CSY/reowolf Changeset - 3bb9f89521a1 · Centrum Wiskunde & Informatica (CWI)

Changeset - 3bb9f89521a1

Parent rev.

Child rev.

[Not reviewed]

0 9 1

MH - 4 years ago 2021-05-25 18:58:12
contact@maxhenger.nl

Prepare for binding expression inference

10 files changed with 510 insertions and 162 deletions:

src/protocol/ast.rs

src/protocol/ast_printer.rs

src/protocol/parser/depth_visitor.rs

src/protocol/parser/pass_definitions.rs

src/protocol/parser/pass_typing.rs

src/protocol/parser/pass_validation_linking.rs

414

132

src/protocol/tests/eval_casting.rs

src/protocol/tests/mod.rs

src/protocol/tests/parser_binding.rs

src/protocol/tests/utils.rs

0 comments (0 inline, 0 general)

src/protocol/ast.rs

➞

Show inline comments

@@ @@ -613,28 +613,47 @@ impl Scope { @@
             Scope::Synchronous(_) => true,
+        }
+    }
     pub fn to_block(&self) -> BlockStatementId {
         match &self {
             Scope::Regular(id) => *id,
             Scope::Synchronous((_, id)) => *id,
             _ => panic!("unable to get BlockStatement from Scope")
+        }
+    }
+}
 /// `ScopeNode` is a helper that links scopes in two directions. It doesn't
 /// actually contain any information associated with the scope, this may be
 /// found on the AST elements that `Scope` points to.
 #[derive(Debug, Clone)]
 pub struct ScopeNode {
     pub parent: Scope,
     pub nested: Vec<Scope>,
+}
 impl ScopeNode {
     pub(crate) fn new_invalid() -> Self {
         ScopeNode{
             parent: Scope::Definition(DefinitionId::new_invalid()),
             nested: Vec::new(),
+        }
+    }
+}
 #[derive(Debug, Clone)]
 pub enum VariableKind {
     Parameter,
     Local,
     Parameter,      // in parameter list of function/component
     Local,          // declared in function/component body
     Binding,        // may be bound to in a binding expression (determined in validator/linker)
+}
 #[derive(Debug, Clone)]
 pub struct Variable {
     pub this: VariableId,
     // Parsing
     pub kind: VariableKind,
     pub parser_type: ParserType,
     pub identifier: Identifier,
     // Validator/linker
     pub relative_pos_in_block: u32,
     pub unique_id_in_scope: i32, // Temporary fix until proper bytecode/asm is generated
@@ @@ -811,29 +830,29 @@ pub enum EnumVariantValue { @@
+}
 #[derive(Debug, Clone)]
 pub struct EnumVariantDefinition {
     pub identifier: Identifier,
     pub value: EnumVariantValue,
+}
 #[derive(Debug, Clone)]
 pub struct EnumDefinition {
     pub this: EnumDefinitionId,
     pub defined_in: RootId,
-    // Phase 1: symbol scanning
+    // Symbol scanning
     pub span: InputSpan,
     pub identifier: Identifier,
     pub poly_vars: Vec<Identifier>,
-    // Phase 2: parsing
+    // Parsing
     pub variants: Vec<EnumVariantDefinition>,
+}
 impl EnumDefinition {
     pub(crate) fn new_empty(
         this: EnumDefinitionId, defined_in: RootId, span: InputSpan,
         identifier: Identifier, poly_vars: Vec<Identifier>
     ) -> Self {
         Self{ this, defined_in, span, identifier, poly_vars, variants: Vec::new() }
+    }
+}
@@ @@ -1163,25 +1182,25 @@ impl Statement { @@
+    }
+}
 #[derive(Debug, Clone)]
 pub struct BlockStatement {
     pub this: BlockStatementId,
     // Phase 1: parser
     pub is_implicit: bool,
     pub span: InputSpan, // of the complete block
     pub statements: Vec<StatementId>,
     pub end_block: EndBlockStatementId,
     // Phase 2: linker
-    pub parent_scope: Scope,
+    pub scope_node: ScopeNode,
     pub first_unique_id_in_scope: i32, // Temporary fix until proper bytecode/asm is generated
     pub next_unique_id_in_scope: i32, // Temporary fix until proper bytecode/asm is generated
     pub relative_pos_in_parent: u32,
     pub locals: Vec<VariableId>,
     pub labels: Vec<LabeledStatementId>,
+}
 #[derive(Debug, Clone)]
 pub struct EndBlockStatement {
     pub this: EndBlockStatementId,
     // Parser
     pub start_block: BlockStatementId,
@@ @@ -1248,25 +1267,25 @@ pub struct ChannelStatement { @@
     pub relative_pos_in_block: u32,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct LabeledStatement {
     pub this: LabeledStatementId,
     // Phase 1: parser
     pub label: Identifier,
     pub body: StatementId,
     // Phase 2: linker
     pub relative_pos_in_block: u32,
-    pub in_sync: Option<SynchronousStatementId>,
+    pub in_sync: SynchronousStatementId, // may be invalid
+}
 #[derive(Debug, Clone)]
 pub struct IfStatement {
     pub this: IfStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "if" keyword
     pub test: ExpressionId,
     pub true_body: BlockStatementId,
     pub false_body: Option<BlockStatementId>,
     pub end_if: EndIfStatementId,
+}
@@ @@ -1277,25 +1296,25 @@ pub struct EndIfStatement { @@
     pub start_if: IfStatementId,
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct WhileStatement {
     pub this: WhileStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "while" keyword
     pub test: ExpressionId,
     pub body: BlockStatementId,
     pub end_while: EndWhileStatementId,
-    pub in_sync: Option<SynchronousStatementId>,
+    pub in_sync: SynchronousStatementId, // may be invalid
+}
 #[derive(Debug, Clone)]
 pub struct EndWhileStatement {
     pub this: EndWhileStatementId,
     pub start_while: WhileStatementId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct BreakStatement {
@@ @@ -1316,25 +1335,24 @@ pub struct ContinueStatement { @@
     // Phase 2: linker
     pub target: Option<WhileStatementId>,
+}
 #[derive(Debug, Clone)]
 pub struct SynchronousStatement {
     pub this: SynchronousStatementId,
     // Phase 1: parser
     pub span: InputSpan, // of the "sync" keyword
     pub body: BlockStatementId,
     // Phase 2: linker
     pub end_sync: EndSynchronousStatementId,
     pub parent_scope: Option<Scope>,
+}
 #[derive(Debug, Clone)]
 pub struct EndSynchronousStatement {
     pub this: EndSynchronousStatementId,
     pub start_sync: SynchronousStatementId,
     // Phase 2: linker
     pub next: StatementId,
+}
 #[derive(Debug, Clone)]
 pub struct ReturnStatement {
@@ @@ -1577,27 +1595,27 @@ pub struct AssignmentExpression { @@
     pub left: ExpressionId,
     pub operation: AssignmentOperator,
     pub right: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     pub unique_id_in_definition: i32,
+}
 #[derive(Debug, Clone)]
 pub struct BindingExpression {
     pub this: BindingExpressionId,
     // Parsing
     pub span: InputSpan,
     pub left: LiteralExpressionId,
     pub right: ExpressionId,
     pub span: InputSpan, // of the binding keyword
     pub bound_to: ExpressionId,
     pub bound_from: ExpressionId,
     // Validator/Linker
     pub parent: ExpressionParent,
     pub unique_id_in_definition: i32,
+}
 #[derive(Debug, Clone)]
 pub struct ConditionalExpression {
     pub this: ConditionalExpressionId,
     // Parsing
     pub span: InputSpan, // of question mark operator
     pub test: ExpressionId,
     pub true_expression: ExpressionId,

src/protocol/ast_printer.rs

➞

Show inline comments

@@ @@ -463,25 +463,25 @@ impl ASTWriter { @@
             Statement::EndIf(stmt) => {
                 self.kv(indent).with_id(PREFIX_ENDIF_STMT_ID, stmt.this.0.index)
                     .with_s_key("EndIf");
                 self.kv(indent2).with_s_key("StartIf").with_disp_val(&stmt.start_if.0.index);
                 self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.index);
             },
             Statement::While(stmt) => {
                 self.kv(indent).with_id(PREFIX_WHILE_STMT_ID, stmt.this.0.index)
                     .with_s_key("While");
                 self.kv(indent2).with_s_key("EndWhile").with_disp_val(&stmt.end_while.0.index);
                 self.kv(indent2).with_s_key("InSync")
-                    .with_opt_disp_val(stmt.in_sync.as_ref().map(|v| &v.0.index));
+                    .with_disp_val(&stmt.in_sync.0.index);
                 self.kv(indent2).with_s_key("Condition");
                 self.write_expr(heap, stmt.test, indent3);
                 self.kv(indent2).with_s_key("Body");
                 self.write_stmt(heap, stmt.body.upcast(), indent3);
             },
             Statement::EndWhile(stmt) => {
                 self.kv(indent).with_id(PREFIX_ENDWHILE_STMT_ID, stmt.this.0.index)
                     .with_s_key("EndWhile");
                 self.kv(indent2).with_s_key("StartWhile").with_disp_val(&stmt.start_while.0.index);
                 self.kv(indent2).with_s_key("Next").with_disp_val(&stmt.next.index);
             },
             Statement::Break(stmt) => {
@@ @@ -556,28 +556,28 @@ impl ASTWriter { @@
                     .with_s_key("AssignmentExpr");
                 self.kv(indent2).with_s_key("Operation").with_debug_val(&expr.operation);
                 self.kv(indent2).with_s_key("Left");
                 self.write_expr(heap, expr.left, indent3);
                 self.kv(indent2).with_s_key("Right");
                 self.write_expr(heap, expr.right, indent3);
                 self.kv(indent2).with_s_key("Parent")
                     .with_custom_val(|v| write_expression_parent(v, &expr.parent));
             },
             Expression::Binding(expr) => {
                 self.kv(indent).with_id(PREFIX_BINARY_EXPR_ID, expr.this.0.index)
                     .with_s_key("BindingExpr");
                 self.kv(indent2).with_s_key("LeftExpression");
                 self.write_expr(heap, expr.left.upcast(), indent3);
                 self.kv(indent2).with_s_key("RightExpression");
                 self.write_expr(heap, expr.right, indent3);
                 self.kv(indent2).with_s_key("BindToExpression");
                 self.write_expr(heap, expr.bound_to, indent3);
                 self.kv(indent2).with_s_key("BindFromExpression");
                 self.write_expr(heap, expr.bound_from, indent3);
                 self.kv(indent2).with_s_key("Parent")
                     .with_custom_val(|v| write_expression_parent(v, &expr.parent));
             },
             Expression::Conditional(expr) => {
                 self.kv(indent).with_id(PREFIX_CONDITIONAL_EXPR_ID, expr.this.0.index)
                     .with_s_key("ConditionalExpr");
                 self.kv(indent2).with_s_key("Condition");
                 self.write_expr(heap, expr.test, indent3);
                 self.kv(indent2).with_s_key("TrueExpression");
                 self.write_expr(heap, expr.true_expression, indent3);
                 self.kv(indent2).with_s_key("FalseExpression");
                 self.write_expr(heap, expr.false_expression, indent3);

src/protocol/parser/depth_visitor.rs

➞

Show inline comments

@@ @@ -415,26 +415,26 @@ fn recursive_assignment_expression<T: Visitor>( @@
     h: &mut Heap,
     expr: AssignmentExpressionId,
 ) -> VisitorResult {
     this.visit_expression(h, h[expr].left)?;
     this.visit_expression(h, h[expr].right)
+}
 fn recursive_binding_expression<T: Visitor>(
     this: &mut T,
     h: &mut Heap,
     expr: BindingExpressionId,
 ) -> VisitorResult {
     this.visit_expression(h, h[expr].left.upcast())?;
     this.visit_expression(h, h[expr].right)
     this.visit_expression(h, h[expr].bound_from)?;
     this.visit_expression(h, h[expr].bound_to)
+}
 fn recursive_conditional_expression<T: Visitor>(
     this: &mut T,
     h: &mut Heap,
     expr: ConditionalExpressionId,
 ) -> VisitorResult {
     this.visit_expression(h, h[expr].test)?;
     this.visit_expression(h, h[expr].true_expression)?;
     this.visit_expression(h, h[expr].false_expression)
+}

src/protocol/parser/pass_definitions.rs

➞

Show inline comments

@@ @@ -349,25 +349,25 @@ impl PassDefinitions { @@
             self.consume_statement(module, iter, ctx, &mut statements)?;
             let wrap_end_pos = iter.last_valid_pos();
             debug_assert_eq!(statements.len(), 1);
             let statements = statements.into_vec();
             let id = ctx.heap.alloc_block_statement(|this| BlockStatement{
                 this,
                 is_implicit: true,
                 span: InputSpan::from_positions(wrap_begin_pos, wrap_end_pos), // TODO: @Span
                 statements,
                 end_block: EndBlockStatementId::new_invalid(),
-                parent_scope: Scope::Definition(DefinitionId::new_invalid()),
+                scope_node: ScopeNode::new_invalid(),
                 first_unique_id_in_scope: -1,
                 next_unique_id_in_scope: -1,
                 relative_pos_in_parent: 0,
                 locals: Vec::new(),
                 labels: Vec::new()
             });
             let end_block = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
                 this, start_block: id, next: StatementId::new_invalid()
             });
             let block_stmt = &mut ctx.heap[id];
@@ @@ -487,25 +487,25 @@ impl PassDefinitions { @@
+        }
         let statements = stmt_section.into_vec();
         let mut block_span = consume_token(&module.source, iter, TokenKind::CloseCurly)?;
         block_span.begin = open_curly_pos;
         let id = ctx.heap.alloc_block_statement(|this| BlockStatement{
             this,
             is_implicit: false,
             span: block_span,
             statements,
             end_block: EndBlockStatementId::new_invalid(),
-            parent_scope: Scope::Definition(DefinitionId::new_invalid()),
+            scope_node: ScopeNode::new_invalid(),
             first_unique_id_in_scope: -1,
             next_unique_id_in_scope: -1,
             relative_pos_in_parent: 0,
             locals: Vec::new(),
             labels: Vec::new(),
         });
         let end_block = ctx.heap.alloc_end_block_statement(|this| EndBlockStatement{
             this, start_block: id, next: StatementId::new_invalid()
         });
         let block_stmt = &mut ctx.heap[id];
@@ @@ -547,25 +547,25 @@ impl PassDefinitions { @@
         let while_span = consume_exact_ident(&module.source, iter, KW_STMT_WHILE)?;
         consume_token(&module.source, iter, TokenKind::OpenParen)?;
         let test = self.consume_expression(module, iter, ctx)?;
         consume_token(&module.source, iter, TokenKind::CloseParen)?;
         let body = self.consume_block_or_wrapped_statement(module, iter, ctx)?;
         Ok(ctx.heap.alloc_while_statement(|this| WhileStatement{
             this,
             span: while_span,
             test,
             body,
             end_while: EndWhileStatementId::new_invalid(),
-            in_sync: None,
+            in_sync: SynchronousStatementId::new_invalid(),
         }))
+    }
     fn consume_break_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<BreakStatementId, ParseError> {
         let break_span = consume_exact_ident(&module.source, iter, KW_STMT_BREAK)?;
         let label = if Some(TokenKind::Ident) == iter.next() {
             let label = consume_ident_interned(&module.source, iter, ctx)?;
             Some(label)
         } else {
             None
@@ @@ -600,25 +600,24 @@ impl PassDefinitions { @@
     fn consume_synchronous_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<SynchronousStatementId, ParseError> {
         let synchronous_span = consume_exact_ident(&module.source, iter, KW_STMT_SYNC)?;
         let body = self.consume_block_or_wrapped_statement(module, iter, ctx)?;
         Ok(ctx.heap.alloc_synchronous_statement(|this| SynchronousStatement{
             this,
             span: synchronous_span,
             body,
             end_sync: EndSynchronousStatementId::new_invalid(),
             parent_scope: None,
         }))
+    }
     fn consume_return_statement(
         &mut self, module: &Module, iter: &mut TokenIter, ctx: &mut PassCtx
     ) -> Result<ReturnStatementId, ParseError> {
         let return_span = consume_exact_ident(&module.source, iter, KW_STMT_RETURN)?;
         let mut scoped_section = self.expressions.start_section();
         consume_comma_separated_until(
             TokenKind::SemiColon, &module.source, iter, ctx,
             |_source, iter, ctx| self.consume_expression(module, iter, ctx),
@@ @@ -758,25 +757,25 @@ impl PassDefinitions { @@
         // The values in the section need to be in the correct order if some
         // kind of outer block is consumed, so we take another section, push
         // the expressions in that one, and then allocate the labeled statement.
         let mut inner_section = self.statements.start_section();
         self.consume_statement(module, iter, ctx, &mut inner_section)?;
         debug_assert!(inner_section.len() >= 1);
         let stmt_id = ctx.heap.alloc_labeled_statement(|this| LabeledStatement {
             this,
             label,
             body: inner_section[0],
             relative_pos_in_block: 0,
-            in_sync: None,
+            in_sync: SynchronousStatementId::new_invalid(),
         });
         if inner_section.len() == 1 {
             // Produce the labeled statement pointing to the first statement.
             // This is by far the most common case.
             inner_section.forget();
             section.push(stmt_id.upcast());
         } else {
             // Produce the labeled statement using the first statement, and push
             // the remaining ones at the end.
             let inner_statements = inner_section.into_vec();
             section.push(stmt_id.upcast());
@@ @@ -1449,24 +1448,41 @@ impl PassDefinitions { @@
                         KW_LIT_TRUE => Literal::True,
                         KW_LIT_FALSE => Literal::False,
                         _ => unreachable!(),
                     };
                     ctx.heap.alloc_literal_expression(|this| LiteralExpression {
                         this,
                         span: ident_span,
                         value,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -1,
                     }).upcast()
                 } else if ident_text == KW_LET {
                     // Binding expression
                     let keyword_span = iter.next_span();
                     iter.consume();
                     let bound_to = self.consume_expression(module, iter, ctx)?;
                     consume_token(&module.source, iter, TokenKind::Equal)?;
                     let bound_from = self.consume_expression(module, iter, ctx)?;
                     ctx.heap.alloc_binding_expression(|this| BindingExpression{
                         this,
                         span: keyword_span,
                         bound_to,
                         bound_from,
                         parent: ExpressionParent::None,
                         unique_id_in_definition: -1,
                     }).upcast()
                 } else if ident_text == KW_CAST {
                     // Casting expression
                     iter.consume();
                     let to_type = if Some(TokenKind::OpenAngle) == iter.next() {
                         iter.consume();
                         let definition_id = self.cur_definition;
                         let poly_vars = ctx.heap[definition_id].poly_vars();
                         consume_parser_type(
                             &module.source, iter, &ctx.symbols, &ctx.heap,
                             poly_vars, SymbolScope::Module(module.root_id), definition_id,
                             true, 1
                         )?

src/protocol/parser/pass_typing.rs

➞

Show inline comments

@@ @@ -1161,24 +1161,38 @@ impl Visitor2 for PassTyping { @@
         self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let assign_expr = &ctx.heap[id];
         let left_expr_id = assign_expr.left;
         let right_expr_id = assign_expr.right;
         self.visit_expr(ctx, left_expr_id)?;
         self.visit_expr(ctx, right_expr_id)?;
         self.progress_assignment_expr(ctx, id)
+    }
     fn visit_binding_expr(&mut self, ctx: &mut Ctx, id: BindingExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let binding_expr = &ctx.heap[id];
         let bound_to_id = binding_expr.bound_to;
         let bound_from_id = binding_expr.bound_from;
         self.visit_expr(ctx, bound_to_id)?;
         self.visit_expr(ctx, bound_from_id)?;
         self.progress_binding_expr(ctx, id)
+    }
     fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         self.insert_initial_expr_inference_type(ctx, upcast_id)?;
         let conditional_expr = &ctx.heap[id];
         let test_expr_id = conditional_expr.test;
         let true_expr_id = conditional_expr.true_expression;
         let false_expr_id = conditional_expr.false_expression;
         self.visit_expr(ctx, test_expr_id)?;
         self.visit_expr(ctx, true_expr_id)?;
         self.visit_expr(ctx, false_expr_id)?;
@@ @@ -1509,26 +1523,27 @@ impl PassTyping { @@
+        }
         Ok(())
+    }
     fn progress_expr(&mut self, ctx: &mut Ctx, idx: i32) -> Result<(), ParseError> {
         let id = self.expr_types[idx as usize].expr_id; // TODO: @Temp
         match &ctx.heap[id] {
             Expression::Assignment(expr) => {
                 let id = expr.this;
                 self.progress_assignment_expr(ctx, id)
             },
             Expression::Binding(_expr) => {
                 unimplemented!("progress binding expression");
             Expression::Binding(expr) => {
                 let id = expr.this;
                 self.progress_binding_expr(ctx, id)
             },
             Expression::Conditional(expr) => {
                 let id = expr.this;
                 self.progress_conditional_expr(ctx, id)
             },
             Expression::Binary(expr) => {
                 let id = expr.this;
                 self.progress_binary_expr(ctx, id)
             },
             Expression::Unary(expr) => {
                 let id = expr.this;
                 self.progress_unary_expr(ctx, id)
@@ @@ -1602,24 +1617,28 @@ impl PassTyping { @@
         debug_log!("   - Arg1 type [{}]: {}", progress_forced || progress_arg1, self.temp_get_display_name(ctx, arg1_expr_id));
         debug_log!("   - Arg2 type [{}]: {}", progress_arg2, self.temp_get_display_name(ctx, arg2_expr_id));
         debug_log!("   - Expr type [{}]: {}", progress_expr, self.temp_get_display_name(ctx, upcast_id));
         if progress_expr { self.queue_expr_parent(ctx, upcast_id); }
         if progress_forced || progress_arg1 { self.queue_expr(ctx, arg1_expr_id); }
         if progress_arg2 { self.queue_expr(ctx, arg2_expr_id); }
         Ok(())
+    }
     fn progress_binding_expr(&mut self, ctx: &mut Ctx, id: BindingExpressionId) -> Result<(), ParseError> {
+    }
     fn progress_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> Result<(), ParseError> {
         // Note: test expression type is already enforced
         let upcast_id = id.upcast();
         let expr = &ctx.heap[id];
         let arg1_expr_id = expr.true_expression;
         let arg2_expr_id = expr.false_expression;
         debug_log!("Conditional expr: {}", upcast_id.index);
         debug_log!(" * Before:");
         debug_log!("   - Arg1 type: {}", self.temp_get_display_name(ctx, arg1_expr_id));
         debug_log!("   - Arg2 type: {}", self.temp_get_display_name(ctx, arg2_expr_id));
         debug_log!("   - Expr type: {}", self.temp_get_display_name(ctx, upcast_id));

src/protocol/parser/pass_validation_linking.rs

➞

Show inline comments

@@ @@ -34,36 +34,32 @@ impl DefinitionType { @@
+}
 /// This particular visitor will go through the entire AST in a recursive manner
 /// and check if all statements and expressions are legal (e.g. no "return"
 /// statements in component definitions), and will link certain AST nodes to
 /// their appropriate targets (e.g. goto statements, or function calls).
 ///
 /// This visitor will not perform control-flow analysis (e.g. making sure that
 /// each function actually returns) and will also not perform type checking. So
 /// the linking of function calls and component instantiations will be checked
 /// and linked to the appropriate definitions, but the return types and/or
 /// arguments will not be checked for validity.
 ///
 ///
 /// Because of this scheme expressions will not be visited in the breadth-first
 /// pass.
 pub(crate) struct PassValidationLinking {
     // `in_sync` is `Some(id)` if the visitor is visiting the children of a
     // synchronous statement. A single value is sufficient as nested
     // synchronous statements are not allowed
     in_sync: Option<SynchronousStatementId>,
     // `in_while` contains the last encountered `While` statement. This is used
     // to resolve unlabeled `Continue`/`Break` statements.
     in_while: Option<WhileStatementId>,
     // Traversal state, all valid IDs if inside a certain AST element. Otherwise
     // `id.is_invalid()` returns true.
     in_sync: SynchronousStatementId,
     in_while: WhileStatementId, // to resolve labeled continue/break
     in_test_expr: StatementId, // wrapping if/while stmt id
     in_binding_expr: BindingExpressionId, // to resolve variable expressions
     in_binding_expr_lhs: bool,
     // Traversal state: current scope (which can be used to find the parent
     // scope) and the definition variant we are considering.
     cur_scope: Scope,
     def_type: DefinitionType,
     // Parent expression (the previous stmt/expression we visited that could be
     // used as an expression parent)
     expr_parent: ExpressionParent,
     // Set by parent to indicate that child expression must be assignable. The
     // child will throw an error if it is not assignable. The stored span is
     // used for the error's position
     must_be_assignable: Option<InputSpan>,
     // Keeping track of relative positions and unique IDs.
@@ @@ -72,45 +68,52 @@ pub(crate) struct PassValidationLinking { @@
     // Various temporary buffers for traversal. Essentially working around
     // Rust's borrowing rules since it cannot understand we're modifying AST
     // members but not the AST container.
     variable_buffer: ScopedBuffer<VariableId>,
     definition_buffer: ScopedBuffer<DefinitionId>,
     statement_buffer: ScopedBuffer<StatementId>,
     expression_buffer: ScopedBuffer<ExpressionId>,
+}
 impl PassValidationLinking {
     pub(crate) fn new() -> Self {
         Self{
             in_sync: None,
             in_while: None,
             in_sync: SynchronousStatementId::new_invalid(),
             in_while: WhileStatementId::new_invalid(),
             in_test_expr: StatementId::new_invalid(),
             in_binding_expr: BindingExpressionId::new_invalid(),
             in_binding_expr_lhs: false,
             cur_scope: Scope::Definition(DefinitionId::new_invalid()),
             expr_parent: ExpressionParent::None,
             def_type: DefinitionType::Function(FunctionDefinitionId::new_invalid()),
             must_be_assignable: None,
             relative_pos_in_block: 0,
             next_expr_index: 0,
             variable_buffer: ScopedBuffer::new_reserved(128),
             definition_buffer: ScopedBuffer::new_reserved(128),
             statement_buffer: ScopedBuffer::new_reserved(STMT_BUFFER_INIT_CAPACITY),
             expression_buffer: ScopedBuffer::new_reserved(EXPR_BUFFER_INIT_CAPACITY),
+        }
+    }
     fn reset_state(&mut self) {
         self.in_sync = None;
         self.in_while = None;
         self.in_sync = SynchronousStatementId::new_invalid();
         self.in_while = WhileStatementId::new_invalid();
         self.in_test_expr = StatementId::new_invalid();
         self.in_binding_expr = BindingExpressionId::new_invalid();
         self.in_binding_expr_lhs = false;
         self.cur_scope = Scope::Definition(DefinitionId::new_invalid());
         self.expr_parent = ExpressionParent::None;
         self.def_type = DefinitionType::Function(FunctionDefinitionId::new_invalid());
         self.expr_parent = ExpressionParent::None;
         self.must_be_assignable = None;
         self.relative_pos_in_block = 0;
         self.next_expr_index = 0
+    }
+}
 impl Visitor2 for PassValidationLinking {
     fn visit_module(&mut self, ctx: &mut Ctx) -> VisitorResult {
         debug_assert_eq!(ctx.module.phase, ModuleCompilationPhase::TypesAddedToTable);
         let root = &ctx.heap[ctx.module.root_id];
         let section = self.definition_buffer.start_section_initialized(&root.definitions);
         for definition_idx in 0..section.len() {
@@ @@ -141,25 +144,29 @@ impl Visitor2 for PassValidationLinking { @@
         let body_id = definition.body;
         let section = self.variable_buffer.start_section_initialized(&definition.parameters);
         for variable_idx in 0..section.len() {
             let variable_id = section[variable_idx];
             let variable = &mut ctx.heap[variable_id];
             variable.unique_id_in_scope = variable_idx as i32;
+        }
         section.forget();
         // Visit statements in component body
         self.visit_block_stmt(ctx, body_id)?;
         // Assign total number of expressions and assign an in-block unique ID
         // to each of the locals in the procedure.
         ctx.heap[id].num_expressions_in_body = self.next_expr_index;
         self.visit_definition_and_assign_local_ids(ctx, id.upcast());
         Ok(())
+    }
     fn visit_function_definition(&mut self, ctx: &mut Ctx, id: FunctionDefinitionId) -> VisitorResult {
         self.reset_state();
         // Set internal statement indices
         self.def_type = DefinitionType::Function(id);
         self.cur_scope = Scope::Definition(id.upcast());
         self.expr_parent = ExpressionParent::None;
         // Visit parameters and assign a unique scope ID
@@ @@ -167,25 +174,29 @@ impl Visitor2 for PassValidationLinking { @@
         let body_id = definition.body;
         let section = self.variable_buffer.start_section_initialized(&definition.parameters);
         for variable_idx in 0..section.len() {
             let variable_id = section[variable_idx];
             let variable = &mut ctx.heap[variable_id];
             variable.unique_id_in_scope = variable_idx as i32;
+        }
         section.forget();
         // Visit statements in function body
         self.visit_block_stmt(ctx, body_id)?;
         // Assign total number of expressions and assign an in-block unique ID
         // to each of the locals in the procedure.
         ctx.heap[id].num_expressions_in_body = self.next_expr_index;
         self.visit_definition_and_assign_local_ids(ctx, id.upcast());
         Ok(())
+    }
     //--------------------------------------------------------------------------
     // Statement visitors
     //--------------------------------------------------------------------------
     fn visit_block_stmt(&mut self, ctx: &mut Ctx, id: BlockStatementId) -> VisitorResult {
         self.visit_block_stmt_with_hint(ctx, id, None)
+    }
     fn visit_local_memory_stmt(&mut self, _ctx: &mut Ctx, _id: MemoryStatementId) -> VisitorResult {
@@ @@ -195,54 +206,64 @@ impl Visitor2 for PassValidationLinking { @@
     fn visit_local_channel_stmt(&mut self, _ctx: &mut Ctx, _id: ChannelStatementId) -> VisitorResult {
         Ok(())
+    }
     fn visit_labeled_stmt(&mut self, ctx: &mut Ctx, id: LabeledStatementId) -> VisitorResult {
         let body_id = ctx.heap[id].body;
         self.visit_stmt(ctx, body_id)?;
         Ok(())
+    }
     fn visit_if_stmt(&mut self, ctx: &mut Ctx, id: IfStatementId) -> VisitorResult {
         // Traverse expression and bodies
         let (test_id, true_id, false_id) = {
             let stmt = &ctx.heap[id];
             (stmt.test, stmt.true_body, stmt.false_body)
         };
         let if_stmt = &ctx.heap[id];
         let test_expr_id = if_stmt.test;
         let true_stmt_id = if_stmt.true_body;
         let false_stmt_id = if_stmt.false_body;
         // Visit test expression
         debug_assert_eq!(self.expr_parent, ExpressionParent::None);
         debug_assert!(self.in_test_expr.is_invalid());
         self.in_test_expr = id.upcast();
         self.expr_parent = ExpressionParent::If(id);
         self.visit_expr(ctx, test_id)?;
         self.visit_expr(ctx, test_expr_id)?;
         self.in_test_expr = StatementId::new_invalid();
         self.expr_parent = ExpressionParent::None;
         self.visit_block_stmt(ctx, true_id)?;
         if let Some(false_id) = false_id {
         self.visit_block_stmt(ctx, true_stmt_id)?;
         if let Some(false_id) = false_stmt_id {
             self.visit_block_stmt(ctx, false_id)?;
+        }
         Ok(())
+    }
     fn visit_while_stmt(&mut self, ctx: &mut Ctx, id: WhileStatementId) -> VisitorResult {
         let (test_id, body_id) = {
             let stmt = &ctx.heap[id];
             (stmt.test, stmt.body)
         };
         let old_while = self.in_while.replace(id);
         let old_while = self.in_while;
         self.in_while = id;
         // Visit test expression
         debug_assert_eq!(self.expr_parent, ExpressionParent::None);
         debug_assert!(self.in_test_expr.is_invalid());
         self.in_test_expr = id.upcast();
         self.expr_parent = ExpressionParent::While(id);
         self.visit_expr(ctx, test_id)?;
-        self.expr_parent = ExpressionParent::None;
+        self.in_test_expr = StatementId::new_invalid();
         self.expr_parent = ExpressionParent::None;
         self.visit_block_stmt(ctx, body_id)?;
         self.in_while = old_while;
         Ok(())
+    }
     fn visit_break_stmt(&mut self, ctx: &mut Ctx, id: BreakStatementId) -> VisitorResult {
         // Resolve break target
         let target_end_while = {
             let stmt = &ctx.heap[id];
             let target_while_id = self.resolve_break_or_continue_target(ctx, stmt.span, &stmt.label)?;
             let target_while = &ctx.heap[target_while_id];
@@ @@ -264,45 +285,47 @@ impl Visitor2 for PassValidationLinking { @@
             self.resolve_break_or_continue_target(ctx, stmt.span, &stmt.label)?
         };
         let stmt = &mut ctx.heap[id];
         stmt.target = Some(target_while_id);
         Ok(())
+    }
     fn visit_synchronous_stmt(&mut self, ctx: &mut Ctx, id: SynchronousStatementId) -> VisitorResult {
         // Check for validity of synchronous statement
         let cur_sync_span = ctx.heap[id].span;
-        if self.in_sync.is_some() {
+        if !self.in_sync.is_invalid() {
             // Nested synchronous statement
-            let old_sync_span = ctx.heap[self.in_sync.unwrap()].span;
             let old_sync_span = ctx.heap[self.in_sync].span;
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, cur_sync_span, "Illegal nested synchronous statement"
             ).with_info_str_at_span(
                 &ctx.module.source, old_sync_span, "It is nested in this synchronous statement"
             ));
+        }
         if !self.def_type.is_primitive() {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, cur_sync_span,
                 "synchronous statements may only be used in primitive components"
             ));
+        }
         let sync_body = ctx.heap[id].body;
         let old = self.in_sync.replace(id);
         debug_assert!(self.in_sync.is_invalid());
         self.in_sync = id;
         self.visit_block_stmt_with_hint(ctx, sync_body, Some(id))?;
         self.in_sync = old;
         self.in_sync = SynchronousStatementId::new_invalid();
         Ok(())
+    }
     fn visit_return_stmt(&mut self, ctx: &mut Ctx, id: ReturnStatementId) -> VisitorResult {
         // Check if "return" occurs within a function
         let stmt = &ctx.heap[id];
         if !self.def_type.is_function() {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, stmt.span,
                 "return statements may only appear in function bodies"
             ));
@@ @@ -316,29 +339,29 @@ impl Visitor2 for PassValidationLinking { @@
         self.expr_parent = ExpressionParent::None;
         Ok(())
+    }
     fn visit_goto_stmt(&mut self, ctx: &mut Ctx, id: GotoStatementId) -> VisitorResult {
         let target_id = self.find_label(ctx, &ctx.heap[id].label)?;
         ctx.heap[id].target = Some(target_id);
         let target = &ctx.heap[target_id];
         if self.in_sync != target.in_sync {
             // We can only goto the current scope or outer scopes. Because
             // nested sync statements are not allowed so if the value does
             // not match, then we must be inside a sync scope
             debug_assert!(self.in_sync.is_some());
             // nested sync statements are not allowed we must be inside a sync
             // statement.
             debug_assert!(!self.in_sync.is_invalid());
             let goto_stmt = &ctx.heap[id];
-            let sync_stmt = &ctx.heap[self.in_sync.unwrap()];
             let sync_stmt = &ctx.heap[self.in_sync];
             return Err(
                 ParseError::new_error_str_at_span(&ctx.module.source, goto_stmt.span, "goto may not escape the surrounding synchronous block")
                 .with_info_str_at_span(&ctx.module.source, target.label.span, "this is the target of the goto statement")
                 .with_info_str_at_span(&ctx.module.source, sync_stmt.span, "which will jump past this statement")
             );
+        }
         Ok(())
+    }
     fn visit_new_stmt(&mut self, ctx: &mut Ctx, id: NewStatementId) -> VisitorResult {
         // Make sure the new statement occurs inside a composite component
@@ @@ -390,24 +413,95 @@ impl Visitor2 for PassValidationLinking { @@
         self.next_expr_index += 1;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.must_be_assignable = Some(assignment_expr.span);
         self.visit_expr(ctx, left_expr_id)?;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.must_be_assignable = None;
         self.visit_expr(ctx, right_expr_id)?;
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_binding_expr(&mut self, ctx: &mut Ctx, id: BindingExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let binding_expr = &mut ctx.heap[id];
         // Check for valid context of binding expression
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, span, "cannot assign to the result from a binding expression"
             ));
+        }
         if self.in_test_expr.is_invalid() {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, binding_expr.span,
                 "binding expressions can only be used inside the testing expression of 'if' and 'while' statements"
             ));
+        }
         if !self.in_binding_expr.is_invalid() {
             let binding_expr = &ctx.heap[id];
             let previous_expr = &ctx.heap[self.in_binding_expr];
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, binding_expr.span,
                 "nested binding expressions are not allowed"
             ).with_info_str_at_span(
                 &ctx.module.source, previous_expr.span,
                 "the outer binding expression is found here"
             ));
+        }
         let old_expr_parent = self.expr_parent;
         binding_expr.parent = old_expr_parent;
         binding_expr.unique_id_in_definition = self.next_expr_index;
         self.next_expr_index += 1;
         self.in_binding_expr = id;
         // Perform preliminary check on children: binding expressions only make
         // sense if the left hand side is just a variable expression, or if it
         // is a literal of some sort. The typechecker will take care of the rest
         let bound_to_id = binding_expr.bound_to;
         let bound_from_id = binding_expr.bound_from;
         match &ctx.heap[bound_to_id] {
             // Variables may not be binding variables, and literals may
             // actually not contain binding variables. But in that case we just
             // perform an equality check.
             Expression::Variable(_) => {}
             Expression::Literal(_) => {},
             _ => {
                 let binding_expr = &ctx.heap[id];
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module.source, binding_expr.span,
                     "the left hand side of a binding expression may only be a variable or a literal expression"
                 ));
             },
+        }
         // Visit the children themselves
         self.in_binding_expr_lhs = true;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 0);
         self.visit_expr(ctx, bound_to_id);
         self.in_binding_expr_lhs = false;
         self.expr_parent = ExpressionParent::Expression(upcast_id, 1);
         self.visit_expr(ctx, bound_from_id);
         self.expr_parent = old_expr_parent;
         self.in_binding_expr = BindingExpressionId::new_invalid();
         Ok(())
+    }
     fn visit_conditional_expr(&mut self, ctx: &mut Ctx, id: ConditionalExpressionId) -> VisitorResult {
         let upcast_id = id.upcast();
         let conditional_expr = &mut ctx.heap[id];
         if let Some(span) = self.must_be_assignable {
             return Err(ParseError::new_error_str_at_span(
                 &ctx.module.source, span, "cannot assign to the result from a conditional expression"
             ))
+        }
         let test_expr_id = conditional_expr.test;
         let true_expr_id = conditional_expr.true_expression;
@@ @@ -762,69 +856,69 @@ impl Visitor2 for PassValidationLinking { @@
         // Check whether the method is allowed to be called within the code's
         // context (in sync, definition type, etc.)
         let mut expected_wrapping_new_stmt = false;
         match &mut call_expr.method {
             Method::Get => {
                 if !self.def_type.is_primitive() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'get' may only occur in primitive component definitions"
                     ));
+                }
-                if self.in_sync.is_none() {
+                if !self.in_sync.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'get' may only occur inside synchronous blocks"
                     ));
+                }
             },
             Method::Put => {
                 if !self.def_type.is_primitive() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'put' may only occur in primitive component definitions"
                     ));
+                }
-                if self.in_sync.is_none() {
+                if !self.in_sync.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'put' may only occur inside synchronous blocks"
                     ));
+                }
             },
             Method::Fires => {
                 if !self.def_type.is_primitive() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'fires' may only occur in primitive component definitions"
                     ));
+                }
-                if self.in_sync.is_none() {
+                if !self.in_sync.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "a call to 'fires' may only occur inside synchronous blocks"
                     ));
+                }
             },
             Method::Create => {},
             Method::Length => {},
             Method::Assert => {
                 if self.def_type.is_function() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "assert statement may only occur in components"
                     ));
+                }
-                if self.in_sync.is_none() {
+                if !self.in_sync.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, call_expr.span,
                         "assert statements may only occur inside synchronous blocks"
                     ));
+                }
             },
             Method::UserFunction => {},
             Method::UserComponent => {
                 expected_wrapping_new_stmt = true;
             },
+        }
@@ @@ -877,57 +971,161 @@ impl Visitor2 for PassValidationLinking { @@
             self.expr_parent = ExpressionParent::Expression(upcast_id, arg_expr_idx as u32);
             self.visit_expr(ctx, arg_expr_id)?;
+        }
         section.forget();
         self.expr_parent = old_expr_parent;
         Ok(())
+    }
     fn visit_variable_expr(&mut self, ctx: &mut Ctx, id: VariableExpressionId) -> VisitorResult {
         let var_expr = &ctx.heap[id];
         let variable_id = self.find_variable(ctx, self.relative_pos_in_block, &var_expr.identifier)?;
         let variable_id = match self.find_variable(ctx, self.relative_pos_in_block, &var_expr.identifier) {
             Ok(variable_id) => {
                 // Regular variable
                 variable_id
             },
             Err(()) => {
                 // Couldn't find variable, but if we're in a binding expression,
                 // then this may be the thing we're binding to.
                 if self.in_binding_expr.is_invalid() || !self.in_binding_expr_lhs {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, var_expr.identifier.span, "unresolved variable"
                     ));
+                }
                 // This is a binding variable, but it may only appear in very
                 // specific locations.
                 let is_valid_binding = match self.expr_parent {
                     ExpressionParent::Expression(expr_id, idx) => {
                         match &ctx.heap[expr_id] {
                             Expression::Binding(_binding_expr) => {
                                 // Nested binding is disallowed, and because of
                                 // the check above we know we're directly at the
                                 // LHS of the binding expression
                                 debug_assert_eq!(_binding_expr.this, self.in_binding_expr);
                                 debug_assert_eq!(idx, 0);
                                 true
+                            }
                             Expression::Literal(lit_expr) => {
                                 // Only struct, unions and arrays can have
                                 // subexpressions, so we're always fine
                                 if cfg!(debug_assertions) {
                                     match lit_expr.value {
                                         Literal::Struct(_) | Literal::Union(_) | Literal::Array(_) => {},
                                         _ => unreachable!(),
+                                    }
+                                }
                                 true
                             },
                             _ => false,
+                        }
                     },
                     _ => {
                         false
+                    }
                 };
                 if !is_valid_binding {
                     let binding_expr = &ctx.heap[self.in_binding_expr];
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, var_expr.identifier.span,
                         "illegal location for binding variable: binding variables may only be nested under a binding expression, or a struct, union or array literal"
                     ).with_info_at_span(
                         &ctx.module.source, binding_expr.span, format!(
                             "'{}' was interpreted as a binding variable because the variable is not declared and it is nested under this binding expression",
                             var_expr.identifier.value.as_str()
+                        )
                     ));
+                }
                 // By now we know that this is a valid binding expression. Given
                 // that a binding expression must be nested under an if/while
                 // statement, we now add the variable to the (implicit) block
                 // statement following the if/while statement.
                 let bound_identifier = var_expr.identifier.clone();
                 let bound_variable_id = ctx.heap.alloc_variable(|this| Variable{
                     this,
                     kind: VariableKind::Binding,
                     parser_type: ParserType{ elements: vec![
                         ParserTypeElement{ full_span: bound_identifier.span, variant: ParserTypeVariant::Inferred }
                     ]},
                     identifier: bound_identifier,
                     relative_pos_in_block: 0,
                     unique_id_in_scope: -1,
                 });
                 let body_stmt_id = match &ctx.heap[self.in_test_expr] {
                     Statement::If(stmt) => stmt.true_body,
                     Statement::While(stmt) => stmt.body,
                     _ => unreachable!(),
                 };
                 let body_scope = Scope::Regular(body_stmt_id);
                 self.checked_at_single_scope_add_local(ctx, body_scope, 0, bound_variable_id)?;
                 bound_variable_id
+            }
         };
         let var_expr = &mut ctx.heap[id];
         var_expr.declaration = Some(variable_id);
         var_expr.parent = self.expr_parent;
         var_expr.unique_id_in_definition = self.next_expr_index;
         self.next_expr_index += 1;
         Ok(())
+    }
+}
 impl PassValidationLinking {
     //--------------------------------------------------------------------------
     // Special traversal
     //--------------------------------------------------------------------------
     fn visit_block_stmt_with_hint(&mut self, ctx: &mut Ctx, id: BlockStatementId, hint: Option<SynchronousStatementId>) -> VisitorResult {
         // Set parent scope and relative position in the parent scope. Remember
         // these values to set them back to the old values when we're done with
         // the traversal of the block's statements.
         let scope_next_unique_id = get_scope_next_unique_id(ctx, &self.cur_scope);
         let body = &mut ctx.heap[id];
         body.parent_scope = self.cur_scope.clone();
         body.relative_pos_in_parent = self.relative_pos_in_block;
         body.first_unique_id_in_scope = scope_next_unique_id;
         body.next_unique_id_in_scope = scope_next_unique_id;
         let old_scope = self.cur_scope.clone();
-        self.cur_scope = match hint {
+        let new_scope = match hint {
             Some(sync_id) => Scope::Synchronous((sync_id, id)),
             None => Scope::Regular(id),
         };
         match old_scope {
             Scope::Definition(_def_id) => {
                 // Don't do anything. Block is implicitly a child of a
                 // definition scope.
                 if cfg!(debug_assertions) {
                     match &ctx.heap[_def_id] {
                         Definition::Function(proc_def) => debug_assert_eq!(proc_def.body, id),
                         Definition::Component(proc_def) => debug_assert_eq!(proc_def.body, id),
                         _ => unreachable!(),
+                    }
+                }
             },
             Scope::Regular(block_id) | Scope::Synchronous((_, block_id)) => {
                 let parent_block = &mut ctx.heap[block_id];
                 parent_block.scope_node.nested.push(new_scope);
+            }
+        }
         self.cur_scope = new_scope;
         let body = &mut ctx.heap[id];
         body.scope_node.parent = old_scope;
         body.relative_pos_in_parent = self.relative_pos_in_block;
         let old_relative_pos = self.relative_pos_in_block;
         // Copy statement IDs into buffer
         let statement_section = self.statement_buffer.start_section_initialized(&body.statements);
         // Perform the breadth-first pass. Its main purpose is to find labeled
         // statements such that we can find the `goto`-targets immediately when
         // performing the depth pass
         for stmt_idx in 0..statement_section.len() {
             self.relative_pos_in_block = stmt_idx as u32;
             self.visit_statement_for_locals_labels_and_in_sync(ctx, self.relative_pos_in_block, statement_section[stmt_idx])?;
+        }
@@ @@ -943,190 +1141,291 @@ impl PassValidationLinking { @@
         statement_section.forget();
         Ok(())
+    }
     fn visit_statement_for_locals_labels_and_in_sync(&mut self, ctx: &mut Ctx, relative_pos: u32, id: StatementId) -> VisitorResult {
         let statement = &mut ctx.heap[id];
         match statement {
             Statement::Local(stmt) => {
                 match stmt {
                     LocalStatement::Memory(local) => {
                         let variable_id = local.variable;
-                        self.checked_local_add(ctx, relative_pos, variable_id)?;
+                        self.checked_add_local(ctx, relative_pos, variable_id)?;
                     },
                     LocalStatement::Channel(local) => {
                         let from_id = local.from;
                         let to_id = local.to;
                         self.checked_local_add(ctx, relative_pos, from_id)?;
                         self.checked_local_add(ctx, relative_pos, to_id)?;
                         self.checked_add_local(ctx, relative_pos, from_id)?;
                         self.checked_add_local(ctx, relative_pos, to_id)?;
+                    }
+                }
+            }
             Statement::Labeled(stmt) => {
                 let stmt_id = stmt.this;
                 let body_id = stmt.body;
-                self.checked_label_add(ctx, relative_pos, self.in_sync, stmt_id)?;
+                self.checked_add_label(ctx, relative_pos, self.in_sync, stmt_id)?;
                 self.visit_statement_for_locals_labels_and_in_sync(ctx, relative_pos, body_id)?;
             },
             Statement::While(stmt) => {
                 stmt.in_sync = self.in_sync;
             },
             _ => {},
+        }
         return Ok(())
+    }
     fn visit_definition_and_assign_local_ids(&mut self, ctx: &mut Ctx, definition_id: DefinitionId) {
         let mut var_counter = 0;
         // Set IDs on parameters
         let (param_section, body_id) = match &ctx.heap[definition_id] {
             Definition::Function(func_def) => (
                 self.variable_buffer.start_section_initialized(&func_def.parameters),
                 func_def.body
             ),
             Definition::Component(comp_def) => (
                 self.variable_buffer.start_section_initialized(&comp_def.parameters),
                 comp_def.body
             ),
             _ => unreachable!(),
         } ;
         for idx in 0..param_section.len() {
             let var_id = param_section[idx];
             let var = &mut ctx.heap[var_id];
             var.unique_id_in_scope = var_counter;
             var_counter += 1;
+        }
         param_section.forget();
         // Recurse into body
         self.visit_block_and_assign_local_ids(ctx, body_id, var_counter);
+    }
     fn visit_block_and_assign_local_ids(&mut self, ctx: &mut Ctx, block_id: BlockStatementId, mut var_counter: i32) {
         let block_stmt = &mut ctx.heap[block_id];
         block_stmt.first_unique_id_in_scope = var_counter;
         let var_section = self.variable_buffer.start_section_initialized(&block_stmt.locals);
         let mut scope_section = self.statement_buffer.start_section();
         for child_scope in &block_stmt.scope_node.nested {
             debug_assert!(child_scope.is_block(), "found a child scope that is not a block statement");
             scope_section.push(child_scope.to_block().upcast());
+        }
         let mut var_idx = 0;
         let mut scope_idx = 0;
         while var_idx < var_section.len() || scope_idx < scope_section.len() {
             let relative_var_pos = if var_idx < var_section.len() {
                 ctx.heap[var_section[var_idx]].relative_pos_in_block
             } else {
                 u32::MAX
             };
             let relative_scope_pos = if scope_idx < scope_section.len() {
                 ctx.heap[scope_section[scope_idx]].as_block().relative_pos_in_parent
             } else {
                 u32::MAX
             };
             debug_assert!(!(relative_var_pos == u32::MAX && relative_scope_pos == u32::MAX));
             // In certain cases the relative variable position is the same as
             // the scope position (insertion of binding variables). In that case
             // the variable should be treated first
             if relative_var_pos <= relative_scope_pos {
                 let var = &mut ctx.heap[var_section[var_idx]];
                 var.unique_id_in_scope = var_counter;
                 var_counter += 1;
                 var_idx += 1;
             } else {
                 // Boy oh boy
                 let block_id = ctx.heap[scope_section[scope_idx]].as_block().this;
                 self.visit_block_and_assign_local_ids(ctx, block_id, var_counter);
                 scope_idx += 1;
+            }
+        }
         var_section.forget();
         scope_section.forget();
         // Done assigning all IDs, assign the last ID to the block statement scope
         let block_stmt = &mut ctx.heap[block_id];
         block_stmt.next_unique_id_in_scope = var_counter;
+    }
     //--------------------------------------------------------------------------
     // Utilities
     //--------------------------------------------------------------------------
     /// Adds a local variable to the current scope. It will also annotate the
     /// `Local` in the AST with its relative position in the block.
-    fn checked_local_add(&mut self, ctx: &mut Ctx, relative_pos: u32, id: VariableId) -> Result<(), ParseError> {
+    fn checked_add_local(&mut self, ctx: &mut Ctx, relative_pos: u32, id: VariableId) -> Result<(), ParseError> {
         debug_assert!(self.cur_scope.is_block());
         // Make sure we do not conflict with any global symbols
         let cur_scope = SymbolScope::Definition(self.def_type.definition_id());
+        {
             let ident = &ctx.heap[id].identifier;
             if let Some(symbol) = ctx.symbols.get_symbol_by_name(cur_scope, &ident.value.as_bytes()) {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module.source, ident.span,
                     "local variable declaration conflicts with symbol"
                 ).with_info_str_at_span(
                     &ctx.module.source, symbol.variant.span_of_introduction(&ctx.heap), "the conflicting symbol is introduced here"
                 ));
+            }
+        }
         let local = &mut ctx.heap[id];
         local.relative_pos_in_block = relative_pos;
         // Make sure we do not shadow any variables in any of the scopes. Note
         // that variables in parent scopes may be declared later
         let local = &ctx.heap[id];
         let mut scope = &self.cur_scope;
         let mut local_relative_pos = self.relative_pos_in_block;
         loop {
             debug_assert!(scope.is_block(), "scope is not a block");
             // We immediately go to the parent scope. We check the current scope
             // in the call at the end. Likewise for checking the symbol table.
             let block = &ctx.heap[scope.to_block()];
             scope = &block.scope_node.parent;
             if let Scope::Definition(definition_id) = scope {
                 // At outer scope, check parameters of function/component
                 for parameter_id in ctx.heap[*definition_id].parameters() {
                     let parameter = &ctx.heap[*parameter_id];
                     if local.identifier == parameter.identifier {
                         return Err(
                             ParseError::new_error_str_at_span(
                                 &ctx.module.source, local.identifier.span, "Local variable name conflicts with parameter"
                             ).with_info_str_at_span(
                                 &ctx.module.source, parameter.identifier.span, "Parameter definition is found here"
+                            )
                         );
+                    }
+                }
                 // No collisions
                 break;
+            }
             // If here then the parent scope is a block scope
             let local_relative_pos = ctx.heap[scope.to_block()].relative_pos_in_parent;
             for other_local_id in &block.locals {
                 let other_local = &ctx.heap[*other_local_id];
                 // Position check in case another variable with the same name
                 // is defined in a higher-level scope, but later than the scope
                 // in which the current variable resides.
                 if local.this != *other_local_id &&
                     local_relative_pos >= other_local.relative_pos_in_block &&
                     local.identifier == other_local.identifier {
                     // Collision within this scope
                     return Err(
                         ParseError::new_error_str_at_span(
                             &ctx.module.source, local.identifier.span, "Local variable name conflicts with another variable"
                         ).with_info_str_at_span(
                             &ctx.module.source, other_local.identifier.span, "Previous variable is found here"
+                        )
                     );
+                }
+            }
+        }
             // Current scope is fine, move to parent scope if any
             scope = &block.parent_scope;
             if let Scope::Definition(definition_id) = scope {
                 // At outer scope, check parameters of function/component
                 for parameter_id in ctx.heap[*definition_id].parameters() {
                     let parameter = &ctx.heap[*parameter_id];
                     if local.identifier == parameter.identifier {
                         return Err(
                             ParseError::new_error_str_at_span(
                                 &ctx.module.source, local.identifier.span, "Local variable name conflicts with parameter"
                             ).with_info_str_at_span(
                                 &ctx.module.source, parameter.identifier.span, "Parameter definition is found here"
+                            )
                         );
+                    }
+                }
         // No collisions in any of the parent scope, attempt to add to scope
         self.checked_at_single_scope_add_local(ctx, self.cur_scope, relative_pos, id)
+    }
                 break;
     /// Adds a local variable to the specified scope. Will check the specified
     /// scope for variable conflicts and the symbol table for global conflicts.
     /// Will NOT check parent scopes of the specified scope.
     fn checked_at_single_scope_add_local(
         &mut self, ctx: &mut Ctx, scope: Scope, relative_pos: u32, id: VariableId
     ) -> Result<(), ParseError> {
         // Check the symbol table for conflicts
+        {
             let cur_scope = SymbolScope::Definition(self.def_type.definition_id());
             let ident = &ctx.heap[id].identifier;
             if let Some(symbol) = ctx.symbols.get_symbol_by_name(cur_scope, &ident.value.as_bytes()) {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module.source, ident.span,
                     "local variable declaration conflicts with symbol"
                 ).with_info_str_at_span(
                     &ctx.module.source, symbol.variant.span_of_introduction(&ctx.heap), "the conflicting symbol is introduced here"
                 ));
+            }
+        }
             // If here, then we are dealing with a block-like parent block
             local_relative_pos = ctx.heap[scope.to_block()].relative_pos_in_parent;
         // Check the specified scope for conflicts
         let local = &ctx.heap[id];
         debug_assert!(scope.is_block());
         let block = &ctx.heap[scope.to_block()];
         for other_local_id in &block.locals {
             let other_local = &ctx.heap[*other_local_id];
             if local.this != other_local.this &&
                 relative_pos >= other_local.relative_pos_in_block &&
                 local.identifier == other_local.identifier {
                 // Collision
                 return Err(
                     ParseError::new_error_str_at_span(
                         &ctx.module.source, local.identifier.span, "Local variable name conflicts with another variable"
                     ).with_info_str_at_span(
                         &ctx.module.source, other_local.identifier.span, "Previous variable is found here"
+                    )
                 );
+            }
+        }
         // No collisions at all
         let block = &mut ctx.heap[self.cur_scope.to_block()];
         // No collisions
         let block = &mut ctx.heap[scope.to_block()];
         block.locals.push(id);
         let unique_id_in_scope = block.next_unique_id_in_scope;
         block.next_unique_id_in_scope += 1;
         let variable = &mut ctx.heap[id];
         variable.unique_id_in_scope = unique_id_in_scope;
         let local = &mut ctx.heap[id];
         local.relative_pos_in_block = relative_pos;
         Ok(())
+    }
     /// Finds a variable in the visitor's scope that must appear before the
     /// specified relative position within that block.
-    fn find_variable(&self, ctx: &Ctx, mut relative_pos: u32, identifier: &Identifier) -> Result<VariableId, ParseError> {
+    fn find_variable(&self, ctx: &Ctx, mut relative_pos: u32, identifier: &Identifier) -> Result<VariableId, ()> {
         debug_assert!(self.cur_scope.is_block());
         // TODO: May still refer to an alias of a global symbol using a single
         //  identifier in the namespace.
         // No need to use iterator over namespaces if here
         let mut scope = &self.cur_scope;
         loop {
             debug_assert!(scope.is_block());
             let block = &ctx.heap[scope.to_block()];
             for local_id in &block.locals {
                 let local = &ctx.heap[*local_id];
                 if local.relative_pos_in_block < relative_pos && identifier == &local.identifier {
                     return Ok(*local_id);
+                }
+            }
-            scope = &block.parent_scope;
+            scope = &block.scope_node.parent;
             if !scope.is_block() {
                 // Definition scope, need to check arguments to definition
                 match scope {
                     Scope::Definition(definition_id) => {
                         let definition = &ctx.heap[*definition_id];
                         for parameter_id in definition.parameters() {
                             let parameter = &ctx.heap[*parameter_id];
                             if identifier == &parameter.identifier {
                                 return Ok(*parameter_id);
+                            }
+                        }
                     },
                     _ => unreachable!(),
+                }
                 // Variable could not be found
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module.source, identifier.span, "unresolved variable"
                 ));
                 return Err(())
             } else {
                 relative_pos = block.relative_pos_in_parent;
+            }
+        }
+    }
     /// Adds a particular label to the current scope. Will return an error if
     /// there is another label with the same name visible in the current scope.
-    fn checked_label_add(&mut self, ctx: &mut Ctx, relative_pos: u32, in_sync: Option<SynchronousStatementId>, id: LabeledStatementId) -> Result<(), ParseError> {
+    fn checked_add_label(&mut self, ctx: &mut Ctx, relative_pos: u32, in_sync: SynchronousStatementId, id: LabeledStatementId) -> Result<(), ParseError> {
         debug_assert!(self.cur_scope.is_block());
         // Make sure label is not defined within the current scope or any of the
         // parent scope.
         let label = &mut ctx.heap[id];
         label.relative_pos_in_block = relative_pos;
         label.in_sync = in_sync;
         let label = &ctx.heap[id];
         let mut scope = &self.cur_scope;
         loop {
@@ @@ -1135,25 +1434,25 @@ impl PassValidationLinking { @@
             for other_label_id in &block.labels {
                 let other_label = &ctx.heap[*other_label_id];
                 if other_label.label == label.label {
                     // Collision
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, label.label.span, "label name is used more than once"
                     ).with_info_str_at_span(
                         &ctx.module.source, other_label.label.span, "the other label is found here"
                     ));
+                }
+            }
-            scope = &block.parent_scope;
+            scope = &block.scope_node.parent;
             if !scope.is_block() {
                 break;
+            }
+        }
         // No collisions
         let block = &mut ctx.heap[self.cur_scope.to_block()];
         block.labels.push(id);
         Ok(())
+    }
@@ @@ -1181,48 +1480,48 @@ impl PassValidationLinking { @@
                         if local.relative_pos_in_block > relative_scope_pos && local.relative_pos_in_block < label.relative_pos_in_block {
                             return Err(
                                 ParseError::new_error_str_at_span(&ctx.module.source, identifier.span, "this target label skips over a variable declaration")
                                 .with_info_str_at_span(&ctx.module.source, label.label.span, "because it jumps to this label")
                                 .with_info_str_at_span(&ctx.module.source, local.identifier.span, "which skips over this variable")
                             );
+                        }
+                    }
                     return Ok(*label_id);
+                }
+            }
-            scope = &block.parent_scope;
+            scope = &block.scope_node.parent;
             if !scope.is_block() {
                 return Err(ParseError::new_error_str_at_span(
                     &ctx.module.source, identifier.span, "could not find this label"
                 ));
+            }
+        }
+    }
     /// This function will check if the provided while statement ID has a block
     /// statement that is one of our current parents.
     fn has_parent_while_scope(&self, ctx: &Ctx, id: WhileStatementId) -> bool {
         let mut scope = &self.cur_scope;
         let while_stmt = &ctx.heap[id];
         loop {
             debug_assert!(scope.is_block());
             let block = scope.to_block();
             if while_stmt.body == block {
                 return true;
+            }
             let block = &ctx.heap[block];
-            scope = &block.parent_scope;
+            scope = &block.scope_node.parent;
             if !scope.is_block() {
                 return false;
+            }
+        }
+    }
     /// This function should be called while dealing with break/continue
     /// statements. It will try to find the targeted while statement, using the
     /// target label if provided. If a valid target is found then the loop's
     /// ID will be returned, otherwise a parsing error is constructed.
     /// The provided input position should be the position of the break/continue
     /// statement.
@@ @@ -1247,59 +1546,42 @@ impl PassValidationLinking { @@
                     target_stmt.this
                 } else {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, label.span, "incorrect break target label, it must target a while loop"
                     ).with_info_str_at_span(
                         &ctx.module.source, target.label.span, "The targeted label is found here"
                     ));
+                }
             },
             None => {
                 // Use the enclosing while statement, the break must be
                 // nested within that while statement
-                if self.in_while.is_none() {
+                if self.in_while.is_invalid() {
                     return Err(ParseError::new_error_str_at_span(
                         &ctx.module.source, span, "Break statement is not nested under a while loop"
                     ));
+                }
-                self.in_while.unwrap()
                 self.in_while
+            }
         };
         // We have a valid target for the break statement. But we need to
         // make sure we will not break out of a synchronous block
+        {
             let target_while = &ctx.heap[target];
             if target_while.in_sync != self.in_sync {
                 // Break is nested under while statement, so can only escape a
                 // sync block if the sync is nested inside the while statement.
                 debug_assert!(self.in_sync.is_some());
                 let sync_stmt = &ctx.heap[self.in_sync.unwrap()];
                 debug_assert!(!self.in_sync.is_invalid());
                 let sync_stmt = &ctx.heap[self.in_sync];
                 return Err(
                     ParseError::new_error_str_at_span(&ctx.module.source, span, "break may not escape the surrounding synchronous block")
                         .with_info_str_at_span(&ctx.module.source, target_while.span, "the break escapes out of this loop")
                         .with_info_str_at_span(&ctx.module.source, sync_stmt.span, "And would therefore escape this synchronous block")
                 );
+            }
+        }
         Ok(target)
+    }
+}
 fn get_scope_next_unique_id(ctx: &Ctx, scope: &Scope) -> i32 {
     match scope {
         Scope::Definition(definition_id) => {
             let definition = &ctx.heap[*definition_id];
             match definition {
                 Definition::Component(definition) => definition.parameters.len() as i32,
                 Definition::Function(definition) => definition.parameters.len() as i32,
                 _ => unreachable!("Scope::Definition points to non-procedure type")
+            }
         },
         Scope::Synchronous((_, block_id)) | Scope::Regular(block_id) => {
             let block = &ctx.heap[*block_id];
             block.next_unique_id_in_scope
+        }
+    }
+}
@@ \ No newline at end of file @@

src/protocol/tests/eval_casting.rs

➞

Show inline comments

@@ @@ -54,28 +54,34 @@ fn test_invalid_casting() { @@
     fn perform_test(input_type: &str, input_value: &str, output_type: &str) {
         Tester::new_single_source_expect_ok(
             format!("invalid cast {} to {}", input_type, output_type),
             generate_source(input_type, input_value, output_type)
         ).for_function("foo", |f| {
             f.call_err(&format!("'{}' which doesn't fit in a type '{}'", input_value, output_type));
         });
+    }
     // Not exhaustive, good enough
     let tests = [
         // Unsigned large to small width
         ("u16", "256", "u8"),
         ("u32", "256", "u8"),
         ("u64", "256", "u8"),
         ("u32", "65536", "u16"),
         ("u64", "65536", "u16"),
         // Signed to unsigned
         ("s8", "-1", "u8"),
         ("s32", "-1", "u16"),
         ("s32", "65536", "u16"),
         // Signed to signed of smaller width
         ("s16", "-129", "s8"),
         ("s16", "128", "s8")
         ("s16", "128", "s8"),
         // Unsigned to signed
         ("u8", "128", "s8"),
         ("u16", "32768", "s16")
     ];
     for (input_type, input_value, output_type) in &tests {
         perform_test(input_type, input_value, output_type);
+    }
+}
@@ \ No newline at end of file @@

src/protocol/tests/mod.rs

➞

Show inline comments

@@ @@ -5,19 +5,20 @@ @@
  * code. These are intended to be temporary tests such that we're sure that we
  * don't break existing functionality.
+ *
  * In the future these should be replaced by proper testing protocols.
  */
 mod utils;
 mod lexer;
 mod parser_validation;
 mod parser_inference;
 mod parser_monomorphs;
 mod parser_imports;
 mod parser_binding;
 mod eval_operators;
 mod eval_calls;
 mod eval_casting;
 mod eval_silly;
 pub(crate) use utils::{Tester}; // the testing harness
 pub(crate) use crate::protocol::eval::value::*; // to test functions
@@ \ No newline at end of file @@

src/protocol/tests/parser_binding.rs

➞

Show inline comments

@@ new file 100644 @@
 use super::*;
 #[test]
 fn test_correct_binding() {
     Tester::new_single_source_expect_ok("binding bare", )
+}
@@ \ No newline at end of file @@

src/protocol/tests/utils.rs

➞

Show inline comments

@@ @@ -583,25 +583,25 @@ impl<'a> FunctionTester<'a> { @@
         use crate::runtime::*;
         let (prompt, result) = self.eval_until_end();
         match result {
             Ok(_) => {
                 assert!(
                     prompt.store.stack.len() > 0, // note: stack never shrinks
                     "[{}] No value on stack after calling function for {}",
                     self.ctx.test_name, self.assert_postfix()
                 );
             },
             Err(err) => {
                 println!("DEBUG: Formatted error:\n{}", err);
+                println!("DEBUG: Formatted evaluation error:\n{}", err);
                 assert!(
                     false,
                     "[{}] Expected call to succeed, but got {:?} for {}",
                     self.ctx.test_name, err, self.assert_postfix()
+                )
+            }
+        }
         if let Some(expected_result) = expected_result {
             debug_assert!(expected_result.get_heap_pos().is_none(), "comparing against heap thingamajigs is not yet implemented");
             assert!(
                 value::apply_equality_operator(&prompt.store, &prompt.store.stack[0], &expected_result),
@@ @@ -619,25 +619,25 @@ impl<'a> FunctionTester<'a> { @@
         use crate::runtime::*;
         let (_, result) = self.eval_until_end();
         match result {
             Ok(_) => {
                 assert!(
                     false,
                     "[{}] Expected an error, but evaluation finished successfully for {}",
                     self.ctx.test_name, self.assert_postfix()
                 );
             },
             Err(err) => {
-                println!("DEBUG: Got evaluation error:\n{}", err);
+                println!("DEBUG: Formatted evaluation error:\n{}", err);
                 debug_assert_eq!(err.statements.len(), 1);
                 assert!(
                     err.statements[0].message.contains(&expected_result),
                     "[{}] Expected error message to contain '{}', but it was '{}' for {}",
                     self.ctx.test_name, expected_result, err.statements[0].message, self.assert_postfix()
                 );
+            }
+        }
         self
+    }
 fn seek_expr_in_expr<F: Fn(&Expression) -> bool>(heap: &Heap, start: ExpressionId, f: &F) -> Option<ExpressionId> {
     let expr = &heap[start];
     if f(expr) { return Some(start); }
     match expr {
         Expression::Assignment(expr) => {
             None
             .or_else(|| seek_expr_in_expr(heap, expr.left, f))
             .or_else(|| seek_expr_in_expr(heap, expr.right, f))
         },
         Expression::Binding(expr) => {
             None
             .or_else(|| seek_expr_in_expr(heap, expr.left.upcast(), f))
             .or_else(|| seek_expr_in_expr(heap, expr.right, f))
             .or_else(|| seek_expr_in_expr(heap, expr.bound_to, f))
             .or_else(|| seek_expr_in_expr(heap, expr.bound_from, f))
+        }
         Expression::Conditional(expr) => {
             None
             .or_else(|| seek_expr_in_expr(heap, expr.test, f))
             .or_else(|| seek_expr_in_expr(heap, expr.true_expression, f))
             .or_else(|| seek_expr_in_expr(heap, expr.false_expression, f))
         },
         Expression::Binary(expr) => {
             None
             .or_else(|| seek_expr_in_expr(heap, expr.left, f))
             .or_else(|| seek_expr_in_expr(heap, expr.right, f))
         },

0 comments (0 inline, 0 general)