136 lines
4.7 KiB
C++
136 lines
4.7 KiB
C++
/*
|
|
* This file is part of the 65816 Emulator Library.
|
|
* Copyright (c) 2018 Francesco Rigoni.
|
|
*
|
|
* https://github.com/FrancescoRigoni/Lib65816
|
|
*
|
|
* This program is free software: you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation, version 3.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#include "../Cpu65816.hpp"
|
|
|
|
#define LOG_TAG "Cpu::executeROL"
|
|
|
|
#define DO_ROL_8_BIT(value) { \
|
|
bool carryWasSet = mCpuStatus.carryFlag(); \
|
|
bool carryWillBeSet = (value & 0x80) != 0; \
|
|
value = value << 1; \
|
|
if (carryWasSet) Binary::setBitIn8BitValue(&value, 0); \
|
|
else Binary::clearBitIn8BitValue(&value, 0); \
|
|
if (carryWillBeSet) mCpuStatus.setCarryFlag(); \
|
|
else mCpuStatus.clearCarryFlag(); \
|
|
mCpuStatus.updateSignAndZeroFlagFrom16BitValue(value); \
|
|
}
|
|
|
|
#define DO_ROL_16_BIT(value) { \
|
|
bool carryWasSet = mCpuStatus.carryFlag(); \
|
|
bool carryWillBeSet = (value & 0x8000) != 0; \
|
|
value = value << 1; \
|
|
if (carryWasSet) Binary::setBitIn16BitValue(&value, 0); \
|
|
else Binary::clearBitIn16BitValue(&value, 0); \
|
|
if (carryWillBeSet) mCpuStatus.setCarryFlag(); \
|
|
else mCpuStatus.clearCarryFlag(); \
|
|
mCpuStatus.updateSignAndZeroFlagFrom16BitValue(value); \
|
|
}
|
|
|
|
/**
|
|
* This file contains implementations for all ROL OpCodes.
|
|
*/
|
|
void Cpu65816::executeMemoryROL(OpCode &opCode) {
|
|
Address opCodeDataAddress = getAddressOfOpCodeData(opCode);
|
|
|
|
if(accumulatorIs8BitWide()) {
|
|
uint8_t value = mSystemBus.readByte(opCodeDataAddress);
|
|
DO_ROL_8_BIT(value);
|
|
mSystemBus.storeByte(opCodeDataAddress, value);
|
|
} else {
|
|
uint16_t value = mSystemBus.readTwoBytes(opCodeDataAddress);
|
|
DO_ROL_16_BIT(value);
|
|
mSystemBus.storeTwoBytes(opCodeDataAddress, value);
|
|
}
|
|
}
|
|
|
|
void Cpu65816::executeAccumulatorROL(OpCode &opCode) {
|
|
if(accumulatorIs8BitWide()) {
|
|
uint8_t value = Binary::lower8BitsOf(mA);
|
|
DO_ROL_8_BIT(value);
|
|
Binary::setLower8BitsOf16BitsValue(&mA, value);
|
|
} else {
|
|
uint16_t value = mA;
|
|
DO_ROL_16_BIT(value);
|
|
mA = value;
|
|
}
|
|
}
|
|
|
|
void Cpu65816::executeROL(OpCode &opCode) {
|
|
switch (opCode.getCode()) {
|
|
case (0x2A): // ROL accumulator
|
|
{
|
|
executeAccumulatorROL(opCode);
|
|
addToProgramAddressAndCycles(1, 2);
|
|
break;
|
|
}
|
|
case (0x2E): // ROL #addr
|
|
{
|
|
executeMemoryROL(opCode);
|
|
if (accumulatorIs8BitWide()) {
|
|
addToProgramAddressAndCycles(3, 6);
|
|
} else {
|
|
addToProgramAddressAndCycles(3, 8);
|
|
}
|
|
break;
|
|
}
|
|
case (0x26): // ROL Direct Page
|
|
{
|
|
executeMemoryROL(opCode);
|
|
int opCycles = Binary::lower8BitsOf(mD) != 0 ? 1 : 0;
|
|
if (accumulatorIs8BitWide()) {
|
|
addToProgramAddressAndCycles(2, 5+opCycles);
|
|
} else {
|
|
addToProgramAddressAndCycles(2, 7+opCycles);
|
|
}
|
|
break;
|
|
}
|
|
case (0x3E): // ROL Absolute Indexed, X
|
|
{
|
|
executeMemoryROL(opCode);
|
|
#ifdef EMU_65C02
|
|
short opCycles = opCodeAddressingCrossesPageBoundary(opCode) ? 0 : -1;
|
|
#else
|
|
short opCycles = 0;
|
|
#endif
|
|
if (accumulatorIs8BitWide()) {
|
|
addToProgramAddressAndCycles(3, 7+opCycles);
|
|
} else {
|
|
addToProgramAddressAndCycles(3, 9+opCycles);
|
|
}
|
|
break;
|
|
}
|
|
case (0x36): // ROL Direct Page Indexed, X
|
|
{
|
|
executeMemoryROL(opCode);
|
|
int opCycles = Binary::lower8BitsOf(mD) != 0 ? 1 : 0;
|
|
if (accumulatorIs8BitWide()) {
|
|
addToProgramAddressAndCycles(2, 6+opCycles);
|
|
} else {
|
|
addToProgramAddressAndCycles(2, 8+opCycles);
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
{
|
|
LOG_UNEXPECTED_OPCODE(opCode);
|
|
}
|
|
}
|
|
}
|