llvm-for-llvmta/lib/Target/SystemZ/SystemZMCInstLower.cpp

103 lines
3.2 KiB
C++

//===-- SystemZMCInstLower.cpp - Lower MachineInstr to 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
//
//===----------------------------------------------------------------------===//
#include "SystemZMCInstLower.h"
#include "SystemZAsmPrinter.h"
#include "llvm/IR/Mangler.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCStreamer.h"
using namespace llvm;
// Return the VK_* enumeration for MachineOperand target flags Flags.
static MCSymbolRefExpr::VariantKind getVariantKind(unsigned Flags) {
switch (Flags & SystemZII::MO_SYMBOL_MODIFIER) {
case 0:
return MCSymbolRefExpr::VK_None;
case SystemZII::MO_GOT:
return MCSymbolRefExpr::VK_GOT;
case SystemZII::MO_INDNTPOFF:
return MCSymbolRefExpr::VK_INDNTPOFF;
}
llvm_unreachable("Unrecognised MO_ACCESS_MODEL");
}
SystemZMCInstLower::SystemZMCInstLower(MCContext &ctx,
SystemZAsmPrinter &asmprinter)
: Ctx(ctx), AsmPrinter(asmprinter) {}
const MCExpr *
SystemZMCInstLower::getExpr(const MachineOperand &MO,
MCSymbolRefExpr::VariantKind Kind) const {
const MCSymbol *Symbol;
bool HasOffset = true;
switch (MO.getType()) {
case MachineOperand::MO_MachineBasicBlock:
Symbol = MO.getMBB()->getSymbol();
HasOffset = false;
break;
case MachineOperand::MO_GlobalAddress:
Symbol = AsmPrinter.getSymbol(MO.getGlobal());
break;
case MachineOperand::MO_ExternalSymbol:
Symbol = AsmPrinter.GetExternalSymbolSymbol(MO.getSymbolName());
break;
case MachineOperand::MO_JumpTableIndex:
Symbol = AsmPrinter.GetJTISymbol(MO.getIndex());
HasOffset = false;
break;
case MachineOperand::MO_ConstantPoolIndex:
Symbol = AsmPrinter.GetCPISymbol(MO.getIndex());
break;
case MachineOperand::MO_BlockAddress:
Symbol = AsmPrinter.GetBlockAddressSymbol(MO.getBlockAddress());
break;
default:
llvm_unreachable("unknown operand type");
}
const MCExpr *Expr = MCSymbolRefExpr::create(Symbol, Kind, Ctx);
if (HasOffset)
if (int64_t Offset = MO.getOffset()) {
const MCExpr *OffsetExpr = MCConstantExpr::create(Offset, Ctx);
Expr = MCBinaryExpr::createAdd(Expr, OffsetExpr, Ctx);
}
return Expr;
}
MCOperand SystemZMCInstLower::lowerOperand(const MachineOperand &MO) const {
switch (MO.getType()) {
case MachineOperand::MO_Register:
return MCOperand::createReg(MO.getReg());
case MachineOperand::MO_Immediate:
return MCOperand::createImm(MO.getImm());
default: {
MCSymbolRefExpr::VariantKind Kind = getVariantKind(MO.getTargetFlags());
return MCOperand::createExpr(getExpr(MO, Kind));
}
}
}
void SystemZMCInstLower::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);
// Ignore all implicit register operands.
if (!MO.isReg() || !MO.isImplicit())
OutMI.addOperand(lowerOperand(MO));
}
}