Add enabled_bits to ProofConfig

[ilyalesokhin-starkware]

Store per-component enable bits directly in ProofConfig instead of deriving them from component disabled state. This supports dynamic component sets in the Cairo1 verifier. Disabled components are now filtered out before being passed to the verifier, and pad_disabled re-expands values for channel mixing to maintain Fiat-Shamir compatibility.

[cursor]

PR Summary

High Risk
High risk because it changes proof transcript mixing and component selection logic in the STARK/circuit verifier; any mismatch in enabled_bits handling or padding can invalidate proofs or enable malformed-proof acceptance.

Overview
Adds explicit per-component enabled_bits to ProofConfig and threads it through all config builders. Callers now pass enable flags into ProofConfig::from_statement/from_components, and Cairo privacy config builds both the filtered component map and the full enable-bit vector.

Stops representing disabled components as EmptyComponent and instead filters them out. Verification/circuit construction now builds component maps from enabled_bits, and Cairo proof preparation drops disabled components’ log-sizes/claimed-sums before proof_from_stark_proof.

Preserves Fiat–Shamir transcript compatibility via padding. The verifier pads component log sizes and claimed sums back to the full component layout for channel mixing, updates logup-sum validation accordingly, and adjusts example/prover tests and the simple_* fixtures to reflect filtered claims plus padded transcript inputs.

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[reviewable-StarkWare]

This change is 

[ilyalesokhin-starkware]

• Add enabled_bits to ProofConfig #453 👈 (View in Graphite)
• Refactor Statement to keep track of component names #455
• main

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[ilyalesokhin-starkware]

@ilyalesokhin-starkware made 1 comment.
Reviewable status: 0 of 16 files reviewed, 2 unresolved discussions (waiting on az-starkware, Gali-StarkWare, and leo-starkware).

[ilyalesokhin-starkware]

@ilyalesokhin-starkware resolved 1 discussion.
Reviewable status: 0 of 19 files reviewed, all discussions resolved (waiting on az-starkware, Gali-StarkWare, and leo-starkware).

[Gali-StarkWare]

@Gali-StarkWare partially reviewed 3 files.
Reviewable status: 3 of 19 files reviewed, 1 unresolved discussion (waiting on az-starkware, ilyalesokhin-starkware, and leo-starkware).

[Gali-StarkWare]

@Gali-StarkWare reviewed all commit messages.
Reviewable status: 3 of 19 files reviewed, 1 unresolved discussion (waiting on az-starkware, ilyalesokhin-starkware, and leo-starkware).

[Gali-StarkWare]

@Gali-StarkWare reviewed 1 file and made 2 comments.
Reviewable status: 4 of 19 files reviewed, 3 unresolved discussions (waiting on az-starkware, ilyalesokhin-starkware, and leo-starkware).

---

crates/cairo_air/src/privacy.rs line 23 at r3 (raw file):

    let preprocessed_trace_variant = PreProcessedTraceVariant::CanonicalSmall;
    let privacy_set = privacy_components();
    let all = all_components::<NoValue>();

Suggestion:

let all_components = all_components::<NoValue>();

---

crates/cairo_air/src/privacy.rs line 26 at r3 (raw file):

    let enabled_bits: Vec<bool> = all.keys().map(|name| privacy_set.contains(name)).collect();
    let components: IndexMap<&'static str, Box<dyn CircuitEval<NoValue>>> =
        all.into_iter().filter(|(name, _)| privacy_set.contains(name)).collect();

Repeated code, maybe create them in one go? Similar to before with unzip?

Code quote:

    let enabled_bits: Vec<bool> = all.keys().map(|name| privacy_set.contains(name)).collect();
    let components: IndexMap<&'static str, Box<dyn CircuitEval<NoValue>>> =
        all.into_iter().filter(|(name, _)| privacy_set.contains(name)).collect();

[Gali-StarkWare]

@Gali-StarkWare reviewed 1 file and made 1 comment.
Reviewable status: 5 of 19 files reviewed, 4 unresolved discussions (waiting on az-starkware, ilyalesokhin-starkware, and leo-starkware).

---

crates/cairo_air/src/statement.rs line 232 at r3 (raw file):

                // The component is not supported by the circuit - actual_uses must be 0.
                eq(context, actual_uses, context.zero());
                continue;

Why the added continue?

Code quote:

continue;

[ilyalesokhin-starkware]

crates/cairo_air/src/statement.rs line 232 at r3 (raw file):

Previously, Gali-StarkWare wrote…

Why the added continue?

No need to check:
actual_uses <= component_size
when actual_uses == 0.

[ilyalesokhin-starkware]

@ilyalesokhin-starkware made 2 comments.
Reviewable status: 4 of 19 files reviewed, 3 unresolved discussions (waiting on az-starkware, Gali-StarkWare, and leo-starkware).

---

crates/cairo_air/src/privacy.rs line 26 at r3 (raw file):

Previously, Gali-StarkWare wrote…

Repeated code, maybe create them in one go? Similar to before with unzip?

Done.

---

crates/cairo_air/src/privacy.rs line 23 at r3 (raw file):

    let preprocessed_trace_variant = PreProcessedTraceVariant::CanonicalSmall;
    let privacy_set = privacy_components();
    let all = all_components::<NoValue>();

Done.

[Gali-StarkWare]

@Gali-StarkWare reviewed 2 files and all commit messages, and resolved 3 discussions.
Reviewable status: 6 of 19 files reviewed, all discussions resolved (waiting on az-starkware and leo-starkware).

[Gali-StarkWare]

@Gali-StarkWare reviewed 5 files and made 2 comments.
Reviewable status: 11 of 19 files reviewed, 2 unresolved discussions (waiting on az-starkware, ilyalesokhin-starkware, and leo-starkware).

---

crates/cairo_air/src/test.rs line 61 at r4 (raw file):

    let components: indexmap::IndexMap<&'static str, Box<dyn CircuitEval<QM31>>> =
        zip_eq(all_components::<QM31>().into_iter(), &component_enable_bits)
            .filter_map(|((component_name, component), &enable_bit)| {

What does it filter here?

Code quote:

filter_map

---

crates/stark_verifier_examples/src/simple_air.rs line 250 at r4 (raw file):

    // Mix the component log sizes into the channel.
    // Component_3 is disabled, so it has trace size 0.
    prover_channel.mix_felts(&pack_component_log_sizes(&COMPONENT_LOG_SIZES));

Revert and use packed_component_log_sizes later

Code quote:

 prover_channel.mix_felts(&pack_component_log_sizes(&COMPONENT_LOG_SIZES));

[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

There are 2 total unresolved issues (including 1 from previous review).

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[ilyalesokhin-starkware]

crates/cairo_air/src/test.rs line 61 at r4 (raw file):

Previously, Gali-StarkWare wrote…

What does it filter here?

I'm removing disable components.

[ilyalesokhin-starkware]

crates/stark_verifier_examples/src/simple_air.rs line 250 at r4 (raw file):

Previously, Gali-StarkWare wrote…

Revert and use packed_component_log_sizes later

Done,
Note that I want to remove the zero padding, so there is no point in making the padding code cleared.

[ilyalesokhin-starkware]

@ilyalesokhin-starkware resolved 1 discussion.
Reviewable status: 9 of 19 files reviewed, 1 unresolved discussion (waiting on az-starkware, Gali-StarkWare, and leo-starkware).