generalize operator+(isl::*, isl::*) to template form

This will ensure that it also applies to templated isl types.

Author: Sven Verdoolaege

tc/external/detail/islpp-inl.h

@@ -55,10 +55,6 @@ inline isl::aff operator+(isl::val v, isl::aff A) {
   return A + v;
 }
 
-inline isl::aff operator+(isl::aff A, isl::aff B) {
-  return A.add(B);
-}
-
 inline isl::aff operator+(isl::aff A, int i) {
   return i + A;
 }

tc/external/detail/islpp.h

@@ -35,6 +35,11 @@ namespace isl {
 // the official ISL C++ bindings.
 //
 
+template <typename T>
+inline T operator+(T a, T b) {
+  return a.add(b);
+}
+
 template <typename T>
 inline T operator-(T a, T b) {
   return a.sub(b);
@@ -57,10 +62,6 @@ inline isl::val operator*(long i, isl::val v) {
   return v * i;
 }
 
-inline isl::val operator+(isl::val l, isl::val r) {
-  return l.add(r);
-}
-
 inline isl::val operator+(isl::val v, long i) {
   return v.add(isl::val(v.get_ctx(), i));
 }
@@ -128,7 +129,6 @@ isl::aff operator*(isl::val V, isl::aff A);
 isl::aff operator/(isl::aff A, int i);
 
 isl::aff operator+(int i, isl::aff A);
-isl::aff operator+(isl::aff A, isl::aff B);
 isl::aff operator+(isl::aff A, int i);
 isl::aff operator+(isl::aff A, isl::val v);
 isl::aff operator+(isl::val v, isl::aff A);