Implement GkrOps for SIMD backend

[andrewmilson]

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[andrewmilson]

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• Add benchmarks for GKR lookups #673
• Implement LogupOps for SIMD backend #641
• Implement GrandProductOps for SIMD backend #640
• Implement GkrOps for SIMD backend #630 👈
• Implement MleOps for SIMD backend #629
• Add GKR implementation of Logup lookups #623
• Add GKR implementation of Grand Product lookups #620
• Implement GkrOps for CPU backend #621
• Add batch GKR prover and verifier #581
• Rename CPU* structs to Cpu* to conform to Rust's naming convention #617
• Remove AVX backend #616
• Convert wide_fibbonacci AVX backend example to SIMD backend #615
• Update CI to test Wasm simd128, avx2 and aarch64 neon #614
• Fix CirclePointIndex bug in debug mode for 32-bit archs #613
• Change opt-level in benchmarks script #612
• Add benchmarks for SIMD m31 #611
• Add benchmarks for SIMD merkle #610
• dev

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[spapinistarkware]

Reviewed 3 of 6 files at r1, 3 of 3 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @andrewmilson)

[shaharsamocha7]

Reviewed 2 of 6 files at r1, 2 of 2 files at r3, all commit messages.
Reviewable status: all files reviewed, 3 unresolved discussions (waiting on @andrewmilson)

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 21 at r3 (raw file):

        }

        // Start DP with CPU backend to prevent dealing with instances smaller than a SIMD vector.

what's DP?

Code quote:

Start DP with

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 22 at r3 (raw file):

        // Start DP with CPU backend to prevent dealing with instances smaller than a SIMD vector.
        let (y_initial, y_rem) = y.split_last_chunk::<{ LOG_N_LANES as usize }>().unwrap();

y_initial is the last 4 elements in the vector, need another name IMO
or maybe comment that we pass on y in reverse order?

Code quote:

let (y_initial, y_rem) = y.split_last_chunk::<{ LOG_N_LANES as usize }>().unwrap();

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 70 at r3 (raw file):

    #[test]
    fn gen_eq_evals_matches_cpu() {

Can you also add a test where y.len() < LOG_N_LANES?

Code quote:

fn gen_eq_evals_matches_cpu() {

[andrewmilson]

Reviewable status: 5 of 6 files reviewed, 3 unresolved discussions (waiting on @shaharsamocha7 and @spapinistarkware)

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 21 at r3 (raw file):

Previously, shaharsamocha7 wrote…

what's DP?

Dynamic Programming

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 22 at r3 (raw file):

Previously, shaharsamocha7 wrote…

y_initial is the last 4 elements in the vector, need another name IMO
or maybe comment that we pass on y in reverse order?

Initial in the sense that it's the y values that create the initial values for the algorithm but I see how It's confusing. Changed to y_last_chunk. WDYT?

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crates/prover/src/core/backend/simd/lookups/gkr.rs line 70 at r3 (raw file):

Previously, shaharsamocha7 wrote…

Can you also add a test where y.len() < LOG_N_LANES?

Added