move "function_traits.h" from fluid to phi (#48065)

paddle/phi/kernels/funcs/broadcast_function.h

@@ -176,7 +176,7 @@ __device__ void VectorizedBroadcastKernelImpl(
 #endif
 
   constexpr bool kCallElementwiseAny =
-      paddle::platform::FunctionTraits<Functor>::has_pointer_args;
+      phi::funcs::FunctionTraits<Functor>::has_pointer_args;
   phi::funcs::ElementwisePrimitiveCaller<InT,
                                          ConditionalT<OutT, NumOuts>,
                                          VecSize,
@@ -787,7 +787,7 @@ void BroadcastKernelForDifferentVecSize(
     std::vector<DenseTensor *> *outs,
     int axis,
     Functor func) {
-  using Traits = paddle::platform::FunctionTraits<Functor>;
+  using Traits = phi::funcs::FunctionTraits<Functor>;
   const int kArity =
       Traits::has_pointer_args ? static_cast<int>(ET) : Traits::arity;
   PADDLE_ENFORCE_EQ(

paddle/phi/kernels/funcs/elementwise_base.h

@@ -23,9 +23,9 @@ limitations under the License. */
 #include "paddle/phi/kernels/funcs/math_function.h"
 
 #if defined(__NVCC__) || defined(__HIPCC__) || defined(__xpu__)
-#include "paddle/fluid/platform/function_traits.h"
 #include "paddle/phi/backends/gpu/gpu_launch_config.h"
 #include "paddle/phi/kernels/funcs/aligned_vector.h"
+#include "paddle/phi/kernels/funcs/function_traits.h"
 #include "paddle/phi/kernels/primitive/kernel_primitives.h"
 
 #define HOSTDEVICE __host__ __device__
@@ -563,7 +563,7 @@ int GetVectorizedSizeForTensors(const std::vector<const DenseTensor *> &ins,
 #ifdef PADDLE_WITH_XPU_KP
   int vec_size = 256;
 #else
-  using Traits = paddle::platform::FunctionTraits<Functor>;
+  using Traits = phi::funcs::FunctionTraits<Functor>;
   using ArgsT = typename Traits::ArgsTuple;
   const int Arity = Traits::arity;
   int vec_size = 4;
@@ -736,7 +736,7 @@ __device__ void VectorizedElementwiseKernelImpl(
     int num,
     int read_lens,
     Functor func) {
-  using Traits = paddle::platform::FunctionTraits<Functor>;
+  using Traits = phi::funcs::FunctionTraits<Functor>;
   using ArgsT = typename Traits::ArgsTuple;
   ArgsT args[VecSize];
   ConditionalT<OutT, NumOuts> result[VecSize];
@@ -831,7 +831,7 @@ void ElementwiseKernel(const KPDevice &ctx,
                        const std::vector<const DenseTensor *> &ins,
                        std::vector<DenseTensor *> *outs,
                        Functor func) {
-  using Traits = paddle::platform::FunctionTraits<Functor>;
+  using Traits = phi::funcs::FunctionTraits<Functor>;
   const int kArity = Traits::arity;
   PADDLE_ENFORCE_EQ(ins.size(),
                     kArity,

paddle/fluid/platform/function_traits.h → paddle/phi/kernels/funcs/function_traits.h

-/* Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
+/* Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
 
 Licensed under the Apache License, Version 2.1 (the "License");
 you may not use this file except in compliance with the License.
@@ -16,8 +16,8 @@ limitations under the License. */
 
 #include <tuple>
 
-namespace paddle {
-namespace platform {
+namespace phi {
+namespace funcs {
 template <int Arity, typename... Args>
 struct IsPointerArgs {
   static_assert(Arity == sizeof...(Args), "Arity and Args not match!");
@@ -57,5 +57,5 @@ struct FunctionTraits<ReturnType(Args...)> {
   using ArgsTuple = std::tuple<Args...>;
 };
 
-}  // namespace platform
-}  // namespace paddle
+}  // namespace funcs
+}  // namespace phi