mem squish

[ohad-starkware]

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[ohad-starkware]

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• mem squish #241 👈 (View in Graphite)
• fmt for cairo #237
• main

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[shaharsamocha7]

Reviewed 1 of 4 files at r1, all commit messages.
Reviewable status: 1 of 4 files reviewed, 2 unresolved discussions (waiting on @ohad-starkware)

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stwo_cairo_prover/crates/prover/src/components/memory/memory_address_to_id/component.rs line 19 at r1 (raw file):

// during The merkle commitment and FRI, as this component is usually the tallest in the Cairo AIR.
// TODO(Ohad): Change split to 8 after seq is implemented. NOTE: it is possible to split further
// with an expansion trick similar to the one used in XOR. Investigate if it is worth it.

I don't like those changes as we probably need to change everything here again.
I think the correct approach is to use the EXPAND_BITS as we have in XOR.

Code quote:

// TODO(Ohad): Change split to 8 after seq is implemented. NOTE: it is possible to split further
// with an expansion trick similar to the one used in XOR. Investigate if it is worth it.

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stwo_cairo_prover/out.txt line 1 at r1 (raw file):

Cool file but we don't need it in git :)

[shaharsamocha7]

Reviewable status: 1 of 4 files reviewed, 4 unresolved discussions (waiting on @ohad-starkware)

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stwo_cairo_prover/crates/prover/src/components/memory/memory_address_to_id/prover.rs line 83 at r1 (raw file):

        let next_multiple_of_16 = ((self.ids.len() + 15) >> 4) << 4;
        self.ids.resize(next_multiple_of_16, 0);
        self.multiplicities.resize(next_multiple_of_16, 0);

can we replace this by asserting that ids.len() >= 256?

Code quote:

        // Pad to a multiple of `N_LANES`.
        let next_multiple_of_16 = ((self.ids.len() + 15) >> 4) << 4;
        self.ids.resize(next_multiple_of_16, 0);
        self.multiplicities.resize(next_multiple_of_16, 0);

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stwo_cairo_prover/crates/prover/src/components/memory/memory_address_to_id/component.rs line 59 at r1 (raw file):

    fn evaluate<E: EvalAtRow>(&self, mut eval: E) -> E {
        let address = eval.next_trace_mask();
        for i in 0..SPLIT_SIZE {

I think SPLIT_SIZE should be generic

Code quote:

for i in 0..SPLIT_SIZE {