Move BFloat16.h to headeronly (#159412)

Pull Request resolved: https://github.com/pytorch/pytorch/pull/159412
Approved by: https://github.com/desertfire
This commit is contained in:
Jane Xu
2025-07-30 13:41:09 -07:00
committed by PyTorch MergeBot
parent e7cc42df58
commit c57382a493
5 changed files with 488 additions and 465 deletions

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@ -1,340 +1 @@
#pragma once
#include <c10/macros/Macros.h>
#include <c10/util/bit_cast.h>
#include <limits>
C10_CLANG_DIAGNOSTIC_PUSH()
#if C10_CLANG_HAS_WARNING("-Wimplicit-int-float-conversion")
C10_CLANG_DIAGNOSTIC_IGNORE("-Wimplicit-int-float-conversion")
#endif
#if defined(CL_SYCL_LANGUAGE_VERSION)
#include <CL/sycl.hpp> // for SYCL 1.2.1
#elif defined(SYCL_LANGUAGE_VERSION)
#include <sycl/sycl.hpp> // for SYCL 2020
#endif
namespace c10 {
/// Constructors
inline C10_HOST_DEVICE BFloat16::BFloat16(float value)
:
#if defined(__CUDACC__) && !defined(USE_ROCM) && defined(__CUDA_ARCH__) && \
__CUDA_ARCH__ >= 800
x(__bfloat16_as_ushort(__float2bfloat16(value)))
#elif defined(__SYCL_DEVICE_ONLY__) && \
defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
x(c10::bit_cast<uint16_t>(sycl::ext::oneapi::bfloat16(value)))
#else
// RNE by default
x(detail::round_to_nearest_even(value))
#endif
{
}
/// Implicit conversions
inline C10_HOST_DEVICE BFloat16::operator float() const {
#if defined(__CUDACC__) && !defined(USE_ROCM)
return __bfloat162float(*reinterpret_cast<const __nv_bfloat16*>(&x));
#elif defined(__SYCL_DEVICE_ONLY__) && \
defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
return float(*reinterpret_cast<const sycl::ext::oneapi::bfloat16*>(&x));
#else
return detail::f32_from_bits(x);
#endif
}
#if defined(__CUDACC__) && !defined(USE_ROCM)
inline C10_HOST_DEVICE BFloat16::BFloat16(const __nv_bfloat16& value) {
x = *reinterpret_cast<const unsigned short*>(&value);
}
inline C10_HOST_DEVICE BFloat16::operator __nv_bfloat16() const {
return *reinterpret_cast<const __nv_bfloat16*>(&x);
}
#endif
#if defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
inline C10_HOST_DEVICE BFloat16::BFloat16(
const sycl::ext::oneapi::bfloat16& value) {
x = *reinterpret_cast<const unsigned short*>(&value);
}
inline C10_HOST_DEVICE BFloat16::operator sycl::ext::oneapi::bfloat16() const {
return *reinterpret_cast<const sycl::ext::oneapi::bfloat16*>(&x);
}
#endif
// CUDA intrinsics
#if defined(__CUDACC__) || defined(__HIPCC__)
inline C10_DEVICE BFloat16 __ldg(const BFloat16* ptr) {
#if !defined(USE_ROCM) && defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 800
return __ldg(reinterpret_cast<const __nv_bfloat16*>(ptr));
#else
return *ptr;
#endif
}
#endif
/// Arithmetic
inline C10_HOST_DEVICE BFloat16
operator+(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) + static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16
operator-(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) - static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16
operator*(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) * static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(const BFloat16& a, const BFloat16& b)
__ubsan_ignore_float_divide_by_zero__ {
return static_cast<float>(a) / static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(const BFloat16& a) {
return -static_cast<float>(a);
}
inline C10_HOST_DEVICE BFloat16& operator+=(BFloat16& a, const BFloat16& b) {
a = a + b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator-=(BFloat16& a, const BFloat16& b) {
a = a - b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator*=(BFloat16& a, const BFloat16& b) {
a = a * b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator/=(BFloat16& a, const BFloat16& b) {
a = a / b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator|(BFloat16& a, const BFloat16& b) {
a.x = a.x | b.x;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator^(BFloat16& a, const BFloat16& b) {
a.x = a.x ^ b.x;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator&(BFloat16& a, const BFloat16& b) {
a.x = a.x & b.x;
return a;
}
/// Arithmetic with floats
inline C10_HOST_DEVICE float operator+(BFloat16 a, float b) {
return static_cast<float>(a) + b;
}
inline C10_HOST_DEVICE float operator-(BFloat16 a, float b) {
return static_cast<float>(a) - b;
}
inline C10_HOST_DEVICE float operator*(BFloat16 a, float b) {
return static_cast<float>(a) * b;
}
inline C10_HOST_DEVICE float operator/(BFloat16 a, float b) {
return static_cast<float>(a) / b;
}
inline C10_HOST_DEVICE float operator+(float a, BFloat16 b) {
return a + static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator-(float a, BFloat16 b) {
return a - static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator*(float a, BFloat16 b) {
return a * static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator/(float a, BFloat16 b) {
return a / static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator+=(float& a, const BFloat16& b) {
return a += static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator-=(float& a, const BFloat16& b) {
return a -= static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator*=(float& a, const BFloat16& b) {
return a *= static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator/=(float& a, const BFloat16& b) {
return a /= static_cast<float>(b);
}
/// Arithmetic with doubles
inline C10_HOST_DEVICE double operator+(BFloat16 a, double b) {
return static_cast<double>(a) + b;
}
inline C10_HOST_DEVICE double operator-(BFloat16 a, double b) {
return static_cast<double>(a) - b;
}
inline C10_HOST_DEVICE double operator*(BFloat16 a, double b) {
return static_cast<double>(a) * b;
}
inline C10_HOST_DEVICE double operator/(BFloat16 a, double b) {
return static_cast<double>(a) / b;
}
inline C10_HOST_DEVICE double operator+(double a, BFloat16 b) {
return a + static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator-(double a, BFloat16 b) {
return a - static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator*(double a, BFloat16 b) {
return a * static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator/(double a, BFloat16 b) {
return a / static_cast<double>(b);
}
/// Arithmetic with ints
inline C10_HOST_DEVICE BFloat16 operator+(BFloat16 a, int b) {
return a + static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(BFloat16 a, int b) {
return a - static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator*(BFloat16 a, int b) {
return a * static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(BFloat16 a, int b) {
return a / static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator+(int a, BFloat16 b) {
return static_cast<BFloat16>(a) + b;
}
inline C10_HOST_DEVICE BFloat16 operator-(int a, BFloat16 b) {
return static_cast<BFloat16>(a) - b;
}
inline C10_HOST_DEVICE BFloat16 operator*(int a, BFloat16 b) {
return static_cast<BFloat16>(a) * b;
}
inline C10_HOST_DEVICE BFloat16 operator/(int a, BFloat16 b) {
return static_cast<BFloat16>(a) / b;
}
//// Arithmetic with int64_t
inline C10_HOST_DEVICE BFloat16 operator+(BFloat16 a, int64_t b) {
return a + static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(BFloat16 a, int64_t b) {
return a - static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator*(BFloat16 a, int64_t b) {
return a * static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(BFloat16 a, int64_t b) {
return a / static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator+(int64_t a, BFloat16 b) {
return static_cast<BFloat16>(a) + b;
}
inline C10_HOST_DEVICE BFloat16 operator-(int64_t a, BFloat16 b) {
return static_cast<BFloat16>(a) - b;
}
inline C10_HOST_DEVICE BFloat16 operator*(int64_t a, BFloat16 b) {
return static_cast<BFloat16>(a) * b;
}
inline C10_HOST_DEVICE BFloat16 operator/(int64_t a, BFloat16 b) {
return static_cast<BFloat16>(a) / b;
}
// Overloading < and > operators, because std::max and std::min use them.
inline C10_HOST_DEVICE bool operator>(BFloat16& lhs, BFloat16& rhs) {
return float(lhs) > float(rhs);
}
inline C10_HOST_DEVICE bool operator<(BFloat16& lhs, BFloat16& rhs) {
return float(lhs) < float(rhs);
}
} // namespace c10
namespace std {
template <>
class numeric_limits<c10::BFloat16> {
public:
static constexpr bool is_signed = true;
static constexpr bool is_specialized = true;
static constexpr bool is_integer = false;
static constexpr bool is_exact = false;
static constexpr bool has_infinity = true;
static constexpr bool has_quiet_NaN = true;
static constexpr bool has_signaling_NaN = true;
static constexpr auto has_denorm = numeric_limits<float>::has_denorm;
static constexpr auto has_denorm_loss =
numeric_limits<float>::has_denorm_loss;
static constexpr auto round_style = numeric_limits<float>::round_style;
static constexpr bool is_iec559 = false;
static constexpr bool is_bounded = true;
static constexpr bool is_modulo = false;
static constexpr int digits = 8;
static constexpr int digits10 = 2;
static constexpr int max_digits10 = 4;
static constexpr int radix = 2;
static constexpr int min_exponent = -125;
static constexpr int min_exponent10 = -37;
static constexpr int max_exponent = 128;
static constexpr int max_exponent10 = 38;
static constexpr auto traps = numeric_limits<float>::traps;
static constexpr auto tinyness_before =
numeric_limits<float>::tinyness_before;
static constexpr c10::BFloat16 min() {
return c10::BFloat16(0x0080, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 lowest() {
return c10::BFloat16(0xFF7F, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 max() {
return c10::BFloat16(0x7F7F, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 epsilon() {
return c10::BFloat16(0x3C00, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 round_error() {
return c10::BFloat16(0x3F00, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 infinity() {
return c10::BFloat16(0x7F80, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 quiet_NaN() {
return c10::BFloat16(0x7FC0, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 signaling_NaN() {
return c10::BFloat16(0x7F80, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 denorm_min() {
return c10::BFloat16(0x0001, c10::BFloat16::from_bits());
}
};
} // namespace std
C10_CLANG_DIAGNOSTIC_POP()
#include <torch/headeronly/util/BFloat16.h>

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@ -1,116 +1 @@
#pragma once
// Defines the bloat16 type (brain floating-point). This representation uses
// 1 bit for the sign, 8 bits for the exponent and 7 bits for the mantissa.
#include <c10/macros/Macros.h>
#include <c10/util/bit_cast.h>
#include <cmath>
#include <cstdint>
#include <cstring>
#include <iosfwd>
#include <ostream>
#if defined(__CUDACC__) && !defined(USE_ROCM)
#include <cuda_bf16.h>
#endif
#if defined(CL_SYCL_LANGUAGE_VERSION)
#include <CL/sycl.hpp> // for SYCL 1.2.1
#elif defined(SYCL_LANGUAGE_VERSION)
#include <sycl/sycl.hpp> // for SYCL 2020
#endif
namespace c10 {
namespace detail {
inline C10_HOST_DEVICE float f32_from_bits(uint16_t src) {
float res = 0;
uint32_t tmp = src;
tmp <<= 16;
#if defined(USE_ROCM) && defined(__HIPCC__)
float* tempRes;
// We should be using memcpy in order to respect the strict aliasing rule
// but it fails in the HIP environment.
tempRes = reinterpret_cast<float*>(&tmp);
res = *tempRes;
#else
std::memcpy(&res, &tmp, sizeof(tmp));
#endif
return res;
}
inline C10_HOST_DEVICE uint16_t bits_from_f32(float src) {
uint32_t res = 0;
#if defined(USE_ROCM) && defined(__HIPCC__)
// We should be using memcpy in order to respect the strict aliasing rule
// but it fails in the HIP environment.
uint32_t* tempRes = reinterpret_cast<uint32_t*>(&src);
res = *tempRes;
#else
std::memcpy(&res, &src, sizeof(res));
#endif
return res >> 16;
}
inline C10_HOST_DEVICE uint16_t round_to_nearest_even(float src) {
#if defined(USE_ROCM) && defined(__HIPCC__)
if (src != src) {
#elif defined(_MSC_VER)
if (isnan(src)) {
#else
if (std::isnan(src)) {
#endif
return UINT16_C(0x7FC0);
} else {
const uint32_t U32 = c10::bit_cast<uint32_t>(src);
uint32_t rounding_bias = ((U32 >> 16) & 1) + UINT32_C(0x7FFF);
return static_cast<uint16_t>((U32 + rounding_bias) >> 16);
}
}
} // namespace detail
struct alignas(2) BFloat16 {
uint16_t x;
// HIP wants __host__ __device__ tag, CUDA does not
#if defined(USE_ROCM) && defined(__HIPCC__)
C10_HOST_DEVICE BFloat16() = default;
#else
BFloat16() = default;
#endif
struct from_bits_t {};
static constexpr C10_HOST_DEVICE from_bits_t from_bits() {
return from_bits_t();
}
constexpr C10_HOST_DEVICE BFloat16(unsigned short bits, from_bits_t)
: x(bits) {}
/* implicit */ inline C10_HOST_DEVICE BFloat16(float value);
inline C10_HOST_DEVICE operator float() const;
#if defined(__CUDACC__) && !defined(USE_ROCM)
inline C10_HOST_DEVICE BFloat16(const __nv_bfloat16& value);
explicit inline C10_HOST_DEVICE operator __nv_bfloat16() const;
#endif
#if defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
inline C10_HOST_DEVICE BFloat16(const sycl::ext::oneapi::bfloat16& value);
explicit inline C10_HOST_DEVICE operator sycl::ext::oneapi::bfloat16() const;
#endif
};
inline std::ostream& operator<<(std::ostream& out, const BFloat16& value) {
out << (float)value;
return out;
}
} // namespace c10
#include <c10/util/BFloat16-inl.h> // IWYU pragma: keep
#include <torch/headeronly/util/BFloat16.h>

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@ -1,12 +1,11 @@
#include <gtest/gtest.h>
#include <c10/util/BFloat16-math.h>
#include <c10/util/BFloat16.h>
#include <c10/util/Float8_e4m3fn.h>
#include <c10/util/Float8_e4m3fnuz.h>
#include <c10/util/Float8_e5m2.h>
#include <c10/util/Float8_e5m2fnuz.h>
#include <c10/util/complex.h>
#include <torch/headeronly/util/BFloat16.h>
#include <torch/headeronly/util/Float4_e2m1fn_x2.h>
#include <torch/headeronly/util/Half.h>
@ -18,12 +17,12 @@
#include <torch/headeronly/util/quint8.h>
TEST(TestDtype, TestBFloat16) {
c10::BFloat16 a = 1.0f;
c10::BFloat16 b = 2.0f;
c10::BFloat16 add = 3.0f;
c10::BFloat16 sub = -1.0f;
c10::BFloat16 mul = 2.0f;
c10::BFloat16 div = 0.5f;
torch::headeronly::BFloat16 a = 1.0f;
torch::headeronly::BFloat16 b = 2.0f;
torch::headeronly::BFloat16 add = 3.0f;
torch::headeronly::BFloat16 sub = -1.0f;
torch::headeronly::BFloat16 mul = 2.0f;
torch::headeronly::BFloat16 div = 0.5f;
EXPECT_EQ(a + b, add);
EXPECT_EQ(a - b, sub);

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@ -9,7 +9,7 @@ convert
# c10/util/bit_cast.h, torch/headeronly/util/bit_cast.h
bit_cast
# c10/util/BFloat16-math.h, c10/util/BFloat16.h
# torch/headeronly/util/BFloat16.h
BFloat16
# torch/headeronly/util/Float4_e2m1fn_x2.h

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#pragma once
// Defines the bloat16 type (brain floating-point). This representation uses
// 1 bit for the sign, 8 bits for the exponent and 7 bits for the mantissa.
#include <torch/headeronly/macros/Macros.h>
#include <torch/headeronly/util/bit_cast.h>
#include <cmath>
#include <cstdint>
#include <cstring>
#include <iosfwd>
#include <ostream>
#if defined(__CUDACC__) && !defined(USE_ROCM)
#include <cuda_bf16.h>
#endif
#if defined(CL_SYCL_LANGUAGE_VERSION)
#include <CL/sycl.hpp> // for SYCL 1.2.1
#elif defined(SYCL_LANGUAGE_VERSION)
#include <sycl/sycl.hpp> // for SYCL 2020
#endif
namespace c10 {
struct alignas(2) BFloat16 {
uint16_t x;
// HIP wants __host__ __device__ tag, CUDA does not
#if defined(USE_ROCM) && defined(__HIPCC__)
C10_HOST_DEVICE BFloat16() = default;
#else
BFloat16() = default;
#endif
struct from_bits_t {};
static constexpr C10_HOST_DEVICE from_bits_t from_bits() {
return from_bits_t();
}
constexpr C10_HOST_DEVICE BFloat16(unsigned short bits, from_bits_t)
: x(bits) {}
/* implicit */ inline C10_HOST_DEVICE BFloat16(float value);
inline C10_HOST_DEVICE operator float() const;
#if defined(__CUDACC__) && !defined(USE_ROCM)
inline C10_HOST_DEVICE BFloat16(const __nv_bfloat16& value);
explicit inline C10_HOST_DEVICE operator __nv_bfloat16() const;
#endif
#if defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
inline C10_HOST_DEVICE BFloat16(const sycl::ext::oneapi::bfloat16& value);
explicit inline C10_HOST_DEVICE operator sycl::ext::oneapi::bfloat16() const;
#endif
};
inline std::ostream& operator<<(std::ostream& out, const BFloat16& value) {
out << (float)value;
return out;
}
namespace detail {
inline C10_HOST_DEVICE float f32_from_bits(uint16_t src) {
float res = 0;
uint32_t tmp = src;
tmp <<= 16;
#if defined(USE_ROCM) && defined(__HIPCC__)
float* tempRes;
// We should be using memcpy in order to respect the strict aliasing rule
// but it fails in the HIP environment.
tempRes = reinterpret_cast<float*>(&tmp);
res = *tempRes;
#else
std::memcpy(&res, &tmp, sizeof(tmp));
#endif
return res;
}
inline C10_HOST_DEVICE uint16_t bits_from_f32(float src) {
uint32_t res = 0;
#if defined(USE_ROCM) && defined(__HIPCC__)
// We should be using memcpy in order to respect the strict aliasing rule
// but it fails in the HIP environment.
uint32_t* tempRes = reinterpret_cast<uint32_t*>(&src);
res = *tempRes;
#else
std::memcpy(&res, &src, sizeof(res));
#endif
return res >> 16;
}
inline C10_HOST_DEVICE uint16_t round_to_nearest_even(float src) {
#if defined(USE_ROCM) && defined(__HIPCC__)
if (src != src) {
#elif defined(_MSC_VER)
if (isnan(src)) {
#else
if (std::isnan(src)) {
#endif
return UINT16_C(0x7FC0);
} else {
const uint32_t U32 = c10::bit_cast<uint32_t>(src);
uint32_t rounding_bias = ((U32 >> 16) & 1) + UINT32_C(0x7FFF);
return static_cast<uint16_t>((U32 + rounding_bias) >> 16);
}
}
} // namespace detail
//-------- the following is copied from c10/util/BFloat16-inl.h ---------//
C10_CLANG_DIAGNOSTIC_PUSH()
#if C10_CLANG_HAS_WARNING("-Wimplicit-int-float-conversion")
C10_CLANG_DIAGNOSTIC_IGNORE("-Wimplicit-int-float-conversion")
#endif
/// Constructors
inline C10_HOST_DEVICE BFloat16::BFloat16(float value)
:
#if defined(__CUDACC__) && !defined(USE_ROCM) && defined(__CUDA_ARCH__) && \
__CUDA_ARCH__ >= 800
x(__bfloat16_as_ushort(__float2bfloat16(value)))
#elif defined(__SYCL_DEVICE_ONLY__) && \
defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
x(c10::bit_cast<uint16_t>(sycl::ext::oneapi::bfloat16(value)))
#else
// RNE by default
x(detail::round_to_nearest_even(value))
#endif
{
}
/// Implicit conversions
inline C10_HOST_DEVICE BFloat16::operator float() const {
#if defined(__CUDACC__) && !defined(USE_ROCM)
return __bfloat162float(*reinterpret_cast<const __nv_bfloat16*>(&x));
#elif defined(__SYCL_DEVICE_ONLY__) && \
defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
return float(*reinterpret_cast<const sycl::ext::oneapi::bfloat16*>(&x));
#else
return detail::f32_from_bits(x);
#endif
}
#if defined(__CUDACC__) && !defined(USE_ROCM)
inline C10_HOST_DEVICE BFloat16::BFloat16(const __nv_bfloat16& value) {
x = *reinterpret_cast<const unsigned short*>(&value);
}
inline C10_HOST_DEVICE BFloat16::operator __nv_bfloat16() const {
return *reinterpret_cast<const __nv_bfloat16*>(&x);
}
#endif
#if defined(SYCL_EXT_ONEAPI_BFLOAT16_MATH_FUNCTIONS)
inline C10_HOST_DEVICE BFloat16::BFloat16(
const sycl::ext::oneapi::bfloat16& value) {
x = *reinterpret_cast<const unsigned short*>(&value);
}
inline C10_HOST_DEVICE BFloat16::operator sycl::ext::oneapi::bfloat16() const {
return *reinterpret_cast<const sycl::ext::oneapi::bfloat16*>(&x);
}
#endif
// CUDA intrinsics
#if defined(__CUDACC__) || defined(__HIPCC__)
inline C10_DEVICE BFloat16 __ldg(const BFloat16* ptr) {
#if !defined(USE_ROCM) && defined(__CUDA_ARCH__) && __CUDA_ARCH__ >= 800
return __ldg(reinterpret_cast<const __nv_bfloat16*>(ptr));
#else
return *ptr;
#endif
}
#endif
/// Arithmetic
inline C10_HOST_DEVICE BFloat16
operator+(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) + static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16
operator-(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) - static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16
operator*(const BFloat16& a, const BFloat16& b) {
return static_cast<float>(a) * static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(const BFloat16& a, const BFloat16& b)
__ubsan_ignore_float_divide_by_zero__ {
return static_cast<float>(a) / static_cast<float>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(const BFloat16& a) {
return -static_cast<float>(a);
}
inline C10_HOST_DEVICE BFloat16& operator+=(BFloat16& a, const BFloat16& b) {
a = a + b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator-=(BFloat16& a, const BFloat16& b) {
a = a - b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator*=(BFloat16& a, const BFloat16& b) {
a = a * b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator/=(BFloat16& a, const BFloat16& b) {
a = a / b;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator|(BFloat16& a, const BFloat16& b) {
a.x = a.x | b.x;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator^(BFloat16& a, const BFloat16& b) {
a.x = a.x ^ b.x;
return a;
}
inline C10_HOST_DEVICE BFloat16& operator&(BFloat16& a, const BFloat16& b) {
a.x = a.x & b.x;
return a;
}
/// Arithmetic with floats
inline C10_HOST_DEVICE float operator+(BFloat16 a, float b) {
return static_cast<float>(a) + b;
}
inline C10_HOST_DEVICE float operator-(BFloat16 a, float b) {
return static_cast<float>(a) - b;
}
inline C10_HOST_DEVICE float operator*(BFloat16 a, float b) {
return static_cast<float>(a) * b;
}
inline C10_HOST_DEVICE float operator/(BFloat16 a, float b) {
return static_cast<float>(a) / b;
}
inline C10_HOST_DEVICE float operator+(float a, BFloat16 b) {
return a + static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator-(float a, BFloat16 b) {
return a - static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator*(float a, BFloat16 b) {
return a * static_cast<float>(b);
}
inline C10_HOST_DEVICE float operator/(float a, BFloat16 b) {
return a / static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator+=(float& a, const BFloat16& b) {
return a += static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator-=(float& a, const BFloat16& b) {
return a -= static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator*=(float& a, const BFloat16& b) {
return a *= static_cast<float>(b);
}
inline C10_HOST_DEVICE float& operator/=(float& a, const BFloat16& b) {
return a /= static_cast<float>(b);
}
/// Arithmetic with doubles
inline C10_HOST_DEVICE double operator+(BFloat16 a, double b) {
return static_cast<double>(a) + b;
}
inline C10_HOST_DEVICE double operator-(BFloat16 a, double b) {
return static_cast<double>(a) - b;
}
inline C10_HOST_DEVICE double operator*(BFloat16 a, double b) {
return static_cast<double>(a) * b;
}
inline C10_HOST_DEVICE double operator/(BFloat16 a, double b) {
return static_cast<double>(a) / b;
}
inline C10_HOST_DEVICE double operator+(double a, BFloat16 b) {
return a + static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator-(double a, BFloat16 b) {
return a - static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator*(double a, BFloat16 b) {
return a * static_cast<double>(b);
}
inline C10_HOST_DEVICE double operator/(double a, BFloat16 b) {
return a / static_cast<double>(b);
}
/// Arithmetic with ints
inline C10_HOST_DEVICE BFloat16 operator+(BFloat16 a, int b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a + static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(BFloat16 a, int b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a - static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator*(BFloat16 a, int b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a * static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(BFloat16 a, int b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a / static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator+(int a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) + b;
}
inline C10_HOST_DEVICE BFloat16 operator-(int a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) - b;
}
inline C10_HOST_DEVICE BFloat16 operator*(int a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) * b;
}
inline C10_HOST_DEVICE BFloat16 operator/(int a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) / b;
}
//// Arithmetic with int64_t
inline C10_HOST_DEVICE BFloat16 operator+(BFloat16 a, int64_t b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a + static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator-(BFloat16 a, int64_t b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a - static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator*(BFloat16 a, int64_t b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a * static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator/(BFloat16 a, int64_t b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return a / static_cast<BFloat16>(b);
}
inline C10_HOST_DEVICE BFloat16 operator+(int64_t a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) + b;
}
inline C10_HOST_DEVICE BFloat16 operator-(int64_t a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) - b;
}
inline C10_HOST_DEVICE BFloat16 operator*(int64_t a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) * b;
}
inline C10_HOST_DEVICE BFloat16 operator/(int64_t a, BFloat16 b) {
// NOLINTNEXTLINE(bugprone-narrowing-conversions,cppcoreguidelines-narrowing-conversions)
return static_cast<BFloat16>(a) / b;
}
// Overloading < and > operators, because std::max and std::min use them.
inline C10_HOST_DEVICE bool operator>(BFloat16& lhs, BFloat16& rhs) {
return float(lhs) > float(rhs);
}
inline C10_HOST_DEVICE bool operator<(BFloat16& lhs, BFloat16& rhs) {
return float(lhs) < float(rhs);
}
C10_CLANG_DIAGNOSTIC_POP()
} // namespace c10
namespace torch::headeronly {
namespace detail {
using c10::detail::bits_from_f32;
using c10::detail::f32_from_bits;
using c10::detail::round_to_nearest_even;
} // namespace detail
using c10::BFloat16;
using c10::operator+;
using c10::operator-;
using c10::operator*;
using c10::operator/;
using c10::operator+=;
using c10::operator-=;
using c10::operator*=;
using c10::operator/=;
using c10::operator<;
using c10::operator>;
using c10::operator<<;
} // namespace torch::headeronly
namespace std {
template <>
class numeric_limits<c10::BFloat16> {
public:
static constexpr bool is_signed = true;
static constexpr bool is_specialized = true;
static constexpr bool is_integer = false;
static constexpr bool is_exact = false;
static constexpr bool has_infinity = true;
static constexpr bool has_quiet_NaN = true;
static constexpr bool has_signaling_NaN = true;
static constexpr auto has_denorm = numeric_limits<float>::has_denorm;
static constexpr auto has_denorm_loss =
numeric_limits<float>::has_denorm_loss;
static constexpr auto round_style = numeric_limits<float>::round_style;
static constexpr bool is_iec559 = false;
static constexpr bool is_bounded = true;
static constexpr bool is_modulo = false;
static constexpr int digits = 8;
static constexpr int digits10 = 2;
static constexpr int max_digits10 = 4;
static constexpr int radix = 2;
static constexpr int min_exponent = -125;
static constexpr int min_exponent10 = -37;
static constexpr int max_exponent = 128;
static constexpr int max_exponent10 = 38;
static constexpr auto traps = numeric_limits<float>::traps;
static constexpr auto tinyness_before =
numeric_limits<float>::tinyness_before;
static constexpr c10::BFloat16 min() {
return c10::BFloat16(0x0080, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 lowest() {
return c10::BFloat16(0xFF7F, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 max() {
return c10::BFloat16(0x7F7F, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 epsilon() {
return c10::BFloat16(0x3C00, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 round_error() {
return c10::BFloat16(0x3F00, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 infinity() {
return c10::BFloat16(0x7F80, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 quiet_NaN() {
return c10::BFloat16(0x7FC0, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 signaling_NaN() {
return c10::BFloat16(0x7F80, c10::BFloat16::from_bits());
}
static constexpr c10::BFloat16 denorm_min() {
return c10::BFloat16(0x0001, c10::BFloat16::from_bits());
}
};
} // namespace std