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[libc++][C++03] Fix copy_backward.pass.cpp and equal.pass.cpp (#198812)

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This isn't a back-port of the original PRs fixing this in the normal
headers, since they changed quite a bit more than necessary to fix the
bug.
This commit is contained in:
Nikolas Klauser 2026-05-20 18:40:12 +02:00 committed by GitHub
parent a5cee6c357
commit c5192b75f6
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GPG key ID: B5690EEEBB952194
3 changed files with 27 additions and 27 deletions
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51
libcxx/include/__cxx03/__bit_reference
View file

@ -288,7 +288,7 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_aligned(
difference_type __dn = std::min(static_cast<difference_type>(__last.__ctz_), __n);
__n -= __dn;
unsigned __clz = __bits_per_word - __last.__ctz_;
__storage_type __m = (~__storage_type(0) << (__last.__ctz_ - __dn)) & (~__storage_type(0) >> __clz);
__storage_type __m = (__storage_type(~0) << (__last.__ctz_ - __dn)) & (__storage_type(~0) >> __clz);
__storage_type __b = *__last.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b;
@ -305,7 +305,7 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_aligned(
__n -= __nw * __bits_per_word;
// do last word
if (__n > 0) {
__storage_type __m = ~__storage_type(0) << (__bits_per_word - __n);
__storage_type __m = __storage_type(~0) << (__bits_per_word - __n);
__storage_type __b = *--__last.__seg_ & __m;
*--__result.__seg_ &= ~__m;
*__result.__seg_ |= __b;
@ -330,12 +330,12 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
difference_type __dn = std::min(static_cast<difference_type>(__last.__ctz_), __n);
__n -= __dn;
unsigned __clz_l = __bits_per_word - __last.__ctz_;
__storage_type __m = (~__storage_type(0) << (__last.__ctz_ - __dn)) & (~__storage_type(0) >> __clz_l);
__storage_type __m = (__storage_type(~0) << (__last.__ctz_ - __dn)) & (__storage_type(~0) >> __clz_l);
__storage_type __b = *__last.__seg_ & __m;
unsigned __clz_r = __bits_per_word - __result.__ctz_;
__storage_type __ddn = std::min(__dn, static_cast<difference_type>(__result.__ctz_));
if (__ddn > 0) {
__m = (~__storage_type(0) << (__result.__ctz_ - __ddn)) & (~__storage_type(0) >> __clz_r);
__m = (__storage_type(~0) << (__result.__ctz_ - __ddn)) & (__storage_type(~0) >> __clz_r);
*__result.__seg_ &= ~__m;
if (__result.__ctz_ > __last.__ctz_)
*__result.__seg_ |= __b << (__result.__ctz_ - __last.__ctz_);
@ -348,7 +348,7 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
// __result.__ctz_ == 0
--__result.__seg_;
__result.__ctz_ = static_cast<unsigned>(-__dn & (__bits_per_word - 1));
__m = ~__storage_type(0) << __result.__ctz_;
__m = __storage_type(~0) << __result.__ctz_;
*__result.__seg_ &= ~__m;
__last.__ctz_ -= __dn + __ddn;
*__result.__seg_ |= __b << (__result.__ctz_ - __last.__ctz_);
@ -359,7 +359,7 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
// __result.__ctz_ != 0 || __n == 0
// do middle words
unsigned __clz_r = __bits_per_word - __result.__ctz_;
__storage_type __m = ~__storage_type(0) >> __clz_r;
__storage_type __m = __storage_type(~0) >> __clz_r;
for (; __n >= __bits_per_word; __n -= __bits_per_word) {
__storage_type __b = *--__last.__seg_;
*__result.__seg_ &= ~__m;
@ -369,11 +369,11 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
}
// do last word
if (__n > 0) {
__m = ~__storage_type(0) << (__bits_per_word - __n);
__m = __storage_type(~0) << (__bits_per_word - __n);
__storage_type __b = *--__last.__seg_ & __m;
__clz_r = __bits_per_word - __result.__ctz_;
__storage_type __dn = std::min(__n, static_cast<difference_type>(__result.__ctz_));
__m = (~__storage_type(0) << (__result.__ctz_ - __dn)) & (~__storage_type(0) >> __clz_r);
__m = (__storage_type(~0) << (__result.__ctz_ - __dn)) & (__storage_type(~0) >> __clz_r);
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b >> (__bits_per_word - __result.__ctz_);
__result.__ctz_ = static_cast<unsigned>(((-__dn & (__bits_per_word - 1)) + __result.__ctz_) % __bits_per_word);
@ -382,7 +382,7 @@ _LIBCPP_HIDE_FROM_ABI __bit_iterator<_Cp, false> __copy_backward_unaligned(
// __result.__ctz_ == 0
--__result.__seg_;
__result.__ctz_ = static_cast<unsigned>(-__n & (__bits_per_word - 1));
__m = ~__storage_type(0) << __result.__ctz_;
__m = __storage_type(~0) << __result.__ctz_;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b << (__result.__ctz_ - (__bits_per_word - __n - __dn));
}
@ -650,24 +650,27 @@ _LIBCPP_HIDE_FROM_ABI bool __equal_unaligned(
unsigned __clz_f = __bits_per_word - __first1.__ctz_;
difference_type __dn = std::min(static_cast<difference_type>(__clz_f), __n);
__n -= __dn;
__storage_type __m = (~__storage_type(0) << __first1.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
__storage_type __m = (__storage_type(~0) << __first1.__ctz_) & (__storage_type(~0) >> (__clz_f - __dn));
__storage_type __b = *__first1.__seg_ & __m;
unsigned __clz_r = __bits_per_word - __first2.__ctz_;
__storage_type __ddn = std::min<__storage_type>(__dn, __clz_r);
__m = (~__storage_type(0) << __first2.__ctz_) & (~__storage_type(0) >> (__clz_r - __ddn));
__m = (__storage_type(~0) << __first2.__ctz_) & (__storage_type(~0) >> (__clz_r - __ddn));
if (__first2.__ctz_ > __first1.__ctz_) {
if ((*__first2.__seg_ & __m) != (__b << (__first2.__ctz_ - __first1.__ctz_)))
if (static_cast<__storage_type>(*__first2.__seg_ & __m) !=
static_cast<__storage_type>(__b << (__first2.__ctz_ - __first1.__ctz_)))
return false;
} else {
if ((*__first2.__seg_ & __m) != (__b >> (__first1.__ctz_ - __first2.__ctz_)))
if (static_cast<__storage_type>(*__first2.__seg_ & __m) !=
static_cast<__storage_type>(__b >> (__first1.__ctz_ - __first2.__ctz_)))
return false;
}
__first2.__seg_ += (__ddn + __first2.__ctz_) / __bits_per_word;
__first2.__ctz_ = static_cast<unsigned>((__ddn + __first2.__ctz_) % __bits_per_word);
__dn -= __ddn;
if (__dn > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __dn);
if ((*__first2.__seg_ & __m) != (__b >> (__first1.__ctz_ + __ddn)))
__m = __storage_type(~0) >> (__bits_per_word - __dn);
if (static_cast<__storage_type>(*__first2.__seg_ & __m) !=
static_cast<__storage_type>(__b >> (__first1.__ctz_ + __ddn)))
return false;
__first2.__ctz_ = static_cast<unsigned>(__dn);
}
@ -677,29 +680,29 @@ _LIBCPP_HIDE_FROM_ABI bool __equal_unaligned(
// __first1.__ctz_ == 0;
// do middle words
unsigned __clz_r = __bits_per_word - __first2.__ctz_;
__storage_type __m = ~__storage_type(0) << __first2.__ctz_;
__storage_type __m = __storage_type(~0) << __first2.__ctz_;
for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first1.__seg_) {
__storage_type __b = *__first1.__seg_;
if ((*__first2.__seg_ & __m) != (__b << __first2.__ctz_))
if (static_cast<__storage_type>(*__first2.__seg_ & __m) != static_cast<__storage_type>(__b << __first2.__ctz_))
return false;
++__first2.__seg_;
if ((*__first2.__seg_ & ~__m) != (__b >> __clz_r))
if (static_cast<__storage_type>(*__first2.__seg_ & ~__m) != static_cast<__storage_type>(__b >> __clz_r))
return false;
}
// do last word
if (__n > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __n);
__m = __storage_type(~0) >> (__bits_per_word - __n);
__storage_type __b = *__first1.__seg_ & __m;
__storage_type __dn = std::min(__n, static_cast<difference_type>(__clz_r));
__m = (~__storage_type(0) << __first2.__ctz_) & (~__storage_type(0) >> (__clz_r - __dn));
__m = (__storage_type(~0) << __first2.__ctz_) & (__storage_type(~0) >> (__clz_r - __dn));
if ((*__first2.__seg_ & __m) != (__b << __first2.__ctz_))
return false;
__first2.__seg_ += (__dn + __first2.__ctz_) / __bits_per_word;
__first2.__ctz_ = static_cast<unsigned>((__dn + __first2.__ctz_) % __bits_per_word);
__n -= __dn;
if (__n > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __n);
if ((*__first2.__seg_ & __m) != (__b >> __dn))
__m = __storage_type(~0) >> (__bits_per_word - __n);
if (static_cast<__storage_type>(*__first2.__seg_ & __m) != static_cast<__storage_type>(__b >> __dn))
return false;
}
}
@ -722,7 +725,7 @@ _LIBCPP_HIDE_FROM_ABI bool __equal_aligned(
unsigned __clz = __bits_per_word - __first1.__ctz_;
difference_type __dn = std::min(static_cast<difference_type>(__clz), __n);
__n -= __dn;
__storage_type __m = (~__storage_type(0) << __first1.__ctz_) & (~__storage_type(0) >> (__clz - __dn));
__storage_type __m = (__storage_type(~0) << __first1.__ctz_) & (__storage_type(~0) >> (__clz - __dn));
if ((*__first2.__seg_ & __m) != (*__first1.__seg_ & __m))
return false;
++__first2.__seg_;
@ -738,7 +741,7 @@ _LIBCPP_HIDE_FROM_ABI bool __equal_aligned(
return false;
// do last word
if (__n > 0) {
__storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
__storage_type __m = __storage_type(~0) >> (__bits_per_word - __n);
if ((*__first2.__seg_ & __m) != (*__first1.__seg_ & __m))
return false;
}

2
libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy_backward.pass.cpp
View file

@ -13,8 +13,6 @@
// constexpr OutIter // constexpr after C++17
// copy_backward(InIter first, InIter last, OutIter result);
// XFAIL: FROZEN-CXX03-HEADERS-FIXME
#include <algorithm>
#include <cassert>
#include <cstdint>

1
libcxx/test/std/algorithms/alg.nonmodifying/alg.equal/equal.pass.cpp
View file

@ -26,7 +26,6 @@
// MSVC warning C4244: 'argument': conversion from 'wchar_t' to 'const _Ty', possible loss of data
// MSVC warning C4389: '==': signed/unsigned mismatch
// ADDITIONAL_COMPILE_FLAGS(cl-style-warnings): /wd4242 /wd4244 /wd4389
// XFAIL: FROZEN-CXX03-HEADERS-FIXME
#include <algorithm>
#include <cassert>