Aliaksandr Kalenik eb210bb3af LibWeb: Replace OrderedHashMap with page-table Vector in LayoutState ...

Each NodeWithStyle is assigned a sequential layout index during the
pre-layout tree traversal. LayoutState stores UsedValues in a
PagedStore — a two-level page table indexed by layout_index that
gives O(1) lookup via two array accesses, with pages allocated
lazily on first write. UsedValues are stored directly in pages
(Optional<T>) rather than behind heap pointers, eliminating
per-entry malloc/free calls and improving cache locality.

This cuts ensure_used_values_for() from ~14% to ~7% in profiles
on https://www.nyan.cat/.

2026-02-23 01:13:35 +01:00

37 KiB

Raw Blame History

View Raw