feat: Sync from noir (#7332)

Automated pull of development from the
[noir](https://github.com/noir-lang/noir) programming language, a
dependency of Aztec.
BEGIN_COMMIT_OVERRIDE
fix(docs): Fix broken docs link to gihtub
(noir-lang/noir#5398)
chore(docs): Remove persona boxes from the landing page
(noir-lang/noir#5400)
feat: Sync from aztec-packages
(noir-lang/noir#5401)
chore: refactor conversion between `FieldElement` and signed integers
(noir-lang/noir#5397)
fix: ICE when using a comptime let variable in runtime code
(noir-lang/noir#5391)
fix: Don't panic when using undefined variables in the interpreter
(noir-lang/noir#5381)
feat: lsp "find all references"
(noir-lang/noir#5395)
fix: correctly detect signed/unsigned integer overflows/underflows
(noir-lang/noir#5375)
fix: go to definition from aliased use
(noir-lang/noir#5396)
END_COMMIT_OVERRIDE

.noir-sync-commit

@@ -1 +1 @@
-f35614a43cf8c5cfb244d9f6ffc9d63282a63e6d
+70ebf607e566a95ff7eb2c7a0eee7c36465ba5b4

noir/noir-repo/aztec_macros/src/utils/hir_utils.rs

@@ -230,6 +230,7 @@ pub fn inject_global(
         file_id,
         global.attributes.clone(),
         false,
+        false,
     );
 
     // Add the statement to the scope so its path can be looked up later

noir/noir-repo/compiler/noirc_evaluator/Cargo.toml

@@ -21,3 +21,6 @@ im.workspace = true
 serde.workspace = true
 tracing.workspace = true
 chrono = "0.4.37"
+
+[dev-dependencies]
+proptest.workspace = true

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ir/instruction/binary.rs

@@ -329,20 +329,16 @@ fn eval_constant_binary_op(
             }
             let result = function(lhs, rhs)?;
             // Check for overflow
-            if result >= 2u128.pow(*bit_size) {
+            if result >= 1 << *bit_size {
                 return None;
             }
             result.into()
         }
         Type::Numeric(NumericType::Signed { bit_size }) => {
             let function = operator.get_i128_function();
 
-            let lhs = truncate(lhs.try_into_u128()?, *bit_size);
-            let rhs = truncate(rhs.try_into_u128()?, *bit_size);
-            let l_pos = lhs < 2u128.pow(bit_size - 1);
-            let r_pos = rhs < 2u128.pow(bit_size - 1);
-            let lhs = if l_pos { lhs as i128 } else { -((2u128.pow(*bit_size) - lhs) as i128) };
-            let rhs = if r_pos { rhs as i128 } else { -((2u128.pow(*bit_size) - rhs) as i128) };
+            let lhs = try_convert_field_element_to_signed_integer(lhs, *bit_size)?;
+            let rhs = try_convert_field_element_to_signed_integer(rhs, *bit_size)?;
             // The divisor is being truncated into the type of the operand, which can potentially
             // lead to the rhs being zero.
             // If the rhs of a division is zero, attempting to evaluate the division will cause a compiler panic.
@@ -354,12 +350,11 @@ fn eval_constant_binary_op(
 
             let result = function(lhs, rhs)?;
             // Check for overflow
-            if result >= 2i128.pow(*bit_size - 1) || result < -(2i128.pow(*bit_size - 1)) {
+            let two_pow_bit_size_minus_one = 1i128 << (*bit_size - 1);
+            if result >= two_pow_bit_size_minus_one || result < -two_pow_bit_size_minus_one {
                 return None;
             }
-            let result =
-                if result >= 0 { result as u128 } else { (2i128.pow(*bit_size) + result) as u128 };
-            result.into()
+            convert_signed_integer_to_field_element(result, *bit_size)
         }
         _ => return None,
     };
@@ -371,8 +366,37 @@ fn eval_constant_binary_op(
     Some((value, operand_type))
 }
 
+/// Values in the range `[0, 2^(bit_size-1))` are interpreted as positive integers
+///
+/// Values in the range `[2^(bit_size-1), 2^bit_size)` are interpreted as negative integers.
+fn try_convert_field_element_to_signed_integer(field: FieldElement, bit_size: u32) -> Option<i128> {
+    let unsigned_int = truncate(field.try_into_u128()?, bit_size);
+
+    let max_positive_value = 1 << (bit_size - 1);
+    let is_positive = unsigned_int < max_positive_value;
+
+    let signed_int = if is_positive {
+        unsigned_int as i128
+    } else {
+        let x = (1u128 << bit_size) - unsigned_int;
+        -(x as i128)
+    };
+
+    Some(signed_int)
+}
+
+fn convert_signed_integer_to_field_element(int: i128, bit_size: u32) -> FieldElement {
+    if int >= 0 {
+        FieldElement::from(int)
+    } else {
+        // We add an offset of `bit_size` bits to shift the negative values into the range [2^(bitsize-1), 2^bitsize)
+        let offset_int = (1i128 << bit_size) + int;
+        FieldElement::from(offset_int)
+    }
+}
+
 fn truncate(int: u128, bit_size: u32) -> u128 {
-    let max = 2u128.pow(bit_size);
+    let max = 1 << bit_size;
     int % max
 }
 
@@ -429,3 +453,24 @@ impl BinaryOp {
         }
     }
 }
+
+#[cfg(test)]
+mod test {
+    use proptest::prelude::*;
+
+    use super::{
+        convert_signed_integer_to_field_element, try_convert_field_element_to_signed_integer,
+    };
+
+    proptest! {
+        #[test]
+        fn signed_int_roundtrip(int: i128, bit_size in 1u32..=64) {
+            let int = int % (1i128 << (bit_size - 1));
+
+            let int_as_field = convert_signed_integer_to_field_element(int, bit_size);
+            let recovered_int = try_convert_field_element_to_signed_integer(int_as_field, bit_size).unwrap();
+
+            prop_assert_eq!(int, recovered_int);
+        }
+    }
+}

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ir/types.rs

@@ -31,12 +31,20 @@ impl NumericType {
 
     /// Returns true if the given Field value is within the numeric limits
     /// for the current NumericType.
-    pub(crate) fn value_is_within_limits(self, field: FieldElement) -> bool {
+    pub(crate) fn value_is_within_limits(self, field: FieldElement, negative: bool) -> bool {
         match self {
-            NumericType::Signed { bit_size } | NumericType::Unsigned { bit_size } => {
+            NumericType::Unsigned { bit_size } => {
+                if negative {
+                    return false;
+                }
                 let max = 2u128.pow(bit_size) - 1;
                 field <= max.into()
             }
+            NumericType::Signed { bit_size } => {
+                let max =
+                    if negative { 2u128.pow(bit_size - 1) } else { 2u128.pow(bit_size - 1) - 1 };
+                field <= max.into()
+            }
             NumericType::NativeField => true,
         }
     }
@@ -210,3 +218,27 @@ impl std::fmt::Display for NumericType {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_u8_is_within_limits() {
+        let u8 = NumericType::Unsigned { bit_size: 8 };
+        assert!(!u8.value_is_within_limits(FieldElement::from(1_i128), true));
+        assert!(u8.value_is_within_limits(FieldElement::from(0_i128), false));
+        assert!(u8.value_is_within_limits(FieldElement::from(255_i128), false));
+        assert!(!u8.value_is_within_limits(FieldElement::from(256_i128), false));
+    }
+
+    #[test]
+    fn test_i8_is_within_limits() {
+        let i8 = NumericType::Signed { bit_size: 8 };
+        assert!(!i8.value_is_within_limits(FieldElement::from(129_i128), true));
+        assert!(i8.value_is_within_limits(FieldElement::from(128_i128), true));
+        assert!(i8.value_is_within_limits(FieldElement::from(0_i128), false));
+        assert!(i8.value_is_within_limits(FieldElement::from(127_i128), false));
+        assert!(!i8.value_is_within_limits(FieldElement::from(128_i128), false));
+    }
+}

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ssa_gen/context.rs

@@ -266,20 +266,37 @@ impl<'a> FunctionContext<'a> {
     pub(super) fn checked_numeric_constant(
         &mut self,
         value: impl Into<FieldElement>,
+        negative: bool,
         typ: Type,
     ) -> Result<ValueId, RuntimeError> {
         let value = value.into();
 
-        if let Type::Numeric(typ) = typ {
-            if !typ.value_is_within_limits(value) {
+        if let Type::Numeric(numeric_type) = typ {
+            if !numeric_type.value_is_within_limits(value, negative) {
                 let call_stack = self.builder.get_call_stack();
-                return Err(RuntimeError::IntegerOutOfBounds { value, typ, call_stack });
+                return Err(RuntimeError::IntegerOutOfBounds {
+                    value,
+                    typ: numeric_type,
+                    call_stack,
+                });
             }
+
+            let value = if negative {
+                match numeric_type {
+                    NumericType::NativeField => -value,
+                    NumericType::Signed { bit_size } | NumericType::Unsigned { bit_size } => {
+                        let base = 1_u128 << bit_size;
+                        FieldElement::from(base) - value
+                    }
+                }
+            } else {
+                value
+            };
+
+            Ok(self.builder.numeric_constant(value, typ))
         } else {
             panic!("Expected type for numeric constant to be a numeric type, found {typ}");
         }
-
-        Ok(self.builder.numeric_constant(value, typ))
     }
 
     /// helper function which add instructions to the block computing the absolute value of the

noir/noir-repo/compiler/noirc_evaluator/src/ssa/ssa_gen/mod.rs

@@ -219,10 +219,10 @@ impl<'a> FunctionContext<'a> {
                     _ => unreachable!("ICE: unexpected slice literal type, got {}", array.typ),
                 })
             }
-            ast::Literal::Integer(value, typ, location) => {
+            ast::Literal::Integer(value, negative, typ, location) => {
                 self.builder.set_location(*location);
                 let typ = Self::convert_non_tuple_type(typ);
-                self.checked_numeric_constant(*value, typ).map(Into::into)
+                self.checked_numeric_constant(*value, *negative, typ).map(Into::into)
             }
             ast::Literal::Bool(value) => {
                 // Don't need to call checked_numeric_constant here since `value` can only be true or false

noir/noir-repo/compiler/noirc_frontend/src/elaborator/mod.rs

@@ -136,8 +136,6 @@ pub struct Elaborator<'context> {
     /// Each constraint in the `where` clause of the function currently being resolved.
     trait_bounds: Vec<TraitConstraint>,
 
-    current_function: Option<FuncId>,
-
     /// This is a stack of function contexts. Most of the time, for each function we
     /// expect this to be of length one, containing each type variable and trait constraint
     /// used in the function. This is also pushed to when a `comptime {}` block is used within
@@ -196,7 +194,6 @@ impl<'context> Elaborator<'context> {
             crate_id,
             resolving_ids: BTreeSet::new(),
             trait_bounds: Vec::new(),
-            current_function: None,
             function_context: vec![FunctionContext::default()],
             current_trait_impl: None,
             comptime_scopes: vec![HashMap::default()],
@@ -329,8 +326,6 @@ impl<'context> Elaborator<'context> {
             FunctionBody::Resolving => return,
         };
 
-        let old_function = std::mem::replace(&mut self.current_function, Some(id));
-
         self.scopes.start_function();
         let old_item = std::mem::replace(&mut self.current_item, Some(DependencyId::Function(id)));
 
@@ -407,7 +402,6 @@ impl<'context> Elaborator<'context> {
 
         self.trait_bounds.clear();
         self.interner.update_fn(id, hir_func);
-        self.current_function = old_function;
         self.current_item = old_item;
     }
 
@@ -615,8 +609,6 @@ impl<'context> Elaborator<'context> {
         func_id: FuncId,
         is_trait_function: bool,
     ) {
-        self.current_function = Some(func_id);
-
         let in_contract = if self.self_type.is_some() {
             // Without this, impl methods can accidentally be placed in contracts.
             // See: https://github.com/noir-lang/noir/issues/3254
@@ -738,7 +730,6 @@ impl<'context> Elaborator<'context> {
         };
 
         self.interner.push_fn_meta(meta, func_id);
-        self.current_function = None;
         self.scopes.end_function();
         self.current_item = None;
     }
@@ -1468,6 +1459,30 @@ impl<'context> Elaborator<'context> {
         }
     }
 
+    /// True if we're currently within a `comptime` block, function, or global
+    fn in_comptime_context(&self) -> bool {
+        // The first context is the global context, followed by the function-specific context.
+        // Any context after that is a `comptime {}` block's.
+        if self.function_context.len() > 2 {
+            return true;
+        }
+
+        match self.current_item {
+            Some(DependencyId::Function(id)) => self.interner.function_modifiers(&id).is_comptime,
+            Some(DependencyId::Global(id)) => self.interner.get_global_definition(id).comptime,
+            _ => false,
+        }
+    }
+
+    /// True if we're currently within a constrained function.
+    /// Defaults to `true` if the current function is unknown.
+    fn in_constrained_function(&self) -> bool {
+        self.current_item.map_or(true, |id| match id {
+            DependencyId::Function(id) => !self.interner.function_modifiers(&id).is_unconstrained,
+            _ => true,
+        })
+    }
+
     /// Filters out comptime items from non-comptime items.
     /// Returns a pair of (comptime items, non-comptime items)
     fn filter_comptime_items(mut items: CollectedItems) -> (CollectedItems, CollectedItems) {

noir/noir-repo/compiler/noirc_frontend/src/elaborator/patterns.rs

@@ -5,6 +5,7 @@ use rustc_hash::FxHashSet as HashSet;
 use crate::{
     ast::ERROR_IDENT,
     hir::{
+        comptime::Interpreter,
         def_collector::dc_crate::CompilationError,
         resolution::errors::ResolverError,
         type_check::{Source, TypeCheckError},
@@ -285,19 +286,21 @@ impl<'context> Elaborator<'context> {
         }
 
         let location = Location::new(name.span(), self.file);
+        let name = name.0.contents;
+        let comptime = self.in_comptime_context();
         let id =
-            self.interner.push_definition(name.0.contents.clone(), mutable, definition, location);
+            self.interner.push_definition(name.clone(), mutable, comptime, definition, location);
         let ident = HirIdent::non_trait_method(id, location);
         let resolver_meta =
             ResolverMeta { num_times_used: 0, ident: ident.clone(), warn_if_unused };
 
         let scope = self.scopes.get_mut_scope();
-        let old_value = scope.add_key_value(name.0.contents.clone(), resolver_meta);
+        let old_value = scope.add_key_value(name.clone(), resolver_meta);
 
         if !allow_shadowing {
             if let Some(old_value) = old_value {
                 self.push_err(ResolverError::DuplicateDefinition {
-                    name: name.0.contents,
+                    name,
                     first_span: old_value.ident.location.span,
                     second_span: location.span,
                 });
@@ -329,6 +332,7 @@ impl<'context> Elaborator<'context> {
         name: Ident,
         definition: DefinitionKind,
     ) -> HirIdent {
+        let comptime = self.in_comptime_context();
         let scope = self.scopes.get_mut_scope();
 
         // This check is necessary to maintain the same definition ids in the interner. Currently, each function uses a new resolver that has its own ScopeForest and thus global scope.
@@ -350,8 +354,8 @@ impl<'context> Elaborator<'context> {
             (hir_ident, resolver_meta)
         } else {
             let location = Location::new(name.span(), self.file);
-            let id =
-                self.interner.push_definition(name.0.contents.clone(), false, definition, location);
+            let name = name.0.contents.clone();
+            let id = self.interner.push_definition(name, false, comptime, definition, location);
             let ident = HirIdent::non_trait_method(id, location);
             let resolver_meta =
                 ResolverMeta { num_times_used: 0, ident: ident.clone(), warn_if_unused: true };
@@ -400,12 +404,24 @@ impl<'context> Elaborator<'context> {
     ) -> (ExprId, Type) {
         let span = variable.span;
         let expr = self.resolve_variable(variable);
+        let definition_id = expr.id;
 
         let id = self.interner.push_expr(HirExpression::Ident(expr.clone(), generics.clone()));
 
         self.interner.push_expr_location(id, span, self.file);
         let typ = self.type_check_variable(expr, id, generics);
         self.interner.push_expr_type(id, typ.clone());
+
+        // Comptime variables must be replaced with their values
+        if let Some(definition) = self.interner.try_definition(definition_id) {
+            if definition.comptime && !self.in_comptime_context() {
+                let mut interpreter =
+                    Interpreter::new(self.interner, &mut self.comptime_scopes, self.crate_id);
+                let value = interpreter.evaluate(id);
+                return self.inline_comptime_value(value, span);
+            }
+        }
+
         (id, typ)
     }