21 Commits

Author SHA1 Message Date
Konstantin Varlamov
dc57752031
[libc++][hardening] Categorize assertions that produce incorrect results (#77183)
Introduce a new `argument-within-domain` category that covers cases
where the given arguments make it impossible to produce a correct result
(or create a valid object in case of constructors). While the incorrect
result doesn't create an immediate problem within the library (like e.g.
a null pointer dereference would), it always indicates a logic error in
user code and is highly likely to lead to a bug in the program once the
value is used.
2024-01-20 23:38:02 -08:00
Louis Dionne
9783f28cbb
[libc++] Format the code base (#74334)
This patch runs clang-format on all of libcxx/include and libcxx/src, in
accordance with the RFC discussed at [1]. Follow-up patches will format
the benchmarks, the test suite and remaining parts of the code. I'm
splitting this one into its own patch so the diff is a bit easier to
review.

This patch was generated with:

   find libcxx/include libcxx/src -type f \
      | grep -v 'module.modulemap.in' \
      | grep -v 'CMakeLists.txt' \
      | grep -v 'README.txt' \
      | grep -v 'libcxx.imp' \
      | grep -v '__config_site.in' \
      | xargs clang-format -i

A Git merge driver is available in libcxx/utils/clang-format-merge-driver.sh
to help resolve merge and rebase issues across these formatting changes.

[1]: https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
2023-12-18 14:01:33 -05:00
Louis Dionne
4c19854222
[libc++] Rename _LIBCPP_INLINE_VISIBILITY to _LIBCPP_HIDE_FROM_ABI (#74095)
In preparation for running clang-format on the whole code base, we are
also removing mentions of the legacy _LIBCPP_INLINE_VISIBILITY macro in
favor of the newer _LIBCPP_HIDE_FROM_ABI.

We're still leaving the definition of _LIBCPP_INLINE_VISIBILITY to avoid
creating needless breakage in case some older patches are checked-in
with mentions of the old macro. After we branch for LLVM 18, we can do
another pass to clean up remaining uses of the macro that might have
gotten introduced by mistake (if any) and remove the macro itself at the
same time. This is just a minor convenience to smooth out the transition
as much as possible.

See
https://discourse.llvm.org/t/rfc-clang-formatting-all-of-libc-once-and-for-all
for the clang-format proposal.
2023-12-04 10:25:14 -05:00
Armando Martín
d78ca7324c [libc++] Fix the rotate direction used in countl_zero()
This "bug" was probably not noticed because it doesn't affect any integer
type we currently support. It requires integers with more than 2x the
size of `unsigned long long`. However, with such types, the algorithm
used to break down the large integer into groups of size `unsigned long long`
didn't work because we rotated in the wrong direction.

For example, the 256 bit number (1 << 255) would yield the wrong answer
when used with the algorithm before this patch.

In particular, note that the current rotation happens to work for 128 bit
integers because it just swaps the halves in this case.

Differential Revision: https://reviews.llvm.org/D134625
Co-authored-by: Louis Dionne <ldionne.2@gmail.com>
2023-09-12 18:19:56 -04:00
Zhangyin
a284d0cc9c [libcxx] <experimental/simd> Added aliagned flag types, traits is_simd_flag_type[_v], memory_alignment[_v] and related tests
Reviewed By: #libc, philnik

Differential Revision: https://reviews.llvm.org/D153319
2023-09-12 11:41:44 +08:00
Daniil Kalinin
45500fa08a [libc++] Fix the signature of std::rotl and std::rotr
- Changed parameters type in `std::rotr` and `std::rorl` functions from `unsigned int` to `int`.
- Implemented behaviour for negative parameter values.

Fixes #64544

Reviewed By: #libc, philnik

Spies: arichardson, philnik, libcxx-commits

Differential Revision: https://reviews.llvm.org/D157569
2023-08-12 08:46:11 -07:00
Nikolas Klauser
8670b53e11 [libc++] Optimize ranges::find for vector<bool>
Benchmark results:
```
----------------------------------------------------------------
Benchmark                                    old             new
----------------------------------------------------------------
bm_vector_bool_ranges_find/1             5.64 ns         6.08 ns
bm_vector_bool_ranges_find/2             16.5 ns         6.03 ns
bm_vector_bool_ranges_find/3             20.3 ns         6.07 ns
bm_vector_bool_ranges_find/4             22.2 ns         6.08 ns
bm_vector_bool_ranges_find/5             23.5 ns         6.05 ns
bm_vector_bool_ranges_find/6             24.4 ns         6.10 ns
bm_vector_bool_ranges_find/7             26.7 ns         6.10 ns
bm_vector_bool_ranges_find/8             25.0 ns         6.08 ns
bm_vector_bool_ranges_find/16            27.9 ns         6.07 ns
bm_vector_bool_ranges_find/64            44.5 ns         5.35 ns
bm_vector_bool_ranges_find/512            243 ns         25.7 ns
bm_vector_bool_ranges_find/4096          1858 ns         35.6 ns
bm_vector_bool_ranges_find/32768        15461 ns         93.5 ns
bm_vector_bool_ranges_find/262144      126462 ns          571 ns
bm_vector_bool_ranges_find/1048576     497736 ns         2272 ns
```

Reviewed By: #libc, Mordante

Spies: var-const, Mordante, libcxx-commits

Differential Revision: https://reviews.llvm.org/D156039
2023-08-01 10:28:25 -07:00
varconst
cd0ad4216c [libc++][hardening][NFC] Introduce _LIBCPP_ASSERT_UNCATEGORIZED.
Replace most uses of `_LIBCPP_ASSERT` with
`_LIBCPP_ASSERT_UNCATEGORIZED`.

This is done as a prerequisite to introducing hardened mode to libc++.
The idea is to make enabling assertions an opt-in with (somewhat)
fine-grained controls over which categories of assertions are enabled.
The vast majority of assertions are currently uncategorized; the new
macro will allow turning on `_LIBCPP_ASSERT` (the underlying mechanism
for all kinds of assertions) without enabling all the uncategorized
assertions (in the future; this patch preserves the current behavior).

Differential Revision: https://reviews.llvm.org/D153816
2023-06-28 15:10:31 -07:00
Nikolas Klauser
7d3bba5e2f [libc++] Add [[nodiscard]] extensions to the functions in <bit>
Reviewed By: #libc, ldionne, Mordante

Spies: Mordante, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D152653
2023-06-13 08:01:34 -07:00
Nikolas Klauser
75196f8e72 [libc++] Remove <cstdlib> includes
We changed the `abort` calls when trying to throw exceptions in `-fno-exceptions` mode to `__verbose_abort` calls, which removes the dependency in most files.

Reviewed By: ldionne, #libc

Spies: dim, emaste, mikhail.ramalho, smeenai, libcxx-commits

Differential Revision: https://reviews.llvm.org/D146076
2023-04-09 02:52:33 +02:00
Nikolas Klauser
4f15267d3d [libc++][NFC] Replace _LIBCPP_STD_VER > x with _LIBCPP_STD_VER >= x
This change is almost fully mechanical. The only interesting change is in `generate_feature_test_macro_components.py` to generate `_LIBCPP_STD_VER >=` instead. To avoid churn in the git-blame this commit should be added to the `.git-blame-ignore-revs` once committed.

Reviewed By: ldionne, var-const, #libc

Spies: jloser, libcxx-commits, arichardson, arphaman, wenlei

Differential Revision: https://reviews.llvm.org/D143962
2023-02-15 16:52:25 +01:00
Nikolas Klauser
d05f889535 [libc++] Enable radability-identifier-naming for local variables and fix any problems
Fixes #60658

Reviewed By: Mordante, #libc

Spies: aheejin, sstefan1, libcxx-commits

Differential Revision: https://reviews.llvm.org/D143737
2023-02-11 20:03:53 +01:00
Nikolas Klauser
86aac87fe4 [libc++] Granularize <bit> and remove <__bits>
Reviewed By: Mordante, #libc

Spies: libcxx-commits

Differential Revision: https://reviews.llvm.org/D141225
2023-01-08 17:01:21 +01:00
Nikolas Klauser
e0a66116fc [libc++] Granularize <type_traits> includes in <compare>
Reviewed By: Mordante, #libc

Spies: libcxx-commits

Differential Revision: https://reviews.llvm.org/D140480
2022-12-23 02:58:06 +01:00
Mark de Wever
23b10a4a66 [libc++][NFC] Use concepts in <bit>.
All supported compilers have concepts support so use that in the C++20
functions in <bit>.

s/_LIBCPP_INLINE_VISIBILITY/_LIBCPP_HIDE_FROM_ABI/ as drive-by fix.

Reviewed By: #libc, ldionne

Differential Revision: https://reviews.llvm.org/D127594
2022-06-13 18:17:48 +02:00
Joe Loser
d2baefae68
[libc++] Replace _LIBCPP_HAS_NO_CONCEPTS with _LIBCPP_STD_VER > 17. NFCI.
All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.

Differential Revision: https://reviews.llvm.org/D121528
2022-03-13 12:32:06 -04:00
Louis Dionne
368faacac7 [libc++] Revert "Protect users from relying on detail headers" & related changes
This commit reverts 5aaefa51 (and also partly 7f285f48e77 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.

Differential Revision: https://reviews.llvm.org/D120683
2022-03-01 08:20:24 -05:00
Christopher Di Bella
5aaefa510e [libcxx][modules] protects users from relying on detail headers
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.

Differential Revision: https://reviews.llvm.org/D106124
2022-02-26 09:00:25 +00:00
Arthur O'Dwyer
fa6b9e4010 [libc++] Normalize all our '#pragma GCC system_header', and regression-test.
Now we'll notice if a header forgets to include this magic phrase.

Differential Revision: https://reviews.llvm.org/D118800
2022-02-04 12:27:19 -05:00
Nikolas Klauser
1dc62f2653 [libc++] Implement P1272R4 (std::byteswap)
Implement P1274R4

Reviewed By: Quuxplusone, Mordante, #libc

Spies: jloser, lebedev.ri, mgorny, libcxx-commits, arichardson

Differential Revision: https://reviews.llvm.org/D114074
2021-11-22 01:28:18 +01:00
Louis Dionne
b1fb3d75c9 [libc++] Implement C++20's P0476R2: std::bit_cast
Thanks to Arthur O'Dwyer for fixing up some of the tests.

Differential Revision: https://reviews.llvm.org/D75960
2021-09-09 11:05:54 -04:00