commit | d4fc4a8cad0a8f94ea2a8bca7c76cebd8793395c | [log] [tgz] |
---|---|---|
author | mlippautz <mlippautz@chromium.org> | Wed Dec 02 11:43:32 2015 |
committer | Commit bot <commit-bot@chromium.org> | Wed Dec 02 11:43:42 2015 |
tree | 0256ae3f5de496783a1819f2f23db0538eaef947 | |
parent | 09032dade4d062664d497f7e1b0922275c3ad7dc [diff] |
Revert of [heap] Clean up stale store buffer entries for aborted pages. (patchset #4 id:60001 of https://codereview.chromium.org/1493653002/ ) Reason for revert: Not completely correct fix. Original issue's description: > [heap] Clean up stale store buffer entries for aborted pages. > > 1. Let X be the aborted slot (slot in an evacuated object in an aborted page) > 2. Assume X contains pointer to Y and Y is in the new space, so X is in the > store buffer. > 3. Store buffer rebuilding will not filter out X (it checks InNewSpace(Y)). > 4. The current mark-sweep finishes. The slot X is in free space and is also in > the store buffer. > 5. A string of length 9 "abcdefghi" is allocated in the new space. The string > looks like |MAP|LENGTH|hgfedcba|NNNNNNNi| in memory, where NNNNNNN is > previous garbage. Let's assume that NNNNNNN0 was pointing to a new space > object before. > 6. Scavenge happens. > 7. Slot X is still in free space and in store buffer. [It causes scavenge of > the object Y in > store_buffer()->IteratePointersToNewSpace(&Scavenger::ScavengeObject). But > it is not important]. > 8. Our string is promoted and is allocated over the slot X, such that NNNNNNNi > is written in X. > 9. The scavenge finishes. > 9. Another scavenge starts. > 10. We crash in > store_buffer()->IteratePointersToNewSpace(&Scavenger::ScavengeObject) when > processing slot X, because it doesn't point to valid map. > > BUG=chromium:524425,chromium:564498 > LOG=N > R=hpayer@chromium.org, ulan@chromium.org > > Committed: https://crrev.com/2e7eea4aef3403969fe885e30f892d46253b3572 > Cr-Commit-Position: refs/heads/master@{#32495} TBR=hpayer@chromium.org,ulan@chromium.org NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true BUG=chromium:524425,chromium:564498 Review URL: https://codereview.chromium.org/1489243004 Cr-Commit-Position: refs/heads/master@{#32504}
V8 is Google's open source JavaScript engine.
V8 implements ECMAScript as specified in ECMA-262.
V8 is written in C++ and is used in Google Chrome, the open source browser from Google.
V8 can run standalone, or can be embedded into any C++ application.
V8 Project page: https://github.com/v8/v8/wiki
Checkout depot tools, and run
fetch v8
This will checkout V8 into the directory v8
and fetch all of its dependencies. To stay up to date, run
git pull origin gclient sync
For fetching all branches, add the following into your remote configuration in .git/config
:
fetch = +refs/branch-heads/*:refs/remotes/branch-heads/* fetch = +refs/tags/*:refs/tags/*
Please follow the instructions mentioned on the V8 wiki.