chore: remove noirc_abi dependency from noirc_evaluator (#3492)

compiler/noirc_driver/src/abi_gen.rs

@@ -0,0 +1,141 @@
+use std::collections::BTreeMap;
+
+use acvm::acir::native_types::Witness;
+use iter_extended::{btree_map, vecmap};
+use noirc_abi::{Abi, AbiParameter, AbiType};
+use noirc_frontend::{
+    hir::Context,
+    hir_def::{function::Param, stmt::HirPattern},
+    node_interner::{FuncId, NodeInterner},
+};
+use std::ops::Range;
+
+/// Arranges a function signature and a generated circuit's return witnesses into a
+/// `noirc_abi::Abi`.
+pub(super) fn gen_abi(
+    context: &Context,
+    func_id: &FuncId,
+    input_witnesses: Vec<Witness>,
+    return_witnesses: Vec<Witness>,
+) -> Abi {
+    let (parameters, return_type) = compute_function_abi(context, func_id);
+    let param_witnesses = param_witnesses_from_abi_param(&parameters, input_witnesses);
+    Abi { parameters, return_type, param_witnesses, return_witnesses }
+}
+
+pub(super) fn compute_function_abi(
+    context: &Context,
+    func_id: &FuncId,
+) -> (Vec<AbiParameter>, Option<AbiType>) {
+    let func_meta = context.def_interner.function_meta(func_id);
+
+    let (parameters, return_type) = func_meta.into_function_signature();
+    let parameters = into_abi_params(context, parameters);
+    let return_type = return_type.map(|typ| AbiType::from_type(context, &typ));
+    (parameters, return_type)
+}
+
+/// Attempts to retrieve the name of this parameter. Returns None
+/// if this parameter is a tuple or struct pattern.
+fn get_param_name<'a>(pattern: &HirPattern, interner: &'a NodeInterner) -> Option<&'a str> {
+    match pattern {
+        HirPattern::Identifier(ident) => Some(interner.definition_name(ident.id)),
+        HirPattern::Mutable(pattern, _) => get_param_name(pattern, interner),
+        HirPattern::Tuple(_, _) => None,
+        HirPattern::Struct(_, _, _) => None,
+    }
+}
+
+fn into_abi_params(context: &Context, params: Vec<Param>) -> Vec<AbiParameter> {
+    vecmap(params, |(pattern, typ, vis)| {
+        let param_name = get_param_name(&pattern, &context.def_interner)
+            .expect("Abi for tuple and struct parameters is unimplemented")
+            .to_owned();
+        let as_abi = AbiType::from_type(context, &typ);
+        AbiParameter { name: param_name, typ: as_abi, visibility: vis.into() }
+    })
+}
+
+// Takes each abi parameter and shallowly maps to the expected witness range in which the
+// parameter's constituent values live.
+fn param_witnesses_from_abi_param(
+    abi_params: &Vec<AbiParameter>,
+    input_witnesses: Vec<Witness>,
+) -> BTreeMap<String, Vec<Range<Witness>>> {
+    let mut idx = 0_usize;
+    if input_witnesses.is_empty() {
+        return BTreeMap::new();
+    }
+
+    btree_map(abi_params, |param| {
+        let num_field_elements_needed = param.typ.field_count() as usize;
+        let param_witnesses = &input_witnesses[idx..idx + num_field_elements_needed];
+
+        // It's likely that `param_witnesses` will consist of mostly incrementing witness indices.
+        // We then want to collapse these into `Range`s to save space.
+        let param_witnesses = collapse_ranges(param_witnesses);
+        idx += num_field_elements_needed;
+        (param.name.clone(), param_witnesses)
+    })
+}
+
+/// Takes a vector of [`Witnesses`][`Witness`] and collapses it into a vector of [`Range`]s of [`Witnesses`][`Witness`].
+fn collapse_ranges(witnesses: &[Witness]) -> Vec<Range<Witness>> {
+    if witnesses.is_empty() {
+        return Vec::new();
+    }
+    let mut wit = Vec::new();
+    let mut last_wit: Witness = witnesses[0];
+
+    for (i, witness) in witnesses.iter().enumerate() {
+        if i == 0 {
+            continue;
+        };
+        let witness_index = witness.witness_index();
+        let prev_witness_index = witnesses[i - 1].witness_index();
+        if witness_index != prev_witness_index + 1 {
+            wit.push(last_wit..Witness(prev_witness_index + 1));
+            last_wit = *witness;
+        };
+    }
+
+    let last_witness = witnesses.last().unwrap().witness_index();
+    wit.push(last_wit..Witness(last_witness + 1));
+
+    wit
+}
+
+#[cfg(test)]
+mod test {
+    use std::ops::Range;
+
+    use acvm::acir::native_types::Witness;
+
+    use super::collapse_ranges;
+
+    #[test]
+    fn collapses_single_range() {
+        let witnesses: Vec<_> = vec![1, 2, 3].into_iter().map(Witness::from).collect();
+
+        let collapsed_witnesses = collapse_ranges(&witnesses);
+
+        assert_eq!(collapsed_witnesses, vec![Range { start: Witness(1), end: Witness(4) },])
+    }
+
+    #[test]
+    fn collapse_ranges_correctly() {
+        let witnesses: Vec<_> =
+            vec![1, 2, 3, 5, 6, 2, 3, 4].into_iter().map(Witness::from).collect();
+
+        let collapsed_witnesses = collapse_ranges(&witnesses);
+
+        assert_eq!(
+            collapsed_witnesses,
+            vec![
+                Range { start: Witness(1), end: Witness(4) },
+                Range { start: Witness(5), end: Witness(7) },
+                Range { start: Witness(2), end: Witness(5) }
+            ]
+        )
+    }
+}

compiler/noirc_driver/src/lib.rs

@@ -8,8 +8,8 @@ use fm::FileId;
 use iter_extended::vecmap;
 use noirc_abi::{AbiParameter, AbiType, ContractEvent};
 use noirc_errors::{CustomDiagnostic, FileDiagnostic};
+use noirc_evaluator::create_circuit;
 use noirc_evaluator::errors::RuntimeError;
-use noirc_evaluator::{create_circuit, into_abi_params};
 use noirc_frontend::graph::{CrateId, CrateName};
 use noirc_frontend::hir::def_map::{Contract, CrateDefMap};
 use noirc_frontend::hir::Context;
@@ -18,6 +18,7 @@ use noirc_frontend::node_interner::FuncId;
 use serde::{Deserialize, Serialize};
 use std::path::Path;
 
+mod abi_gen;
 mod contract;
 mod debug;
 mod program;
@@ -140,12 +141,7 @@ pub fn compute_function_abi(
 ) -> Option<(Vec<AbiParameter>, Option<AbiType>)> {
     let main_function = context.get_main_function(crate_id)?;
 
-    let func_meta = context.def_interner.function_meta(&main_function);
-
-    let (parameters, return_type) = func_meta.into_function_signature();
-    let parameters = into_abi_params(context, parameters);
-    let return_type = return_type.map(|typ| AbiType::from_type(context, &typ));
-    Some((parameters, return_type))
+    Some(abi_gen::compute_function_abi(context, &main_function))
 }
 
 /// Run the frontend to check the crate for errors then compile the main function if there were none
@@ -345,9 +341,10 @@ pub fn compile_no_check(
         return Ok(cached_program.expect("cache must exist for hashes to match"));
     }
 
-    let (circuit, debug, abi, warnings) =
-        create_circuit(context, program, options.show_ssa, options.show_brillig)?;
+    let (circuit, debug, input_witnesses, return_witnesses, warnings) =
+        create_circuit(program, options.show_ssa, options.show_brillig)?;
 
+    let abi = abi_gen::gen_abi(context, &main_function, input_witnesses, return_witnesses);
     let file_map = filter_relevant_files(&[debug.clone()], &context.file_manager);
 
     Ok(CompiledProgram {

compiler/noirc_evaluator/Cargo.toml

@@ -10,7 +10,6 @@ license.workspace = true
 [dependencies]
 noirc_frontend.workspace = true
 noirc_errors.workspace = true
-noirc_abi.workspace = true
 acvm.workspace = true
 fxhash.workspace = true
 iter-extended.workspace = true

compiler/noirc_evaluator/src/lib.rs

@@ -11,5 +11,4 @@ pub mod ssa;
 
 pub mod brillig;
 
-pub use ssa::abi_gen::into_abi_params;
 pub use ssa::create_circuit;

compiler/noirc_evaluator/src/ssa.rs

@@ -7,10 +7,7 @@
 //! This module heavily borrows from Cranelift
 #![allow(dead_code)]
 
-use std::{
-    collections::{BTreeMap, BTreeSet},
-    ops::Range,
-};
+use std::collections::BTreeSet;
 
 use crate::{
     brillig::Brillig,
@@ -23,13 +20,12 @@ use acvm::acir::{
 
 use noirc_errors::debug_info::DebugInfo;
 
-use noirc_abi::Abi;
-
-use noirc_frontend::{hir::Context, monomorphization::ast::Program};
+use noirc_frontend::{
+    hir_def::function::FunctionSignature, monomorphization::ast::Program, Visibility,
+};
 
-use self::{abi_gen::gen_abi, acir_gen::GeneratedAcir, ssa_gen::Ssa};
+use self::{acir_gen::GeneratedAcir, ssa_gen::Ssa};
 
-pub mod abi_gen;
 mod acir_gen;
 pub(super) mod function_builder;
 pub mod ir;
@@ -81,12 +77,12 @@ pub(crate) fn optimize_into_acir(
 /// Compiles the [`Program`] into [`ACIR`][acvm::acir::circuit::Circuit].
 ///
 /// The output ACIR is is backend-agnostic and so must go through a transformation pass before usage in proof generation.
+#[allow(clippy::type_complexity)]
 pub fn create_circuit(
-    context: &Context,
     program: Program,
     enable_ssa_logging: bool,
     enable_brillig_logging: bool,
-) -> Result<(Circuit, DebugInfo, Abi, Vec<SsaReport>), RuntimeError> {
+) -> Result<(Circuit, DebugInfo, Vec<Witness>, Vec<Witness>, Vec<SsaReport>), RuntimeError> {
     let func_sig = program.main_function_signature.clone();
     let mut generated_acir =
         optimize_into_acir(program, enable_ssa_logging, enable_brillig_logging)?;
@@ -101,15 +97,11 @@ pub fn create_circuit(
         ..
     } = generated_acir;
 
-    let abi = gen_abi(context, func_sig, input_witnesses, return_witnesses.clone());
-    let public_abi = abi.clone().public_abi();
-
-    let public_parameters = PublicInputs(tree_to_set(&public_abi.param_witnesses));
+    let (public_parameter_witnesses, private_parameters) =
+        split_public_and_private_inputs(&func_sig, &input_witnesses);
 
-    let all_parameters: BTreeSet<Witness> = tree_to_set(&abi.param_witnesses);
-    let private_parameters = all_parameters.difference(&public_parameters.0).copied().collect();
-
-    let return_values = PublicInputs(return_witnesses.into_iter().collect());
+    let public_parameters = PublicInputs(public_parameter_witnesses);
+    let return_values = PublicInputs(return_witnesses.iter().copied().collect());
 
     let circuit = Circuit {
         current_witness_index,
@@ -132,7 +124,41 @@ pub fn create_circuit(
     let (optimized_circuit, transformation_map) = acvm::compiler::optimize(circuit);
     debug_info.update_acir(transformation_map);
 
-    Ok((optimized_circuit, debug_info, abi, warnings))
+    Ok((optimized_circuit, debug_info, input_witnesses, return_witnesses, warnings))
+}
+
+// Takes each function argument and partitions the circuit's inputs witnesses according to its visibility.
+fn split_public_and_private_inputs(
+    func_sig: &FunctionSignature,
+    input_witnesses: &[Witness],
+) -> (BTreeSet<Witness>, BTreeSet<Witness>) {
+    let mut idx = 0_usize;
+    if input_witnesses.is_empty() {
+        return (BTreeSet::new(), BTreeSet::new());
+    }
+
+    func_sig
+        .0
+        .iter()
+        .map(|(_, typ, visibility)| {
+            let num_field_elements_needed = typ.field_count() as usize;
+            let witnesses = input_witnesses[idx..idx + num_field_elements_needed].to_vec();
+            idx += num_field_elements_needed;
+            (visibility, witnesses)
+        })
+        .fold((BTreeSet::new(), BTreeSet::new()), |mut acc, (vis, witnesses)| {
+            // Split witnesses into sets based on their visibility.
+            if *vis == Visibility::Public {
+                for witness in witnesses {
+                    acc.0.insert(witness);
+                }
+            } else {
+                for witness in witnesses {
+                    acc.1.insert(witness);
+                }
+            }
+            (acc.0, acc.1)
+        })
 }
 
 // This is just a convenience object to bundle the ssa with `print_ssa_passes` for debug printing.
@@ -178,15 +204,3 @@ impl SsaBuilder {
         self
     }
 }
-
-// Flatten the witnesses in the map into a BTreeSet
-fn tree_to_set(input: &BTreeMap<String, Vec<Range<Witness>>>) -> BTreeSet<Witness> {
-    let mut result = BTreeSet::new();
-    for range in input.values().flatten() {
-        for i in range.start.witness_index()..range.end.witness_index() {
-            result.insert(Witness(i));
-        }
-    }
-
-    result
-}