In `pretty_print_type()`, print `async fn` futures' paths instead of spans. #122923

kpreid · 2024-03-23T02:25:01Z

This makes -Zprint-type-sizes's output easier to read, because the name of an async fn is more immediately recognizable than its span. This change will also synergize with my other -Zprint-type-sizes PR #122922 which prints the type of child futures being awaited.

I also deleted the comment "FIXME(eddyb) should use def_span." because it appears to have already been fixed by commit 67727aa.

rustbot · 2024-03-23T02:25:08Z

r? @petrochenkov

rustbot has assigned @petrochenkov.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

compiler-errors

I don't mind this approach, but I think it needs some sort of delimiter to separate the "async fn body" part and the def path - {async fn body operation} is hard to parse over, e.g. {async fn body @ operation} or {async fn body - operation} something.

kpreid · 2024-03-23T02:39:01Z

I don't mind this approach, but I think it needs some sort of delimiter to separate the "async fn body" part and the def path - {async fn body operation} is hard to parse over, e.g. {async fn body @ operation} or {async fn body - operation} something.

I was having that concern myself, but I couldn't think of a really good syntax. The "@" seems appropriate to keep only where it is currently used: before a span. How about {async fn body of: operation}? Maybe with function call parens?

compiler-errors · 2024-03-23T02:41:20Z

of and : together seems a bit excessive. I think : is probably fine on its own. parens are fine i guess too

compiler-errors · 2024-03-23T02:42:46Z

Given this change is a bit more involved, I'm gonna cc @rust-lang/wg-diagnostics to see if anyone has thoughts. Given it's friday, I'm happy to r+ this on like monday or tuesday.

kpreid · 2024-03-23T02:43:38Z

A colon can have lots of meanings. My intuition about including the actual English word "of" is that new readers really don't know what all this punctuation and terminology means, and including "of" makes it much closer to immediately clear what we are talking about: this type is the "async fn body" of the named function.

kpreid · 2024-03-23T03:13:38Z

I pushed a new version which prints like {async fn body of name()}, or in a more complex example from tests/ui/async-await/future-sizes/async-awaiting-fut.stdout,

std::mem::MaybeUninit<{async fn body of calls_fut<{async fn body of big_fut()}>()}>

I think that reads pretty well — the lack of turbofish isn't my fault. 😁

-Zprint-type-sizes: print the types of awaitees and unnamed coroutine locals. This should assist comprehending the size of coroutines. In particular, whenever a future is suspended while awaiting another future, the latter is given the special name `__awaitee`, and now the type of the awaited future will be printed, allowing identifying caller/callee — er, I mean, poller/pollee — relationships. It would be possible to include the type name in more cases, but I thought that that might be overly verbose (`print-type-sizes` is already a lot of text) and ordinary named fields or variables are easier for readers to discover the types of. This change will also synergize with my other PR rust-lang#122923 which changes type printing to print the path of the `async fn` instead of the span. Implementation note: I'm not sure if `Symbol::intern` is appropriate for this application, but it was the obvious way to not have to remove the `Copy` implementation from `FieldInfo`, or add a `'tcx` lifetime, while avoiding keeping a lot of possibly redundant strings in memory. I don't know what the proper tradeoff to make here is (though presumably it is not too important for a `-Z` debugging option).

Rollup merge of rust-lang#122922 - kpreid:print-async, r=compiler-errors -Zprint-type-sizes: print the types of awaitees and unnamed coroutine locals. This should assist comprehending the size of coroutines. In particular, whenever a future is suspended while awaiting another future, the latter is given the special name `__awaitee`, and now the type of the awaited future will be printed, allowing identifying caller/callee — er, I mean, poller/pollee — relationships. It would be possible to include the type name in more cases, but I thought that that might be overly verbose (`print-type-sizes` is already a lot of text) and ordinary named fields or variables are easier for readers to discover the types of. This change will also synergize with my other PR rust-lang#122923 which changes type printing to print the path of the `async fn` instead of the span. Implementation note: I'm not sure if `Symbol::intern` is appropriate for this application, but it was the obvious way to not have to remove the `Copy` implementation from `FieldInfo`, or add a `'tcx` lifetime, while avoiding keeping a lot of possibly redundant strings in memory. I don't know what the proper tradeoff to make here is (though presumably it is not too important for a `-Z` debugging option).

compiler-errors · 2024-03-23T18:53:09Z

ok we'll that's basically consensus

@bors r+

bors · 2024-03-23T18:53:11Z

📌 Commit 3743e3e has been approved by compiler-errors

It is now in the queue for this repository.

kpreid · 2024-03-23T19:19:51Z

Rebased and re-blessed on top of #122922 which uses this printing routine more often.

compiler-errors · 2024-03-23T19:23:07Z

@bors r+

bors · 2024-03-23T19:23:10Z

📌 Commit b6b5745 has been approved by compiler-errors

It is now in the queue for this repository.

…-errors In `pretty_print_type()`, print `async fn` futures' paths instead of spans. This makes `-Zprint-type-sizes`'s output easier to read, because the name of an `async fn` is more immediately recognizable than its span. This change will also synergize with my other `-Zprint-type-sizes` PR rust-lang#122922 which prints the type of child futures being awaited. I also deleted the comment "FIXME(eddyb) should use `def_span`." because it appears to have already been fixed by commit 67727aa.

…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#120557 (Add rust-lldb pretty printing for Path and PathBuf) - rust-lang#121051 (Introduce infrastructure for generating target docs) - rust-lang#122892 (fix(bootstrap/dist): use versioned dirs when vendoring) - rust-lang#122896 (Update stdarch submodule) - rust-lang#122923 (In `pretty_print_type()`, print `async fn` futures' paths instead of spans.) - rust-lang#122970 (Use `chunk_by` when building `ReverseSccGraph`) - rust-lang#123003 (CFI: Handle dyn with no principal) r? `@ghost` `@rustbot` modify labels: rollup

…-errors In `pretty_print_type()`, print `async fn` futures' paths instead of spans. This makes `-Zprint-type-sizes`'s output easier to read, because the name of an `async fn` is more immediately recognizable than its span. This change will also synergize with my other `-Zprint-type-sizes` PR rust-lang#122922 which prints the type of child futures being awaited. I also deleted the comment "FIXME(eddyb) should use `def_span`." because it appears to have already been fixed by commit 67727aa.

…iaskrgr Rollup of 8 pull requests Successful merges: - rust-lang#122802 (Provide structured suggestion for unconstrained generic constant) - rust-lang#122858 (Tweak `parse_dot_suffix_expr`) - rust-lang#122923 (In `pretty_print_type()`, print `async fn` futures' paths instead of spans.) - rust-lang#122990 (Clarify transmute example) - rust-lang#122995 (Clean up unnecessary headers/flags in coverage mir-opt tests) - rust-lang#123003 (CFI: Handle dyn with no principal) - rust-lang#123005 (CFI: Support complex receivers) - rust-lang#123020 (Temporarily remove nnethercote from the review rotation.) r? `@ghost` `@rustbot` modify labels: rollup

matthiaskrgr · 2024-03-25T06:46:07Z

needs rebase I think #123023 (comment)
@bors r-

-Zprint-type-sizes: print the types of awaitees and unnamed coroutine locals. This should assist comprehending the size of coroutines. In particular, whenever a future is suspended while awaiting another future, the latter is given the special name `__awaitee`, and now the type of the awaited future will be printed, allowing identifying caller/callee — er, I mean, poller/pollee — relationships. It would be possible to include the type name in more cases, but I thought that that might be overly verbose (`print-type-sizes` is already a lot of text) and ordinary named fields or variables are easier for readers to discover the types of. This change will also synergize with my other PR rust-lang#122923 which changes type printing to print the path of the `async fn` instead of the span. Implementation note: I'm not sure if `Symbol::intern` is appropriate for this application, but it was the obvious way to not have to remove the `Copy` implementation from `FieldInfo`, or add a `'tcx` lifetime, while avoiding keeping a lot of possibly redundant strings in memory. I don't know what the proper tradeoff to make here is (though presumably it is not too important for a `-Z` debugging option).

…spans. This makes `-Zprint-type-sizes`'s output easier to read, because the name of an `async fn` is more immediately recognizable than its span. I also deleted the comment "FIXME(eddyb) should use `def_span`." because it appears to have already been fixed by commit 67727aa.

kpreid · 2024-03-25T15:13:46Z

needs rebase I think #123023 (comment)

Not actually a conflict (I think) but there was a file that hadn't gotten blessed before because I was having an unrelated problem actually finishing the run of tests/mir-opt. Sorry for the trouble. Fixed.

Nilstrieb · 2024-03-25T18:53:07Z

@bors r=compiler-errors

bors · 2024-03-25T18:53:09Z

📌 Commit 3010fa9 has been approved by compiler-errors

It is now in the queue for this repository.

…-errors In `pretty_print_type()`, print `async fn` futures' paths instead of spans. This makes `-Zprint-type-sizes`'s output easier to read, because the name of an `async fn` is more immediately recognizable than its span. This change will also synergize with my other `-Zprint-type-sizes` PR rust-lang#122922 which prints the type of child futures being awaited. I also deleted the comment "FIXME(eddyb) should use `def_span`." because it appears to have already been fixed by commit 67727aa.

…kingjubilee Rollup of 10 pull requests Successful merges: - rust-lang#122707 (Fix a typo in the alloc::string::String docs) - rust-lang#122769 (extend comments for reachability set computation) - rust-lang#122892 (fix(bootstrap/dist): use versioned dirs when vendoring) - rust-lang#122896 (Update stdarch submodule) - rust-lang#122923 (In `pretty_print_type()`, print `async fn` futures' paths instead of spans.) - rust-lang#122950 (Add regression tests for rust-lang#101903) - rust-lang#122958 (Port backtrace dylib-dep test to a ui test) - rust-lang#123039 (Update books) - rust-lang#123044 (`Instance` is `Copy`) - rust-lang#123051 (did I mention that tests are super cool? ) r? `@ghost` `@rustbot` modify labels: rollup

scottmcm · 2024-03-25T22:26:08Z

tests/mir-opt/building/async_await.b-{closure#0}.coroutine_resume.0.mir

    let _24: ();
    let mut _25: std::task::Poll<()>;
-    let mut _26: std::pin::Pin<&mut {async fn body@$DIR/async_await.rs:12:14: 12:16}>;
-    let mut _27: &mut {async fn body@$DIR/async_await.rs:12:14: 12:16};
-    let mut _28: &mut {async fn body@$DIR/async_await.rs:12:14: 12:16};


🎉 for anything that gets line numbers out of mir-opt tests :D

…kingjubilee Rollup of 10 pull requests Successful merges: - rust-lang#122707 (Fix a typo in the alloc::string::String docs) - rust-lang#122769 (extend comments for reachability set computation) - rust-lang#122892 (fix(bootstrap/dist): use versioned dirs when vendoring) - rust-lang#122896 (Update stdarch submodule) - rust-lang#122923 (In `pretty_print_type()`, print `async fn` futures' paths instead of spans.) - rust-lang#122950 (Add regression tests for rust-lang#101903) - rust-lang#123039 (Update books) - rust-lang#123042 (Import the 2021 prelude in the core crate) - rust-lang#123044 (`Instance` is `Copy`) - rust-lang#123051 (did I mention that tests are super cool? ) r? `@ghost` `@rustbot` modify labels: rollup

Rollup merge of rust-lang#122923 - kpreid:print-async-def, r=compiler-errors In `pretty_print_type()`, print `async fn` futures' paths instead of spans. This makes `-Zprint-type-sizes`'s output easier to read, because the name of an `async fn` is more immediately recognizable than its span. This change will also synergize with my other `-Zprint-type-sizes` PR rust-lang#122922 which prints the type of child futures being awaited. I also deleted the comment "FIXME(eddyb) should use `def_span`." because it appears to have already been fixed by commit 67727aa.

rustbot assigned petrochenkov Mar 23, 2024

rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-compiler Relevant to the compiler team, which will review and decide on the PR/issue. labels Mar 23, 2024

kpreid mentioned this pull request Mar 23, 2024

-Zprint-type-sizes: print the types of awaitees and unnamed coroutine locals. #122922

Merged

compiler-errors reviewed Mar 23, 2024

View reviewed changes

This comment has been minimized.

Sign in to view

kpreid force-pushed the print-async-def branch from 2a79ee6 to 3743e3e Compare March 23, 2024 03:07

oli-obk approved these changes Mar 23, 2024

View reviewed changes

estebank approved these changes Mar 23, 2024

View reviewed changes

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. labels Mar 23, 2024

kpreid force-pushed the print-async-def branch from 3743e3e to b6b5745 Compare March 23, 2024 19:18

workingjubilee mentioned this pull request Mar 24, 2024

Rollup of 13 pull requests #122967

Closed

bors added the S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. label Mar 24, 2024

matthiaskrgr mentioned this pull request Mar 24, 2024

Rollup of 7 pull requests #123010

Closed

matthiaskrgr mentioned this pull request Mar 25, 2024

Rollup of 8 pull requests #123023

Closed

bors added S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. and removed S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. labels Mar 25, 2024

kpreid force-pushed the print-async-def branch from aaf49b4 to 3010fa9 Compare March 25, 2024 15:02

bors added S-waiting-on-bors Status: Waiting on bors to run and complete tests. Bors will change the label on completion. and removed S-waiting-on-author Status: This is awaiting some action (such as code changes or more information) from the author. labels Mar 25, 2024

workingjubilee mentioned this pull request Mar 25, 2024

Rollup of 10 pull requests #123054

Closed

workingjubilee mentioned this pull request Mar 25, 2024

Rollup of 10 pull requests #123065

Merged

scottmcm reviewed Mar 25, 2024

View reviewed changes

bors merged commit 9775296 into rust-lang:master Mar 26, 2024
11 checks passed

rustbot added this to the 1.79.0 milestone Mar 26, 2024

kpreid deleted the print-async-def branch March 26, 2024 18:36

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

In `pretty_print_type()`, print `async fn` futures' paths instead of spans. #122923

In `pretty_print_type()`, print `async fn` futures' paths instead of spans. #122923

kpreid commented Mar 23, 2024 •

edited

rustbot commented Mar 23, 2024

compiler-errors left a comment

kpreid commented Mar 23, 2024 •

edited

compiler-errors commented Mar 23, 2024 •

edited

compiler-errors commented Mar 23, 2024

kpreid commented Mar 23, 2024

This comment has been minimized.

kpreid commented Mar 23, 2024

compiler-errors commented Mar 23, 2024

bors commented Mar 23, 2024

kpreid commented Mar 23, 2024

compiler-errors commented Mar 23, 2024

bors commented Mar 23, 2024

matthiaskrgr commented Mar 25, 2024

kpreid commented Mar 25, 2024

Nilstrieb commented Mar 25, 2024

bors commented Mar 25, 2024

scottmcm Mar 25, 2024

In pretty_print_type(), print async fn futures' paths instead of spans. #122923

In pretty_print_type(), print async fn futures' paths instead of spans. #122923

Conversation

kpreid commented Mar 23, 2024 • edited

rustbot commented Mar 23, 2024

compiler-errors left a comment

Choose a reason for hiding this comment

kpreid commented Mar 23, 2024 • edited

compiler-errors commented Mar 23, 2024 • edited

compiler-errors commented Mar 23, 2024

kpreid commented Mar 23, 2024

This comment has been minimized.

kpreid commented Mar 23, 2024

compiler-errors commented Mar 23, 2024

bors commented Mar 23, 2024

kpreid commented Mar 23, 2024

compiler-errors commented Mar 23, 2024

bors commented Mar 23, 2024

matthiaskrgr commented Mar 25, 2024

kpreid commented Mar 25, 2024

Nilstrieb commented Mar 25, 2024

bors commented Mar 25, 2024

scottmcm Mar 25, 2024

Choose a reason for hiding this comment

In `pretty_print_type()`, print `async fn` futures' paths instead of spans. #122923

In `pretty_print_type()`, print `async fn` futures' paths instead of spans. #122923

kpreid commented Mar 23, 2024 •

edited

kpreid commented Mar 23, 2024 •

edited

compiler-errors commented Mar 23, 2024 •

edited