feat(ecmascript): add known-globals to side-effect-free property reads

[Dunqing]

Summary

close: #13067

Part of #19673

Depends on #20217.

Port known-globals lists from Rolldown to Oxc's side-effect detection:

• Global identifiers (Math, Array, console, DOM classes, etc.) are now considered side-effect-free to access via is_known_global_identifier, matching Rolldown's GLOBAL_IDENT set
• Property reads like Math.PI, console.log, Object.keys are considered side-effect-free via is_known_global_property
• 3-level chains like Object.prototype.hasOwnProperty are supported via is_known_global_property_deep

Test plan

• Added tests for known global identifiers (Math, Array, Object, console, etc.)
• Added tests for known global property reads (Math.PI, Object.keys, etc.)
• Added tests for 3-level chains (Object.prototype.hasOwnProperty, etc.)
• Existing minifier test expectations updated for improved side-effect detection
• All existing tests pass

🤖 Generated with Claude Code

[Dunqing]

• fix(ecmascript): enhance side-effect detection for classes, TypedArrays, computed members, and spread #20213
• feat(ecmascript): add known-globals to side-effect-free property reads #20212 👈 (View in Graphite)
• feat(ecmascript): add property_write_side_effects to MayHaveSideEffectsContext #20217
• main

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[Copilot]

Pull request overview

Ports Rolldown-style “known globals” knowledge into Oxc’s side-effect detection so the minifier/DCE can treat certain global identifier accesses and global property reads as side-effect-free, enabling more aggressive reductions and updating tests accordingly.

Changes:

• Mark accesses to a large set of known global identifiers as side-effect-free (and add support for known global property reads + select 3-level chains).
• Add property_write_side_effects() to the side-effects context and implement MayHaveSideEffects for AssignmentExpression / UpdateExpression.
• Update and extend minifier test expectations to reflect improved side-effect detection.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
crates/oxc_ecmascript/src/side_effects/expressions.rs	Adds known-global identifier/property handling and new assignment/update side-effect logic.
crates/oxc_ecmascript/src/side_effects/context.rs	Introduces property_write_side_effects() hook on the side-effects context.
crates/oxc_minifier/tests/ecmascript/may_have_side_effects.rs	Adds tests for known globals/property reads/deep chains and updates expectations.
crates/oxc_minifier/tests/peephole/substitute_alternate_syntax.rs	Updates expected outputs enabled by improved purity detection.
crates/oxc_minifier/tests/peephole/oxc.rs	Updates integration expectation based on new optimizations.
crates/oxc_minifier/tests/peephole/inline_single_use_variable.rs	Updates keep-names related expectations for inlining behavior.

[codspeed-hq]

Merging this PR will degrade performance by 6.3%

❌ 1 regressed benchmark
✅ 52 untouched benchmarks
⏩ 3 skipped benchmarks¹

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
❌	Simulation	minifier[react.development.js]	2.6 ms	2.8 ms	-6.3%

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_{Comparing fix/known-globals-side-effects (4d3b18e) with feat/property-write-side-effects (cb8b1f6)}

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. ↩

[graphite-app]

Merge activity

• Mar 12, 9:18 AM UTC: Boshen added this pull request to the Graphite merge queue.
• Mar 12, 9:34 AM UTC: Merged by the Graphite merge queue.