[libcxx-commits] [PATCH] D118029: Introduce branchless sorting functions for sort3, sort4 and sort5.

[Marco Gelmi via Phabricator via libcxx-commits]

marcogelmi marked an inline comment as done.
marcogelmi added inline comments.


================
Comment at: libcxx/include/__algorithm/sort.h:187-191
+template <typename _Compare, typename _RandomAccessIterator>
+inline _LIBCPP_HIDE_FROM_ABI
+    __enable_if_t<is_arithmetic<typename iterator_traits<_RandomAccessIterator>::value_type>::value, void>
+    __sort5_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3,
+                             _RandomAccessIterator __x4, _RandomAccessIterator __x5, _Compare __c) {
----------------
Quuxplusone wrote:
> Nit: It's more libc++ style to use `enable_if_t<>* = nullptr` than return type SFINAE; I'd say the advantages are readability and that return type SFINAE greatly increases the length of the mangled name while an extra `void*` type parameter doesn't so much.
> Drive-by `s/typename/class/` and whitespace.
> Likewise below.
> 
I'm not entirely sure why, but this seems to be failing for the c++03 build (it works fine for the others):, e.g. https://reviews.llvm.org/harbormaster/unit/view/2520185/

```
candidate template ignored: substitution failure [with _Compare = std::__debug_less<NonConstArgCmp>, _RandomAccessIterator = int *]: non-type template argument does not refer to any declaration
inline _LIBCPP_HIDE_FROM_ABI void __sort3_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2,
```




Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D118029/new/

https://reviews.llvm.org/D118029