Avoid "=== true" inside code by calling a function that does this for us.

lib/compiler/implementation/ssa/codegen.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.
 
 class SsaCodeGeneratorTask extends CompilerTask {
   SsaCodeGeneratorTask(Compiler compiler) : super(compiler);
   String get name() => 'SSA code generator';
 
 
   String generateMethod(WorkItem work, HGraph graph) {
@@ skipping 109 matching lines @@
   final Map<int, String> names;
   final Set<String> usedNames;
   final Map<String, int> prefixes;
   final Set<HInstruction> generateAtUseSite;
   final Map<HPhi, String> logicalOperations;
   final Map<Element, ElementAction> breakAction;
   final Map<Element, ElementAction> continueAction;
   final Equivalence<HPhi> phiEquivalence;
 
   Element equalsNullElement;
+  Element boolifiedEqualsNullElement;
   int indent = 0;
   int expectedPrecedence = JSPrecedence.STATEMENT_PRECEDENCE;
   HGraph currentGraph;
   /**
    * Whether the code-generation should try to generate an expression
    * instead of a sequence of statements.
    */
   int generationState = STATE_STATEMENT;
   /**
    * While generating expressions, we can't insert variable declarations.
@@ skipping 29 matching lines @@
       continueAction = new Map<Element, ElementAction>(),
       phiEquivalence = new Equivalence<HPhi>() {
 
     for (final name in parameterNames.getValues()) {
       prefixes[name] = 0;
     }
 
     // Create a namespace for temporaries.
     prefixes[TEMPORARY_PREFIX] = 0;
 
-    equalsNullElement =
-        compiler.builder.interceptors.getEqualsNullInterceptor();
+    Interceptors interceptors = compiler.builder.interceptors;
+    equalsNullElement = interceptors.getEqualsNullInterceptor();
+    boolifiedEqualsNullElement =
+        interceptors.getBoolifiedVersionOf(equalsNullElement);
   }
 
   abstract visitTypeGuard(HTypeGuard node);
 
   abstract beginGraph(HGraph graph);
   abstract endGraph(HGraph graph);
 
   abstract beginLoop(HBasicBlock block);
   abstract endLoop(HBasicBlock block);
   abstract handleLoopCondition(HLoopBranch node);
@@ skipping 651 matching lines @@
     }
   }
 
   visitEquals(HEquals node) {
     if (node.builtin) {
       beginExpression(JSPrecedence.EQUALITY_PRECEDENCE);
       use(node.left, JSPrecedence.EQUALITY_PRECEDENCE);
       buffer.add(' === ');
       use(node.right, JSPrecedence.RELATIONAL_PRECEDENCE);
       endExpression(JSPrecedence.EQUALITY_PRECEDENCE);
-    } else if (node.element === equalsNullElement) {
+    } else if (node.element === equalsNullElement ||
+               node.element === boolifiedEqualsNullElement) {
       beginExpression(JSPrecedence.CALL_PRECEDENCE);
       use(node.target, JSPrecedence.CALL_PRECEDENCE);
       buffer.add('(');
       use(node.left, JSPrecedence.ASSIGNMENT_PRECEDENCE);
       buffer.add(')');
       endExpression(JSPrecedence.CALL_PRECEDENCE);
     } else {
       visitInvokeStatic(node);
     }
   }
@@ skipping 1216 matching lines @@
       startBailoutSwitch();
     }
   }
 
   void endLabeledBlock(HLabeledBlockInformation labeledBlockInfo) {
     if (labeledBlockInfo.body.start.hasGuards()) {
       endBailoutSwitch();
     }
   }
 }