.getGlobal();
MOSymbol = getSymbol(GV);
IsExternal = GV->isDeclaration();
IsCommon = GV->hasCommonLinkage();
IsNonLocalFunction = GV->getType()->getElementType()->isFunctionTy() &&
(GV->isDeclaration() || GV->isWeakForLinker());
IsAvailExt = GV->hasAvailableExternallyLinkage();
} else if (MO.isCPI())
MOSymbol = GetCPISymbol(MO.getIndex());
else if (MO.isJTI())
MOSymbol = GetJTISymbol(MO.getIndex());
if (IsExternal || IsNonLocalFunction || IsCommon || IsAvailExt ||
MO.isJTI() || TM.getCodeModel() == CodeModel::Large)
MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
const MCExpr *Exp =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_HA,
OutContext);
TmpInst.getOperand(2) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::LDtocL: {
// Transform %Xd = LDtocL <ga:@sym>, %Xs
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to LD. If the global address is external, has
// common linkage, or is a jump table address, then reference the
// associated TOC entry. Otherwise reference the symbol directly.
TmpInst.setOpcode(PPC::LD);
const MachineOperand &MO = MI->getOperand(1);
assert((MO.isGlobal() || MO.isJTI() || MO.isCPI()) &&
"Invalid operand for LDtocL!");
MCSymbol *MOSymbol = nullptr;
if (MO.isJTI())
MOSymbol = lookUpOrCreateTOCEntry(GetJTISymbol(MO.getIndex()));
else if (MO.isCPI()) {
MOSymbol = GetCPISymbol(MO.getIndex());
if (TM.getCodeModel() == CodeModel::Large)
MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
}
else if (MO.isGlobal()) {
const GlobalValue *GValue = MO.getGlobal();
MOSymbol = getSymbol(GValue);
if (GValue->getType()->getElementType()->isFunctionTy() ||
GValue->isDeclaration() || GValue->hasCommonLinkage() ||
GValue->hasAvailableExternallyLinkage() ||
TM.getCodeModel() == CodeModel::Large)
MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
}
const MCExpr *Exp =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_LO,
OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::ADDItocL: {
// Transform %Xd = ADDItocL %Xs, <ga:@sym>
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to ADDI8. If the global address is external, then
// generate a TOC entry and reference that. Otherwise reference the
// symbol directly.
TmpInst.setOpcode(PPC::ADDI8);
const MachineOperand &MO = MI->getOperand(2);
assert((MO.isGlobal() || MO.isCPI()) && "Invalid operand for ADDItocL");
MCSymbol *MOSymbol = nullptr;
bool IsExternal = false;
bool IsNonLocalFunction = false;
if (MO.isGlobal()) {
const GlobalValue *GV = MO.getGlobal();
MOSymbol = getSymbol(GV);
IsExternal = GV->isDeclaration();
IsNonLocalFunction = GV->getType()->getElementType()->isFunctionTy() &&
(GV->isDeclaration() || GV->isWeakForLinker());
} else if (MO.isCPI())
MOSymbol = GetCPISymbol(MO.getIndex());
if (IsNonLocalFunction || IsExternal ||
TM.getCodeModel() == CodeModel::Large)
MOSymbol = lookUpOrCreateTOCEntry(MOSymbol);
const MCExpr *Exp =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_TOC_LO,
OutContext);
TmpInst.getOperand(2) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::ADDISgotTprelHA: {
// Transform: %Xd = ADDISgotTprelHA %X2, <ga:@sym>
// Into: %Xd = ADDIS8 %X2, sym@got@tlsgd@ha
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymGotTprel =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL_HA,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS8)
.addReg(MI->getOperand(0).getReg())
.addReg(PPC::X2)
.addExpr(SymGotTprel));
return;
}
case PPC::LDgotTprelL:
case PPC::LDgotTprelL32: {
// Transform %Xd = LDgotTprelL <ga:@sym>, %Xs
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to LD.
TmpInst.setOpcode(isPPC64 ? PPC::LD : PPC::LWZ);
const MachineOperand &MO = MI->getOperand(1);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *Exp =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL_LO,
OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
EmitToStreamer(OutStreamer, TmpInst);
return;
}
case PPC::PPC32GOT: {
MCSymbol *GOTSymbol = OutContext.GetOrCreateSymbol(StringRef("_GLOBAL_OFFSET_TABLE_"));
const MCExpr *SymGotTlsL =
MCSymbolRefExpr::Create(GOTSymbol, MCSymbolRefExpr::VK_PPC_LO,
OutContext);
const MCExpr *SymGotTlsHA =
MCSymbolRefExpr::Create(GOTSymbol, MCSymbolRefExpr::VK_PPC_HA,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::LI)
.addReg(MI->getOperand(0).getReg())
.addExpr(SymGotTlsL));
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS)
.addReg(MI->getOperand(0).getReg())
.addReg(MI->getOperand(0).getReg())
.addExpr(SymGotTlsHA));
return;
}
case PPC::ADDIStlsgdHA: {
// Transform: %Xd = ADDIStlsgdHA %X2, <ga:@sym>
// Into: %Xd = ADDIS8 %X2, sym@got@tlsgd@ha
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymGotTlsGD =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSGD_HA,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS8)
.addReg(MI->getOperand(0).getReg())
.addReg(PPC::X2)
.addExpr(SymGotTlsGD));
return;
}
case PPC::ADDItlsgdL: {
// Transform: %Xd = ADDItlsgdL %Xs, <ga:@sym>
// Into: %Xd = ADDI8 %Xs, sym@got@tlsgd@l
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymGotTlsGD =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSGD_LO,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDI8)
.addReg(MI->getOperand(0).getReg())
.addReg(MI->getOperand(1).getReg())
.addExpr(SymGotTlsGD));
return;
}
case PPC::GETtlsADDR: {
// Transform: %X3 = GETtlsADDR %X3, <ga:@sym>
// Into: BL8_NOP_TLS __tls_get_addr(sym@tlsgd)
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
StringRef Name = "__tls_get_addr";
MCSymbol *TlsGetAddr = OutContext.GetOrCreateSymbol(Name);
const MCSymbolRefExpr *TlsRef =
MCSymbolRefExpr::Create(TlsGetAddr, MCSymbolRefExpr::VK_None, OutContext);
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymVar =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_TLSGD,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BL8_NOP_TLS)
.addExpr(TlsRef)
.addExpr(SymVar));
return;
}
case PPC::ADDIStlsldHA: {
// Transform: %Xd = ADDIStlsldHA %X2, <ga:@sym>
// Into: %Xd = ADDIS8 %X2, sym@got@tlsld@ha
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymGotTlsLD =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSLD_HA,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS8)
.addReg(MI->getOperand(0).getReg())
.addReg(PPC::X2)
.addExpr(SymGotTlsLD));
return;
}
case PPC::ADDItlsldL: {
// Transform: %Xd = ADDItlsldL %Xs, <ga:@sym>
// Into: %Xd = ADDI8 %Xs, sym@got@tlsld@l
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymGotTlsLD =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TLSLD_LO,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDI8)
.addReg(MI->getOperand(0).getReg())
.addReg(MI->getOperand(1).getReg())
.addExpr(SymGotTlsLD));
return;
}
case PPC::GETtlsldADDR: {
// Transform: %X3 = GETtlsldADDR %X3, <ga:@sym>
// Into: BL8_NOP_TLS __tls_get_addr(sym@tlsld)
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
StringRef Name = "__tls_get_addr";
MCSymbol *TlsGetAddr = OutContext.GetOrCreateSymbol(Name);
const MCSymbolRefExpr *TlsRef =
MCSymbolRefExpr::Create(TlsGetAddr, MCSymbolRefExpr::VK_None, OutContext);
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymVar =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_TLSLD,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BL8_NOP_TLS)
.addExpr(TlsRef)
.addExpr(SymVar));
return;
}
case PPC::ADDISdtprelHA: {
// Transform: %Xd = ADDISdtprelHA %X3, <ga:@sym>
// Into: %Xd = ADDIS8 %X3, sym@dtprel@ha
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymDtprel =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_HA,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS8)
.addReg(MI->getOperand(0).getReg())
.addReg(PPC::X3)
.addExpr(SymDtprel));
return;
}
case PPC::ADDIdtprelL: {
// Transform: %Xd = ADDIdtprelL %Xs, <ga:@sym>
// Into: %Xd = ADDI8 %Xs, sym@dtprel@l
assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
const MachineOperand &MO = MI->getOperand(2);
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = getSymbol(GValue);
const MCExpr *SymDtprel =
MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_DTPREL_LO,
OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDI8)
.addReg(MI->getOperand(0).getReg())
.addReg(MI->getOperand(1).getReg())
.addExpr(SymDtprel));
return;
}
case PPC::MFOCRF:
case PPC::MFOCRF8:
if (!Subtarget.hasMFOCRF()) {
// Transform: %R3 = MFOCRF %CR7
// Into: %R3 = MFCR ;; cr7
unsigned NewOpcode =
MI->getOpcode() == PPC::MFOCRF ? PPC::MFCR : PPC::MFCR8;
OutStreamer.AddComment(PPCInstPrinter::
getRegisterName(MI->getOperand(1).getReg()));
EmitToStreamer(OutStreamer, MCInstBuilder(NewOpcode)
.addReg(MI->getOperand(0).getReg()));
return;
}
break;
case PPC::MTOCRF:
case PPC::MTOCRF8:
if (!Subtarget.hasMFOCRF()) {
// Transform: %CR7 = MTOCRF %R3
// Into: MTCRF mask, %R3 ;; cr7
unsigned NewOpcode =
MI->getOpcode() == PPC::MTOCRF ? PPC::MTCRF : PPC::MTCRF8;
unsigned Mask = 0x80 >> OutContext.getRegisterInfo()
->getEncodingValue(MI->getOperand(0).getReg());
OutStreamer.AddComment(PPCInstPrinter::
getRegisterName(MI->getOperand(0).getReg()));
EmitToStreamer(OutStreamer, MCInstBuilder(NewOpcode)
.addImm(Mask)
.addReg(MI->getOperand(1).getReg()));
return;
}
break;
case PPC::LD:
case PPC::STD:
case PPC::LWA_32:
case PPC::LWA: {
// Verify alignment is legal, so we don't create relocations
// that can't be supported.
// FIXME: This test is currently disabled for Darwin. The test
// suite shows a handful of test cases that fail this check for
// Darwin. Those need to be investigated before this sanity test
// can be enabled for those subtargets.
if (!Subtarget.isDarwin()) {
unsigned OpNum = (MI->getOpcode() == PPC::STD) ? 2 : 1;
const MachineOperand &MO = MI->getOperand(OpNum);
if (MO.isGlobal() && MO.getGlobal()->getAlignment() < 4)
llvm_unreachable("Global must be word-aligned for LD, STD, LWA!");
}
// Now process the instruction normally.
break;
}
}
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
EmitToStreamer(OutStreamer, TmpInst);
}
void PPCLinuxAsmPrinter::EmitStartOfAsmFile(Module &M) {
if (Subtarget.isELFv2ABI()) {
PPCTargetStreamer *TS =
static_cast<PPCTargetStreamer *>(OutStreamer.getTargetStreamer());
if (TS)
TS->emitAbiVersion(2);
}
if (Subtarget.isPPC64() || TM.getRelocationModel() != Reloc::PIC_)
return AsmPrinter::EmitStartOfAsmFile(M);
// FIXME: The use of .got2 assumes large GOT model (-fPIC), which is not
// optimal for some cases. We should consider supporting small model (-fpic)
// as well in the future.
assert(TM.getCodeModel() != CodeModel::Small &&
"Small code model PIC is currently unsupported.");
OutStreamer.SwitchSection(OutContext.getELFSection(".got2",
ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC,
SectionKind::getReadOnly()));
MCSymbol *TOCSym = OutContext.GetOrCreateSymbol(Twine(".L.TOC."));
MCSymbol *CurrentPos = OutContext.CreateTempSymbol();
OutStreamer.EmitLabel(CurrentPos);
// The GOT pointer points to the middle of the GOT, in order to reference the
// entire 64kB range. 0x8000 is the midpoint.
const MCExpr *tocExpr =
MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(CurrentPos, OutContext),
MCConstantExpr::Create(0x8000, OutContext),
OutContext);
OutStreamer.EmitAssignment(TOCSym, tocExpr);
OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
}
void PPCLinuxAsmPrinter::EmitFunctionEntryLabel() {
// linux/ppc32 - Normal entry label.
if (!Subtarget.isPPC64() && TM.getRelocationModel() != Reloc::PIC_)
return AsmPrinter::EmitFunctionEntryLabel();
if (!Subtarget.isPPC64()) {
const PPCFunctionInfo *PPCFI = MF->getInfo<PPCFunctionInfo>();
if (PPCFI->usesPICBase()) {
MCSymbol *RelocSymbol = PPCFI->getPICOffsetSymbol();
MCSymbol *PICBase = MF->getPICBaseSymbol();
OutStreamer.EmitLabel(RelocSymbol);
const MCExpr *OffsExpr =
MCBinaryExpr::CreateSub(
MCSymbolRefExpr::Create(OutContext.GetOrCreateSymbol(Twine(".L.TOC.")),
OutContext),
MCSymbolRefExpr::Create(PICBase, OutContext),
OutContext);
OutStreamer.EmitValue(OffsExpr, 4);
OutStreamer.EmitLabel(CurrentFnSym);
return;
} else
return AsmPrinter::EmitFunctionEntryLabel();
}
// ELFv2 ABI - Normal entry label.
if (Subtarget.isELFv2ABI())
return AsmPrinter::EmitFunctionEntryLabel();
// Emit an official procedure descriptor.
MCSectionSubPair Current = OutStreamer.getCurrentSection();
const MCSectionELF *Section = OutStreamer.getContext().getELFSection(".opd",
ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC,
SectionKind::getReadOnly());
OutStreamer.SwitchSection(Section);
OutStreamer.EmitLabel(CurrentFnSym);
OutStreamer.EmitValueToAlignment(8);
MCSymbol *Symbol1 =
OutContext.GetOrCreateSymbol(".L." + Twine(CurrentFnSym->getName()));
// Generates a R_PPC64_ADDR64 (from FK_DATA_8) relocation for the function
// entry point.
OutStreamer.EmitValue(MCSymbolRefExpr::Create(Symbol1, OutContext),
8 /*size*/);
MCSymbol *Symbol2 = OutContext.GetOrCreateSymbol(StringRef(".TOC."));
// Generates a R_PPC64_TOC relocation for TOC base insertion.
OutStreamer.EmitValue(MCSymbolRefExpr::Create(Symbol2,
MCSymbolRefExpr::VK_PPC_TOCBASE, OutContext),
8/*size*/);
// Emit a null environment pointer.
OutStreamer.EmitIntValue(0, 8 /* size */);
OutStreamer.SwitchSection(Current.first, Current.second);
MCSymbol *RealFnSym = OutContext.GetOrCreateSymbol(
".L." + Twine(CurrentFnSym->getName()));
OutStreamer.EmitLabel(RealFnSym);
CurrentFnSymForSize = RealFnSym;
}
bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
const DataLayout *TD = TM.getDataLayout();
bool isPPC64 = TD->getPointerSizeInBits() == 64;
PPCTargetStreamer &TS =
static_cast<PPCTargetStreamer &>(*OutStreamer.getTargetStreamer());
if (!TOC.empty()) {
const MCSectionELF *Section;
if (isPPC64)
Section = OutStreamer.getContext().getELFSection(".toc",
ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC,
SectionKind::getReadOnly());
else
Section = OutStreamer.getContext().getELFSection(".got2",
ELF::SHT_PROGBITS, ELF::SHF_WRITE | ELF::SHF_ALLOC,
SectionKind::getReadOnly());
OutStreamer.SwitchSection(Section);
for (MapVector<MCSymbol*, MCSymbol*>::iterator I = TOC.begin(),
E = TOC.end(); I != E; ++I) {
OutStreamer.EmitLabel(I->second);
MCSymbol *S = OutContext.GetOrCreateSymbol(I->first->getName());
if (isPPC64)
TS.emitTCEntry(*S);
else
OutStreamer.EmitSymbolValue(S, 4);
}
}
MachineModuleInfoELF &MMIELF =
MMI->getObjFileInfo<MachineModuleInfoELF>();
MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
if (!Stubs.empty()) {
OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
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*/);
}
Stubs.clear();
OutStreamer.AddBlankLine();
}
return AsmPrinter::doFinalization(M);
}
/// EmitFunctionBodyStart - Emit a global entry point prefix for ELFv2.
void PPCLinuxAsmPrinter::EmitFunctionBodyStart() {
// In the ELFv2 ABI, in functions that use the TOC register, we need to
// provide two entry points. The ABI guarantees that when calling the
// local entry point, r2 is set up by the caller to contain the TOC base
// for this function, and when calling the global entry point, r12 is set
// up by the caller to hold the address of the global entry point. We
// thus emit a prefix sequence along the following lines:
//
// func:
// # global entry point
// addis r2,r12,(.TOC.-func)@ha
// addi r2,r2,(.TOC.-func)@l
// .localentry func, .-func
// # local entry point, followed by function body
//
// This ensures we have r2 set up correctly while executing the function
// body, no matter which entry point is called.
if (Subtarget.isELFv2ABI()
// Only do all that if the function uses r2 in the first place.
&& !MF->getRegInfo().use_empty(PPC::X2)) {
MCSymbol *GlobalEntryLabel = OutContext.CreateTempSymbol();
OutStreamer.EmitLabel(GlobalEntryLabel);
const MCSymbolRefExpr *GlobalEntryLabelExp =
MCSymbolRefExpr::Create(GlobalEntryLabel, OutContext);
MCSymbol *TOCSymbol = OutContext.GetOrCreateSymbol(StringRef(".TOC."));
const MCExpr *TOCDeltaExpr =
MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(TOCSymbol, OutContext),
GlobalEntryLabelExp, OutContext);
const MCExpr *TOCDeltaHi =
PPCMCExpr::CreateHa(TOCDeltaExpr, false, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS)
.addReg(PPC::X2)
.addReg(PPC::X12)
.addExpr(TOCDeltaHi));
const MCExpr *TOCDeltaLo =
PPCMCExpr::CreateLo(TOCDeltaExpr, false, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDI)
.addReg(PPC::X2)
.addReg(PPC::X2)
.addExpr(TOCDeltaLo));
MCSymbol *LocalEntryLabel = OutContext.CreateTempSymbol();
OutStreamer.EmitLabel(LocalEntryLabel);
const MCSymbolRefExpr *LocalEntryLabelExp =
MCSymbolRefExpr::Create(LocalEntryLabel, OutContext);
const MCExpr *LocalOffsetExp =
MCBinaryExpr::CreateSub(LocalEntryLabelExp,
GlobalEntryLabelExp, OutContext);
PPCTargetStreamer *TS =
static_cast<PPCTargetStreamer *>(OutStreamer.getTargetStreamer());
if (TS)
TS->emitLocalEntry(CurrentFnSym, LocalOffsetExp);
}
}
/// EmitFunctionBodyEnd - Print the traceback table before the .size
/// directive.
///
void PPCLinuxAsmPrinter::EmitFunctionBodyEnd() {
// Only the 64-bit target requires a traceback table. For now,
// we only emit the word of zeroes that GDB requires to find
// the end of the function, and zeroes for the eight-byte
// mandatory fields.
// FIXME: We should fill in the eight-byte mandatory fields as described in
// the PPC64 ELF ABI (this is a low-priority item because GDB does not
// currently make use of these fields).
if (Subtarget.isPPC64()) {
OutStreamer.EmitIntValue(0, 4/*size*/);
OutStreamer.EmitIntValue(0, 8/*size*/);
}
}
void PPCDarwinAsmPrinter::EmitStartOfAsmFile(Module &M) {
static const char *const CPUDirectives[] = {
"",
"ppc",
"ppc440",
"ppc601",
"ppc602",
"ppc603",
"ppc7400",
"ppc750",
"ppc970",
"ppcA2",
"ppce500mc",
"ppce5500",
"power3",
"power4",
"power5",
"power5x",
"power6",
"power6x",
"power7",
"ppc64",
"ppc64le"
};
unsigned Directive = Subtarget.getDarwinDirective();
if (Subtarget.hasMFOCRF() && 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_64)
Directive = PPC::DIR_64;
assert(Directive <= PPC::DIR_64 && "Directive out of range.");
assert(Directive < array_lengthof(CPUDirectives) &&
"CPUDirectives[] might not be up-to-date!");
PPCTargetStreamer &TStreamer =
*static_cast<PPCTargetStreamer *>(OutStreamer.getTargetStreamer());
TStreamer.emitMachine(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",
MachO::S_SYMBOL_STUBS |
MachO::S_ATTR_PURE_INSTRUCTIONS,
32, SectionKind::getText()));
} else if (TM.getRelocationModel() == Reloc::DynamicNoPIC) {
OutStreamer.SwitchSection(
OutContext.getMachOSection("__TEXT","__symbol_stub1",
MachO::S_SYMBOL_STUBS |
MachO::S_ATTR_PURE_INSTRUCTIONS,
16, SectionKind::getText()));
}
OutStreamer.SwitchSection(getObjFileLowering().getTextSection());
}
static MCSymbol *GetLazyPtr(MCSymbol *Sym, MCContext &Ctx) {
// Remove $stub suffix, add $lazy_ptr.
StringRef NoStub = Sym->getName().substr(0, Sym->getName().size()-5);
return Ctx.GetOrCreateSymbol(NoStub + "$lazy_ptr");
}
static MCSymbol *GetAnonSym(MCSymbol *Sym, MCContext &Ctx) {
// Add $tmp suffix to $stub, yielding $stub$tmp.
return Ctx.GetOrCreateSymbol(Sym->getName() + "$tmp");
}
void PPCDarwinAsmPrinter::
EmitFunctionStubs(const MachineModuleInfoMachO::SymbolListTy &Stubs) {
bool isPPC64 = TM.getDataLayout()->getPointerSizeInBits() == 64;
bool isDarwin = Subtarget.isDarwin();
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",
MachO::S_SYMBOL_STUBS |
MachO::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);
const MCExpr *Anon = MCSymbolRefExpr::Create(AnonSymbol, OutContext);
const MCExpr *LazyPtrExpr = MCSymbolRefExpr::Create(LazyPtr, OutContext);
const MCExpr *Sub =
MCBinaryExpr::CreateSub(LazyPtrExpr, Anon, OutContext);
// mflr r0
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MFLR).addReg(PPC::R0));
// bcl 20, 31, AnonSymbol
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BCLalways).addExpr(Anon));
OutStreamer.EmitLabel(AnonSymbol);
// mflr r11
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MFLR).addReg(PPC::R11));
// addis r11, r11, ha16(LazyPtr - AnonSymbol)
const MCExpr *SubHa16 = PPCMCExpr::CreateHa(Sub, isDarwin, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::ADDIS)
.addReg(PPC::R11)
.addReg(PPC::R11)
.addExpr(SubHa16));
// mtlr r0
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MTLR).addReg(PPC::R0));
// ldu r12, lo16(LazyPtr - AnonSymbol)(r11)
// lwzu r12, lo16(LazyPtr - AnonSymbol)(r11)
const MCExpr *SubLo16 = PPCMCExpr::CreateLo(Sub, isDarwin, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(isPPC64 ? PPC::LDU : PPC::LWZU)
.addReg(PPC::R12)
.addExpr(SubLo16).addExpr(SubLo16)
.addReg(PPC::R11));
// mtctr r12
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MTCTR).addReg(PPC::R12));
// bctr
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BCTR));
OutStreamer.SwitchSection(LSPSection);
OutStreamer.EmitLabel(LazyPtr);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
MCSymbol *DyldStubBindingHelper =
OutContext.GetOrCreateSymbol(StringRef("dyld_stub_binding_helper"));
if (isPPC64) {
// .quad dyld_stub_binding_helper
OutStreamer.EmitSymbolValue(DyldStubBindingHelper, 8);
} else {
// .long dyld_stub_binding_helper
OutStreamer.EmitSymbolValue(DyldStubBindingHelper, 4);
}
}
OutStreamer.AddBlankLine();
return;
}
const MCSection *StubSection =
OutContext.getMachOSection("__TEXT","__symbol_stub1",
MachO::S_SYMBOL_STUBS |
MachO::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);
const MCExpr *LazyPtrExpr = MCSymbolRefExpr::Create(LazyPtr, OutContext);
OutStreamer.SwitchSection(StubSection);
EmitAlignment(4);
OutStreamer.EmitLabel(Stub);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
// lis r11, ha16(LazyPtr)
const MCExpr *LazyPtrHa16 =
PPCMCExpr::CreateHa(LazyPtrExpr, isDarwin, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::LIS)
.addReg(PPC::R11)
.addExpr(LazyPtrHa16));
// ldu r12, lo16(LazyPtr)(r11)
// lwzu r12, lo16(LazyPtr)(r11)
const MCExpr *LazyPtrLo16 =
PPCMCExpr::CreateLo(LazyPtrExpr, isDarwin, OutContext);
EmitToStreamer(OutStreamer, MCInstBuilder(isPPC64 ? PPC::LDU : PPC::LWZU)
.addReg(PPC::R12)
.addExpr(LazyPtrLo16).addExpr(LazyPtrLo16)
.addReg(PPC::R11));
// mtctr r12
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::MTCTR).addReg(PPC::R12));
// bctr
EmitToStreamer(OutStreamer, MCInstBuilder(PPC::BCTR));
OutStreamer.SwitchSection(LSPSection);
OutStreamer.EmitLabel(LazyPtr);
OutStreamer.EmitSymbolAttribute(RawSym, MCSA_IndirectSymbol);
MCSymbol *DyldStubBindingHelper =
OutContext.GetOrCreateSymbol(StringRef("dyld_stub_binding_helper"));
if (isPPC64) {
// .quad dyld_stub_binding_helper
OutStreamer.EmitSymbolValue(DyldStubBindingHelper, 8);
} else {
// .long dyld_stub_binding_helper
OutStreamer.EmitSymbolValue(DyldStubBindingHelper, 4);
}
}
OutStreamer.AddBlankLine();
}
bool PPCDarwinAsmPrinter::doFinalization(Module &M) {
bool isPPC64 = TM.getDataLayout()->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(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$stub:
OutStreamer.EmitLabel(Stubs[i].first);
// .indirect_symbol _foo
MachineModuleInfoImpl::StubValueTy &MCSym = Stubs[i].second;
OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol);
if (MCSym.getInt())
// External to current translation unit.
OutStreamer.EmitIntValue(0, isPPC64 ? 8 : 4/*size*/);
else
// Internal to current translation unit.
//
// When we place the LSDA into the TEXT section, the type info pointers
// need to be indirect and pc-rel. We accomplish this by using NLPs.
// However, sometimes the types are local to the file. So we need to
// fill in the value for the NLP in those cases.
OutStreamer.EmitValue(MCSymbolRefExpr::Create(MCSym.getPointer(),
OutContext),
isPPC64 ? 8 : 4/*size*/);
}
Stubs.clear();
OutStreamer.AddBlankLine();
}
Stubs = MMIMacho.GetHiddenGVStubList();
if (!Stubs.empty()) {
OutStreamer.SwitchSection(getObjFileLowering().getDataSection());
EmitAlignment(isPPC64 ? 3 : 2);
for (unsigned i = 0, e = Stubs.size(); i != e; ++i) {
// L_foo$stub:
OutStreamer.EmitLabel(Stubs[i].first);
// .long _foo
OutStreamer.EmitValue(MCSymbolRefExpr::
Create(Stubs[i].second.getPointer(),
OutContext),
isPPC64 ? 8 : 4/*size*/);
}
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);
TargetRegistry::RegisterAsmPrinter(ThePPC64LETarget, createPPCAsmPrinterPass);
}