llvm-for-llvmta/lib/Target/AVR/AVRMCInstLower.cpp

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3.6 KiB
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//===-- AVRMCInstLower.cpp - Convert AVR 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 AVR MachineInstrs to their corresponding
// MCInst records.
//
//===----------------------------------------------------------------------===//
#include "AVRMCInstLower.h"
#include "AVRInstrInfo.h"
#include "MCTargetDesc/AVRMCExpr.h"
#include "llvm/CodeGen/AsmPrinter.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/ErrorHandling.h"
namespace llvm {
MCOperand AVRMCInstLower::lowerSymbolOperand(const MachineOperand &MO,
MCSymbol *Sym) const {
unsigned char TF = MO.getTargetFlags();
const MCExpr *Expr = MCSymbolRefExpr::create(Sym, Ctx);
bool IsNegated = false;
if (TF & AVRII::MO_NEG) { IsNegated = true; }
if (!MO.isJTI() && MO.getOffset()) {
Expr = MCBinaryExpr::createAdd(
Expr, MCConstantExpr::create(MO.getOffset(), Ctx), Ctx);
}
bool IsFunction = MO.isGlobal() && isa<Function>(MO.getGlobal());
if (TF & AVRII::MO_LO) {
if (IsFunction) {
// N.B. Should we use _GS fixups here to cope with >128k progmem?
Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_PM_LO8, Expr, IsNegated, Ctx);
} else {
Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_LO8, Expr, IsNegated, Ctx);
}
} else if (TF & AVRII::MO_HI) {
if (IsFunction) {
// N.B. Should we use _GS fixups here to cope with >128k progmem?
Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_PM_HI8, Expr, IsNegated, Ctx);
} else {
Expr = AVRMCExpr::create(AVRMCExpr::VK_AVR_HI8, Expr, IsNegated, Ctx);
}
} else if (TF != 0) {
llvm_unreachable("Unknown target flag on symbol operand");
}
return MCOperand::createExpr(Expr);
}
void AVRMCInstLower::lowerInstruction(const MachineInstr &MI, MCInst &OutMI) const {
OutMI.setOpcode(MI.getOpcode());
for (MachineOperand const &MO : MI.operands()) {
MCOperand MCOp;
switch (MO.getType()) {
default:
MI.print(errs());
llvm_unreachable("unknown operand type");
case MachineOperand::MO_Register:
// Ignore all implicit register operands.
if (MO.isImplicit())
continue;
MCOp = MCOperand::createReg(MO.getReg());
break;
case MachineOperand::MO_Immediate:
MCOp = MCOperand::createImm(MO.getImm());
break;
case MachineOperand::MO_GlobalAddress:
MCOp = lowerSymbolOperand(MO, Printer.getSymbol(MO.getGlobal()));
break;
case MachineOperand::MO_ExternalSymbol:
MCOp = lowerSymbolOperand(
MO, Printer.GetExternalSymbolSymbol(MO.getSymbolName()));
break;
case MachineOperand::MO_MachineBasicBlock:
MCOp = MCOperand::createExpr(
MCSymbolRefExpr::create(MO.getMBB()->getSymbol(), Ctx));
break;
case MachineOperand::MO_RegisterMask:
continue;
case MachineOperand::MO_BlockAddress:
MCOp = lowerSymbolOperand(
MO, Printer.GetBlockAddressSymbol(MO.getBlockAddress()));
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;
}
OutMI.addOperand(MCOp);
}
}
} // end of namespace llvm