//==-- AArch64MCInstLower.cpp - Convert AArch64 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 AArch64 MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//
#include "AArch64MCInstLower.h"
#include "MCTargetDesc/AArch64MCExpr.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
AArch64MCInstLower::AArch64MCInstLower(MCContext &ctx, Mangler &mang,
AsmPrinter &printer)
: Ctx(ctx), Printer(printer), TargetTriple(printer.getTargetTriple()) {}
MCSymbol *
AArch64MCInstLower::GetGlobalAddressSymbol(const MachineOperand &MO) const {
return Printer.getSymbol(MO.getGlobal());
}
MCSymbol *
AArch64MCInstLower::GetExternalSymbolSymbol(const MachineOperand &MO) const {
return Printer.GetExternalSymbolSymbol(MO.getSymbolName());
}
MCOperand AArch64MCInstLower::lowerSymbolOperandDarwin(const MachineOperand &MO,
MCSymbol *Sym) const {
// FIXME: We would like an efficient form for this, so we don't have to do a
// lot of extra uniquing.
MCSymbolRefExpr::VariantKind RefKind = MCSymbolRefExpr::VK_None;
if ((MO.getTargetFlags() & AArch64II::MO_GOT) != 0) {
if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
RefKind = MCSymbolRefExpr::VK_GOTPAGE;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
AArch64II::MO_PAGEOFF)
RefKind = MCSymbolRefExpr::VK_GOTPAGEOFF;
else
llvm_unreachable("Unexpected target flags with MO_GOT on GV operand");
} else if ((MO.getTargetFlags() & AArch64II::MO_TLS) != 0) {
if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
RefKind = MCSymbolRefExpr::VK_TLVPPAGE;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
AArch64II::MO_PAGEOFF)
RefKind = MCSymbolRefExpr::VK_TLVPPAGEOFF;
else
llvm_unreachable("Unexpected target flags with MO_TLS on GV operand");
} else {
if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
RefKind = MCSymbolRefExpr::VK_PAGE;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
AArch64II::MO_PAGEOFF)
RefKind = MCSymbolRefExpr::VK_PAGEOFF;
}
const MCExpr *Expr = MCSymbolRefExpr::Create(Sym, RefKind, Ctx);
if (!MO.isJTI() && MO.getOffset())
Expr = MCBinaryExpr::CreateAdd(
Expr, MCConstantExpr::Create(MO.getOffset(), Ctx), Ctx);
return MCOperand::CreateExpr(Expr);
}
MCOperand AArch64MCInstLower::lowerSymbolOperandELF(const MachineOperand &MO,
MCSymbol *Sym) const {
uint32_t RefFlags = 0;
if (MO.getTargetFlags() & AArch64II::MO_GOT)
RefFlags |= AArch64MCExpr::VK_GOT;
else if (MO.getTargetFlags() & AArch64II::MO_TLS) {
TLSModel::Model Model;
if (MO.isGlobal()) {
const GlobalValue *GV = MO.getGlobal();
Model = Printer.TM.getTLSModel(GV);
} else {
assert(MO.isSymbol() &&
StringRef(MO.getSymbolName()) == "_TLS_MODULE_BASE_" &&
"unexpected external TLS symbol");
Model = TLSModel::GeneralDynamic;
}
switch (Model) {
case TLSModel::InitialExec:
RefFlags |= AArch64MCExpr::VK_GOTTPREL;
break;
case TLSModel::LocalExec:
RefFlags |= AArch64MCExpr::VK_TPREL;
break;
case TLSModel::LocalDynamic:
RefFlags |= AArch64MCExpr::VK_DTPREL;
break;
case TLSModel::GeneralDynamic:
RefFlags |= AArch64MCExpr::VK_TLSDESC;
break;
}
} else {
// No modifier means this is a generic reference, classified as absolute for
// the cases where it matters (:abs_g0: etc).
RefFlags |= AArch64MCExpr::VK_ABS;
}
if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_PAGE)
RefFlags |= AArch64MCExpr::VK_PAGE;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) ==
AArch64II::MO_PAGEOFF)
RefFlags |= AArch64MCExpr::VK_PAGEOFF;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G3)
RefFlags |= AArch64MCExpr::VK_G3;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G2)
RefFlags |= AArch64MCExpr::VK_G2;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G1)
RefFlags |= AArch64MCExpr::VK_G1;
else if ((MO.getTargetFlags() & AArch64II::MO_FRAGMENT) == AArch64II::MO_G0)
RefFlags |= AArch64MCExpr::VK_G0;
if (MO.getTargetFlags() & AArch64II::MO_NC)
RefFlags |= AArch64MCExpr::VK_NC;
const MCExpr *Expr =
MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_None, Ctx);
if (!MO.isJTI() && MO.getOffset())
Expr = MCBinaryExpr::CreateAdd(
Expr, MCConstantExpr::Create(MO.getOffset(), Ctx), Ctx);
AArch64MCExpr::VariantKind RefKind;
RefKind = static_cast<AArch64MCExpr::VariantKind>(RefFlags);
Expr = AArch64MCExpr::Create(Expr, RefKind, Ctx);
return MCOperand::CreateExpr(Expr);
}
MCOperand AArch64MCInstLower::LowerSymbolOperand(const MachineOperand &MO,
MCSymbol *Sym) const {
if (TargetTriple.isOSDarwin())
return lowerSymbolOperandDarwin(MO, Sym);
assert(TargetTriple.isOSBinFormatELF() && "Expect Darwin or ELF target");
return lowerSymbolOperandELF(MO, Sym);
}
bool AArch64MCInstLower::lowerOperand(const MachineOperand &MO,
MCOperand &MCOp) const {
switch (MO.getType()) {
default:
llvm_unreachable("unknown operand type");
case MachineOperand::MO_Register:
// Ignore all implicit register operands.
if (MO.isImplicit())
return false;
MCOp = MCOperand::CreateReg(MO.getReg());
break;
case MachineOperand::MO_RegisterMask:
// Regmasks are like implicit defs.
return false;
case MachineOperand::MO_Immediate:
MCOp = MCOperand::CreateImm(MO.getImm());
break;
case MachineOperand::MO_MachineBasicBlock:
MCOp = MCOperand::CreateExpr(
MCSymbolRefExpr::Create(MO.getMBB()->getSymbol(), Ctx));
break;
case MachineOperand::MO_GlobalAddress:
MCOp = LowerSymbolOperand(MO, GetGlobalAddressSymbol(MO));
break;
case MachineOperand::MO_ExternalSymbol:
MCOp = LowerSymbolOperand(MO, GetExternalSymbolSymbol(MO));
break;
case MachineOperand::MO_JumpTableIndex:
MCOp = LowerSymbolOperand(MO, Printer.GetJTISymbol(MO.getIndex()));
break;
case MachineOperand::MO_ConstantPoolIndex:
MCOp = LowerSymbolOperand(MO, Printer.GetCPISymbol(MO.getIndex()));
break;
case MachineOperand::MO_BlockAddress:
MCOp = LowerSymbolOperand(
MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()));
break;
}
return true;
}
void AArch64MCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
OutMI.setOpcode(MI->getOpcode());
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
MCOperand MCOp;
if (lowerOperand(MI->getOperand(i), MCOp))
OutMI.addOperand(MCOp);
}
}