[vm] Cleanup Instruction::Dependencies(), EffectSet, BlockEffects

runtime/vm/flow_graph_range_analysis.cc

 // Copyright (c) 2014, 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/flow_graph_range_analysis.h"
 
 #include "vm/bit_vector.h"
 #include "vm/il_printer.h"
 
 namespace dart {
@@ skipping 455 matching lines @@
     // bottom element to indicate that the range was not computed *yet*.
     return &int64_range_;
   }
 
   return range;
 }
 
 static bool AreEqualDefinitions(Definition* a, Definition* b) {
   a = UnwrapConstraint(a);
   b = UnwrapConstraint(b);
-  return (a == b) ||
-         (a->AllowsCSE() && a->Dependencies().IsNone() && b->AllowsCSE() &&
-          b->Dependencies().IsNone() && a->Equals(b));
+  return (a == b) || (a->AllowsCSE() && b->AllowsCSE() && a->Equals(b));
 }
 
 static bool DependOnSameSymbol(const RangeBoundary& a, const RangeBoundary& b) {
   return a.IsSymbol() && b.IsSymbol() &&
          AreEqualDefinitions(a.symbol(), b.symbol());
 }
 
 // Given the current range of a phi and a newly computed range check
 // if it is growing towards negative infinity, if it does widen it to
 // MinSmi.
@@ skipping 2470 matching lines @@
       return max.offset() < canonical_length.offset();
     }
   } while (CanonicalizeMaxBoundary(&max) ||
            CanonicalizeMinBoundary(&canonical_length));
 
   // Failed to prove that maximum is bounded with array length.
   return false;
 }
 
 }  // namespace dart