1#pragma once
2
3#include <c10/util/BFloat16.h>
4#include <c10/util/Half.h>
5#include <c10/util/math_compat.h>
6
7namespace c10 {
8
9// Note: Explicit implementation of copysign for Half and BFloat16
10// is needed to workaround g++-7/8 crash on aarch64, but also makes
11// copysign faster for the half-precision types
12template <typename T, typename U>
13inline auto copysign(const T& a, const U& b) {
14 return std::copysign(a, b);
15}
16
17// Implement copysign for half precision floats using bit ops
18// Sign is the most significant bit for both half and bfloat16 types
19inline c10::Half copysign(c10::Half a, c10::Half b) {
20 return c10::Half((a.x & 0x7fff) | (b.x & 0x8000), c10::Half::from_bits());
21}
22
23inline c10::BFloat16 copysign(c10::BFloat16 a, c10::BFloat16 b) {
24 return c10::BFloat16(
25 (a.x & 0x7fff) | (b.x & 0x8000), c10::BFloat16::from_bits());
26}
27
28} // namespace c10
29