SPIRV-Tools/source/opt/instruction_list.h

// Copyright (c) 2017 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef LIBSPIRV_OPT_INSTRUCTION_LIST_H_
#define LIBSPIRV_OPT_INSTRUCTION_LIST_H_

#include <cassert>
#include <functional>
#include <utility>
#include <vector>

#include "instruction.h"
#include "operand.h"
#include "util/ilist.h"

#include "spirv-tools/libspirv.h"
#include "spirv/1.2/spirv.h"

namespace spvtools {
namespace ir {

// This class is intended to be the container for Instructions.  This container
// owns the instructions that are in it.  When removing an Instruction from the
// list, the caller is assuming responsibility for deleting the storage.
//
// TODO: Because there are a number of other data structures that will want
// pointers to instruction, ownership should probably be moved to the module.
// Because of that I have not made the ownership passing in this class fully
// explicit.  For example, RemoveFromList takes ownership from the list, but
// does not return an std::unique_ptr to signal that.  When we fully decide on
// ownership, this will have to be fixed up one way or the other.
class InstructionList : public utils::IntrusiveList<Instruction> {
 public:
  InstructionList() = default;
  InstructionList(InstructionList&& that)
      : utils::IntrusiveList<Instruction>(std::move(that)) {}
  InstructionList& operator=(InstructionList&& that) {
    auto p = static_cast<utils::IntrusiveList<Instruction>*>(this);
    *p = std::move(that);
    return *this;
  }

  // Destroy this list and any instructions in the list.
  virtual ~InstructionList();

  class iterator : public utils::IntrusiveList<Instruction>::iterator {
   public:
    iterator(const utils::IntrusiveList<Instruction>::iterator& i)
        : utils::IntrusiveList<Instruction>::iterator(&*i) {}
    iterator(Instruction* i) : utils::IntrusiveList<Instruction>::iterator(i) {}

    // DEPRECATED: Please use MoveBefore with an InstructionList instead.
    //
    // Moves the nodes in |list| to the list that |this| points to.  The
    // positions of the nodes will be immediately before the element pointed to
    // by the iterator.  The return value will be an iterator pointing to the
    // first of the newly inserted elements.  Ownership of the elements in
    // |list| is now passed on to |*this|.
    iterator InsertBefore(std::vector<std::unique_ptr<Instruction>>&& list);

    // The node |i| will be inserted immediately before |this|. The return value
    // will be an iterator pointing to the newly inserted node.  The owner of
    // |*i| becomes |*this|
    iterator InsertBefore(std::unique_ptr<Instruction>&& i);
  };

  iterator begin() { return utils::IntrusiveList<Instruction>::begin(); }
  iterator end() { return utils::IntrusiveList<Instruction>::end(); }
  const_iterator begin() const {
    return utils::IntrusiveList<Instruction>::begin();
  }
  const_iterator end() const {
    return utils::IntrusiveList<Instruction>::end();
  }
};

}  // namespace ir
}  // namespace spvtools

#endif  // LIBSPIRV_OPT_INSTRUCTION_LIST_H_