Defer allocating symbol in IdentifierTable::createNotUniquedSymbol #1655
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Summary: We currently allocate this symbol at the top of the function, before performing potential allocations. In theory, the GC could free the newly allocated symbol when we allocate the string. In practice, this does not seem to be possible to trigger, because the new entry will not pass the `isNonLazyStringPrim` check in `IdentifierTable::freeUnmarkedSymbols`. The entry will either still be a free list entry, or will be zero initialized by `lookupVector_.emplace_back` if it was just allocated. Either way, it will not appear to be a "non-lazy" string primitive. Differential Revision: D72269786
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This pull request was exported from Phabricator. Differential Revision: D72269786 |
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Summary:
We currently allocate this symbol at the top of the function, before
performing potential allocations. In theory, the GC could free the newly
allocated symbol when we allocate the string.
In practice, this does not seem to be possible to trigger, because the
new entry will not pass the
isNonLazyStringPrimcheck inIdentifierTable::freeUnmarkedSymbols. The entry will either still be afree list entry, or will be zero initialized by
lookupVector_.emplace_backif it was just allocated. Either way, itwill not appear to be a "non-lazy" string primitive.
Differential Revision: D72269786