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

runtime/vm/flow_graph.h

 // 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.
 
 #ifndef RUNTIME_VM_FLOW_GRAPH_H_
 #define RUNTIME_VM_FLOW_GRAPH_H_
 
 #include "vm/bit_vector.h"
 #include "vm/growable_array.h"
 #include "vm/hash_map.h"
 #include "vm/intermediate_language.h"
 #include "vm/parser.h"
 #include "vm/thread.h"
 
 namespace dart {
 
-class BlockEffects;
 class FlowGraphBuilder;
 class ValueInliningContext;
 class VariableLivenessAnalysis;
 
 class BlockIterator : public ValueObject {
  public:
   explicit BlockIterator(const GrowableArray<BlockEntryInstr*>& block_order)
       : block_order_(block_order), current_(0) {}
 
   BlockIterator(const BlockIterator& other)
@@ skipping 173 matching lines @@
                   ZoneGrowableArray<Definition*>* inlining_parameters);
 
   // Verification methods for debugging.
   bool VerifyUseLists();
   bool VerifyRedefinitions();
 
   void DiscoverBlocks();
 
   void MergeBlocks();
 
-  // Compute information about effects occurring in different blocks and
-  // discover side-effect free paths.
-  void ComputeBlockEffects();
-  BlockEffects* block_effects() const { return block_effects_; }
-
   // Insert a redefinition of an original definition after prev and rename all
   // dominated uses of the original.  If an equivalent redefinition is already
   // present, nothing is inserted.
   // Returns the redefinition, if a redefinition was inserted, NULL otherwise.
   RedefinitionInstr* EnsureRedefinition(Instruction* prev,
                                         Definition* original,
                                         CompileType compile_type);
 
   // Remove the redefinition instructions inserted to inhibit code motion.
   void RemoveRedefinitions();
@@ skipping 172 matching lines @@
   const intptr_t num_non_copied_params_;
   GraphEntryInstr* graph_entry_;
   GrowableArray<BlockEntryInstr*> preorder_;
   GrowableArray<BlockEntryInstr*> postorder_;
   GrowableArray<BlockEntryInstr*> reverse_postorder_;
   GrowableArray<BlockEntryInstr*> optimized_block_order_;
   ConstantInstr* constant_null_;
   ConstantInstr* constant_dead_;
   ConstantInstr* constant_empty_context_;
 
-  BlockEffects* block_effects_;
   bool licm_allowed_;
 
   ZoneGrowableArray<BlockEntryInstr*>* loop_headers_;
   ZoneGrowableArray<BitVector*>* loop_invariant_loads_;
   ZoneGrowableArray<const LibraryPrefix*>* deferred_prefixes_;
   ZoneGrowableArray<TokenPosition>* await_token_positions_;
   DirectChainedHashMap<ConstantPoolTrait> constant_instr_pool_;
   BitVector* captured_parameters_;
 
   intptr_t inlining_id_;
@@ skipping 66 matching lines @@
 
   // Kill sets for each block.  They contain indices of variables that
   // are defined by this block.
   GrowableArray<BitVector*> kill_;
 
   // Live-in sets for each block.  They contain indices of variables
   // that are used by this block or its successors.
   GrowableArray<BitVector*> live_in_;
 };
 
-// Information about side effect free paths between blocks.
-class BlockEffects : public ZoneAllocated {
- public:
-  explicit BlockEffects(FlowGraph* flow_graph);
-
-  // Return true if the given instruction is not affected by anything between
-  // its current block and target block. Used by CSE to determine if
-  // a computation is available in the given block.
-  bool IsAvailableAt(Instruction* instr, BlockEntryInstr* block) const;
-
-  // Return true if the given instruction is not affected by anything between
-  // the given block and its current block. Used by LICM to determine if
-  // a computation can be moved to loop's preheader and remain available at
-  // its current location.
-  bool CanBeMovedTo(Instruction* instr, BlockEntryInstr* block) const;
-
- private:
-  // Returns true if from dominates to and all paths between from and to are
-  // free of side effects.
-  bool IsSideEffectFreePath(BlockEntryInstr* from, BlockEntryInstr* to) const;
-
-  // Per block sets of available blocks. Block A is available at the block B if
-  // and only if A dominates B and all paths from A to B are free of side
-  // effects.
-  GrowableArray<BitVector*> available_at_;
-};
-
 class DefinitionWorklist : public ValueObject {
  public:
   DefinitionWorklist(FlowGraph* flow_graph, intptr_t initial_capacity)
       : defs_(initial_capacity),
         contains_vector_(new BitVector(flow_graph->zone(),
                                        flow_graph->current_ssa_temp_index())) {}
 
   void Add(Definition* defn) {
     if (!Contains(defn)) {
       defs_.Add(defn);
@@ skipping 23 matching lines @@
   }
 
  private:
   GrowableArray<Definition*> defs_;
   BitVector* contains_vector_;
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_FLOW_GRAPH_H_