Compute Compiler.proxyConstant on demand.

pkg/compiler/lib/src/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.
 
 part of ssa;
 
 class SsaCodeGeneratorTask extends CompilerTask {
 
   final JavaScriptBackend backend;
   final SourceInformationStrategy sourceInformationFactory;
@@ skipping 2676 matching lines @@
       return pop();
     } else if (checkedType.containsOnlyBool(classWorld)) {
       // input is !bool
       checkBool(input, '!==', input.sourceInformation);
       return pop();
     } else if (checkedType.containsOnlyString(classWorld)) {
       // input is !string
       checkString(input, '!==', input.sourceInformation);
       return pop();
     }
-    compiler.internalError(input, 'Unexpected check.');
+    compiler.internalError(input, 'Unexpected check: $checkedType.');
     return null;
   }
 
   void visitTypeConversion(HTypeConversion node) {
     if (node.isArgumentTypeCheck || node.isReceiverTypeCheck) {
       ClassWorld classWorld = compiler.world;
       // An int check if the input is not int or null, is not
       // sufficient for doing an argument or receiver check.
       assert(compiler.trustTypeAnnotations ||
              !node.checkedType.containsOnlyInt(classWorld) ||
@@ skipping 155 matching lines @@
     }
     registry.registerStaticUse(helper);
     return backend.emitter.staticFunctionAccess(helper);
   }
 
   @override
   void visitRef(HRef node) {
     visit(node.value);
   }
 }