AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Fix the logic that should ensure that a string cannot have

Browse Source 
a hash key of zero.
Review URL: http://codereview.chromium.org/9113006

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10338 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
erik.corry@gmail.com 2012-01-05 10:18:28 +00:00
parent 1327cb0acd
commit ea3a515d9d
3 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/objects-inl.h
View File

@ -4381,7 +4381,7 @@ uint32_t StringHasher::GetHash() {
result += (result << 3);
result ^= (result >> 11);
result += (result << 15);
if (result == 0) {
if ((result & String::kHashBitMask) == 0) {
result = 27;
}
return result;

2
src/objects.cc
View File

@ -11444,7 +11444,7 @@ class TwoCharHashTableKey : public HashTableKey {
hash += hash << 3;
hash ^= hash >> 11;
hash += hash << 15;
if (hash == 0) hash = 27;
if ((hash & String::kHashBitMask) == 0) hash = 27;
#ifdef DEBUG
StringHasher hasher(2, seed);
hasher.AddCharacter(c1);

4
src/objects.h
View File

@ -6459,6 +6459,10 @@ class String: public HeapObject {
// Shift constant retrieving hash code from hash field.
static const int kHashShift = kNofHashBitFields;
// Only these bits are relevant in the hash, since the top two are shifted
// out.
static const uint32_t kHashBitMask = 0xffffffffu >> kHashShift;
// Array index strings this short can keep their index in the hash
// field.
static const int kMaxCachedArrayIndexLength = 7;