drc_core *drc_init(UINT8 cpunum, drc_config *config)
{
int address_bits = config->address_bits;
int effective_address_bits = address_bits - config->lsbs_to_ignore;
drc_core *drc;
/* allocate memory */
drc = malloc(sizeof(*drc));
if (!drc)
return NULL;
memset(drc, 0, sizeof(*drc));
/* copy in relevant data from the config */
drc->pcptr = config->pcptr;
drc->icountptr = config->icountptr;
drc->esiptr = config->esiptr;
drc->cb_reset = config->cb_reset;
drc->cb_recompile = config->cb_recompile;
drc->cb_entrygen = config->cb_entrygen;
drc->uses_fp = config->uses_fp;
drc->uses_sse = config->uses_sse;
drc->pc_in_memory = config->pc_in_memory;
drc->icount_in_memory = config->icount_in_memory;
drc->fpcw_curr = fp_control[0];
drc->mxcsr_curr = sse_control[0];
/* allocate cache */
drc->cache_base = osd_alloc_executable(config->cache_size);
if (!drc->cache_base)
return NULL;
drc->cache_end = drc->cache_base + config->cache_size;
drc->cache_danger = drc->cache_end - 65536;
/* compute shifts and masks */
drc->l1bits = effective_address_bits/2;
drc->l2bits = effective_address_bits - drc->l1bits;
drc->l1shift = config->lsbs_to_ignore + drc->l2bits;
drc->l2mask = ((1 << drc->l2bits) - 1) << config->lsbs_to_ignore;
drc->l2scale = 4 >> config->lsbs_to_ignore;
/* allocate lookup tables */
drc->lookup_l1 = malloc(sizeof(*drc->lookup_l1) * (1 << drc->l1bits));
drc->lookup_l2_recompile = malloc(sizeof(*drc->lookup_l2_recompile) * (1 << drc->l2bits));
if (!drc->lookup_l1 || !drc->lookup_l2_recompile)
return NULL;
memset(drc->lookup_l1, 0, sizeof(*drc->lookup_l1) * (1 << drc->l1bits));
memset(drc->lookup_l2_recompile, 0, sizeof(*drc->lookup_l2_recompile) * (1 << drc->l2bits));
/* allocate the sequence and tentative lists */
drc->sequence_count_max = config->max_instructions;
drc->sequence_list = malloc(drc->sequence_count_max * sizeof(*drc->sequence_list));
drc->tentative_count_max = config->max_instructions;
drc->tentative_list = malloc(drc->tentative_count_max * sizeof(*drc->tentative_list));
if (!drc->sequence_list || !drc->tentative_list)
return NULL;
/* seed the cache */
drc_cache_reset(drc);
return drc;
}
void *drc_alloc(drc_core *drc, size_t amount)
{
/* if we don't have enough space, reset the cache */
if (drc->cache_top >= drc->cache_danger - amount)
drc_cache_reset(drc);
/* if we still don't have enough space, fail */
if (drc->cache_top >= drc->cache_danger - amount)
return NULL;
/* adjust the end and danger values downward */
drc->cache_end -= amount;
drc->cache_danger -= amount;
return drc->cache_end;
}