Always preserve DebugInfo in DeadStoreElimination.

[cjgillot]

This is a version of #106852 that does not check the current crate's debuginfo flag, and always attempts to preserve debuginfo.

I haven't figured out how to handle mixing debuginfo levels for std, the one for the test, and the one for the CI target just right to merge #106852, so this can at least fix the debuginfo issue.

Fixes #103655

[rustbot]

r? @oli-obk

(rustbot has picked a reviewer for you, use r? to override)

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[rustbot]

Some changes occurred to MIR optimizations

cc @rust-lang/wg-mir-opt

[oli-obk]

@bors try @rust-timer queue

[bors]

⌛ Trying commit a93a9aa with merge a339f0b...

[bors]

☀️ Try build successful - checks-actions
Build commit: a339f0b (a339f0be6598c8f255ba92f0b9680937b36515fb)

[rust-timer]

Finished benchmarking commit (a339f0b): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

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 a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.8%	[0.2%, 2.3%]	19
Regressions ❌ (secondary)	1.3%	[0.2%, 2.3%]	6
Improvements ✅ (primary)	-0.4%	[-1.7%, -0.2%]	21
Improvements ✅ (secondary)	-0.4%	[-0.8%, -0.2%]	15
All ❌✅ (primary)	0.2%	[-1.7%, 2.3%]	40

Max RSS (memory usage)

Results

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)	3.1%	[0.3%, 5.2%]	7
Regressions ❌ (secondary)	3.6%	[3.6%, 3.6%]	1
Improvements ✅ (primary)	-4.9%	[-10.9%, -1.0%]	5
Improvements ✅ (secondary)	-3.4%	[-3.6%, -3.2%]	2
All ❌✅ (primary)	-0.2%	[-10.9%, 5.2%]	12

Cycles

Results

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%	[0.8%, 2.1%]	5
Regressions ❌ (secondary)	2.2%	[2.2%, 2.2%]	1
Improvements ✅ (primary)	-1.9%	[-1.9%, -1.9%]	1
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.8%	[-1.9%, 2.1%]	6

Binary size

Results

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)	0.4%	[0.0%, 2.1%]	99
Regressions ❌ (secondary)	0.7%	[0.0%, 2.5%]	28
Improvements ✅ (primary)	-1.1%	[-1.9%, -0.5%]	3
Improvements ✅ (secondary)	-0.2%	[-0.2%, -0.2%]	1
All ❌✅ (primary)	0.4%	[-1.9%, 2.1%]	102

Bootstrap: 629.749s -> 631.974s (0.35%)
Artifact size: 317.26 MiB -> 316.81 MiB (-0.14%)

[oli-obk]

It looks like the regressions are in codegen/llvm. Is that because there's now lots more debug info that needs to get processed (and/or dropped)?

[cjgillot]

I suppose yes. In the current situation, we end up with a lot of "dangling" debuginfo, that LLVM can optimize out easily. With this PR, LLVM needs to take care to preserve it, which takes time.

[oli-obk]

r=me (needs rebase)

[cjgillot]

@bors r=oli-obk

[bors]

📌 Commit b704697 has been approved by oli-obk

It is now in the queue for this repository.

[cjgillot]

Failure to build LLVM.
@bors retry

[bors]

⌛ Testing commit b704697 with merge aa680e4...

[rust-log-analyzer]

The job x86_64-apple-2 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

SCCACHE_BUCKET=rust-lang-ci-sccache2
SCRIPT=./x.py --stage 2 test tests/ui tests/rustdoc tests/run-make-fulldeps
SHELL=/bin/bash
SHLVL=3
SSH_AUTH_SOCK=/private/tmp/com.apple.launchd.dGm9EeZBMa/Listeners
STATS_EXTP=https://provjobdsettingscdn.blob.core.windows.net/settings/provjobdsettings-0.5.154/provjobd.data
STATS_RDCL=true
STATS_TIS=mining
STATS_TRP=true
---
---- [ui] tests/ui/panics/default-backtrace-ice.rs stdout ----
diff of stderr:

7 
8 aborting due to `-Z treat-err-as-bug=1`
- (end_short_backtrace)
11 (begin_short_backtrace)
12 (end_short_backtrace)
13 (begin_short_backtrace)
---
To only update this specific test, also pass `--test-args panics/default-backtrace-ice.rs`

error: 1 errors occurred comparing output.
status: exit status: 101
command: env -u RUST_BACKTRACE RUSTC_ICE="0" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2/bin/rustc" "/Users/runner/work/rust/rust/tests/ui/panics/default-backtrace-ice.rs" "-Zthreads=1" "-Zsimulate-remapped-rust-src-base=/rustc/FAKE_PREFIX" "-Ztranslate-remapped-path-to-local-path=no" "-Z" "ignore-directory-in-diagnostics-source-blocks=/Users/runner/.cargo" "--sysroot" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/stage2" "--target=x86_64-apple-darwin" "--error-format" "json" "--json" "future-incompat" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zwrite-long-types-to-disk=no" "-Cstrip=debuginfo" "--emit" "metadata" "-C" "prefer-dynamic" "--out-dir" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/ui/panics/default-backtrace-ice" "-A" "unused" "-A" "internal_features" "-Crpath" "-Cdebuginfo=0" "-Lnative=/Users/runner/work/rust/rust/build/x86_64-apple-darwin/native/rust-test-helpers" "-L" "/Users/runner/work/rust/rust/build/x86_64-apple-darwin/test/ui/panics/default-backtrace-ice/auxiliary" "-Z" "treat-err-as-bug=1"
--- stderr -------------------------------
error[E0425]: cannot find value `missing_ident` in this scope
##[error]  --> /Users/runner/work/rust/rust/tests/ui/panics/default-backtrace-ice.rs:21:13
   |
   |
LL | fn main() { missing_ident; }

thread 'rustc' panicked at compiler/rustc_errors/src/lib.rs:1729:30:
thread 'rustc' panicked at compiler/rustc_errors/src/lib.rs:1729:30:
aborting due to `-Z treat-err-as-bug=1`
   0:        0x10503f81b - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h470bb1637d2baa97
   1:        0x10509fee3 - core::fmt::write::h3b586c3e59416163
   2:        0x105034abe - std::io::Write::write_fmt::h03fd26c4033bf344
   3:        0x10503f5f9 - std::sys_common::backtrace::print::h7dab04d8ca17c05a
   3:        0x10503f5f9 - std::sys_common::backtrace::print::h7dab04d8ca17c05a
   4:        0x1050429f5 - std::panicking::default_hook::{{closure}}::h30a6789427e0c0d6
   5:        0x10504275c - std::panicking::default_hook::h25317be339ab623d
   6:        0x10d9e125b - <alloc[6d478a19f3173fdf]::boxed::Box<rustc_driver_impl[a6ce173b0ee1d304]::install_ice_hook::{closure#0}> as core[787b323d2fc9c5b0]::ops::function::Fn<(&dyn for<'a, 'b> core[787b323d2fc9c5b0]::ops::function::Fn<(&'a core[787b323d2fc9c5b0]::panic::panic_info::PanicInfo<'b>,), Output = ()> + core[787b323d2fc9c5b0]::marker::Send + core[787b323d2fc9c5b0]::marker::Sync, &core[787b323d2fc9c5b0]::panic::panic_info::PanicInfo)>>::call
   8:        0x105042e37 - std::panicking::begin_panic_handler::{{closure}}::h01deb1200b5a6e8b
   9:        0x10503fd29 - ___udivmodti4
  10:        0x105042bad - _rust_begin_unwind
  11:        0x1050cb225 - core::panicking::panic_fmt::h89fe924e330caa3b
  11:        0x1050cb225 - core::panicking::panic_fmt::h89fe924e330caa3b
  12:        0x1124e9d1f - <rustc_errors[877157530e93493]::HandlerInner>::panic_if_treat_err_as_bug
  13:        0x1124e9067 - <rustc_errors[877157530e93493]::HandlerInner>::emit_diagnostic::{closure#2}
  14:        0x10db514cf - rustc_interface[550d35f302029b0]::callbacks::track_diagnostic
  15:        0x1124e89ce - <rustc_errors[877157530e93493]::HandlerInner>::emit_diagnostic
  16:        0x11251f481 - <rustc_span[2041764bb9bd2549]::ErrorGuaranteed as rustc_errors[877157530e93493]::diagnostic_builder::EmissionGuarantee>::diagnostic_builder_emit_producing_guarantee
  17:        0x110e74ecd - <rustc_resolve[aa1ffa6c4ac0ab7c]::Resolver>::report_errors
  18:        0x110ef4eb3 - <rustc_session[6a123bff100ca7a4]::session::Session>::time::<(), <rustc_resolve[aa1ffa6c4ac0ab7c]::Resolver>::resolve_crate::{closure#0}>
  19:        0x110ea835e - <rustc_resolve[aa1ffa6c4ac0ab7c]::Resolver>::resolve_crate
  20:        0x10db57f95 - rustc_interface[550d35f302029b0]::passes::resolver_for_lowering
  21:        0x1114f8f3d - rustc_query_impl[13c67ac07ed4838c]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[13c67ac07ed4838c]::query_impl::resolver_for_lowering::dynamic_query::{closure#2}::{closure#0}, rustc_middle[2545d604a41fff53]::query::erase::Erased<[u8; 8usize]>>
  22:        0x111571a29 - <rustc_query_impl[13c67ac07ed4838c]::query_impl::resolver_for_lowering::dynamic_query::{closure#2} as core[787b323d2fc9c5b0]::ops::function::FnOnce<(rustc_middle[2545d604a41fff53]::ty::context::TyCtxt, ())>>::call_once
  23:        0x11144b67b - rustc_query_system[81f8ec8d0e38e3f8]::query::plumbing::try_execute_query::<rustc_query_impl[13c67ac07ed4838c]::DynamicConfig<rustc_query_system[81f8ec8d0e38e3f8]::query::caches::SingleCache<rustc_middle[2545d604a41fff53]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[13c67ac07ed4838c]::plumbing::QueryCtxt, false>
  24:        0x11153546a - rustc_query_impl[13c67ac07ed4838c]::query_impl::resolver_for_lowering::get_query_non_incr::__rust_end_short_backtrace
  25:        0x10d9a37f6 - <rustc_middle[2545d604a41fff53]::ty::context::GlobalCtxt>::enter::<rustc_driver_impl[a6ce173b0ee1d304]::run_compiler::{closure#1}::{closure#2}::{closure#4}, &rustc_data_structures[ca96739b41bd8e36]::steal::Steal<(rustc_middle[2545d604a41fff53]::ty::ResolverAstLowering, alloc[6d478a19f3173fdf]::rc::Rc<rustc_ast[cd24a5d63d20061d]::ast::Crate>)>>
  26:        0x10d9c39af - rustc_span[2041764bb9bd2549]::set_source_map::<core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>, rustc_interface[550d35f302029b0]::interface::run_compiler<core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>, rustc_driver_impl[a6ce173b0ee1d304]::run_compiler::{closure#1}>::{closure#0}::{closure#0}>
  27:        0x10d9ada4c - std[1240de32c44ecf53]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[550d35f302029b0]::util::run_in_thread_with_globals<rustc_interface[550d35f302029b0]::interface::run_compiler<core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>, rustc_driver_impl[a6ce173b0ee1d304]::run_compiler::{closure#1}>::{closure#0}, core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>>
  28:        0x10d9af1fe - <<std[1240de32c44ecf53]::thread::Builder>::spawn_unchecked_<rustc_interface[550d35f302029b0]::util::run_in_thread_with_globals<rustc_interface[550d35f302029b0]::interface::run_compiler<core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>, rustc_driver_impl[a6ce173b0ee1d304]::run_compiler::{closure#1}>::{closure#0}, core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[787b323d2fc9c5b0]::result::Result<(), rustc_span[2041764bb9bd2549]::ErrorGuaranteed>>::{closure#1} as core[787b323d2fc9c5b0]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  30:     0x7ff8186881d3 - __pthread_start

error: the compiler unexpectedly panicked. this is a bug.


note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.75.0-nightly (aa680e433 2023-10-07) running on x86_64-apple-darwin

note: compiler flags: -Z threads=1 -Z simulate-remapped-rust-src-base=/rustc/FAKE_PREFIX -Z translate-remapped-path-to-local-path=no -Z ignore-directory-in-diagnostics-source-blocks=/Users/runner/.cargo -C codegen-units=1 -Z ui-testing -Z deduplicate-diagnostics=no -Z write-long-types-to-disk=no -C strip=debuginfo -C prefer-dynamic -C rpath -C debuginfo=0 -Z treat-err-as-bug=1
query stack during panic:
#0 [resolver_for_lowering] getting the resolver for lowering
end of query stack
------------------------------------------

[bors]

💔 Test failed - checks-actions

[cjgillot]

Failure appears unrelated.
@bors retry

[bors]

⌛ Testing commit b704697 with merge 1e3c8f1...

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 1e3c8f1 to master...

[rust-timer]

Finished benchmarking commit (1e3c8f1): comparison URL.

Overall result: ❌✅ regressions and improvements - ACTION NEEDED

Next Steps: If you can justify the regressions found in this perf run, please indicate this with @rustbot label: +perf-regression-triaged along with sufficient written justification. If you cannot justify the regressions please open an issue or create a new PR that fixes the regressions, add a comment linking to the newly created issue or PR, and then add the perf-regression-triaged label to this PR.

@rustbot label: +perf-regression
cc @rust-lang/wg-compiler-performance

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.7%	[0.2%, 3.1%]	30
Regressions ❌ (secondary)	1.4%	[0.1%, 2.3%]	13
Improvements ✅ (primary)	-1.1%	[-3.1%, -0.2%]	4
Improvements ✅ (secondary)	-0.3%	[-0.3%, -0.3%]	1
All ❌✅ (primary)	0.5%	[-3.1%, 3.1%]	34

Max RSS (memory usage)

Results

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)	5.2%	[0.4%, 12.9%]	5
Regressions ❌ (secondary)	4.2%	[4.2%, 4.2%]	1
Improvements ✅ (primary)	-6.0%	[-8.0%, -4.0%]	2
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	2.0%	[-8.0%, 12.9%]	7

Cycles

Results

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)	1.2%	[0.7%, 3.3%]	10
Regressions ❌ (secondary)	7.3%	[1.6%, 9.0%]	7
Improvements ✅ (primary)	-1.7%	[-2.1%, -1.3%]	2
Improvements ✅ (secondary)	-1.7%	[-2.2%, -1.3%]	2
All ❌✅ (primary)	0.7%	[-2.1%, 3.3%]	12

Binary size

Results

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)	0.4%	[0.0%, 2.8%]	92
Regressions ❌ (secondary)	0.7%	[0.0%, 2.5%]	28
Improvements ✅ (primary)	-1.3%	[-2.3%, -0.7%]	3
Improvements ✅ (secondary)	-0.2%	[-0.2%, -0.2%]	1
All ❌✅ (primary)	0.3%	[-2.3%, 2.8%]	95

Bootstrap: 621.59s -> 625.98s (0.71%)
Artifact size: 270.70 MiB -> 270.83 MiB (0.05%)