llvm-project/llvm/lib/Target/ARC/ARCMCInstLower.cpp

115 lines
3.7 KiB
C++

//===- ARCMCInstLower.cpp - ARC MachineInstr to MCInst ----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file contains code to lower ARC MachineInstrs to their
/// corresponding MCInst records.
///
//===----------------------------------------------------------------------===//
#include "ARCMCInstLower.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
using namespace llvm;
ARCMCInstLower::ARCMCInstLower(MCContext *C, AsmPrinter &AsmPrinter)
: Ctx(C), Printer(AsmPrinter) {}
MCOperand ARCMCInstLower::LowerSymbolOperand(const MachineOperand &MO,
MachineOperandType MOTy,
unsigned Offset) const {
MCSymbolRefExpr::VariantKind Kind = MCSymbolRefExpr::VK_None;
const MCSymbol *Symbol;
switch (MOTy) {
case MachineOperand::MO_MachineBasicBlock:
Symbol = MO.getMBB()->getSymbol();
break;
case MachineOperand::MO_GlobalAddress:
Symbol = Printer.getSymbol(MO.getGlobal());
Offset += MO.getOffset();
break;
case MachineOperand::MO_BlockAddress:
Symbol = Printer.GetBlockAddressSymbol(MO.getBlockAddress());
Offset += MO.getOffset();
break;
case MachineOperand::MO_ExternalSymbol:
Symbol = Printer.GetExternalSymbolSymbol(MO.getSymbolName());
Offset += MO.getOffset();
break;
case MachineOperand::MO_JumpTableIndex:
Symbol = Printer.GetJTISymbol(MO.getIndex());
break;
case MachineOperand::MO_ConstantPoolIndex:
Symbol = Printer.GetCPISymbol(MO.getIndex());
Offset += MO.getOffset();
break;
default:
llvm_unreachable("<unknown operand type>");
}
assert(Symbol && "Symbol creation failed.\n");
const MCSymbolRefExpr *MCSym = MCSymbolRefExpr::create(Symbol, Kind, *Ctx);
if (!Offset)
return MCOperand::createExpr(MCSym);
// Assume offset is never negative.
assert(Offset > 0);
const MCConstantExpr *OffsetExpr = MCConstantExpr::create(Offset, *Ctx);
const MCBinaryExpr *Add = MCBinaryExpr::createAdd(MCSym, OffsetExpr, *Ctx);
return MCOperand::createExpr(Add);
}
MCOperand ARCMCInstLower::LowerOperand(const MachineOperand &MO,
unsigned Offset) const {
MachineOperandType MOTy = MO.getType();
switch (MOTy) {
default:
llvm_unreachable("unknown operand type");
case MachineOperand::MO_Register:
// Ignore all implicit register operands.
if (MO.isImplicit())
break;
return MCOperand::createReg(MO.getReg());
case MachineOperand::MO_Immediate:
return MCOperand::createImm(MO.getImm() + Offset);
case MachineOperand::MO_MachineBasicBlock:
case MachineOperand::MO_GlobalAddress:
case MachineOperand::MO_ExternalSymbol:
case MachineOperand::MO_JumpTableIndex:
case MachineOperand::MO_ConstantPoolIndex:
case MachineOperand::MO_BlockAddress:
return LowerSymbolOperand(MO, MOTy, Offset);
case MachineOperand::MO_RegisterMask:
break;
}
return {};
}
void ARCMCInstLower::Lower(const MachineInstr *MI, MCInst &OutMI) const {
OutMI.setOpcode(MI->getOpcode());
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
MCOperand MCOp = LowerOperand(MO);
if (MCOp.isValid())
OutMI.addOperand(MCOp);
}
}