coverage: Remove pending_dups from the span refiner
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coverage: Remove `pending_dups` from the span refiner When extracting coverage spans from a function's MIR, we need to decide how to handle spans that are associated with more than one node (BCB) in the coverage control flow graph. The existing code for managing those duplicate spans is very subtle and difficult to modify. But by eagerly deduplicating those extracted spans in a much simpler way, we can remove a massive chunk of complexity from the span refiner. There is a tradeoff here, in that we no longer try to retain *all* nondominating BCBs that have the same span, only the last one in the (semi-arbitrary) dominance ordering. But in practice, this produces very little difference in our coverage tests, and the simplification is so significant that I think it's worthwhile. `@rustbot` label +A-code-coverage
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…iaskrgr Rollup of 6 pull requests Successful merges: - rust-lang#119636 (os::net: expanding TcpStreamExt for Linux with `tcp_deferaccept`.) - rust-lang#121261 (coverage: Remove `pending_dups` from the span refiner) - rust-lang#121336 (triagebot: add queue notifications) - rust-lang#121391 (never patterns: Fix liveness analysis in the presence of never patterns) - rust-lang#121399 (Solaris linker does not support --strip-debug) - rust-lang#121406 (Add a couple tests) Failed merges: - rust-lang#121206 (Top level error handling) r? `@ghost` `@rustbot` modify labels: rollup
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…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#121206 (Top level error handling) - rust-lang#121261 (coverage: Remove `pending_dups` from the span refiner) - rust-lang#121336 (triagebot: add queue notifications) - rust-lang#121373 (Consistently refer to a test's `revision` instead of `cfg`) - rust-lang#121391 (never patterns: Fix liveness analysis in the presence of never patterns) - rust-lang#121392 (Unify dylib loading between proc macros and codegen backends) - rust-lang#121399 (Solaris linker does not support --strip-debug) - rust-lang#121406 (Add a couple tests) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#121261 - Zalathar:pending-dups, r=oli-obk coverage: Remove `pending_dups` from the span refiner When extracting coverage spans from a function's MIR, we need to decide how to handle spans that are associated with more than one node (BCB) in the coverage control flow graph. The existing code for managing those duplicate spans is very subtle and difficult to modify. But by eagerly deduplicating those extracted spans in a much simpler way, we can remove a massive chunk of complexity from the span refiner. There is a tradeoff here, in that we no longer try to retain *all* nondominating BCBs that have the same span, only the last one in the (semi-arbitrary) dominance ordering. But in practice, this produces very little difference in our coverage tests, and the simplification is so significant that I think it's worthwhile. ``@rustbot`` label +A-code-coverage
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When extracting coverage spans from a function's MIR, we need to decide how to handle spans that are associated with more than one node (BCB) in the coverage control flow graph.
The existing code for managing those duplicate spans is very subtle and difficult to modify. But by eagerly deduplicating those extracted spans in a much simpler way, we can remove a massive chunk of complexity from the span refiner.
There is a tradeoff here, in that we no longer try to retain all nondominating BCBs that have the same span, only the last one in the (semi-arbitrary) dominance ordering. But in practice, this produces very little difference in our coverage tests, and the simplification is so significant that I think it's worthwhile.
@rustbot label +A-code-coverage