diff options
| -rw-r--r-- | compiler-rt/lib/ubsan/ubsan_type_hash.cc | 12 | ||||
| -rw-r--r-- | compiler-rt/lib/ubsan/ubsan_type_hash.h | 11 |
2 files changed, 15 insertions, 8 deletions
diff --git a/compiler-rt/lib/ubsan/ubsan_type_hash.cc b/compiler-rt/lib/ubsan/ubsan_type_hash.cc index 6d04436929a..6630c843cf5 100644 --- a/compiler-rt/lib/ubsan/ubsan_type_hash.cc +++ b/compiler-rt/lib/ubsan/ubsan_type_hash.cc @@ -89,7 +89,7 @@ namespace abi = __cxxabiv1; // (worst-case, we could miss a bug or see a slowdown) but we should // avoid upsetting race detectors. -// Find a bucket to store the given value in. +/// Find a bucket to store the given hash value in. static __ubsan::HashValue *getTypeCacheHashTableBucket(__ubsan::HashValue V) { static const unsigned HashTableSize = 65537; static __ubsan::HashValue __ubsan_vptr_hash_set[HashTableSize] = { 1 }; @@ -107,10 +107,8 @@ static __ubsan::HashValue *getTypeCacheHashTableBucket(__ubsan::HashValue V) { return &__ubsan_vptr_hash_set[V]; } -// A cache of recently-checked hashes. Mini hash table with "random" evictions. -// The bottom 7 bits of the hash are used as the key. -static const unsigned CacheSize = 128; -extern "C" __ubsan::HashValue __ubsan_vptr_type_cache[CacheSize] = { 1 }; +/// A cache of recently-checked hashes. Mini hash table with "random" evictions. +__ubsan::HashValue __ubsan_vptr_type_cache[__ubsan::VptrTypeCacheSize] = { 1 }; /// \brief Determine whether \p Derived has a \p Base base class subobject at /// offset \p Offset. @@ -174,7 +172,7 @@ bool __ubsan::checkDynamicType(void *Object, void *Type, HashValue Hash) { // Check whether this is something we've evicted from the cache. HashValue *Bucket = getTypeCacheHashTableBucket(Hash); if (*Bucket == Hash) { - __ubsan_vptr_type_cache[Hash % CacheSize] = Hash; + __ubsan_vptr_type_cache[Hash % VptrTypeCacheSize] = Hash; return true; } @@ -194,7 +192,7 @@ bool __ubsan::checkDynamicType(void *Object, void *Type, HashValue Hash) { return false; // Success. Cache this result. - __ubsan_vptr_type_cache[Hash % CacheSize] = Hash; + __ubsan_vptr_type_cache[Hash % VptrTypeCacheSize] = Hash; *Bucket = Hash; return true; } diff --git a/compiler-rt/lib/ubsan/ubsan_type_hash.h b/compiler-rt/lib/ubsan/ubsan_type_hash.h index 982ebdfbc26..ac1be4944b8 100644 --- a/compiler-rt/lib/ubsan/ubsan_type_hash.h +++ b/compiler-rt/lib/ubsan/ubsan_type_hash.h @@ -22,7 +22,16 @@ typedef uptr HashValue; /// \brief Check whether the dynamic type of \p Object has a \p Type subobject /// at offset 0. /// \return \c true if the type matches, \c false if not. -bool checkDynamicType(void *Object, void *Type, HashValue CacheSlot); +bool checkDynamicType(void *Object, void *Type, HashValue Hash); + +const unsigned VptrTypeCacheSize = 128; + +/// \brief A cache of the results of checkDynamicType. \c checkDynamicType would +/// return \c true (modulo hash collisions) if +/// \code +/// __ubsan_vptr_type_cache[Hash % VptrTypeCacheSize] == Hash +/// \endcode +extern "C" HashValue __ubsan_vptr_type_cache[VptrTypeCacheSize]; } // namespace __ubsan |
