[libcxx-commits] [libcxx] Added segmented iterator for std::equal (PR #106254)
via libcxx-commits
libcxx-commits at lists.llvm.org
Tue Aug 27 10:33:57 PDT 2024
https://github.com/NoumanAmir657 updated https://github.com/llvm/llvm-project/pull/106254
>From 69b32e82068d33c2403739710f66751351383750 Mon Sep 17 00:00:00 2001
From: nouman-10x <noumanamir453 at gmail.com>
Date: Tue, 27 Aug 2024 22:27:37 +0500
Subject: [PATCH 1/2] Added segmented iterator for equal
---
libcxx/include/__algorithm/equal.h | 134 +++++++++++++++++++++++++++++
1 file changed, 134 insertions(+)
diff --git a/libcxx/include/__algorithm/equal.h b/libcxx/include/__algorithm/equal.h
index bfc8f72f6eb195..c7d8eb54026bba 100644
--- a/libcxx/include/__algorithm/equal.h
+++ b/libcxx/include/__algorithm/equal.h
@@ -24,6 +24,7 @@
#include <__type_traits/is_equality_comparable.h>
#include <__type_traits/is_volatile.h>
#include <__utility/move.h>
+#include <__iterator/segmented_iterator.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -54,9 +55,68 @@ __equal_iter_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _BinaryPredicate&)
return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
}
+template <class _SegmentedIterator1, class _SegmentedIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+__equal_segment_iter(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _SegmentedIterator2 __first2, _BinaryPredicate __pred) {
+ using _Traits1 = __segmented_iterator_traits<_SegmentedIterator1>;
+ using _Traits2 = __segmented_iterator_traits<_SegmentedIterator2>;
+
+ auto __sfirst1 = _Traits1::__segment(__first1);
+ auto __slast1 = _Traits1::__segment(__last1);
+
+ auto __sfirst2 = _Traits2::__segment(__first2);
+
+ // Both have only 1 segment
+ if (__sfirst1 == __slast1)
+ return std::__equal_iter_impl(
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ __pred);
+
+ { // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
+ if (!std::__equal_iter_impl(
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ __pred)) {
+ return false;
+ }
+ }
+ ++__sfirst1;
+ ++__sfirst2;
+
+ // Iterate over the segments which are guaranteed to be completely in the range
+ while (__sfirst1 != __slast1) {
+ if (!std::__equal_iter_impl(
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ __pred)) {
+ return false;
+ }
+ ++__sfirst1;
+ ++__sfirst2;
+ }
+
+ // Iterate over the last segment
+ if (!std::__equal_iter_impl(
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ __pred)) {
+ return false;
+ }
+
+ return true;
+}
+
template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1, _InputIterator1 __last1, _InputIterator2 __first2, _BinaryPredicate __pred) {
+ if constexpr (__is_segmented_iterator<_InputIterator1>::value && __is_segmented_iterator<_InputIterator2>::value) {
+ return std::__equal_segment_iter(__first1, __last1, __first2, __pred);
+ }
return std::__equal_iter_impl(
std::__unwrap_iter(__first1), std::__unwrap_iter(__last1), std::__unwrap_iter(__first2), __pred);
}
@@ -95,6 +155,75 @@ __equal_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _Up*, _Pred&, _Proj1&,
return std::__constexpr_memcmp_equal(__first1, __first2, __element_count(__last1 - __first1));
}
+template <class _SegmentedIterator1, class _SegmentedIterator2, class _BinaryPredicate, class _Proj1, class _Proj2>
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
+__equal_segment(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _SegmentedIterator2 __first2, _SegmentedIterator2 __last2, _BinaryPredicate __pred, _Proj1& __proj1, _Proj2& __proj2) {
+ using _Traits1 = __segmented_iterator_traits<_SegmentedIterator1>;
+ using _Traits2 = __segmented_iterator_traits<_SegmentedIterator2>;
+
+ auto __sfirst1 = _Traits1::__segment(__first1);
+ auto __slast1 = _Traits1::__segment(__last1);
+
+ auto __sfirst2 = _Traits2::__segment(__first2);
+ auto __slast2 = _Traits2::__segment(__last2);
+
+ // Both have only 1 segment
+ if (__sfirst1 == __slast1 && __sfirst2 == __slast2)
+ return std::__equal_impl(
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ std::__unwrap_iter(_Traits2::__local(__last2)),
+ __pred,
+ __proj1,
+ __proj2);
+
+ { // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
+ if (!std::__equal_impl(
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ std::__unwrap_iter(_Traits2::__end(__sfirst2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
+ }
+ }
+ ++__sfirst1;
+ ++__sfirst2;
+
+ // Iterate over the segments which are guaranteed to be completely in the range
+ while (__sfirst1 != __slast1 && __sfirst2 != __slast2) {
+ if (!std::__equal_impl(
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ std::__unwrap_iter(_Traits2::__end(__sfirst2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
+ }
+ ++__sfirst1;
+ ++__sfirst2;
+ }
+
+ // Iterate over the last segment
+ if (!std::__equal_impl(
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ std::__unwrap_iter(_Traits2::__local(__last2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
+ }
+
+ return __sfirst1 == __slast1 && __sfirst2 == __slast2;
+}
+
template <class _InputIterator1, class _InputIterator2, class _BinaryPredicate>
_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
equal(_InputIterator1 __first1,
@@ -108,6 +237,11 @@ equal(_InputIterator1 __first1,
return false;
}
__identity __proj;
+
+ if constexpr (__is_segmented_iterator<_InputIterator1>::value && __is_segmented_iterator<_InputIterator2>::value) {
+ return std::__equal_segment(__first1, __last1, __first2, __last2, __pred, __proj, __proj);
+ }
+
return std::__equal_impl(
std::__unwrap_iter(__first1),
std::__unwrap_iter(__last1),
>From 04eb22342be699ecc198cf40e4a891eda9dfe319 Mon Sep 17 00:00:00 2001
From: nouman-10x <noumanamir453 at gmail.com>
Date: Tue, 27 Aug 2024 22:33:33 +0500
Subject: [PATCH 2/2] Formatted
---
libcxx/include/__algorithm/equal.h | 122 +++++++++++++++--------------
1 file changed, 64 insertions(+), 58 deletions(-)
diff --git a/libcxx/include/__algorithm/equal.h b/libcxx/include/__algorithm/equal.h
index c7d8eb54026bba..3de7f170953732 100644
--- a/libcxx/include/__algorithm/equal.h
+++ b/libcxx/include/__algorithm/equal.h
@@ -17,6 +17,7 @@
#include <__functional/invoke.h>
#include <__iterator/distance.h>
#include <__iterator/iterator_traits.h>
+#include <__iterator/segmented_iterator.h>
#include <__string/constexpr_c_functions.h>
#include <__type_traits/desugars_to.h>
#include <__type_traits/enable_if.h>
@@ -24,7 +25,6 @@
#include <__type_traits/is_equality_comparable.h>
#include <__type_traits/is_volatile.h>
#include <__utility/move.h>
-#include <__iterator/segmented_iterator.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -56,8 +56,8 @@ __equal_iter_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _BinaryPredicate&)
}
template <class _SegmentedIterator1, class _SegmentedIterator2, class _BinaryPredicate>
-_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
-__equal_segment_iter(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _SegmentedIterator2 __first2, _BinaryPredicate __pred) {
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_segment_iter(
+ _SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _SegmentedIterator2 __first2, _BinaryPredicate __pred) {
using _Traits1 = __segmented_iterator_traits<_SegmentedIterator1>;
using _Traits2 = __segmented_iterator_traits<_SegmentedIterator2>;
@@ -69,18 +69,18 @@ __equal_segment_iter(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1,
// Both have only 1 segment
if (__sfirst1 == __slast1)
return std::__equal_iter_impl(
- std::__unwrap_iter(_Traits1::__local(__first1)),
- std::__unwrap_iter(_Traits1::__local(__last1)),
- std::__unwrap_iter(_Traits2::__local(__first2)),
- __pred);
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ __pred);
{ // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
if (!std::__equal_iter_impl(
- std::__unwrap_iter(_Traits1::__local(__first1)),
- std::__unwrap_iter(_Traits1::__end(__sfirst1)),
- std::__unwrap_iter(_Traits2::__local(__first2)),
- __pred)) {
- return false;
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ __pred)) {
+ return false;
}
}
++__sfirst1;
@@ -89,23 +89,23 @@ __equal_segment_iter(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1,
// Iterate over the segments which are guaranteed to be completely in the range
while (__sfirst1 != __slast1) {
if (!std::__equal_iter_impl(
- std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
- std::__unwrap_iter(_Traits1::__end(__sfirst1)),
- std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
- __pred)) {
- return false;
- }
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ __pred)) {
+ return false;
+ }
++__sfirst1;
++__sfirst2;
}
// Iterate over the last segment
if (!std::__equal_iter_impl(
- std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
- std::__unwrap_iter(_Traits1::__local(__last1)),
- std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
- __pred)) {
- return false;
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ __pred)) {
+ return false;
}
return true;
@@ -156,8 +156,14 @@ __equal_impl(_Tp* __first1, _Tp* __last1, _Up* __first2, _Up*, _Pred&, _Proj1&,
}
template <class _SegmentedIterator1, class _SegmentedIterator2, class _BinaryPredicate, class _Proj1, class _Proj2>
-_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool
-__equal_segment(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _SegmentedIterator2 __first2, _SegmentedIterator2 __last2, _BinaryPredicate __pred, _Proj1& __proj1, _Proj2& __proj2) {
+_LIBCPP_NODISCARD inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 bool __equal_segment(
+ _SegmentedIterator1 __first1,
+ _SegmentedIterator1 __last1,
+ _SegmentedIterator2 __first2,
+ _SegmentedIterator2 __last2,
+ _BinaryPredicate __pred,
+ _Proj1& __proj1,
+ _Proj2& __proj2) {
using _Traits1 = __segmented_iterator_traits<_SegmentedIterator1>;
using _Traits2 = __segmented_iterator_traits<_SegmentedIterator2>;
@@ -170,25 +176,25 @@ __equal_segment(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _Segm
// Both have only 1 segment
if (__sfirst1 == __slast1 && __sfirst2 == __slast2)
return std::__equal_impl(
- std::__unwrap_iter(_Traits1::__local(__first1)),
- std::__unwrap_iter(_Traits1::__local(__last1)),
- std::__unwrap_iter(_Traits2::__local(__first2)),
- std::__unwrap_iter(_Traits2::__local(__last2)),
- __pred,
- __proj1,
- __proj2);
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ std::__unwrap_iter(_Traits2::__local(__last2)),
+ __pred,
+ __proj1,
+ __proj2);
{ // We have more than one segment. Iterate over the first segment, since we might not start at the beginning
if (!std::__equal_impl(
- std::__unwrap_iter(_Traits1::__local(__first1)),
- std::__unwrap_iter(_Traits1::__end(__sfirst1)),
- std::__unwrap_iter(_Traits2::__local(__first2)),
- std::__unwrap_iter(_Traits2::__end(__sfirst2)),
- __pred,
- __proj1,
- __proj2)) {
- return false;
- }
+ std::__unwrap_iter(_Traits1::__local(__first1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__local(__first2)),
+ std::__unwrap_iter(_Traits2::__end(__sfirst2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
+ }
}
++__sfirst1;
++__sfirst2;
@@ -196,29 +202,29 @@ __equal_segment(_SegmentedIterator1 __first1, _SegmentedIterator1 __last1, _Segm
// Iterate over the segments which are guaranteed to be completely in the range
while (__sfirst1 != __slast1 && __sfirst2 != __slast2) {
if (!std::__equal_impl(
- std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
- std::__unwrap_iter(_Traits1::__end(__sfirst1)),
- std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
- std::__unwrap_iter(_Traits2::__end(__sfirst2)),
- __pred,
- __proj1,
- __proj2)) {
- return false;
- }
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__end(__sfirst1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ std::__unwrap_iter(_Traits2::__end(__sfirst2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
+ }
++__sfirst1;
++__sfirst2;
}
// Iterate over the last segment
if (!std::__equal_impl(
- std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
- std::__unwrap_iter(_Traits1::__local(__last1)),
- std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
- std::__unwrap_iter(_Traits2::__local(__last2)),
- __pred,
- __proj1,
- __proj2)) {
- return false;
+ std::__unwrap_iter(_Traits1::__begin(__sfirst1)),
+ std::__unwrap_iter(_Traits1::__local(__last1)),
+ std::__unwrap_iter(_Traits2::__begin(__sfirst2)),
+ std::__unwrap_iter(_Traits2::__local(__last2)),
+ __pred,
+ __proj1,
+ __proj2)) {
+ return false;
}
return __sfirst1 == __slast1 && __sfirst2 == __slast2;
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