//===----------------------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This file contains SPIRV builtins needed for kernel invocations
/// (parallel_for).
///
//===----------------------------------------------------------------------===//

#ifndef _LIBSYCL___SPIRV_SPIRV_VARS
#define _LIBSYCL___SPIRV_SPIRV_VARS

#include <cstddef>
#include <cstdint>

// SPIR-V built-in variables mapped to function call.

__attribute__((const)) size_t __spirv_BuiltInGlobalInvocationId(int);
__attribute__((const)) size_t __spirv_BuiltInGlobalSize(int);
__attribute__((const)) size_t __spirv_BuiltInGlobalOffset(int);

namespace __spirv {

// Helper function templates to initialize and get vector component from SPIR-V
// built-in variables
#define __SPIRV_DEFINE_INIT_AND_GET_HELPERS(POSTFIX)                           \
  template <int ID> size_t get##POSTFIX();                                     \
  template <> inline size_t get##POSTFIX<0>() { return __spirv_##POSTFIX(0); } \
  template <> inline size_t get##POSTFIX<1>() { return __spirv_##POSTFIX(1); } \
  template <> inline size_t get##POSTFIX<2>() { return __spirv_##POSTFIX(2); } \
                                                                               \
  template <int Dim, class DstT> struct InitSizesST##POSTFIX;                  \
                                                                               \
  template <class DstT> struct InitSizesST##POSTFIX<1, DstT> {                 \
    static DstT initSize() { return {get##POSTFIX<0>()}; }                     \
  };                                                                           \
                                                                               \
  template <class DstT> struct InitSizesST##POSTFIX<2, DstT> {                 \
    static DstT initSize() { return {get##POSTFIX<1>(), get##POSTFIX<0>()}; }  \
  };                                                                           \
                                                                               \
  template <class DstT> struct InitSizesST##POSTFIX<3, DstT> {                 \
    static DstT initSize() {                                                   \
      return {get##POSTFIX<2>(), get##POSTFIX<1>(), get##POSTFIX<0>()};        \
    }                                                                          \
  };                                                                           \
                                                                               \
  template <int Dims, class DstT> DstT init##POSTFIX() {                       \
    return InitSizesST##POSTFIX<Dims, DstT>::initSize();                       \
  }

__SPIRV_DEFINE_INIT_AND_GET_HELPERS(BuiltInGlobalSize);
__SPIRV_DEFINE_INIT_AND_GET_HELPERS(BuiltInGlobalInvocationId)
__SPIRV_DEFINE_INIT_AND_GET_HELPERS(BuiltInGlobalOffset)

#undef __SPIRV_DEFINE_INIT_AND_GET_HELPERS

} // namespace __spirv

#endif // _LIBSYCL___SPIRV_SPIRV_VARS