implement kernel -> ssa for simple binary expression

pkg/compiler/lib/src/ssa/kernel_ast_adapter.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 '../compiler.dart';
 import '../constants/values.dart';
 import '../diagnostics/invariant.dart';
 import '../elements/elements.dart';
 import '../js_backend/js_backend.dart';
+import '../resolution/tree_elements.dart';
 import '../tree/tree.dart' as ast;
 import '../types/masks.dart';
+import '../universe/selector.dart';
 import '../universe/side_effects.dart';
 
 import 'types.dart';
 
 /// A helper class that abstracts all accesses of the AST from Kernel nodes.
 ///
 /// The goal is to remove all need for the AST from the Kernel SSA builder.
 class KernelAstAdapter {
   final JavaScriptBackend _backend;
   final ResolvedAst _resolvedAst;
   final Map<ir.Node, ast.Node> _nodeToAst;
   final Map<ir.Node, Element> _nodeToElement;
 
   KernelAstAdapter(this._backend, this._resolvedAst, this._nodeToAst,
       this._nodeToElement, Map<FunctionElement, ir.Member> functions) {
     for (FunctionElement functionElement in functions.keys) {
       _nodeToElement[functions[functionElement]] = functionElement;
     }
   }
 
+  Compiler get _compiler => _backend.compiler;
+  TreeElements get _elements => _resolvedAst.elements;
+
   ConstantValue getConstantForSymbol(ir.SymbolLiteral node) {
-    ast.Node astNode = _nodeToAst[node];
+    ast.Node astNode = getNode(node);
     ConstantValue constantValue = _backend.constants
         .getConstantValueForNode(astNode, _resolvedAst.elements);
     assert(invariant(astNode, constantValue != null,
         message: 'No constant computed for $node'));
     return constantValue;
   }
 
   Element getElement(ir.Node node) {
     Element result = _nodeToElement[node];
     assert(result != null);
     return result;
   }
 
+  ast.Node getNode(ir.Node node) {
+    ast.Node result = _nodeToAst[node];
+    assert(result != null);
+    return result;
+  }
+
   bool getCanThrow(ir.Procedure procedure) {
     FunctionElement function = getElement(procedure);
-    return !_backend.compiler.world.getCannotThrow(function);
+    return !_compiler.world.getCannotThrow(function);
   }
 
   TypeMask returnTypeOf(ir.Procedure node) {
     return TypeMaskFactory.inferredReturnTypeForElement(
-        getElement(node), _backend.compiler);
+        getElement(node), _compiler);
   }
 
   SideEffects getSideEffects(ir.Node node) {
-    return _backend.compiler.world.getSideEffectsOfElement(getElement(node));
+    return _compiler.world.getSideEffectsOfElement(getElement(node));
+  }
+
+  // TODO(het): Create the selector directly from the invocation
+  Selector getSelector(ir.MethodInvocation invocation) {
+    return _elements.getSelector(getNode(invocation));
+  }
+
+  TypeMask getTypeMask(ir.MethodInvocation invocation) {
+    return _elements.getTypeMask(getNode(invocation));
+  }
+
+  TypeMask selectorTypeOf(ir.MethodInvocation invocation) {
+    return TypeMaskFactory.inferredTypeForSelector(
+        getSelector(invocation), getTypeMask(invocation), _compiler);
+  }
+
+  bool isIntercepted(ir.MethodInvocation invocation) {
+    return _backend.isInterceptedSelector(getSelector(invocation));
   }
 }