SRB2/libs/gme/gme/Spc_Cpu.h
2018-12-30 22:49:11 -05:00

1221 lines
23 KiB
C

// Game_Music_Emu 0.6.0. http://www.slack.net/~ant/
/* Copyright (C) 2004-2007 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 */
//// Memory access
#if SPC_MORE_ACCURACY
#define SUSPICIOUS_OPCODE( name ) ((void) 0)
#else
#define SUSPICIOUS_OPCODE( name ) debug_printf( "SPC: suspicious opcode: " name "\n" )
#endif
#define CPU_READ( time, offset, addr )\
cpu_read( addr, time + offset )
#define CPU_WRITE( time, offset, addr, data )\
cpu_write( data, addr, time + offset )
#if SPC_MORE_ACCURACY
#define CPU_READ_TIMER( time, offset, addr, out )\
{ out = CPU_READ( time, offset, addr ); }
#else
// timers are by far the most common thing read from dp
#define CPU_READ_TIMER( time, offset, addr_, out )\
{\
rel_time_t adj_time = time + offset;\
int dp_addr = addr_;\
int ti = dp_addr - (r_t0out + 0xF0);\
if ( (unsigned) ti < timer_count )\
{\
Timer* t = &m.timers [ti];\
if ( adj_time >= t->next_time )\
t = run_timer_( t, adj_time );\
out = t->counter;\
t->counter = 0;\
}\
else\
{\
out = ram [dp_addr];\
int i = dp_addr - 0xF0;\
if ( (unsigned) i < 0x10 )\
out = cpu_read_smp_reg( i, adj_time );\
}\
}
#endif
#define TIME_ADJ( n ) (n)
#define READ_TIMER( time, addr, out ) CPU_READ_TIMER( rel_time, TIME_ADJ(time), (addr), out )
#define READ( time, addr ) CPU_READ ( rel_time, TIME_ADJ(time), (addr) )
#define WRITE( time, addr, data ) CPU_WRITE( rel_time, TIME_ADJ(time), (addr), (data) )
#define DP_ADDR( addr ) (dp + (addr))
#define READ_DP_TIMER( time, addr, out ) CPU_READ_TIMER( rel_time, TIME_ADJ(time), DP_ADDR( addr ), out )
#define READ_DP( time, addr ) READ ( time, DP_ADDR( addr ) )
#define WRITE_DP( time, addr, data ) WRITE( time, DP_ADDR( addr ), data )
#define READ_PROG16( addr ) GET_LE16( ram + (addr) )
#define SET_PC( n ) (pc = ram + (n))
#define GET_PC() (pc - ram)
#define READ_PC( pc ) (*(pc))
#define READ_PC16( pc ) GET_LE16( pc )
// TODO: remove non-wrapping versions?
#define SPC_NO_SP_WRAPAROUND 0
#define SET_SP( v ) (sp = ram + 0x101 + ((uint8_t) v))
#define GET_SP() (uint8_t (sp - 0x101 - ram))
#if SPC_NO_SP_WRAPAROUND
#define PUSH16( v ) (sp -= 2, SET_LE16( sp, v ))
#define PUSH( v ) (void) (*--sp = (uint8_t) (v))
#define POP( out ) (void) ((out) = *sp++)
#else
#define PUSH16( data )\
{\
int addr = (sp -= 2) - ram;\
if ( addr > 0x100 )\
{\
SET_LE16( sp, data );\
}\
else\
{\
ram [(uint8_t) addr + 0x100] = (uint8_t) data;\
sp [1] = (uint8_t) (data >> 8);\
sp += 0x100;\
}\
}
#define PUSH( data )\
{\
*--sp = (uint8_t) (data);\
if ( sp - ram == 0x100 )\
sp += 0x100;\
}
#define POP( out )\
{\
out = *sp++;\
if ( sp - ram == 0x201 )\
{\
out = sp [-0x101];\
sp -= 0x100;\
}\
}
#endif
#define MEM_BIT( rel ) CPU_mem_bit( pc, rel_time + rel )
unsigned Snes_Spc::CPU_mem_bit( uint8_t const* pc, rel_time_t rel_time )
{
unsigned addr = READ_PC16( pc );
unsigned t = READ( 0, addr & 0x1FFF ) >> (addr >> 13);
return t << 8 & 0x100;
}
//// Status flag handling
// Hex value in name to clarify code and bit shifting.
// Flag stored in indicated variable during emulation
int const n80 = 0x80; // nz
int const v40 = 0x40; // psw
int const p20 = 0x20; // dp
int const b10 = 0x10; // psw
int const h08 = 0x08; // psw
int const i04 = 0x04; // psw
int const z02 = 0x02; // nz
int const c01 = 0x01; // c
int const nz_neg_mask = 0x880; // either bit set indicates N flag set
#define GET_PSW( out )\
{\
out = psw & ~(n80 | p20 | z02 | c01);\
out |= c >> 8 & c01;\
out |= dp >> 3 & p20;\
out |= ((nz >> 4) | nz) & n80;\
if ( !(uint8_t) nz ) out |= z02;\
}
#define SET_PSW( in )\
{\
psw = in;\
c = in << 8;\
dp = in << 3 & 0x100;\
nz = (in << 4 & 0x800) | (~in & z02);\
}
SPC_CPU_RUN_FUNC
{
uint8_t* const ram = RAM;
int a = m.cpu_regs.a;
int x = m.cpu_regs.x;
int y = m.cpu_regs.y;
uint8_t const* pc;
uint8_t* sp;
int psw;
int c;
int nz;
int dp;
SET_PC( m.cpu_regs.pc );
SET_SP( m.cpu_regs.sp );
SET_PSW( m.cpu_regs.psw );
goto loop;
// Main loop
cbranch_taken_loop:
pc += *(BOOST::int8_t const*) pc;
inc_pc_loop:
pc++;
loop:
{
unsigned opcode;
unsigned data;
check( (unsigned) a < 0x100 );
check( (unsigned) x < 0x100 );
check( (unsigned) y < 0x100 );
opcode = *pc;
if ( (rel_time += m.cycle_table [opcode]) > 0 )
goto out_of_time;
#ifdef SPC_CPU_OPCODE_HOOK
SPC_CPU_OPCODE_HOOK( GET_PC(), opcode );
#endif
/*
//SUB_CASE_COUNTER( 1 );
#define PROFILE_TIMER_LOOP( op, addr, len )\
if ( opcode == op )\
{\
int cond = (unsigned) ((addr) - 0xFD) < 3 &&\
pc [len] == 0xF0 && pc [len+1] == 0xFE - len;\
SUB_CASE_COUNTER( op && cond );\
}
PROFILE_TIMER_LOOP( 0xEC, GET_LE16( pc + 1 ), 3 );
PROFILE_TIMER_LOOP( 0xEB, pc [1], 2 );
PROFILE_TIMER_LOOP( 0xE4, pc [1], 2 );
*/
// TODO: if PC is at end of memory, this will get wrong operand (very obscure)
data = *++pc;
switch ( opcode )
{
// Common instructions
#define BRANCH( cond )\
{\
pc++;\
pc += (BOOST::int8_t) data;\
if ( cond )\
goto loop;\
pc -= (BOOST::int8_t) data;\
rel_time -= 2;\
goto loop;\
}
case 0xF0: // BEQ
BRANCH( !(uint8_t) nz ) // 89% taken
case 0xD0: // BNE
BRANCH( (uint8_t) nz )
case 0x3F:{// CALL
int old_addr = GET_PC() + 2;
SET_PC( READ_PC16( pc ) );
PUSH16( old_addr );
goto loop;
}
case 0x6F:// RET
#if SPC_NO_SP_WRAPAROUND
{
SET_PC( GET_LE16( sp ) );
sp += 2;
}
#else
{
int addr = sp - ram;
SET_PC( GET_LE16( sp ) );
sp += 2;
if ( addr < 0x1FF )
goto loop;
SET_PC( sp [-0x101] * 0x100 + ram [(uint8_t) addr + 0x100] );
sp -= 0x100;
}
#endif
goto loop;
case 0xE4: // MOV a,dp
++pc;
// 80% from timer
READ_DP_TIMER( 0, data, a = nz );
goto loop;
case 0xFA:{// MOV dp,dp
int temp;
READ_DP_TIMER( -2, data, temp );
data = temp + no_read_before_write ;
}
// fall through
case 0x8F:{// MOV dp,#imm
int temp = READ_PC( pc + 1 );
pc += 2;
#if !SPC_MORE_ACCURACY
{
int i = dp + temp;
ram [i] = (uint8_t) data;
i -= 0xF0;
if ( (unsigned) i < 0x10 ) // 76%
{
REGS [i] = (uint8_t) data;
// Registers other than $F2 and $F4-$F7
//if ( i != 2 && i != 4 && i != 5 && i != 6 && i != 7 )
if ( ((~0x2F00 << (bits_in_int - 16)) << i) < 0 ) // 12%
cpu_write_smp_reg( data, rel_time, i );
}
}
#else
WRITE_DP( 0, temp, data );
#endif
goto loop;
}
case 0xC4: // MOV dp,a
++pc;
#if !SPC_MORE_ACCURACY
{
int i = dp + data;
ram [i] = (uint8_t) a;
i -= 0xF0;
if ( (unsigned) i < 0x10 ) // 39%
{
unsigned sel = i - 2;
REGS [i] = (uint8_t) a;
if ( sel == 1 ) // 51% $F3
dsp_write( a, rel_time );
else if ( sel > 1 ) // 1% not $F2 or $F3
cpu_write_smp_reg_( a, rel_time, i );
}
}
#else
WRITE_DP( 0, data, a );
#endif
goto loop;
#define CASE( n ) case n:
// Define common address modes based on opcode for immediate mode. Execution
// ends with data set to the address of the operand.
#define ADDR_MODES_( op )\
CASE( op - 0x02 ) /* (X) */\
data = x + dp;\
pc--;\
goto end_##op;\
CASE( op + 0x0F ) /* (dp)+Y */\
data = READ_PROG16( data + dp ) + y;\
goto end_##op;\
CASE( op - 0x01 ) /* (dp+X) */\
data = READ_PROG16( ((uint8_t) (data + x)) + dp );\
goto end_##op;\
CASE( op + 0x0E ) /* abs+Y */\
data += y;\
goto abs_##op;\
CASE( op + 0x0D ) /* abs+X */\
data += x;\
CASE( op - 0x03 ) /* abs */\
abs_##op:\
data += 0x100 * READ_PC( ++pc );\
goto end_##op;\
CASE( op + 0x0C ) /* dp+X */\
data = (uint8_t) (data + x);
#define ADDR_MODES_NO_DP( op )\
ADDR_MODES_( op )\
data += dp;\
end_##op:
#define ADDR_MODES( op )\
ADDR_MODES_( op )\
CASE( op - 0x04 ) /* dp */\
data += dp;\
end_##op:
// 1. 8-bit Data Transmission Commands. Group I
ADDR_MODES_NO_DP( 0xE8 ) // MOV A,addr
a = nz = READ( 0, data );
goto inc_pc_loop;
case 0xBF:{// MOV A,(X)+
int temp = x + dp;
x = (uint8_t) (x + 1);
a = nz = READ( -1, temp );
goto loop;
}
case 0xE8: // MOV A,imm
a = data;
nz = data;
goto inc_pc_loop;
case 0xF9: // MOV X,dp+Y
data = (uint8_t) (data + y);
case 0xF8: // MOV X,dp
READ_DP_TIMER( 0, data, x = nz );
goto inc_pc_loop;
case 0xE9: // MOV X,abs
data = READ_PC16( pc );
++pc;
data = READ( 0, data );
case 0xCD: // MOV X,imm
x = data;
nz = data;
goto inc_pc_loop;
case 0xFB: // MOV Y,dp+X
data = (uint8_t) (data + x);
case 0xEB: // MOV Y,dp
// 70% from timer
pc++;
READ_DP_TIMER( 0, data, y = nz );
goto loop;
case 0xEC:{// MOV Y,abs
int temp = READ_PC16( pc );
pc += 2;
READ_TIMER( 0, temp, y = nz );
//y = nz = READ( 0, temp );
goto loop;
}
case 0x8D: // MOV Y,imm
y = data;
nz = data;
goto inc_pc_loop;
// 2. 8-BIT DATA TRANSMISSION COMMANDS, GROUP 2
ADDR_MODES_NO_DP( 0xC8 ) // MOV addr,A
WRITE( 0, data, a );
goto inc_pc_loop;
{
int temp;
case 0xCC: // MOV abs,Y
temp = y;
goto mov_abs_temp;
case 0xC9: // MOV abs,X
temp = x;
mov_abs_temp:
WRITE( 0, READ_PC16( pc ), temp );
pc += 2;
goto loop;
}
case 0xD9: // MOV dp+Y,X
data = (uint8_t) (data + y);
case 0xD8: // MOV dp,X
WRITE( 0, data + dp, x );
goto inc_pc_loop;
case 0xDB: // MOV dp+X,Y
data = (uint8_t) (data + x);
case 0xCB: // MOV dp,Y
WRITE( 0, data + dp, y );
goto inc_pc_loop;
// 3. 8-BIT DATA TRANSMISSIN COMMANDS, GROUP 3.
case 0x7D: // MOV A,X
a = x;
nz = x;
goto loop;
case 0xDD: // MOV A,Y
a = y;
nz = y;
goto loop;
case 0x5D: // MOV X,A
x = a;
nz = a;
goto loop;
case 0xFD: // MOV Y,A
y = a;
nz = a;
goto loop;
case 0x9D: // MOV X,SP
x = nz = GET_SP();
goto loop;
case 0xBD: // MOV SP,X
SET_SP( x );
goto loop;
//case 0xC6: // MOV (X),A (handled by MOV addr,A in group 2)
case 0xAF: // MOV (X)+,A
WRITE_DP( 0, x, a + no_read_before_write );
x = (uint8_t) (x + 1);
goto loop;
// 5. 8-BIT LOGIC OPERATION COMMANDS
#define LOGICAL_OP( op, func )\
ADDR_MODES( op ) /* addr */\
data = READ( 0, data );\
case op: /* imm */\
nz = a func##= data;\
goto inc_pc_loop;\
{ unsigned addr;\
case op + 0x11: /* X,Y */\
data = READ_DP( -2, y );\
addr = x + dp;\
goto addr_##op;\
case op + 0x01: /* dp,dp */\
data = READ_DP( -3, data );\
case op + 0x10:{/*dp,imm*/\
uint8_t const* addr2 = pc + 1;\
pc += 2;\
addr = READ_PC( addr2 ) + dp;\
}\
addr_##op:\
nz = data func READ( -1, addr );\
WRITE( 0, addr, nz );\
goto loop;\
}
LOGICAL_OP( 0x28, & ); // AND
LOGICAL_OP( 0x08, | ); // OR
LOGICAL_OP( 0x48, ^ ); // EOR
// 4. 8-BIT ARITHMETIC OPERATION COMMANDS
ADDR_MODES( 0x68 ) // CMP addr
data = READ( 0, data );
case 0x68: // CMP imm
nz = a - data;
c = ~nz;
nz &= 0xFF;
goto inc_pc_loop;
case 0x79: // CMP (X),(Y)
data = READ_DP( -2, y );
nz = READ_DP( -1, x ) - data;
c = ~nz;
nz &= 0xFF;
goto loop;
case 0x69: // CMP dp,dp
data = READ_DP( -3, data );
case 0x78: // CMP dp,imm
nz = READ_DP( -1, READ_PC( ++pc ) ) - data;
c = ~nz;
nz &= 0xFF;
goto inc_pc_loop;
case 0x3E: // CMP X,dp
data += dp;
goto cmp_x_addr;
case 0x1E: // CMP X,abs
data = READ_PC16( pc );
pc++;
cmp_x_addr:
data = READ( 0, data );
case 0xC8: // CMP X,imm
nz = x - data;
c = ~nz;
nz &= 0xFF;
goto inc_pc_loop;
case 0x7E: // CMP Y,dp
data += dp;
goto cmp_y_addr;
case 0x5E: // CMP Y,abs
data = READ_PC16( pc );
pc++;
cmp_y_addr:
data = READ( 0, data );
case 0xAD: // CMP Y,imm
nz = y - data;
c = ~nz;
nz &= 0xFF;
goto inc_pc_loop;
{
int addr;
case 0xB9: // SBC (x),(y)
case 0x99: // ADC (x),(y)
pc--; // compensate for inc later
data = READ_DP( -2, y );
addr = x + dp;
goto adc_addr;
case 0xA9: // SBC dp,dp
case 0x89: // ADC dp,dp
data = READ_DP( -3, data );
case 0xB8: // SBC dp,imm
case 0x98: // ADC dp,imm
addr = READ_PC( ++pc ) + dp;
adc_addr:
nz = READ( -1, addr );
goto adc_data;
// catch ADC and SBC together, then decode later based on operand
#undef CASE
#define CASE( n ) case n: case (n) + 0x20:
ADDR_MODES( 0x88 ) // ADC/SBC addr
data = READ( 0, data );
case 0xA8: // SBC imm
case 0x88: // ADC imm
addr = -1; // A
nz = a;
adc_data: {
int flags;
if ( opcode >= 0xA0 ) // SBC
data ^= 0xFF;
flags = data ^ nz;
nz += data + (c >> 8 & 1);
flags ^= nz;
psw = (psw & ~(v40 | h08)) |
(flags >> 1 & h08) |
((flags + 0x80) >> 2 & v40);
c = nz;
if ( addr < 0 )
{
a = (uint8_t) nz;
goto inc_pc_loop;
}
WRITE( 0, addr, /*(uint8_t)*/ nz );
goto inc_pc_loop;
}
}
// 6. ADDITION & SUBTRACTION COMMANDS
#define INC_DEC_REG( reg, op )\
nz = reg op;\
reg = (uint8_t) nz;\
goto loop;
case 0xBC: INC_DEC_REG( a, + 1 ) // INC A
case 0x3D: INC_DEC_REG( x, + 1 ) // INC X
case 0xFC: INC_DEC_REG( y, + 1 ) // INC Y
case 0x9C: INC_DEC_REG( a, - 1 ) // DEC A
case 0x1D: INC_DEC_REG( x, - 1 ) // DEC X
case 0xDC: INC_DEC_REG( y, - 1 ) // DEC Y
case 0x9B: // DEC dp+X
case 0xBB: // INC dp+X
data = (uint8_t) (data + x);
case 0x8B: // DEC dp
case 0xAB: // INC dp
data += dp;
goto inc_abs;
case 0x8C: // DEC abs
case 0xAC: // INC abs
data = READ_PC16( pc );
pc++;
inc_abs:
nz = (opcode >> 4 & 2) - 1;
nz += READ( -1, data );
WRITE( 0, data, /*(uint8_t)*/ nz );
goto inc_pc_loop;
// 7. SHIFT, ROTATION COMMANDS
case 0x5C: // LSR A
c = 0;
case 0x7C:{// ROR A
nz = (c >> 1 & 0x80) | (a >> 1);
c = a << 8;
a = nz;
goto loop;
}
case 0x1C: // ASL A
c = 0;
case 0x3C:{// ROL A
int temp = c >> 8 & 1;
c = a << 1;
nz = c | temp;
a = (uint8_t) nz;
goto loop;
}
case 0x0B: // ASL dp
c = 0;
data += dp;
goto rol_mem;
case 0x1B: // ASL dp+X
c = 0;
case 0x3B: // ROL dp+X
data = (uint8_t) (data + x);
case 0x2B: // ROL dp
data += dp;
goto rol_mem;
case 0x0C: // ASL abs
c = 0;
case 0x2C: // ROL abs
data = READ_PC16( pc );
pc++;
rol_mem:
nz = c >> 8 & 1;
nz |= (c = READ( -1, data ) << 1);
WRITE( 0, data, /*(uint8_t)*/ nz );
goto inc_pc_loop;
case 0x4B: // LSR dp
c = 0;
data += dp;
goto ror_mem;
case 0x5B: // LSR dp+X
c = 0;
case 0x7B: // ROR dp+X
data = (uint8_t) (data + x);
case 0x6B: // ROR dp
data += dp;
goto ror_mem;
case 0x4C: // LSR abs
c = 0;
case 0x6C: // ROR abs
data = READ_PC16( pc );
pc++;
ror_mem: {
int temp = READ( -1, data );
nz = (c >> 1 & 0x80) | (temp >> 1);
c = temp << 8;
WRITE( 0, data, nz );
goto inc_pc_loop;
}
case 0x9F: // XCN
nz = a = (a >> 4) | (uint8_t) (a << 4);
goto loop;
// 8. 16-BIT TRANSMISION COMMANDS
case 0xBA: // MOVW YA,dp
a = READ_DP( -2, data );
nz = (a & 0x7F) | (a >> 1);
y = READ_DP( 0, (uint8_t) (data + 1) );
nz |= y;
goto inc_pc_loop;
case 0xDA: // MOVW dp,YA
WRITE_DP( -1, data, a );
WRITE_DP( 0, (uint8_t) (data + 1), y + no_read_before_write );
goto inc_pc_loop;
// 9. 16-BIT OPERATION COMMANDS
case 0x3A: // INCW dp
case 0x1A:{// DECW dp
int temp;
// low byte
data += dp;
temp = READ( -3, data );
temp += (opcode >> 4 & 2) - 1; // +1 for INCW, -1 for DECW
nz = ((temp >> 1) | temp) & 0x7F;
WRITE( -2, data, /*(uint8_t)*/ temp );
// high byte
data = (uint8_t) (data + 1) + dp;
temp = (uint8_t) ((temp >> 8) + READ( -1, data ));
nz |= temp;
WRITE( 0, data, temp );
goto inc_pc_loop;
}
case 0x7A: // ADDW YA,dp
case 0x9A:{// SUBW YA,dp
int lo = READ_DP( -2, data );
int hi = READ_DP( 0, (uint8_t) (data + 1) );
int result;
int flags;
if ( opcode == 0x9A ) // SUBW
{
lo = (lo ^ 0xFF) + 1;
hi ^= 0xFF;
}
lo += a;
result = y + hi + (lo >> 8);
flags = hi ^ y ^ result;
psw = (psw & ~(v40 | h08)) |
(flags >> 1 & h08) |
((flags + 0x80) >> 2 & v40);
c = result;
a = (uint8_t) lo;
result = (uint8_t) result;
y = result;
nz = (((lo >> 1) | lo) & 0x7F) | result;
goto inc_pc_loop;
}
case 0x5A: { // CMPW YA,dp
int temp = a - READ_DP( -1, data );
nz = ((temp >> 1) | temp) & 0x7F;
temp = y + (temp >> 8);
temp -= READ_DP( 0, (uint8_t) (data + 1) );
nz |= temp;
c = ~temp;
nz &= 0xFF;
goto inc_pc_loop;
}
// 10. MULTIPLICATION & DIVISON COMMANDS
case 0xCF: { // MUL YA
unsigned temp = y * a;
a = (uint8_t) temp;
nz = ((temp >> 1) | temp) & 0x7F;
y = (uint8_t) (temp >> 8);
nz |= y;
goto loop;
}
case 0x9E: // DIV YA,X
{
unsigned ya = y * 0x100 + a;
psw &= ~(h08 | v40);
if ( y >= x )
psw |= v40;
if ( (y & 15) >= (x & 15) )
psw |= h08;
if ( y < x * 2 )
{
a = ya / x;
y = ya - a * x;
}
else
{
a = 255 - (ya - x * 0x200) / (256 - x);
y = x + (ya - x * 0x200) % (256 - x);
}
nz = (uint8_t) a;
a = (uint8_t) a;
y = (uint8_t) y;
goto loop;
}
// 11. DECIMAL COMPENSATION COMMANDS
case 0xDF: // DAA
SUSPICIOUS_OPCODE( "DAA" );
if ( a > 0x99 || c & 0x100 )
{
a += 0x60;
c = 0x100;
}
if ( (a & 0x0F) > 9 || psw & h08 )
a += 0x06;
nz = a;
a = (uint8_t) a;
goto loop;
case 0xBE: // DAS
SUSPICIOUS_OPCODE( "DAS" );
if ( a > 0x99 || !(c & 0x100) )
{
a -= 0x60;
c = 0;
}
if ( (a & 0x0F) > 9 || !(psw & h08) )
a -= 0x06;
nz = a;
a = (uint8_t) a;
goto loop;
// 12. BRANCHING COMMANDS
case 0x2F: // BRA rel
pc += (BOOST::int8_t) data;
goto inc_pc_loop;
case 0x30: // BMI
BRANCH( (nz & nz_neg_mask) )
case 0x10: // BPL
BRANCH( !(nz & nz_neg_mask) )
case 0xB0: // BCS
BRANCH( c & 0x100 )
case 0x90: // BCC
BRANCH( !(c & 0x100) )
case 0x70: // BVS
BRANCH( psw & v40 )
case 0x50: // BVC
BRANCH( !(psw & v40) )
#define CBRANCH( cond )\
{\
pc++;\
if ( cond )\
goto cbranch_taken_loop;\
rel_time -= 2;\
goto inc_pc_loop;\
}
case 0x03: // BBS dp.bit,rel
case 0x23:
case 0x43:
case 0x63:
case 0x83:
case 0xA3:
case 0xC3:
case 0xE3:
CBRANCH( READ_DP( -4, data ) >> (opcode >> 5) & 1 )
case 0x13: // BBC dp.bit,rel
case 0x33:
case 0x53:
case 0x73:
case 0x93:
case 0xB3:
case 0xD3:
case 0xF3:
CBRANCH( !(READ_DP( -4, data ) >> (opcode >> 5) & 1) )
case 0xDE: // CBNE dp+X,rel
data = (uint8_t) (data + x);
// fall through
case 0x2E:{// CBNE dp,rel
int temp;
// 61% from timer
READ_DP_TIMER( -4, data, temp );
CBRANCH( temp != a )
}
case 0x6E: { // DBNZ dp,rel
unsigned temp = READ_DP( -4, data ) - 1;
WRITE_DP( -3, (uint8_t) data, /*(uint8_t)*/ temp + no_read_before_write );
CBRANCH( temp )
}
case 0xFE: // DBNZ Y,rel
y = (uint8_t) (y - 1);
BRANCH( y )
case 0x1F: // JMP [abs+X]
SET_PC( READ_PC16( pc ) + x );
// fall through
case 0x5F: // JMP abs
SET_PC( READ_PC16( pc ) );
goto loop;
// 13. SUB-ROUTINE CALL RETURN COMMANDS
case 0x0F:{// BRK
int temp;
int ret_addr = GET_PC();
SUSPICIOUS_OPCODE( "BRK" );
SET_PC( READ_PROG16( 0xFFDE ) ); // vector address verified
PUSH16( ret_addr );
GET_PSW( temp );
psw = (psw | b10) & ~i04;
PUSH( temp );
goto loop;
}
case 0x4F:{// PCALL offset
int ret_addr = GET_PC() + 1;
SET_PC( 0xFF00 | data );
PUSH16( ret_addr );
goto loop;
}
case 0x01: // TCALL n
case 0x11:
case 0x21:
case 0x31:
case 0x41:
case 0x51:
case 0x61:
case 0x71:
case 0x81:
case 0x91:
case 0xA1:
case 0xB1:
case 0xC1:
case 0xD1:
case 0xE1:
case 0xF1: {
int ret_addr = GET_PC();
SET_PC( READ_PROG16( 0xFFDE - (opcode >> 3) ) );
PUSH16( ret_addr );
goto loop;
}
// 14. STACK OPERATION COMMANDS
{
int temp;
case 0x7F: // RET1
temp = *sp;
SET_PC( GET_LE16( sp + 1 ) );
SET_SP( GET_SP() + 3 );
goto set_psw;
case 0x8E: // POP PSW
POP( temp );
set_psw:
SET_PSW( temp );
goto loop;
}
case 0x0D: { // PUSH PSW
int temp;
GET_PSW( temp );
PUSH( temp );
goto loop;
}
case 0x2D: // PUSH A
PUSH( a );
goto loop;
case 0x4D: // PUSH X
PUSH( x );
goto loop;
case 0x6D: // PUSH Y
PUSH( y );
goto loop;
case 0xAE: // POP A
POP( a );
goto loop;
case 0xCE: // POP X
POP( x );
goto loop;
case 0xEE: // POP Y
POP( y );
goto loop;
// 15. BIT OPERATION COMMANDS
case 0x02: // SET1
case 0x22:
case 0x42:
case 0x62:
case 0x82:
case 0xA2:
case 0xC2:
case 0xE2:
case 0x12: // CLR1
case 0x32:
case 0x52:
case 0x72:
case 0x92:
case 0xB2:
case 0xD2:
case 0xF2: {
int bit = 1 << (opcode >> 5);
int mask = ~bit;
if ( opcode & 0x10 )
bit = 0;
data += dp;
WRITE( 0, data, (READ( -1, data ) & mask) | bit );
goto inc_pc_loop;
}
case 0x0E: // TSET1 abs
case 0x4E: // TCLR1 abs
data = READ_PC16( pc );
pc += 2;
{
unsigned temp = READ( -2, data );
nz = (uint8_t) (a - temp);
temp &= ~a;
if ( opcode == 0x0E )
temp |= a;
WRITE( 0, data, temp );
}
goto loop;
case 0x4A: // AND1 C,mem.bit
c &= MEM_BIT( 0 );
pc += 2;
goto loop;
case 0x6A: // AND1 C,/mem.bit
c &= ~MEM_BIT( 0 );
pc += 2;
goto loop;
case 0x0A: // OR1 C,mem.bit
c |= MEM_BIT( -1 );
pc += 2;
goto loop;
case 0x2A: // OR1 C,/mem.bit
c |= ~MEM_BIT( -1 );
pc += 2;
goto loop;
case 0x8A: // EOR1 C,mem.bit
c ^= MEM_BIT( -1 );
pc += 2;
goto loop;
case 0xEA: // NOT1 mem.bit
data = READ_PC16( pc );
pc += 2;
{
unsigned temp = READ( -1, data & 0x1FFF );
temp ^= 1 << (data >> 13);
WRITE( 0, data & 0x1FFF, temp );
}
goto loop;
case 0xCA: // MOV1 mem.bit,C
data = READ_PC16( pc );
pc += 2;
{
unsigned temp = READ( -2, data & 0x1FFF );
unsigned bit = data >> 13;
temp = (temp & ~(1 << bit)) | ((c >> 8 & 1) << bit);
WRITE( 0, data & 0x1FFF, temp + no_read_before_write );
}
goto loop;
case 0xAA: // MOV1 C,mem.bit
c = MEM_BIT( 0 );
pc += 2;
goto loop;
// 16. PROGRAM PSW FLAG OPERATION COMMANDS
case 0x60: // CLRC
c = 0;
goto loop;
case 0x80: // SETC
c = ~0;
goto loop;
case 0xED: // NOTC
c ^= 0x100;
goto loop;
case 0xE0: // CLRV
psw &= ~(v40 | h08);
goto loop;
case 0x20: // CLRP
dp = 0;
goto loop;
case 0x40: // SETP
dp = 0x100;
goto loop;
case 0xA0: // EI
SUSPICIOUS_OPCODE( "EI" );
psw |= i04;
goto loop;
case 0xC0: // DI
SUSPICIOUS_OPCODE( "DI" );
psw &= ~i04;
goto loop;
// 17. OTHER COMMANDS
case 0x00: // NOP
goto loop;
case 0xFF:{// STOP
// handle PC wrap-around
unsigned addr = GET_PC() - 1;
if ( addr >= 0x10000 )
{
addr &= 0xFFFF;
SET_PC( addr );
debug_printf( "SPC: PC wrapped around\n" );
goto loop;
}
}
// fall through
case 0xEF: // SLEEP
SUSPICIOUS_OPCODE( "STOP/SLEEP" );
--pc;
rel_time = 0;
m.cpu_error = "SPC emulation error";
goto stop;
} // switch
assert( 0 ); // catch any unhandled instructions
}
out_of_time:
rel_time -= m.cycle_table [*pc]; // undo partial execution of opcode
stop:
// Uncache registers
if ( GET_PC() >= 0x10000 )
debug_printf( "SPC: PC wrapped around\n" );
m.cpu_regs.pc = (uint16_t) GET_PC();
m.cpu_regs.sp = ( uint8_t) GET_SP();
m.cpu_regs.a = ( uint8_t) a;
m.cpu_regs.x = ( uint8_t) x;
m.cpu_regs.y = ( uint8_t) y;
{
int temp;
GET_PSW( temp );
m.cpu_regs.psw = (uint8_t) temp;
}
}
SPC_CPU_RUN_FUNC_END