Added IntermediateValue constant results, EvaluationReferences to store values.
Pre-work for variable declarations and method invocation. Storing values in locations (refs) and having the ability to update the values.
Change-Id: I682c139dfebbc4ef6f5032d4f53f29f08b8ceeb8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/188500
Commit-Queue: Kallen Tu <kallentu@google.com>
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
diff --git a/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart b/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
index 0d2f50f..547cc29 100644
--- a/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/constant_evaluator.dart
@@ -544,7 +544,7 @@
if (node.initializer != null) {
if (node.isConst) {
final Constant constant = evaluateWithContext(node, node.initializer);
- constantEvaluator.env.addVariableValue(node, constant);
+ constantEvaluator.env.updateVariableValue(node, constant);
node.initializer = makeConstantExpression(constant, node.initializer)
..parent = node;
@@ -1644,14 +1644,14 @@
// TODO(johnniwinther): This should call [_evaluateSubexpression].
: _evaluateNullableSubexpression(parameter.initializer);
if (value is AbortConstant) return value;
- env.addVariableValue(parameter, value);
+ env.updateVariableValue(parameter, value);
}
for (final VariableDeclaration parameter in function.namedParameters) {
final Constant value = namedArguments[parameter.name] ??
// TODO(johnniwinther): This should call [_evaluateSubexpression].
_evaluateNullableSubexpression(parameter.initializer);
if (value is AbortConstant) return value;
- env.addVariableValue(parameter, value);
+ env.updateVariableValue(parameter, value);
}
// Step 2) Run all initializers (including super calls) with environment
@@ -1672,7 +1672,7 @@
final VariableDeclaration variable = init.variable;
Constant constant = _evaluateSubexpression(variable.initializer);
if (constant is AbortConstant) return constant;
- env.addVariableValue(variable, constant);
+ env.updateVariableValue(variable, constant);
} else if (init is SuperInitializer) {
AbortConstant error = checkConstructorConst(init, constructor);
if (error != null) return error;
@@ -2374,7 +2374,7 @@
Constant visitLet(Let node) {
Constant value = _evaluateSubexpression(node.variable.initializer);
if (value is AbortConstant) return value;
- env.addVariableValue(node.variable, value);
+ env.updateVariableValue(node.variable, value);
return _evaluateSubexpression(node.body);
}
@@ -2729,14 +2729,14 @@
// TODO(johnniwinther): This should call [_evaluateSubexpression].
: _evaluateNullableSubexpression(parameter.initializer);
if (value is AbortConstant) return value;
- env.addVariableValue(parameter, value);
+ env.updateVariableValue(parameter, value);
}
for (final VariableDeclaration parameter in function.namedParameters) {
final Constant value = namedArguments[parameter.name] ??
// TODO(johnniwinther): This should call [_evaluateSubexpression].
_evaluateNullableSubexpression(parameter.initializer);
if (value is AbortConstant) return value;
- env.addVariableValue(parameter, value);
+ env.updateVariableValue(parameter, value);
}
Statement body = function.body;
if (body is ReturnStatement) {
@@ -3269,9 +3269,9 @@
final Map<TypeParameter, DartType> _typeVariables =
<TypeParameter, DartType>{};
- /// The values of the parameters/variables in scope.
- final Map<VariableDeclaration, Constant> _variables =
- <VariableDeclaration, Constant>{};
+ /// The references to values of the parameters/variables in scope.
+ final Map<VariableDeclaration, EvaluationReference> _variables =
+ <VariableDeclaration, EvaluationReference>{};
/// The variables that hold unevaluated constants.
///
@@ -3288,15 +3288,19 @@
_typeVariables[parameter] = value;
}
- void addVariableValue(VariableDeclaration variable, Constant value) {
- _variables[variable] = value;
+ void updateVariableValue(VariableDeclaration variable, Constant value) {
+ if (!_variables.containsKey(variable)) {
+ _variables[variable] = new EvaluationReference(value);
+ } else {
+ _variables[variable].value = value;
+ }
if (value is UnevaluatedConstant) {
_unreadUnevaluatedVariables.add(variable);
}
}
Constant lookupVariable(VariableDeclaration variable) {
- Constant value = _variables[variable];
+ Constant value = _variables[variable]?.value;
if (value is UnevaluatedConstant) {
_unreadUnevaluatedVariables.remove(variable);
}
@@ -3307,7 +3311,7 @@
Iterable<UnevaluatedConstant> get unevaluatedUnreadConstants {
if (_unreadUnevaluatedVariables.isEmpty) return const [];
return _unreadUnevaluatedVariables.map<UnevaluatedConstant>(
- (VariableDeclaration variable) => _variables[variable]);
+ (VariableDeclaration variable) => _variables[variable].value);
}
DartType substituteType(DartType type) {
@@ -3333,6 +3337,70 @@
}
}
+/// Location that stores a value in the [ConstantEvaluator].
+class EvaluationReference {
+ Constant value;
+
+ EvaluationReference(this.value);
+}
+
+/// An intermediate result that is used within the [ConstantEvaluator].
+class IntermediateValue implements Constant {
+ dynamic value;
+
+ IntermediateValue(this.value);
+
+ @override
+ R accept<R>(ConstantVisitor<R> v) {
+ throw new UnimplementedError();
+ }
+
+ @override
+ R acceptReference<R>(Visitor<R> v) {
+ throw new UnimplementedError();
+ }
+
+ @override
+ Expression asExpression() {
+ throw new UnimplementedError();
+ }
+
+ @override
+ DartType getType(StaticTypeContext context) {
+ throw new UnimplementedError();
+ }
+
+ @override
+ String leakingDebugToString() {
+ throw new UnimplementedError();
+ }
+
+ @override
+ String toString() {
+ throw new UnimplementedError();
+ }
+
+ @override
+ String toStringInternal() {
+ throw new UnimplementedError();
+ }
+
+ @override
+ String toText(AstTextStrategy strategy) {
+ throw new UnimplementedError();
+ }
+
+ @override
+ void toTextInternal(AstPrinter printer) {
+ throw new UnimplementedError();
+ }
+
+ @override
+ void visitChildren(Visitor<dynamic> v) {
+ throw new UnimplementedError();
+ }
+}
+
abstract class AbortConstant implements Constant {}
class _AbortDueToErrorConstant extends AbortConstant {
