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| author | Peter Fors <peter.fors@mindkiller.com> | 2025-03-29 19:57:00 +0100 |
|---|---|---|
| committer | Peter Fors <peter.fors@mindkiller.com> | 2025-03-29 19:57:00 +0100 |
| commit | e8ff6bf2ab9982c5e5ab8d8f4e7adcc5207d079d (patch) | |
| tree | a91ec214f5cd0e95c3d26ee0ba916cb187e3aede /cpu_opcodes_ud.c | |
first mknes commit
Diffstat (limited to 'cpu_opcodes_ud.c')
| -rw-r--r-- | cpu_opcodes_ud.c | 1232 |
1 files changed, 1232 insertions, 0 deletions
diff --git a/cpu_opcodes_ud.c b/cpu_opcodes_ud.c new file mode 100644 index 0000000..a679cae --- /dev/null +++ b/cpu_opcodes_ud.c @@ -0,0 +1,1232 @@ + + + +// NOP + +static void opcode_nop_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + memory_read(state, cpu->pc++); // T1: consume operand +} + +static void opcode_nop_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); // T1 + memory_read_dummy(state, addr); // T2 +} + +static void opcode_nop_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); // T1 + uint8_t hi = memory_read(state, cpu->pc++); // T2 + uint16_t addr = lo | (hi << 8); + + memory_read_dummy(state, addr); // T3 +} + +static void opcode_nop_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); // T1: fetch operand + memory_read_dummy(state, base); // T2: internal timing quirk (not used, but real) + uint8_t addr = (base + cpu->x) & 0xff; + memory_read_dummy(state, addr); // T3: final bus read to correct address +} + +static void opcode_nop_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); // T1 + uint8_t hi = memory_read(state, cpu->pc++); // T2 + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); // T3 dummy read + } + + memory_read_dummy(state, addr); // T4 — final bus cycle (even if not used) +} + + +static void opcode_nop_implied(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + memory_read_dummy(state, cpu->pc); // T1 +} + + +// LAX + +static void opcode_lax_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t value = memory_read(state, cpu->pc++); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_zpy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->y) & 0xff; + + uint8_t value = memory_read(state, addr); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + +static void opcode_lax_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + cpu->a = value; + cpu->x = value; + update_zn(cpu, value); +} + + +// SAX + +static void opcode_sax_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); // T1 + memory_read_dummy(state, zp); // T2 + uint8_t ptr = zp + cpu->x; + uint8_t lo = memory_read(state, ptr & 0xff); // T3 + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); // T4 + uint16_t addr = lo | (hi << 8); + memory_write(state, addr, cpu->a & cpu->x); // T5 +} + + +static void opcode_sax_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + memory_write(state, addr, cpu->a & cpu->x); +} + +static void opcode_sax_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + memory_write(state, addr, cpu->a & cpu->x); +} + +static void opcode_sax_zpy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->y) & 0xff; + + memory_write(state, addr, cpu->a & cpu->x); +} + +static void opcode_sax_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + memory_write(state, addr, cpu->a & cpu->x); +} + +static void opcode_sax_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); // T1 + uint8_t lo = memory_read(state, zp); // T2 + uint8_t hi = memory_read(state, (zp + 1) & 0xff); // T3 + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); // T4 (always) + memory_write(state, addr, cpu->a & cpu->x); // T5 +} + + + +// DCP + +static void opcode_dcp_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + +static void opcode_dcp_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value--; + memory_write(state, addr, value); + + uint16_t tmp = cpu->a - value; + cpu->c = (cpu->a >= value); + update_zn(cpu, tmp & 0xff); +} + + +// ISC + +static void opcode_isc_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + +static void opcode_isc_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + value++; + memory_write(state, addr, value); + + sbc(cpu, value); +} + + +// SLO + +static void opcode_slo_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + +static void opcode_slo_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = (value >> 7) & 1; + value <<= 1; + + memory_write(state, addr, value); + cpu->a |= value; + update_zn(cpu, cpu->a); +} + + +// RLA + +static void opcode_rla_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + +static void opcode_rla_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t in = cpu->c; + cpu->c = (value >> 7) & 1; + value = (value << 1) | in; + + memory_write(state, addr, value); + cpu->a &= value; + update_zn(cpu, cpu->a); +} + + +// SRE + +static void opcode_sre_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + +static void opcode_sre_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + cpu->c = value & 1; + value >>= 1; + + memory_write(state, addr, value); + cpu->a ^= value; + update_zn(cpu, cpu->a); +} + + +// opcode_rra + +static void opcode_rra_indx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + memory_read_dummy(state, zp); + + uint8_t ptr = (zp + cpu->x) & 0xff; + uint8_t lo = memory_read(state, ptr); + uint8_t hi = memory_read(state, (ptr + 1) & 0xff); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_zp(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t addr = memory_read(state, cpu->pc++); + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_abs(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t addr = lo | (hi << 8); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_indy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t zp = memory_read(state, cpu->pc++); + uint8_t lo = memory_read(state, zp); + uint8_t hi = memory_read(state, (zp + 1) & 0xff); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + if((base & 0xff00) != (addr & 0xff00)) { + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + } + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_zpx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t base = memory_read(state, cpu->pc++); + memory_read_dummy(state, base); + uint8_t addr = (base + cpu->x) & 0xff; + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_absy(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->y; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + +static void opcode_rra_absx(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t lo = memory_read(state, cpu->pc++); + uint8_t hi = memory_read(state, cpu->pc++); + uint16_t base = lo | (hi << 8); + uint16_t addr = base + cpu->x; + + memory_read_dummy(state, (base & 0xff00) | (addr & 0x00ff)); + + uint8_t value = memory_read(state, addr); + memory_write(state, addr, value); // dummy write + + uint8_t new_c = value & 1; + value = (value >> 1) | (cpu->c << 7); + cpu->c = new_c; + + memory_write(state, addr, value); + adc(cpu, value); +} + + +// ALR + +static void opcode_alr_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + uint8_t value = memory_read(state, cpu->pc++); + cpu->a &= value; + cpu->c = cpu->a & 1; + cpu->a >>= 1; + update_zn(cpu, cpu->a); +} + + +// ANC + +static void opcode_anc_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + uint8_t value = memory_read(state, cpu->pc++); + cpu->a &= value; + cpu->c = (cpu->a >> 7) & 1; + update_zn(cpu, cpu->a); +} + + +// ARR + +static void opcode_arr_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t value = memory_read(state, cpu->pc++); + cpu->a &= value; + + uint8_t in = cpu->c << 7; + cpu->c = (cpu->a >> 0) & 1; + cpu->a = (cpu->a >> 1) | in; + + update_zn(cpu, cpu->a); + cpu->v = ((cpu->a >> 6) ^ (cpu->a >> 5)) & 1; +} + + +// XAA + +static void opcode_xaa_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t value = memory_read(state, cpu->pc++); + cpu->a = cpu->a & cpu->x & value; + update_zn(cpu, cpu->a); +} + + +// AXS + +static void opcode_axs_imm(struct nes_state * restrict state) { + struct cpu_state * restrict cpu = &state->cpu; + + uint8_t value = memory_read(state, cpu->pc++); + cpu->a = cpu->x & value; + update_zn(cpu, cpu->a); +} + + + + +__attribute__((noinline)) +static void init_opcode_ud_lut(void) { + opcode_lut[0x80] = opcode_nop_imm; + opcode_lut[0x82] = opcode_nop_imm; + opcode_lut[0x89] = opcode_nop_imm; + opcode_lut[0xc2] = opcode_nop_imm; + opcode_lut[0xe2] = opcode_nop_imm; + + opcode_lut[0x04] = opcode_nop_zp; + opcode_lut[0x44] = opcode_nop_zp; + opcode_lut[0x64] = opcode_nop_zp; + + opcode_lut[0x0c] = opcode_nop_abs; + + opcode_lut[0x14] = opcode_nop_zpx; + opcode_lut[0x34] = opcode_nop_zpx; + opcode_lut[0x54] = opcode_nop_zpx; + opcode_lut[0x74] = opcode_nop_zpx; + opcode_lut[0xd4] = opcode_nop_zpx; + opcode_lut[0xf4] = opcode_nop_zpx; + + opcode_lut[0x1c] = opcode_nop_absx; + opcode_lut[0x3c] = opcode_nop_absx; + opcode_lut[0x5c] = opcode_nop_absx; + opcode_lut[0x7c] = opcode_nop_absx; + opcode_lut[0xdc] = opcode_nop_absx; + opcode_lut[0xfc] = opcode_nop_absx; + + opcode_lut[0x1a] = opcode_nop_implied; + opcode_lut[0x3a] = opcode_nop_implied; + opcode_lut[0x5a] = opcode_nop_implied; + opcode_lut[0x7a] = opcode_nop_implied; + opcode_lut[0xda] = opcode_nop_implied; + opcode_lut[0xfa] = opcode_nop_implied; + + opcode_lut[0xab] = opcode_lax_imm; + opcode_lut[0xa3] = opcode_lax_indx; + opcode_lut[0xaf] = opcode_lax_abs; + opcode_lut[0xbb] = opcode_lax_absy; + opcode_lut[0xbf] = opcode_lax_absy; + opcode_lut[0xa7] = opcode_lax_zp; + opcode_lut[0xb7] = opcode_lax_zpy; + opcode_lut[0xb3] = opcode_lax_indy; + + opcode_lut[0x83] = opcode_sax_indx; + opcode_lut[0x8f] = opcode_sax_abs; + opcode_lut[0x9f] = opcode_sax_absy; + opcode_lut[0x87] = opcode_sax_zp; + opcode_lut[0x97] = opcode_sax_zpy; + opcode_lut[0x93] = opcode_sax_indy; + + opcode_lut[0xc3] = opcode_dcp_indx; + opcode_lut[0xc7] = opcode_dcp_zp; + opcode_lut[0xcf] = opcode_dcp_abs; + opcode_lut[0xd3] = opcode_dcp_indy; + opcode_lut[0xd7] = opcode_dcp_zpx; + opcode_lut[0xdb] = opcode_dcp_absy; + opcode_lut[0xdf] = opcode_dcp_absx; + + opcode_lut[0xe3] = opcode_isc_indx; + opcode_lut[0xe7] = opcode_isc_zp; + opcode_lut[0xef] = opcode_isc_abs; + opcode_lut[0xf3] = opcode_isc_indy; + opcode_lut[0xf7] = opcode_isc_zpx; + opcode_lut[0xfb] = opcode_isc_absy; + opcode_lut[0xff] = opcode_isc_absx; + + opcode_lut[0x03] = opcode_slo_indx; + opcode_lut[0x07] = opcode_slo_zp; + opcode_lut[0x0f] = opcode_slo_abs; + opcode_lut[0x13] = opcode_slo_indy; + opcode_lut[0x17] = opcode_slo_zpx; + opcode_lut[0x1b] = opcode_slo_absy; + opcode_lut[0x1f] = opcode_slo_absx; + + opcode_lut[0x23] = opcode_rla_indx; + opcode_lut[0x27] = opcode_rla_zp; + opcode_lut[0x2f] = opcode_rla_abs; + opcode_lut[0x33] = opcode_rla_indy; + opcode_lut[0x37] = opcode_rla_zpx; + opcode_lut[0x3b] = opcode_rla_absy; + opcode_lut[0x3f] = opcode_rla_absx; + + opcode_lut[0x43] = opcode_sre_indx; + opcode_lut[0x47] = opcode_sre_zp; + opcode_lut[0x4f] = opcode_sre_abs; + opcode_lut[0x53] = opcode_sre_indy; + opcode_lut[0x57] = opcode_sre_zpx; + opcode_lut[0x5b] = opcode_sre_absy; + opcode_lut[0x5f] = opcode_sre_absx; + + opcode_lut[0x63] = opcode_rra_indx; + opcode_lut[0x67] = opcode_rra_zp; + opcode_lut[0x6f] = opcode_rra_abs; + opcode_lut[0x73] = opcode_rra_indy; + opcode_lut[0x77] = opcode_rra_zpx; + opcode_lut[0x7b] = opcode_rra_absy; + opcode_lut[0x7f] = opcode_rra_absx; + + opcode_lut[0x32] = opcode_anc_imm; + opcode_lut[0x4b] = opcode_alr_imm; + opcode_lut[0x8b] = opcode_xaa_imm; + opcode_lut[0xcb] = opcode_axs_imm; + opcode_lut[0x6b] = opcode_arr_imm; +} |
