[libcxx] Refactoring SIMD function names in PSTL CPU backend

[AntonRydahl]

This PR addresses a smaller detail discussed in the code review for #66968. Currently, some functions in the libc++ PSTL CPU backend have been appended with a digit to indicate the number of input iterator arguments. However, there is no need to change the name for each version as overloading can be used instead. This PR will make the naming more consistent in the the CPU and the proposed OpenMP backend.

[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Anton Rydahl (AntonRydahl)

Changes

This PR addresses a smaller detail discussed in the code review for #66968. Currently, some functions in the libc++ PSTL CPU backend have been appended with a digit to indicate the number of input iterator arguments. However, there is no need to change the name as overloading can be used instead. This will PR will make the naming more consistent in the the CPU and the proposed OpenMP backend.

---

Full diff: https://github.com/llvm/llvm-project/pull/69029.diff

2 Files Affected:

• (modified) libcxx/include/__algorithm/pstl_backends/cpu_backends/for_each.h (+2-2)
• (modified) libcxx/include/__algorithm/pstl_backends/cpu_backends/transform.h (+4-4)

diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/cpu_backends/for_each.h
index 6cfef932aa48db3..81fd4526b8dbf1d 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backends/for_each.h
@@ -26,7 +26,7 @@
 _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Iterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator __simd_walk_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI _Iterator __simd_walk(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
   _PSTL_PRAGMA_SIMD
   for (_DifferenceType __i = 0; __i < __n; ++__i)
     __f(__first[__i]);
@@ -47,7 +47,7 @@ __pstl_for_each(__cpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
         });
   } else if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
                        __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
-    std::__simd_walk_1(__first, __last - __first, __func);
+    std::__simd_walk(__first, __last - __first, __func);
     return __empty{};
   } else {
     std::for_each(__first, __last, __func);
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/cpu_backends/transform.h
index 2c7647d61a2b0a4..fdf1a2e78dad905 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backends/transform.h
@@ -32,7 +32,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 
 template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
 _LIBCPP_HIDE_FROM_ABI _Iterator2
-__simd_walk_2(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
+__simd_walk(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
   _PSTL_PRAGMA_SIMD
   for (_DifferenceType __i = 0; __i < __n; ++__i)
     __f(__first1[__i], __first2[__i]);
@@ -60,7 +60,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
   } else if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
                        __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
                        __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
-    return std::__simd_walk_2(
+    return std::__simd_walk(
         __first,
         __last - __first,
         __result,
@@ -73,7 +73,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
 }
 
 template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator3 __simd_walk_3(
+_LIBCPP_HIDE_FROM_ABI _Iterator3 __simd_walk(
     _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
   _PSTL_PRAGMA_SIMD
   for (_DifferenceType __i = 0; __i < __n; ++__i)
@@ -116,7 +116,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
                        __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
                        __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
                        __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
-    return std::__simd_walk_3(
+    return std::__simd_walk(
         __first1,
         __last1 - __first1,
         __first2,