fix: Add a remove_unreachable_instructions SSA pass (with unreachable terminator)

[asterite]

Description

Problem

Resolves #8774
Resolves #8994

Summary

Alternative to #8979 that introduces a new unreachable terminator.

Additional Context

Documentation

Check one:

• No documentation needed.
• Documentation included in this PR.
• [For Experimental Features] Documentation to be submitted in a separate PR.

PR Checklist

• I have tested the changes locally.
• I have formatted the changes with Prettier and/or cargo fmt on default settings.

[github-actions]

ACVM Benchmarks

Details

Benchmark suite	Current: 85a1c3c	Previous: c686a3e	Ratio
purely_sequential_opcodes	252152 ns/iter (± 1283)	254354 ns/iter (± 1083)	0.99
perfectly_parallel_opcodes	228388 ns/iter (± 863)	224528 ns/iter (± 3260)	1.02
perfectly_parallel_batch_inversion_opcodes	2784139 ns/iter (± 9094)	2777525 ns/iter (± 3133)	1.00

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[github-actions]

Execution Time

Details

Benchmark suite	Current: 85a1c3c	Previous: 759dc57	Ratio
private-kernel-inner	0.028 s	0.027 s	1.04
private-kernel-reset	0.162 s	0.161 s	1.01
private-kernel-tail	0.011 s	0.012 s	0.92
rollup-base-private	0.288 s	0.287 s	1.00
rollup-base-public	0.184 s	0.184 s	1
rollup-block-root	13 s	13.3 s	0.98
rollup-merge	0.004 s	0.003 s	1.33
rollup-root	0.005 s	0.005 s	1
semaphore-depth-10	0.02 s	0.023 s	0.87

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[github-actions]

Compilation Time

Details

Benchmark suite	Current: 85a1c3c	Previous: c686a3e	Ratio
private-kernel-inner	2.436 s	2.34 s	1.04
private-kernel-reset	7.4 s	7.396 s	1.00
private-kernel-tail	1.114 s	1.064 s	1.05
rollup-base-private	15.4 s	15.74 s	0.98
rollup-base-public	13.52 s	13.28 s	1.02
rollup-block-root-empty	18.54 s	18.42 s	1.01
rollup-block-root-single-tx	184 s	183 s	1.01
rollup-block-root	179 s	186 s	0.96
rollup-merge	1.276 s	1.166 s	1.09
rollup-root	1.332 s	1.364 s	0.98
semaphore-depth-10	0.778 s	0.801 s	0.97

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[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Compilation Time'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 1da08b5	Previous: f8c71c2	Ratio
rollup-base-private	18.8 s	15.56 s	1.21

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CC: @TomAFrench

[github-actions]

Artifact Size

Details

Benchmark suite	Current: 85a1c3c	Previous: 759dc57	Ratio
private-kernel-inner	1135.2 KB	1135.2 KB	1
private-kernel-reset	2072.4 KB	2072.4 KB	1
private-kernel-tail	589.1 KB	589.1 KB	1
rollup-base-private	4933.9 KB	4933.9 KB	1
rollup-base-public	3974.5 KB	3974.5 KB	1
rollup-block-root-empty	3876.9 KB	3876.9 KB	1
rollup-block-root-single-tx	32734 KB	32734 KB	1
rollup-block-root	32763.9 KB	32763.9 KB	1
rollup-merge	185.8 KB	185.8 KB	1
rollup-root	410.2 KB	410.2 KB	1
semaphore-depth-10	636.4 KB	636.4 KB	1

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[github-actions]

Test Suite Duration

Details

Benchmark suite	Current: 85a1c3c	Previous: 3838c69	Ratio
test_report_AztecProtocol_aztec-packages_noir-projects_aztec-nr	81 s	75 s	1.08
test_report_AztecProtocol_aztec-packages_noir-projects_noir-contracts	129 s	127 s	1.02
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_blob	180 s	141 s	1.28
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_private-kernel-lib	211 s	204 s	1.03
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_rollup-lib	558 s
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_types	75 s	73 s	1.03
test_report_noir-lang_noir-bignum_	373 s
test_report_noir-lang_noir_bigcurve_	269 s
test_report_noir-lang_sha512_	15 s	15 s	1
test_report_zkpassport_noir-ecdsa_	102 s	115 s	0.89
test_report_zkpassport_noir_rsa_	1 s	2 s	0.50

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[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Test Suite Duration'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 85a1c3c	Previous: 3838c69	Ratio
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_blob	180 s	141 s	1.28

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench

[github-actions]

Execution Memory

Details

Benchmark suite	Current: 85a1c3c	Previous: 759dc57	Ratio
private-kernel-inner	202.35 MB	202.35 MB	1
private-kernel-reset	226.1 MB	226.1 MB	1
private-kernel-tail	177.64 MB	177.64 MB	1
rollup-base-private	507.42 MB	507.42 MB	1
rollup-base-public	440.61 MB	440.61 MB	1
rollup-block-root	1510 MB	1510 MB	1
rollup-merge	329.7 MB	329.7 MB	1
rollup-root	331.8 MB	331.8 MB	1
semaphore_depth_10	71.01 MB	71.01 MB	1

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Compilation Memory

Details

Benchmark suite	Current: 85a1c3c	Previous: 759dc57	Ratio
private-kernel-inner	293.28 MB	293.31 MB	1.00
private-kernel-reset	533.88 MB	534.34 MB	1.00
private-kernel-tail	191.87 MB	191.87 MB	1
rollup-base-private	1400 MB	1400 MB	1
rollup-base-public	1530 MB	1530 MB	1
rollup-block-root-empty	1090 MB	1090 MB	1
rollup-block-root-single-tx	9410 MB	9410 MB	1
rollup-block-root	9420 MB	9420 MB	1
rollup-merge	344.77 MB	344.76 MB	1.00
rollup-root	354.78 MB	354.76 MB	1.00
semaphore_depth_10	106.38 MB	106.44 MB	1.00

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[TomAFrench]

The only issue with this new terminator is that it currently isn't implemented in the inlining pass. However, the pass that introduces unreachable terminators currently runs way after inlining so it's not an issue.

I don't think this is a showstopper. We've got a number of other passes which are required to run before or after another pass so this wouldn't be unique.

[jfecher]

LGTM. I think I prefer this approach to the old one. It makes it easier to track what happened previously and I like that it models our intention of the code more closely.

I agree with Tom that the ordering constraint on this pass is not the end of the world.

[github-actions]

⚠️ Performance Alert ⚠️

Possible performance regression was detected for benchmark 'Execution Time'.
Benchmark result of this commit is worse than the previous benchmark result exceeding threshold 1.20.

Benchmark suite	Current: 85a1c3c	Previous: 759dc57	Ratio
rollup-merge	0.004 s	0.003 s	1.33

This comment was automatically generated by workflow using github-action-benchmark.

CC: @TomAFrench