test: add integration tests for constants codegen

air-script/tests/constants/constants.air

@@ -0,0 +1,26 @@
+def PubInputsAir
+
+constants:
+    A: 1
+    B: [0, 1]
+    C: [[1, 2], [2, 0]]
+
+trace_columns:
+    main: [a, b, c, d]
+
+public_inputs:
+    program_hash: [4]
+    stack_inputs: [4]
+    stack_outputs: [20]
+    overflow_addrs: [4]
+
+boundary_constraints:
+    enf a.first = A
+    enf b.first = A + B[0] * C[0][1]
+    enf c.first = (B[0] - C[1][1]) * A
+    enf d.first = A + B[0] - B[1] + C[0][0] - C[0][1] + C[1][0] - C[1][1]
+
+transition_constraints:
+    enf a' = a + A
+    enf b' = B[0] * b
+    enf c' = (C[0][0] + B[0]) * c

air-script/tests/constants/constants.rs

@@ -0,0 +1,104 @@
+use winter_air::{Air, AirContext, Assertion, AuxTraceRandElements, EvaluationFrame, ProofOptions as WinterProofOptions, TransitionConstraintDegree, TraceInfo};
+use winter_math::{fields, ExtensionOf, FieldElement};
+use winter_utils::{collections, ByteWriter, Serializable};
+
+const A: u64 = 1;
+const B: Vec<u64> = vec![0, 1];
+const C: Vec<Vec<u64>> = vec![vec![1, 2], vec![2, 0]];
+
+pub struct PublicInputs {
+    program_hash: [Felt; 4],
+    stack_inputs: [Felt; 4],
+    stack_outputs: [Felt; 20],
+    overflow_addrs: [Felt; 4],
+}
+
+impl PublicInputs {
+    pub fn new(program_hash: [Felt; 4], stack_inputs: [Felt; 4], stack_outputs: [Felt; 20], overflow_addrs: [Felt; 4]) -> Self {
+        Self { program_hash, stack_inputs, stack_outputs, overflow_addrs }
+    }
+}
+
+impl Serializable for PublicInputs {
+    fn write_into<W: ByteWriter>(&self, target: &mut W) {
+        target.write(self.program_hash.as_slice());
+        target.write(self.stack_inputs.as_slice());
+        target.write(self.stack_outputs.as_slice());
+        target.write(self.overflow_addrs.as_slice());
+    }
+}
+
+pub struct PubInputsAir {
+    context: AirContext<Felt>,
+    program_hash: [Felt; 4],
+    stack_inputs: [Felt; 4],
+    stack_outputs: [Felt; 20],
+    overflow_addrs: [Felt; 4],
+}
+
+impl PubInputsAir {
+    pub fn last_step(&self) -> usize {
+        self.trace_length() - self.context().num_transition_exemptions()
+    }
+}
+
+impl Air for PubInputsAir {
+    type BaseField = Felt;
+    type PublicInputs = PublicInputs;
+
+    fn context(&self) -> &AirContext<Felt> {
+        &self.context
+    }
+
+    fn new(trace_info: TraceInfo, public_inputs: PublicInputs, options: WinterProofOptions) -> Self {
+        let main_degrees = vec![TransitionConstraintDegree::new(1), TransitionConstraintDegree::new(1), TransitionConstraintDegree::new(1)];
+        let aux_degrees = vec![];
+        let num_main_assertions = 4;
+        let num_aux_assertions = 0;
+
+        let context = AirContext::new_multi_segment(
+            trace_info,
+            main_degrees,
+            aux_degrees,
+            num_main_assertions,
+            num_aux_assertions,
+            options,
+        )
+        .set_num_transition_exemptions(2);
+        Self { context, program_hash: public_inputs.program_hash, stack_inputs: public_inputs.stack_inputs, stack_outputs: public_inputs.stack_outputs, overflow_addrs: public_inputs.overflow_addrs }
+    }
+
+    fn get_periodic_column_values(&self) -> Vec<Vec<Felt>> {
+        vec![]
+    }
+
+    fn get_assertions(&self) -> Vec<Assertion<Felt>> {
+        let mut result = Vec::new();
+        result.push(Assertion::single(0, 0, E::from(A)));
+        result.push(Assertion::single(1, 0, (E::from(A)) + ((E::from(B[0])) * (E::from(C[0][1])))));
+        result.push(Assertion::single(2, 0, ((E::from(B[0])) - (E::from(C[1][1]))) * (E::from(A))));
+        result.push(Assertion::single(3, 0, ((((((E::from(A)) + (E::from(B[0]))) - (E::from(B[1]))) + (E::from(C[0][0]))) - (E::from(C[0][1]))) + (E::from(C[1][0]))) - (E::from(C[1][1]))));
+        result
+    }
+
+    fn get_aux_assertions<E: FieldElement<BaseField = Felt>>(&self, aux_rand_elements: &AuxTraceRandElements<E>) -> Vec<Assertion<E>> {
+        let mut result = Vec::new();
+        result
+    }
+
+    fn evaluate_transition<E: FieldElement<BaseField = Felt>>(&self, frame: &EvaluationFrame<E>, periodic_values: &[E], result: &mut [E]) {
+        let current = frame.current();
+        let next = frame.next();
+        result[0] = next[0] - (current[0] + E::from(A));
+        result[1] = next[1] - ((E::from(B[0])) * (current[1]));
+        result[2] = next[2] - ((E::from(C[0][0]) + E::from(B[0])) * (current[2]));
+    }
+
+    fn evaluate_aux_transition<F, E>(&self, main_frame: &EvaluationFrame<F>, aux_frame: &EvaluationFrame<E>, _periodic_values: &[F], aux_rand_elements: &AuxTraceRandElements<E>, result: &mut [E])
+    where F: FieldElement<BaseField = Felt>,
+          E: FieldElement<BaseField = Felt> + ExtensionOf<F>,
+    {
+        let current = aux_frame.current();
+        let next = aux_frame.next();
+    }
+}

air-script/tests/main.rs

@@ -65,3 +65,13 @@ fn bitwise() {
     let expected = expect_file!["bitwise/bitwise.rs"];
     expected.assert_eq(&generated_air);
 }
+
+#[test]
+fn constants() {
+    let generated_air = Test::new("tests/constants/constants.air".to_string())
+        .transpile()
+        .unwrap();
+
+    let expected = expect_file!["constants/constants.rs"];
+    expected.assert_eq(&generated_air);
+}

codegen/winterfell/src/air/boundary_constraints.rs

@@ -106,15 +106,16 @@ impl Codegen for BoundaryExpr {
             // TODO: Check element type and cast accordingly.
             Self::Elem(ident) => format!("E::from({})", ident),
             Self::VectorAccess(vector_access) => {
-                // check if vector_access is not a public input
+                // check if vector_access is a public input
+                // TODO: figure out a better way to handle this lookup.
                 if ir
                     .public_inputs()
                     .iter()
-                    .all(|input| input.0 != vector_access.name())
+                    .any(|input| input.0 == vector_access.name())
                 {
-                    format!("E::from({}[{}])", vector_access.name(), vector_access.idx())
+                    format!("self.{}[{}]", vector_access.name(), vector_access.idx())   
                 } else {
-                    format!("self.{}[{}]", vector_access.name(), vector_access.idx())
+                    format!("E::from({}[{}])", vector_access.name(), vector_access.idx())
                 }
             }
             Self::MatrixAccess(matrix_access) => format!(

codegen/winterfell/src/air/mod.rs

@@ -22,7 +22,7 @@ use transition_constraints::{add_fn_evaluate_aux_transition, add_fn_evaluate_tra
 /// Updates the provided scope with a new Air struct and Winterfell Air trait implementation
 /// which are equivalent the provided AirIR.
 pub(super) fn add_air(scope: &mut Scope, ir: &AirIR) {
-    // add constant declarations
+    // add constant declarations. Check required to avoid adding extra line during codegen.
     if !ir.constants().is_empty() {
         add_constants(scope, ir);
     }

codegen/winterfell/src/air/transition_constraints.rs

@@ -86,8 +86,15 @@ impl Codegen for Operation {
         match self {
             Operation::Constant(ConstantValue::Inline(value)) => format!("E::from({}_u64)", value),
             Operation::Constant(ConstantValue::Scalar(ident)) => format!("E::from({})", ident),
-            Operation::Constant(ConstantValue::Vector(vector_access)) => format!("E::from({}[{}])", vector_access.name(), vector_access.idx()),
-            Operation::Constant(ConstantValue::Matrix(matrix_access)) => format!("E::from({}[{}][{}])", matrix_access.name(), matrix_access.row_idx(), matrix_access.col_idx()),
+            Operation::Constant(ConstantValue::Vector(vector_access)) => {
+                format!("E::from({}[{}])", vector_access.name(), vector_access.idx())
+            }
+            Operation::Constant(ConstantValue::Matrix(matrix_access)) => format!(
+                "E::from({}[{}][{}])",
+                matrix_access.name(),
+                matrix_access.row_idx(),
+                matrix_access.col_idx()
+            ),
             Operation::TraceElement(trace_access) => match trace_access.row_offset() {
                 0 => {
                     format!("current[{}]", trace_access.col_idx())

ir/src/lib.rs

@@ -1,6 +1,7 @@
-
+pub use parser::ast::{
+    self, boundary_constraints::BoundaryExpr, constants::Constant, Identifier, PublicInput,
+};
 use parser::ast::{BoundaryStmt, TransitionStmt};
-pub use parser::ast::{self, constants::Constant, boundary_constraints::BoundaryExpr, Identifier, PublicInput};
 use std::collections::BTreeMap;
 
 mod symbol_table;