dart2js: num.compareTo is pure, and a.compareTo(a) is zero

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

 // Copyright (c) 2012, 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 '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/names.dart' show Selectors;
 import '../common/tasks.dart' show CompilerTask;
 import '../compiler.dart' show Compiler;
 import '../constants/constant_system.dart';
 import '../constants/values.dart';
@@ skipping 384 matching lines @@
     // Try constant folding the instruction.
     Operation operation = node.specializer.operation(constantSystem);
     if (operation != null) {
       HInstruction instruction = node.inputs.length == 2
           ? foldUnary(operation, node.inputs[1])
           : foldBinary(operation, node.inputs[1], node.inputs[2]);
       if (instruction != null) return instruction;
     }
 
     // Try converting the instruction to a builtin instruction.
-    HInstruction instruction = node.specializer.tryConvertToBuiltin(
-        node, _globalInferenceResults, _options, _helpers, _closedWorld);
+    HInstruction instruction = node.specializer.tryConvertToBuiltin(node,
+        _graph, _globalInferenceResults, _options, _helpers, _closedWorld);
     if (instruction != null) return instruction;
 
     Selector selector = node.selector;
     TypeMask mask = node.mask;
     HInstruction input = node.inputs[1];
 
     bool applies(MemberEntity element) {
       return selector.applies(element) &&
           (mask == null || mask.canHit(element, selector, _closedWorld));
     }
@@ skipping 742 matching lines @@
       // All intercepted classes extend `Interceptor`, so if the receiver can't
       // be a class extending `Interceptor` then it can be called directly.
       if (new TypeMask.nonNullSubclass(
               _helpers.jsInterceptorClass, _closedWorld)
           .isDisjoint(input.instructionType, _closedWorld)) {
         var inputs = <HInstruction>[input, input]; // [interceptor, receiver].
         HInstruction result = new HInvokeDynamicMethod(
             selector,
             input.instructionType, // receiver mask.
             inputs,
-            toStringType)..sourceInformation = node.sourceInformation;
+            toStringType)
+          ..sourceInformation = node.sourceInformation;
         return result;
       }
       return null;
     }
 
     return tryConstant() ?? tryToString() ?? node;
   }
 
   HInstruction visitOneShotInterceptor(HOneShotInterceptor node) {
     return handleInterceptedCall(node);
@@ skipping 1656 matching lines @@
 
     keyedValues.forEach((receiver, values) {
       result.keyedValues[receiver] =
           new Map<HInstruction, HInstruction>.from(values);
     });
 
     result.nonEscapingReceivers.addAll(nonEscapingReceivers);
     return result;
   }
 }