perf(semantic): single call to Function::bind for functions

[overlookmotel]

Previously visit_function had 2 calls to Function::bind - depending on whether function is a declaration or expression, we called bind before or after entering the scope.

Instead, only have 1 call to Function::bind and enter the scope either before or after it depending on declaration/expression.

The scope is created before call to bind either way, but we just change when we enter that scope depending on the function type.

Hopefully this means that Function::bind can now be inlined into visit_function.

To facilitate this change, move the code for creating a scope out of enter_scope into a new method create_scope. create_scope creates a scope but just doesn't enter it yet.

[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(semantic): single call to Function::bind for functions #18295 👈 (View in Graphite)
• refactor(semantic): move code into if block #18294 : 1 other dependent PR (#18296 )
• perf(semantic): skip parent lookup for function declarations in Function::bind #18293
• perf(semantic): move check for function declaration out of is_function_part_of_if_statement #18292
• perf(semantic): skip checking redeclarations for function expressions #18291
• refactor(semantic): simplify checking if function is part of if statement #18290
• test(semantic): add test cases for function redeclaration check #18288
• main

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[codspeed-hq]

Merging this PR will not alter performance

✅ 42 untouched benchmarks
⏩ 3 skipped benchmarks¹

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_{Comparing om/01-20-perf_semantic_single_call_to_function_bind_for_functions (d0f8dc7) with om/01-20-refactor_semantic_move_code_into_if_block (7853545)}

Footnotes

1. 3 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 refactors semantic scope handling for functions to reduce duplicate work and enable better inlining, while preserving existing binding semantics for function declarations vs expressions.

Changes:

• Introduces SemanticBuilder::create_scope to construct a scope (including unresolved reference stack management) without immediately entering it.
• Updates Visit for SemanticBuilder::enter_scope to delegate to create_scope, preserving previous behavior.
• Refactors visit_function to:
  • Apply strict mode flags once,
  • Create the function scope once via create_scope,
  • Call Function::bind exactly once while maintaining the existing behavior of binding declarations in the parent scope and expressions in the function’s own scope.

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[overlookmotel]

Doesn't produce the desired perf improvement! 🤷

It makes the code more complicated, and has no apparent benefit, so closing.