Previously, the segmented iterator optimization for `std::for_each` was restricted to C++23 and later due to its dependency on `__movable_box`, which is not available in earlier standards. This patch eliminates that restriction, enabling consistent optimizations starting from C++11.
By backporting this enhancement, we improve performance across older standards and create opportunities to extend similar optimizations to other algorithms by forwarding their calls to `std::for_each`.
This patch makes the __config_site header modular, which solves various
problems with non-modular headers. This requires going back to
generating the modulemap file, since we only know how to make
__config_site modular when we're not using the per-target runtime dir.
The patch also adds a test that we support
-Wnon-modular-include-in-module, which warns about non-modular includes
from modules.
---------
Co-authored-by: Konstantin Varlamov <varconst@apple.com>
Copies the not-yet-implemented items planned for removal from the
LLVM-20 to the LLVM-21 release notes. This allows to better keep track
of the status of the next release.
This reverts commit d1156fcb56891fb1a426c3e8331a51d47f98a1b8.
This patch fixes the reported incorrect formatting changes and adds
tests for them. The performance should be unaffected, since there are no
significant changes required to fix the bugs.
Specifically, a `>` was changed to a `>=` to also add a `+` in the zero
case, and we're checking for zero now before printing the octal and
hexadecimal prefixes.
Closes#131710
Requirements on character-like types are updated unconditionally,
because `basic_string` does requires the default-constructibility. It
might be possible to make `basic_string_view` support classes with
non-public trivial default constructor, but this doesn't seem sensible.
libcxxabi's `ItaniumDemangle.h` is also updated to avoid deprecated
features.
This macro isn't required if we define all the functions inline. In
fact, quite a few of the marked functions have already been inlined.
This patch basically only moves code around and adds
`_LIBCPP_HIDE_FROM_ABI` to the places where it's been missing so far.
This also removes inlining hints, since it dropps `inline` in some
places, but that shouldn't make much of a difference. The functions tend
to be either really small, so should be inlined anyways, or are big
enough that they shouldn't be inlined even with an inlinehint.
# Overview
As a disclaimer, this is my first PR to LLVM and while I've tried to
ensure I've followed the LLVM and libc++ contributing guidelines,
there's probably a good chance I missed something. If I have, just let
me know and I'll try to correct it as soon as I can.
This PR implements `std::ranges::iota` and
`std::ranges::out_value_result` outlined in
[P2440r1](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2021/p2440r1.html).
As outlined in the paper above, I've:
- Implemented `out_value_result` and added to `<algorithm>`
- Added `out_value_result`, `iota_result`, and two overloads of `iota`
to `std::ranges` in `<numeric>`
- Updated the version macro `__cpp_lib_ranges_iota` in `<version>`
I've also added tests for `ranges::iota` and `ranges::out_value_result`.
Lastly, I added those structs to the appropriate module files.
Partially implements #105184
EDIT: Forgot to mention in the original post, thanks to @hawkinsw for
taking a look at a preliminary version of this PR!
# TODOs
- [x] Updating the range [status
doc](https://github.com/jamesETsmith/llvm-project/blob/main/libcxx/docs/Status/RangesMajorFeatures.csv)
- [x] Ensure all comments from https://reviews.llvm.org/D121436 are
addressed here
- [X] EDIT (I'll do this in a separate PR). ~~I'm open to implementing
the rest of P2440r1 (`ranges::shift_left` and `ranges::shift_right`) if
that's ok, I just wanted to get feedback on `ranges::iota` first~~
- [x] I've been having trouble building the modules locally and want to
make sure that's working properly
Closes: #134060
We should have had a release note in LLVM 20 about implementing P2165R4
since that is technically an ABI and API break for zip_view. We don't
expect anyone to actually hit the ABI issue, but we've come across some
(fairly small) breakage due to the API change, so this should at least
be mentioned in the release notes.
This allows us to remove the need for `_LIBCPP_TEMPLATE_VIS` and fixes a
bunch of missing annotations for RTTI when used across dylib boundaries.
`_LIBCPP_TEMPLATE_VIS` itself will be removed in a separate patch, since
it touches a lot of code.
This patch is a no-op for Clang. Only GCC is affected.
The existing using _ForwardLike declaration already fails with a
subsitution failure. The LWG issue was filed to clarify what should
happen for non-referencable types.
Added test to verify libc++ is already enforcing the new Mandates.
Implements:
- LWG3757 What's the effect of std::forward_like<void>(x)
Closes: #105026
The current implementation already have an __initial_descriptor which
saves the initial state. When release() is called, we will reset the
__initial_descriptor.__cur_ pointer.
This patch also updates the status of LWG3120.
Closes#104274
---------
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
1013fe3c0cfd7582e94ef2d4bfd79da7ea1a1289 used to implement LWG2770, but
cb0d4df97490ec2d2b1cdf7574d26b1bc4063599 made LWG2770 unimplemented
again because of CWG2386.
This patch re-implements LWG2770, while keeping the libc++-specific
implementation strategy (which is controversial as noted in LWG4040).
Drive-by:
- Make the test coverage for the controversial part noted in LWG4040
libc++-only.
- Add the previously missed entry for LWG2770 to the documentation.
https://wg21.link/LWG3088 requires that `forward_list::merge()` is a no-op when passed
`*this`, which aligns with the behavior of `list::merge`. Although libc++'s implementation
of `forward_list::merge()` already meets this requirement, there were no tests to verify
this behavior. This patch adds the necessary tests to ensure that self-merging remains a
no-op and prevents any future regressions on this.
Closes#104942.
This PR optimizes the performance of `std::ranges::rotate` for
`vector<bool>::iterator`. The optimization yields a performance
improvement of up to 2096x.
Closes#64038.
P2513R4 neither touched library wording nor required library
implementation to change. So it was probably a mistake to list it in
libc++'s implementation status table.
Previously, commit 042f07eed8c1acba19ea04310137bee12b18045a claimed that
P0767R1 was implemented in LLVM 7.0, but no deprecation warning was
implemented. This patch adds the missing warnings.
According to the commit history, the constructors removed by LWG4140
have never been added to libc++.
Existence of non-public or deleted default constructor is observable,
this patch tests that there's no such default constructor at all.
This PR optimizes the performance of `std::ranges::swap_ranges` for
`vector<bool>::iterator`, addressing a subtask outlined in issue #64038.
The optimizations yield performance improvements of up to **611x** for
aligned range swap and **78x** for unaligned range swap comparison.
Additionally, comprehensive tests covering up to 4 storage words (256
bytes) with odd and even bit sizes are provided, which validate the
proposed optimizations in this patch.
This relies on Clang's no_specializations attribute which is not
supported by GCC.
Implements:
- LWG2129: User specializations of std::initializer_list
Fixes: #126270
This PR optimizes the performance of `std::ranges::equal` for
`vector<bool>::iterator`, addressing a subtask outlined in issue #64038.
The optimizations yield performance improvements of up to 188x for
aligned equality comparison and 82x for unaligned equality
comparison. Moreover, comprehensive tests covering up to 4 storage words
(256 bytes) with odd and even bit sizes are provided, which validate the
proposed optimizations in this patch.
std::println was originally implemented with support for LWG4088 by
mistake (in 2fd4084fca0c).
The tests already validate the behaviour required by LWG4088.
Fixes: #118348
Completes:
- LWG3359 <chrono> leap second support should allow for negative leap
seconds
- P1361R2 Integration of chrono with text formatting
Implements parts of:
- P0355 Extending <chrono> to Calendars and Time Zones
Fixes: #100432Fixes: #100014
This is technically not necessary in most cases to prevent issues with ADL,
but let's be consistent. This allows us to remove the libcpp-qualify-declval
clang-tidy check, which is now enforced by the robust-against-adl clang-tidy check.
As a follow-up to #121013 (which optimized `ranges::copy`) and #121026
(which optimized `ranges::copy_backward`), this PR enhances the
performance of `std::ranges::{move, move_backward}` for
`vector<bool>::iterator`, addressing a subtask outlined in issue #64038.
The optimizations bring performance improvements analogous to those
achieved for the `{copy, copy_backward}` algorithms: up to 2000x for
aligned moves and 60x for unaligned moves. Moreover, comprehensive
tests covering up to 4 storage words (256 bytes) with odd and even bit
sizes are provided, which validate the proposed optimizations in this
patch.
