[SYCL] Add missing const to several operators of marray class (#2946)

Several unary operators were missing const in arguments.

Signed-off-by: iburylov <[email protected]>

Author: iburyl

sycl/include/CL/sycl/marray.hpp

@@ -276,31 +276,31 @@ template <typename Type, std::size_t NumElements> class marray {
   // && dataT != cl_half
   template <typename T = DataT>
   friend typename std::enable_if<std::is_integral<T>::value, marray>::type
-  operator~(marray &Lhs) {
+  operator~(const marray &Lhs) {
     marray Ret;
     for (size_t I = 0; I < NumElements; ++I) {
       Ret[I] = ~Lhs[I];
     }
     return Ret;
   }
 
-  friend marray<bool, NumElements> operator!(marray &Lhs) {
+  friend marray<bool, NumElements> operator!(const marray &Lhs) {
     marray<bool, NumElements> Ret;
     for (size_t I = 0; I < NumElements; ++I) {
       Ret[I] = !Lhs[I];
     }
     return Ret;
   }
 
-  friend marray operator+(marray &Lhs) {
+  friend marray operator+(const marray &Lhs) {
     marray Ret;
     for (size_t I = 0; I < NumElements; ++I) {
       Ret[I] = +Lhs[I];
     }
     return Ret;
   }
 
-  friend marray operator-(marray &Lhs) {
+  friend marray operator-(const marray &Lhs) {
     marray Ret;
     for (size_t I = 0; I < NumElements; ++I) {
       Ret[I] = -Lhs[I];

sycl/test/basic_tests/marray/marray.cpp

@@ -83,5 +83,15 @@ int main() {
   b___ = t123 < 2;
   assert(b___[0] == true && b___[1] == false && b___[2] == false);
 
+  // test const operator forms
+  t___ = -mint3{1, 2, 3};
+  assert(t___[0] == -1 && t___[1] == -2 && t___[2] == -3);
+  t___ = +mint3{1, 2, 3};
+  assert(t___[0] == +1 && t___[1] == +2 && t___[2] == +3);
+  t___ = ~mint3{1, 2, 3};
+  assert(t___[0] == ~1 && t___[1] == ~2 && t___[2] == ~3);
+  b___ = !mint3{0, 1, 2};
+  assert(b___[0] == true && b___[1] == false && b___[2] == false);
+
   return 0;
 }