WIP: Compute constant expressions in resolution.

pkg/compiler/lib/src/ssa/nodes.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;
 
 abstract class HVisitor<R> {
   R visitAdd(HAdd node);
   R visitAwait(HAwait node);
   R visitBitAnd(HBitAnd node);
@@ skipping 156 matching lines @@
   HBasicBlock addNewLoopHeaderBlock(JumpTarget target,
                                     List<LabelDefinition> labels) {
     HBasicBlock result = addNewBlock();
     result.loopInformation =
         new HLoopInformation(result, target, labels);
     return result;
   }
 
   HConstant addConstant(ConstantValue constant, Compiler compiler,
                         {SourceInformation sourceInformation}) {
+    if (!constant.isConstant) {
+      constant = compiler.backend.constantSystem.createNull();
+    }
     HConstant result = constants[constant];
     // TODO(johnniwinther): Support source information per constant reference.
     if (result == null) {
       TypeMask type = computeTypeMask(compiler, constant);
       result = new HConstant.internal(constant, type)
           ..sourceInformation = sourceInformation;
       entry.addAtExit(result);
       constants[constant] = result;
     } else if (result.block == null) {
       // The constant was not used anymore.
@@ skipping 3140 matching lines @@
 class HDynamicType extends HRuntimeType {
   HDynamicType(DynamicType dartType, TypeMask instructionType)
       : super(const <HInstruction>[], dartType, instructionType);
 
   accept(HVisitor visitor) => visitor.visitDynamicType(this);
 
   int typeCode() => HInstruction.DYNAMIC_TYPE_TYPECODE;
 
   bool typeEquals(HInstruction other) => other is HDynamicType;
 }