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    Revert of "[heap] Clean up stale store buffer entries for aborted pages."... · 23227681
    mlippautz authored
    Revert of "[heap] Clean up stale store buffer entries for aborted pages." (patchset #3 id:40001 of https://codereview.chromium.org/1494503004/ )
    
    Reason for revert:
    Still failing on GC stress
      https://chromegw.corp.google.com/i/client.v8/builders/V8%20Linux%20-%20gc%20stress/builds/690
    
    Original issue's description:
    > Reland of "[heap] Clean up stale store buffer entries for aborted pages."
    >
    > This reverts commit d4fc4a8c.
    >
    > 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/fc6ff534003480e49dc481d9c665e961ab709c02
    > Cr-Commit-Position: refs/heads/master@{#32514}
    
    TBR=hpayer@chromium.org,ulan@chromium.org
    NOPRESUBMIT=true
    NOTREECHECKS=true
    NOTRY=true
    BUG=chromium:524425, chromium:564498
    
    Review URL: https://codereview.chromium.org/1492823002
    
    Cr-Commit-Position: refs/heads/master@{#32520}
    23227681
spaces.h 103 KB