Fix Range::Mul for fully non-positive ranges.

runtime/vm/constant_propagator.cc

 // Copyright (c) 2013, 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.
 
 #include "vm/constant_propagator.h"
 
 #include "vm/bit_vector.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/flow_graph_compiler.h"
 #include "vm/flow_graph_range_analysis.h"
@@ skipping 1494 matching lines @@
     graph_->DiscoverBlocks();
     // TODO(fschneider): Update dominator tree in place instead of recomputing.
     GrowableArray<BitVector*> dominance_frontier;
     graph_->ComputeDominators(&dominance_frontier);
   }
 }
 
 
 void ConstantPropagator::Transform() {
   if (FLAG_trace_constant_propagation) {
-    OS::Print("\n==== Before constant propagation ====\n");
-    FlowGraphPrinter printer(*graph_);
-    printer.PrintBlocks();
+    FlowGraphPrinter::PrintGraph("Before CP", graph_);
   }
 
   // We will recompute dominators, block ordering, block ids, block last
   // instructions, previous pointers, predecessors, etc. after eliminating
   // unreachable code.  We do not maintain those properties during the
   // transformation.
   for (BlockIterator b = graph_->reverse_postorder_iterator();
        !b.Done();
        b.Advance()) {
     BlockEntryInstr* block = b.Current();
@@ skipping 127 matching lines @@
       }
     }
   }
 
   graph_->DiscoverBlocks();
   graph_->MergeBlocks();
   GrowableArray<BitVector*> dominance_frontier;
   graph_->ComputeDominators(&dominance_frontier);
 
   if (FLAG_trace_constant_propagation) {
-    OS::Print("\n==== After constant propagation ====\n");
-    FlowGraphPrinter printer(*graph_);
-    printer.PrintBlocks();
+    FlowGraphPrinter::PrintGraph("After CP", graph_);
   }
 }
 
 }  // namespace dart