llvm-project/llvm/lib/Target/RISCV/RISCVMCInstLower.cpp

117 lines
3.7 KiB
C++

//===-- RISCVMCInstLower.cpp - Convert RISCV MachineInstr to an MCInst ------=//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// This file contains code to lower RISCV MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//
#include "RISCV.h"
#include "MCTargetDesc/RISCVMCExpr.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
static MCOperand lowerSymbolOperand(const MachineOperand &MO, MCSymbol *Sym,
const AsmPrinter &AP) {
MCContext &Ctx = AP.OutContext;
RISCVMCExpr::VariantKind Kind;
switch (MO.getTargetFlags()) {
default:
llvm_unreachable("Unknown target flag on GV operand");
case RISCVII::MO_None:
Kind = RISCVMCExpr::VK_RISCV_None;
break;
case RISCVII::MO_CALL:
Kind = RISCVMCExpr::VK_RISCV_CALL;
break;
case RISCVII::MO_LO:
Kind = RISCVMCExpr::VK_RISCV_LO;
break;
case RISCVII::MO_HI:
Kind = RISCVMCExpr::VK_RISCV_HI;
break;
case RISCVII::MO_PCREL_LO:
Kind = RISCVMCExpr::VK_RISCV_PCREL_LO;
break;
case RISCVII::MO_PCREL_HI:
Kind = RISCVMCExpr::VK_RISCV_PCREL_HI;
break;
}
const MCExpr *ME =
MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, Ctx);
if (!MO.isJTI() && !MO.isMBB() && MO.getOffset())
ME = MCBinaryExpr::createAdd(
ME, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
if (Kind != RISCVMCExpr::VK_RISCV_None)
ME = RISCVMCExpr::create(ME, Kind, Ctx);
return MCOperand::createExpr(ME);
}
bool llvm::LowerRISCVMachineOperandToMCOperand(const MachineOperand &MO,
MCOperand &MCOp,
const AsmPrinter &AP) {
switch (MO.getType()) {
default:
report_fatal_error("LowerRISCVMachineInstrToMCInst: 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 = lowerSymbolOperand(MO, MO.getMBB()->getSymbol(), AP);
break;
case MachineOperand::MO_GlobalAddress:
MCOp = lowerSymbolOperand(MO, AP.getSymbol(MO.getGlobal()), AP);
break;
case MachineOperand::MO_BlockAddress:
MCOp = lowerSymbolOperand(
MO, AP.GetBlockAddressSymbol(MO.getBlockAddress()), AP);
break;
case MachineOperand::MO_ExternalSymbol:
MCOp = lowerSymbolOperand(
MO, AP.GetExternalSymbolSymbol(MO.getSymbolName()), AP);
break;
case MachineOperand::MO_ConstantPoolIndex:
MCOp = lowerSymbolOperand(MO, AP.GetCPISymbol(MO.getIndex()), AP);
break;
}
return true;
}
void llvm::LowerRISCVMachineInstrToMCInst(const MachineInstr *MI, MCInst &OutMI,
const AsmPrinter &AP) {
OutMI.setOpcode(MI->getOpcode());
for (const MachineOperand &MO : MI->operands()) {
MCOperand MCOp;
if (LowerRISCVMachineOperandToMCOperand(MO, MCOp, AP))
OutMI.addOperand(MCOp);
}
}