Work around buggy break in List.sort and optimize constant folding of negative values.

dart/frog/leg/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.
 
 class Interceptors {
   Compiler compiler;
   Interceptors(Compiler this.compiler);
 
   SourceString mapOperatorToMethodName(Operator op) {
     String name = op.source.stringValue;
@@ skipping 1284 matching lines @@
 
   void visitUnary(Send node, Operator op) {
     assert(node.argumentsNode is Prefix);
     visit(node.receiver);
     assert(op.token.kind !== PLUS_TOKEN);
     HInstruction operand = pop();
     HInstruction target =
         new HStatic(interceptors.getPrefixOperatorInterceptor(op));
     add(target);
     switch (op.source.stringValue) {
-      case "-": push(new HNegate(target, operand)); break;
+      case "-":
+        // TODO(kasperl): Avoid calling visit(node.receiver) above.
+        if ((operand is HLiteral) && (operand.value is double)) {
+          stack.add(graph.addNewLiteralDouble(-operand.value));
+        } else if ((operand is HLiteral) && (operand.value is int)) {
+          stack.add(graph.addNewLiteralInt(-operand.value));
+        } else {
+          push(new HNegate(target, operand));
+        }
+        break;
       case "~": push(new HBitNot(target, operand)); break;
       default: unreachable();
     }
   }
 
   void visitBinary(HInstruction left, Operator op, HInstruction right) {
     Element element = interceptors.getOperatorInterceptor(op);
     assert(element != null);
     HInstruction target = new HStatic(element);
     add(target);
@@ skipping 1042 matching lines @@
     // Normally, we would call [close] here. However, then we hit
     // another unimplemented feature: aborting loop body. Simply
     // calling [add] does not work as it asserts that the instruction
     // isn't a control flow instruction. So we inline parts of [add].
     current.addAfter(current.last, new HThrow(message));
     if (isExpression) {
       stack.add(graph.addNewLiteralNull());
     }
   }
 }