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[/] [s80186/] [trunk/] [sim/] [cppmodel/] [instructions/] [inc_dec.cpp] - Rev 2
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// Copyright Jamie Iles, 2017 // // This file is part of s80x86. // // s80x86 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, either version 3 of the License, or // (at your option) any later version. // // s80x86 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 s80x86. If not, see <http://www.gnu.org/licenses/>. // inc r/m, 8-bit void EmulatorPimpl::inc_dec_fe() { modrm_decoder->set_width(OP_WIDTH_8); modrm_decoder->decode(); if (modrm_decoder->raw_reg() == 7) { invalid_opcode(); return; } if (modrm_decoder->raw_reg() != 0 && modrm_decoder->raw_reg() != 1) { std::cerr << "warning: invalid reg " << std::hex << (unsigned)modrm_decoder->raw_reg() << " for opcode 0x" << opcode << std::endl; return; } uint8_t v = read_data<uint8_t>(); uint8_t result; uint16_t flags; if (modrm_decoder->raw_reg() == 0) std::tie(flags, result) = do_add<uint8_t>(v, 1); else std::tie(flags, result) = do_sub<uint8_t>(v, 1); registers->set_flags(flags, OF | SF | ZF | AF | PF); write_data<uint8_t>(result); } // inc r/m, 16-bit void EmulatorPimpl::incff() { assert(modrm_decoder->raw_reg() == 0); uint16_t v = read_data<uint16_t>(); uint16_t result; uint16_t flags; std::tie(flags, result) = do_add<uint16_t>(v, 1); registers->set_flags(flags, OF | SF | ZF | AF | PF); write_data<uint16_t>(result); } // inc r, 16-bit void EmulatorPimpl::inc40_47() { auto reg = static_cast<GPR>(static_cast<int>(AX) + (opcode & 0x7)); auto v = registers->get(reg); uint16_t result; uint16_t flags; std::tie(flags, result) = do_add<uint16_t>(v, 1); registers->set_flags(flags, OF | SF | ZF | AF | PF); registers->set(reg, result); } // dec r/m, 16-bit void EmulatorPimpl::decff() { assert(modrm_decoder->raw_reg() == 1); uint16_t v = read_data<uint16_t>(); uint16_t result; uint16_t flags; std::tie(flags, result) = do_sub<uint16_t>(v, 1); registers->set_flags(flags, OF | SF | ZF | AF | PF); write_data<uint16_t>(result); } // dec r, 16-bit void EmulatorPimpl::dec48_4f() { auto reg = static_cast<GPR>(static_cast<int>(AX) + (opcode & 0x7)); auto v = registers->get(reg); uint16_t result; uint16_t flags; std::tie(flags, result) = do_sub<uint16_t>(v, 1); registers->set_flags(flags, OF | SF | ZF | AF | PF); registers->set(reg, result); }