rockbox/lib/rbcodec/codecs/libgme/gb_cpu_run.h

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// Game_Music_Emu 0.6-pre. http://www.slack.net/~ant/
#if 0
/* Define these macros in the source file before #including this file.
- Parameters might be expressions, so they are best evaluated only once,
though they NEVER have side-effects, so multiple evaluation is OK.
- Output parameters might be a multiple-assignment expression like "a=x",
so they must NOT be parenthesized.
- Macros "returning" void may use a {} statement block. */
// 0 <= addr <= 0xFFFF + page_size
// time functions can be used
int READ_MEM( addr_t );
void WRITE_MEM( addr_t, int data );
// Access of 0xFF00 + offset
// 0 <= offset <= 0xFF
int READ_IO( int offset );
void WRITE_IO( int offset, int data );
// Often-used instructions use this instead of READ_MEM
void READ_FAST( addr_t, int& out );
// The following can be used within macros:
// Current time
cpu_time_t TIME();
#endif
/* Copyright (C) 2003-2009 Shay Green. This module 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 2.1 of the License, or (at your option) any later version. This
module 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 module; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */
// Common instructions:
//
// 365880 FA LD A,(nn)
// 355863 20 JR NZ
// 313655 21 LD HL,nn
// 274580 28 JR Z
// 252878 FE CP n
// 230541 7E LD A,(HL)
// 226209 2A LD A,(HL+)
// 217467 CD CALL
// 212034 C9 RET
// 208376 CB CB prefix
//
// 27486 CB 7E BIT 7,(HL)
// 15925 CB 76 BIT 6,(HL)
// 13035 CB 19 RR C
// 11557 CB 7F BIT 7,A
// 10898 CB 37 SWAP A
// 10208 CB 66 BIT 4,(HL)
// Allows MWCW debugger to step through code properly
#ifdef CPU_BEGIN
CPU_BEGIN
#endif
#define TIME() s.time
#define CODE_PAGE( addr ) s.code_map [GB_CPU_PAGE( addr )]
#define READ_CODE( addr ) (CODE_PAGE( addr ) [GB_CPU_OFFSET( addr )])
// Flags with hex value for clarity when used as mask.
// Stored in indicated variable during emulation.
int const z80 = 0x80; // cz
int const n40 = 0x40; // ph
int const h20 = 0x20; // ph
int const c10 = 0x10; // cz
#define SET_FLAGS( in )\
{\
cz = ((in) << 4 & 0x100) + (~(in) >> 7 & 1);\
ph = (~(in) << 2 & 0x100) + ((in) >> 1 & 0x10);\
}
// random bits in cz to catch misuse of them
#define SET_FLAGS_DEBUG( in )\
{\
cz = ((in) << 4 & 0x100) | (rand() & ~0x1FF) | ((in) & 0x80 ? 0 : (rand() & 0xFF) | 1);\
ph = (~(in) << 2 & 0x100) | (((in) >> 1 & 0x10) ^ BYTE( cz ));\
}
#define GET_FLAGS( out )\
{\
out = (cz >> 4 & c10);\
out += ~ph >> 2 & n40;\
out += (ph ^ cz) << 1 & h20;\
if ( !BYTE( cz ) )\
out += z80;\
}
#define CC_NZ() ( BYTE( cz ))
#define CC_Z() (!BYTE( cz ))
#define CC_NC() (!(cz & 0x100))
#define CC_C() ( cz & 0x100 )
// Truncation
#define BYTE( n ) ((uint8_t ) (n)) /* (unsigned) n & 0xFF */
#define SBYTE( n ) ((int8_t ) (n)) /* (BYTE( n ) ^ 0x80) - 0x80 */
#define WORD( n ) ((uint16_t) (n)) /* (unsigned) n & 0xFFFF */
{
struct cpu_state_t s;
cpu->cpu_state = &s;
memcpy( &s, &cpu->cpu_state_, sizeof s );
union {
struct {
#ifdef BLARGG_BIG_ENDIAN
byte b, c, d, e, h, l, flags, a;
#else
byte c, b, e, d, l, h, a, flags;
#endif
} rg; // individual registers
struct core_regs_t rp; // pairs
byte r8_ [8]; // indexed registers (use R8 macro due to endian dependence)
uint16_t r16 [4]; // indexed pairs
} reg;
BOOST_STATIC_ASSERT( sizeof reg.rg == 8 && sizeof reg.rp == 8 );
#ifdef BLARGG_BIG_ENDIAN
#define R8( n ) (reg.r8_ [n])
#elif BLARGG_LITTLE_ENDIAN
#define R8( n ) (reg.r8_ [(n) ^ 1])
#else
// Be sure "blargg_endian.h" has been #included in the file that #includes this
#error "Byte order of CPU must be known"
#endif
#define R16( n ) (reg.r16 [n])
#define RG (reg.rg)
#define RP (reg.rp)
RP = cpu->r.rp;
int pc = cpu->r.pc;
int sp = cpu->r.sp;
int ph;
int cz;
SET_FLAGS( RG.flags );
int time = s.time;
loop:
check( (unsigned) pc < 0x10000 + 1 ); // +1 so emulator can catch wrap-around
check( (unsigned) sp < 0x10000 );
byte const* instr = CODE_PAGE( pc );
int op;
if ( GB_CPU_OFFSET(~0) == ~0 )
{
op = instr [pc];
pc++;
instr += pc;
}
else
{
instr += GB_CPU_OFFSET( pc );
op = *instr++;
pc++;
}
#define GET_ADDR() GET_LE16( instr )
static byte const instr_times [256*2] = {
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
4,12, 8, 8, 4, 4, 8, 4,20, 8, 8, 8, 4, 4, 8, 4,// 0
4,12, 8, 8, 4, 4, 8, 4,12, 8, 8, 8, 4, 4, 8, 4,// 1
8,12, 8, 8, 4, 4, 8, 4, 8, 8, 8, 8, 4, 4, 8, 4,// 2
8,12, 8, 8,12,12,12, 4, 8, 8, 8, 8, 4, 4, 8, 4,// 3
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// 4
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// 5
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// 6
8, 8, 8, 8, 8, 8, 0, 8, 4, 4, 4, 4, 4, 4, 8, 4,// 7
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// 8
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// 9
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// A
4, 4, 4, 4, 4, 4, 8, 4, 4, 4, 4, 4, 4, 4, 8, 4,// B
8,12,16,16,12,16, 8,16, 8,16,16, 0,12,24, 8,16,// C
8,12,16, 0,12,16, 8,16, 8,16,16, 0,12, 0, 8,16,// D
12,12, 8, 0, 0,16, 8,16,16, 4,16, 0, 0, 0, 8,16,// E
12,12, 8, 4, 0,16, 8,16,12, 8,16, 4, 0, 0, 8,16,// F
// CB prefixed
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 0
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 1
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 2
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 3
8, 8, 8, 8, 8, 8,12, 8, 8, 8, 8, 8, 8, 8,12, 8,// 4
8, 8, 8, 8, 8, 8,12, 8, 8, 8, 8, 8, 8, 8,12, 8,// 5
8, 8, 8, 8, 8, 8,12, 8, 8, 8, 8, 8, 8, 8,12, 8,// 6
8, 8, 8, 8, 8, 8,12, 8, 8, 8, 8, 8, 8, 8,12, 8,// 7
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 8
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// 9
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// A
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// B
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// C
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// D
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// E
8, 8, 8, 8, 8, 8,16, 8, 8, 8, 8, 8, 8, 8,16, 8,// F
};
if ( time >= 0 )
goto stop;
time += instr_times [op];
int data;
data = *instr;
s.time = time;
#ifdef CPU_INSTR_HOOK
{ CPU_INSTR_HOOK( (pc-1), (instr-1), rg.a, rp.bc, rp.de, rp.hl, sp ); }
#endif
switch ( op )
{
// TODO: more efficient way to handle negative branch that wraps PC around
#define BRANCH_( cond, clocks )\
{\
pc++;\
if ( !(cond) )\
goto loop;\
pc = WORD( pc + SBYTE( data ) );\
time += clocks;\
goto loop;\
}
#define BRANCH( cond ) BRANCH_( cond, 4 )
// Most Common
case 0x20: // JR NZ
BRANCH( CC_NZ() )
case 0x21: // LD HL,IMM (common)
RP.hl = GET_ADDR();
pc += 2;
goto loop;
case 0x28: // JR Z
BRANCH( CC_Z() )
case 0xF2: // LD A,(0xFF00+C)
READ_IO( this, RG.c, RG.a );
goto loop;
case 0xF0: // LD A,(0xFF00+imm)
pc++;
READ_IO( this, data, RG.a );
goto loop;
{
int temp;
case 0x0A: // LD A,(BC)
temp = RP.bc;
goto ld_a_ind_comm;
case 0x3A: // LD A,(HL-)
temp = RP.hl;
RP.hl = temp - 1;
goto ld_a_ind_comm;
case 0x1A: // LD A,(DE)
temp = RP.de;
goto ld_a_ind_comm;
case 0x2A: // LD A,(HL+) (common)
temp = RP.hl;
RP.hl = temp + 1;
goto ld_a_ind_comm;
case 0xFA: // LD A,IND16 (common)
temp = GET_ADDR();
pc += 2;
ld_a_ind_comm:
READ_FAST( this, temp, RG.a );
goto loop;
}
{
int temp;
case 0xBE: // CP (HL)
temp = READ_MEM( this, RP.hl );
goto cmp_comm;
case 0xB8: // CP B
case 0xB9: // CP C
case 0xBA: // CP D
case 0xBB: // CP E
case 0xBC: // CP H
case 0xBD: // CP L
case 0xBF: // CP A
temp = R8( op & 7 );
cmp_comm:
ph = RG.a ^ temp; // N=1 H=*
cz = RG.a - temp; // C=* Z=*
goto loop;
}
case 0xFE: // CP IMM
pc++;
ph = RG.a ^ data; // N=1 H=*
cz = RG.a - data; // C=* Z=*
goto loop;
case 0x46: // LD B,(HL)
case 0x4E: // LD C,(HL)
case 0x56: // LD D,(HL)
case 0x5E: // LD E,(HL)
case 0x66: // LD H,(HL)
case 0x6E: // LD L,(HL)
case 0x7E:{// LD A,(HL)
int addr = RP.hl;
READ_FAST( this, addr, R8( op >> 3 & 7 ) );
goto loop;
}
case 0xC4: // CNZ (next-most-common)
pc += 2;
if ( CC_Z() )
goto loop;
call:
time += 12;
pc -= 2;
case 0xCD: // CALL (most-common)
data = pc + 2;
pc = GET_ADDR();
push: {
int addr = WORD( sp - 1 );
WRITE_MEM( this, addr, (data >> 8) );
sp = WORD( sp - 2 );
WRITE_MEM( this, sp, data );
goto loop;
}
case 0xC8: // RET Z (next-most-common)
if ( CC_NZ() )
goto loop;
ret:
time += 12;
case 0xD9: // RETI
case 0xC9:{// RET (most common)
pc = READ_MEM( this, sp );
int addr = sp + 1;
sp = WORD( sp + 2 );
pc += 0x100 * READ_MEM( this, addr );
goto loop;
}
case 0x00: // NOP
case 0x40: // LD B,B
case 0x49: // LD C,C
case 0x52: // LD D,D
case 0x5B: // LD E,E
case 0x64: // LD H,H
case 0x6D: // LD L,L
case 0x7F: // LD A,A
goto loop;
// CB Instructions
case 0xCB:
time += (instr_times + 256) [data];
pc++;
// now data is the opcode
switch ( data ) {
case 0x46: // BIT b,(HL)
case 0x4E:
case 0x56:
case 0x5E:
case 0x66:
case 0x6E:
case 0x76:
case 0x7E: {
int addr = RP.hl;
READ_FAST( this, addr, op );
goto bit_comm;
}
case 0x40: case 0x41: case 0x42: case 0x43: // BIT b,r
case 0x44: case 0x45: case 0x47: case 0x48:
case 0x49: case 0x4A: case 0x4B: case 0x4C:
case 0x4D: case 0x4F: case 0x50: case 0x51:
case 0x52: case 0x53: case 0x54: case 0x55:
case 0x57: case 0x58: case 0x59: case 0x5A:
case 0x5B: case 0x5C: case 0x5D: case 0x5F:
case 0x60: case 0x61: case 0x62: case 0x63:
case 0x64: case 0x65: case 0x67: case 0x68:
case 0x69: case 0x6A: case 0x6B: case 0x6C:
case 0x6D: case 0x6F: case 0x70: case 0x71:
case 0x72: case 0x73: case 0x74: case 0x75:
case 0x77: case 0x78: case 0x79: case 0x7A:
case 0x7B: case 0x7C: case 0x7D: case 0x7F:
op = R8( data & 7 );
bit_comm:
ph = op >> (data >> 3 & 7) & 1;
cz = (cz & 0x100) + ph;
ph ^= 0x110; // N=0 H=1
goto loop;
case 0x86: // RES b,(HL)
case 0x8E:
case 0x96:
case 0x9E:
case 0xA6:
case 0xAE:
case 0xB6:
case 0xBE: {
int temp = READ_MEM( this, RP.hl );
temp &= ~(1 << (data >> 3 & 7));
WRITE_MEM( this, RP.hl, temp );
goto loop;
}
case 0xC6: // SET b,(HL)
case 0xCE:
case 0xD6:
case 0xDE:
case 0xE6:
case 0xEE:
case 0xF6:
case 0xFE: {
int temp = READ_MEM( this, RP.hl );
temp |= 1 << (data >> 3 & 7);
WRITE_MEM( this, RP.hl, temp );
goto loop;
}
case 0xC0: case 0xC1: case 0xC2: case 0xC3: // SET b,r
case 0xC4: case 0xC5: case 0xC7: case 0xC8:
case 0xC9: case 0xCA: case 0xCB: case 0xCC:
case 0xCD: case 0xCF: case 0xD0: case 0xD1:
case 0xD2: case 0xD3: case 0xD4: case 0xD5:
case 0xD7: case 0xD8: case 0xD9: case 0xDA:
case 0xDB: case 0xDC: case 0xDD: case 0xDF:
case 0xE0: case 0xE1: case 0xE2: case 0xE3:
case 0xE4: case 0xE5: case 0xE7: case 0xE8:
case 0xE9: case 0xEA: case 0xEB: case 0xEC:
case 0xED: case 0xEF: case 0xF0: case 0xF1:
case 0xF2: case 0xF3: case 0xF4: case 0xF5:
case 0xF7: case 0xF8: case 0xF9: case 0xFA:
case 0xFB: case 0xFC: case 0xFD: case 0xFF:
R8( data & 7 ) |= 1 << (data >> 3 & 7);
goto loop;
case 0x80: case 0x81: case 0x82: case 0x83: // RES b,r
case 0x84: case 0x85: case 0x87: case 0x88:
case 0x89: case 0x8A: case 0x8B: case 0x8C:
case 0x8D: case 0x8F: case 0x90: case 0x91:
case 0x92: case 0x93: case 0x94: case 0x95:
case 0x97: case 0x98: case 0x99: case 0x9A:
case 0x9B: case 0x9C: case 0x9D: case 0x9F:
case 0xA0: case 0xA1: case 0xA2: case 0xA3:
case 0xA4: case 0xA5: case 0xA7: case 0xA8:
case 0xA9: case 0xAA: case 0xAB: case 0xAC:
case 0xAD: case 0xAF: case 0xB0: case 0xB1:
case 0xB2: case 0xB3: case 0xB4: case 0xB5:
case 0xB7: case 0xB8: case 0xB9: case 0xBA:
case 0xBB: case 0xBC: case 0xBD: case 0xBF:
R8( data & 7 ) &= ~(1 << (data >> 3 & 7));
goto loop;
case 0x36: // SWAP (HL)
op = READ_MEM( this, RP.hl );
goto swap_comm;
case 0x30: // SWAP B
case 0x31: // SWAP C
case 0x32: // SWAP D
case 0x33: // SWAP E
case 0x34: // SWAP H
case 0x35: // SWAP L
case 0x37: // SWAP A
op = R8( data & 7 );
swap_comm:
op = (op >> 4) + (op << 4);
cz = BYTE( op );
ph = cz + 0x100;
if ( data == 0x36 )
goto write_hl_op_ff;
R8( data & 7 ) = op;
goto loop;
// Shift/Rotate
case 0x26: // SLA (HL)
cz = 0;
case 0x16: // RL (HL)
cz = (cz >> 8 & 1) + (READ_MEM( this, RP.hl ) << 1);
goto rl_hl_common;
case 0x06: // RLC (HL)
cz = READ_MEM( this, RP.hl );
cz = (cz << 1) + (cz >> 7 & 1);
rl_hl_common:
// Z=* C=*
ph = cz | 0x100; // N=0 H=0
WRITE_MEM( this, RP.hl, cz );
goto loop;
case 0x20: case 0x21: case 0x22: case 0x23: case 0x24: case 0x25: case 0x27: // SLA r
cz = 0;
case 0x10: case 0x11: case 0x12: case 0x13: case 0x14: case 0x15: case 0x17: // RL r
cz = (cz >> 8 & 1) + (R8( data & 7 ) << 1);
goto rl_common;
case 0x00: case 0x01: case 0x02: case 0x03: case 0x04: case 0x05: case 0x07: // RLC r
cz = R8( data & 7 );
cz = (cz << 1) + (cz >> 7 & 1);
rl_common:
// Z=* C=*
ph = cz | 0x100; // N=0 H=0
R8( data & 7 ) = cz;
goto loop;
case 0x0E: // RRC (HL)
cz = READ_MEM( this, RP.hl );
cz += cz << 8 & 0x100;
goto rr_hl_common;
case 0x2E: // SRA (HL)
cz = READ_MEM( this, RP.hl );
cz += cz << 1 & 0x100;
goto rr_hl_common;
case 0x3E: // SRL (HL)
cz = 0;
case 0x1E: // RR (HL)
cz = (cz & 0x100) + READ_MEM( this, RP.hl );
rr_hl_common:
cz = (cz << 8) + (cz >> 1); // Z=* C=*
ph = cz | 0x100; // N=0 H=0
WRITE_MEM( this, RP.hl, cz );
goto loop;
case 0x08: case 0x09: case 0x0A: case 0x0B: case 0x0C: case 0x0D: case 0x0F: // RRC r
cz = R8( data & 7 );
cz += cz << 8 & 0x100;
goto rr_common;
case 0x28: case 0x29: case 0x2A: case 0x2B: case 0x2C: case 0x2D: case 0x2F: // SRA r
cz = R8( data & 7 );
cz += cz << 1 & 0x100;
goto rr_common;
case 0x38: case 0x39: case 0x3A: case 0x3B: case 0x3C: case 0x3D: case 0x3F: // SRL r
cz = 0;
case 0x18: case 0x19: case 0x1A: case 0x1B: case 0x1C: case 0x1D: case 0x1F: // RR r
cz = (cz & 0x100) + R8( data & 7 );
rr_common:
cz = (cz << 8) + (cz >> 1); // Z=* C=*
ph = cz | 0x100; // N=0 H=0
R8( data & 7 ) = cz;
goto loop;
} // CB op
assert( false ); // unhandled CB op
case 0x07: // RLCA
cz = RG.a >> 7;
goto rlc_common;
case 0x17: // RLA
cz = cz >> 8 & 1;
rlc_common:
cz += RG.a << 1;
ph = cz | 0x100;
RG.a = BYTE( cz );
cz |= 1;
goto loop;
case 0x0F: // RRCA
ph = RG.a << 8;
goto rrc_common;
case 0x1F: // RRA
ph = cz;
rrc_common:
cz = (RG.a << 8) + 1; // Z=0 C=*
RG.a = ((ph & 0x100) + RG.a) >> 1;
ph = 0x100; // N=0 H=0
goto loop;
// Load
case 0x70: // LD (HL),B
case 0x71: // LD (HL),C
case 0x72: // LD (HL),D
case 0x73: // LD (HL),E
case 0x74: // LD (HL),H
case 0x75: // LD (HL),L
case 0x77: // LD (HL),A
op = R8( op & 7 );
write_hl_op_ff:
WRITE_MEM( this, RP.hl, op );
goto loop;
case 0x41: case 0x42: case 0x43: case 0x44: case 0x45: case 0x47: // LD r,r
case 0x48: case 0x4A: case 0x4B: case 0x4C: case 0x4D: case 0x4F:
case 0x50: case 0x51: case 0x53: case 0x54: case 0x55: case 0x57:
case 0x58: case 0x59: case 0x5A: case 0x5C: case 0x5D: case 0x5F:
case 0x60: case 0x61: case 0x62: case 0x63: case 0x65: case 0x67:
case 0x68: case 0x69: case 0x6A: case 0x6B: case 0x6C: case 0x6F:
case 0x78: case 0x79: case 0x7A: case 0x7B: case 0x7C: case 0x7D:
R8( op >> 3 & 7 ) = R8( op & 7 );
goto loop;
case 0x08: // LD IND16,SP
data = GET_ADDR();
pc += 2;
WRITE_MEM( this, data, sp );
data++;
WRITE_MEM( this, data, (sp >> 8) );
goto loop;
case 0xF9: // LD SP,HL
sp = RP.hl;
goto loop;
case 0x31: // LD SP,IMM
sp = GET_ADDR();
pc += 2;
goto loop;
case 0x01: // LD BC,IMM
case 0x11: // LD DE,IMM
R16( (unsigned) op >> 4 ) = GET_ADDR();
pc += 2;
goto loop;
case 0xE2: // LD (0xFF00+C),A
WRITE_IO( this, RG.c, RG.a );
goto loop;
case 0xE0: // LD (0xFF00+imm),A
pc++;
WRITE_IO( this, data, RG.a );
goto loop;
{
int temp;
case 0x32: // LD (HL-),A
temp = RP.hl;
RP.hl = temp - 1;
goto write_data_rg_a;
case 0x02: // LD (BC),A
temp = RP.bc;
goto write_data_rg_a;
case 0x12: // LD (DE),A
temp = RP.de;
goto write_data_rg_a;
case 0x22: // LD (HL+),A
temp = RP.hl;
RP.hl = temp + 1;
goto write_data_rg_a;
case 0xEA: // LD IND16,A (common)
temp = GET_ADDR();
pc += 2;
write_data_rg_a:
WRITE_MEM( this, temp, RG.a );
goto loop;
}
case 0x06: // LD B,IMM
RG.b = data;
pc++;
goto loop;
case 0x0E: // LD C,IMM
RG.c = data;
pc++;
goto loop;
case 0x16: // LD D,IMM
RG.d = data;
pc++;
goto loop;
case 0x1E: // LD E,IMM
RG.e = data;
pc++;
goto loop;
case 0x26: // LD H,IMM
RG.h = data;
pc++;
goto loop;
case 0x2E: // LD L,IMM
RG.l = data;
pc++;
goto loop;
case 0x36: // LD (HL),IMM
WRITE_MEM( this, RP.hl, data );
pc++;
goto loop;
case 0x3E: // LD A,IMM
RG.a = data;
pc++;
goto loop;
// Increment/decrement
case 0x03: // INC BC
case 0x13: // INC DE
case 0x23: // INC HL
R16( (unsigned) op >> 4 )++;
goto loop;
case 0x33: // INC SP
sp = WORD( sp + 1 );
goto loop;
case 0x0B: // DEC BC
case 0x1B: // DEC DE
case 0x2B: // DEC HL
R16( (unsigned) op >> 4 )--;
goto loop;
case 0x3B: // DEC SP
sp = WORD( sp - 1 );
goto loop;
case 0x34: // INC (HL)
op = RP.hl;
data = READ_MEM( this, op );
data++;
WRITE_MEM( this, op, data );
goto inc_comm;
case 0x04: // INC B
case 0x0C: // INC C (common)
case 0x14: // INC D
case 0x1C: // INC E
case 0x24: // INC H
case 0x2C: // INC L
case 0x3C: // INC A
op = op >> 3 & 7;
data = R8( op ) + 1;
R8( op ) = data;
inc_comm:
ph = data - 0x101; // N=0 H=*
cz = (cz & 0x100) + BYTE( data ); // C=- Z=*
goto loop;
case 0x35: // DEC (HL)
op = RP.hl;
data = READ_MEM( this, op );
data--;
WRITE_MEM( this, op, data );
goto dec_comm;
case 0x05: // DEC B
case 0x0D: // DEC C
case 0x15: // DEC D
case 0x1D: // DEC E
case 0x25: // DEC H
case 0x2D: // DEC L
case 0x3D: // DEC A
op = op >> 3 & 7;
data = R8( op ) - 1;
R8( op ) = data;
dec_comm:
ph = data + 1; // N=1 H=*
cz = (cz & 0x100) + BYTE( data ); // C=- Z=*
goto loop;
// Add 16-bit
case 0xF8: // LD HL,SP+n
case 0xE8:{// ADD SP,n
pc++;
int t = WORD( sp + SBYTE( data ) );
cz = ((BYTE( sp ) + data) & 0x100) + 1; // Z=0 C=*
ph = (sp ^ data ^ t) | 0x100; // N=0 H=*
if ( op == 0xF8 )
{
RP.hl = t;
goto loop;
}
sp = t;
goto loop;
}
case 0x39: // ADD HL,SP
data = sp;
goto add_hl_comm;
case 0x09: // ADD HL,BC
case 0x19: // ADD HL,DE
case 0x29: // ADD HL,HL
data = R16( (unsigned) op >> 4 );
add_hl_comm:
ph = RP.hl ^ data;
data += RP.hl;
RP.hl = WORD( data );
ph ^= data;
cz = BYTE( cz ) + (data >> 8 & 0x100); // C=* Z=-
ph = ((ph >> 8) ^ cz) | 0x100; // N=0 H=*
goto loop;
case 0x86: // ADD (HL)
data = READ_MEM( this, RP.hl );
goto add_comm;
case 0x80: // ADD B
case 0x81: // ADD C
case 0x82: // ADD D
case 0x83: // ADD E
case 0x84: // ADD H
case 0x85: // ADD L
case 0x87: // ADD A
data = R8( op & 7 );
goto add_comm;
case 0xC6: // ADD IMM
pc++;
add_comm:
ph = (RG.a ^ data) | 0x100; // N=1 H=*
cz = RG.a + data; // C=* Z=*
RG.a = cz;
goto loop;
// Add/Subtract
case 0x8E: // ADC (HL)
data = READ_MEM( this, RP.hl );
goto adc_comm;
case 0x88: // ADC B
case 0x89: // ADC C
case 0x8A: // ADC D
case 0x8B: // ADC E
case 0x8C: // ADC H
case 0x8D: // ADC L
case 0x8F: // ADC A
data = R8( op & 7 );
goto adc_comm;
case 0xCE: // ADC IMM
pc++;
adc_comm:
ph = (RG.a ^ data) | 0x100; // N=1 H=*
cz = RG.a + data + (cz >> 8 & 1); // C=* Z=*
RG.a = cz;
goto loop;
case 0x96: // SUB (HL)
data = READ_MEM( this, RP.hl );
goto sub_comm;
case 0x90: // SUB B
case 0x91: // SUB C
case 0x92: // SUB D
case 0x93: // SUB E
case 0x94: // SUB H
case 0x95: // SUB L
case 0x97: // SUB A
data = R8( op & 7 );
goto sub_comm;
case 0xD6: // SUB IMM
pc++;
sub_comm:
ph = RG.a ^ data; // N=1 H=*
cz = RG.a - data; // C=* Z=*
RG.a = cz;
goto loop;
case 0x9E: // SBC (HL)
data = READ_MEM( this, RP.hl );
goto sbc_comm;
case 0x98: // SBC B
case 0x99: // SBC C
case 0x9A: // SBC D
case 0x9B: // SBC E
case 0x9C: // SBC H
case 0x9D: // SBC L
case 0x9F: // SBC A
data = R8( op & 7 );
goto sbc_comm;
case 0xDE: // SBC IMM
pc++;
sbc_comm:
ph = RG.a ^ data; // N=1 H=*
cz = RG.a - data - (cz >> 8 & 1); // C=* Z=*
RG.a = cz;
goto loop;
// Logical
case 0xA0: // AND B
case 0xA1: // AND C
case 0xA2: // AND D
case 0xA3: // AND E
case 0xA4: // AND H
case 0xA5: // AND L
data = R8( op & 7 );
goto and_comm;
case 0xA6: // AND (HL)
data = READ_MEM( this, RP.hl );
goto and_comm;
case 0xE6: // AND IMM
pc++;
and_comm:
cz = RG.a & data; // C=0 Z=*
ph = ~cz; // N=0 H=1
RG.a = cz;
goto loop;
case 0xA7: // AND A
cz = RG.a; // C=0 Z=*
ph = ~RG.a; // N=0 H=1
goto loop;
case 0xB0: // OR B
case 0xB1: // OR C
case 0xB2: // OR D
case 0xB3: // OR E
case 0xB4: // OR H
case 0xB5: // OR L
data = R8( op & 7 );
goto or_comm;
case 0xB6: // OR (HL)
data = READ_MEM( this, RP.hl );
goto or_comm;
case 0xF6: // OR IMM
pc++;
or_comm:
cz = RG.a | data; // C=0 Z=*
ph = cz | 0x100; // N=0 H=0
RG.a = cz;
goto loop;
case 0xB7: // OR A
cz = RG.a; // C=0 Z=*
ph = RG.a + 0x100; // N=0 H=0
goto loop;
case 0xA8: // XOR B
case 0xA9: // XOR C
case 0xAA: // XOR D
case 0xAB: // XOR E
case 0xAC: // XOR H
case 0xAD: // XOR L
data = R8( op & 7 );
goto xor_comm;
case 0xAE: // XOR (HL)
data = READ_MEM( this, RP.hl );
pc--;
case 0xEE: // XOR IMM
pc++;
xor_comm:
cz = RG.a ^ data; // C=0 Z=*
ph = cz + 0x100; // N=0 H=0
RG.a = cz;
goto loop;
case 0xAF: // XOR A
RG.a = 0;
cz = 0; // C=0 Z=*
ph = 0x100; // N=0 H=0
goto loop;
// Stack
case 0xF1: // POP AF
case 0xC1: // POP BC
case 0xD1: // POP DE
case 0xE1: // POP HL (common)
data = READ_MEM( this, sp );
R16( op >> 4 & 3 ) = data + 0x100 * READ_MEM( this, (sp + 1) );
sp = WORD( sp + 2 );
if ( op != 0xF1 )
goto loop;
SET_FLAGS( RG.a );
RG.a = RG.flags;
goto loop;
case 0xC5: // PUSH BC
data = RP.bc;
goto push;
case 0xD5: // PUSH DE
data = RP.de;
goto push;
case 0xE5: // PUSH HL
data = RP.hl;
goto push;
case 0xF5: // PUSH AF
GET_FLAGS( data );
data += RG.a << 8;
goto push;
// Flow control
case 0xFF: case 0xC7: case 0xCF: case 0xD7: // RST
case 0xDF: case 0xE7: case 0xEF: case 0xF7:
data = pc;
pc = (op & 0x38) + cpu->rst_base;
goto push;
case 0xCC: // CALL Z
pc += 2;
if ( CC_Z() )
goto call;
goto loop;
case 0xD4: // CALL NC
pc += 2;
if ( CC_NC() )
goto call;
goto loop;
case 0xDC: // CALL C
pc += 2;
if ( CC_C() )
goto call;
goto loop;
case 0xC0: // RET NZ
if ( CC_NZ() )
goto ret;
goto loop;
case 0xD0: // RET NC
if ( CC_NC() )
goto ret;
goto loop;
case 0xD8: // RET C
if ( CC_C() )
goto ret;
goto loop;
case 0x18: // JR
BRANCH_( true, 0 )
case 0x30: // JR NC
BRANCH( CC_NC() )
case 0x38: // JR C
BRANCH( CC_C() )
case 0xE9: // LD PC,HL
pc = RP.hl;
goto loop;
case 0xC3: // JP (next-most-common)
pc = GET_ADDR();
goto loop;
case 0xC2: // JP NZ
pc += 2;
if ( CC_NZ() )
goto jp_taken;
time -= 4;
goto loop;
case 0xCA: // JP Z (most common)
pc += 2;
if ( CC_Z() )
goto jp_taken;
time -= 4;
goto loop;
jp_taken:
pc -= 2;
pc = GET_ADDR();
goto loop;
case 0xD2: // JP NC
pc += 2;
if ( CC_NC() )
goto jp_taken;
time -= 4;
goto loop;
case 0xDA: // JP C
pc += 2;
if ( CC_C() )
goto jp_taken;
time -= 4;
goto loop;
// Flags
case 0x2F: // CPL
RG.a = ~RG.a;
ph = BYTE( ~cz ); // N=1 H=1
goto loop;
case 0x3F: // CCF
ph = cz | 0x100; // N=0 H=0
cz ^= 0x100; // C=* Z=-
goto loop;
case 0x37: // SCF
ph = cz | 0x100; // N=0 H=0
cz |= 0x100; // C=1 Z=-
goto loop;
case 0xF3: // DI
goto loop;
case 0xFB: // EI
goto loop;
case 0x27:{// DAA
unsigned a = RG.a;
int h = ph ^ cz;
if ( ph & 0x100 )
{
if ( (h & 0x10) || (a & 0x0F) > 9 )
a += 6;
if ( (cz & 0x100) || a > 0x9F )
a += 0x60;
}
else
{
if ( h & 0x10 )
a = (a - 6) & 0xFF;
if ( cz & 0x100 )
a -= 0x60;
}
cz = (cz & 0x100) | a; // C=- Z=*
RG.a = a;
ph = (ph & 0x100) + BYTE( a ); // N=- H=0
goto loop;
}
// Special
case 0x76: // HALT
case 0x10: // STOP
case 0xD3: case 0xDB: case 0xDD: // Illegal
case 0xE3: case 0xE4: case 0xEB: case 0xEC: case 0xED: // (all freeze cpu)
case 0xF4: case 0xFC: case 0xFD:
goto stop;
}
// If this fails then an opcode isn't handled above
assert( false );
stop:
pc--;
// copy state back
cpu->cpu_state_.time = time;
cpu->r.pc = pc;
cpu->r.sp = sp;
{
int t;
GET_FLAGS( t );
RG.flags = t;
}
cpu->cpu_state = &cpu->cpu_state_;
cpu->r.rp = RP;
}