diff options
Diffstat (limited to 'libmudflap/mf-runtime.c')
| -rw-r--r-- | libmudflap/mf-runtime.c | 80 |
1 files changed, 68 insertions, 12 deletions
diff --git a/libmudflap/mf-runtime.c b/libmudflap/mf-runtime.c index d6e32262e06..8501cca6fee 100644 --- a/libmudflap/mf-runtime.c +++ b/libmudflap/mf-runtime.c @@ -1079,24 +1079,80 @@ __mf_uncache_object (__mf_object_t *old_obj) /* 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; + } + } + } + } } } |