coverage: Remove pending_dups from the span refiner
#121261
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
rustbot
added
S-waiting-on-review
|
Some changes occurred to MIR optimizations cc @rust-lang/wg-mir-opt |
rustbot
added
the
A-code-coverage
This comment has been minimized.
This comment has been minimized.
Zalathar
force-pushed
the
pending-dups
branch
2 times, most recently
from
776684b
to
0cf9973
Compare
Zalathar
force-pushed
the
pending-dups
branch
from
0cf9973
to
3a83b27
Compare
bors
added
S-waiting-on-bors
matthiaskrgr
added a commit
to matthiaskrgr/rust
that referenced
this pull request
Feb 21, 2024
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
bors
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Feb 21, 2024
…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
bors
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Feb 22, 2024
…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
rust-timer
added a commit
to rust-lang-ci/rust
that referenced
this pull request
Feb 22, 2024
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
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
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