Revert "Fix checkedInstructionOrNonGenerateAtUseSite."

sdk/lib/_internal/compiler/implementation/ssa/variable_allocator.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;
 
 /**
  * The [LiveRange] class covers a range where an instruction is live.
  */
 class LiveRange {
@@ skipping 211 matching lines @@
       markAsLiveInEnvironment(instruction.inputs[i], environment);
     }
   }
 
   // Returns the non-HCheck instruction, or the last [HCheck] in the
   // check chain that is not generate at use site.
   HInstruction checkedInstructionOrNonGenerateAtUseSite(HCheck check) {
     var checked = check.checkedInput;
     while (checked is HCheck) {
       HInstruction next = checked.checkedInput;
+      if (generateAtUseSite.contains(next)) break;
       checked = next;
-      if (!generateAtUseSite.contains(next)) break;
     }
     return checked;
   }
 
   void markAsLiveInEnvironment(HInstruction instruction,
                                LiveEnvironment environment) {
     if (generateAtUseSite.contains(instruction)) {
       markInputsAsLiveInEnvironment(instruction, environment);
     } else {
       environment.add(instruction, instructionId);
@@ skipping 449 matching lines @@
       if (!needsName(input)) {
         names.addAssignment(predecessor, input, phi);
       } else {
         names.addCopy(predecessor, input, phi);
       }
     }
 
     namer.allocateName(phi);
   }
 }