Experiments on witness generator

Cargo.toml

@@ -49,7 +49,7 @@ tracing = "0.1.41"
 tracing-subscriber = { version = "0.3.18", features = ["env-filter", "ansi"] }
 base64 = "0.22.1"
 ruint = { version = "1.12.3", features = ["num-traits", "rand"] }
-rand = "0.8.5"
+rand = "0.9.0"
 subtle = "2.6.1"
 bytemuck = "1.19.0"
 hex-literal = "0.4.1"

merkle-hash-bench/Cargo.toml

@@ -67,7 +67,7 @@ icicle-bn254 = { git = "https://github.com/ingonyama-zk/icicle.git", branch = "m
 icicle-m31 = { git = "https://github.com/ingonyama-zk/icicle.git", branch = "main", optional = true }
 
 # ZKHash
-zkhash = { git = "https://extgit.isec.tugraz.at/krypto/zkfriendlyhashzoo.git", commit = "f252d2b2767bc88659615601ac13e19f52c2c11f", optional = true }
+zkhash = { git = "https://extgit.isec.tugraz.at/krypto/zkfriendlyhashzoo.git", rev = "f252d2b2767bc88659615601ac13e19f52c2c11f", optional = true }
 
 # Stwo
 stwo-prover = { git = "https://github.com/starkware-libs/stwo.git", version = "0.1.1", optional = true }

noir-r1cs/src/main.rs

@@ -1,5 +1,6 @@
 #![doc = include_str!("../README.md")]
 mod compiler;
+mod r1cs_emitter;
 mod sparse_matrix;
 mod utils;
 
@@ -119,6 +120,7 @@ fn noir(args: NoirCmd) -> AnyResult<()> {
     witness[2] = Some(FieldElement::from(5678_u32)); // b
 
     // Solve constraints (this is how Noir expects it to be done, judging from ACVM)
+    info!("Solving for witness.");
     for row in 0..r1cs.constraints {
         let [a, b, c] =
             [&r1cs.a, &r1cs.b, &r1cs.c].map(|mat| sparse_dot(mat.iter_row(row), &witness));
@@ -135,9 +137,10 @@ fn noir(args: NoirCmd) -> AnyResult<()> {
         let Some((col, val)) = solve_dot(mat.iter_row(row), &witness, val) else {
             panic!("Could not solve constraint {row}.")
         };
-        eprintln!("Constraint {row}: Solved for witness[{col}] = {val}");
+        // eprintln!("Constraint {row}: Solved for witness[{col}] = {val}");
         witness[col] = Some(val);
     }
+    info!("Witness found.");
 
     // Complete witness with entropy.
     // TODO: Use better entropy source and proper sampling.
@@ -147,7 +150,7 @@ fn noir(args: NoirCmd) -> AnyResult<()> {
         .map(|f| f.unwrap_or_else(|| FieldElement::from(rng.random::<u128>())))
         .collect::<Vec<_>>();
 
-    dbg!(&witness);
+    // dbg!(&witness);
 
     // Verify
     let a = mat_mul(&r1cs.a, &witness);
@@ -160,6 +163,7 @@ fn noir(args: NoirCmd) -> AnyResult<()> {
         .for_each(|(row, ((&a, &b), &c))| {
             assert_eq!(a * b, c, "Constraint {row} failed");
         });
+    info!("Witness verified.");
 
     // dbg!(&a);
     // dbg!(&b);

noir-r1cs/src/compiler.rs → noir-r1cs/src/r1cs/acir_source.rs

@@ -1,5 +1,5 @@
 use {
-    crate::SparseMatrix,
+    super::ConstraintSink,
     acir::{
         circuit::{Circuit, Opcode},
         native_types::{Expression, Witness},
@@ -8,30 +8,24 @@ use {
     std::collections::BTreeMap,
 };
 
-/// Represents a R1CS constraint system.
+/// Represents a R1CS constraint source from ACIR.
 #[derive(Debug, Clone)]
-pub struct R1CS {
-    pub a: SparseMatrix<FieldElement>,
-    pub b: SparseMatrix<FieldElement>,
-    pub c: SparseMatrix<FieldElement>,
-
-    // Remapping of witness indices to the r1cs_witness array
-    pub witnesses: usize,
-    pub remap:     BTreeMap<usize, usize>,
-
-    pub constraints: usize,
+pub struct AcirSource<'a> {
+    circuit:     &'a Circuit<FieldElement>,
+    witnesses:   usize,
+    constraints: usize,
+    witness_map: Vec<usize>,
 }
 
-impl R1CS {
-    pub fn new() -> Self {
-        Self {
-            a:           SparseMatrix::new(0, 1, FieldElement::zero()),
-            b:           SparseMatrix::new(0, 1, FieldElement::zero()),
-            c:           SparseMatrix::new(0, 1, FieldElement::zero()),
-            witnesses:   1,
-            remap:       BTreeMap::new(),
-            constraints: 0,
-        }
+impl<'a> AcirSource<'a> {
+    pub fn new(circuit: &'a Circuit<FieldElement>) -> Self {
+        let witness_map = vec![None; circuit.num_witnesses()];
+        // Do a preprocessing pass to compute the dimensions and witness map.
+        Self {}
+    }
+
+    pub fn emit(&self, sink: &mut impl ConstraintSink) {
+        todo!();
     }
 
     pub fn add_circuit(&mut self, circuit: &Circuit<FieldElement>) {

noir-r1cs/src/r1cs/matrix_sink.rs

@@ -0,0 +1,36 @@
+/// Represents a R1CS constraint system as Sparse Matrices.
+#[derive(Debug, Clone)]
+pub struct MatrixSink {
+    pub a: SparseMatrix<FieldElement>,
+    pub b: SparseMatrix<FieldElement>,
+    pub c: SparseMatrix<FieldElement>,
+}
+
+impl MatrixSink {
+    pub fn new(witnesses: usize, constraints: usize) -> Self {
+        Self {
+            a: SparseMatrix::new(constraints, witnesses, FieldElement::zero()),
+            b: SparseMatrix::new(constraints, witnesses, FieldElement::zero()),
+            c: SparseMatrix::new(constraints, witnesses, FieldElement::zero()),
+        }
+    }
+}
+
+impl ConstraintSink for MatrixSink {
+    fn add_constraint(
+        &mut self,
+        a: &[(FieldElement, usize)],
+        b: &[(FieldElement, usize)],
+        c: &[(FieldElement, usize)],
+    ) {
+        for (c, col) in a.iter().copied() {
+            self.a.set(row, col, c)
+        }
+        for (c, col) in b.iter().copied() {
+            self.b.set(row, col, c)
+        }
+        for (c, col) in c.iter().copied() {
+            self.c.set(row, col, c)
+        }
+    }
+}

noir-r1cs/src/r1cs/mod.rs

@@ -0,0 +1,9 @@
+pub trait ConstraintSink {
+    /// Add an R1CS constraint.
+    fn add_constraint(
+        &mut self,
+        a: &[(FieldElement, usize)],
+        b: &[(FieldElement, usize)],
+        c: &[(FieldElement, usize)],
+    );
+}