Skip to content

[OpenMP] Update atomic helpers to just use headers #122185

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Jan 9, 2025
Merged

[OpenMP] Update atomic helpers to just use headers #122185

Show file tree
Hide file tree
Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
6f982cb
[OpenMP] Update atomic helpers to just use headers
jhuber6 Jan 8, 2025
5b7c52b
update
jhuber6 Jan 8, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion offload/DeviceRTL/CMakeLists.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -99,7 +99,7 @@ set(bc_flags -c -foffload-lto -std=c++17 -fvisibility=hidden
${clang_opt_flags} --offload-device-only
-nocudalib -nogpulib -nogpuinc -nostdlibinc
-fopenmp -fopenmp-cuda-mode
-Wno-unknown-cuda-version
-Wno-unknown-cuda-version -Wno-openmp-target
Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

This is noise, for some reason it thinks that the static constexpr variables aren't on the device (they are)`. Ideally OpenMP will be removed altogether soon enough.

-DOMPTARGET_DEVICE_RUNTIME
-I${include_directory}
-I${devicertl_base_directory}/../include
Expand Down
41 changes: 41 additions & 0 deletions offload/DeviceRTL/include/DeviceUtils.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -19,6 +19,47 @@

namespace utils {

template <typename T> struct type_identity {
using type = T;
};

template <typename T, T v> struct integral_constant {
inline static constexpr T value = v;
};

/// Freestanding SFINAE helpers.
template <class T> struct remove_cv : type_identity<T> {};
template <class T> struct remove_cv<const T> : type_identity<T> {};
template <class T> struct remove_cv<volatile T> : type_identity<T> {};
template <class T> struct remove_cv<const volatile T> : type_identity<T> {};
template <class T> using remove_cv_t = typename remove_cv<T>::type;

using true_type = integral_constant<bool, true>;
using false_type = integral_constant<bool, false>;

template <typename T, typename U> struct is_same : false_type {};
template <typename T> struct is_same<T, T> : true_type {};
template <typename T, typename U>
inline constexpr bool is_same_v = is_same<T, U>::value;

template <typename T> struct is_floating_point {
inline static constexpr bool value =
is_same_v<remove_cv<T>, float> || is_same_v<remove_cv<T>, double>;
};
template <typename T>
inline constexpr bool is_floating_point_v = is_floating_point<T>::value;

template <bool B, typename T = void> struct enable_if;
template <typename T> struct enable_if<true, T> : type_identity<T> {};
template <bool B, typename T = void>
using enable_if_t = typename enable_if<B, T>::type;

template <class T> struct remove_addrspace : type_identity<T> {};
template <class T, int N>
struct remove_addrspace<T [[clang::address_space(N)]]> : type_identity<T> {};
template <class T>
using remove_addrspace_t = typename remove_addrspace<T>::type;

/// Return the value \p Var from thread Id \p SrcLane in the warp if the thread
/// is identified by \p Mask.
int32_t shuffle(uint64_t Mask, int32_t Var, int32_t SrcLane, int32_t Width);
Expand Down
169 changes: 123 additions & 46 deletions offload/DeviceRTL/include/Synchronization.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -13,9 +13,11 @@
#define OMPTARGET_DEVICERTL_SYNCHRONIZATION_H

#include "DeviceTypes.h"
#include "DeviceUtils.h"

namespace ompx {
#pragma omp begin declare target device_type(nohost)

namespace ompx {
namespace atomic {

enum OrderingTy {
Expand Down Expand Up @@ -48,51 +50,124 @@ uint32_t inc(uint32_t *Addr, uint32_t V, OrderingTy Ordering,
/// result is stored in \p *Addr;
/// {

#define ATOMIC_COMMON_OP(TY) \
TY add(TY *Addr, TY V, OrderingTy Ordering); \
TY mul(TY *Addr, TY V, OrderingTy Ordering); \
TY load(TY *Addr, OrderingTy Ordering); \
void store(TY *Addr, TY V, OrderingTy Ordering); \
bool cas(TY *Addr, TY ExpectedV, TY DesiredV, OrderingTy OrderingSucc, \
OrderingTy OrderingFail);

#define ATOMIC_FP_ONLY_OP(TY) \
TY min(TY *Addr, TY V, OrderingTy Ordering); \
TY max(TY *Addr, TY V, OrderingTy Ordering);

#define ATOMIC_INT_ONLY_OP(TY) \
TY min(TY *Addr, TY V, OrderingTy Ordering); \
TY max(TY *Addr, TY V, OrderingTy Ordering); \
TY bit_or(TY *Addr, TY V, OrderingTy Ordering); \
TY bit_and(TY *Addr, TY V, OrderingTy Ordering); \
TY bit_xor(TY *Addr, TY V, OrderingTy Ordering);

#define ATOMIC_FP_OP(TY) \
ATOMIC_FP_ONLY_OP(TY) \
ATOMIC_COMMON_OP(TY)

#define ATOMIC_INT_OP(TY) \
ATOMIC_INT_ONLY_OP(TY) \
ATOMIC_COMMON_OP(TY)

// This needs to be kept in sync with the header. Also the reason we don't use
// templates here.
ATOMIC_INT_OP(int8_t)
ATOMIC_INT_OP(int16_t)
ATOMIC_INT_OP(int32_t)
ATOMIC_INT_OP(int64_t)
ATOMIC_INT_OP(uint8_t)
ATOMIC_INT_OP(uint16_t)
ATOMIC_INT_OP(uint32_t)
ATOMIC_INT_OP(uint64_t)
ATOMIC_FP_OP(float)
ATOMIC_FP_OP(double)

#undef ATOMIC_INT_ONLY_OP
#undef ATOMIC_FP_ONLY_OP
#undef ATOMIC_COMMON_OP
#undef ATOMIC_INT_OP
#undef ATOMIC_FP_OP
template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
bool cas(Ty *Address, V ExpectedV, V DesiredV, atomic::OrderingTy OrderingSucc,
atomic::OrderingTy OrderingFail) {
return __scoped_atomic_compare_exchange(Address, &ExpectedV, &DesiredV, false,
OrderingSucc, OrderingFail,
__MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V add(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_add(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V load(Ty *Address, atomic::OrderingTy Ordering) {
return add(Address, Ty(0), Ordering);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
void store(Ty *Address, V Val, atomic::OrderingTy Ordering) {
__scoped_atomic_store_n(Address, Val, Ordering, __MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V mul(Ty *Address, V Val, atomic::OrderingTy Ordering) {
Ty TypedCurrentVal, TypedResultVal, TypedNewVal;
bool Success;
do {
TypedCurrentVal = atomic::load(Address, Ordering);
TypedNewVal = TypedCurrentVal * Val;
Success = atomic::cas(Address, TypedCurrentVal, TypedNewVal, Ordering,
atomic::relaxed);
} while (!Success);
return TypedResultVal;
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<!utils::is_floating_point_v<V>, V>
max(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_max(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<utils::is_same_v<V, float>, V>
max(Ty *Address, V Val, atomic::OrderingTy Ordering) {
if (Val >= 0)
return max((int32_t *)Address, utils::convertViaPun<int32_t>(Val),
Ordering);
return min((uint32_t *)Address, utils::convertViaPun<uint32_t>(Val),
Ordering);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<utils::is_same_v<V, double>, V>
max(Ty *Address, V Val, atomic::OrderingTy Ordering) {
if (Val >= 0)
return max((int64_t *)Address, utils::convertViaPun<int64_t>(Val),
Ordering);
return min((uint64_t *)Address, utils::convertViaPun<uint64_t>(Val),
Ordering);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<!utils::is_floating_point_v<V>, V>
min(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_min(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

// TODO: Implement this with __atomic_fetch_max and remove the duplication.
template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<utils::is_same_v<V, float>, V>
min(Ty *Address, V Val, atomic::OrderingTy Ordering) {
if (Val >= 0)
return min((int32_t *)Address, utils::convertViaPun<int32_t>(Val),
Ordering);
return max((uint32_t *)Address, utils::convertViaPun<uint32_t>(Val),
Ordering);
}

// TODO: Implement this with __atomic_fetch_max and remove the duplication.
template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
utils::enable_if_t<utils::is_same_v<V, double>, V>
min(Ty *Address, utils::remove_addrspace_t<Ty> Val,
atomic::OrderingTy Ordering) {
if (Val >= 0)
return min((int64_t *)Address, utils::convertViaPun<int64_t>(Val),
Ordering);
return max((uint64_t *)Address, utils::convertViaPun<uint64_t>(Val),
Ordering);
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I believe these were, and are, missing a convertViaPun on the return value.

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I copied what was there, I can add it, guessing it should go to float or double?

}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V bit_or(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_or(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V bit_and(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_and(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

template <typename Ty, typename V = utils::remove_addrspace_t<Ty>>
V bit_xor(Ty *Address, V Val, atomic::OrderingTy Ordering) {
return __scoped_atomic_fetch_xor(Address, Val, Ordering,
__MEMORY_SCOPE_DEVICE);
}

static inline uint32_t atomicExchange(uint32_t *Address, uint32_t Val,
atomic::OrderingTy Ordering) {
uint32_t R;
__scoped_atomic_exchange(Address, &Val, &R, Ordering, __MEMORY_SCOPE_DEVICE);
return R;
}

///}

Expand Down Expand Up @@ -145,4 +220,6 @@ void system(atomic::OrderingTy Ordering);

} // namespace ompx

#pragma omp end declare target

#endif
Loading
Loading