rustc_metadata: Encode/decode some LazyArrays without an Option

[petrochenkov]

and a couple of related changes, see individual commits.

Addresses comments in #107166 (comment) and #107166 (comment), cc @cjgillot @oli-obk.

[rustbot]

r? @oli-obk

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[petrochenkov]

@bors try @rust-timer queue

[bors]

⌛ Trying commit f4e2b95 with merge 8d7ff5231e79dc945a8ff8a94dc7441ccd5e221d...

[bors]

☀️ Try build successful - checks-actions
Build commit: 8d7ff5231e79dc945a8ff8a94dc7441ccd5e221d (8d7ff5231e79dc945a8ff8a94dc7441ccd5e221d)

[rust-timer]

Finished benchmarking commit (8d7ff5231e79dc945a8ff8a94dc7441ccd5e221d): 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
Regressions ❌ (secondary)	0.7%	[0.7%, 0.8%]	3
Improvements ✅ (primary)	-0.4%	[-0.5%, -0.3%]	2
Improvements ✅ (secondary)	-0.9%	[-1.3%, -0.3%]	11
All ❌✅ (primary)	-0.4%	[-0.5%, -0.3%]	2

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)	-	-	0
Regressions ❌ (secondary)	4.2%	[2.0%, 6.4%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-1.1%	[-1.1%, -1.1%]	1
All ❌✅ (primary)	-	-	0

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)	-	-	0
Regressions ❌ (secondary)	7.1%	[3.4%, 8.7%]	8
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

[petrochenkov]

I didn't expect it to be a perf change, but at least it's not a regression.
The externs changes are spurious as usual, both regressions and improvements, others may be too.

[oli-obk]

@bors r+

[bors]

📌 Commit f4e2b95 has been approved by oli-obk

It is now in the queue for this repository.

[bors]

⌛ Testing commit f4e2b95 with merge 4271e39e92a62ad546f7539eb321c4b7f07b671e...

[bors]

💔 Test failed - checks-actions

[oli-obk]

@bors retry building LLVM: could not create temporary file whilst writing archive: no more archived files

[bors]

⌛ Testing commit f4e2b95 with merge 35d6d70...

[rust-log-analyzer]

The job i686-mingw-2 failed! Check out the build log: (web) (plain)

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

[2568/3021] Linking CXX static library lib\libLLVMAggressiveInstCombine.a
[2569/3021] Linking CXX static library lib\libLLVMInstrumentation.a
[2570/3021] Linking CXX static library lib\libLLVMLinker.a
FAILED: lib/libLLVMLinker.a 
cmd.exe /C "cd . && "C:\Program Files\CMake\bin\cmake.exe" -E rm -f lib\libLLVMLinker.a && D:\a\rust\rust\mingw32\bin\ar.exe qc lib\libLLVMLinker.a  lib/Linker/CMakeFiles/LLVMLinker.dir/IRMover.cpp.obj lib/Linker/CMakeFiles/LLVMLinker.dir/LinkModules.cpp.obj && D:\a\rust\rust\mingw32\bin\ranlib.exe lib\libLLVMLinker.a && cd ."
D:\a\rust\rust\mingw32\bin\ar.exe: could not create temporary file whilst writing archive: no more archived files
[2571/3021] Linking CXX static library lib\libLLVMObjCARCOpts.a
[2572/3021] Linking CXX static library lib\libLLVMInstCombine.a
[2573/3021] Building CXX object tools/lto/CMakeFiles/LTO.dir/lto.cpp.obj
[2574/3021] Linking CXX static library lib\libLLVMVectorize.a
[2574/3021] Linking CXX static library lib\libLLVMVectorize.a
[2575/3021] Linking CXX executable bin\yaml-bench.exe
[2576/3021] Linking CXX executable bin\UnicodeNameMappingGenerator.exe
[2577/3021] Linking CXX executable bin\not.exe
ninja: build stopped: subcommand failed.
command did not execute successfully, got: exit code: 1


build script failed, must exit now', C:\Users\runneradmin\.cargo\registry\src\index.crates.io-1cd66030c949c28d\cmake-0.1.48\src\lib.rs:975:5
 finished in 381.544 seconds
Build completed successfully in 0:08:27
Build completed successfully in 0:08:27
make: *** [Makefile:80: ci-mingw-subset-2] Error 1

[bors]

☀️ Test successful - checks-actions
Approved by: oli-obk
Pushing 35d6d70 to master...

[rust-timer]

Finished benchmarking commit (35d6d70): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -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
Regressions ❌ (secondary)	2.7%	[1.4%, 3.9%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Max RSS (memory usage)

This benchmark run did not return any relevant results for this metric.

Cycles

This benchmark run did not return any relevant results for this metric.