Automatic plaf instance - Issue #129

examples/fibo_with_padding.rs

@@ -217,7 +217,7 @@ fn main() {
     }
 
     // plaf boilerplate
-    use chiquito::plonkish::backend::plaf::chiquito2Plaf;
+    use chiquito::plonkish::backend::plaf::{chiquito2Plaf, PlafInstance};
     use polyexen::plaf::{backends::halo2::PlafH2Circuit, WitnessDisplayCSV};
 
     // get Chiquito ir
@@ -234,9 +234,8 @@ fn main() {
     // this is unnecessary because Chiquito has a halo2 backend already
     let plaf_circuit = PlafH2Circuit { plaf, wit };
 
-    let plaf_instance = vec![vec![34.field(), 7.field()]];
     // same as halo2 boilerplate above
-    let prover_plaf = MockProver::<Fr>::run(8, &plaf_circuit, plaf_instance).unwrap();
+    let prover_plaf = MockProver::<Fr>::run(8, &plaf_circuit, plaf_circuit.instance()).unwrap();
 
     let result_plaf = prover_plaf.verify_par();
 

examples/fibonacci.rs

@@ -130,7 +130,7 @@ fn main() {
     }
 
     // plaf boilerplate
-    use chiquito::plonkish::backend::plaf::chiquito2Plaf;
+    use chiquito::plonkish::backend::plaf::{chiquito2Plaf, PlafInstance};
     use polyexen::plaf::{backends::halo2::PlafH2Circuit, WitnessDisplayCSV};
 
     // get Chiquito ir
@@ -148,7 +148,7 @@ fn main() {
     let plaf_circuit = PlafH2Circuit { plaf, wit };
 
     // same as halo2 boilerplate above
-    let prover_plaf = MockProver::<Fr>::run(8, &plaf_circuit, Vec::new()).unwrap();
+    let prover_plaf = MockProver::<Fr>::run(8, &plaf_circuit, plaf_circuit.instance()).unwrap();
 
     let result_plaf = prover_plaf.verify_par();
 

src/plonkish/backend/plaf.rs

@@ -16,8 +16,8 @@ use num_bigint::BigUint;
 use polyexen::{
     expr::{get_field_p, Column as pColumn, ColumnKind, ColumnQuery, Expr as pExpr, PlonkVar},
     plaf::{
-        ColumnFixed, ColumnPublic, ColumnWitness, CopyC as pCopyC, Lookup as pLookup, Plaf,
-        Poly as pPoly, Witness as pWitness,
+        backends::halo2::PlafH2Circuit, ColumnFixed, ColumnPublic, ColumnWitness, CopyC as pCopyC,
+        Lookup as pLookup, Plaf, Poly as pPoly, Witness as pWitness,
     },
 };
 
@@ -324,3 +324,46 @@ impl ChiquitoPlafWitGen {
         }
     }
 }
+
+pub trait PlafInstance<F> {
+    fn instance(&self) -> Vec<Vec<F>>;
+}
+
+impl<F: PrimeField> PlafInstance<F> for PlafH2Circuit {
+    fn instance(&self) -> Vec<Vec<F>> {
+        if !self.plaf.columns.public.is_empty() {
+            let mut instance_with_offsets = Vec::new();
+            for copy in &self.plaf.copys {
+                let (left_col, right_col) = &copy.columns;
+
+                let (witness_col, offsets) = match (left_col.kind, right_col.kind) {
+                    (ColumnKind::Witness, ColumnKind::Public) => (left_col, copy.offsets.clone()),
+                    (ColumnKind::Public, ColumnKind::Witness) => (
+                        right_col,
+                        copy.offsets.iter().map(|(l, r)| (*r, *l)).collect(),
+                    ),
+                    _ => continue,
+                };
+
+                for (witness_offset, public_offset) in offsets {
+                    instance_with_offsets.push((
+                        self.wit.witness[witness_col.index][witness_offset]
+                            .as_ref()
+                            .unwrap()
+                            .to_u64_digits()[0],
+                        public_offset,
+                    ));
+                }
+            }
+            instance_with_offsets.sort_by_key(|&(_, offset)| offset);
+            let instance_values = instance_with_offsets
+                .iter()
+                .map(|&(val, _)| F::from(val))
+                .collect();
+
+            return vec![instance_values];
+        }
+
+        Vec::new()
+    }
+}