Merge branch 'master' into jz/docs-add-writing-noir

acvm-repo/acir/src/native_types/expression/mod.rs

@@ -273,6 +273,60 @@ impl<F: AcirField> Expression<F> {
 
         Expression { mul_terms, linear_combinations, q_c }
     }
+
+    /// Determine the width of this expression.
+    /// The width meaning the number of unique witnesses needed for this expression.
+    pub fn width(&self) -> usize {
+        let mut width = 0;
+
+        for mul_term in &self.mul_terms {
+            // The coefficient should be non-zero, as this method is ran after the compiler removes all zero coefficient terms
+            assert_ne!(mul_term.0, F::zero());
+
+            let mut found_x = false;
+            let mut found_y = false;
+
+            for term in self.linear_combinations.iter() {
+                let witness = &term.1;
+                let x = &mul_term.1;
+                let y = &mul_term.2;
+                if witness == x {
+                    found_x = true;
+                };
+                if witness == y {
+                    found_y = true;
+                };
+                if found_x & found_y {
+                    break;
+                }
+            }
+
+            // If the multiplication is a squaring then we must assign the two witnesses to separate wires and so we
+            // can never get a zero contribution to the width.
+            let multiplication_is_squaring = mul_term.1 == mul_term.2;
+
+            let mul_term_width_contribution = if !multiplication_is_squaring && (found_x & found_y)
+            {
+                // Both witnesses involved in the multiplication exist elsewhere in the expression.
+                // They both do not contribute to the width of the expression as this would be double-counting
+                // due to their appearance in the linear terms.
+                0
+            } else if found_x || found_y {
+                // One of the witnesses involved in the multiplication exists elsewhere in the expression.
+                // The multiplication then only contributes 1 new witness to the width.
+                1
+            } else {
+                // Worst case scenario, the multiplication is using completely unique witnesses so has a contribution of 2.
+                2
+            };
+
+            width += mul_term_width_contribution;
+        }
+
+        width += self.linear_combinations.len();
+
+        width
+    }
 }
 
 impl<F: AcirField> From<F> for Expression<F> {

acvm-repo/acvm/src/compiler/transformers/csat.rs

@@ -415,71 +415,8 @@ fn fits_in_one_identity<F: AcirField>(expr: &Expression<F>, width: usize) -> boo
     if expr.mul_terms.len() > 1 {
         return false;
     };
-    // A Polynomial with more terms than fan-in cannot fit within a single opcode
-    if expr.linear_combinations.len() > width {
-        return false;
-    }
-
-    // A polynomial with no mul term and a fan-in that fits inside of the width can fit into a single opcode
-    if expr.mul_terms.is_empty() {
-        return true;
-    }
-
-    // A polynomial with width-2 fan-in terms and a single non-zero mul term can fit into one opcode
-    // Example: Axy + Dz . Notice, that the mul term places a constraint on the first two terms, but not the last term
-    // XXX: This would change if our arithmetic polynomial equation was changed to Axyz for example, but for now it is not.
-    if expr.linear_combinations.len() <= (width - 2) {
-        return true;
-    }
-
-    // We now know that we have a single mul term. We also know that the mul term must match up with at least one of the other terms
-    // A polynomial whose mul terms are non zero which do not match up with two terms in the fan-in cannot fit into one opcode
-    // An example of this is: Axy + Bx + Cy + ...
-    // Notice how the bivariate monomial xy has two univariate monomials with their respective coefficients
-    // XXX: note that if x or y is zero, then we could apply a further optimization, but this would be done in another algorithm.
-    // It would be the same as when we have zero coefficients - Can only work if wire is constrained to be zero publicly
-    let mul_term = &expr.mul_terms[0];
-
-    // The coefficient should be non-zero, as this method is ran after the compiler removes all zero coefficient terms
-    assert_ne!(mul_term.0, F::zero());
-
-    let mut found_x = false;
-    let mut found_y = false;
-
-    for term in expr.linear_combinations.iter() {
-        let witness = &term.1;
-        let x = &mul_term.1;
-        let y = &mul_term.2;
-        if witness == x {
-            found_x = true;
-        };
-        if witness == y {
-            found_y = true;
-        };
-        if found_x & found_y {
-            break;
-        }
-    }
-
-    // If the multiplication is a squaring then we must assign the two witnesses to separate wires and so we
-    // can never get a zero contribution to the width.
-    let multiplication_is_squaring = mul_term.1 == mul_term.2;
-
-    let mul_term_width_contribution = if !multiplication_is_squaring && (found_x & found_y) {
-        // Both witnesses involved in the multiplication exist elsewhere in the expression.
-        // They both do not contribute to the width of the expression as this would be double-counting
-        // due to their appearance in the linear terms.
-        0
-    } else if found_x || found_y {
-        // One of the witnesses involved in the multiplication exists elsewhere in the expression.
-        // The multiplication then only contributes 1 new witness to the width.
-        1
-    } else {
-        // Worst case scenario, the multiplication is using completely unique witnesses so has a contribution of 2.
-        2
-    };
 
-    mul_term_width_contribution + expr.linear_combinations.len() <= width
+    expr.width() <= width
 }
 
 #[cfg(test)]

aztec_macros/src/transforms/functions.rs

@@ -17,7 +17,8 @@ use crate::{
         ast_utils::{
             assignment, assignment_with_type, call, cast, expression, ident, ident_path,
             index_array, make_eq, make_statement, make_type, method_call, mutable_assignment,
-            mutable_reference, path, return_type, variable, variable_ident, variable_path,
+            mutable_reference, path, path_segment, return_type, variable, variable_ident,
+            variable_path,
         },
         errors::AztecMacroError,
     },
@@ -722,8 +723,8 @@ fn add_struct_to_hasher(identifier: &Ident, hasher_name: &str) -> Statement {
 fn str_to_bytes(identifier: &Ident) -> (Statement, Ident) {
     // let identifier_as_bytes = identifier.as_bytes();
     let var = variable_ident(identifier.clone());
-    let contents = if let ExpressionKind::Variable(p, _) = &var.kind {
-        p.segments.first().cloned().unwrap_or_else(|| panic!("No segments")).0.contents
+    let contents = if let ExpressionKind::Variable(p) = &var.kind {
+        p.first_name()
     } else {
         panic!("Unexpected identifier type")
     };

aztec_macros/src/transforms/note_interface.rs

@@ -21,6 +21,7 @@ use crate::{
     utils::{
         ast_utils::{
             check_trait_method_implemented, ident, ident_path, is_custom_attribute, make_type,
+            path_segment,
         },
         errors::AztecMacroError,
         hir_utils::{fetch_notes, get_contract_module_data, inject_global},
@@ -45,8 +46,8 @@ pub fn generate_note_interface_impl(module: &mut SortedModule) -> Result<(), Azt
             .iter_mut()
             .find(|trait_impl| {
                 if let UnresolvedTypeData::Named(struct_path, _, _) = &trait_impl.object_type.typ {
-                    struct_path.last_segment() == note_struct.name
-                        && trait_impl.trait_name.last_segment().0.contents == "NoteInterface"
+                    struct_path.last_ident() == note_struct.name
+                        && trait_impl.trait_name.last_name() == "NoteInterface"
                 } else {
                     false
                 }
@@ -61,7 +62,7 @@ pub fn generate_note_interface_impl(module: &mut SortedModule) -> Result<(), Azt
         let note_interface_impl_span: Option<Span> = trait_impl.object_type.span;
         // Look for the note struct implementation, generate a default one if it doesn't exist (in order to append methods to it)
         let existing_impl = module.impls.iter_mut().find(|r#impl| match &r#impl.object_type.typ {
-            UnresolvedTypeData::Named(path, _, _) => path.last_segment().eq(&note_struct.name),
+            UnresolvedTypeData::Named(path, _, _) => path.last_ident().eq(&note_struct.name),
             _ => false,
         });
         let note_impl = if let Some(note_impl) = existing_impl {
@@ -73,7 +74,6 @@ pub fn generate_note_interface_impl(module: &mut SortedModule) -> Result<(), Azt
                 generics: vec![],
                 methods: vec![],
                 where_clause: vec![],
-                is_comptime: false,
             };
             module.impls.push(default_impl.clone());
             module.impls.last_mut().unwrap()
@@ -85,9 +85,7 @@ pub fn generate_note_interface_impl(module: &mut SortedModule) -> Result<(), Azt
             .trait_generics
             .iter()
             .map(|gen| match gen.typ.clone() {
-                UnresolvedTypeData::Named(path, _, _) => {
-                    Ok(path.last_segment().0.contents.to_string())
-                }
+                UnresolvedTypeData::Named(path, _, _) => Ok(path.last_name().to_string()),
                 UnresolvedTypeData::Expression(UnresolvedTypeExpression::Constant(val, _)) => {
                     Ok(val.to_string())
                 }
@@ -106,9 +104,7 @@ pub fn generate_note_interface_impl(module: &mut SortedModule) -> Result<(), Azt
         // Automatically inject the header field if it's not present
         let (header_field_name, _) = if let Some(existing_header) =
             note_struct.fields.iter().find(|(_, field_type)| match &field_type.typ {
-                UnresolvedTypeData::Named(path, _, _) => {
-                    path.last_segment().0.contents == "NoteHeader"
-                }
+                UnresolvedTypeData::Named(path, _, _) => path.last_name() == "NoteHeader",
                 _ => false,
             }) {
             existing_header.clone()

aztec_macros/src/transforms/storage.rs

@@ -21,7 +21,7 @@ use crate::{
     utils::{
         ast_utils::{
             call, expression, ident, ident_path, is_custom_attribute, lambda, make_statement,
-            make_type, pattern, return_type, variable, variable_path,
+            make_type, path_segment, pattern, return_type, variable, variable_path,
         },
         errors::AztecMacroError,
         hir_utils::{
@@ -59,7 +59,7 @@ fn inject_context_in_storage_field(field: &mut UnresolvedType) -> Result<(), Azt
                 vec![],
                 false,
             )));
-            match path.segments.last().unwrap().0.contents.as_str() {
+            match path.last_name() {
                 "Map" => inject_context_in_storage_field(&mut generics[1]),
                 _ => Ok(()),
             }
@@ -106,9 +106,7 @@ pub fn check_for_storage_implementation(
     storage_struct_name: &String,
 ) -> bool {
     module.impls.iter().any(|r#impl| match &r#impl.object_type.typ {
-        UnresolvedTypeData::Named(path, _, _) => {
-            path.segments.last().is_some_and(|segment| segment.0.contents == *storage_struct_name)
-        }
+        UnresolvedTypeData::Named(path, _, _) => path.last_name() == *storage_struct_name,
         _ => false,
     })
 }
@@ -123,8 +121,8 @@ pub fn generate_storage_field_constructor(
     match typ {
         UnresolvedTypeData::Named(path, generics, _) => {
             let mut new_path = path.clone().to_owned();
-            new_path.segments.push(ident("new"));
-            match path.segments.last().unwrap().0.contents.as_str() {
+            new_path.segments.push(path_segment("new"));
+            match path.last_name() {
                 "Map" => Ok(call(
                     variable_path(new_path),
                     vec![
@@ -248,7 +246,6 @@ pub fn generate_storage_implementation(
         methods: vec![(init, Span::default())],
 
         where_clause: vec![],
-        is_comptime: false,
     };
     module.impls.push(storage_impl);
 

aztec_macros/src/utils/ast_utils.rs

@@ -2,8 +2,8 @@ use noirc_errors::{Span, Spanned};
 use noirc_frontend::ast::{
     BinaryOpKind, CallExpression, CastExpression, Expression, ExpressionKind, FunctionReturnType,
     Ident, IndexExpression, InfixExpression, Lambda, LetStatement, MemberAccessExpression,
-    MethodCallExpression, NoirTraitImpl, Path, Pattern, PrefixExpression, Statement, StatementKind,
-    TraitImplItem, UnaryOp, UnresolvedType, UnresolvedTypeData,
+    MethodCallExpression, NoirTraitImpl, Path, PathSegment, Pattern, PrefixExpression, Statement,
+    StatementKind, TraitImplItem, UnaryOp, UnresolvedType, UnresolvedTypeData,
 };
 use noirc_frontend::token::SecondaryAttribute;
 
@@ -18,6 +18,10 @@ pub fn ident_path(name: &str) -> Path {
     Path::from_ident(ident(name))
 }
 
+pub fn path_segment(name: &str) -> PathSegment {
+    PathSegment::from(ident(name))
+}
+
 pub fn path(ident: Ident) -> Path {
     Path::from_ident(ident)
 }
@@ -27,15 +31,15 @@ pub fn expression(kind: ExpressionKind) -> Expression {
 }
 
 pub fn variable(name: &str) -> Expression {
-    expression(ExpressionKind::Variable(ident_path(name), None))
+    expression(ExpressionKind::Variable(ident_path(name)))
 }
 
 pub fn variable_ident(identifier: Ident) -> Expression {
-    expression(ExpressionKind::Variable(path(identifier), None))
+    expression(ExpressionKind::Variable(path(identifier)))
 }
 
 pub fn variable_path(path: Path) -> Expression {
-    expression(ExpressionKind::Variable(path, None))
+    expression(ExpressionKind::Variable(path))
 }
 
 pub fn method_call(
@@ -149,7 +153,7 @@ macro_rules! chained_path {
         {
             let mut base_path = ident_path($base);
             $(
-                base_path.segments.push(ident($tail));
+                base_path.segments.push(path_segment($tail));
             )*
             base_path
         }
@@ -163,7 +167,7 @@ macro_rules! chained_dep {
             let mut base_path = ident_path($base);
             base_path.kind = PathKind::Plain;
             $(
-                base_path.segments.push(ident($tail));
+                base_path.segments.push(path_segment($tail));
             )*
             base_path
         }

aztec_macros/src/utils/hir_utils.rs

@@ -221,6 +221,7 @@ pub fn inject_global(
     let global_id = context.def_interner.push_empty_global(
         name.clone(),
         module_id,
+        *crate_id,
         file_id,
         global.attributes.clone(),
         false,

compiler/noirc_driver/src/abi_gen.rs

@@ -116,7 +116,7 @@ fn to_abi_visibility(value: Visibility) -> AbiVisibility {
     match value {
         Visibility::Public => AbiVisibility::Public,
         Visibility::Private => AbiVisibility::Private,
-        Visibility::DataBus => AbiVisibility::DataBus,
+        Visibility::CallData(_) | Visibility::ReturnData => AbiVisibility::DataBus,
     }
 }
 

compiler/noirc_driver/src/lib.rs

@@ -56,6 +56,12 @@ pub struct CompileOptions {
     #[arg(long, value_parser = parse_expression_width)]
     pub expression_width: Option<ExpressionWidth>,
 
+    /// Generate ACIR with the target backend expression width.
+    /// The default is to generate ACIR without a bound and split expressions after code generation.
+    /// Activating this flag can sometimes provide optimizations for certain programs.
+    #[arg(long, default_value = "false")]
+    pub bounded_codegen: bool,
+
     /// Force a full recompilation.
     #[arg(long = "force")]
     pub force_compile: bool,
@@ -512,6 +518,12 @@ fn compile_contract_inner(
     }
 }
 
+/// Default expression width used for Noir compilation.
+/// The ACVM native type `ExpressionWidth` has its own default which should always be unbounded,
+/// while we can sometimes expect the compilation target width to change.
+/// Thus, we set it separately here rather than trying to alter the default derivation of the type.
+pub const DEFAULT_EXPRESSION_WIDTH: ExpressionWidth = ExpressionWidth::Bounded { width: 4 };
+
 /// Compile the current crate using `main_function` as the entrypoint.
 ///
 /// This function assumes [`check_crate`] is called beforehand.
@@ -550,6 +562,11 @@ pub fn compile_no_check(
         enable_brillig_logging: options.show_brillig,
         force_brillig_output: options.force_brillig,
         print_codegen_timings: options.benchmark_codegen,
+        expression_width: if options.bounded_codegen {
+            options.expression_width.unwrap_or(DEFAULT_EXPRESSION_WIDTH)
+        } else {
+            ExpressionWidth::default()
+        },
     };
 
     let SsaProgramArtifact { program, debug, warnings, names, error_types, .. } =