Bug 266098
| Summary: | Reduce necessary bits in some compact pointer encodings | ||
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| Product: | WebKit | Reporter: | David Degazio <d_degazio> |
| Component: | JavaScriptCore | Assignee: | David Degazio <d_degazio> |
| Status: | RESOLVED FIXED | ||
| Severity: | Normal | CC: | webkit-bug-importer |
| Priority: | P2 | Keywords: | InRadar |
| Version: | WebKit Nightly Build | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
David Degazio
rdar://119397319
In a few places in the code, we use an ad-hoc compact pointer tuple encoding separate from WTF::CompactPointerTuple, to store a small payload in the unused space of a pointer. Currently, we assume pointers never exceed 48 bits in width, and reserve a 16 bit payload by shifting the pointer up. However, we only actually need about a byte of space in each of these places. Let's modify these to shift the payload upwards, so the pointer is easier to decode, and we don't claim more space than we need.
| Attachments | ||
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| Add attachment proposed patch, testcase, etc. |
David Degazio
Pull request: https://github.com/WebKit/WebKit/pull/21532
EWS
Committed 271789@main (8b1288d0a44b): <https://commits.webkit.org/271789@main>
Reviewed commits have been landed. Closing PR #21532 and removing active labels.