Files
project_6/cccl_upstream/libcudacxx/include/cuda/__bit/bitfield.h
EngineX CI 56fd68e7dd [INFRA] Import NVIDIA/CCCL upstream as optimization reference library
CCCL (CUDA C++ Core Libraries) provides:
- CUB: device/block/warp-level GPU primitives (reduce, scan, sort, topk)
- Thrust: high-level parallel algorithms (transform_reduce, sort, scan)
- libcudacxx: CUDA C++ standard library (atomics, barriers, memory)
- cudax: experimental features (memory resources, allocators)
- Tuning policies: per-SM hardware-specific algorithm parameters

Competition optimization vectors mapped to CCCL:
- Output TPS (83% weight): warp_reduce, block_reduce, device_topk
- Input TPS (14% weight): device_scan, block_load, prefetch
- Cache TPS (3% weight): prefix caching strategy patterns
- Memory (0.9 util): pooled/cached/buddy allocators

Source: https://github.com/NVIDIA/cccl (shallow clone, HEAD only)
License: Apache-2.0
2026-07-30 09:35:51 +00:00

130 lines
5.1 KiB
C++

//===----------------------------------------------------------------------===//
//
// Part of libcu++, the C++ Standard Library for your entire system,
// 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
// SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES.
//
//===----------------------------------------------------------------------===//
#ifndef _CUDA___BIT_BITFILED_INSERT_EXTRACT_H
#define _CUDA___BIT_BITFILED_INSERT_EXTRACT_H
#include <cuda/std/detail/__config>
#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
# pragma GCC system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
# pragma clang system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
# pragma system_header
#endif // no system header
#include <cuda/__bit/bitmask.h>
#include <cuda/std/__bit/shl.h>
#include <cuda/std/__bit/shr.h>
#include <cuda/std/__limits/numeric_limits.h>
#include <cuda/std/__type_traits/conditional.h>
#include <cuda/std/__type_traits/is_unsigned_integer.h>
#include <cuda/std/cstdint>
#include <cuda/std/limits>
#include <cuda/std/__cccl/prologue.h>
_CCCL_BEGIN_NAMESPACE_CUDA
#if !_CCCL_TILE_COMPILATION() // error: asm statement is unsupported in tile code
# if __cccl_ptx_isa >= 200
[[nodiscard]]
_CCCL_DEVICE_API inline uint32_t __bfi(uint32_t __dest, uint32_t __source, int __start, int __width) noexcept
{
asm("bfi.b32 %0, %1, %2, %3, %4;" : "=r"(__dest) : "r"(__source), "r"(__dest), "r"(__start), "r"(__width));
return __dest;
}
[[nodiscard]] _CCCL_DEVICE_API inline uint64_t
__bfi(uint64_t __dest, uint64_t __source, int __start, int __width) noexcept
{
asm("bfi.b64 %0, %1, %2, %3, %4;" : "=l"(__dest) : "l"(__source), "l"(__dest), "r"(__start), "r"(__width));
return __dest;
}
[[nodiscard]] _CCCL_DEVICE_API inline uint32_t __bfe(uint32_t __value, int __start, int __width) noexcept
{
uint32_t __ret;
asm("bfe.u32 %0, %1, %2, %3;" : "=r"(__ret) : "r"(__value), "r"(__start), "r"(__width));
return __ret;
}
[[nodiscard]] _CCCL_DEVICE_API inline uint64_t __bfe(uint64_t __value, int __start, int __width) noexcept
{
uint64_t __ret;
asm("bfe.u64 %0, %1, %2, %3;" : "=l"(__ret) : "l"(__value), "r"(__start), "r"(__width));
return __ret;
}
# endif // __cccl_ptx_isa >= 200
#endif // !_CCCL_TILE_COMPILATION()
template <typename _Tp>
[[nodiscard]]
_CCCL_API constexpr _Tp bitfield_insert(const _Tp __dest, const _Tp __source, int __start, int __width) noexcept
{
static_assert(::cuda::std::__cccl_is_cv_unsigned_integer_v<_Tp>, "bitfield_insert() requires unsigned integer types");
[[maybe_unused]] constexpr auto __digits = ::cuda::std::numeric_limits<_Tp>::digits;
_CCCL_ASSERT(__width >= 0 && __width <= __digits, "width out of range");
_CCCL_ASSERT(__start >= 0 && __start <= __digits, "start position out of range");
_CCCL_ASSERT(__start + __width <= __digits, "start position + width out of range");
#if !_CCCL_TILE_COMPILATION() // error: asm statement is unsupported in tile code
_CCCL_IF_NOT_CONSTEVAL_DEFAULT
{
if constexpr (sizeof(_Tp) <= sizeof(uint64_t))
{
// clang-format off
NV_DISPATCH_TARGET( // all SM < 70
NV_PROVIDES_SM_70, (;),
NV_IS_DEVICE, (using _Up = ::cuda::std::_If<sizeof(_Tp) <= sizeof(uint32_t), uint32_t, uint64_t>;
return ::cuda::__bfi(static_cast<_Up>(__dest), static_cast<_Up>(__source),
__start, __width);))
// clang-format on
}
}
#endif // !_CCCL_TILE_COMPILATION()
auto __mask = ::cuda::bitmask<_Tp>(__start, __width);
return (::cuda::std::shl(__source, static_cast<unsigned>(__start)) & __mask) | (__dest & ~__mask);
}
template <typename _Tp>
[[nodiscard]] _CCCL_API constexpr _Tp bitfield_extract(const _Tp __value, int __start, int __width) noexcept
{
static_assert(::cuda::std::__cccl_is_cv_unsigned_integer_v<_Tp>,
"bitfield_extract() requires unsigned integer types");
[[maybe_unused]] constexpr auto __digits = ::cuda::std::numeric_limits<_Tp>::digits;
_CCCL_ASSERT(__width >= 0 && __width <= __digits, "width out of range");
_CCCL_ASSERT(__start >= 0 && __start <= __digits, "start position out of range");
_CCCL_ASSERT(__start + __width <= __digits, "start position + width out of range");
#if !_CCCL_TILE_COMPILATION() // error: asm statement is unsupported in tile code
_CCCL_IF_NOT_CONSTEVAL_DEFAULT
{
if constexpr (sizeof(_Tp) <= sizeof(uint32_t))
{
// clang-format off
NV_DISPATCH_TARGET( // all SM < 70
NV_PROVIDES_SM_70, (;),
NV_IS_DEVICE, (using _Up = ::cuda::std::_If<sizeof(_Tp) <= sizeof(uint32_t), uint32_t, uint64_t>;
return ::cuda::__bfe(static_cast<_Up>(__value), __start, __width);))
// clang-format on
}
}
#endif // !_CCCL_TILE_COMPILATION()
return ::cuda::std::shr(__value, static_cast<unsigned>(__start)) & ::cuda::bitmask<_Tp>(0, __width);
}
_CCCL_END_NAMESPACE_CUDA
#include <cuda/std/__cccl/epilogue.h>
#endif // _CUDA___BIT_BITFILED_INSERT_EXTRACT_H