uint16_t label_lookup_write(
label_table_t * from, label_table_t * to,
char * label, uint16_t address
)
{
uint16_t found_address;
if ((found_address = label_lookup(from, label)))
return found_address;
label_write(to, label, address);
return 0;
}
static int cbranch_op(struct code_rom *rom, uint8_t invert,
uint8_t zero, const char *label)
{
struct label *l;
uint16_t insn;
invert = !!invert;
zero = !!zero;
l = label_lookup(rom, label);
if ( NULL == l ) {
fprintf(stderr, "%s:%u: label not found: %s\n",
rom->fn, rom->line, label);
return 0;
}
insn = (1 << 8) | (invert << 7) | (zero << 6) | l->addr;
return emit_insn(rom, insn);
}
static int add_label(struct code_rom *rom, char *ptr)
{
struct label *l;
if ( !label_is_valid(ptr) ) {
fprintf(stderr, "%s:%u: invalid label name: %s\n",
rom->fn, rom->line, ptr);
return 0;
}
if ( label_lookup(rom, ptr) ) {
fprintf(stderr, "%s:%u: duplicate label: %s\n",
rom->fn, rom->line, ptr);
return 0;
}
l = calloc(1, sizeof(*l));
if ( NULL == l ) {
fprintf(stderr, "%s:%u: %s\n",
rom->fn, rom->line, strerror(errno));
return 0;
}
l->name = strdup(ptr);
if ( NULL == l->name ) {
fprintf(stderr, "%s:%u: %s\n",
rom->fn, rom->line, strerror(errno));
free(l);
return 0;
}
l->addr = rom->addr;
l->next = rom->labels;
rom->labels = l;
return 1;
}
