164 lines · cpp
1//===-- M68kInstPrinter.cpp - Convert M68k MCInst to asm --------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8///9/// \file10/// This file contains definitions for an M68k MCInst printer.11///12//===----------------------------------------------------------------------===//13 14// TODO Conform with all supported Motorola ASM syntax15// Motorola's assembly has several syntax variants, especially on16// addressing modes.17// For example, you can write pc indirect w/ displacement as18// `x(%pc)`, where `x` is the displacement imm, or `(x,%pc)`.19// Currently we're picking the variant that is different from20// GCC, albeit being recognizable by GNU AS.21// Not sure what is the impact now (e.g. some syntax might22// not be recognized by some old consoles' toolchains, in which23// case we can not use our integrated assembler), but either way,24// it will be great to support all of the variants in the future.25 26#include "M68kInstPrinter.h"27#include "M68kBaseInfo.h"28 29#include "llvm/ADT/StringExtras.h"30#include "llvm/MC/MCAsmInfo.h"31#include "llvm/MC/MCExpr.h"32#include "llvm/MC/MCInst.h"33#include "llvm/MC/MCInstrInfo.h"34#include "llvm/MC/MCSymbol.h"35#include "llvm/Support/ErrorHandling.h"36#include "llvm/Support/raw_ostream.h"37 38using namespace llvm;39 40#define DEBUG_TYPE "asm-printer"41 42#define PRINT_ALIAS_INSTR43#include "M68kGenAsmWriter.inc"44 45void M68kInstPrinter::printRegName(raw_ostream &OS, MCRegister Reg) {46 OS << "%" << getRegisterName(Reg);47}48 49void M68kInstPrinter::printInst(const MCInst *MI, uint64_t Address,50 StringRef Annot, const MCSubtargetInfo &STI,51 raw_ostream &O) {52 if (!printAliasInstr(MI, Address, O))53 printInstruction(MI, Address, O);54 55 printAnnotation(O, Annot);56}57 58void M68kInstPrinter::printOperand(const MCInst *MI, unsigned OpNo,59 raw_ostream &O) {60 const MCOperand &MO = MI->getOperand(OpNo);61 if (MO.isReg()) {62 printRegName(O, MO.getReg());63 return;64 }65 66 if (MO.isImm()) {67 printImmediate(MI, OpNo, O);68 return;69 }70 71 assert(MO.isExpr() && "Unknown operand kind in printOperand");72 MAI.printExpr(O, *MO.getExpr());73}74 75void M68kInstPrinter::printImmediate(const MCInst *MI, unsigned opNum,76 raw_ostream &O) {77 const MCOperand &MO = MI->getOperand(opNum);78 if (MO.isImm())79 O << '#' << MO.getImm();80 else if (MO.isExpr()) {81 O << '#';82 MAI.printExpr(O, *MO.getExpr());83 } else84 llvm_unreachable("Unknown immediate kind");85}86 87void M68kInstPrinter::printMoveMask(const MCInst *MI, unsigned opNum,88 raw_ostream &O) {89 unsigned Mask = MI->getOperand(opNum).getImm();90 assert((Mask & 0xFFFF) == Mask && "Mask is always 16 bits");91 92 // A move mask is splitted into two parts:93 // bits 0 ~ 7 correspond to D0 ~ D7 regs94 // bits 8 ~ 15 correspond to A0 ~ A7 regs95 //96 // In the assembly syntax, we want to use a dash to replace97 // a continuous range of registers. For example, if the bit98 // mask is 0b101110, we want to print "D1-D3,D5" instead of99 // "D1,D2,D3,D4,D5".100 //101 // However, we don't want a dash to cross between data registers102 // and address registers (i.e. there shouldn't be a dash crossing103 // bit 7 and 8) since that is not really intuitive. So we simply104 // print the data register part (bit 0~7) and address register part105 // separately.106 uint8_t HalfMask;107 unsigned Reg;108 for (int s = 0; s < 16; s += 8) {109 HalfMask = (Mask >> s) & 0xFF;110 // Print separation comma only if111 // both data & register parts have bit(s) set112 if (s != 0 && (Mask & 0xFF) && HalfMask)113 O << '/';114 115 for (int i = 0; HalfMask; ++i) {116 if ((HalfMask >> i) & 0b1) {117 HalfMask ^= 0b1 << i;118 Reg = M68kII::getMaskedSpillRegister(i + s);119 printRegName(O, Reg);120 121 int j = i;122 while ((HalfMask >> (j + 1)) & 0b1)123 HalfMask ^= 0b1 << ++j;124 125 if (j != i) {126 O << '-';127 Reg = M68kII::getMaskedSpillRegister(j + s);128 printRegName(O, Reg);129 }130 131 i = j;132 133 if (HalfMask)134 O << '/';135 }136 }137 }138}139 140void M68kInstPrinter::printDisp(const MCInst *MI, unsigned opNum,141 raw_ostream &O) {142 const MCOperand &Op = MI->getOperand(opNum);143 if (Op.isImm()) {144 O << Op.getImm();145 return;146 }147 assert(Op.isExpr() && "Unknown operand kind in printOperand");148 MAI.printExpr(O, *Op.getExpr());149}150 151// NOTE forcing (W,L) size available since M68020 only152void M68kInstPrinter::printAbsMem(const MCInst *MI, unsigned opNum,153 raw_ostream &O) {154 const MCOperand &MO = MI->getOperand(opNum);155 156 if (MO.isExpr()) {157 MAI.printExpr(O, *MO.getExpr());158 return;159 }160 161 assert(MO.isImm() && "absolute memory addressing needs an immediate");162 O << format("$%0" PRIx64, (uint64_t)MO.getImm());163}164