Fix performance

README.md

@@ -97,6 +97,7 @@ firefox coverage/index.html &
 | [Gerard Torrent](https://github.com/torrentg/) | Initial work<br/>Code maintainer|
 | [G. Sliepen](https://codereview.stackexchange.com/users/129343/g-sliepen) | [Code review (I)](https://codereview.stackexchange.com/questions/281005/simple-c-circular-queue)<br/>[Code review (II)](https://codereview.stackexchange.com/questions/281152/a-not-so-simple-c20-circular-queue) |
 | [Toby Speight](https://codereview.stackexchange.com/users/75307/toby-speight) | [Code review (II)](https://codereview.stackexchange.com/questions/281152/a-not-so-simple-c20-circular-queue) |
+| [372046933](https://github.com/372046933) | [Fix compile](https://github.com/torrentg/cqueue/pull/3)<br/>[Fix performance issue](https://github.com/torrentg/cqueue/pull/4) |
 
 
 ## License

cqueue.hpp

@@ -3,7 +3,9 @@
 #include <memory>
 #include <limits>
 #include <compare>
+#include <cstddef>
 #include <utility>
+#include <iterator>
 #include <concepts>
 #include <algorithm>
 #include <stdexcept>
@@ -21,7 +23,7 @@ namespace gto {
  * @see https://en.wikipedia.org/wiki/Circular_buffer
  * @see https://github.com/torrentg/cqueue
  * @note This class is not thread-safe.
- * @version 1.0.5
+ * @version 1.0.6
  * @tparam T Items type.
  * @tparam Allocator Allocator.
  */
@@ -321,7 +323,12 @@ constexpr auto gto::cqueue<T, Allocator>::operator=(const cqueue &other) -> cque
  */
 template<std::copyable T, typename Allocator>
 constexpr auto gto::cqueue<T, Allocator>::getUncheckedIndex(size_type pos) const noexcept {
-  return (mFront + pos) & (mReserved - 1);
+  // case power of two (performance improvement x5)
+  if (mReserved > 1 && (mReserved & (mReserved - 1)) == 0) {
+    [[likely]]
+    return ((mFront + pos) & (mReserved - 1));
+  }
+  return ((mFront + pos) % (mReserved == 0 ? 1 : mReserved));
 }
 
 /**