Reland "[heap] Store size with invalidated object"
This is a reland of commit 5d235def The previous version of this CL got reverted because the cached size of an invalidated object wasn't up-to-date when performing a GC. Not all size changes go through NotifyObjectLayoutChange, so https://crrev.com/c/3607992 introduced NotifyObjectSizeChange as a bottleneck for object size changes/right-trimming. This method is now used to update the size of invalidated objects. Original change's description: > [heap] Store size with invalidated object > > When updating pointers during a full GC, a page might not be swept > already. In such cases there might be invalid objects and slots recorded > in free memory. Updating tagged slots in free memory is fine even though > it is superfluous work. > > However, the GC also needs to calculate the size of potentially dead > invalid objects in order to be able to check whether a slot is within > that object. But since that object is dead, its map might be dead as > well which makes size calculation impossible on such objects. The CL > changes this to cache the size of invalid objects. A follow-up CL will > also check the marking bit of invalid objects. > > Bug: v8:12578, chromium:1316289 > Change-Id: Ie773d0862a565982957e0dc409630d76552d1a32 > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3599482 > Reviewed-by: Michael Lippautz <mlippautz@chromium.org> > Reviewed-by: Jakob Linke <jgruber@chromium.org> > Reviewed-by: Patrick Thier <pthier@chromium.org> > Commit-Queue: Dominik Inführ <dinfuehr@chromium.org> > Cr-Commit-Position: refs/heads/main@{#80169} Bug: v8:12578, chromium:1316289 Change-Id: I1f7c6070b8e7d116aeb1a8d03d4f87927ab40872 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3608632Reviewed-by: Jakob Linke <jgruber@chromium.org> Reviewed-by: Patrick Thier <pthier@chromium.org> Commit-Queue: Dominik Inführ <dinfuehr@chromium.org> Reviewed-by: Michael Lippautz <mlippautz@chromium.org> Cr-Commit-Position: refs/heads/main@{#80262}
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