【Hackathon 5th No.25】add gammaln api (#60553)

paddle/phi/api/yaml/backward.yaml

@@ -922,6 +922,16 @@
   kernel :
     func : frame_grad
 
+- backward_op : gammaln_grad
+  forward : gammaln(Tensor x) -> Tensor(out)
+  args : (Tensor x, Tensor out_grad)
+  output : Tensor(x_grad)
+  infer_meta :
+    func : UnchangedInferMeta
+    param: [x]
+  kernel :
+    func : gammaln_grad
+
 - backward_op : gather_grad
   forward : gather(Tensor x, Tensor index, Scalar axis=0) -> Tensor(out)
   args : (Tensor x, Tensor index, Tensor out_grad, Scalar axis=0)

paddle/phi/api/yaml/ops.yaml

@@ -1042,6 +1042,16 @@
     data_type : dtype
     backend : place
 
+- op : gammaln
+  args : (Tensor x)
+  output : Tensor(out)
+  infer_meta :
+    func : UnchangedInferMeta
+  kernel :
+    func : gammaln
+  inplace: (x -> out)
+  backward : gammaln_grad
+
 - op : gather
   args : (Tensor x, Tensor index, Scalar axis=0)
   output : Tensor(out)

paddle/phi/kernels/cpu/gammaln_grad_kernel.cc

@@ -0,0 +1,22 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "paddle/phi/kernels/gammaln_grad_kernel.h"
+
+#include "paddle/phi/backends/cpu/cpu_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+#include "paddle/phi/kernels/impl/gammaln_grad_kernel_impl.h"
+
+PD_REGISTER_KERNEL(
+    gammaln_grad, CPU, ALL_LAYOUT, phi::GammalnGradKernel, float, double) {}

paddle/phi/kernels/cpu/gammaln_kernel.cc

@@ -0,0 +1,22 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "paddle/phi/kernels/gammaln_kernel.h"
+
+#include "paddle/phi/backends/cpu/cpu_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+#include "paddle/phi/kernels/impl/gammaln_kernel_impl.h"
+
+PD_REGISTER_KERNEL(
+    gammaln, CPU, ALL_LAYOUT, phi::GammalnKernel, float, double) {}

paddle/phi/kernels/gammaln_grad_kernel.h

@@ -0,0 +1,27 @@
+
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include "paddle/phi/core/dense_tensor.h"
+
+namespace phi {
+
+template <typename T, typename Context>
+void GammalnGradKernel(const Context& dev_ctx,
+                       const DenseTensor& x,
+                       const DenseTensor& d_out,
+                       DenseTensor* d_x);
+}  // namespace phi

paddle/phi/kernels/gammaln_kernel.h

@@ -0,0 +1,26 @@
+
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include "paddle/phi/core/dense_tensor.h"
+
+namespace phi {
+
+template <typename T, typename Context>
+void GammalnKernel(const Context& dev_ctx,
+                   const DenseTensor& x,
+                   DenseTensor* out);
+}  // namespace phi

paddle/phi/kernels/gpu/gammaln_grad_kernel.cu

@@ -0,0 +1,30 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "paddle/phi/kernels/gammaln_grad_kernel.h"
+
+#include "paddle/phi/backends/gpu/gpu_context.h"
+#include "paddle/phi/common/amp_type_traits.h"
+#include "paddle/phi/core/kernel_registry.h"
+
+#include "paddle/phi/kernels/impl/gammaln_grad_kernel_impl.h"
+
+PD_REGISTER_KERNEL(gammaln_grad,
+                   GPU,
+                   ALL_LAYOUT,
+                   phi::GammalnGradKernel,
+                   float,
+                   double,
+                   phi::dtype::float16,
+                   phi::dtype::bfloat16) {}

paddle/phi/kernels/gpu/gammaln_kernel.cu

@@ -0,0 +1,29 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "paddle/phi/kernels/gammaln_kernel.h"
+
+#include "paddle/phi/backends/gpu/gpu_context.h"
+#include "paddle/phi/core/kernel_registry.h"
+
+#include "paddle/phi/kernels/impl/gammaln_kernel_impl.h"
+
+PD_REGISTER_KERNEL(gammaln,
+                   GPU,
+                   ALL_LAYOUT,
+                   phi::GammalnKernel,
+                   float,
+                   double,
+                   phi::dtype::float16,
+                   phi::dtype::bfloat16) {}

paddle/phi/kernels/impl/gammaln_grad_kernel_impl.h

@@ -0,0 +1,92 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include "paddle/phi/common/amp_type_traits.h"
+#include "paddle/phi/kernels/funcs/for_range.h"
+
+namespace phi {
+template <typename T>
+HOSTDEVICE T digamma(T x) {
+  static T c = T{8.5};
+  static T euler_mascheroni = T{0.57721566490153286060};
+  T r;
+  T value;
+  T x2;
+
+  if (x <= T{0.0}) {
+    value = T{0.0};
+    return value;
+  }
+
+  if (x <= T{0.000001}) {
+    value = -euler_mascheroni - T{1.0} / x + T{1.6449340668482264365} * x;
+    return value;
+  }
+
+  value = T{0.0};
+  x2 = x;
+  while (x2 < c) {
+    value = value - T{1.0} / x2;
+    x2 = x2 + T{1.0};
+  }
+
+  r = T{1.0} / x2;
+  value = value + std::log(x2) - T{0.5} * r;
+
+  r = r * r;
+
+  value = value -
+          r * (T{1.0} / T{12.0} -
+               r * (T{1.0} / T{120.0} -
+                    r * (T{1.0} / T{252.0} -
+                         r * (T{1.0} / T{240.0} - r * (T{1.0} / T{132.0})))));
+
+  return value;
+}
+
+template <typename T>
+struct GammalnGradFunctor {
+  GammalnGradFunctor(const T* dout, const T* x, T* output, int64_t numel)
+      : dout_(dout), x_(x), output_(output), numel_(numel) {}
+
+  HOSTDEVICE void operator()(int64_t idx) const {
+    using MT = typename phi::dtype::MPTypeTrait<T>::Type;
+    const MT mp_dout = static_cast<MT>(dout_[idx]);
+    const MT mp_x = static_cast<MT>(x_[idx]);
+    output_[idx] = static_cast<T>(mp_dout * digamma<MT>(mp_x));
+  }
+
+ private:
+  const T* dout_;
+  const T* x_;
+  T* output_;
+  int64_t numel_;
+};
+template <typename T, typename Context>
+void GammalnGradKernel(const Context& dev_ctx,
+                       const DenseTensor& x,
+                       const DenseTensor& d_out,
+                       DenseTensor* d_x) {
+  auto numel = d_out.numel();
+  auto* dout_data = d_out.data<T>();
+  auto* x_data = x.data<T>();
+  auto* dx_data =
+      dev_ctx.template Alloc<T>(d_x, static_cast<size_t>(numel * sizeof(T)));
+  phi::funcs::ForRange<Context> for_range(dev_ctx, numel);
+  GammalnGradFunctor<T> functor(dout_data, x_data, dx_data, numel);
+  for_range(functor);
+}
+}  // namespace phi

paddle/phi/kernels/impl/gammaln_kernel_impl.h

@@ -0,0 +1,49 @@
+// Copyright (c) 2023 PaddlePaddle Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#pragma once
+
+#include "paddle/phi/common/amp_type_traits.h"
+#include "paddle/phi/kernels/funcs/for_range.h"
+
+namespace phi {
+template <typename T>
+struct GammalnFunctor {
+  GammalnFunctor(const T* x, T* output, int64_t numel)
+      : x_(x), output_(output), numel_(numel) {}
+
+  HOSTDEVICE void operator()(int64_t idx) const {
+    using MT = typename phi::dtype::MPTypeTrait<T>::Type;
+    const MT mp_x = static_cast<MT>(x_[idx]);
+    output_[idx] = static_cast<T>(std::lgamma(mp_x));
+  }
+
+ private:
+  const T* x_;
+  T* output_;
+  int64_t numel_;
+};
+
+template <typename T, typename Context>
+void GammalnKernel(const Context& dev_ctx,
+                   const DenseTensor& x,
+                   DenseTensor* out) {
+  auto numel = x.numel();
+  auto* x_data = x.data<T>();
+  auto* out_data = dev_ctx.template Alloc<T>(out);
+  phi::funcs::ForRange<Context> for_range(dev_ctx, numel);
+  GammalnFunctor<T> functor(x_data, out_data, numel);
+  for_range(functor);
+}
+}  // namespace phi

python/paddle/__init__.py

@@ -398,6 +398,8 @@
     frac,
     frac_,
     frexp,
+    gammaln,
+    gammaln_,
     gcd,
     gcd_,
     heaviside,
@@ -775,6 +777,8 @@
     'square_',
     'divide',
     'divide_',
+    'gammaln',
+    'gammaln_',
     'ceil',
     'atan',
     'atan_',

python/paddle/tensor/__init__.py

@@ -278,6 +278,8 @@
     frac,
     frac_,
     frexp,
+    gammaln,
+    gammaln_,
     gcd,
     gcd_,
     heaviside,
@@ -668,6 +670,8 @@
     'real',
     'imag',
     'is_floating_point',
+    'gammaln',
+    'gammaln_',
     'digamma',
     'digamma_',
     'diagonal',