perf(parser): move kinds field of Modifiers to first

[overlookmotel]

Tiny perf optimization. Re-order fields of Modifiers to put kinds first (offset 0), as it's far more often accessed than offsets field. This removes the need for offsetting when accessing Modifier::kinds - a pointer to Modifers is a pointer to kinds.

[overlookmotel]

• perf(parser): move kinds field of Modifiers to first #20833 👈 (View in Graphite)
• perf(parser): add Modifiers::contains_accessibility #20832
• perf(parser): make Modifiers::accessibility branchless #20827
• perf(parser): add #[inline] to trivial modifier methods #20826
• perf(parser): defer calculation of Modifier spans #20823 : 1 other dependent PR (#20824 )
• perf(parser): remove branch from parse_modifiers #20821
• perf(parser): reduce Kind to ModifierKind conversions in eat_modifiers_before_declaration #20820
• refactor(parser): shorten code handling illegal modifiers #20781
• perf(parser): fast path for no syntax errors when checking modifiers #20748
• perf(parser): remove a lookahead from eat_modifiers_before_declaration #20755
• refactor(parser): nest modifiers types in modules #20754
• refactor(parser): re-order modifiers code #20753
• perf(parser): store Modifiers on stack #20742
• perf(parser): add Modifiers::get method #20741
• refactor(parser): rename ModifierKinds::empty to none #20740
• refactor(parser): rename ModifierFlags to ModifierKinds #20739
• refactor(parser): simplify ModifierFlags #20738
• refactor(parser): import from std at top level #20737
• refactor(parser): remove Modifier::is_static() #20736
• refactor(parser): remove dead code from modifier parsing #20735
• main

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[Copilot]

Pull request overview

Reorders fields in Modifiers to place the frequently accessed kinds bitfield at offset 0 for a small parser performance optimization.

Changes:

• Add #[repr(C)] and reorder Modifiers fields so kinds is first.
• Update Modifiers::empty() initializer order to match the new field layout.

[codspeed-hq]

Merging this PR will not alter performance

✅ 48 untouched benchmarks
⏩ 8 skipped benchmarks¹

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_{Comparing om/03-28-perf_parser_move_kinds_field_of_modifiers_to_first (f72f108) with om/03-29-perf_parser_add_modifiers_contains_accessibility_ (2a06835)}

Footnotes

1. 8 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[camc314]

Merge activity

• Mar 29, 3:34 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 29, 3:40 PM UTC: The Graphite merge queue removed this pull request due to removal of a downstack PR #20820.
• Mar 29, 3:40 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 29, 3:41 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 29, 3:41 PM UTC: The merge label '0-merge' was removed. This PR will no longer be merged by the Graphite merge queue
• Mar 29, 3:42 PM UTC: camc314 added this pull request to the Graphite merge queue.
• Mar 29, 4:19 PM UTC: The Graphite merge queue removed this pull request due to downstack failures on PR #20820.
• Mar 29, 4:47 PM UTC: The merge label '0-merge' was detected. This PR will be added to the Graphite merge queue once it meets the requirements.
• Mar 29, 4:52 PM UTC: graphite-app added this pull request to the Graphite merge queue.
• Mar 29, 4:55 PM UTC: Merged by the Graphite merge queue.