Compute ResolutionImpact directly from kernel, part 1 of ?

pkg/compiler/lib/src/ssa/kernel_impact.dart

+// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:kernel/ast.dart' as ir;
+
+import '../common.dart';
+import '../compiler.dart';
+import '../constants/expressions.dart';
+import '../dart_types.dart';
+import '../elements/elements.dart';
+import '../js_backend/backend.dart' show JavaScriptBackend;
+import '../kernel/kernel.dart';
+import '../kernel/kernel_visitor.dart';
+import '../resolution/registry.dart' show ResolutionWorldImpactBuilder;
+import '../universe/feature.dart';
+import '../universe/use.dart';
+
+import 'kernel_ast_adapter.dart';
+import '../common/resolution.dart';
+
+/// Computes the [ResolutionImpact] for [resolvedAst] through kernel.
+ResolutionImpact build(Compiler compiler, ResolvedAst resolvedAst) {
+  AstElement element = resolvedAst.element.implementation;
+  Kernel kernel = new Kernel(compiler);
+  KernelVisitor visitor =
+      new KernelVisitor(element, resolvedAst.elements, kernel);
+  IrFunction function;
+  try {
+    function = visitor.buildFunction();
+  } catch (e) {
+    throw "Failed to convert to Kernel IR: $e";
+  }
+  KernelImpactBuilder builder = new KernelImpactBuilder(
+      function, element, resolvedAst, compiler, visitor, kernel);
+  return builder.build();
+}
+
+class KernelImpactBuilder extends ir.Visitor {
+  final IrFunction function;
+  final FunctionElement functionElement;
+  final ResolvedAst resolvedAst;
+  final Compiler compiler;
+
+  JavaScriptBackend get backend => compiler.backend;
+
+  ResolutionWorldImpactBuilder worldImpact;
+  KernelAstAdapter astAdapter;
+
+  KernelImpactBuilder(this.function, this.functionElement, this.resolvedAst,
+      this.compiler, KernelVisitor visitor, Kernel kernel) {
+    this.worldImpact = new ResolutionWorldImpactBuilder('$functionElement');
+    this.astAdapter = new KernelAstAdapter(
+        compiler.backend,
+        resolvedAst,
+        visitor.nodeToAst,
+        visitor.nodeToElement,
+        kernel.functions,
+        kernel.classes,
+        kernel.libraries);
+  }
+
+  ResolutionImpact build() {
+    if (function.kind == ir.ProcedureKind.Method ||
+        function.kind == ir.ProcedureKind.Operator) {
+      buildMethod(function);
+    } else {
+      compiler.reporter.internalError(
+          functionElement,
+          "Unable to compute resolution impact for this kind of Kernel "
+          "procedure: ${function.kind}");
+    }
+    return worldImpact;
+  }
+
+  /// Add a checked-mode type use of [type] if it is not `dynamic`.
+  DartType checkType(DartType type) {
+    if (!type.isDynamic) {
+      worldImpact.registerTypeUse(new TypeUse.checkedModeCheck(type));
+    }
+    return type;
+  }
+
+  void buildMethod(IrFunction method) {
+    method.node.body.accept(this);
+  }
+
+  void visitNodes(Iterable<ir.Node> nodes) {
+    nodes.forEach((ir.Node node) => node.accept(this));
+  }
+
+  @override
+  void visitBlock(ir.Block block) => visitNodes(block.statements);
+
+  @override
+  void visitExpressionStatement(ir.ExpressionStatement exprStatement) {
+    exprStatement.expression.accept(this);
+  }
+
+  @override
+  void visitReturnStatement(ir.ReturnStatement returnStatement) {
+    returnStatement.expression?.accept(this);
+  }
+
+  @override
+  void visitIfStatement(ir.IfStatement ifStatement) {
+    ifStatement.condition.accept(this);
+    ifStatement.then.accept(this);
+    ifStatement.otherwise?.accept(this);
+  }
+
+  @override
+  void visitIntLiteral(ir.IntLiteral literal) {
+    worldImpact
+        .registerConstantLiteral(new IntConstantExpression(literal.value));
+  }
+
+  @override
+  void visitDoubleLiteral(ir.DoubleLiteral literal) {
+    worldImpact
+        .registerConstantLiteral(new DoubleConstantExpression(literal.value));
+  }
+
+  @override
+  void visitBoolLiteral(ir.BoolLiteral literal) {
+    worldImpact
+        .registerConstantLiteral(new BoolConstantExpression(literal.value));
+  }
+
+  @override
+  void visitStringLiteral(ir.StringLiteral literal) {
+    worldImpact
+        .registerConstantLiteral(new StringConstantExpression(literal.value));
+  }
+
+  @override
+  void visitSymbolLiteral(ir.SymbolLiteral literal) {
+    worldImpact.registerConstSymbolName(literal.value);
+  }
+
+  @override
+  void visitNullLiteral(ir.NullLiteral literal) {
+    worldImpact.registerConstantLiteral(new NullConstantExpression());
+  }
+
+  @override
+  void visitListLiteral(ir.ListLiteral literal) {
+    visitNodes(literal.expressions);
+    DartType elementType =
+        checkType(astAdapter.getDartType(literal.typeArgument));
+
+    worldImpact.registerListLiteral(new ListLiteralUse(
+        compiler.coreTypes.listType(elementType),
+        isConstant: literal.isConst,
+        isEmpty: literal.expressions.isEmpty));
+  }
+
+  @override
+  void visitMapLiteral(ir.MapLiteral literal) {
+    visitNodes(literal.entries);
+    DartType keyType = checkType(astAdapter.getDartType(literal.keyType));
+    DartType valueType = checkType(astAdapter.getDartType(literal.valueType));
+    worldImpact.registerMapLiteral(new MapLiteralUse(
+        compiler.coreTypes.mapType(keyType, valueType),
+        isConstant: literal.isConst,
+        isEmpty: literal.entries.isEmpty));
+  }
+
+  void visitMapEntry(ir.MapEntry entry) {
+    entry.key.accept(this);
+    entry.value.accept(this);
+  }
+
+  void _visitArguments(ir.Arguments arguments) {
+    for (ir.Expression argument in arguments.positional) {
+      argument.accept(this);
+    }
+    for (ir.NamedExpression argument in arguments.named) {
+      argument.value.accept(this);
+    }
+  }
+
+  @override
+  void visitStaticInvocation(ir.StaticInvocation invocation) {
+    _visitArguments(invocation.arguments);
+    Element target = astAdapter.getElement(invocation.target).declaration;
+    worldImpact.registerStaticUse(new StaticUse.staticInvoke(
+        target, astAdapter.getCallStructure(invocation.arguments)));
+  }
+
+  @override
+  void visitMethodInvocation(ir.MethodInvocation invocation) {
+    invocation.receiver.accept(this);
+    _visitArguments(invocation.arguments);
+    worldImpact.registerDynamicUse(
+        new DynamicUse(astAdapter.getSelector(invocation), null));
+  }
+
+  @override
+  void visitNot(ir.Not not) {
+    not.operand.accept(this);
+  }
+}