Move ty::print methods to Drop-based scope guards

[Mark-Simulacrum]

Primary goal is reducing codegen of the TLS access for each closure, which shaves ~3 seconds of bootstrap time over rustc as a whole.

[Mark-Simulacrum]

cc @antoyo and @bjorn3 on the codegen_gcc/cranelift changes (highfive didn't poke because I r'd ghost initially)

@bors try @rust-timer queue after moving to a macro -- shouldn't really matter for codegen perf, though.

r? rust-lang/compiler

Overall the perf improvement for bootstrap time here is pretty significant -- 3 seconds is a good chunk. The regression is IMO not significant enough (and pretty likely to be just optimizer noise) to block this PR from moving ahead.

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit 9763486 with merge 9052094ca5c51a6d68127658c18be082df1893b9...

[bors]

☀️ Try build successful - checks-actions
Build commit: 9052094ca5c51a6d68127658c18be082df1893b9 (9052094ca5c51a6d68127658c18be082df1893b9)

[rust-timer]

Queued 9052094ca5c51a6d68127658c18be082df1893b9 with parent 75d9a0a, future comparison URL.

[rust-timer]

Finished benchmarking commit (9052094ca5c51a6d68127658c18be082df1893b9): comparison url.

Summary: This benchmark run shows 13 relevant improvements 🎉 but 9 relevant regressions 😿 to instruction counts.

• Average relevant regression: 0.8%
• Average relevant improvement: -1.2%
• Largest improvement in instruction counts: -1.7% on full builds of match-stress-enum check
• Largest regression in instruction counts: 1.0% on full builds of inflate check

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

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 led 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-review -S-waiting-on-perf +perf-regression

[oli-obk]

@bors r+

How did you find this? Did it show up in cachegrind dumps?

[bors]

📌 Commit 9763486 has been approved by oli-obk

[Mark-Simulacrum]

No, cachegrind isn't really the right tool for tracing back to source code from LLVM IR. I'm looking at no-prepopulate-passes LLVM IR from rustc_query_impl and trying to identify duplicated work based on that (e.g., places where we're generating a lot of IR for no good reason).

[antoyo]

The gcc part looks good to me.

[bors]

⌛ Testing commit 9763486 with merge 523a1b1...

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 523a1b1 to master...

[rust-timer]

Finished benchmarking commit (523a1b1): comparison url.

Summary: This benchmark run did not return any relevant results.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression