solidjs / solid / 39111909301

78%

main: 89%

push

github

perf(signals): root owners declare their flags slot from birth (#4136)

disposeChildren writes `_flags` on every owner it kills. The root literal in
createOwner declared `_config` and `_childCount` but not `_flags`, so for
every root — every createRoot, every mapArray row and cell owner — the first
write added a property: a map transition and an out-of-object properties
store per root, at teardown. The allocation profile with inlining disabled
placed the whole of disposal's 12 KB/run and most of its 118 µs in
disposeChildren's own frame; the slot was the only field it writes that a
root did not have.

uibench, call profiler on the unminified fixture (µs, two interleaved
rounds): table/[100,4]/removeAll 165 -> 50–55 (Vapor 55), tree/[500]/removeAll
270 -> 75–80 (Vapor 155), tree/[50,10]/removeAll 300 -> 80 (Vapor 134),
table/[100,4]/filter/4 70 -> 35–40, tree/[500]/[removeFirst(1)] 45 -> 40.
disposeChildren 118 -> 18 µs, its allocation 12 KB -> 0.2 KB per run.

uibench through the board runner, oracle identical (96 cases, 32,543 shared
identities): removeAll family 0.36x, filters 0.56x, single insert/remove/move
0.78x, renders/reverse/worst cases unchanged; Solid ÷ Vapor 1.48 -> 1.14 over
the 96 cases. js-framework: clear -3%, others within noise.

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

756 of 1050 branches covered (72.0%)

Branch coverage included in aggregate %.

1097 of 1339 relevant lines covered (81.93%)

27.83 hits per line