/* Can it possibly exist in the cache? */
if (LIKELY (old_obj->read_count + old_obj->write_count))
{
- /* As reported by Herman ten Brugge, we need to scan the entire
- cache for entries that may hit this object. */
uintptr_t low = old_obj->low;
uintptr_t high = old_obj->high;
- struct __mf_cache *entry = & __mf_lookup_cache [0];
+ struct __mf_cache *entry;
unsigned i;
- for (i = 0; i <= __mf_lc_mask; i++, entry++)
- {
- /* NB: the "||" in the following test permits this code to
- tolerate the situation introduced by __mf_check over
- contiguous objects, where a cache entry spans several
- objects. */
- if (entry->low == low || entry->high == high)
+ if ((high - low) >= (__mf_lc_mask << __mf_lc_shift))
+ {
+ /* For large objects (>= cache size - 1) check the whole cache. */
+ entry = & __mf_lookup_cache [0];
+ for (i = 0; i <= __mf_lc_mask; i++, entry++)
{
- entry->low = MAXPTR;
- entry->high = MINPTR;
+ /* NB: the "||" in the following test permits this code to
+ tolerate the situation introduced by __mf_check over
+ contiguous objects, where a cache entry spans several
+ objects. */
+ if (entry->low == low || entry->high == high)
+ {
+ entry->low = MAXPTR;
+ entry->high = MINPTR;
+ }
}
}
+ else
+ {
+ /* Object is now smaller then cache size. */
+ unsigned entry_low_idx = __MF_CACHE_INDEX (low);
+ unsigned entry_high_idx = __MF_CACHE_INDEX (high);
+ if (entry_low_idx <= entry_high_idx)
+ {
+ entry = & __mf_lookup_cache [entry_low_idx];
+ for (i = entry_low_idx; i <= entry_high_idx; i++, entry++)
+ {
+ /* NB: the "||" in the following test permits this code to
+ tolerate the situation introduced by __mf_check over
+ contiguous objects, where a cache entry spans several
+ objects. */
+ if (entry->low == low || entry->high == high)
+ {
+ entry->low = MAXPTR;
+ entry->high = MINPTR;
+ }
+ }
+ }
+ else
+ {
+ /* Object wrapped around the end of the cache. First search
+ from low to end of cache and then from 0 to high. */
+ entry = & __mf_lookup_cache [entry_low_idx];
+ for (i = entry_low_idx; i <= __mf_lc_mask; i++, entry++)
+ {
+ /* NB: the "||" in the following test permits this code to
+ tolerate the situation introduced by __mf_check over
+ contiguous objects, where a cache entry spans several
+ objects. */
+ if (entry->low == low || entry->high == high)
+ {
+ entry->low = MAXPTR;
+ entry->high = MINPTR;
+ }
+ }
+ entry = & __mf_lookup_cache [0];
+ for (i = 0; i <= entry_high_idx; i++, entry++)
+ {
+ /* NB: the "||" in the following test permits this code to
+ tolerate the situation introduced by __mf_check over
+ contiguous objects, where a cache entry spans several
+ objects. */
+ if (entry->low == low || entry->high == high)
+ {
+ entry->low = MAXPTR;
+ entry->high = MINPTR;
+ }
+ }
+ }
+ }
}
}