feat: improve segment check logic#10
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not-matthias merged 3 commits intoMay 20, 2026
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May 20, 2026
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- refactor(debuginfo): use find_rx_mapping for fallback DI lookup
- test(callgrind): smoke-test VG_(find_DebugInfo) attribution
Merging this PR will degrade performance by 12.3%
Warning Please fix the performance issues or acknowledge them on CodSpeed. Performance Changes
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GuillaumeLagrange
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May 20, 2026
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lgtm, we'll be able to release this soon IMO
The fallback added in 938e424 used VG_(am_find_nsegment) + VG_(am_get_filename) + strcmp against each DI's fsm.filename. Replace it with ML_(find_rx_mapping)(di, a, a), which walks the same set of rx mappings already recorded for each DebugInfo and keeps a per-DI single-entry cache (last_rx_map), so the hot path is O(1). No coverage change for BOLT-style binaries: both R-E PT_LOADs are recorded as rx DebugInfoMappings during ELF acceptance, so the loop finds them just as well as the filename match did. Also emit a Vg_DebugMsg trace when the fallback fires (only with -v -v).
Add a tiny C program with hot_fn in .text plus warm_fn/cold_fn in orphan executable sections (warm_code/cold_code) that sit in the same R-E LOAD but outside text_avma..text_avma+text_size. The .vgtest compares the resolved ob= basenames against an expected list, verifying callgrind attributes events to the test binary even when execution leaves .text.
Drop the explicit CODSPEED_PERF_ENABLED=false override so the CodSpeed action runs with its default perf integration.
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