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cairo_lang_semantic/items/
constant.rs

1use std::iter::zip;
2use std::sync::Arc;
3
4use cairo_lang_debug::DebugWithDb;
5use cairo_lang_defs::db::DefsGroup;
6use cairo_lang_defs::ids::{
7    ConstantId, ExternFunctionId, GenericParamId, LanguageElementId, LookupItemId, ModuleItemId,
8    NamedLanguageElementId, TopLevelLanguageElementId, TraitConstantId, TraitId, VarId,
9};
10use cairo_lang_diagnostics::{
11    DiagnosticAdded, DiagnosticEntry, DiagnosticNote, Diagnostics, Maybe, MaybeAsRef,
12    skip_diagnostic,
13};
14use cairo_lang_proc_macros::{DebugWithDb, HeapSize, SemanticObject};
15use cairo_lang_syntax::node::ast::ItemConstant;
16use cairo_lang_syntax::node::ids::SyntaxStablePtrId;
17use cairo_lang_syntax::node::{TypedStablePtr, TypedSyntaxNode};
18use cairo_lang_utils::ordered_hash_map::OrderedHashMap;
19use cairo_lang_utils::ordered_hash_set::OrderedHashSet;
20use cairo_lang_utils::unordered_hash_map::UnorderedHashMap;
21use cairo_lang_utils::unordered_hash_set::UnorderedHashSet;
22use cairo_lang_utils::{Intern, define_short_id, extract_matches, require, try_extract_matches};
23use itertools::Itertools;
24use num_bigint::BigInt;
25use num_traits::{ToPrimitive, Zero};
26use salsa::Database;
27use starknet_types_core::felt::{CAIRO_PRIME_BIGINT, Felt as Felt252};
28
29use super::functions::{GenericFunctionId, GenericFunctionWithBodyId};
30use super::imp::{ImplId, ImplLongId};
31use crate::corelib::{
32    CoreInfo, CorelibSemantic, core_nonzero_ty, false_variant, true_variant,
33    try_extract_bounded_int_type_ranges, try_extract_nz_wrapped_type, unit_ty, validate_literal,
34};
35use crate::diagnostic::{SemanticDiagnosticKind, SemanticDiagnostics, SemanticDiagnosticsBuilder};
36use crate::expr::compute::{ComputationContext, ExprAndId, compute_expr_semantic};
37use crate::expr::inference::conform::InferenceConform;
38use crate::expr::inference::{ConstVar, InferenceId};
39use crate::helper::ModuleHelper;
40use crate::items::enm::SemanticEnumEx;
41use crate::items::extern_function::ExternFunctionSemantic;
42use crate::items::free_function::FreeFunctionSemantic;
43use crate::items::function_with_body::FunctionWithBodySemantic;
44use crate::items::generics::GenericParamSemantic;
45use crate::items::imp::ImplSemantic;
46use crate::items::structure::StructSemantic;
47use crate::items::trt::TraitSemantic;
48use crate::resolve::{Resolver, ResolverData};
49use crate::substitution::{GenericSubstitution, SemanticRewriter};
50use crate::types::resolve_type;
51use crate::{
52    Arenas, ConcreteFunction, ConcreteTypeId, ConcreteVariant, Condition, Expr, ExprBlock,
53    ExprConstant, ExprFunctionCall, ExprFunctionCallArg, ExprId, ExprMemberAccess, ExprStructCtor,
54    FunctionId, GenericParam, LogicalOperator, Pattern, PatternId, SemanticDiagnostic, Statement,
55    TypeId, TypeLongId, semantic_object_for_id,
56};
57
58#[derive(Clone, Debug, PartialEq, Eq, DebugWithDb)]
59#[debug_db(dyn Database)]
60pub struct Constant<'db> {
61    /// The actual id of the const expression value.
62    pub value: ExprId,
63    /// The arena of all the expressions for the const calculation.
64    pub arenas: Arc<Arenas<'db>>,
65}
66
67// TODO: Review this well.
68unsafe impl<'db> salsa::Update for Constant<'db> {
69    unsafe fn maybe_update(old_pointer: *mut Self, new_value: Self) -> bool {
70        let old_constant: &mut Constant<'db> = unsafe { &mut *old_pointer };
71
72        if old_constant.value != new_value.value {
73            *old_constant = new_value;
74            return true;
75        }
76
77        false
78    }
79}
80
81impl<'db> Constant<'db> {
82    pub fn ty(&self) -> TypeId<'db> {
83        self.arenas.exprs[self.value].ty()
84    }
85}
86
87/// Information about a constant definition.
88///
89/// Helper struct for the data returned by [ConstantSemantic::constant_semantic_data].
90#[derive(Clone, Debug, PartialEq, Eq, DebugWithDb, salsa::Update)]
91#[debug_db(dyn Database)]
92pub struct ConstantData<'db> {
93    pub diagnostics: Diagnostics<'db, SemanticDiagnostic<'db>>,
94    pub constant: Maybe<Constant<'db>>,
95    pub const_value: ConstValueId<'db>,
96    pub resolver_data: Arc<ResolverData<'db>>,
97}
98
99define_short_id!(ConstValueId, ConstValue<'db>);
100semantic_object_for_id!(ConstValueId, ConstValue<'a>);
101impl<'db> ConstValueId<'db> {
102    /// Creates a new const value from a BigInt.
103    pub fn from_int(db: &'db dyn Database, ty: TypeId<'db>, value: &BigInt) -> Self {
104        let get_basic_const_value = |ty| {
105            let info = db.const_calc_info();
106            if ty != info.u256 {
107                ConstValue::Int(value.clone(), ty).intern(db)
108            } else {
109                let mask128 = BigInt::from(u128::MAX);
110                let low = value & mask128;
111                let high = value >> 128;
112                ConstValue::Struct(
113                    vec![
114                        (ConstValue::Int(low, info.u128).intern(db)),
115                        (ConstValue::Int(high, info.u128).intern(db)),
116                    ],
117                    ty,
118                )
119                .intern(db)
120            }
121        };
122        if let Some(inner) = try_extract_nz_wrapped_type(db, ty) {
123            ConstValue::NonZero(get_basic_const_value(inner)).intern(db)
124        } else {
125            get_basic_const_value(ty)
126        }
127    }
128    /// Returns a formatted string of the const value.
129    pub fn format(&self, db: &dyn Database) -> String {
130        format!("{:?}", self.long(db).debug(db))
131    }
132
133    /// Returns true if the const does not depend on any generics.
134    pub fn is_fully_concrete(&self, db: &dyn Database) -> bool {
135        self.long(db).is_fully_concrete(db)
136    }
137
138    /// Returns true if the const does not contain any inference variables.
139    pub fn is_var_free(&self, db: &dyn Database) -> bool {
140        self.long(db).is_var_free(db)
141    }
142
143    /// Returns the type of the const.
144    pub fn ty(&self, db: &'db dyn Database) -> Maybe<TypeId<'db>> {
145        self.long(db).ty(db)
146    }
147
148    /// A utility function for extracting the generic parameters arguments from a ConstValueId.
149    pub fn extract_generic_params(
150        &self,
151        db: &'db dyn Database,
152        generic_parameters: &mut OrderedHashSet<GenericParamId<'db>>,
153    ) -> Maybe<()> {
154        match self.long(db) {
155            ConstValue::Int(_, type_id) | ConstValue::Struct(_, type_id) => {
156                type_id.long(db).extract_generic_params(db, generic_parameters)?
157            }
158            ConstValue::Enum(_, const_value_id) => {
159                const_value_id.ty(db)?.long(db).extract_generic_params(db, generic_parameters)?
160            }
161            ConstValue::NonZero(const_value_id) => {
162                const_value_id.extract_generic_params(db, generic_parameters)?
163            }
164            ConstValue::Generic(generic_param_id) => {
165                generic_parameters.insert(*generic_param_id);
166            }
167            ConstValue::ImplConstant(impl_constant_id) => {
168                for garg in impl_constant_id.impl_id().concrete_trait(db)?.generic_args(db) {
169                    garg.extract_generic_params(db, generic_parameters)?;
170                }
171            }
172            ConstValue::Var(_, type_id) => {
173                type_id.long(db).extract_generic_params(db, generic_parameters)?
174            }
175            ConstValue::Missing(diagnostic_added) => return Err(*diagnostic_added),
176        }
177        Ok(())
178    }
179}
180
181/// Moves the value of a felt252, to the range of `[range_min, range_min + PRIME)`.
182pub fn felt252_for_downcast(value: &BigInt, range_min: &BigInt) -> BigInt {
183    Felt252::from(value - range_min).to_bigint() + range_min
184}
185
186/// Canonicalize the value of a felt252, to the range of `(-PRIME, PRIME)`.
187pub fn canonical_felt252(value: &BigInt) -> BigInt {
188    value % &*CAIRO_PRIME_BIGINT
189}
190
191/// A constant value.
192#[derive(Clone, Debug, Hash, PartialEq, Eq, SemanticObject, HeapSize, salsa::Update)]
193pub enum ConstValue<'db> {
194    Int(#[dont_rewrite] BigInt, TypeId<'db>),
195    Struct(Vec<ConstValueId<'db>>, TypeId<'db>),
196    Enum(ConcreteVariant<'db>, ConstValueId<'db>),
197    NonZero(ConstValueId<'db>),
198    Generic(#[dont_rewrite] GenericParamId<'db>),
199    ImplConstant(ImplConstantId<'db>),
200    Var(ConstVar<'db>, TypeId<'db>),
201    /// A missing value, used in cases where the value is not known due to diagnostics.
202    Missing(#[dont_rewrite] DiagnosticAdded),
203}
204impl<'db> ConstValue<'db> {
205    /// Returns true if the const does not depend on any generics.
206    pub fn is_fully_concrete(&self, db: &dyn Database) -> bool {
207        self.ty(db).unwrap().is_fully_concrete(db)
208            && match self {
209                ConstValue::Int(_, _) => true,
210                ConstValue::Struct(members, _) => {
211                    members.iter().all(|member| member.is_fully_concrete(db))
212                }
213                ConstValue::Enum(_, val) | ConstValue::NonZero(val) => val.is_fully_concrete(db),
214                ConstValue::Generic(_)
215                | ConstValue::Var(_, _)
216                | ConstValue::Missing(_)
217                | ConstValue::ImplConstant(_) => false,
218            }
219    }
220
221    /// Returns true if the const does not contain any inference variables.
222    pub fn is_var_free(&self, db: &dyn Database) -> bool {
223        self.ty(db).unwrap().is_var_free(db)
224            && match self {
225                ConstValue::Int(_, _) | ConstValue::Generic(_) | ConstValue::Missing(_) => true,
226                ConstValue::Struct(members, _) => {
227                    members.iter().all(|member| member.is_var_free(db))
228                }
229                ConstValue::Enum(_, val) | ConstValue::NonZero(val) => val.is_var_free(db),
230                ConstValue::Var(_, _) => false,
231                ConstValue::ImplConstant(impl_constant) => impl_constant.impl_id().is_var_free(db),
232            }
233    }
234
235    /// Returns the type of the const.
236    pub fn ty(&self, db: &'db dyn Database) -> Maybe<TypeId<'db>> {
237        Ok(match self {
238            ConstValue::Int(_, ty) => *ty,
239            ConstValue::Struct(_, ty) => *ty,
240            ConstValue::Enum(variant, _) => {
241                TypeLongId::Concrete(ConcreteTypeId::Enum(variant.concrete_enum_id)).intern(db)
242            }
243            ConstValue::NonZero(value) => core_nonzero_ty(db, value.ty(db)?),
244            ConstValue::Generic(param) => {
245                extract_matches!(db.generic_param_semantic(*param)?, GenericParam::Const).ty
246            }
247            ConstValue::Var(_, ty) => *ty,
248            ConstValue::Missing(_) => TypeId::missing(db, skip_diagnostic()),
249            ConstValue::ImplConstant(impl_constant_id) => {
250                db.impl_constant_concrete_implized_type(*impl_constant_id)?
251            }
252        })
253    }
254
255    /// Returns the value of an int const as a BigInt.
256    pub fn to_int(&self) -> Option<&BigInt> {
257        match self {
258            ConstValue::Int(value, _) => Some(value),
259            _ => None,
260        }
261    }
262}
263
264/// An impl item of kind const.
265#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq, SemanticObject, HeapSize, salsa::Update)]
266pub struct ImplConstantId<'db> {
267    /// The impl the item const is in.
268    impl_id: ImplId<'db>,
269    /// The trait const this impl const "implements".
270    trait_constant_id: TraitConstantId<'db>,
271}
272
273impl<'db> ImplConstantId<'db> {
274    /// Creates a new impl constant id. For an impl constant of a concrete impl, asserts that the
275    /// trait constant belongs to the same trait that the impl implements (panics if not).
276    pub fn new(
277        impl_id: ImplId<'db>,
278        trait_constant_id: TraitConstantId<'db>,
279        db: &dyn Database,
280    ) -> Self {
281        if let ImplLongId::Concrete(concrete_impl) = impl_id.long(db) {
282            let impl_def_id = concrete_impl.impl_def_id(db);
283            assert_eq!(Ok(trait_constant_id.trait_id(db)), db.impl_def_trait(impl_def_id));
284        }
285
286        ImplConstantId { impl_id, trait_constant_id }
287    }
288    pub fn impl_id(&self) -> ImplId<'db> {
289        self.impl_id
290    }
291    pub fn trait_constant_id(&self) -> TraitConstantId<'db> {
292        self.trait_constant_id
293    }
294
295    pub fn format(&self, db: &dyn Database) -> String {
296        format!("{}::{}", self.impl_id.name(db), self.trait_constant_id.name(db).long(db))
297    }
298}
299impl<'db> DebugWithDb<'db> for ImplConstantId<'db> {
300    type Db = dyn Database;
301
302    fn fmt(&self, f: &mut std::fmt::Formatter<'_>, db: &'db dyn Database) -> std::fmt::Result {
303        write!(f, "{}", self.format(db))
304    }
305}
306
307/// Returns the semantic data of a constant.
308#[salsa::tracked(returns(ref), cycle_result=constant_semantic_data_cycle)]
309fn constant_semantic_data<'db>(
310    db: &'db dyn Database,
311    const_id: ConstantId<'db>,
312    in_cycle: bool,
313) -> Maybe<ConstantData<'db>> {
314    let lookup_item_id = LookupItemId::ModuleItem(ModuleItemId::Constant(const_id));
315    if in_cycle {
316        constant_semantic_data_cycle_helper(
317            db,
318            &db.module_constant_by_id(const_id)?,
319            lookup_item_id,
320            None,
321            &const_id,
322        )
323    } else {
324        constant_semantic_data_helper(
325            db,
326            &db.module_constant_by_id(const_id)?,
327            lookup_item_id,
328            None,
329            &const_id,
330        )
331    }
332}
333
334/// Cycle handling for [ConstantSemantic::constant_semantic_data].
335fn constant_semantic_data_cycle<'db>(
336    db: &'db dyn Database,
337    _id: salsa::Id,
338    const_id: ConstantId<'db>,
339    _in_cycle: bool,
340) -> Maybe<ConstantData<'db>> {
341    let lookup_item_id = LookupItemId::ModuleItem(ModuleItemId::Constant(const_id));
342    constant_semantic_data_cycle_helper(
343        db,
344        &db.module_constant_by_id(const_id)?,
345        lookup_item_id,
346        None,
347        &const_id,
348    )
349}
350
351/// Returns constant semantic data for the given ItemConstant.
352pub fn constant_semantic_data_helper<'db>(
353    db: &'db dyn Database,
354    constant_ast: &ItemConstant<'db>,
355    lookup_item_id: LookupItemId<'db>,
356    parent_resolver_data: Option<Arc<ResolverData<'db>>>,
357    element_id: &impl LanguageElementId<'db>,
358) -> Maybe<ConstantData<'db>> {
359    let module_id = element_id.parent_module(db);
360    let mut diagnostics: SemanticDiagnostics<'_> = SemanticDiagnostics::new(module_id);
361    // TODO(spapini): when code changes in a file, all the AST items change (as they contain a path
362    // to the green root that changes. Once ASTs are rooted on items, use a selector that picks only
363    // the item instead of all the module data.
364
365    let inference_id = InferenceId::LookupItemDeclaration(lookup_item_id);
366
367    let mut resolver = match parent_resolver_data {
368        Some(parent_resolver_data) => {
369            Resolver::with_data(db, parent_resolver_data.clone_with_inference_id(db, inference_id))
370        }
371        None => Resolver::new(db, module_id, inference_id),
372    };
373    resolver.set_feature_config(element_id, constant_ast, &mut diagnostics);
374
375    let ty_syntax = constant_ast.type_clause(db).ty(db);
376    let constant_type = resolve_type(db, &mut diagnostics, &mut resolver, &ty_syntax);
377    // The type of a constant must not rely on its value, to create better stability for the
378    // constant signature.
379    if !constant_type.is_var_free(db) {
380        diagnostics.report(
381            ty_syntax.stable_ptr(db).untyped(),
382            SemanticDiagnosticKind::ConstTypeNotVarFree,
383        );
384    }
385
386    let mut ctx = ComputationContext::new_global(db, &mut diagnostics, &mut resolver);
387
388    let value = compute_expr_semantic(&mut ctx, &constant_ast.value(db));
389    let const_value = resolve_const_expr_and_evaluate(
390        db,
391        &mut ctx,
392        &value,
393        constant_ast.stable_ptr(db).untyped(),
394        constant_type,
395        true,
396    );
397    let constant = Ok(Constant { value: value.id, arenas: Arc::new(ctx.arenas) });
398    let const_value = resolver
399        .inference()
400        .rewrite(const_value)
401        .unwrap_or_else(|_| ConstValue::Missing(skip_diagnostic()).intern(db));
402    let resolver_data = Arc::new(resolver.data);
403    Ok(ConstantData { diagnostics: diagnostics.build(), const_value, constant, resolver_data })
404}
405
406/// Helper for cycle handling of constants.
407pub fn constant_semantic_data_cycle_helper<'db>(
408    db: &'db dyn Database,
409    constant_ast: &ItemConstant<'db>,
410    lookup_item_id: LookupItemId<'db>,
411    parent_resolver_data: Option<Arc<ResolverData<'db>>>,
412    element_id: &impl LanguageElementId<'db>,
413) -> Maybe<ConstantData<'db>> {
414    let module_id = element_id.parent_module(db);
415    let mut diagnostics: SemanticDiagnostics<'_> = SemanticDiagnostics::new(module_id);
416
417    let inference_id = InferenceId::LookupItemDeclaration(lookup_item_id);
418
419    let resolver = match parent_resolver_data {
420        Some(parent_resolver_data) => {
421            Resolver::with_data(db, parent_resolver_data.clone_with_inference_id(db, inference_id))
422        }
423        None => Resolver::new(db, module_id, inference_id),
424    };
425
426    let resolver_data = Arc::new(resolver.data);
427
428    let diagnostic_added =
429        diagnostics.report(constant_ast.stable_ptr(db), SemanticDiagnosticKind::ConstCycle);
430    Ok(ConstantData {
431        constant: Err(diagnostic_added),
432        const_value: ConstValue::Missing(diagnostic_added).intern(db),
433        diagnostics: diagnostics.build(),
434        resolver_data,
435    })
436}
437
438/// Checks if the given expression only involved constant calculations.
439pub fn validate_const_expr<'db>(ctx: &mut ComputationContext<'db, '_>, expr_id: ExprId) {
440    let info = ctx.db.const_calc_info();
441    let mut eval_ctx = ConstantEvaluateContext {
442        db: ctx.db,
443        info: info.as_ref(),
444        arenas: &ctx.arenas,
445        vars: Default::default(),
446        generic_substitution: Default::default(),
447        depth: 0,
448        diagnostics: ctx.diagnostics,
449    };
450    eval_ctx.validate(expr_id);
451}
452
453/// Resolves the given const expression and evaluates its value.
454pub fn resolve_const_expr_and_evaluate<'db, 'mt>(
455    db: &'db dyn Database,
456    ctx: &'mt mut ComputationContext<'db, '_>,
457    value: &ExprAndId<'db>,
458    const_stable_ptr: SyntaxStablePtrId<'db>,
459    target_type: TypeId<'db>,
460    finalize: bool,
461) -> ConstValueId<'db> {
462    let prev_err_count = ctx.diagnostics.error_count;
463    let mut_ref = &mut ctx.resolver;
464    let mut inference: crate::expr::inference::Inference<'db, '_> = mut_ref.inference();
465    if let Err(err_set) = inference.conform_ty(value.ty(), target_type) {
466        inference.report_on_pending_error(err_set, ctx.diagnostics, const_stable_ptr);
467    }
468
469    if finalize {
470        // Check fully resolved.
471        inference.finalize(ctx.diagnostics, const_stable_ptr);
472    } else if let Err(err_set) = inference.solve() {
473        inference.report_on_pending_error(err_set, ctx.diagnostics, const_stable_ptr);
474    }
475
476    // TODO(orizi): Consider moving this to be called only upon creating const values, other callees
477    // don't necessarily need it.
478    ctx.apply_inference_rewriter_to_exprs();
479
480    match &value.expr {
481        Expr::Constant(ExprConstant { const_value_id, .. }) => *const_value_id,
482        // Check that the expression is a valid constant.
483        _ if ctx.diagnostics.error_count > prev_err_count => {
484            ConstValue::Missing(skip_diagnostic()).intern(db)
485        }
486        _ => {
487            let info = db.const_calc_info();
488            let mut eval_ctx = ConstantEvaluateContext {
489                db,
490                info: info.as_ref(),
491                arenas: &ctx.arenas,
492                vars: Default::default(),
493                generic_substitution: Default::default(),
494                depth: 0,
495                diagnostics: ctx.diagnostics,
496            };
497            eval_ctx.validate(value.id);
498            if eval_ctx.diagnostics.error_count > prev_err_count {
499                ConstValue::Missing(skip_diagnostic()).intern(db)
500            } else {
501                eval_ctx.evaluate(value.id)
502            }
503        }
504    }
505}
506
507/// A context for evaluating constant expressions.
508struct ConstantEvaluateContext<'a, 'r, 'mt> {
509    db: &'a dyn Database,
510    info: &'r ConstCalcInfo<'a>,
511    arenas: &'r Arenas<'a>,
512    vars: OrderedHashMap<VarId<'a>, ConstValueId<'a>>,
513    generic_substitution: GenericSubstitution<'a>,
514    depth: usize,
515    diagnostics: &'mt mut SemanticDiagnostics<'a>,
516}
517impl<'a, 'r, 'mt> ConstantEvaluateContext<'a, 'r, 'mt> {
518    /// Validate the given expression can be used as constant.
519    fn validate(&mut self, expr_id: ExprId) {
520        match &self.arenas.exprs[expr_id] {
521            Expr::Var(_) | Expr::Constant(_) | Expr::Missing(_) => {}
522            Expr::Block(ExprBlock { statements, tail: Some(inner), .. }) => {
523                for statement_id in statements {
524                    match &self.arenas.statements[*statement_id] {
525                        Statement::Let(statement) => {
526                            self.validate(statement.expr);
527                        }
528                        Statement::Expr(expr) => {
529                            self.validate(expr.expr);
530                        }
531                        other => {
532                            self.diagnostics.report(
533                                other.stable_ptr(),
534                                SemanticDiagnosticKind::UnsupportedConstant,
535                            );
536                        }
537                    }
538                }
539                self.validate(*inner);
540            }
541            Expr::FunctionCall(expr) => {
542                for arg in &expr.args {
543                    match arg {
544                        ExprFunctionCallArg::Value(arg) => self.validate(*arg),
545                        ExprFunctionCallArg::Reference(var) => {
546                            self.diagnostics.report(
547                                var.stable_ptr(),
548                                SemanticDiagnosticKind::UnsupportedConstant,
549                            );
550                        }
551                        ExprFunctionCallArg::TempReference(expr_id) => {
552                            self.diagnostics.report(
553                                self.arenas.exprs[*expr_id].stable_ptr(),
554                                SemanticDiagnosticKind::UnsupportedConstant,
555                            );
556                        }
557                    }
558                }
559                if !self.is_function_const(expr.function) {
560                    self.diagnostics.report(
561                        expr.stable_ptr.untyped(),
562                        SemanticDiagnosticKind::UnsupportedConstant,
563                    );
564                }
565            }
566            Expr::Literal(expr) => {
567                if let Err(err) = validate_literal(self.db, expr.ty, &expr.value) {
568                    self.diagnostics.report(
569                        expr.stable_ptr.untyped(),
570                        SemanticDiagnosticKind::LiteralError(err),
571                    );
572                }
573            }
574            Expr::Tuple(expr) => {
575                for item in &expr.items {
576                    self.validate(*item);
577                }
578            }
579            Expr::StructCtor(ExprStructCtor { members, base_struct: None, .. }) => {
580                for (expr_id, _) in members {
581                    self.validate(*expr_id);
582                }
583            }
584            Expr::EnumVariantCtor(expr) => self.validate(expr.value_expr),
585            Expr::MemberAccess(expr) => self.validate(expr.expr),
586            Expr::FixedSizeArray(expr) => match &expr.items {
587                crate::FixedSizeArrayItems::Items(items) => {
588                    for item in items {
589                        self.validate(*item);
590                    }
591                }
592                crate::FixedSizeArrayItems::ValueAndSize(value, _) => {
593                    self.validate(*value);
594                }
595            },
596            Expr::Snapshot(expr) => self.validate(expr.inner),
597            Expr::Desnap(expr) => self.validate(expr.inner),
598            Expr::LogicalOperator(expr) => {
599                self.validate(expr.lhs);
600                self.validate(expr.rhs);
601            }
602            Expr::Match(expr) => {
603                self.validate(expr.matched_expr);
604                for arm in &expr.arms {
605                    self.validate(arm.expression);
606                }
607            }
608            Expr::If(expr) => {
609                for condition in &expr.conditions {
610                    self.validate(match condition {
611                        Condition::BoolExpr(id) | Condition::Let(id, _) => *id,
612                    });
613                }
614                self.validate(expr.if_block);
615                if let Some(else_block) = expr.else_block {
616                    self.validate(else_block);
617                }
618            }
619            other => {
620                self.diagnostics.report(
621                    other.stable_ptr().untyped(),
622                    SemanticDiagnosticKind::UnsupportedConstant,
623                );
624            }
625        }
626    }
627
628    /// Returns true if the given function is allowed to be called in constant context.
629    fn is_function_const(&self, function_id: FunctionId<'a>) -> bool {
630        if function_id == self.panic_with_felt252 {
631            return true;
632        }
633        let db = self.db;
634        let concrete_function = function_id.get_concrete(db);
635        let signature = (|| match concrete_function.generic_function {
636            GenericFunctionId::Free(id) => db.free_function_signature(id),
637            GenericFunctionId::Extern(id) => db.extern_function_signature(id),
638            GenericFunctionId::Impl(id) => {
639                if let ImplLongId::Concrete(impl_id) = id.impl_id.long(db)
640                    && let Ok(Some(impl_function_id)) = impl_id.get_impl_function(db, id.function)
641                {
642                    return self.db.impl_function_signature(impl_function_id);
643                }
644                self.db.trait_function_signature(id.function)
645            }
646        })();
647        if signature.map(|s| s.is_const) == Ok(true) {
648            return true;
649        }
650        let Ok(Some(body)) = concrete_function.body(db) else { return false };
651        let GenericFunctionWithBodyId::Impl(imp) = body.generic_function(db) else {
652            return false;
653        };
654        let impl_def = imp.concrete_impl_id.impl_def_id(db);
655        if impl_def.parent_module(db).owning_crate(db) != db.core_crate() {
656            return false;
657        }
658        let Ok(trait_id) = db.impl_def_trait(impl_def) else {
659            return false;
660        };
661        self.const_traits.contains(&trait_id)
662    }
663
664    /// Evaluate the given const expression value.
665    fn evaluate<'ctx>(&'ctx mut self, expr_id: ExprId) -> ConstValueId<'a> {
666        let expr = &self.arenas.exprs[expr_id];
667        let db = self.db;
668        let to_missing = |diag_added| ConstValue::Missing(diag_added).intern(db);
669        match expr {
670            Expr::Var(expr) => self.vars.get(&expr.var).copied().unwrap_or_else(|| {
671                to_missing(
672                    self.diagnostics
673                        .report(expr.stable_ptr, SemanticDiagnosticKind::UnsupportedConstant),
674                )
675            }),
676            Expr::Constant(expr) => self
677                .generic_substitution
678                .substitute(self.db, expr.const_value_id)
679                .unwrap_or_else(to_missing),
680            Expr::Block(ExprBlock { statements, tail: Some(inner), .. }) => {
681                for statement_id in statements {
682                    match &self.arenas.statements[*statement_id] {
683                        Statement::Let(statement) => {
684                            let value = self.evaluate(statement.expr);
685                            self.destructure_pattern(statement.pattern, value);
686                        }
687                        Statement::Expr(expr) => {
688                            self.evaluate(expr.expr);
689                        }
690                        other => {
691                            self.diagnostics.report(
692                                other.stable_ptr(),
693                                SemanticDiagnosticKind::UnsupportedConstant,
694                            );
695                        }
696                    }
697                }
698                self.evaluate(*inner)
699            }
700            Expr::FunctionCall(expr) => self.evaluate_function_call(expr),
701            Expr::Literal(expr) => ConstValueId::from_int(db, expr.ty, &expr.value),
702            Expr::Tuple(expr) => ConstValue::Struct(
703                expr.items.iter().map(|expr_id| self.evaluate(*expr_id)).collect(),
704                expr.ty,
705            )
706            .intern(db),
707            Expr::StructCtor(ExprStructCtor {
708                members,
709                base_struct: None,
710                ty,
711                concrete_struct_id,
712                ..
713            }) => {
714                let member_order = match db.concrete_struct_members(*concrete_struct_id) {
715                    Ok(member_order) => member_order,
716                    Err(diag_add) => return to_missing(diag_add),
717                };
718                ConstValue::Struct(
719                    member_order
720                        .values()
721                        .map(|m| {
722                            members
723                                .iter()
724                                .find(|(_, member_id)| m.id == *member_id)
725                                .map(|(expr_id, _)| self.evaluate(*expr_id))
726                                .expect("Should have been caught by semantic validation")
727                        })
728                        .collect(),
729                    *ty,
730                )
731                .intern(db)
732            }
733            Expr::EnumVariantCtor(expr) => {
734                ConstValue::Enum(expr.variant, self.evaluate(expr.value_expr)).intern(db)
735            }
736            Expr::MemberAccess(expr) => {
737                self.evaluate_member_access(expr).unwrap_or_else(to_missing)
738            }
739            Expr::FixedSizeArray(expr) => ConstValue::Struct(
740                match &expr.items {
741                    crate::FixedSizeArrayItems::Items(items) => {
742                        items.iter().map(|expr_id| self.evaluate(*expr_id)).collect()
743                    }
744                    crate::FixedSizeArrayItems::ValueAndSize(value, count) => {
745                        let value = self.evaluate(*value);
746                        if let Some(count) = count.long(db).to_int() {
747                            vec![value; count.to_usize().unwrap()]
748                        } else {
749                            self.diagnostics.report(
750                                expr.stable_ptr.untyped(),
751                                SemanticDiagnosticKind::UnsupportedConstant,
752                            );
753                            vec![]
754                        }
755                    }
756                },
757                expr.ty,
758            )
759            .intern(db),
760            Expr::Snapshot(expr) => self.evaluate(expr.inner),
761            Expr::Desnap(expr) => self.evaluate(expr.inner),
762            Expr::LogicalOperator(expr) => {
763                let lhs = self.evaluate(expr.lhs);
764                if let ConstValue::Enum(v, _) = lhs.long(db) {
765                    let early_return_variant = match expr.op {
766                        LogicalOperator::AndAnd => false_variant(self.db),
767                        LogicalOperator::OrOr => true_variant(self.db),
768                    };
769                    if *v == early_return_variant { lhs } else { self.evaluate(expr.rhs) }
770                } else {
771                    to_missing(skip_diagnostic())
772                }
773            }
774            Expr::Match(expr) => {
775                let value = self.evaluate(expr.matched_expr);
776                let ConstValue::Enum(variant, value) = value.long(db) else {
777                    return to_missing(skip_diagnostic());
778                };
779                for arm in &expr.arms {
780                    for pattern_id in &arm.patterns {
781                        let pattern = &self.arenas.patterns[*pattern_id];
782                        if matches!(pattern, Pattern::Otherwise(_)) {
783                            return self.evaluate(arm.expression);
784                        }
785                        let Pattern::EnumVariant(pattern) = pattern else {
786                            continue;
787                        };
788                        if pattern.variant.idx != variant.idx {
789                            continue;
790                        }
791                        if let Some(inner_pattern) = pattern.inner_pattern {
792                            self.destructure_pattern(inner_pattern, *value);
793                        }
794                        return self.evaluate(arm.expression);
795                    }
796                }
797                to_missing(
798                    self.diagnostics.report(
799                        expr.stable_ptr.untyped(),
800                        SemanticDiagnosticKind::UnsupportedConstant,
801                    ),
802                )
803            }
804            Expr::If(expr) => {
805                let mut if_condition: bool = true;
806                for condition in &expr.conditions {
807                    match condition {
808                        crate::Condition::BoolExpr(id) => {
809                            let condition = self.evaluate(*id);
810                            let ConstValue::Enum(variant, _) = condition.long(db) else {
811                                return to_missing(skip_diagnostic());
812                            };
813                            if *variant != true_variant(self.db) {
814                                if_condition = false;
815                                break;
816                            }
817                        }
818                        crate::Condition::Let(id, patterns) => {
819                            let value = self.evaluate(*id);
820                            let ConstValue::Enum(variant, value) = value.long(db) else {
821                                return to_missing(skip_diagnostic());
822                            };
823                            let mut found_pattern = false;
824                            for pattern_id in patterns {
825                                let Pattern::EnumVariant(pattern) =
826                                    &self.arenas.patterns[*pattern_id]
827                                else {
828                                    continue;
829                                };
830                                if pattern.variant != *variant {
831                                    // Continue to the next option in the `|` list.
832                                    continue;
833                                }
834                                if let Some(inner_pattern) = pattern.inner_pattern {
835                                    self.destructure_pattern(inner_pattern, *value);
836                                }
837                                found_pattern = true;
838                                break;
839                            }
840                            if !found_pattern {
841                                if_condition = false;
842                                break;
843                            }
844                        }
845                    }
846                }
847
848                if if_condition {
849                    self.evaluate(expr.if_block)
850                } else if let Some(else_block) = expr.else_block {
851                    self.evaluate(else_block)
852                } else {
853                    self.unit_const
854                }
855            }
856            _ => to_missing(skip_diagnostic()),
857        }
858    }
859
860    /// Attempts to evaluate constants from a const function call.
861    fn evaluate_function_call(&mut self, expr: &ExprFunctionCall<'a>) -> ConstValueId<'a> {
862        let db = self.db;
863        let to_missing = |diag_added| ConstValue::Missing(diag_added).intern(db);
864        let args = expr
865            .args
866            .iter()
867            .filter_map(|arg| try_extract_matches!(arg, ExprFunctionCallArg::Value))
868            .map(|arg| self.evaluate(*arg))
869            .collect_vec();
870        if expr.function == self.panic_with_felt252 {
871            return to_missing(self.diagnostics.report(
872                expr.stable_ptr.untyped(),
873                SemanticDiagnosticKind::FailedConstantCalculation,
874            ));
875        }
876        let concrete_function =
877            match self.generic_substitution.substitute(db, expr.function.get_concrete(db)) {
878                Ok(v) => v,
879                Err(err) => return to_missing(err),
880            };
881        if let Some(calc_result) =
882            self.evaluate_const_function_call(&concrete_function, &args, expr)
883        {
884            return calc_result;
885        }
886
887        let imp = extract_matches!(concrete_function.generic_function, GenericFunctionId::Impl);
888        let bool_value = |condition: bool| {
889            if condition { self.true_const } else { self.false_const }
890        };
891
892        if imp.function == self.eq_fn {
893            return bool_value(args[0] == args[1]);
894        } else if imp.function == self.ne_fn {
895            return bool_value(args[0] != args[1]);
896        } else if imp.function == self.not_fn {
897            return bool_value(args[0] == self.false_const);
898        }
899
900        let args = match args
901            .into_iter()
902            .map(|arg| NumericArg::try_new(db, arg))
903            .collect::<Option<Vec<_>>>()
904        {
905            Some(args) => args,
906            // Diagnostic can be skipped as we would either have a semantic error for a bad arg for
907            // the function, or the arg itself couldn't have been calculated.
908            None => return to_missing(skip_diagnostic()),
909        };
910        let value = match imp.function {
911            id if id == self.neg_fn => -&args[0].v,
912            id if id == self.add_fn => &args[0].v + &args[1].v,
913            id if id == self.sub_fn => &args[0].v - &args[1].v,
914            id if id == self.mul_fn => &args[0].v * &args[1].v,
915            id if (id == self.div_fn || id == self.rem_fn) && args[1].v.is_zero() => {
916                return to_missing(
917                    self.diagnostics
918                        .report(expr.stable_ptr.untyped(), SemanticDiagnosticKind::DivisionByZero),
919                );
920            }
921            id if id == self.div_fn => &args[0].v / &args[1].v,
922            id if id == self.rem_fn => &args[0].v % &args[1].v,
923            id if id == self.bitand_fn => &args[0].v & &args[1].v,
924            id if id == self.bitor_fn => &args[0].v | &args[1].v,
925            id if id == self.bitxor_fn => &args[0].v ^ &args[1].v,
926            id if id == self.lt_fn => return bool_value(args[0].v < args[1].v),
927            id if id == self.le_fn => return bool_value(args[0].v <= args[1].v),
928            id if id == self.gt_fn => return bool_value(args[0].v > args[1].v),
929            id if id == self.ge_fn => return bool_value(args[0].v >= args[1].v),
930            id if id == self.div_rem_fn => {
931                // No need for non-zero check as this is type checked to begin with.
932                // Also results are always in the range of the input type, so `unwrap`s are ok.
933                return ConstValue::Struct(
934                    vec![
935                        ConstValueId::from_int(db, args[0].ty, &(&args[0].v / &args[1].v)),
936                        ConstValueId::from_int(db, args[0].ty, &(&args[0].v % &args[1].v)),
937                    ],
938                    expr.ty,
939                )
940                .intern(db);
941            }
942            _ => {
943                unreachable!("Unexpected function call in constant lowering: {:?}", expr)
944            }
945        };
946        if expr.ty == self.felt252 {
947            ConstValue::Int(canonical_felt252(&value), expr.ty).intern(db)
948        } else if let Err(err) = validate_literal(db, expr.ty, &value) {
949            to_missing(
950                self.diagnostics
951                    .report(expr.stable_ptr.untyped(), SemanticDiagnosticKind::LiteralError(err)),
952            )
953        } else {
954            ConstValueId::from_int(db, expr.ty, &value)
955        }
956    }
957
958    /// Attempts to evaluate a constant function call.
959    fn evaluate_const_function_call(
960        &mut self,
961        concrete_function: &ConcreteFunction<'a>,
962        args: &[ConstValueId<'a>],
963        expr: &ExprFunctionCall<'a>,
964    ) -> Option<ConstValueId<'a>> {
965        let db = self.db;
966        if let GenericFunctionId::Extern(extern_fn) = concrete_function.generic_function {
967            let expr_ty = self.generic_substitution.substitute(db, expr.ty).ok()?;
968            if self.upcast_fns.contains(&extern_fn) {
969                let [arg] = args else { return None };
970                return Some(ConstValueId::from_int(db, expr_ty, arg.long(db).to_int()?));
971            } else if self.unwrap_non_zero == extern_fn {
972                let [arg] = args else { return None };
973                return try_extract_matches!(arg.long(db), ConstValue::NonZero).copied();
974            } else if self.u128s_from_felt252 == extern_fn {
975                let [arg] = args else { return None };
976                let TypeLongId::Concrete(ConcreteTypeId::Enum(enm)) = expr_ty.long(db) else {
977                    return None;
978                };
979                let (narrow, wide) =
980                    db.concrete_enum_variants(*enm).ok()?.into_iter().collect_tuple()?;
981                let value = felt252_for_downcast(arg.long(db).to_int()?, &BigInt::ZERO);
982                let mask128 = BigInt::from(u128::MAX);
983                let low = (&value) & mask128;
984                let high: BigInt = (&value) >> 128;
985                return Some(if high.is_zero() {
986                    ConstValue::Enum(narrow, ConstValue::Int(low, narrow.ty).intern(db)).intern(db)
987                } else {
988                    ConstValue::Enum(
989                        wide,
990                        ConstValue::Struct(
991                            vec![
992                                (ConstValue::Int(high, self.u128).intern(db)),
993                                (ConstValue::Int(low, self.u128).intern(db)),
994                            ],
995                            wide.ty,
996                        )
997                        .intern(db),
998                    )
999                    .intern(db)
1000                });
1001            } else if let Some(reversed) = self.downcast_fns.get(&extern_fn) {
1002                let [arg] = args else { return None };
1003                let ConstValue::Int(value, input_ty) = arg.long(db) else { return None };
1004                let TypeLongId::Concrete(ConcreteTypeId::Enum(enm)) = expr_ty.long(db) else {
1005                    return None;
1006                };
1007                let (variant0, variant1) =
1008                    db.concrete_enum_variants(*enm).ok()?.into_iter().collect_tuple()?;
1009                let (some, none) =
1010                    if *reversed { (variant1, variant0) } else { (variant0, variant1) };
1011                let success_ty = some.ty;
1012                let out_range = self
1013                    .type_value_ranges
1014                    .get(&success_ty)
1015                    .cloned()
1016                    .or_else(|| {
1017                        let (min, max) = try_extract_bounded_int_type_ranges(db, success_ty)?;
1018                        Some(TypeRange::new(min, max))
1019                    })
1020                    .unwrap_or_else(|| {
1021                        unreachable!(
1022                            "`downcast` is only allowed into types that can be literals. Got `{}`.",
1023                            success_ty.format(db)
1024                        )
1025                    });
1026                let value = if *input_ty == self.felt252 {
1027                    felt252_for_downcast(value, &out_range.min)
1028                } else {
1029                    value.clone()
1030                };
1031                return Some(if value >= out_range.min && value <= out_range.max {
1032                    ConstValue::Enum(some, ConstValue::Int(value, success_ty).intern(db)).intern(db)
1033                } else {
1034                    ConstValue::Enum(none, self.unit_const).intern(db)
1035                });
1036            } else if self.nz_fns.contains(&extern_fn) {
1037                let [arg] = args else { return None };
1038                let (ty, is_zero) = match arg.long(db) {
1039                    ConstValue::Int(val, ty) => (ty, val.is_zero()),
1040                    ConstValue::Struct(members, ty) => (
1041                        ty,
1042                        // For u256 struct with (low, high), check if both are zero
1043                        members.iter().all(|member| match member.long(db) {
1044                            ConstValue::Int(val, _) => val.is_zero(),
1045                            _ => false,
1046                        }),
1047                    ),
1048                    _ => unreachable!(
1049                        "`is_zero` is only allowed for integers got `{}`",
1050                        arg.ty(db).unwrap().format(db)
1051                    ),
1052                };
1053
1054                return Some(
1055                    if is_zero {
1056                        ConstValue::Enum(
1057                            crate::corelib::jump_nz_zero_variant(db, *ty),
1058                            self.unit_const,
1059                        )
1060                    } else {
1061                        ConstValue::Enum(
1062                            crate::corelib::jump_nz_nonzero_variant(db, *ty),
1063                            ConstValue::NonZero(*arg).intern(db),
1064                        )
1065                    }
1066                    .intern(db),
1067                );
1068            } else {
1069                unreachable!(
1070                    "Unexpected extern function in constant lowering: `{}`",
1071                    extern_fn.full_path(db)
1072                );
1073            }
1074        }
1075        let body_id = concrete_function.body(db).ok()??;
1076        let concrete_body_id = body_id.function_with_body_id(db);
1077        let signature = db.function_with_body_signature(concrete_body_id).ok()?;
1078        require(signature.is_const)?;
1079        let generic_substitution = body_id.substitution(db).ok()?;
1080        let body = db.function_body(concrete_body_id).ok()?;
1081        const MAX_CONST_EVAL_DEPTH: usize = 100;
1082        if self.depth > MAX_CONST_EVAL_DEPTH {
1083            return Some(
1084                ConstValue::Missing(self.diagnostics.report(
1085                    expr.stable_ptr,
1086                    SemanticDiagnosticKind::ConstantCalculationDepthExceeded,
1087                ))
1088                .intern(db),
1089            );
1090        }
1091        let mut diagnostics = SemanticDiagnostics::new(concrete_body_id.parent_module(db));
1092        let mut inner = ConstantEvaluateContext {
1093            db,
1094            info: self.info,
1095            arenas: &body.arenas,
1096            vars: signature
1097                .params
1098                .iter()
1099                .map(|p| VarId::Param(p.id))
1100                .zip(args.iter().cloned())
1101                .collect(),
1102            generic_substitution,
1103            depth: self.depth + 1,
1104            diagnostics: &mut diagnostics,
1105        };
1106        let value = inner.evaluate(body.body_expr);
1107        for diagnostic in diagnostics.build().get_all() {
1108            let location = diagnostic.location(db);
1109            let (inner_diag, mut notes) = match diagnostic.kind {
1110                SemanticDiagnosticKind::ConstantCalculationDepthExceeded => {
1111                    self.diagnostics.report(
1112                        expr.stable_ptr,
1113                        SemanticDiagnosticKind::ConstantCalculationDepthExceeded,
1114                    );
1115                    continue;
1116                }
1117                SemanticDiagnosticKind::InnerFailedConstantCalculation(inner_diag, notes) => {
1118                    (inner_diag, notes)
1119                }
1120                _ => (diagnostic.into(), vec![]),
1121            };
1122            notes.push(DiagnosticNote::with_location(
1123                format!("In `{}`", concrete_function.full_path(db)),
1124                location,
1125            ));
1126            self.diagnostics.report(
1127                expr.stable_ptr,
1128                SemanticDiagnosticKind::InnerFailedConstantCalculation(inner_diag, notes),
1129            );
1130        }
1131        Some(value)
1132    }
1133
1134    /// Extract const member access from a const value.
1135    fn evaluate_member_access(&mut self, expr: &ExprMemberAccess<'a>) -> Maybe<ConstValueId<'a>> {
1136        let full_struct = self.evaluate(expr.expr);
1137        let ConstValue::Struct(values, _) = full_struct.long(self.db) else {
1138            // A semantic diagnostic should have been reported.
1139            return Err(skip_diagnostic());
1140        };
1141        let members = self.db.concrete_struct_members(expr.concrete_struct_id)?;
1142        let Some(member_idx) = members.iter().position(|(_, member)| member.id == expr.member)
1143        else {
1144            // A semantic diagnostic should have been reported.
1145            return Err(skip_diagnostic());
1146        };
1147        Ok(values[member_idx])
1148    }
1149
1150    /// Destructures the pattern into the const value of the variables in scope.
1151    fn destructure_pattern(&mut self, pattern_id: PatternId, value: ConstValueId<'a>) {
1152        let pattern = &self.arenas.patterns[pattern_id];
1153        let db = self.db;
1154        match pattern {
1155            Pattern::Literal(_)
1156            | Pattern::StringLiteral(_)
1157            | Pattern::Otherwise(_)
1158            | Pattern::Missing(_) => {}
1159            Pattern::Variable(pattern) => {
1160                self.vars.insert(VarId::Local(pattern.var.id), value);
1161            }
1162            Pattern::Struct(pattern) => {
1163                if let ConstValue::Struct(inner_values, _) = value.long(db) {
1164                    let member_order = match db.concrete_struct_members(pattern.concrete_struct_id)
1165                    {
1166                        Ok(member_order) => member_order,
1167                        Err(_) => return,
1168                    };
1169                    for (member, inner_value) in zip(member_order.values(), inner_values) {
1170                        if let Some((inner_pattern, _)) =
1171                            pattern.field_patterns.iter().find(|(_, field)| member.id == field.id)
1172                        {
1173                            self.destructure_pattern(*inner_pattern, *inner_value);
1174                        }
1175                    }
1176                }
1177            }
1178            Pattern::Tuple(pattern) => {
1179                if let ConstValue::Struct(inner_values, _) = value.long(db) {
1180                    for (inner_pattern, inner_value) in zip(&pattern.field_patterns, inner_values) {
1181                        self.destructure_pattern(*inner_pattern, *inner_value);
1182                    }
1183                }
1184            }
1185            Pattern::FixedSizeArray(pattern) => {
1186                if let ConstValue::Struct(inner_values, _) = value.long(db) {
1187                    for (inner_pattern, inner_value) in
1188                        zip(&pattern.elements_patterns, inner_values)
1189                    {
1190                        self.destructure_pattern(*inner_pattern, *inner_value);
1191                    }
1192                }
1193            }
1194            Pattern::EnumVariant(pattern) => {
1195                if let ConstValue::Enum(variant, inner_value) = value.long(db)
1196                    && pattern.variant == *variant
1197                    && let Some(inner_pattern) = pattern.inner_pattern
1198                {
1199                    self.destructure_pattern(inner_pattern, *inner_value);
1200                }
1201            }
1202        }
1203    }
1204}
1205
1206impl<'db, 'r> std::ops::Deref for ConstantEvaluateContext<'db, 'r, '_> {
1207    type Target = ConstCalcInfo<'db>;
1208    fn deref(&self) -> &Self::Target {
1209        self.info
1210    }
1211}
1212
1213/// Helper for the arguments info.
1214struct NumericArg<'db> {
1215    /// The arg's integer value.
1216    v: BigInt,
1217    /// The arg's type.
1218    ty: TypeId<'db>,
1219}
1220impl<'db> NumericArg<'db> {
1221    fn try_new(db: &'db dyn Database, arg: ConstValueId<'db>) -> Option<Self> {
1222        Some(Self { ty: arg.ty(db).ok()?, v: numeric_arg_value(db, arg)? })
1223    }
1224}
1225
1226/// Helper for creating a `NumericArg` value.
1227/// This includes unwrapping of `NonZero` values and struct of 2 values as a `u256`.
1228fn numeric_arg_value<'db>(db: &'db dyn Database, value: ConstValueId<'db>) -> Option<BigInt> {
1229    match value.long(db) {
1230        ConstValue::Int(value, _) => Some(value.clone()),
1231        ConstValue::Struct(v, _) => {
1232            if let [low, high] = &v[..] {
1233                Some(low.long(db).to_int()? + (high.long(db).to_int()? << 128))
1234            } else {
1235                None
1236            }
1237        }
1238        ConstValue::NonZero(const_value) => numeric_arg_value(db, *const_value),
1239        _ => None,
1240    }
1241}
1242
1243/// Query implementation of [ConstantSemantic::const_calc_info].
1244fn const_calc_info<'db>(db: &'db dyn Database) -> Arc<ConstCalcInfo<'db>> {
1245    Arc::new(ConstCalcInfo::new(db))
1246}
1247
1248/// Implementation of [ConstantSemantic::const_calc_info].
1249#[salsa::tracked]
1250fn const_calc_info_tracked<'db>(db: &'db dyn Database) -> Arc<ConstCalcInfo<'db>> {
1251    const_calc_info(db)
1252}
1253
1254/// Holds static information about extern functions required for const calculations.
1255#[derive(Debug, PartialEq, Eq, salsa::Update)]
1256pub struct ConstCalcInfo<'db> {
1257    /// Traits that are allowed for consts if their impls is in the corelib.
1258    const_traits: UnorderedHashSet<TraitId<'db>>,
1259    /// The const value for the unit type `()`.
1260    unit_const: ConstValueId<'db>,
1261    /// The const value for `true`.
1262    true_const: ConstValueId<'db>,
1263    /// The const value for `false`.
1264    false_const: ConstValueId<'db>,
1265    /// The function for panicking with a felt252.
1266    panic_with_felt252: FunctionId<'db>,
1267    /// The integer `upcast` style functions.
1268    pub upcast_fns: UnorderedHashSet<ExternFunctionId<'db>>,
1269    /// The integer `downcast` style functions, mapping to whether it returns a reversed Option
1270    /// enum.
1271    pub downcast_fns: UnorderedHashMap<ExternFunctionId<'db>, bool>,
1272    /// The `felt252` into `u128` words libfunc.
1273    pub u128s_from_felt252: ExternFunctionId<'db>,
1274    /// The `unwrap_non_zero` function.
1275    unwrap_non_zero: ExternFunctionId<'db>,
1276    /// The `is_zero` style functions.
1277    pub nz_fns: UnorderedHashSet<ExternFunctionId<'db>>,
1278    /// The range of values of a numeric type.
1279    pub type_value_ranges: UnorderedHashMap<TypeId<'db>, TypeRange>,
1280
1281    core_info: Arc<CoreInfo<'db>>,
1282}
1283
1284impl<'db> std::ops::Deref for ConstCalcInfo<'db> {
1285    type Target = CoreInfo<'db>;
1286    fn deref(&self) -> &CoreInfo<'db> {
1287        &self.core_info
1288    }
1289}
1290
1291impl<'db> ConstCalcInfo<'db> {
1292    /// Creates a new ConstCalcInfo.
1293    fn new(db: &'db dyn Database) -> Self {
1294        let core_info = db.core_info();
1295        let unit_const = ConstValue::Struct(vec![], unit_ty(db)).intern(db);
1296        let core = ModuleHelper::core(db);
1297        let bounded_int = core.submodule("internal").submodule("bounded_int");
1298        let integer = core.submodule("integer");
1299        let zeroable = core.submodule("zeroable");
1300        let starknet = core.submodule("starknet");
1301        let class_hash_module = starknet.submodule("class_hash");
1302        let class_hash_ty = class_hash_module.ty("ClassHash", vec![]);
1303        let contract_address_module = starknet.submodule("contract_address");
1304        let contract_address_ty = contract_address_module.ty("ContractAddress", vec![]);
1305        Self {
1306            const_traits: FromIterator::from_iter([
1307                core_info.neg_trt,
1308                core_info.add_trt,
1309                core_info.sub_trt,
1310                core_info.mul_trt,
1311                core_info.div_trt,
1312                core_info.rem_trt,
1313                core_info.div_rem_trt,
1314                core_info.bitand_trt,
1315                core_info.bitor_trt,
1316                core_info.bitxor_trt,
1317                core_info.partialeq_trt,
1318                core_info.partialord_trt,
1319                core_info.not_trt,
1320            ]),
1321            true_const: ConstValue::Enum(true_variant(db), unit_const).intern(db),
1322            false_const: ConstValue::Enum(false_variant(db), unit_const).intern(db),
1323            unit_const,
1324            panic_with_felt252: core.function_id("panic_with_felt252", vec![]),
1325            upcast_fns: FromIterator::from_iter([
1326                bounded_int.extern_function_id("upcast"),
1327                integer.extern_function_id("u8_to_felt252"),
1328                integer.extern_function_id("u16_to_felt252"),
1329                integer.extern_function_id("u32_to_felt252"),
1330                integer.extern_function_id("u64_to_felt252"),
1331                integer.extern_function_id("u128_to_felt252"),
1332                integer.extern_function_id("i8_to_felt252"),
1333                integer.extern_function_id("i16_to_felt252"),
1334                integer.extern_function_id("i32_to_felt252"),
1335                integer.extern_function_id("i64_to_felt252"),
1336                integer.extern_function_id("i128_to_felt252"),
1337                class_hash_module.extern_function_id("class_hash_to_felt252"),
1338                contract_address_module.extern_function_id("contract_address_to_felt252"),
1339            ]),
1340            downcast_fns: FromIterator::from_iter([
1341                (bounded_int.extern_function_id("downcast"), false),
1342                (bounded_int.extern_function_id("bounded_int_trim_min"), true),
1343                (bounded_int.extern_function_id("bounded_int_trim_max"), true),
1344                (integer.extern_function_id("u8_try_from_felt252"), false),
1345                (integer.extern_function_id("u16_try_from_felt252"), false),
1346                (integer.extern_function_id("u32_try_from_felt252"), false),
1347                (integer.extern_function_id("u64_try_from_felt252"), false),
1348                (integer.extern_function_id("i8_try_from_felt252"), false),
1349                (integer.extern_function_id("i16_try_from_felt252"), false),
1350                (integer.extern_function_id("i32_try_from_felt252"), false),
1351                (integer.extern_function_id("i64_try_from_felt252"), false),
1352                (integer.extern_function_id("i128_try_from_felt252"), false),
1353                (class_hash_module.extern_function_id("class_hash_try_from_felt252"), false),
1354                (
1355                    contract_address_module.extern_function_id("contract_address_try_from_felt252"),
1356                    false,
1357                ),
1358            ]),
1359            u128s_from_felt252: integer.extern_function_id("u128s_from_felt252"),
1360            unwrap_non_zero: zeroable.extern_function_id("unwrap_non_zero"),
1361            nz_fns: FromIterator::from_iter([
1362                core.extern_function_id("felt252_is_zero"),
1363                bounded_int.extern_function_id("bounded_int_is_zero"),
1364                integer.extern_function_id("u8_is_zero"),
1365                integer.extern_function_id("u16_is_zero"),
1366                integer.extern_function_id("u32_is_zero"),
1367                integer.extern_function_id("u64_is_zero"),
1368                integer.extern_function_id("u128_is_zero"),
1369                integer.extern_function_id("u256_is_zero"),
1370            ]),
1371            type_value_ranges: FromIterator::from_iter([
1372                (core_info.u8, TypeRange::new(u8::MIN, u8::MAX)),
1373                (core_info.u16, TypeRange::new(u16::MIN, u16::MAX)),
1374                (core_info.u32, TypeRange::new(u32::MIN, u32::MAX)),
1375                (core_info.u64, TypeRange::new(u64::MIN, u64::MAX)),
1376                (core_info.u128, TypeRange::new(u128::MIN, u128::MAX)),
1377                (core_info.u256, TypeRange::new(BigInt::ZERO, BigInt::from(1) << 256)),
1378                (core_info.i8, TypeRange::new(i8::MIN, i8::MAX)),
1379                (core_info.i16, TypeRange::new(i16::MIN, i16::MAX)),
1380                (core_info.i32, TypeRange::new(i32::MIN, i32::MAX)),
1381                (core_info.i64, TypeRange::new(i64::MIN, i64::MAX)),
1382                (core_info.i128, TypeRange::new(i128::MIN, i128::MAX)),
1383                (class_hash_ty, TypeRange::new(BigInt::ZERO, BigInt::from(1) << 251)),
1384                (contract_address_ty, TypeRange::new(BigInt::ZERO, BigInt::from(1) << 251)),
1385            ]),
1386            core_info,
1387        }
1388    }
1389}
1390
1391/// Trait for constant-related semantic queries.
1392pub trait ConstantSemantic<'db>: Database {
1393    /// Returns the semantic diagnostics of a constant definition.
1394    fn constant_semantic_diagnostics(
1395        &'db self,
1396        const_id: ConstantId<'db>,
1397    ) -> Diagnostics<'db, SemanticDiagnostic<'db>> {
1398        let db = self.as_dyn_database();
1399        constant_semantic_data(db, const_id, false)
1400            .as_ref()
1401            .map(|data| data.diagnostics.clone())
1402            .unwrap_or_default()
1403    }
1404    /// Returns the semantic data of a constant definition.
1405    fn constant_semantic_data(&'db self, use_id: ConstantId<'db>) -> Maybe<Constant<'db>> {
1406        let db = self.as_dyn_database();
1407        constant_semantic_data(db, use_id, false).maybe_as_ref()?.constant.clone()
1408    }
1409    /// Returns the resolver data of a constant definition.
1410    fn constant_resolver_data(&'db self, use_id: ConstantId<'db>) -> Maybe<Arc<ResolverData<'db>>> {
1411        let db = self.as_dyn_database();
1412        Ok(constant_semantic_data(db, use_id, false).maybe_as_ref()?.resolver_data.clone())
1413    }
1414    /// Returns the const value of a constant definition.
1415    fn constant_const_value(&'db self, const_id: ConstantId<'db>) -> Maybe<ConstValueId<'db>> {
1416        let db = self.as_dyn_database();
1417        Ok(constant_semantic_data(db, const_id, false).maybe_as_ref()?.const_value)
1418    }
1419    /// Returns information required for const calculations.
1420    fn const_calc_info(&'db self) -> Arc<ConstCalcInfo<'db>> {
1421        const_calc_info_tracked(self.as_dyn_database())
1422    }
1423}
1424impl<'db, T: Database + ?Sized> ConstantSemantic<'db> for T {}
1425
1426/// A range of values of a numeric type.
1427#[derive(Clone, Debug, PartialEq, Eq, salsa::Update)]
1428pub struct TypeRange {
1429    /// The minimum value of the range.
1430    pub min: BigInt,
1431    /// The maximum value of the range.
1432    pub max: BigInt,
1433}
1434impl TypeRange {
1435    pub fn new(min: impl Into<BigInt>, max: impl Into<BigInt>) -> Self {
1436        Self { min: min.into(), max: max.into() }
1437    }
1438}