Analyze Subprogram Instantiation Declarations (#209)

* Parse subprogram instantiation to declaration

* Fix logic for identifier

* Make item and token public

* Check kind mismatch and resolve declaration

* revert accidentally deleted test

* Error on ambiguously instantiated subprograms

* Resolve overloaded uninstantiated subprograms

* return Err when the signature of the instantiated subprogram does not match

* Add comments

* Disallow instantiating an instantiable subprogram

* Disallow instantiating a non-instantiable subprogram

* Disallow calling an uninstantiated subprogram

* Disambiguate based on uninstantiated subprogram

* Fix: no longer always complain when instantiating a function

* Merge master aftermath

* Revert: Signature no longer contains optional generic map

* Refactor boolean to two-state enum

* Refactor: Region to GpkgRegion

* Refactor: subprogram instantiation to own function

* Revert: Use region instead of GpkgRegion

* Instantiate subprograms

* Remove debug print

* Refactor into more generic code

* Inline check_ent_is_uninstantiated_subprogram

* Fill in todos and false unreachable calls

* Add documentation

* Add more checks to subprogram instance testcase

* Set reference to the uninstantiated subprogram

* Fix: Analyze the return of a function type in the correct scope

* Add subprogram instance tests for future improvements

* Enable subprogram declarations as reference to the overloaded entity

* Add comment explaining the limitations of the current uninstantiated subprogram resolution

* Rename is_uninst* for less ambiguity

* Revert making fields public

* Revert accidental change

* Improve test case and add other ognored one

* Add copyright header

* Refactor SignatureKey to SubprogramKey

* Add uninstantiated subprograms to checked declarations

vhdl_lang/src/analysis/overloaded.rs

@@ -286,6 +286,21 @@ impl<'a> AnalyzeContext<'a> {
             return Err(EvalError::Unknown);
         }
 
+        // Disambiguate based on uninstantiated subprogram
+        ok_kind.retain(|ent| !ent.is_uninst_subprogram());
+
+        if ok_kind.len() == 1 {
+            let ent = ok_kind[0];
+            self.check_call(scope, call_pos, ent, assocs, diagnostics)?;
+            return Ok(Disambiguated::Unambiguous(ent));
+        } else if ok_kind.is_empty() {
+            diagnostics.push(Diagnostic::error(
+                call_name,
+                format!("uninstantiated subprogram {} cannot be called", call_name),
+            ));
+            return Err(EvalError::Unknown);
+        }
+
         let ok_formals = self.disambiguate_by_assoc_formals(scope, call_pos, &ok_kind, assocs)?;
 
         // Only one candidate matched actual/formal profile

vhdl_lang/src/analysis/package_instance.rs

@@ -5,24 +5,56 @@
 //! Copyright (c) 2023, Olof Kraigher [email protected]
 
 use fnv::FnvHashMap;
+use vhdl_lang::SrcPos;
 
 use super::analyze::*;
 use super::names::ResolvedName;
 use super::scope::*;
-use crate::ast::ActualPart;
 use crate::ast::AssociationElement;
 use crate::ast::Expression;
 use crate::ast::Literal;
 use crate::ast::Name;
 use crate::ast::Operator;
 use crate::ast::PackageInstantiation;
+use crate::ast::{ActualPart, MapAspect};
 use crate::data::DiagnosticHandler;
 use crate::named_entity::*;
 use crate::Diagnostic;
 use crate::NullDiagnostics;
 
 impl<'a> AnalyzeContext<'a> {
-    fn package_generic_map(
+    pub fn generic_package_instance(
+        &self,
+        scope: &Scope<'a>,
+        package_ent: EntRef<'a>,
+        unit: &mut PackageInstantiation,
+        diagnostics: &mut dyn DiagnosticHandler,
+    ) -> EvalResult<Region<'a>> {
+        let PackageInstantiation {
+            package_name,
+            generic_map,
+            ..
+        } = unit;
+
+        match self.analyze_package_instance_name(scope, package_name) {
+            Ok(package_region) => self
+                .generic_instance(
+                    package_ent,
+                    scope,
+                    &unit.ident.tree.pos,
+                    package_region,
+                    generic_map,
+                    diagnostics,
+                )
+                .map(|(region, _)| region),
+            Err(err) => {
+                diagnostics.push(err.into_non_fatal()?);
+                Err(EvalError::Unknown)
+            }
+        }
+    }
+
+    pub fn generic_map(
         &self,
         scope: &Scope<'a>,
         generics: GpkgRegion<'a>,
@@ -124,7 +156,7 @@ impl<'a> AnalyzeContext<'a> {
                             let resolved =
                                 self.name_resolve(scope, &assoc.actual.pos, name, diagnostics)?;
                             if let ResolvedName::Overloaded(des, overloaded) = resolved {
-                                let signature = target.signature().key().map(|base_type| {
+                                let signature = target.subprogram_key().map(|base_type| {
                                     mapping
                                         .get(&base_type.id())
                                         .map(|ent| ent.base())
@@ -139,7 +171,7 @@ impl<'a> AnalyzeContext<'a> {
                                             "Cannot map '{}' to subprogram generic {}{}",
                                             des,
                                             target.designator(),
-                                            signature.describe()
+                                            signature.key().describe()
                                         ),
                                     );
 
@@ -188,62 +220,50 @@ impl<'a> AnalyzeContext<'a> {
         Ok(mapping)
     }
 
-    pub fn generic_package_instance(
+    pub fn generic_instance(
         &self,
+        ent: EntRef<'a>,
         scope: &Scope<'a>,
-        package_ent: EntRef<'a>,
-        unit: &mut PackageInstantiation,
+        decl_pos: &SrcPos,
+        uninst_region: &Region<'a>,
+        generic_map: &mut Option<MapAspect>,
         diagnostics: &mut dyn DiagnosticHandler,
-    ) -> EvalResult<Region<'a>> {
-        let PackageInstantiation {
-            package_name,
-            generic_map,
-            ..
-        } = unit;
+    ) -> EvalResult<(Region<'a>, FnvHashMap<EntityId, TypeEnt>)> {
+        let nested = scope.nested().in_package_declaration();
+        let (generics, other) = uninst_region.to_package_generic();
+
+        let mapping = if let Some(generic_map) = generic_map {
+            self.generic_map(
+                &nested,
+                generics,
+                generic_map.list.items.as_mut_slice(),
+                diagnostics,
+            )?
+        } else {
+            FnvHashMap::default()
+        };
 
-        match self.analyze_package_instance_name(scope, package_name) {
-            Ok(package_region) => {
-                let nested = scope.nested().in_package_declaration();
-                let (generics, other) = package_region.to_package_generic();
-
-                let mapping = if let Some(generic_map) = generic_map {
-                    self.package_generic_map(
-                        &nested,
-                        generics,
-                        generic_map.list.items.as_mut_slice(),
-                        diagnostics,
-                    )?
-                } else {
-                    FnvHashMap::default()
-                };
-
-                for uninst in other {
-                    match self.instantiate(Some(package_ent), &mapping, uninst) {
-                        Ok(inst) => {
-                            // We ignore diagnostics here, for example when adding implicit operators EQ and NE for interface types
-                            // They can collide if there are more than one interface type that map to the same actual type
-                            nested.add(inst, &mut NullDiagnostics);
-                        }
-                        Err(err) => {
-                            let mut diag = Diagnostic::error(&unit.ident.tree.pos, err);
-                            if let Some(pos) = uninst.decl_pos() {
-                                diag.add_related(pos, "When instantiating this declaration");
-                            }
-                            diagnostics.push(diag);
-                        }
+        for uninst in other {
+            match self.instantiate(Some(ent), &mapping, uninst) {
+                Ok(inst) => {
+                    // We ignore diagnostics here, for example when adding implicit operators EQ and NE for interface types
+                    // They can collide if there are more than one interface type that map to the same actual type
+                    nested.add(inst, &mut NullDiagnostics);
+                }
+                Err(err) => {
+                    let mut diag = Diagnostic::error(decl_pos, err);
+                    if let Some(pos) = uninst.decl_pos() {
+                        diag.add_related(pos, "When instantiating this declaration");
                     }
+                    diagnostics.push(diag);
                 }
-
-                Ok(nested.into_region())
-            }
-            Err(err) => {
-                diagnostics.push(err.into_non_fatal()?);
-                Err(EvalError::Unknown)
             }
         }
+
+        Ok((nested.into_region(), mapping))
     }
 
-    fn instantiate(
+    pub(crate) fn instantiate(
         &self,
         parent: Option<EntRef<'a>>,
         mapping: &FnvHashMap<EntityId, TypeEnt<'a>>,
@@ -358,6 +378,16 @@ impl<'a> AnalyzeContext<'a> {
             Overloaded::Subprogram(signature) => {
                 Overloaded::Subprogram(self.map_signature(parent, mapping, signature)?)
             }
+            Overloaded::UninstSubprogramDecl(signature, generic_map) => {
+                Overloaded::UninstSubprogramDecl(
+                    self.map_signature(parent, mapping, signature)?,
+                    generic_map.clone(),
+                )
+            }
+            Overloaded::UninstSubprogram(signature, generic_map) => Overloaded::UninstSubprogram(
+                self.map_signature(parent, mapping, signature)?,
+                generic_map.clone(),
+            ),
             Overloaded::InterfaceSubprogram(signature) => {
                 Overloaded::InterfaceSubprogram(self.map_signature(parent, mapping, signature)?)
             }
@@ -379,7 +409,7 @@ impl<'a> AnalyzeContext<'a> {
         })
     }
 
-    fn map_signature(
+    pub(crate) fn map_signature(
         &self,
         parent: Option<EntRef<'a>>,
         mapping: &FnvHashMap<EntityId, TypeEnt<'a>>,

vhdl_lang/src/analysis/semantic.rs

@@ -195,6 +195,11 @@ impl<'a> AnalyzeContext<'a> {
                                 }
                             }
                             diagnostics.push(diagnostic);
+                        } else if ent.is_uninst_subprogram_body() {
+                            diagnostics.error(
+                                &name.pos,
+                                format!("uninstantiated {} cannot be called", ent.describe()),
+                            )
                         }
                     }
                     None => {}

vhdl_lang/src/analysis/standard.rs

@@ -326,7 +326,6 @@ impl<'a> AnalyzeContext<'a> {
 
     fn binary(
         &self,
-
         op: Operator,
         implicit_of: TypeEnt<'a>,
         left: TypeEnt<'a>,

vhdl_lang/src/analysis/tests/mod.rs

@@ -23,6 +23,7 @@ mod resolves_names;
 mod resolves_type_mark;
 mod sensitivity_list;
 mod subprogram_arguments;
+mod subprogram_instance;
 mod tool_directive;
 mod typecheck_expression;
 mod util;