Update to LLVM 20.1.5

[dianqk]

@rustbot label A-LLVM T-compiler

[rustbot]

r? @cuviper

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[rustbot]

⚠️ Warning ⚠️

• Some commits in this PR modify submodules.

[cuviper]

@bors r+ rollup=never

[bors]

📌 Commit c7a2694 has been approved by cuviper

It is now in the queue for this repository.

[bors]

⌛ Testing commit c7a2694 with merge ae3b909...

[bors]

☀️ Test successful - checks-actions
Approved by: cuviper
Pushing ae3b909 to master...

[github-actions]

What is this?

This is an experimental post-merge analysis report that shows differences in test outcomes between the merged PR and its parent PR.

Comparing ac17c34 (parent) -> ae3b909 (this PR)

Test differences

Show 9 test diffs

Stage 2

• [assembly] tests/assembly/riscv-soft-abi-with-float-features.rs#LLVM-PRE-20: ignore (ignored when the LLVM version (20.1.4) is newer than majorversion 19) -> ignore (ignored when the LLVM version (20.1.5) is newer than majorversion 19) (J0)
• [assembly] tests/assembly/sanitizer/kcfi/emit-arity-indicator.rs#x86_64: ignore (ignored when the LLVM version 20.1.4 is older than 21.0.0) -> ignore (ignored when the LLVM version 20.1.5 is older than 21.0.0) (J0)
• [assembly] tests/assembly/x86_64-bigint-helpers.rs#llvm-pre-20: ignore (ignored when the LLVM version (20.1.4) is newer than majorversion 19) -> ignore (ignored when the LLVM version (20.1.5) is newer than majorversion 19) (J0)
• [codegen] tests/codegen/integer-cmp.rs#llvm-pre-20: ignore (ignored when the LLVM version (20.1.4) is newer than majorversion 19) -> ignore (ignored when the LLVM version (20.1.5) is newer than majorversion 19) (J0)
• [codegen] tests/codegen/issues/issue-101082.rs#x86-64-v3: ignore (ignored when the LLVM version 20.1.4 is older than 21.0.0) -> ignore (ignored when the LLVM version 20.1.5 is older than 21.0.0) (J0)
• [codegen] tests/codegen/sanitizer/kcfi/add-kcfi-arity-flag.rs#x86_64: ignore (ignored when the LLVM version 20.1.4 is older than 21.0.0) -> ignore (ignored when the LLVM version 20.1.5 is older than 21.0.0) (J0)
• [assembly] tests/assembly/x86_64-cmp.rs#LLVM-PRE-20-DEBUG: ignore (ignored when the LLVM version (20.1.4) is newer than majorversion 19) -> ignore (ignored when the LLVM version (20.1.5) is newer than majorversion 19) (J1)
• [assembly] tests/assembly/x86_64-cmp.rs#LLVM-PRE-20-OPTIM: ignore (ignored when the LLVM version (20.1.4) is newer than majorversion 19) -> ignore (ignored when the LLVM version (20.1.5) is newer than majorversion 19) (J1)
• [run-make] tests/run-make/compressed-debuginfo-zstd: pass -> ignore (ignored if LLVM wasn't build with zstd for ELF section compression (we want LLVM/LLD to be built with zstd support)) (J2)

Job group index

• J0: aarch64-apple, aarch64-gnu, arm-android, armhf-gnu, dist-i586-gnu-i586-i686-musl, i686-gnu-1, i686-gnu-nopt-1, i686-msvc-1, test-various, x86_64-apple-1, x86_64-gnu, x86_64-gnu-nopt, x86_64-gnu-stable, x86_64-mingw-1, x86_64-msvc-1
• J1: test-various, x86_64-apple-1, x86_64-gnu, x86_64-gnu-nopt, x86_64-gnu-stable, x86_64-mingw-1, x86_64-msvc-1
• J2: x86_64-gnu-nopt

Test dashboard

Run

cargo run --manifest-path src/ci/citool/Cargo.toml -- \
    test-dashboard ae3b909a323aa771db8ee3919c1454b77db05fbf --output-dir test-dashboard

And then open test-dashboard/index.html in your browser to see an overview of all executed tests.

Job duration changes

1. x86_64-rust-for-linux: 2553.7s -> 3986.9s (56.1%)
2. mingw-check: 1292.5s -> 1811.3s (40.1%)
3. armhf-gnu: 4454.1s -> 6148.3s (38.0%)
4. test-various: 4116.1s -> 5648.0s (37.2%)
5. arm-android: 5319.6s -> 7107.3s (33.6%)
6. x86_64-gnu-stable: 6521.3s -> 8702.2s (33.4%)
7. x86_64-gnu: 6344.3s -> 8363.9s (31.8%)
8. x86_64-apple-2: 6498.9s -> 4556.2s (-29.9%)
9. x86_64-gnu-aux: 6011.4s -> 7796.2s (29.7%)
10. x86_64-gnu-nopt: 5608.2s -> 7261.3s (29.5%)

How to interpret the job duration changes?

Job durations can vary a lot, based on the actual runner instance
that executed the job, system noise, invalidated caches, etc. The table above is provided
mostly for t-infra members, for simpler debugging of potential CI slow-downs.

[rust-timer]

Finished benchmarking commit (ae3b909): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -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
Regressions ❌ (secondary)	0.8%	[0.7%, 1.0%]	4
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

Results (primary 1.8%, secondary 1.0%)

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)	1.8%	[1.8%, 1.8%]	1
Regressions ❌ (secondary)	1.2%	[0.4%, 2.1%]	7
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.6%	[-0.6%, -0.6%]	1
All ❌✅ (primary)	1.8%	[1.8%, 1.8%]	1

Cycles

Results (secondary 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)	-	-	0
Regressions ❌ (secondary)	0.9%	[0.4%, 2.5%]	7
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-0.8%	[-1.0%, -0.4%]	4
All ❌✅ (primary)	-	-	0

Binary size

Results (secondary 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
Regressions ❌ (secondary)	0.1%	[0.1%, 0.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Bootstrap: 777.472s -> 777.393s (-0.01%)
Artifact size: 365.48 MiB -> 365.45 MiB (-0.01%)