perf(parser): allocate AST nodes in arena directly

[overlookmotel]

Same as #23709.

Small perf optimizations around AST builder calls.

• AST nodes which end up in Boxes, allocate into the Box as early as possible, to increase chance compiler sees the type can be built directly in arena, rather than built on the stack, and then copied from stack into arena.
• Functions return Box<T> rather than T where the value needs to be boxed anyway. If function is not inlined, this avoids stack allocation + copy.

Also, shorten code where possible by using more specific AstBuilder methods.

[overlookmotel]

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This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• perf(transformer/object-rest-spread): reduce iteration #23720
• perf(transformer): allocate AST nodes in arena directly #23711
• perf(parser): allocate AST nodes in arena directly #23712 👈 (View in Graphite)
• perf(minifier): allocate AST nodes in arena directly #23710
• perf(isolated_declarations): allocate AST nodes in arena directly #23709
• refactor(ast): remove AstBuilder::alloc calls #23708
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 62 untouched benchmarks
⏩ 9 skipped benchmarks¹

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_{Comparing om/06-21-perf_parser_allocate_ast_nodes_in_arena_directly (b57ac10) with om/06-21-perf_minifier_allocate_ast_nodes_in_arena_directly (644b3d0)}

Footnotes

1. 9 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. ↩

[Copilot]

Pull request overview

This PR applies small performance-focused refactors in oxc_parser to allocate AST nodes directly in the arena (and/or return already-boxed nodes) to reduce intermediate stack allocations and copies during parsing.

Changes:

• Return Box<'a, T> from several parsing helpers when the produced AST node is always boxed in the AST (e.g. literals, using declarations, TS import attributes object).
• Replace “build then alloc” patterns with AstBuilder::alloc_* constructors (e.g. alloc_identifier_name, alloc_object_expression, alloc_*_literal).
• Thread boxed nodes through call sites to avoid extra self.alloc(...) steps.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
crates/oxc_parser/src/ts/types.rs	Allocate TS import type option/attribute AST nodes directly in the arena; return boxed object expressions where required.
crates/oxc_parser/src/js/statement.rs	Pass already-boxed using declarations into parse_any_for_loop without re-boxing.
crates/oxc_parser/src/js/expression.rs	Return boxed literal nodes and construct Expression::*Literal variants without intermediate allocations.
crates/oxc_parser/src/js/declaration.rs	Make parse_using_declaration return a boxed VariableDeclaration and propagate that to statement construction.
crates/oxc_parser/src/js/binding.rs	Make rest-element parsing return boxed rest elements and pass them through binding-pattern builders directly.
crates/oxc_parser/src/cursor.rs	Update parse_delimited_list_with_rest to return an optional boxed rest element to match binding parser changes.