Use UnaryOperator and BinaryOperator in ConstantSystem.

pkg/compiler/lib/src/ssa/builder.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 SsaFunctionCompiler implements FunctionCompiler {
   SsaCodeGeneratorTask generator;
   SsaBuilderTask builder;
   SsaOptimizerTask optimizer;
@@ skipping 3131 matching lines @@
   }
 
   void visitUnarySend(ast.Send node, ast.Operator op) {
     assert(node.argumentsNode is ast.Prefix);
     visit(node.receiver);
     assert(!identical(op.token.kind, PLUS_TOKEN));
     HInstruction operand = pop();
 
     // See if we can constant-fold right away. This avoids rewrites later on.
     if (operand is HConstant) {
-      UnaryOperation operation = constantSystem.lookupUnary(op.source);
+      UnaryOperation operation = constantSystem.lookupUnary(
+          UnaryOperator.parse(op.source));
       HConstant constant = operand;
       ConstantValue folded = operation.fold(constant.constant);
       if (folded != null) {
         stack.add(graph.addConstant(folded, compiler));
         return;
       }
     }
 
     pushInvokeDynamic(node, elements.getSelector(node), [operand]);
   }
@@ skipping 3840 matching lines @@
     if (unaliased is TypedefType) throw 'unable to unalias $type';
     unaliased.accept(this, builder);
   }
 
   void visitDynamicType(DynamicType type, SsaBuilder builder) {
     JavaScriptBackend backend = builder.compiler.backend;
     ClassElement cls = backend.findHelper('DynamicRuntimeType');
     builder.push(new HDynamicType(type, new TypeMask.exact(cls, classWorld)));
   }
 }