GCI: At their def site, actually wfcheck the where-clause & always eval free lifetime-generic constants by fmease · Pull Request #136429 · rust-lang/rust (original) (raw)
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service andprivacy statement. We’ll occasionally send you account related emails.
Already on GitHub?Sign in to your account
Conversation
This file contains hidden or 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
[ Show hidden characters]({{ revealButtonHref }})
1st commit: Partially addresses #136204 by turning const eval errors from post to pre-mono for free lifetime-generic constants.
Re. 2nd commit: Oof, yeah, I missed that in the initial impl!
This doesn't fully address #136204 because I still haven't figured out how & where to properly & best suppress const eval of free constants whose predicates don't hold at the def site. The motivating example is const _UNUSED: () = () where for<'_delay> String: Copy; which can also be found over at the tracking issue #113521.
r? compiler-errors or reassign
Status: Awaiting review from the assignee but also interested parties.
Relevant to the compiler team, which will review and decide on the PR/issue.
labels
This comment has been minimized.
bors added a commit to rust-lang-ci/rust that referenced this pull request
GCI: At their def site, actually wfcheck the where-clause & always eval free lifetime-generic constants
1st commit: Partially addresses rust-lang#136204 by turning const eval errors from post to pre-mono for free lifetime-generic constants. Re. 2nd commit: Oof, that's embarrassing! How could I miss that in the initial impl?
This doesn't fully address rust-lang#136204 because I still haven't figured out how & where to properly & best suppress const eval of free constants whose predicates don't hold at the def site. The motivating example is #![feature(trivial_bounds)] const _UNUSED: () = () where String: Copy; which can also be found over at the tracking issue rust-lang#113521.
r? compiler-errors or reassign
☀️ Try build successful - checks-actions
Build commit: ea1cdda (ea1cdda3b51a1290675800f2196813f4bfc693bd)
This comment has been minimized.
Finished benchmarking commit (ea1cdda): comparison URL.
Overall result: ❌ regressions - please read the text below
Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.
Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.
@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression
Instruction count
This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | 0.9% | [0.4%, 1.1%] | 8 |
| Regressions ❌ (secondary) | 0.3% | [0.3%, 0.3%] | 1 |
| Improvements ✅ (primary) | - | - | 0 |
| Improvements ✅ (secondary) | - | - | 0 |
| All ❌✅ (primary) | 0.9% | [0.4%, 1.1%] | 8 |
Max RSS (memory usage)
Results (primary 1.5%, secondary -2.0%)
This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | 1.5% | [1.0%, 2.0%] | 2 |
| Regressions ❌ (secondary) | - | - | 0 |
| Improvements ✅ (primary) | - | - | 0 |
| Improvements ✅ (secondary) | -2.0% | [-2.0%, -2.0%] | 1 |
| All ❌✅ (primary) | 1.5% | [1.0%, 2.0%] | 2 |
Cycles
This benchmark run did not return any relevant results for this metric.
Binary size
This benchmark run did not return any relevant results for this metric.
Bootstrap: 777.275s -> 776.801s (-0.06%)
Artifact size: 328.69 MiB -> 328.73 MiB (0.01%)
Some changes occurred to the CTFE / Miri interpreter
cc @rust-lang/miri, @rust-lang/wg-const-eval
This comment has been minimized.
bors added a commit to rust-lang-ci/rust that referenced this pull request
GCI: At their def site, actually wfcheck the where-clause & always eval free lifetime-generic constants
1st commit: Partially addresses rust-lang#136204 by turning const eval errors from post to pre-mono for free lifetime-generic constants. Re. 2nd commit: Oof, yeah, I missed that in the initial impl!
This doesn't fully address rust-lang#136204 because I still haven't figured out how & where to properly & best suppress const eval of free constants whose predicates don't hold at the def site. The motivating example is #![feature(trivial_bounds)] const _UNUSED: () = () where String: Copy; which can also be found over at the tracking issue rust-lang#113521.
r? compiler-errors or reassign
☀️ Try build successful - checks-actions
Build commit: 6f11489 (6f11489377389dbe08c91408f1c8f953933c18cd)
This comment has been minimized.
turning const eval errors from post to pre-mono for free lifetime-generic constants.
This should be listed as an item in the tracking issue to make sure it is discussed during stabilization.
Status: This is awaiting some action (such as code changes or more information) from the author.
and removed S-waiting-on-review
Status: Awaiting review from the assignee but also interested parties.
labels
Silences rust-log-analyzer postings to the PR it's added on.
label
Co-authored-by: Michael Goulet michael@errs.io
I've reverted the revert of the perf optimization from #121387 (meaning: we won't use const_eval_poly and we'll continue to pass empty substs instead of identity substs since that didn't seem to affect things negatively (I've left a FIXME ofc)), so marking
@bors rollup-
@rustbot label -perf-regression
With @BoxyUwU currently reworking&fixing wfchecking for type-system consts (and consts in general?) (see #137972, #140549, #140553) and with impossible predicates on const items leading to MIR Unreachables being the hot topic for other people, too, I'd like to postpone that part of issue #136204 and keep the scope of this PR limited / as is.
I don't want to interfere with Boxy's work which might even fix this and if not I'd at least have more time to gain intel on how to best fix it (I remember from February that there was some preexisting issues, like ImpossiblePredicates not considering non-global preds for example).
WDYT?
Status: Awaiting review from the assignee but also interested parties.
and removed S-waiting-on-author
Status: This is awaiting some action (such as code changes or more information) from the author.
Silences rust-log-analyzer postings to the PR it's added on.
labels
This comment has been minimized.
Actually let's perf run as a sanity check cuz I might've modified hot paths here and we're doing a bit more work.
@bors try @rust-timer queue
This comment has been minimized.
bors added a commit to rust-lang-ci/rust that referenced this pull request
GCI: At their def site, actually wfcheck the where-clause & always eval free lifetime-generic constants
1st commit: Partially addresses rust-lang#136204 by turning const eval errors from post to pre-mono for free lifetime-generic constants. Re. 2nd commit: Oof, yeah, I missed that in the initial impl!
This doesn't fully address rust-lang#136204 because I still haven't figured out how & where to properly & best suppress const eval of free constants whose predicates don't hold at the def site. The motivating example is #![feature(trivial_bounds)] const _UNUSED: () = () where String: Copy; which can also be found over at the tracking issue rust-lang#113521.
r? compiler-errors or reassign
☀️ Try build successful - checks-actions
Build commit: 3f34812 (3f348129e6da6289f0ba3825919c2124c4cc6a89)
This comment has been minimized.
This comment has been minimized.
Finished benchmarking commit (3f34812): comparison URL.
Overall result: ❌✅ regressions and improvements - please read the text below
Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR may lead to changes in compiler perf.
Next Steps: If you can justify the regressions found in this try perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please fix the regressions and do another perf run. If the next run shows neutral or positive results, the label will be automatically removed.
@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression
Instruction count
This is the most reliable metric that we have; it was used to determine the overall result at the top of this comment. However, even this metric can sometimes exhibit noise.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | 0.5% | [0.5%, 0.5%] | 1 |
| Regressions ❌ (secondary) | - | - | 0 |
| Improvements ✅ (primary) | -2.8% | [-2.8%, -2.8%] | 1 |
| Improvements ✅ (secondary) | - | - | 0 |
| All ❌✅ (primary) | -1.2% | [-2.8%, 0.5%] | 2 |
Max RSS (memory usage)
Results (primary -0.3%)
This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | 1.4% | [0.5%, 3.0%] | 6 |
| Regressions ❌ (secondary) | - | - | 0 |
| Improvements ✅ (primary) | -0.6% | [-1.9%, -0.4%] | 35 |
| Improvements ✅ (secondary) | - | - | 0 |
| All ❌✅ (primary) | -0.3% | [-1.9%, 3.0%] | 41 |
Cycles
Results (primary -0.1%)
This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | 0.5% | [0.4%, 0.7%] | 8 |
| Regressions ❌ (secondary) | - | - | 0 |
| Improvements ✅ (primary) | -1.0% | [-2.6%, -0.4%] | 5 |
| Improvements ✅ (secondary) | - | - | 0 |
| All ❌✅ (primary) | -0.1% | [-2.6%, 0.7%] | 13 |
Binary size
Results (primary -1.1%)
This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
| mean | range | count | |
|---|---|---|---|
| Regressions ❌ (primary) | - | - | 0 |
| Regressions ❌ (secondary) | - | - | 0 |
| Improvements ✅ (primary) | -1.1% | [-1.1%, -1.1%] | 1 |
| Improvements ✅ (secondary) | - | - | 0 |
| All ❌✅ (primary) | -1.1% | [-1.1%, -1.1%] | 1 |
Bootstrap: 769.081s -> 770.42s (0.17%)
Artifact size: 365.55 MiB -> 365.42 MiB (-0.04%)