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[emulate] eliminate jumpaddr global variable

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This commit is contained in:
Gwenhael Le Moine 2024-06-11 12:14:23 +02:00
parent 964f34a92a
commit 875a94ff14
No known key found for this signature in database
GPG key ID: FDFE3669426707A7
1 changed files with 66 additions and 102 deletions
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168
src/emu_emulate.c
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@ -48,8 +48,6 @@ int conf_bank2 = 0x00000;
short conf_tab[] = { 1, 2, 2, 2, 2, 0 }; short conf_tab[] = { 1, 2, 2, 2, 2, 0 };
static long jumpaddr;
unsigned long instructions = 0; unsigned long instructions = 0;
unsigned long old_instr = 0; unsigned long old_instr = 0;
@ -555,7 +553,7 @@ void load_addr( word_20* dat, long addr, int n )
} }
} }
int decode_group_80( void ) static inline int _step_instruction_group_80( void )
{ {
int t, op3, op4, op5, op6; int t, op3, op4, op5, op6;
unsigned char* REG; unsigned char* REG;
@ -657,27 +655,23 @@ int decode_group_80( void )
if ( op6 ) { if ( op6 ) {
if ( op6 & 0x80 ) if ( op6 & 0x80 )
op6 |= jumpmasks[ 2 ]; op6 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op6 ) & 0xfffff; saturn.PC = ( saturn.PC + op6 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
}
} else { } else
saturn.PC += 7; saturn.PC += 7;
}
return 0; return 0;
case 0xc: /* PC=(A) */ case 0xc: /* PC=(A) */
addr = dat_to_addr( saturn.A ); addr = dat_to_addr( saturn.A );
jumpaddr = read_nibbles( addr, 5 ); saturn.PC = read_nibbles( addr, 5 );
saturn.PC = jumpaddr;
return 0; return 0;
case 0xd: /* BUSCD */ case 0xd: /* BUSCD */
saturn.PC += 4; saturn.PC += 4;
return 0; return 0;
case 0xe: /* PC=(C) */ case 0xe: /* PC=(C) */
addr = dat_to_addr( saturn.C ); addr = dat_to_addr( saturn.C );
jumpaddr = read_nibbles( addr, 5 ); saturn.PC = read_nibbles( addr, 5 );
saturn.PC = jumpaddr;
return 0; return 0;
case 0xf: /* INTOFF */ case 0xf: /* INTOFF */
saturn.PC += 4; saturn.PC += 4;
@ -724,7 +718,7 @@ int decode_group_80( void )
} }
} }
int decode_group_1( void ) static inline int _step_instruction_group_1( void )
{ {
int op, op2, op3, op4; int op, op2, op3, op4;
@ -1122,7 +1116,7 @@ int decode_group_1( void )
} }
} }
static inline int decode_8_thru_f( int op1 ) static inline int _step_instruction_group_8_thru_f( int op1 )
{ {
int op2, op3, op4, op5, op6; int op2, op3, op4, op5, op6;
@ -1131,7 +1125,7 @@ static inline int decode_8_thru_f( int op1 )
case 8: case 8:
switch ( op2 ) { switch ( op2 ) {
case 0: case 0:
return decode_group_80(); return _step_instruction_group_80();
case 1: case 1:
op3 = read_nibble( saturn.PC + 2 ); op3 = read_nibble( saturn.PC + 2 );
switch ( op3 ) { switch ( op3 ) {
@ -1402,12 +1396,10 @@ static inline int decode_8_thru_f( int op1 )
op4 = read_nibble( saturn.PC + 3 ); op4 = read_nibble( saturn.PC + 3 );
switch ( op4 ) { switch ( op4 ) {
case 2: /* PC=A */ case 2: /* PC=A */
jumpaddr = dat_to_addr( saturn.A ); saturn.PC = dat_to_addr( saturn.A );
saturn.PC = jumpaddr;
return 0; return 0;
case 3: /* PC=C */ case 3: /* PC=C */
jumpaddr = dat_to_addr( saturn.C ); saturn.PC = dat_to_addr( saturn.C );
saturn.PC = jumpaddr;
return 0; return 0;
case 4: /* A=PC */ case 4: /* A=PC */
saturn.PC += 4; saturn.PC += 4;
@ -1419,15 +1411,13 @@ static inline int decode_8_thru_f( int op1 )
return 0; return 0;
case 6: /* APCEX */ case 6: /* APCEX */
saturn.PC += 4; saturn.PC += 4;
jumpaddr = dat_to_addr( saturn.A );
addr_to_dat( saturn.PC, saturn.A ); addr_to_dat( saturn.PC, saturn.A );
saturn.PC = jumpaddr; saturn.PC = dat_to_addr( saturn.A );
return 0; return 0;
case 7: /* CPCEX */ case 7: /* CPCEX */
saturn.PC += 4; saturn.PC += 4;
jumpaddr = dat_to_addr( saturn.C );
addr_to_dat( saturn.PC, saturn.C ); addr_to_dat( saturn.PC, saturn.C );
saturn.PC = jumpaddr; saturn.PC = dat_to_addr( saturn.C );
return 0; return 0;
default: default:
return 1; return 1;
@ -1465,14 +1455,12 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
}
} else { } else
saturn.PC += 5; saturn.PC += 5;
}
return 0; return 0;
case 4: case 4:
case 5: case 5:
@ -1498,14 +1486,11 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} } else
} else {
saturn.PC += 5; saturn.PC += 5;
}
return 0; return 0;
case 8: case 8:
case 9: case 9:
@ -1520,14 +1505,11 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} } else
} else {
saturn.PC += 5; saturn.PC += 5;
}
return 0; return 0;
case 0xa: case 0xa:
op3 = read_nibble( saturn.PC + 2 ); op3 = read_nibble( saturn.PC + 2 );
@ -1589,14 +1571,11 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} } else
} else {
saturn.PC += 5; saturn.PC += 5;
}
return 0; return 0;
case 0xb: case 0xb:
op3 = read_nibble( saturn.PC + 2 ); op3 = read_nibble( saturn.PC + 2 );
@ -1658,40 +1637,33 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} } else
} else {
saturn.PC += 5; saturn.PC += 5;
}
return 0; return 0;
case 0xc: case 0xc:
op3 = read_nibbles( saturn.PC + 2, 4 ); op3 = read_nibbles( saturn.PC + 2, 4 );
if ( op3 & 0x8000 ) if ( op3 & 0x8000 )
op3 |= jumpmasks[ 4 ]; op3 |= jumpmasks[ 4 ];
jumpaddr = ( saturn.PC + op3 + 2 ) & 0xfffff; saturn.PC = ( saturn.PC + op3 + 2 ) & 0xfffff;
saturn.PC = jumpaddr;
return 0; return 0;
case 0xd: case 0xd:
op3 = read_nibbles( saturn.PC + 2, 5 ); op3 = read_nibbles( saturn.PC + 2, 5 );
jumpaddr = op3; saturn.PC = op3;
saturn.PC = jumpaddr;
return 0; return 0;
case 0xe: case 0xe:
op3 = read_nibbles( saturn.PC + 2, 4 ); op3 = read_nibbles( saturn.PC + 2, 4 );
if ( op3 & 0x8000 ) if ( op3 & 0x8000 )
op3 |= jumpmasks[ 4 ]; op3 |= jumpmasks[ 4 ];
jumpaddr = ( saturn.PC + op3 + 6 ) & 0xfffff;
push_return_addr( saturn.PC + 6 ); push_return_addr( saturn.PC + 6 );
saturn.PC = jumpaddr; saturn.PC = ( saturn.PC + op3 + 6 ) & 0xfffff;
return 0; return 0;
case 0xf: case 0xf:
op3 = read_nibbles( saturn.PC + 2, 5 ); op3 = read_nibbles( saturn.PC + 2, 5 );
jumpaddr = op3;
push_return_addr( saturn.PC + 7 ); push_return_addr( saturn.PC + 7 );
saturn.PC = jumpaddr; saturn.PC = op3;
return 0; return 0;
default: default:
return 1; return 1;
@ -1812,8 +1784,7 @@ static inline int decode_8_thru_f( int op1 )
if ( op4 ) { if ( op4 ) {
if ( op4 & 0x80 ) if ( op4 & 0x80 )
op4 |= jumpmasks[ 2 ]; op4 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op4 ) & 0xfffff; saturn.PC = ( saturn.PC + op4 ) & 0xfffff;
saturn.PC = jumpaddr;
} else { } else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} }
@ -2391,8 +2362,6 @@ int step_instruction( void )
int op0, op1, op2, op3; int op0, op1, op2, op3;
int stop = 0; int stop = 0;
jumpaddr = 0;
op0 = read_nibble( saturn.PC ); op0 = read_nibble( saturn.PC );
switch ( op0 ) { switch ( op0 ) {
case 0: case 0:
@ -2422,14 +2391,12 @@ int step_instruction( void )
saturn.hexmode = DEC; saturn.hexmode = DEC;
break; break;
case 6: /* RSTK=C */ case 6: /* RSTK=C */
jumpaddr = dat_to_addr( saturn.C ); push_return_addr( dat_to_addr( saturn.C ) );
push_return_addr( jumpaddr );
saturn.PC += 2; saturn.PC += 2;
break; break;
case 7: /* C=RSTK */ case 7: /* C=RSTK */
saturn.PC += 2; saturn.PC += 2;
jumpaddr = pop_return_addr(); addr_to_dat( pop_return_addr(), saturn.C );
addr_to_dat( jumpaddr, saturn.C );
break; break;
case 8: /* CLRST */ case 8: /* CLRST */
saturn.PC += 2; saturn.PC += 2;
@ -2549,7 +2516,7 @@ int step_instruction( void )
} }
break; break;
case 1: case 1:
stop = decode_group_1(); stop = _step_instruction_group_1();
break; break;
case 2: case 2:
op2 = read_nibble( saturn.PC + 1 ); op2 = read_nibble( saturn.PC + 1 );
@ -2565,17 +2532,17 @@ int step_instruction( void )
op2 = read_nibbles( saturn.PC + 1, 2 ); op2 = read_nibbles( saturn.PC + 1, 2 );
if ( op2 == 0x02 ) { if ( op2 == 0x02 ) {
saturn.PC += 3; saturn.PC += 3;
} else if ( saturn.CARRY != 0 ) {
if ( op2 ) {
if ( op2 & 0x80 )
op2 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op2 + 1 ) & 0xfffff;
saturn.PC = jumpaddr;
} else {
saturn.PC = pop_return_addr();
}
} else { } else {
saturn.PC += 3; if ( saturn.CARRY != 0 ) {
if ( op2 ) {
if ( op2 & 0x80 )
op2 |= jumpmasks[ 2 ];
saturn.PC = ( saturn.PC + op2 + 1 ) & 0xfffff;
} else
saturn.PC = pop_return_addr();
} else
saturn.PC += 3;
} }
break; break;
case 5: case 5:
@ -2584,43 +2551,40 @@ int step_instruction( void )
if ( op2 ) { if ( op2 ) {
if ( op2 & 0x80 ) if ( op2 & 0x80 )
op2 |= jumpmasks[ 2 ]; op2 |= jumpmasks[ 2 ];
jumpaddr = ( saturn.PC + op2 + 1 ) & 0xfffff; saturn.PC = ( saturn.PC + op2 + 1 ) & 0xfffff;
saturn.PC = jumpaddr; } else
} else {
saturn.PC = pop_return_addr(); saturn.PC = pop_return_addr();
} } else
} else {
saturn.PC += 3; saturn.PC += 3;
}
break; break;
case 6: case 6:
op2 = read_nibbles( saturn.PC + 1, 3 ); op2 = read_nibbles( saturn.PC + 1, 3 );
if ( op2 == 0x003 ) { if ( op2 == 0x003 )
saturn.PC += 4; saturn.PC += 4;
} else if ( op2 == 0x004 ) { else {
op3 = read_nibbles( saturn.PC + 4, 1 ); if ( op2 == 0x004 ) {
saturn.PC += 5; op3 = read_nibbles( saturn.PC + 4, 1 );
if ( op3 != 0 ) { saturn.PC += 5;
enter_debugger |= TRAP_INSTRUCTION; if ( op3 != 0 ) {
return 1; enter_debugger |= TRAP_INSTRUCTION;
return 1;
}
} else {
if ( op2 & 0x800 )
op2 |= jumpmasks[ 3 ];
saturn.PC = ( op2 + saturn.PC + 1 ) & 0xfffff;
} }
} else {
if ( op2 & 0x800 )
op2 |= jumpmasks[ 3 ];
jumpaddr = ( op2 + saturn.PC + 1 ) & 0xfffff;
saturn.PC = jumpaddr;
} }
break; break;
case 7: case 7:
op2 = read_nibbles( saturn.PC + 1, 3 ); op2 = read_nibbles( saturn.PC + 1, 3 );
if ( op2 & 0x800 ) if ( op2 & 0x800 )
op2 |= jumpmasks[ 3 ]; op2 |= jumpmasks[ 3 ];
jumpaddr = ( op2 + saturn.PC + 4 ) & 0xfffff;
push_return_addr( saturn.PC + 4 ); push_return_addr( saturn.PC + 4 );
saturn.PC = jumpaddr; saturn.PC = ( op2 + saturn.PC + 4 ) & 0xfffff;
break; break;
default: default:
stop = decode_8_thru_f( op0 ); stop = _step_instruction_group_8_thru_f( op0 );
break; break;
} }
instructions++; instructions++;