perf: optimize function_with_body_direct_function_with_body_callees

[mattvaux]

Summary

Optimizes function_with_body_direct_function_with_body_callees by replacing collect::<Maybe<Vec<Option<_>>>>()? + flatten() with direct iteration. Processes Maybe<Option<_>> in a single pass, collecting only Some values and avoiding an intermediate vector.

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Type of change

Please check one:

• Bug fix (fixes incorrect behavior)
• New feature
• Performance improvement
• Documentation change with concrete technical impact
• Style, wording, formatting, or typo-only change

⚠️ Note:
To keep maintainer workload sustainable, we generally do not accept PRs that
are only minor wording, grammar, formatting, or style changes.
Such PRs may be closed without detailed review.

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Why is this change needed?

The previous implementation created an intermediate Vec<Option<_>> with all values (including None), then filtered in a second pass. This caused unnecessary allocations and two passes over the data.

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What was the behavior or documentation before?

Used collect::<Maybe<Vec<Option<_>>>>()? + flatten(), creating an intermediate vector and iterating twice.

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What is the behavior or documentation after?

Uses direct iteration in a single pass, collecting only Some values directly into the result set.

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Related issue or discussion (if any)

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Additional context

The same pattern exists in db.rs, but this PR addresses only the confirmed issue in cycles.rs. All tests pass (62 passed).

[reviewable-StarkWare]

This change is 

[orizi]

@orizi made 1 comment.
Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @mattvaux).

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crates/cairo-lang-lowering/src/graph_algorithms/cycles.rs line 46 at r1 (raw file):

 } } Ok(result)

Suggestion:

 db.function_with_body_direct_callees(function_id, dependency_type)? .into_iter() .filter_map(|function_id| { Some(function_id.body(db).transpose()?.map(|id| match id.generic_or_specialized(db) { GenericOrSpecialized::Generic(id) => id, GenericOrSpecialized::Specialized(_) => { unreachable!("Specialization of functions only occurs post concretization.") } })) }) .collect()

[mattvaux]

Fixed it

[orizi]

@orizi made 1 comment.
Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @mattvaux).

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crates/cairo-lang-lowering/src/graph_algorithms/cycles.rs line 46 at r1 (raw file):

 } } Ok(result)

i removed the extra collect - but you added it back.