MIR Parser: Report an error when a jump table entry is redefined.

[oota-llvm.git] / include / llvm / ADT / STLExtras.h

diff --git a/include/llvm/ADT/STLExtras.h b/include/llvm/ADT/STLExtras.h
index 0605e522d7e775a11e186fcb22056e9ca0fa1f8b..fd4412c4166fc95367cfb06e3700dfbae266730e 100644 (file)
--- a/include/llvm/ADT/STLExtras.h
+++ b/include/llvm/ADT/STLExtras.h
@@ -196,15 +196,24 @@ inline mapped_iterator<ItTy, FuncTy> map_iterator(const ItTy &I, FuncTy F) {
   return mapped_iterator<ItTy, FuncTy>(I, F);
 }
 
+/// \brief Metafunction to determine if type T has a member called rbegin().
+template <typename T> struct has_rbegin {
+  template <typename U> static char(&f(const U &, decltype(&U::rbegin)))[1];
+  static char(&f(...))[2];
+  const static bool value = sizeof(f(std::declval<T>(), nullptr)) == 1;
+};
+
 // Returns an iterator_range over the given container which iterates in reverse.
 // Note that the container must have rbegin()/rend() methods for this to work.
-template<typename ContainerTy>
-auto reverse(ContainerTy &C)->decltype(make_range(C.rbegin(), C.rend())) {
+template <typename ContainerTy>
+auto reverse(ContainerTy &&C,
+             typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
+                 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
   return make_range(C.rbegin(), C.rend());
 }
 
 // Returns a std::reverse_iterator wrapped around the given iterator.
-template<typename IteratorTy>
+template <typename IteratorTy>
 std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
   return std::reverse_iterator<IteratorTy>(It);
 }
@@ -212,12 +221,14 @@ std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
 // Returns an iterator_range over the given container which iterates in reverse.
 // Note that the container must have begin()/end() methods which return
 // bidirectional iterators for this to work.
-template<typename ContainerTy>
-auto reverse(ContainerTy &&C)
-  ->decltype(make_range(make_reverse_iterator(std::end(C)),
-                        make_reverse_iterator(std::begin(C)))) {
-  return make_range(make_reverse_iterator(std::end(C)),
-                    make_reverse_iterator(std::begin(C)));
+template <typename ContainerTy>
+auto reverse(
+    ContainerTy &&C,
+    typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
+    -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
+                           llvm::make_reverse_iterator(std::begin(C)))) {
+  return make_range(llvm::make_reverse_iterator(std::end(C)),
+                    llvm::make_reverse_iterator(std::begin(C)));
 }
 
 //===----------------------------------------------------------------------===//