flow-control: Add cache node optimization.

[liorgold2]

Stack:

• flow-control: Add numeric+tuple+bindings test. #8132
• flow-control: Support lowering of EqualsLiteral node. #8131
• flow-control: Add an if-based numeric match. #8130
• flow-control: FilteredPatterns: Replace empty() with default(). #8129
• flow-control: Support lowering of Deconstruct node. #8116
• flow-control: Add cache node optimization. #8115 ⬅

⚠️ Part of a stack created by spr. Do not merge manually using the UI - doing so may have unexpected results.

[reviewable-StarkWare]

This change is 

[orizi]

Reviewed 4 of 4 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @liorgold2)

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 12 at r1 (raw file):

/// identically.
pub struct Cache<Input> {
    cache: RefCell<UnorderedHashMap<Input, NodeId>>,

doc why refcell.

[liorgold2]

Reviewable status: 3 of 4 files reviewed, 1 unresolved discussion (waiting on @orizi)

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 12 at r1 (raw file):

Previously, orizi wrote…

doc why refcell.

Done.

[orizi]

Reviewed all commit messages.
Reviewable status: 3 of 4 files reviewed, 2 unresolved discussions (waiting on @liorgold2)

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 15 at r2 (raw file):

    //
    // The cache is wrapped in a `RefCell` to allow modifying it without holding a `&mut` to it
    // (which would complicate its usage).

Suggestion:

    /// A map from input to the cached result.
    ///
    /// The cache is wrapped in a `RefCell` to allow modifying it without holding a `&mut` to it
    /// (which would complicate its usage).

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 15 at r2 (raw file):

    //
    // The cache is wrapped in a `RefCell` to allow modifying it without holding a `&mut` to it
    // (which would complicate its usage).

this is pretty much the definition of a refcell - why is this specifically more difficult?
i now understand - it is since it is a cache - and not an explicitly built mapper - so you consider caching as a non-mutating action. (i think i'd rather see something similar to this line)

but couldn't you just make it a mut fn?
you have it as a local variable in both usecases.

Code quote:

    // The cache is wrapped in a `RefCell` to allow modifying it without holding a `&mut` to it
    // (which would complicate its usage).

[liorgold2]

Reviewable status: 1 of 4 files reviewed, 2 unresolved discussions (waiting on @orizi)

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 15 at r2 (raw file):

Previously, orizi wrote…

this is pretty much the definition of a refcell - why is this specifically more difficult?
i now understand - it is since it is a cache - and not an explicitly built mapper - so you consider caching as a non-mutating action. (i think i'd rather see something similar to this line)

but couldn't you just make it a mut fn?
you have it as a local variable in both usecases.

Nice, works :)

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crates/cairo-lang-lowering/src/lower/flow_control/create_graph/cache.rs line 15 at r2 (raw file):

    //
    // The cache is wrapped in a `RefCell` to allow modifying it without holding a `&mut` to it
    // (which would complicate its usage).

Done.

[orizi]

Reviewed 3 of 3 files at r3, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @liorgold2)