commit 8185e47822465a5c7a9cc6e56a11f16996855d79
author Raph Levien <raph@google.com> Thu Oct 25 23:11:13 2012 -0700
committer Raph Levien <raph@google.com> Fri Oct 26 16:09:22 2012 -0700
tree a3faed051d830bd856e0c59fef93b8187a3f2bf9
parent ba0b9cca697a84947c08983338ce4e7f30920fd8

Add an LRU cache plus hashing primitives

This patch adds a hashtable-based LRU cache. This should be
significantly higher performance than the GenerationCache it is intended
to replace. It is a large part of the fix for bug 7271109
TextLayoutCache low-level performance issues.

We added a new method to BasicHashtable to detect when rehashing is
needed, because the internal linked list pointers would get invalidated
by that rehashing.

Also, the hash_type specialized to pointers had a small flaw.

Change-Id: I950c2083f96519777b851dbe157100e0a334caec

libs/utils/BasicHashtable.cpp

diff --git a/libs/utils/BasicHashtable.cpp b/libs/utils/BasicHashtable.cpp
index fb8ec9f..fd51b7b 100644
--- a/libs/utils/BasicHashtable.cpp
+++ b/libs/utils/BasicHashtable.cpp
@@ -80,7 +80,7 @@
             SharedBuffer* sb = SharedBuffer::bufferFromData(mBuckets);
             if (sb->onlyOwner()) {
                 destroyBuckets(mBuckets, mBucketCount);
-                for (size_t i = 0; i < mSize; i++) {
+                for (size_t i = 0; i < mBucketCount; i++) {
                     Bucket& bucket = bucketAt(mBuckets, i);
                     bucket.cookie = 0;
                 }