Move GeneralDivMod from segmented_array.h to fast_divmod.h (#48934)

* first commit

* add some changes in stack kernel.

* move the location of GeneralDivMod

* fix code format error according to ci

paddle/phi/kernels/funcs/fast_divmod.h

@@ -64,5 +64,32 @@ struct FastDivMod {
   uint32_t multiplier;
 };
 
+template <typename IndexT>
+struct GeneralDivMod {
+ public:
+  explicit GeneralDivMod(IndexT d) { divmoder = phi::funcs::FastDivMod(d); }
+  __device__ inline phi::funcs::FastDivMod::DivModT div_mod(IndexT val) {
+    return divmoder.Divmod(val);
+  }
+
+  phi::funcs::FastDivMod divmoder;
+};
+
+template <>
+struct GeneralDivMod<int64_t> {
+ public:
+  using DivModT = phi::AlignedVector<int64_t, 2>;
+
+  explicit GeneralDivMod(int64_t d) { divisor = d; }
+  __device__ inline DivModT div_mod(int64_t val) {
+    DivModT data;
+    data[0] = val / divisor;
+    data[1] = val - data[0] * divisor;
+    return data;
+  }
+
+  int64_t divisor;
+};
+
 }  // namespace funcs
 }  // namespace phi

paddle/phi/kernels/funcs/segmented_array.h

@@ -19,33 +19,6 @@
 namespace phi {
 namespace funcs {
 
-template <typename IndexT>
-struct GeneralDivMod {
- public:
-  explicit GeneralDivMod(IndexT d) { divmoder = phi::funcs::FastDivMod(d); }
-  __device__ inline phi::funcs::FastDivMod::DivModT div_mod(IndexT val) {
-    return divmoder.Divmod(val);
-  }
-
-  phi::funcs::FastDivMod divmoder;
-};
-
-template <>
-struct GeneralDivMod<int64_t> {
- public:
-  using DivModT = phi::AlignedVector<int64_t, 2>;
-
-  explicit GeneralDivMod(int64_t d) { divisor = d; }
-  __device__ inline DivModT div_mod(int64_t val) {
-    DivModT data;
-    data[0] = val / divisor;
-    data[1] = val - data[0] * divisor;
-    return data;
-  }
-
-  int64_t divisor;
-};
-
 #if !defined(_WIN32)
 #define PADDLE_ALIGN(x) __attribute__((aligned(x)))
 #else
@@ -143,9 +116,8 @@ struct ConstPointerArraySetter : public ArraySetterBase<Context> {
     const T** dev_ptr = nullptr;
     if (Size == SegmentedArraySize::kVariableLength) {
       size_t num_bytes = t.size() * sizeof(T*);
-      dev_ptr =
-          reinterpret_cast<const T**>(ArraySetterBase<Context>::AllocAndCopy(
-              ctx, reinterpret_cast<void*>(ptrs.data()), num_bytes));
+      dev_ptr = reinterpret_cast<const T**>(this->AllocAndCopy(
+          ctx, reinterpret_cast<void*>(ptrs.data()), num_bytes));
     }
 
     array.Set(ptrs, dev_ptr);
@@ -173,7 +145,7 @@ struct PointerArraySetter : public ArraySetterBase<Context> {
     T** dev_ptr = nullptr;
     if (Size == SegmentedArraySize::kVariableLength) {
       size_t num_bytes = t->size() * sizeof(T*);
-      dev_ptr = reinterpret_cast<T**>(ArraySetterBase<Context>::AllocAndCopy(
+      dev_ptr = reinterpret_cast<T**>(this->AllocAndCopy(
           ctx, reinterpret_cast<void*>(ptrs.data()), num_bytes));
     }
 
@@ -199,6 +171,7 @@ inline SegmentedArraySize CalcArraySize(int n) {
     return SegmentedArraySize::kVariableLength;
   }
 }
+
 }  // namespace funcs
 
 #define _SEGMENTED_ARRAY_KERNEL_CASE(size, ...) \