Files
project_6/cccl_upstream/libcudacxx/codegen/generators/ld_st.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

408 lines
13 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) 2024 NVIDIA CORPORATION & AFFILIATES.
//
//===----------------------------------------------------------------------===//
#ifndef LD_ST_H
#define LD_ST_H
#include <format>
#include <string>
#include "definitions.h"
inline std::string semantic_ld_st(Semantic sem)
{
static std::map sem_map = {
std::pair{Semantic::Relaxed, ".relaxed"},
std::pair{Semantic::Release, ".release"},
std::pair{Semantic::Acquire, ".acquire"},
std::pair{Semantic::Volatile, ".volatile"},
};
return sem_map[sem];
}
inline std::string scope_ld_st(Semantic sem, Scope sco)
{
if (sem == Semantic::Volatile)
{
return "";
}
return scope(sco);
}
inline void FormatLoad(std::ostream& out)
{
out << R"XXX(
template <class _Fn, class _Sco>
static inline _CCCL_DEVICE void __cuda_atomic_load_memory_order_dispatch(_Fn &__cuda_load, int __memorder, _Sco) {
NV_DISPATCH_TARGET(
NV_PROVIDES_SM_70, (
switch (__memorder) {
case __ATOMIC_SEQ_CST: __cuda_atomic_fence(_Sco{}, __atomic_cuda_seq_cst{}); [[fallthrough]];
case __ATOMIC_CONSUME: [[fallthrough]];
case __ATOMIC_ACQUIRE: __cuda_load(__atomic_cuda_acquire{}); break;
case __ATOMIC_RELAXED: __cuda_load(__atomic_cuda_relaxed{}); break;
default: _CCCL_ASSERT(false, "invalid memory order");
}
),
NV_IS_DEVICE, (
switch (__memorder) {
case __ATOMIC_SEQ_CST: __cuda_atomic_membar(_Sco{}); [[fallthrough]];
case __ATOMIC_CONSUME: [[fallthrough]];
case __ATOMIC_ACQUIRE: __cuda_load(__atomic_cuda_volatile{}); __cuda_atomic_membar(_Sco{}); break;
case __ATOMIC_RELAXED: __cuda_load(__atomic_cuda_volatile{}); break;
default: _CCCL_ASSERT(false, "invalid memory order");
}
)
)
}
)XXX";
// Argument ID Reference
// 0 - Operand Type
// 1 - Operand Size
// 2 - Constraint
// 3 - Memory order
// 4 - Memory order semantic
// 5 - Scope tag
// 6 - Scope semantic
// 7 - Mmio tag
// 8 - Mmio semantic
constexpr auto asm_intrinsic_format_128 = R"XXX(
template <class _Type>
static inline _CCCL_DEVICE void __cuda_atomic_load(
const _Type* __ptr, _Type& __dst, {3}, __atomic_cuda_operand_{0}{1}, {5}, {7})
{{
static_assert(__cccl_ptx_isa >= 840 && (sizeof(_Type) == 16), "128b ld/st is not supported until PTX ISA version 840");
NV_DISPATCH_TARGET(
NV_PROVIDES_SM_70, (),
NV_ANY_TARGET, (__atomic_ldst_128b_unsupported_before_SM_70();)
)
asm volatile(R"YYY(
{{
.reg .b128 _d;
ld{8}{4}{6}.b128 _d,[%2];
mov.b128 {{%0, %1}}, _d;
}}
)YYY" : "=l"(__dst.__x),"=l"(__dst.__y) : "l"(__ptr) : "memory");
}})XXX";
constexpr auto asm_intrinsic_format = R"XXX(
template <class _Type>
static inline _CCCL_DEVICE void __cuda_atomic_load(
const _Type* __ptr, _Type& __dst, {3}, __atomic_cuda_operand_{0}{1}, {5}, {7})
{{ asm volatile("ld{8}{4}{6}.{0}{1} %0,[%1];" : "={2}"(__dst) : "l"(__ptr) : "memory"); }})XXX";
constexpr size_t supported_sizes[] = {
16,
32,
64,
128,
};
constexpr Operand supported_types[] = {
Operand::Bit,
Operand::Floating,
Operand::Unsigned,
Operand::Signed,
};
constexpr Semantic supported_semantics[] = {
Semantic::Acquire,
Semantic::Relaxed,
Semantic::Volatile,
};
constexpr Scope supported_scopes[] = {
Scope::CTA,
Scope::Cluster,
Scope::GPU,
Scope::System,
};
constexpr Mmio mmio_states[] = {
Mmio::Disabled,
Mmio::Enabled,
};
for (auto size : supported_sizes)
{
for (auto type : supported_types)
{
for (auto sem : supported_semantics)
{
for (auto sco : supported_scopes)
{
for (auto mm : mmio_states)
{
if (size == 16 && type == Operand::Floating)
{
continue;
}
if (size == 128 && type != Operand::Bit)
{
continue;
}
if ((mm == Mmio::Enabled) && ((sco != Scope::System) || (sem != Semantic::Relaxed)))
{
continue;
}
if (size == 128)
{
out << std::format(
asm_intrinsic_format_128,
/* 0 */ operand(type),
/* 1 */ size,
/* 2 */ constraints(type, size),
/* 3 */ semantic_tag(sem),
/* 4 */ semantic_ld_st(sem),
/* 5 */ scope_tag(sco),
/* 6 */ scope_ld_st(sem, sco),
/* 7 */ mmio_tag(mm),
/* 8 */ mmio(mm));
}
else
{
out << std::format(
asm_intrinsic_format,
/* 0 */ operand(type),
/* 1 */ size,
/* 2 */ constraints(type, size),
/* 3 */ semantic_tag(sem),
/* 4 */ semantic_ld_st(sem),
/* 5 */ scope_tag(sco),
/* 6 */ scope_ld_st(sem, sco),
/* 7 */ mmio_tag(mm),
/* 8 */ mmio(mm));
}
}
}
}
}
}
out << "\n"
<< R"XXX(
template <typename _Type, typename _Tag, typename _Sco, typename _Mmio>
struct __cuda_atomic_bind_load {
const _Type* __ptr;
_Type* __dst;
template <typename _Atomic_Memorder>
inline _CCCL_DEVICE void operator()(_Atomic_Memorder) {
__cuda_atomic_load(__ptr, *__dst, _Atomic_Memorder{}, _Tag{}, _Sco{}, _Mmio{});
}
};
template <class _Type, class _Sco>
static inline _CCCL_DEVICE void __atomic_load_cuda(const _Type* __ptr, _Type& __dst, int __memorder, _Sco)
{
using __proxy_t = typename __atomic_cuda_deduce_bitwise<_Type>::__type;
using __proxy_tag = typename __atomic_cuda_deduce_bitwise<_Type>::__tag;
const __proxy_t* __ptr_proxy = reinterpret_cast<const __proxy_t*>(__ptr);
__proxy_t* __dst_proxy = reinterpret_cast<__proxy_t*>(&__dst);
if (__cuda_load_weak_if_local(__ptr_proxy, __dst_proxy, sizeof(__proxy_t))) {{return;}}
__cuda_atomic_bind_load<__proxy_t, __proxy_tag, _Sco, __atomic_cuda_mmio_disable> __bound_load{__ptr_proxy, __dst_proxy};
__cuda_atomic_load_memory_order_dispatch(__bound_load, __memorder, _Sco{});
}
template <class _Type, class _Sco>
static inline _CCCL_DEVICE void __atomic_load_cuda(const _Type volatile* __ptr, _Type& __dst, int __memorder, _Sco)
{
using __proxy_t = typename __atomic_cuda_deduce_bitwise<_Type>::__type;
using __proxy_tag = typename __atomic_cuda_deduce_bitwise<_Type>::__tag;
const __proxy_t* __ptr_proxy = reinterpret_cast<const __proxy_t*>(const_cast<_Type*>(__ptr));
__proxy_t* __dst_proxy = reinterpret_cast<__proxy_t*>(&__dst);
if (__cuda_load_weak_if_local(__ptr_proxy, __dst_proxy, sizeof(__proxy_t))) {{return;}}
__cuda_atomic_bind_load<__proxy_t, __proxy_tag, _Sco, __atomic_cuda_mmio_disable> __bound_load{__ptr_proxy, __dst_proxy};
__cuda_atomic_load_memory_order_dispatch(__bound_load, __memorder, _Sco{});
}
)XXX";
}
inline void FormatStore(std::ostream& out)
{
out << R"XXX(
template <class _Fn, class _Sco>
static inline _CCCL_DEVICE void __cuda_atomic_store_memory_order_dispatch(_Fn &__cuda_store, int __memorder, _Sco) {
NV_DISPATCH_TARGET(
NV_PROVIDES_SM_70, (
switch (__memorder) {
case __ATOMIC_RELEASE: __cuda_store(__atomic_cuda_release{}); break;
case __ATOMIC_SEQ_CST: __cuda_atomic_fence(_Sco{}, __atomic_cuda_seq_cst{}); [[fallthrough]];
case __ATOMIC_RELAXED: __cuda_store(__atomic_cuda_relaxed{}); break;
default: _CCCL_ASSERT(false, "invalid memory order");
}
),
NV_IS_DEVICE, (
switch (__memorder) {
case __ATOMIC_RELEASE: [[fallthrough]];
case __ATOMIC_SEQ_CST: __cuda_atomic_membar(_Sco{}); [[fallthrough]];
case __ATOMIC_RELAXED: __cuda_store(__atomic_cuda_volatile{}); break;
default: _CCCL_ASSERT(false, "invalid memory order");
}
)
)
}
)XXX";
// Argument ID Reference
// 0 - Operand Type
// 1 - Operand Size
// 2 - Constraint
// 3 - Memory order
// 4 - Memory order semantic
// 5 - Scope tag
// 6 - Scope semantic
// 7 - Mmio tag
// 8 - Mmio semantic
constexpr auto asm_intrinsic_format_128 = R"XXX(
template <class _Type>
static inline _CCCL_DEVICE void __cuda_atomic_store(
_Type* __ptr, _Type& __val, {3}, __atomic_cuda_operand_{0}{1}, {5}, {7})
{{
static_assert(__cccl_ptx_isa >= 840 && (sizeof(_Type) == 16), "128b ld/st is not supported until PTX ISA version 840");
NV_DISPATCH_TARGET(
NV_PROVIDES_SM_70, (),
NV_ANY_TARGET, (__atomic_ldst_128b_unsupported_before_SM_70();)
)
asm volatile(R"YYY(
{{
.reg .b128 _v;
mov.b128 _v, {{%1, %2}};
st{8}{4}{6}.b128 [%0],_v;
}}
)YYY" :: "l"(__ptr), "l"(__val.__x),"l"(__val.__y) : "memory");
}})XXX";
constexpr auto asm_intrinsic_format = R"XXX(
template <class _Type>
static inline _CCCL_DEVICE void __cuda_atomic_store(
_Type* __ptr, _Type& __val, {3}, __atomic_cuda_operand_{0}{1}, {5}, {7})
{{ asm volatile("st{8}{4}{6}.{0}{1} [%0],%1;" :: "l"(__ptr), "{2}"(__val) : "memory"); }})XXX";
constexpr size_t supported_sizes[] = {
16,
32,
64,
128,
};
constexpr Operand supported_types[] = {
Operand::Bit,
};
constexpr Semantic supported_semantics[] = {
Semantic::Release,
Semantic::Relaxed,
Semantic::Volatile,
};
constexpr Scope supported_scopes[] = {
Scope::CTA,
Scope::Cluster,
Scope::GPU,
Scope::System,
};
constexpr Mmio mmio_states[] = {
Mmio::Disabled,
Mmio::Enabled,
};
for (auto size : supported_sizes)
{
for (auto type : supported_types)
{
for (auto sem : supported_semantics)
{
for (auto sco : supported_scopes)
{
for (auto mm : mmio_states)
{
if (size == 16 && type == Operand::Floating)
{
continue;
}
if (size == 128 && type != Operand::Bit)
{
continue;
}
if ((mm == Mmio::Enabled) && ((sco != Scope::System) || (sem != Semantic::Relaxed)))
{
continue;
}
if (size == 128)
{
out << std::format(
asm_intrinsic_format_128,
/* 0 */ operand(type),
/* 1 */ size,
/* 2 */ constraints(type, size),
/* 3 */ semantic_tag(sem),
/* 4 */ semantic_ld_st(sem),
/* 5 */ scope_tag(sco),
/* 6 */ scope_ld_st(sem, sco),
/* 7 */ mmio_tag(mm),
/* 8 */ mmio(mm));
}
else
{
out << std::format(
asm_intrinsic_format,
/* 0 */ operand(type),
/* 1 */ size,
/* 2 */ constraints(type, size),
/* 3 */ semantic_tag(sem),
/* 4 */ semantic_ld_st(sem),
/* 5 */ scope_tag(sco),
/* 6 */ scope_ld_st(sem, sco),
/* 7 */ mmio_tag(mm),
/* 8 */ mmio(mm));
}
}
}
}
}
}
out << "\n"
<< R"XXX(
template <typename _Type, typename _Tag, typename _Sco, typename _Mmio>
struct __cuda_atomic_bind_store {
_Type* __ptr;
_Type* __val;
template <typename _Atomic_Memorder>
inline _CCCL_DEVICE void operator()(_Atomic_Memorder) {
__cuda_atomic_store(__ptr, *__val, _Atomic_Memorder{}, _Tag{}, _Sco{}, _Mmio{});
}
};
template <class _Type, class _Sco>
static inline _CCCL_DEVICE void __atomic_store_cuda(_Type* __ptr, _Type& __val, int __memorder, _Sco)
{
using __proxy_t = typename __atomic_cuda_deduce_bitwise<_Type>::__type;
using __proxy_tag = typename __atomic_cuda_deduce_bitwise<_Type>::__tag;
__proxy_t* __ptr_proxy = reinterpret_cast<__proxy_t*>(__ptr);
__proxy_t* __val_proxy = reinterpret_cast<__proxy_t*>(&__val);
if (__cuda_store_weak_if_local(__ptr_proxy, __val_proxy, sizeof(__proxy_t))) {{return;}}
__cuda_atomic_bind_store<__proxy_t, __proxy_tag, _Sco, __atomic_cuda_mmio_disable> __bound_store{__ptr_proxy, __val_proxy};
__cuda_atomic_store_memory_order_dispatch(__bound_store, __memorder, _Sco{});
}
template <class _Type, class _Sco>
static inline _CCCL_DEVICE void __atomic_store_cuda(volatile _Type* __ptr, _Type& __val, int __memorder, _Sco)
{
using __proxy_t = typename __atomic_cuda_deduce_bitwise<_Type>::__type;
using __proxy_tag = typename __atomic_cuda_deduce_bitwise<_Type>::__tag;
__proxy_t* __ptr_proxy = reinterpret_cast<__proxy_t*>(const_cast<_Type*>(__ptr));
__proxy_t* __val_proxy = reinterpret_cast<__proxy_t*>(&__val);
if (__cuda_store_weak_if_local(__ptr_proxy, __val_proxy, sizeof(__proxy_t))) {{return;}}
__cuda_atomic_bind_store<__proxy_t, __proxy_tag, _Sco, __atomic_cuda_mmio_disable> __bound_store{__ptr_proxy, __val_proxy};
__cuda_atomic_store_memory_order_dispatch(__bound_store, __memorder, _Sco{});
}
)XXX";
}
#endif // LD_ST_H