llvm-6502/lib/Target/PowerPC/PPCMCInstLower.cpp

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//===-- PPCMCInstLower.cpp - Convert PPC MachineInstr to an MCInst --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains code to lower PPC MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//
#include "PPC.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineModuleInfoImpls.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Target/Mangler.h"
#include "llvm/ADT/SmallString.h"
using namespace llvm;
static MachineModuleInfoMachO &getMachOMMI(AsmPrinter &AP) {
return AP.MMI->getObjFileInfo<MachineModuleInfoMachO>();
}
static MCSymbol *GetSymbolFromOperand(const MachineOperand &MO, AsmPrinter &AP){
MCContext &Ctx = AP.OutContext;
SmallString<128> Name;
if (!MO.isGlobal()) {
assert(MO.isSymbol() && "Isn't a symbol reference");
Name += AP.MAI->getGlobalPrefix();
Name += MO.getSymbolName();
} else {
const GlobalValue *GV = MO.getGlobal();
bool isImplicitlyPrivate = false;
if (MO.getTargetFlags() == PPCII::MO_DARWIN_STUB ||
(MO.getTargetFlags() & PPCII::MO_NLP_FLAG))
isImplicitlyPrivate = true;
AP.Mang->getNameWithPrefix(Name, GV, isImplicitlyPrivate);
}
// If the target flags on the operand changes the name of the symbol, do that
// before we return the symbol.
if (MO.getTargetFlags() == PPCII::MO_DARWIN_STUB) {
Name += "$stub";
MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
MachineModuleInfoImpl::StubValueTy &StubSym =
getMachOMMI(AP).getFnStubEntry(Sym);
if (StubSym.getPointer())
return Sym;
if (MO.isGlobal()) {
StubSym =
MachineModuleInfoImpl::
StubValueTy(AP.Mang->getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
} else {
Name.erase(Name.end()-5, Name.end());
StubSym =
MachineModuleInfoImpl::
StubValueTy(Ctx.GetOrCreateSymbol(Name.str()), false);
}
return Sym;
}
// If the symbol reference is actually to a non_lazy_ptr, not to the symbol,
// then add the suffix.
if (MO.getTargetFlags() & PPCII::MO_NLP_FLAG) {
Name += "$non_lazy_ptr";
MCSymbol *Sym = Ctx.GetOrCreateSymbol(Name.str());
MachineModuleInfoMachO &MachO = getMachOMMI(AP);
MachineModuleInfoImpl::StubValueTy &StubSym =
(MO.getTargetFlags() & PPCII::MO_NLP_HIDDEN_FLAG) ?
MachO.getHiddenGVStubEntry(Sym) : MachO.getGVStubEntry(Sym);
if (StubSym.getPointer() == 0) {
assert(MO.isGlobal() && "Extern symbol not handled yet");
StubSym = MachineModuleInfoImpl::
StubValueTy(AP.Mang->getSymbol(MO.getGlobal()),
!MO.getGlobal()->hasInternalLinkage());
}
return Sym;
}
return Ctx.GetOrCreateSymbol(Name.str());
}
static MCOperand GetSymbolRef(const MachineOperand &MO, const MCSymbol *Symbol,
AsmPrinter &Printer) {
MCContext &Ctx = Printer.OutContext;
MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
if (MO.getTargetFlags() & PPCII::MO_LO16)
RefKind = MCSymbolRefExpr::VK_PPC_LO16;
else if (MO.getTargetFlags() & PPCII::MO_HA16)
RefKind = MCSymbolRefExpr::VK_PPC_HA16;
// FIXME: This isn't right, but we don't have a good way to express this in
// the MC Level, see below.
if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG)
RefKind = MCSymbolRefExpr::VK_None;
const MCExpr *Expr = MCSymbolRefExpr::Create(Symbol, RefKind, Ctx);
if (!MO.isJTI() && MO.getOffset())
Expr = MCBinaryExpr::CreateAdd(Expr,
MCConstantExpr::Create(MO.getOffset(), Ctx),
Ctx);
// Subtract off the PIC base if required.
if (MO.getTargetFlags() & PPCII::MO_PIC_FLAG) {
const MachineFunction *MF = MO.getParent()->getParent()->getParent();
const MCExpr *PB = MCSymbolRefExpr::Create(MF->getPICBaseSymbol(), Ctx);
Expr = MCBinaryExpr::CreateSub(Expr, PB, Ctx);
// FIXME: We have no way to make the result be VK_PPC_LO16/VK_PPC_HA16,
// since it is not a symbol!
}
return MCOperand::CreateExpr(Expr);
}
void llvm::LowerPPCMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
AsmPrinter &AP) {
OutMI.setOpcode(MI->getOpcode());
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
MCOperand MCOp;
switch (MO.getType()) {
default:
MI->dump();
assert(0 && "unknown operand type");
case MachineOperand::MO_Register:
assert(!MO.getSubReg() && "Subregs should be eliminated!");
MCOp = MCOperand::CreateReg(MO.getReg());
break;
case MachineOperand::MO_Immediate:
MCOp = MCOperand::CreateImm(MO.getImm());
break;
case MachineOperand::MO_MachineBasicBlock:
MCOp = MCOperand::CreateExpr(MCSymbolRefExpr::Create(
MO.getMBB()->getSymbol(), AP.OutContext));
break;
case MachineOperand::MO_GlobalAddress:
case MachineOperand::MO_ExternalSymbol:
MCOp = GetSymbolRef(MO, GetSymbolFromOperand(MO, AP), AP);
break;
case MachineOperand::MO_JumpTableIndex:
MCOp = GetSymbolRef(MO, AP.GetJTISymbol(MO.getIndex()), AP);
break;
case MachineOperand::MO_ConstantPoolIndex:
MCOp = GetSymbolRef(MO, AP.GetCPISymbol(MO.getIndex()), AP);
break;
case MachineOperand::MO_BlockAddress:
MCOp = GetSymbolRef(MO,AP.GetBlockAddressSymbol(MO.getBlockAddress()),AP);
break;
}
OutMI.addOperand(MCOp);
}
}