// Copyright (c) 2016 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 SOURCE_OPT_IR_LOADER_H_

#define SOURCE_OPT_IR_LOADER_H_

#include <memory>

#include <string>

#include <vector>

#include "source/opt/basic_block.h"

#include "source/opt/instruction.h"

#include "source/opt/module.h"

#include "spirv-tools/libspirv.hpp"

namespace spvtools {

namespace opt {

// Loader class for constructing SPIR-V in-memory IR representation. Methods in

// this class are designed to work with the interface for spvBinaryParse() in

// libspirv.h so that we can leverage the syntax checks implemented behind it.

//

// The user is expected to call SetModuleHeader() to fill in the module's

// header, and then AddInstruction() for each decoded instruction, and finally

// EndModule() to finalize the module. The instructions processed in sequence

// by AddInstruction() should comprise a valid SPIR-V module.

class IrLoader {

 public:

  // Instantiates a builder to construct the given |module| gradually.

  // All internal messages will be communicated to the outside via the given

  // message |consumer|. This instance only keeps a reference to the |consumer|,

  // so the |consumer| should outlive this instance.

  IrLoader(const MessageConsumer& consumer, Module* m);

  // Sets the source name of the module.

  void SetSource(const std::string& src) { source_ = src; }

  Module* module() const { return module_; }

  // Sets the fields in the module's header to the given parameters.

  void SetModuleHeader(uint32_t magic, uint32_t version, uint32_t generator,

                       uint32_t bound, uint32_t reserved) {

    module_->SetHeader({magic, version, generator, bound, reserved});

  }

  // Adds an instruction to the module. Returns true if no error occurs. This

  // method will properly capture and store the data provided in |inst| so that

  // |inst| is no longer needed after returning.

  bool AddInstruction(const spv_parsed_instruction_t* inst);

  // Finalizes the module construction. This must be called after the module

  // header has been set and all instructions have been added.  This is

  // forgiving in the case of a missing terminator instruction on a basic block,

  // or a missing OpFunctionEnd.  Resolves internal bookkeeping.

  void EndModule();

  // Sets whether extra OpLine instructions should be injected to better

  // track line information.

  void SetExtraLineTracking(bool flag) { extra_line_tracking_ = flag; }

 private:

  // Consumer for communicating messages to outside.

  const MessageConsumer& consumer_;

  // The module to be built.

  Module* module_;

  // The source name of the module.

  std::string source_;

  // The last used instruction index.

  uint32_t inst_index_;

  // The current Function under construction.

  std::unique_ptr<Function> function_;

  // The current BasicBlock under construction.

  std::unique_ptr<BasicBlock> block_;

  // Line related debug instructions accumulated thus far.

  std::vector<Instruction> dbg_line_info_;

  // If doing extra line tracking, this is the line instruction that should be

  // applied to the next instruction.  Otherwise it always contains null.

  std::unique_ptr<Instruction> last_line_inst_;

  // The last DebugScope information that IrLoader::AddInstruction() handled.

  DebugScope last_dbg_scope_;

  // When true, do extra line information tracking: Additional OpLine

  // instructions will be injected to help track line info more robustly during

  // transformations.

  bool extra_line_tracking_ = true;

};

}  // namespace opt

}  // namespace spvtools

#endif  // SOURCE_OPT_IR_LOADER_H_