xref: /aosp_15_r20/external/pytorch/aten/src/ATen/native/cpu/FillKernel.cpp (revision da0073e96a02ea20f0ac840b70461e3646d07c45)
1 #define TORCH_ASSERT_NO_OPERATORS
2 #include <ATen/Dispatch_v2.h>
3 #include <ATen/Parallel.h>
4 #include <ATen/cpu/vec/vec.h>
5 #include <ATen/cpu/vec/functional.h>
6 #include <ATen/native/TensorIterator.h>
7 #include <ATen/native/cpu/Loops.h>
8 
9 #include <ATen/native/Fill.h>
10 #include <c10/core/Scalar.h>
11 
12 namespace at::native {
13 namespace {
14 
15 
16 template <typename scalar_t>
fill_non_native_type(TensorIterator & iter,const Scalar & value_scalar)17 void fill_non_native_type(TensorIterator& iter, const Scalar& value_scalar) {
18   auto value = value_scalar.to<scalar_t>().x;
19   using H = typename std::make_signed<decltype(value)>::type;  // Signed type has more acceleration
20   // Reserve the representation of value. static_cast<H>(value) is implementation defined.
21   H val = *reinterpret_cast<H*>(std::addressof(value));
22   cpu_kernel_vec</*check_dynamic_cast=*/false>(
23       iter,
24       [val]() -> H { return val; },
25       [val]() { return Vectorized<H>(val); });
26 }
27 
28 template <>
fill_non_native_type(TensorIterator & iter,const Scalar & value_scalar)29 void fill_non_native_type<c10::complex<at::Half>>(TensorIterator& iter, const Scalar& value_scalar) {
30   static_assert(sizeof(c10::complex<at::Half>) == sizeof(int32_t), "Size of ComplexHalf should be 32-bits");
31   auto value = c10::complex<at::Half>(value_scalar.to<c10::complex<float>>());
32   auto val = *reinterpret_cast<int32_t*>(std::addressof(value));
33   cpu_kernel_vec</*check_dynamic_cast=*/false>(
34       iter,
35       [val]() -> int32_t { return val; },
36       [val]() { return Vectorized<int32_t>(val); });
37 }
38 
fill_kernel(TensorIterator & iter,const Scalar & value_scalar)39 void fill_kernel(TensorIterator& iter, const Scalar& value_scalar) {
40   if (iter.dtype() == ScalarType::Half) {
41     fill_non_native_type<at::Half>(iter, value_scalar);
42   } else if (iter.dtype() == ScalarType::BFloat16) {
43     fill_non_native_type<at::BFloat16>(iter, value_scalar);
44   } else if (iter.dtype() == ScalarType::ComplexHalf) {
45     fill_non_native_type<c10::complex<at::Half>>(iter, value_scalar);
46   } else if (iter.dtype() == ScalarType::Float8_e4m3fn) {
47     fill_non_native_type<at::Float8_e4m3fn>(iter, value_scalar);
48   } else if (iter.dtype() == ScalarType::Float8_e5m2) {
49     fill_non_native_type<at::Float8_e5m2>(iter, value_scalar);
50   } else if (iter.dtype() == ScalarType::Float8_e4m3fnuz) {
51     fill_non_native_type<at::Float8_e4m3fnuz>(iter, value_scalar);
52   } else if (iter.dtype() == ScalarType::Float8_e5m2fnuz) {
53     fill_non_native_type<at::Float8_e5m2fnuz>(iter, value_scalar);
54   } else {
55     AT_DISPATCH_V2(
56       iter.dtype(), "fill_cpu", AT_WRAP([&]() {
57         scalar_t value = value_scalar.to<scalar_t>();
58         cpu_kernel_vec(
59             iter,
60             [=]() -> scalar_t { return value; },
61             [=]() { return Vectorized<scalar_t>(value); });
62       }),
63       AT_EXPAND(AT_ALL_TYPES_AND_COMPLEX), kBool, AT_EXPAND(AT_BAREBONES_UNSIGNED_TYPES)
64     );
65   }
66 }
67 
68 } // namespace
69 
70 REGISTER_DISPATCH(fill_stub, &fill_kernel);
71 
72 } // namespace at::native
73