Support !=.

dart/frog/leg/ssa/builder.dart

 // Copyright (c) 2011, 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.
 
 class SsaBuilderTask extends CompilerTask {
   SsaBuilderTask(Compiler compiler) : super(compiler);
   String get name() => 'SSA builder';
 
   HGraph build(FunctionElement element, TreeElements elements) {
     return measure(() {
@@ skipping 593 matching lines @@
       case "|=":  push(new HBitOr(target, left, right)); break;
       case "&":
       case "&=":  push(new HBitAnd(target, left, right)); break;
       case "^":
       case "^=":  push(new HBitXor(target, left, right)); break;
       case "==":  push(new HEquals(target, left, right)); break;
       case "<":   push(new HLess(target, left, right)); break;
       case "<=":  push(new HLessEqual(target, left, right)); break;
       case ">":   push(new HGreater(target, left, right)); break;
       case ">=":  push(new HGreaterEqual(target, left, right)); break;
+      case "!=":
+        HEquals eq = new HEquals(target, left, right);
+        add(eq);
+        HBoolify bl = new HBoolify(eq);
+        add(bl);
+        push(new HNot(bl));
+        break;
       default: compiler.unimplemented("SsaBuilder.visitBinary");
     }
   }
 
   void generateGetter(Send send, Element element) {
     if (Elements.isStaticOrTopLevelField(element)) {
       push(new HStatic(element));
     } else if (Elements.isInstanceField(element)) {
       String methodName = compiler.namer.getterName(element.name);
       HInstruction receiver = new HThis();
@@ skipping 351 matching lines @@
 
   visitStringInterpolation(StringInterpolation node) {
     compiler.unimplemented('SsaBuilder.visitStringInterpolation', node: node);
   }
 
   visitStringInterpolationPart(StringInterpolationPart node) {
     compiler.unimplemented('SsaBuilder.visitStringInterpolationPart',
                            node: node);
   }
 }