perf(parser): optimize expect() to reduce branch misprediction #14242
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Split the error handling path from the hot path in expect() and expect_without_advance() functions to improve branch prediction. The CPU can now better predict the common success path. Changes: - Add #[cold] #[inline(never)] handle_expect_failure() for error handling - Refactor expect() to inline success path and separate error path - Add #[inline] to expect_without_advance() for consistency - Maintain same behavior while improving performance This addresses the high branch misprediction shown by callgrind profiling. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Pull Request Overview
Optimize the expect() and expect_without_advance() functions to reduce branch misprediction by separating the hot path (success case) from the cold path (error handling).
- Extract error handling into a separate
#[cold] #[inline(never)]function - Inline the success path in both
expect()andexpect_without_advance() - Add appropriate inlining attributes for performance optimization
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Split the error handling path from the hot path in expect() and expect_without_advance() functions to improve branch prediction. The CPU can now better predict the common success path.
Changes:
This addresses the high branch misprediction shown by callgrind profiling.
🤖 Generated with Claude Code