llvm/mlir/lib/Bytecode/Encoding.h

//===- Encoding.h - MLIR binary format encoding information -----*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This header defines enum values describing the structure of MLIR bytecode
// files.
//
//===----------------------------------------------------------------------===//

#ifndef LIB_MLIR_BYTECODE_ENCODING_H
#define LIB_MLIR_BYTECODE_ENCODING_H

#include <cstdint>

namespace mlir {
namespace bytecode {
//===----------------------------------------------------------------------===//
// General constants
//===----------------------------------------------------------------------===//

enum {
  /// The minimum supported version of the bytecode.
  kMinSupportedVersion = 0,

  /// The current bytecode version.
  kVersion = 1,

  /// An arbitrary value used to fill alignment padding.
  kAlignmentByte = 0xCB,
};

//===----------------------------------------------------------------------===//
// Sections
//===----------------------------------------------------------------------===//

namespace Section {
enum ID : uint8_t {
  /// This section contains strings referenced within the bytecode.
  kString = 0,

  /// This section contains the dialects referenced within an IR module.
  kDialect = 1,

  /// This section contains the attributes and types referenced within an IR
  /// module.
  kAttrType = 2,

  /// This section contains the offsets for the attribute and types within the
  /// AttrType section.
  kAttrTypeOffset = 3,

  /// This section contains the list of operations serialized into the bytecode,
  /// and their nested regions/operations.
  kIR = 4,

  /// This section contains the resources of the bytecode.
  kResource = 5,

  /// This section contains the offsets of resources within the Resource
  /// section.
  kResourceOffset = 6,

  /// This section contains the versions of each dialect.
  kDialectVersions = 7,

  /// The total number of section types.
  kNumSections = 8,
};
} // namespace Section

//===----------------------------------------------------------------------===//
// IR Section
//===----------------------------------------------------------------------===//

/// This enum represents a mask of all of the potential components of an
/// operation. This mask is used when encoding an operation to indicate which
/// components are present in the bytecode.
namespace OpEncodingMask {
enum : uint8_t {
  // clang-format off
  kHasAttrs         = 0b00000001,
  kHasResults       = 0b00000010,
  kHasOperands      = 0b00000100,
  kHasSuccessors    = 0b00001000,
  kHasInlineRegions = 0b00010000,
  // clang-format on
};
} // namespace OpEncodingMask

} // namespace bytecode
} // namespace mlir

#endif