gbemu/lib/cpu_proc.c

50 lines
928 B
C

#include <cpu.h>
#include <emu.h>
//process CPU instructions...
static void proc_none(cpu_context *ctx) {
printf("INVALID INSTRUCTION!\n");
exit(-7);
}
static void proc_nop(cpu_context *ctx) {
}
static void proc_ld(cpu_context *ctx) {
//TODO
}
static bool check_condition(cpu_context *ctx) {
bool z = CPU_FLAG_Z;
bool c = CPU_FLAG_C;
switch(ctx->cur_inst->cond) {
case CT_NONE: return true;
case CT_C: return c;
case CT_NC: return !c;
case CT_Z: return z;
case CT_NZ: return !z;
}
return false;
}
static void proc_jp(cpu_context *ctx) {
if (check_condition(ctx)) {
ctx->regs.pc = ctx->fetched_data;
emu_cycles(1);
}
}
IN_PROC processors[] = {
[IN_NONE] = proc_none,
[IN_NOP] = proc_nop,
[IN_LD] = proc_ld,
[IN_JP] = proc_jp,
};
IN_PROC inst_get_processor(in_type type) {
return processors[type];
}