chore(ssa): Do not run Brillig entry point analysis when no globals have been declared

[vezenovm]

Description

Problem*

No issue just something I noticed while looking at #8099.

We already skip Brillig entry point specialization if we have a single Brillig entry point (e.g. main is Brillig). We can also avoid specializing Brillig functions for programs that do not use globals at all.

Summary*

Check whether any globals have been declared. If not we can skip the Brillig entry point analysis.

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.

[TomAFrench]

We've got a panic in brillig_calls_array due to "f4 has multiple entry points"

[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: 86cad8b	Previous: 7d8b3bc	Ratio
test_report_AztecProtocol_aztec-packages_noir-projects_noir-protocol-circuits_crates_blob	49 s	40 s	1.23

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

CC: @TomAFrench

[github-actions]

⚠️ Performance Alert ⚠️

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

Benchmark suite	Current: be1bf92	Previous: 1df587d	Ratio
private-kernel-inner	270.8 MB	209.58 MB	1.29
private-kernel-reset	454.35 MB	246.67 MB	1.84
rollup-block-root	7780 MB	1710 MB	4.55
rollup-root	322.46 MB	261.28 MB	1.23

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

CC: @TomAFrench

[vezenovm]

We've got a panic in brillig_calls_array due to "f4 has multiple entry points"

Yeah, we then need to handle that we did not specialize entry points during Brillig globals code gen. We also hoist constants during the globals code gen so that complicates things a bit further as well. This is looking to be a bit more trouble than it is worth at the moment, so I am going to close.