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[/] [ao486/] [trunk/] [bochs486/] [cpu/] [shift8.cc] - Rev 2
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///////////////////////////////////////////////////////////////////////// // $Id: shift8.cc 11313 2012-08-05 13:52:40Z sshwarts $ ///////////////////////////////////////////////////////////////////////// // // Copyright (C) 2001-2012 The Bochs Project // // This library is free software; you can redistribute it and/or // modify it under the terms of the GNU Lesser General Public // License as published by the Free Software Foundation; either // version 2 of the License, or (at your option) any later version. // // This library 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 // Lesser General Public License for more details. // // You should have received a copy of the GNU Lesser General Public // License along with this library; if not, write to the Free Software // Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA B 02110-1301 USA ///////////////////////////////////////////////////////////////////////// #define NEED_CPU_REG_SHORTCUTS 1 #include "bochs.h" #include "cpu.h" #define LOG_THIS BX_CPU_THIS_PTR BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ROL_EbR(bxInstruction_c *i) { unsigned count; unsigned bit0, bit7; if (i->getIaOpcode() == BX_IA_ROL_Eb) count = CL; else count = i->Ib(); Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); if ((count & 0x07) == 0) { if (count & 0x18) { bit0 = (op1_8 & 1); bit7 = (op1_8 >> 7); SET_FLAGS_OxxxxC(bit0 ^ bit7, bit0); } } else { count &= 0x7; // use only lowest 3 bits Bit8u result_8 = (op1_8 << count) | (op1_8 >> (8 - count)); BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); /* set eflags: * ROL count affects the following flags: C, O */ bit0 = (result_8 & 1); bit7 = (result_8 >> 7); SET_FLAGS_OxxxxC(bit0 ^ bit7, bit0); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ROL_EbM(bxInstruction_c *i) { unsigned count; unsigned bit0, bit7; if (i->getIaOpcode() == BX_IA_ROL_Eb) count = CL; else count = i->Ib(); bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); if ((count & 0x07) == 0) { if (count & 0x18) { bit0 = (op1_8 & 1); bit7 = (op1_8 >> 7); SET_FLAGS_OxxxxC(bit0 ^ bit7, bit0); } } else { count &= 0x7; // use only lowest 3 bits Bit8u result_8 = (op1_8 << count) | (op1_8 >> (8 - count)); write_RMW_virtual_byte(result_8); /* set eflags: * ROL count affects the following flags: C, O */ bit0 = (result_8 & 1); bit7 = (result_8 >> 7); SET_FLAGS_OxxxxC(bit0 ^ bit7, bit0); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ROR_EbR(bxInstruction_c *i) { unsigned count; unsigned bit6, bit7; if (i->getIaOpcode() == BX_IA_ROR_Eb) count = CL; else count = i->Ib(); Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); if ((count & 0x07) == 0) { if (count & 0x18) { bit6 = (op1_8 >> 6) & 1; bit7 = (op1_8 >> 7) & 1; SET_FLAGS_OxxxxC(bit6 ^ bit7, bit7); } } else { count &= 0x7; /* use only bottom 3 bits */ Bit8u result_8 = (op1_8 >> count) | (op1_8 << (8 - count)); BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); /* set eflags: * ROR count affects the following flags: C, O */ bit6 = (result_8 >> 6) & 1; bit7 = (result_8 >> 7) & 1; SET_FLAGS_OxxxxC(bit6 ^ bit7, bit7); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::ROR_EbM(bxInstruction_c *i) { unsigned count; unsigned bit6, bit7; if (i->getIaOpcode() == BX_IA_ROR_Eb) count = CL; else count = i->Ib(); bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); if ((count & 0x07) == 0) { if (count & 0x18) { bit6 = (op1_8 >> 6) & 1; bit7 = (op1_8 >> 7) & 1; SET_FLAGS_OxxxxC(bit6 ^ bit7, bit7); } } else { count &= 0x7; /* use only bottom 3 bits */ Bit8u result_8 = (op1_8 >> count) | (op1_8 << (8 - count)); write_RMW_virtual_byte(result_8); /* set eflags: * ROR count affects the following flags: C, O */ bit6 = (result_8 >> 6) & 1; bit7 = (result_8 >> 7) & 1; SET_FLAGS_OxxxxC(bit6 ^ bit7, bit7); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RCL_EbR(bxInstruction_c *i) { Bit8u result_8; unsigned count; unsigned of, cf; if (i->getIaOpcode() == BX_IA_RCL_Eb) count = CL; else count = i->Ib(); count = (count & 0x1f) % 9; if (! count) { BX_NEXT_INSTR(i); } Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); if (count==1) { result_8 = (op1_8 << 1) | getB_CF(); } else { result_8 = (op1_8 << count) | (getB_CF() << (count - 1)) | (op1_8 >> (9 - count)); } BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); cf = (op1_8 >> (8 - count)) & 0x01; of = cf ^ (result_8 >> 7); // of = cf ^ result7 SET_FLAGS_OxxxxC(of, cf); BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RCL_EbM(bxInstruction_c *i) { Bit8u result_8; unsigned count; unsigned of, cf; if (i->getIaOpcode() == BX_IA_RCL_Eb) count = CL; else count = i->Ib(); bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); count = (count & 0x1f) % 9; if (! count) { BX_NEXT_INSTR(i); } if (count==1) { result_8 = (op1_8 << 1) | getB_CF(); } else { result_8 = (op1_8 << count) | (getB_CF() << (count - 1)) | (op1_8 >> (9 - count)); } write_RMW_virtual_byte(result_8); cf = (op1_8 >> (8 - count)) & 0x01; of = cf ^ (result_8 >> 7); // of = cf ^ result7 SET_FLAGS_OxxxxC(of, cf); BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RCR_EbR(bxInstruction_c *i) { unsigned count; unsigned cf, of; if (i->getIaOpcode() == BX_IA_RCR_Eb) count = CL; else count = i->Ib(); count = (count & 0x1f) % 9; if (count) { Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); Bit8u result_8 = (op1_8 >> count) | (getB_CF() << (8 - count)) | (op1_8 << (9 - count)); BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); cf = (op1_8 >> (count - 1)) & 0x1; of = (((result_8 << 1) ^ result_8) >> 7) & 0x1; // of = result6 ^ result7 SET_FLAGS_OxxxxC(of, cf); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::RCR_EbM(bxInstruction_c *i) { unsigned count; unsigned cf, of; if (i->getIaOpcode() == BX_IA_RCR_Eb) count = CL; else count = i->Ib(); bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); count = (count & 0x1f) % 9; if (count) { Bit8u result_8 = (op1_8 >> count) | (getB_CF() << (8 - count)) | (op1_8 << (9 - count)); write_RMW_virtual_byte(result_8); cf = (op1_8 >> (count - 1)) & 0x1; of = (((result_8 << 1) ^ result_8) >> 7) & 0x1; // of = result6 ^ result7 SET_FLAGS_OxxxxC(of, cf); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SHL_EbR(bxInstruction_c *i) { Bit8u result_8; unsigned count; unsigned of = 0, cf = 0; if (i->getIaOpcode() == BX_IA_SHL_Eb) count = CL; else count = i->Ib(); count &= 0x1f; if (!count) { BX_NEXT_INSTR(i); } Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); if (count <= 8) { result_8 = (op1_8 << count); cf = (op1_8 >> (8 - count)) & 0x1; of = cf ^ (result_8 >> 7); } else { result_8 = 0; } BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); SET_FLAGS_OSZAPC_LOGIC_8(result_8); SET_FLAGS_OxxxxC(of, cf); BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SHL_EbM(bxInstruction_c *i) { Bit8u result_8; unsigned count; unsigned of = 0, cf = 0; if (i->getIaOpcode() == BX_IA_SHL_Eb) count = CL; else count = i->Ib(); count &= 0x1f; bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); if (!count) { BX_NEXT_INSTR(i); } if (count <= 8) { result_8 = (op1_8 << count); cf = (op1_8 >> (8 - count)) & 0x1; of = cf ^ (result_8 >> 7); } else { result_8 = 0; } write_RMW_virtual_byte(result_8); SET_FLAGS_OSZAPC_LOGIC_8(result_8); SET_FLAGS_OxxxxC(of, cf); BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SHR_EbR(bxInstruction_c *i) { unsigned count; if (i->getIaOpcode() == BX_IA_SHR_Eb) count = CL; else count = i->Ib(); count &= 0x1f; if (count) { Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); Bit8u result_8 = (op1_8 >> count); BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); unsigned cf = (op1_8 >> (count - 1)) & 0x1; // note, that of == result7 if count == 1 and // of == 0 if count >= 2 unsigned of = (((result_8 << 1) ^ result_8) >> 7) & 0x1; SET_FLAGS_OSZAPC_LOGIC_8(result_8); SET_FLAGS_OxxxxC(of, cf); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SHR_EbM(bxInstruction_c *i) { unsigned count; if (i->getIaOpcode() == BX_IA_SHR_Eb) count = CL; else count = i->Ib(); count &= 0x1f; bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); if (count) { Bit8u result_8 = (op1_8 >> count); write_RMW_virtual_byte(result_8); unsigned cf = (op1_8 >> (count - 1)) & 0x1; // note, that of == result7 if count == 1 and // of == 0 if count >= 2 unsigned of = (((result_8 << 1) ^ result_8) >> 7) & 0x1; SET_FLAGS_OSZAPC_LOGIC_8(result_8); SET_FLAGS_OxxxxC(of, cf); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SAR_EbR(bxInstruction_c *i) { unsigned count; if (i->getIaOpcode() == BX_IA_SAR_Eb) count = CL; else count = i->Ib(); count &= 0x1f; if (count) { Bit8u op1_8 = BX_READ_8BIT_REGx(i->dst(), i->extend8bitL()); Bit8u result_8 = ((Bit8s) op1_8) >> count; BX_WRITE_8BIT_REGx(i->dst(), i->extend8bitL(), result_8); unsigned cf = (((Bit8s) op1_8) >> (count - 1)) & 0x1; SET_FLAGS_OSZAPC_LOGIC_8(result_8); /* signed overflow cannot happen in SAR instruction */ SET_FLAGS_OxxxxC(0, cf); } BX_NEXT_INSTR(i); } BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::SAR_EbM(bxInstruction_c *i) { unsigned count; if (i->getIaOpcode() == BX_IA_SAR_Eb) count = CL; else count = i->Ib(); count &= 0x1f; bx_address eaddr = BX_CPU_CALL_METHODR(i->ResolveModrm, (i)); /* pointer, segment address pair */ Bit8u op1_8 = read_RMW_virtual_byte(i->seg(), eaddr); if (count) { Bit8u result_8 = ((Bit8s) op1_8) >> count; write_RMW_virtual_byte(result_8); unsigned cf = (((Bit8s) op1_8) >> (count - 1)) & 0x1; SET_FLAGS_OSZAPC_LOGIC_8(result_8); /* signed overflow cannot happen in SAR instruction */ SET_FLAGS_OxxxxC(0, cf); } BX_NEXT_INSTR(i); }