Implement code generation for === and !==.

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 Interceptors {
   Compiler compiler;
   Interceptors(Compiler this.compiler);
 
   SourceString mapOperatorToMethodName(Operator op) {
     String name = op.source.stringValue;
     if (name === '-') return const SourceString('neg');
     if (name === '+') return const SourceString('add');
     if (name === '-') return const SourceString('sub');
     if (name === '*') return const SourceString('mul');
     if (name === '/') return const SourceString('div');
     if (name === '~/') return const SourceString('tdiv');
     if (name === '%') return const SourceString('mod');
     if (name === '<<') return const SourceString('shl');
     if (name === '>>') return const SourceString('shr');
     if (name === '|') return const SourceString('or');
     if (name === '&') return const SourceString('and');
     if (name === '^') return const SourceString('xor');
     if (name === '<') return const SourceString('lt');
     if (name === '<=') return const SourceString('le');
     if (name === '>') return const SourceString('gt');
     if (name === '>=') return const SourceString('ge');
     if (name === '==') return const SourceString('eq');
     if (name === '!=') return const SourceString('eq');
+    if (name === '===') return const SourceString('eqq');
+    if (name === '!==') return const SourceString('eqq');
     if (name === '+=') return const SourceString('add');
     if (name === '-=') return const SourceString('sub');
     if (name === '*=') return const SourceString('mul');
     if (name === '/=') return const SourceString('div');
     if (name === '~/=') return const SourceString('tdiv');
     if (name === '%=') return const SourceString('mod');
     if (name === '<<=') return const SourceString('shl');
     if (name === '>>=') return const SourceString('shr');
     if (name === '|=') return const SourceString('or');
     if (name === '&=') return const SourceString('and');
@@ skipping 684 matching lines @@
       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 HIdentity(target, left, right));
+        break;
+      case "!==":
+        HIdentity eq = new HIdentity(target, left, right);
+        add(eq);
+        push(new HNot(eq));
+        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 ">=":
@@ skipping 485 matching lines @@
   }
 
   visitCatchBlock(CatchBlock node) {
     compiler.unimplemented('SsaBuilder.visitCatchBlock', node: node);
   }
 
   visitTypedef(Typedef node) {
     compiler.unimplemented('SsaBuilder.visitTypedef', node: node);
   }
 }