[part 4]change type of function args (#38888)

paddle/fluid/operators/complex_op.h

@@ -25,14 +25,14 @@ namespace operators {
 // functors to use with ElementwiseComputeEx
 template <typename T>
 struct RealAndImagToComplexFunctor {
-  inline HOSTDEVICE platform::complex<T> operator()(const T& x, const T& y) {
+  inline HOSTDEVICE platform::complex<T> operator()(const T x, const T y) {
     return platform::complex<T>(x, y);
   }
 };
 
 template <typename T>
 struct ImagAndRealToComplexFunctor {
-  inline HOSTDEVICE platform::complex<T> operator()(const T& y, const T& x) {
+  inline HOSTDEVICE platform::complex<T> operator()(const T y, const T x) {
     return platform::complex<T>(x, y);
   }
 };

paddle/fluid/operators/label_smooth_op.cu

@@ -28,7 +28,7 @@ struct LabelSmoothFunctor {
     label_dim = static_cast<T>(label_dim_data);
   }
 
-  __device__ __forceinline__ T operator()(const T& x) const {
+  __device__ __forceinline__ T operator()(const T x) const {
     return (static_cast<T>(1 - epsilon) * x +
             static_cast<T>(epsilon / label_dim));
   }
@@ -42,7 +42,7 @@ struct LabelSmoothGradFunctor {
     epsilon = static_cast<T>(epsilon_data);
   }
 
-  __device__ __forceinline__ T operator()(const T& x) const {
+  __device__ __forceinline__ T operator()(const T x) const {
     return static_cast<T>(1 - epsilon) * x;
   }
 };

paddle/fluid/operators/lgamma_op.cu

@@ -21,7 +21,7 @@ namespace operators {
 
 template <typename T>
 struct CudaLgammaFunctor {
-  __device__ __forceinline__ T operator()(const T& x) const {
+  __device__ __forceinline__ T operator()(const T x) const {
     return Eigen::numext::lgamma(x);
   }
 };

paddle/fluid/operators/matrix_rank_op.h

@@ -48,17 +48,17 @@ static DDim RemoveLastDim(const DDim& dim) {
 
 template <typename T>
 struct GreaterThanFunctor {
-  HOSTDEVICE int operator()(const T& a, const T& b) const { return a > b; }
+  HOSTDEVICE int operator()(const T a, const T b) const { return a > b; }
 };
 
 template <typename T>
 struct LessThanFunctor {
-  HOSTDEVICE int operator()(const T& a, const T& b) const { return a < b; }
+  HOSTDEVICE int operator()(const T a, const T b) const { return a < b; }
 };
 
 template <typename T>
 struct GreaterElementFunctor {
-  HOSTDEVICE T operator()(const T& a, const T& b) const {
+  HOSTDEVICE T operator()(const T a, const T b) const {
     if (a > b) {
       return a;
     } else {