/***************************************************************************** * * arm7exec.c * Portable ARM7TDMI Core Emulator * * Copyright (c) 2004 Steve Ellenoff, all rights reserved. * * - This source code is released as freeware for non-commercial purposes. * - You are free to use and redistribute this code in modified or * unmodified form, provided you list me in the credits. * - If you modify this source code, you must add a notice to each modified * source file that it has been changed. If you're a nice person, you * will clearly mark each change too. :) * - If you wish to use this for commercial purposes, please contact me at * sellenoff@hotmail.com * - The author of this copywritten work reserves the right to change the * terms of its usage and license at any time, including retroactively * - This entire notice must remain in the source code. * * This work is based on: * #1) 'Atmel Corporation ARM7TDMI (Thumb) Datasheet - January 1999' * #2) Arm 2/3/6 emulator By Bryan McPhail (bmcphail@tendril.co.uk) and Phil Stroffolino (MAME CORE 0.76) * *****************************************************************************/ /****************************************************************************** * Notes: * This file contains the code to run during the CPU EXECUTE METHOD. * It has been split into it's own file (from the arm7core.c) so it can be * directly compiled into any cpu core that wishes to use it. * * It should be included as follows in your cpu core: * * int arm7_execute( int cycles ) * { * #include "arm7exec.c" * } * *****************************************************************************/ /* This implementation uses an improved switch() for hopefully faster opcode fetches compared to my last version .. though there's still room for improvement. */ { UINT32 pc; UINT32 insn; ARM7_ICOUNT = cycles; do { CALL_MAME_DEBUG; /* handle Thumb instructions if active */ if( T_IS_SET(GET_CPSR) ) { UINT32 readword; UINT32 addr; UINT32 rm, rn, rs, rd, op2, imm, rrs, rrd; INT32 offs; pc = R15; insn = cpu_readop16(pc & (~1)); ARM7_ICOUNT -= (3 - thumbCycles[insn >> 8]); switch( ( insn & THUMB_INSN_TYPE ) >> THUMB_INSN_TYPE_SHIFT ) { case 0x0: /* Logical shifting */ SET_CPSR(GET_CPSR &~ (N_MASK | Z_MASK)); if( insn & THUMB_SHIFT_R ) /* Shift right */ { rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrs = GET_REGISTER(rs); offs = ( insn & THUMB_SHIFT_AMT ) >> THUMB_SHIFT_AMT_SHIFT; if( offs != 0 ) { SET_REGISTER( rd, rrs >> offs ); if( rrs & ( 1 << (offs-1) ) ) { SET_CPSR(GET_CPSR | C_MASK); } else { SET_CPSR(GET_CPSR &~ C_MASK); } } else { SET_REGISTER( rd, 0 ); if( rrs & 0x80000000 ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } } SET_CPSR(GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; } else /* Shift left */ { rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrs = GET_REGISTER(rs); offs = ( insn & THUMB_SHIFT_AMT ) >> THUMB_SHIFT_AMT_SHIFT; if( offs != 0 ) { SET_REGISTER( rd, rrs << offs ); if( rrs & ( 1 << ( 31 - ( offs - 1 ) ) ) ) { SET_CPSR(GET_CPSR | C_MASK); } else { SET_CPSR(GET_CPSR &~ C_MASK); } } else { SET_REGISTER( rd, rrs ); } SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; } break; case 0x1: /* Arithmetic */ if( insn & THUMB_INSN_ADDSUB ) { switch( ( insn & THUMB_ADDSUB_TYPE ) >> THUMB_ADDSUB_TYPE_SHIFT ) { case 0x0: /* ADD Rd, Rs, Rn */ rn = GET_REGISTER( ( insn & THUMB_ADDSUB_RNIMM ) >> THUMB_ADDSUB_RNIMM_SHIFT ); rs = GET_REGISTER( ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT ); rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, rs + rn ); HandleThumbALUAddFlags( GET_REGISTER(rd), rs, rn ); break; case 0x1: /* SUB Rd, Rs, Rn */ rn = GET_REGISTER( ( insn & THUMB_ADDSUB_RNIMM ) >> THUMB_ADDSUB_RNIMM_SHIFT ); rs = GET_REGISTER( ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT ); rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, rs - rn ); HandleThumbALUSubFlags( GET_REGISTER(rd), rs, rn ); break; case 0x2: /* ADD Rd, Rs, #imm */ imm = ( insn & THUMB_ADDSUB_RNIMM ) >> THUMB_ADDSUB_RNIMM_SHIFT; rs = GET_REGISTER( ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT ); rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, rs + imm ); HandleThumbALUAddFlags( GET_REGISTER(rd), rs, imm ); break; case 0x3: /* SUB Rd, Rs, #imm */ imm = ( insn & THUMB_ADDSUB_RNIMM ) >> THUMB_ADDSUB_RNIMM_SHIFT; rs = GET_REGISTER( ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT ); rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, rs - imm ); HandleThumbALUSubFlags( GET_REGISTER(rd), rs,imm ); break; default: fatalerror("%08x: G1 Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } } else { /* ASR.. */ //if( insn & THUMB_SHIFT_R ) /* Shift right */ { rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrs = GET_REGISTER(rs); offs = ( insn & THUMB_SHIFT_AMT ) >> THUMB_SHIFT_AMT_SHIFT; if( offs == 0 ) { offs = 32; } if( offs >= 32 ) { if( rrs >> 31 ) { SET_CPSR(GET_CPSR | C_MASK); } else { SET_CPSR(GET_CPSR &~ C_MASK); } SET_REGISTER( rd, ( rrs & 0x80000000 ) ? 0xFFFFFFFF : 0x00000000 ); } else { if( ( rrs >> ( offs - 1 ) ) & 1 ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } SET_REGISTER( rd, ( rrs & 0x80000000 ) ? ( ( 0xFFFFFFFF << ( 32 - offs ) ) | ( rrs >> offs ) ) : ( rrs >> offs ) ); } SET_CPSR(GET_CPSR &~ (N_MASK | Z_MASK)); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; } } break; case 0x2: /* CMP / MOV */ if( insn & THUMB_INSN_CMP ) { rn = GET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT ); op2 = ( insn & THUMB_INSN_IMM ); rd = rn - op2; HandleThumbALUSubFlags( rd, rn, op2 ); //mame_printf_debug("%08x: xxx Thumb instruction: CMP R%d (%08x), %02x (N=%d, Z=%d, C=%d, V=%d)\n", pc, ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, GET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT ), op2, N_IS_SET(GET_CPSR) ? 1 : 0, Z_IS_SET(GET_CPSR) ? 1 : 0, C_IS_SET(GET_CPSR) ? 1 : 0, V_IS_SET(GET_CPSR) ? 1 : 0); } else { rd = ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT; op2 = ( insn & THUMB_INSN_IMM ); SET_REGISTER( rd, op2 ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; } break; case 0x3: /* ADD/SUB immediate */ if( insn & THUMB_INSN_SUB ) /* SUB Rd, #Offset8 */ { rn = GET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT ); op2 = ( insn & THUMB_INSN_IMM ); //mame_printf_debug("%08x: Thumb instruction: SUB R%d, %02x\n", pc, ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, op2); rd = rn - op2; SET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, rd ); HandleThumbALUSubFlags( rd, rn, op2 ); } else /* ADD Rd, #Offset8 */ { rn = GET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT ); op2 = insn & THUMB_INSN_IMM; rd = rn + op2; //mame_printf_debug("%08x: Thumb instruction: ADD R%d, %02x\n", pc, ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, op2); SET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, rd ); HandleThumbALUAddFlags( rd, rn, op2 ); } break; case 0x4: /* Rd & Rm instructions */ switch( ( insn & THUMB_GROUP4_TYPE ) >> THUMB_GROUP4_TYPE_SHIFT ) { case 0x0: switch( ( insn & THUMB_ALUOP_TYPE ) >> THUMB_ALUOP_TYPE_SHIFT ) { case 0x0: /* AND Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, GET_REGISTER(rd) & GET_REGISTER(rs) ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0x1: /* EOR Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, GET_REGISTER(rd) ^ GET_REGISTER(rs) ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0x2: /* LSL Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrd = GET_REGISTER(rd); offs = GET_REGISTER(rs) & 0x000000ff; if (offs > 0) { if ( offs < 32 ) { SET_REGISTER( rd, rrd << offs ); if( rrd & ( 1 << ( 31 - ( offs - 1 ) ) ) ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } } else if( offs == 32 ) { SET_REGISTER( rd, 0 ); if( rrd & 1 ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } } else { SET_REGISTER( rd, 0 ); SET_CPSR( GET_CPSR &~ C_MASK ); } } SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0x3: /* LSR Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrd = GET_REGISTER(rd); offs = GET_REGISTER(rs) & 0x000000ff; if (offs > 0) { if( offs < 32 ) { SET_REGISTER( rd, rrd >> offs ); if( rrd & ( 1 << ( offs - 1 ) ) ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } } else if( offs == 32 ) { SET_REGISTER( rd, 0 ); if( rrd & 0x80000000 ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } } else { SET_REGISTER( rd, 0 ); SET_CPSR( GET_CPSR &~ C_MASK ); } } SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0x4: /* ASR Rd, Rs */ { rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrs = GET_REGISTER(rs)&0xff; rrd = GET_REGISTER(rd); if (rrs != 0) { if (rrs >= 32) { if (rrd>>31) { SET_CPSR(GET_CPSR | C_MASK); } else { SET_CPSR(GET_CPSR &~ C_MASK); } SET_REGISTER( rd, (GET_REGISTER(rd) & 0x80000000) ? 0xFFFFFFFF : 0x00000000 ); } else { if ((rrd>>(rs-1))&1) { SET_CPSR(GET_CPSR | C_MASK); } else { SET_CPSR(GET_CPSR &~ C_MASK); } SET_REGISTER( rd, (rrd & 0x80000000) ? ((0xFFFFFFFF<<(32-rrs)) | (rrd>>rrs)) : (rrd>>rrs)); } } SET_CPSR(GET_CPSR &~ (N_MASK | Z_MASK)); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; } break; case 0x5: /* ADC Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; op2=(GET_CPSR & C_MASK) ? 1 : 0; rn=GET_REGISTER(rd) + GET_REGISTER(rs) + op2; HandleThumbALUAddFlags( rn, GET_REGISTER(rd), ( GET_REGISTER(rs) ) ); //? SET_REGISTER( rd, rn); break; case 0x6: /* SBC Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; op2=(GET_CPSR & C_MASK) ? 0 : 1; rn=GET_REGISTER(rd) - GET_REGISTER(rs) - op2; HandleThumbALUSubFlags( rn, GET_REGISTER(rd), ( GET_REGISTER(rs) ) ); //? SET_REGISTER( rd, rn); break; case 0x7: /* ROR Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrd = GET_REGISTER(rd); imm = GET_REGISTER(rs) & 0x0000001f; SET_REGISTER( rd, ( rrd >> imm ) | ( rrd << ( 32 - imm ) ) ); if( rrd & ( 1 << ( imm - 1 ) ) ) { SET_CPSR( GET_CPSR | C_MASK ); } else { SET_CPSR( GET_CPSR &~ C_MASK ); } SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0x8: /* TST Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) & GET_REGISTER(rs) ) ); R15 += 2; break; case 0x9: /* NEG Rd, Rs - todo: check me */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rrs = GET_REGISTER(rs); rn = 0 - rrs; SET_REGISTER( rd, rn ); HandleThumbALUSubFlags( GET_REGISTER(rd), 0, rrs ); break; case 0xa: /* CMP Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rn = GET_REGISTER(rd) - GET_REGISTER(rs); HandleThumbALUSubFlags( rn, GET_REGISTER(rd), GET_REGISTER(rs) ); break; case 0xb: /* CMN Rd, Rs - check flags, add dasm */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rn = GET_REGISTER(rd) + GET_REGISTER(rs); HandleThumbALUAddFlags( rn, GET_REGISTER(rd), GET_REGISTER(rs) ); break; case 0xc: /* ORR Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, GET_REGISTER(rd) | GET_REGISTER(rs) ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0xd: /* MUL Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; rn = GET_REGISTER(rd) * GET_REGISTER(rs); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_REGISTER( rd, rn ); SET_CPSR( GET_CPSR | HandleALUNZFlags( rn ) ); R15 += 2; break; case 0xe: /* BIC Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, GET_REGISTER(rd) & (~GET_REGISTER(rs)) ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; case 0xf: /* MVN Rd, Rs */ rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; op2 = GET_REGISTER(rs); SET_REGISTER( rd, ~op2 ); SET_CPSR( GET_CPSR &~ ( Z_MASK | N_MASK ) ); SET_CPSR( GET_CPSR | HandleALUNZFlags( GET_REGISTER(rd) ) ); R15 += 2; break; default: fatalerror("%08x: G4-0 Undefined Thumb instruction: %04x %x\n", pc, insn, ( insn & THUMB_ALUOP_TYPE ) >> THUMB_ALUOP_TYPE_SHIFT); R15 += 2; break; } break; case 0x1: switch( ( insn & THUMB_HIREG_OP ) >> THUMB_HIREG_OP_SHIFT ) { case 0x0: /* ADD Rd, Rs */ rs = ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT; rd = insn & THUMB_HIREG_RD; switch( ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT ) { case 0x1: /* ADD Rd, HRs */ SET_REGISTER( rd, GET_REGISTER(rd) + GET_REGISTER(rs+8) ); // emulate the effects of pre-fetch if (rs == 7) { SET_REGISTER(rd, GET_REGISTER(rd) + 4); } break; case 0x2: /* ADD HRd, Rs */ SET_REGISTER( rd+8, GET_REGISTER(rd+8) + GET_REGISTER(rs) ); if (rd == 7) { R15 += 2; change_pc(R15); } break; case 0x3: /* Add HRd, HRs */ SET_REGISTER( rd+8, GET_REGISTER(rd+8) + GET_REGISTER(rs+8) ); // emulate the effects of pre-fetch if (rs == 7) { SET_REGISTER(rd+8, GET_REGISTER(rd+8) + 4); } if (rd == 7) { R15 += 2; change_pc(R15); } break; default: fatalerror("%08x: G4-1-0 Undefined Thumb instruction: %04x %x\n", pc, insn, ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT ); break; } R15 += 2; break; case 0x1: /* CMP */ switch( ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT ) { case 0x0: /* CMP Rd, Rs */ rs = GET_REGISTER( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) ); rd = GET_REGISTER( insn & THUMB_HIREG_RD ); rn = rd - rs; HandleThumbALUSubFlags( rn, rd, rs ); break; case 0x1: /* CMP Rd, Hs */ rs = GET_REGISTER( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) + 8 ); rd = GET_REGISTER( insn & THUMB_HIREG_RD ); rn = rd - rs; HandleThumbALUSubFlags( rn, rd, rs ); break; case 0x2: /* CMP Hd, Rs */ rs = GET_REGISTER( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) ); rd = GET_REGISTER( (insn & THUMB_HIREG_RD) + 8 ); rn = rd - rs; HandleThumbALUSubFlags( rn, rd, rs ); break; case 0x3: /* CMP Hd, Hs */ rs = GET_REGISTER( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) + 8 ); rd = GET_REGISTER( (insn & THUMB_HIREG_RD) + 8 ); rn = rd - rs; HandleThumbALUSubFlags( rn, rd, rs ); break; default: fatalerror("%08x: G4-1 Undefined Thumb instruction: %04x %x\n", pc, insn, ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT); R15 += 2; break; } break; case 0x2: /* MOV */ switch( ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT ) { case 0x1: // MOV Rd, Hs rs = ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT; rd = insn & THUMB_HIREG_RD; if( rs == 7 ) { SET_REGISTER( rd, GET_REGISTER(rs + 8) + 4 ); } else { SET_REGISTER( rd, GET_REGISTER(rs + 8) ); } R15 += 2; break; case 0x2: // MOV Hd, Rs rs = ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT; rd = insn & THUMB_HIREG_RD; SET_REGISTER( rd + 8, GET_REGISTER(rs) ); if( rd != 7 ) { R15 += 2; } else { R15 &= ~1; change_pc(R15); } break; case 0x3: // MOV Hd, Hs rs = ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT; rd = insn & THUMB_HIREG_RD; if (rs == 7) { SET_REGISTER( rd + 8, GET_REGISTER(rs+8)+4 ); } else { SET_REGISTER( rd + 8, GET_REGISTER(rs+8) ); } if( rd != 7 ) { R15 += 2; } if( rd == 7 ) { R15 &= ~1; change_pc(R15); } break; default: fatalerror("%08x: G4-2 Undefined Thumb instruction: %04x (%x)\n", pc, insn, ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT); R15 += 2; break; } break; case 0x3: switch( ( insn & THUMB_HIREG_H ) >> THUMB_HIREG_H_SHIFT ) { case 0x0: rd = ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT; addr = GET_REGISTER(rd); if( addr & 1 ) { addr &= ~1; } else { SET_CPSR(GET_CPSR &~ T_MASK); if( addr & 2 ) { addr += 2; } } R15 = addr; break; case 0x1: addr = GET_REGISTER( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) + 8 ); if( ( ( ( insn & THUMB_HIREG_RS ) >> THUMB_HIREG_RS_SHIFT ) + 8 ) == 15 ) { addr += 2; } if( addr & 1 ) { addr &= ~1; } else { SET_CPSR(GET_CPSR &~ T_MASK); if( addr & 2 ) { addr += 2; } } R15 = addr; break; default: fatalerror("%08x: G4-3 Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } break; default: fatalerror("%08x: G4-x Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } break; case 0x2: case 0x3: readword = READ32( ( R15 & ~2 ) + 4 + ( ( insn & THUMB_INSN_IMM ) << 2 ) ); SET_REGISTER( ( insn & THUMB_INSN_IMM_RD ) >> THUMB_INSN_IMM_RD_SHIFT, readword ); R15 += 2; break; default: fatalerror("%08x: G4-y Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } break; case 0x5: /* LDR* STR* */ switch( ( insn & THUMB_GROUP5_TYPE ) >> THUMB_GROUP5_TYPE_SHIFT ) { case 0x0: /* STR Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); WRITE32( addr, GET_REGISTER(rd) ); R15 += 2; break; case 0x1: /* STRH Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); WRITE16( addr, GET_REGISTER(rd) ); R15 += 2; break; case 0x2: /* STRB Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); WRITE8( addr, GET_REGISTER(rd) ); R15 += 2; break; case 0x3: /* LDSB Rd, [Rn, Rm] todo, add dasm */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); op2 = READ8( addr ); if( op2 & 0x00000080 ) { op2 |= 0xffffff00; } SET_REGISTER( rd, op2 ); R15 += 2; break; case 0x4: /* LDR Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); op2 = READ32( addr ); SET_REGISTER( rd, op2 ); R15 += 2; break; case 0x5: /* LDRH Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); op2 = READ16( addr ); SET_REGISTER( rd, op2 ); R15 += 2; break; case 0x6: /* LDRB Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); op2 = READ8( addr ); SET_REGISTER( rd, op2 ); R15 += 2; break; case 0x7: /* LDSH Rd, [Rn, Rm] */ rm = ( insn & THUMB_GROUP5_RM ) >> THUMB_GROUP5_RM_SHIFT; rn = ( insn & THUMB_GROUP5_RN ) >> THUMB_GROUP5_RN_SHIFT; rd = ( insn & THUMB_GROUP5_RD ) >> THUMB_GROUP5_RD_SHIFT; addr = GET_REGISTER(rn) + GET_REGISTER(rm); op2 = READ16( addr ); if( op2 & 0x00008000 ) { op2 |= 0xffff0000; } SET_REGISTER( rd, op2 ); R15 += 2; break; default: fatalerror("%08x: G5 Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } break; case 0x6: /* Word Store w/ Immediate Offset */ if( insn & THUMB_LSOP_L ) /* Load */ { rn = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = insn & THUMB_ADDSUB_RD; offs = ( ( insn & THUMB_LSOP_OFFS ) >> THUMB_LSOP_OFFS_SHIFT ) << 2; SET_REGISTER( rd, READ32(GET_REGISTER(rn) + offs) ); // fix R15 += 2; } else /* Store */ { rn = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = insn & THUMB_ADDSUB_RD; offs = ( ( insn & THUMB_LSOP_OFFS ) >> THUMB_LSOP_OFFS_SHIFT ) << 2; WRITE32( GET_REGISTER(rn) + offs, GET_REGISTER(rd) ); R15 += 2; } break; case 0x7: /* Byte Store w/ Immeidate Offset */ if( insn & THUMB_LSOP_L ) /* Load */ { rn = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = insn & THUMB_ADDSUB_RD; offs = ( insn & THUMB_LSOP_OFFS ) >> THUMB_LSOP_OFFS_SHIFT; SET_REGISTER( rd, READ8( GET_REGISTER(rn) + offs ) ); R15 += 2; } else /* Store */ { rn = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = insn & THUMB_ADDSUB_RD; offs = ( insn & THUMB_LSOP_OFFS ) >> THUMB_LSOP_OFFS_SHIFT; WRITE8( GET_REGISTER(rn) + offs, GET_REGISTER(rd) ); R15 += 2; } break; case 0x8: /* Load/Store Halfword */ if( insn & THUMB_HALFOP_L ) /* Load */ { imm = ( insn & THUMB_HALFOP_OFFS ) >> THUMB_HALFOP_OFFS_SHIFT; rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; SET_REGISTER( rd, READ16( GET_REGISTER(rs) + ( imm << 1 ) ) ); R15 += 2; } else /* Store */ { imm = ( insn & THUMB_HALFOP_OFFS ) >> THUMB_HALFOP_OFFS_SHIFT; rs = ( insn & THUMB_ADDSUB_RS ) >> THUMB_ADDSUB_RS_SHIFT; rd = ( insn & THUMB_ADDSUB_RD ) >> THUMB_ADDSUB_RD_SHIFT; WRITE16( GET_REGISTER(rs) + ( imm << 1 ), GET_REGISTER(rd) ); R15 += 2; } break; case 0x9: /* Stack-Relative Load/Store */ if( insn & THUMB_STACKOP_L ) { rd = ( insn & THUMB_STACKOP_RD ) >> THUMB_STACKOP_RD_SHIFT; offs = (UINT8)( insn & THUMB_INSN_IMM ); readword = READ32( GET_REGISTER(13) + ( (UINT32)offs << 2 ) ); SET_REGISTER( rd, readword ); R15 += 2; } else { rd = ( insn & THUMB_STACKOP_RD ) >> THUMB_STACKOP_RD_SHIFT; offs = (UINT8)( insn & THUMB_INSN_IMM ); WRITE32( GET_REGISTER(13) + ( (UINT32)offs << 2 ), GET_REGISTER(rd) ); R15 += 2; } break; case 0xa: /* Get relative address */ if( insn & THUMB_RELADDR_SP ) /* ADD Rd, SP, #nn */ { rd = ( insn & THUMB_RELADDR_RD ) >> THUMB_RELADDR_RD_SHIFT; offs = (UINT8)( insn & THUMB_INSN_IMM ) << 2; SET_REGISTER( rd, GET_REGISTER(13) + offs ); R15 += 2; } else /* ADD Rd, PC, #nn */ { rd = ( insn & THUMB_RELADDR_RD ) >> THUMB_RELADDR_RD_SHIFT; offs = (UINT8)( insn & THUMB_INSN_IMM ) << 2; SET_REGISTER( rd, ( ( R15 + 4 ) & ~2 ) + offs ); R15 += 2; } break; case 0xb: /* Stack-Related Opcodes */ switch( ( insn & THUMB_STACKOP_TYPE ) >> THUMB_STACKOP_TYPE_SHIFT ) { case 0x0: /* ADD SP, #imm */ addr = ( insn & THUMB_INSN_IMM ); addr &= ~THUMB_INSN_IMM_S; SET_REGISTER( 13, GET_REGISTER(13) + ( ( insn & THUMB_INSN_IMM_S ) ? -( addr << 2 ) : ( addr << 2 ) ) ); R15 += 2; break; case 0x4: /* PUSH {Rlist} */ for( offs = 7; offs >= 0; offs-- ) { if( insn & ( 1 << offs ) ) { SET_REGISTER( 13, GET_REGISTER(13) - 4 ); WRITE32( GET_REGISTER(13), GET_REGISTER(offs) ); } } R15 += 2; break; case 0x5: /* PUSH {Rlist}{LR} */ SET_REGISTER( 13, GET_REGISTER(13) - 4 ); WRITE32( GET_REGISTER(13), GET_REGISTER(14) ); for( offs = 7; offs >= 0; offs-- ) { if( insn & ( 1 << offs ) ) { SET_REGISTER( 13, GET_REGISTER(13) - 4 ); WRITE32( GET_REGISTER(13), GET_REGISTER(offs) ); } } R15 += 2; break; case 0xc: /* POP {Rlist} */ for( offs = 0; offs < 8; offs++ ) { if( insn & ( 1 << offs ) ) { SET_REGISTER( offs, READ32( GET_REGISTER(13) ) ); SET_REGISTER( 13, GET_REGISTER(13) + 4 ); } } R15 += 2; break; case 0xd: /* POP {Rlist}{PC} */ for( offs = 0; offs < 8; offs++ ) { if( insn & ( 1 << offs ) ) { SET_REGISTER( offs, READ32( GET_REGISTER(13) ) ); SET_REGISTER( 13, GET_REGISTER(13) + 4 ); } } R15 = READ32( GET_REGISTER(13) ) & ~1; SET_REGISTER( 13, GET_REGISTER(13) + 4 ); break; default: fatalerror("%08x: Gb Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } break; case 0xc: /* Multiple Load/Store */ if( insn & THUMB_MULTLS ) /* Load */ { rd = ( insn & THUMB_MULTLS_BASE ) >> THUMB_MULTLS_BASE_SHIFT; for( offs = 0; offs < 8; offs++ ) { if( insn & ( 1 << offs ) ) { SET_REGISTER( offs, READ32( (GET_REGISTER(rd)&0xfffffffc) ) ); SET_REGISTER( rd, GET_REGISTER(rd) + 4 ); } } R15 += 2; } else /* Store */ { rd = ( insn & THUMB_MULTLS_BASE ) >> THUMB_MULTLS_BASE_SHIFT; for( offs = 0; offs < 8; offs++ ) { if( insn & ( 1 << offs ) ) { WRITE32( (GET_REGISTER(rd)&0xfffffffc), GET_REGISTER(offs) ); SET_REGISTER( rd, GET_REGISTER(rd) + 4 ); } } R15 += 2; } break; case 0xd: /* Conditional Branch */ offs = (INT8)( insn & THUMB_INSN_IMM ); switch( ( insn & THUMB_COND_TYPE ) >> THUMB_COND_TYPE_SHIFT ) { case COND_EQ: if( Z_IS_SET(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_NE: if( Z_IS_CLEAR(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_CS: if( C_IS_SET(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_CC: if( C_IS_CLEAR(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_MI: if( N_IS_SET(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_PL: if( N_IS_CLEAR(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_VS: if( V_IS_SET(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_VC: if( V_IS_CLEAR(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_HI: if( C_IS_SET(GET_CPSR) && Z_IS_CLEAR(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_LS: if( C_IS_CLEAR(GET_CPSR) || Z_IS_SET(GET_CPSR) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_GE: if( !(GET_CPSR & N_MASK) == !(GET_CPSR & V_MASK) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_LT: if( !(GET_CPSR & N_MASK) != !(GET_CPSR & V_MASK) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_GT: if( Z_IS_CLEAR(GET_CPSR) && ( !(GET_CPSR & N_MASK) == !(GET_CPSR & V_MASK) ) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_LE: if( Z_IS_SET(GET_CPSR) || ( !(GET_CPSR & N_MASK) != !(GET_CPSR & V_MASK) ) ) { R15 += 4 + (offs << 1); } else { R15 += 2; } break; case COND_AL: fatalerror("%08x: Undefined Thumb instruction: %04x (ARM9 reserved)\n", pc, insn); R15 += 2; break; case COND_NV: // SWI (this is sort of a "hole" in the opcode encoding) ARM7.pendingSwi = 1; ARM7_CHECKIRQ; break; } break; case 0xe: /* B #offs */ offs = ( insn & THUMB_BRANCH_OFFS ) << 1; if( offs & 0x00000800 ) { offs |= 0xfffff800; } R15 += 4 + offs; break; case 0xf: /* BL */ if( insn & THUMB_BLOP_LO ) { addr = GET_REGISTER(14); addr += ( insn & THUMB_BLOP_OFFS ) << 1; SET_REGISTER( 14, ( R15 + 2 ) | 1 ); R15 = addr; // R15 += 2; } else { addr = ( insn & THUMB_BLOP_OFFS ) << 12; if( addr & ( 1 << 22 ) ) { addr |= 0xff800000; } addr += R15 + 4; SET_REGISTER( 14, addr ); R15 += 2; } break; default: fatalerror("%08x: Undefined Thumb instruction: %04x\n", pc, insn); R15 += 2; break; } } else { /* load 32 bit instruction */ pc = R15; insn = cpu_readop32(pc); /* process condition codes for this instruction */ switch (insn >> INSN_COND_SHIFT) { case COND_EQ: if (Z_IS_CLEAR(GET_CPSR)) goto L_Next; break; case COND_NE: if (Z_IS_SET(GET_CPSR)) goto L_Next; break; case COND_CS: if (C_IS_CLEAR(GET_CPSR)) goto L_Next; break; case COND_CC: if (C_IS_SET(GET_CPSR)) goto L_Next; break; case COND_MI: if (N_IS_CLEAR(GET_CPSR)) goto L_Next; break; case COND_PL: if (N_IS_SET(GET_CPSR)) goto L_Next; break; case COND_VS: if (V_IS_CLEAR(GET_CPSR)) goto L_Next; break; case COND_VC: if (V_IS_SET(GET_CPSR)) goto L_Next; break; case COND_HI: if (C_IS_CLEAR(GET_CPSR) || Z_IS_SET(GET_CPSR)) goto L_Next; break; case COND_LS: if (C_IS_SET(GET_CPSR) && Z_IS_CLEAR(GET_CPSR)) goto L_Next; break; case COND_GE: if (!(GET_CPSR & N_MASK) != !(GET_CPSR & V_MASK)) goto L_Next; /* Use x ^ (x >> ...) method */ break; case COND_LT: if (!(GET_CPSR & N_MASK) == !(GET_CPSR & V_MASK)) goto L_Next; break; case COND_GT: if (Z_IS_SET(GET_CPSR) || (!(GET_CPSR & N_MASK) != !(GET_CPSR & V_MASK))) goto L_Next; break; case COND_LE: if (Z_IS_CLEAR(GET_CPSR) && (!(GET_CPSR & N_MASK) == !(GET_CPSR & V_MASK))) goto L_Next; break; case COND_NV: goto L_Next; } /*******************************************************************/ /* If we got here - condition satisfied, so decode the instruction */ /*******************************************************************/ switch( (insn & 0xF000000)>>24 ) { case 0: case 1: case 2: case 3: /* Branch and Exchange (BX) */ if( (insn&0x0ffffff0)==0x012fff10 ) //bits 27-4 == 000100101111111111110001 { R15 = GET_REGISTER(insn & 0x0f); //If new PC address has A0 set, switch to Thumb mode if(R15 & 1) { SET_CPSR(GET_CPSR|T_MASK); R15--; } } else /* Multiply OR Swap OR Half Word Data Transfer */ if( (insn & 0x0e000000)==0 && (insn & 0x80) && (insn & 0x10) ) //bits 27-25 == 000, bit 7=1, bit 4=1 { /* Half Word Data Transfer */ if(insn & 0x60) //bits = 6-5 != 00 { HandleHalfWordDT(insn); } else /* Swap */ if(insn & 0x01000000) //bit 24 = 1 { HandleSwap(insn); } /* Multiply Or Multiply Long */ else { /* multiply long */ if( insn&0x800000 ) //Bit 23 = 1 for Multiply Long { /* Signed? */ if( insn&0x00400000 ) HandleSMulLong(insn); else HandleUMulLong(insn); } /* multiply */ else { HandleMul(insn); } R15 += 4; } } else /* Data Processing OR PSR Transfer */ if( (insn & 0x0c000000) ==0 ) //bits 27-26 == 00 - This check can only exist properly after Multiplication check above { /* PSR Transfer (MRS & MSR) */ if( ((insn&0x0100000)==0) && ((insn&0x01800000)==0x01000000) ) //( S bit must be clear, and bit 24,23 = 10 ) { HandlePSRTransfer(insn); ARM7_ICOUNT += 2; //PSR only takes 1 - S Cycle, so we add + 2, since at end, we -3.. R15 += 4; } /* Data Processing */ else { HandleALU(insn); } } break; /* Data Transfer - Single Data Access */ case 4: case 5: case 6: case 7: HandleMemSingle(insn); R15 += 4; break; /* Block Data Transfer/Access */ case 8: case 9: HandleMemBlock(insn); R15 += 4; break; /* Branch or Branch & Link */ case 0xa: case 0xb: HandleBranch(insn); break; /* Co-Processor Data Transfer */ case 0xc: case 0xd: HandleCoProcDT(insn); R15 += 4; break; /* Co-Processor Data Operation or Register Transfer */ case 0xe: if(insn & 0x10) HandleCoProcRT(insn); else HandleCoProcDO(insn); R15 += 4; break; /* Software Interrupt */ case 0x0f: ARM7.pendingSwi = 1; ARM7_CHECKIRQ; //couldn't find any cycle counts for SWI break; /* Undefined */ default: ARM7.pendingSwi = 1; ARM7_CHECKIRQ; ARM7_ICOUNT -= 1; //undefined takes 4 cycles (page 77) LOG(("%08x: Undefined instruction\n",pc-4)); L_Next: R15 += 4; ARM7_ICOUNT +=2; //Any unexecuted instruction only takes 1 cycle (page 193) } } change_pc(R15); ARM7_CHECKIRQ; /* All instructions remove 3 cycles.. Others taking less / more will have adjusted this # prior to here */ ARM7_ICOUNT -= 3; } while( ARM7_ICOUNT > 0 ); return cycles - ARM7_ICOUNT; }