Revert "Refactoring if block-information."

lib/compiler/implementation/ssa/optimize.dart

 // Copyright (c) 2011, 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.
 
 interface OptimizationPhase {
   String get name();
   void visitGraph(HGraph graph);
 }
 
 class SsaOptimizerTask extends CompilerTask {
@@ skipping 461 matching lines @@
     computeChangesFlags(graph);
     moveLoopInvariantCode(graph);
     visitBasicBlock(graph.entry, new ValueSet());
   }
 
   void moveLoopInvariantCode(HGraph graph) {
     for (int i = graph.blocks.length - 1; i >= 0; i--) {
       HBasicBlock block = graph.blocks[i];
       if (block.isLoopHeader()) {
         int changesFlags = loopChangesFlags[block.id];
-        HLoopInformation info = block.blockInformation;
-        HBasicBlock last = info.getLastBackEdge();
+        HBasicBlock last = block.loopInformation.getLastBackEdge();
         for (int j = block.id; j <= last.id; j++) {
           moveLoopInvariantCodeFromBlock(graph.blocks[j], block, changesFlags);
         }
       }
     }
   }
 
   void moveLoopInvariantCodeFromBlock(HBasicBlock block,
                                       HBasicBlock loopHeader,
                                       int changesFlags) {
@@ skipping 219 matching lines @@
         }
       }
       if (!canBeMoved) continue;
 
       // This is safe because we are running after GVN.
       // TODO(ngeoffray): ensure GVN has been run.
       set_.add(current);
     }
   }
 }