Commit Graph

2989 Commits

Author SHA1 Message Date
Louis Dionne 23776a178f [libc++] Add assertions on OOB accesses in std::array when the debug mode is enabled
Like we do for empty std::array, make sure we have assertions in place
for obvious out-of-bounds issues in std::array when the debug mode is
enabled (which isn't by default).
2020-06-01 16:37:39 -04:00
Louis Dionne 66a14d151e [libc++] NFC: Minor refactoring in std::array 2020-06-01 16:28:44 -04:00
Louis Dionne 7265ff928a [libc++] Fix issues with the triviality of std::array
The Standard is currently unimplementable. We have to pick between:

1. Not implementing constexpr support properly in std::array<T, 0>
2. Making std::array<T, 0> non-trivial even when T is trivial
3. Returning nullptr from std::array<T, 0>::begin()

Libc++ initially picked (1). In 77b9abfc8e, we started implementing constexpr properly, but lost the guarantee of triviality. Since it seems like both (1) and (2) are really important, it seems like (3) is the only viable option for libc++, after all. This is also what other implementations are doing.

This patch moves libc++ from (1) to (3).

It also:
- Improves the test coverage for the various ways of initializing std::array
- Adds tests for the triviality of std::array
- Adds tests for the aggregate-ness of std::array

Reviewed By: #libc, miscco, EricWF, zoecarver

Differential Revision: https://reviews.llvm.org/D80821
2020-05-29 16:32:55 -07:00
Louis Dionne d0fcdcd28f [libc++] Fix the LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT setting
When the __config_site header is generated, but LIBCXX_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
wasn't specified, _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT would be defined
to 0, which was the NonUnique RTTI comparison implementation. The intent
was to use the Unique RTTI comparison implementation in that case, which
caused https://llvm.org/PR45549.

Instead, use a proper "switch" to select the RTTI comparison implementation.
Note that 0 can't be used as a value, because that is treated the same
by CMake as a variable that is just not defined.

Differential Revision: https://reviews.llvm.org/D80037
2020-05-29 06:14:30 -04:00
Louis Dionne ebddf90a4e [libc++] NFC: Remove outdated numbering in <bit> synopsis 2020-05-28 14:31:21 -04:00
Louis Dionne 77b9abfc8e [libc++] Complete overhaul of constexpr support in std::array
This commit adds missing support for constexpr in std::array under all
standard modes up to and including C++20. It also transforms the <array>
tests to check for constexpr-friendliness under the right standard modes.

Fixes https://llvm.org/PR40124
Fixes rdar://57522096
Supersedes https://reviews.llvm.org/D60666

Differential Revision: https://reviews.llvm.org/D80452
2020-05-28 12:31:06 -04:00
Marek Kurdej d1dbda10ce [libc++] [LWG3201] Update status page: lerp should be marked noexcept.
Summary: Update status page and test synopsis. Add synopsis in <cmath>.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D80456
2020-05-25 22:28:21 +02:00
zoecarver 6e48a6e407 [libcxx] Fix deprecation warning by suppressing deprecated around
__test_has_construct.

In C++17 some tests started failing after a521532aa1. This fixes those errors by suppressing the deprecation warning when calling `construct` in `__test_has_construct`. This is the same solution as `__has_destroy_test` already uses.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80481
2020-05-23 14:33:10 -07:00
zoecarver a521532aa1 [NFC] Remove non-variadic overloads of allocator_traits::construct.
Summary:
Libcxx only supports compilers with variadics. We can safely remove all "fake" variadic overloads of allocator_traits::construct.

This also provides the correct behavior if anything other than exactly one argument is supplied to allocator_traits::construct in C++03 mode.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80067
2020-05-23 14:03:47 -07:00
Marek Kurdej 174322c273 [libc++] Mark __cpp_lib_hardware_interference_size as unimplemented. This fxes bug PR41423.
Summary:
As described in the bug report:
The commit a8b9f59e8caf378d56e8bfcecdb22184cdabf42d "Implement feature test macros using a script" added test features macros for libc++. Among others, it added `__cpp_lib_hardware_interference_size`. However, there is nothing like std::hardware_constructive_interference_size nor std::hardware_destructive_interference_size, that should be in header <new>.

* https://bugs.llvm.org/show_bug.cgi?id=41423

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D80431
2020-05-23 14:33:50 +02:00
Louis Dionne 485b9083fe [libc++] Mark __u64toa and __u32toa as noexcept
The two functions don't throw, and the generated code is better when
we explicitly tell the compiler that the functions are noexcept. This
isn't an ABI break because the signatures of the functions stay the
same with or without noexcept.

Fixes https://llvm.org/PR46016

Differential Revision: https://reviews.llvm.org/D80379
2020-05-22 16:11:44 -04:00
Louis Dionne 0161874c04 [libc++] NFC: Inline array<T,N>::at methods inside the class
All other methods are defined in the class, so this increases consistency.
2020-05-22 09:24:07 -04:00
Marek Kurdej 0c148430cf Reland [libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion.
Summary:
This LWG issue states that the result of `year_month_day_last::day()` is implementation defined if `ok()` is `false`.
However, from user perspective, calling `day()` in this situation will lead to a (possibly difficult to find) crash.
Hence, I have added an assertion to warn user at least when assertions are enabled.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D70346
2020-05-21 21:55:38 +02:00
David Nicuesa 3411a1a920 Fix compile for -DLIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY
Summary: Compilation with  -DLIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY was failing due to missing declarations of functions used in libcxx/include/atomic. The lines this commit affects are the places where those functions are defined, now moved to be always defined.

Reviewers: #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: miyuki, dexonsmith, ldionne, jfb, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80372
2020-05-21 13:48:59 +01:00
Jan Wilken Dörrie 416b1560c5 [libcxx] Remove swap for std::span
This change removes both the member function swap and the free function
overload of swap for std::span. While swap is a member and overloaded
for every other container in the standard library [1], it is neither a
member function nor a free function overload for std::span [2].
Thus the corresponding implementation should be removed.

[1] https://eel.is/c++draft/libraryindex#:swap
[2] https://eel.is/c++draft/span.overview

Differential Revision: https://reviews.llvm.org/D69827
2020-05-20 14:34:21 -04:00
zoecarver ca5bff18fc [NFC] Remove non-rvlaue non-variadic allocator::construct overloads.
Summary: All supported compilers have rvalues and variadics so we can safely remove the overloads of allocator::construct which are only enabled on compilers without rvalues and variadics.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80068
2020-05-19 17:25:00 -07:00
zoecarver b8998ab9c2 [NFC] Remove non-rvlaue non-variadic allocator::construct overloads.
Summary: All supported compilers have rvalues and variadics so we can safely remove the overloads of allocator::construct which are only enabled on compilers without rvalues and variadics.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80068
2020-05-19 17:21:35 -07:00
zoecarver 21d4050e2c Mark shared_ptr::__create_with_control_block as noexcept.
Summary: The default constructor for shared_ptr and shared_ptr::__enable_weak_this are both noexcept so, shared_ptr::__create_with_control_block can also be marked noexcept.

Reviewers: ldionne, #libc!

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D80070
2020-05-19 17:17:16 -07:00
zoecarver c98648a175 [NFC] Add _EnableIfLValueCallable and move reference out of __callable.
Summary: In std::functional moves the reference out of the `__callable` implementation and replaces `_EnableIfCallable` with `_EnableIfLValueCallable` (`_EnableIfLValueCallable` passes `__callable` an lvalue reference type).

    Reviewers: ldionne, #libc!

    Subscribers: dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D80071
2020-05-19 17:15:28 -07:00
Michael Schellenberger Costa c579ab9962 [libcxx][type_traits] Add C++20 changes to common_type
Summary: This already implements the expected changes for LWG-3205

Reviewers: mclow.lists, EricWF, CaseyCarter, cjdb, #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: dexonsmith, broadwaylamb, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74350
2020-05-18 14:06:32 +02:00
Michael Schellenberger Costa ab9f11168f [libcxx][span] Implement solution to LWG-3255
This implements the relaxed requirements on the std::array constructors of span,
where the type only needs to be convertible to the element type of the span.

Note that the previous tests were not sufficient, as the const array<T, n> constructor
was only tested for compile time and the array<T, N> only during runtime.

Restructure the tests so that we can test conversions as well as both constructors.

Differential Revision: https://reviews.llvm.org/D75706
2020-05-14 10:50:44 -04:00
Michael Schellenberger Costa 79941086fb [libc++][span] SFINAE span default constructor on Extent == 0
The default constructor of a static span requires _Extent == 0 so
SFINAE it out rather than using a static_assert

Differential Revision: https://reviews.llvm.org/D71994
2020-05-14 09:35:07 -04:00
Michael Schellenberger Costa c5ff4031c6 [libcxx][span] Remove const_iterator from std::span
This implements the resolution to LWG-3320.

Differential Revision: https://reviews.llvm.org/D75642
2020-05-14 08:34:32 -04:00
Michael Schellenberger Costa c73a491d10 [libcxx][span] Remove tuple interface
This implements P2116 by removing the tuple interface from std::span.

Differential Revision: https://reviews.llvm.org/D75640
2020-05-14 08:25:49 -04:00
Michael Schellenberger Costa 6d2599e4f7 [libcxx][span] Implement P1976R2
This resolves the NB comment about the construction of a fixed-size span
from a dynamic range.

Differential Revision: https://reviews.llvm.org/D74577
2020-05-13 09:52:47 -04:00
Marek Kurdej ab61fe4150 Revert "[libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion."
This reverts commit e25a2601aa.
It was failing due to _LIBCPP_ASSERT throwing in a method marked noexcept.
2020-05-13 13:16:43 +02:00
Marek Kurdej e25a2601aa [libc++] [LWG3321] Mark "year_month_day_last::day() specification does not cover !ok() values" issue as "Nothing to do", but add assertion.
Summary:
This LWG issue states that the result of `year_month_day_last::day()` is implementation defined if `ok()` is `false`.
However, from user perspective, calling `day()` in this situation will lead to a (possibly difficult to find) crash.
Hence, I have added an assertion to warn user at least when assertions are enabled.
I am however not aware of the libc++ stand on the desired behaviour.

Reviewers: ldionne, mclow.lists, EricWF, #libc

Reviewed By: ldionne, #libc

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70346
2020-05-13 11:45:55 +02:00
zoecarver 8aa2266fd8 [libcxx] Constrain function assignment operator (2574).
This patch fixes LWG issue 2574.

Differential Review: https://reviews.llvm.org/D62928
2020-05-12 18:57:50 -07:00
zoecarver ce195fb22b [libcxx] Re-commit: shared_ptr changes from library fundamentals (P0414R2).
Implements P0414R2:
  * Adds support for array types in std::shared_ptr.
  * Adds reinterpret_pointer_cast for shared_ptr.

Re-committing now that the leaking tests are fixed.

Differential Revision: https://reviews.llvm.org/D62259
2020-05-12 11:23:18 -07:00
zoecarver 5eb55483eb Revert "[libcxx] shared_ptr changes from library fundamentals (P0414R2)."
This reverts commit e8c13c182a.
2020-05-11 22:43:17 -07:00
zoecarver e8c13c182a [libcxx] shared_ptr changes from library fundamentals (P0414R2).
Implements P0414R2:
  * Adds support for array types in std::shared_ptr.
  * Adds reinterpret_pointer_cast for shared_ptr.

Differential Revision: https://reviews.llvm.org/D62259
2020-05-11 18:46:29 -07:00
Eric Fiselier c490c5e81a Reland [libc++] Move abs and div into stdlib.h to fix header cycle.
This commit should will break libc++ without local submodule visibility, but
the LLVM+modules bots are now all using this mode. Before the Green Dragon
LLDB bot was failing to compile with a libc++ built with this commit as LSV
was disabled on macOS.

Original summary:

libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-05-08 21:52:27 +02:00
zoecarver 26466efe08 Revert "[libc++] ECMAScript IdentityEscape is ambiguous (2584)"
This reverts commit 6d2a66b10d.

The regex expressions in some lld tests need to be fixed. Reverting
until those are fixed.
2020-05-08 10:37:04 -07:00
zoecarver 6d2a66b10d [libc++] ECMAScript IdentityEscape is ambiguous (2584)
This patch fixes [[ https://cplusplus.github.io/LWG/issue2584 | 2584 ]]. Now the following works:
    const std::regex r1("\\z");
    assert(std::regex_match("z", r1));

Differential Revision: https://reviews.llvm.org/D66610
2020-05-07 14:26:25 -07:00
Marcel Hlopko c9e6519d15 Remove unused _LIBCPP_RAW_ITERATORS
Summary: This change removes seemingly unused _LIBCPP_RAW_ITERATORS.

Reviewers: #libc, EricWF, ldionne

Reviewed By: #libc, EricWF, ldionne

Subscribers: dexonsmith, ldionne, gribozavr2, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D79323
2020-05-07 22:26:15 +02:00
Antonio Sanchez aa0b991dcf [libc++] Fix ostream for complex numbers with fixed field width
The ostream operator<< is currently broken for std::complex with
specified field widths.

This patch a partial revert of c3478eff7a (reviewed as D71214),
restoring the correct behavior.

Differential Revision: https://reviews.llvm.org/D78816
2020-05-07 13:51:07 -04:00
Louis Dionne 31d41e3879 [libc++] Add tests for _LIBCPP_HAS_MERGED_TYPEINFO_NAMES_DEFAULT
The issue on Apple platforms was fixed in 2464d8135e, but this commit
adds some tests to make sure we don't regress.

See https://llvm.org/PR45549.

Differential Revision: https://reviews.llvm.org/D78963
2020-05-07 12:40:02 -04:00
Logan Smith 83564056d4 [libcxx] Add deduction guides for shared_ptr and weak_ptr
This patch adds deduction guides to <memory> to allow deducing
construction of shared_ptrs from unique_ptrs, and from weak_ptrs
and vice versa, as specified by C++17.

Differential Revision: https://reviews.llvm.org/D69603
2020-05-07 12:07:48 -04:00
Logan Smith 5b4a98eb58 [libcxx] Qualify make_pair in searcher implementations to prevent ADL
This patch adds `_VSTD::` to some calls to `make_pair` inside the
implementations of searchers, to prevent things exploding if there is
a make_pair in an associated namespace of a user-defined type.
https://godbolt.org/z/xAFG98

Differential Revision: https://reviews.llvm.org/D72640
2020-05-07 11:57:10 -04:00
Marek Kurdej 3e895085de [libc++][P1115][C++20] Improving the Return Value of Erase-Like Algorithms II: Free erase/erase if.
Summary:
This patch adds return type to std::erase and std::erase_if functions.

Also:
* Update __cpp_lib_erase_if to 202002L.
* Fix synopsis in unordered_map.
* Fix generate_feature_test_macro_components.py script.

Reviewers: EricWF, mclow.lists, ldionne, #libc

Reviewed By: ldionne, #libc

Subscribers: broadwaylamb, zoecarver, dexonsmith, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75905
2020-05-02 14:04:50 +02:00
Diogo Sampaio c14ac8043e [FIX][libc++][Regex] Using regex_constants match_prev_avail | match_not_bol | match_not_bow
Summary:
pr42199
When using regex_constants::match_prev_avail, it is defined that
--first is valid, and match_not_bol and match_not_bow should be
ignored. At the moment these flags are not ignored. This fixis that.

Reviewers: ldionne, miyuki, EricWF, mclow.lists, #libc

Reviewed By: ldionne, miyuki, #libc

Subscribers: broadwaylamb, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75622
2020-04-30 23:36:25 +01:00
Saleem Abdulrasool 88af3ddb1e build: update libc++ as there are some bots with integrated build
Some of the builders are building with C++ in the unified build.  Merge
this without review to try to restore the builder.
2020-04-28 20:07:28 +00:00
Raphael Isemann bd2965c9db Revert "Recommit [libc++] Move abs and div into stdlib.h to fix header cycle."
It seems that D74892 still hasn't fixed the issue on the bot. Currently
investigating the bot breakage and meanwhile (again) reverting this...
2020-04-28 20:23:22 +02:00
Eric Fiselier d0846b432c Recommit [libc++] Move abs and div into stdlib.h to fix header cycle.
This relands this commit as it broke the LLDB bot the first time it landed.
See also the discussion on https://reviews.llvm.org/rG82b47b2978405f802a33b00d046e6f18ef6a47be

Since D74892 this code should now also work on macOS.

Original description:

libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-04-28 15:42:36 +02:00
Louis Dionne f76c42416c [libc++] Improve the detection of whether the blocks runtime is available
The runtime for Blocks may not be available even though the Blocks
language extension _is_ available. Instead of potentially failing,
this commit is much more conservative and assumes the runtime for
Blocks is only provided on Apple platforms.

Differential Revision: https://reviews.llvm.org/D78757
2020-04-24 07:02:21 -04:00
Louis Dionne cd66970b37 [libc++] Don't try to include <Block.h> when not available 2020-04-22 15:22:12 -04:00
Louis Dionne 430b00954c [libc++] Add support for blocks in std::function
rdar://14390808
2020-04-22 14:58:02 -04:00
Dan Albert 75c4408653 Reland: Don't expose unavailable cstdio functions.
Marked unsupported for C++03 and C++11 since this test uses alias
declarations, and at least one C++03 bot was failing with
-Wc++11-extensions.

Change-Id: I8c3a579edd7eb83e0bc74e85d116b68f22400161
2020-04-16 12:51:08 -07:00
Louis Dionne 548d501082 [libc++] NFC: Reindent impossible to read conditional in __config 2020-04-16 15:02:03 -04:00
Louis Dionne 8079f8a7e8 [libc++] Simplify conditional in __config for _LIBCPP_NO_RTTI
We don't support GCC's older than 5.x anymore.
2020-04-16 12:51:30 -04:00
Martijn Vels 7ba045a430 Make basic_string::operator=() tail call properly
Summary: We discovered that the compiler may chose not to inline the operator=, which leads to an expensive extra stack frame. This change makes __assign_no_alias always tail called.

Reviewers: EricWF, #libc!

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D77913
2020-04-10 19:41:46 -04:00
Eric Fiselier c6eb584c64 [libc++] Fix recursive instantiation in std::array.
The use of the `&& ...` fold expression in std::array's deduction guides
recursively builds a set of binary operator expressions of depth N where
`N` is the number of elements in the initializer.

This is problematic because arrays may be large, and instantiation
depth is limited.

This patch addresses the issue by flattening the SFINAE using
the existing `__all` type trait.
2020-04-09 17:42:10 -04:00
Eric Fiselier 601f763182 [libcxx] Adds [concept.same]
Patch from Christopher Di Bella (cjdb@google.com)
Reviewed as https://reviews.llvm.org/D74291

Adds `std::same_as` to libc++. Since there aren't clang-format rules for
//requires-expressions//, I'll need to disable the formatter in certain areas.
2020-04-08 18:00:13 -04:00
zoecarver b25ec45809 Fix __is_pointer builtin type trait to work with Objective-C pointer types.
Summary: 5ade17e broke __is_pointer for Objective-C pointer types. This patch fixes the builtin and re-applies the change to type_traits.

Tags: #clang, #libc

Differential Revision: https://reviews.llvm.org/D77519
2020-04-08 10:02:53 -07:00
Dan Albert 50280c1895 Revert "Don't expose unavailable cstdio functions."
Broke builders that emit different diagnostics. e.g.:

error: 'warning' diagnostics seen but not expected:
  Line 13: alias declarations are a C++11 extension
  Line 20: alias declarations are a C++11 extension

This reverts commit ff87813715.
2020-04-07 15:36:44 -07:00
Dan Albert ff87813715 Don't expose unavailable cstdio functions.
Summary: These aren't available on Android in all configurations.

Reviewers: EricWF, mclow.lists, #libc, ldionne

Reviewed By: EricWF, #libc, ldionne

Subscribers: broadwaylamb, dexonsmith, ldionne, krytarowski, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76093
2020-04-07 15:02:30 -07:00
Louis Dionne 46c3876188 [libc++] Add availability markup for the C++20 Synchronization Library on Apple 2020-04-06 18:07:26 -04:00
Dan Albert cbf1904a3e Upstream Bionic definitions of ctype_base/regex.
Summary:
This is a patch that Android has been carrying in its tree for several
years. This patch upstreams the existing ABI.

There's some historical cruft here. __regex_word used to be a part of
regex_traits rather than ctype_base. Bionic also used to use its own
ctype implementation because the libc++ builtin one wasn't available
yet. Bionic's ctype masks were 8 bits wide and already saturated, so a
wider type needed to be used for the regex mask, and the existing
value was already used so Android needed to specify its own.

Since then Android has migrated to the builtin ctype implementation
and this patch probably should have been dropped then. Unfortunately
that was not noticed at the time, so now we need to keep this to
maintain the current ABI.

Reviewers: EricWF, #libc, ldionne

Reviewed By: #libc, ldionne

Subscribers: dexonsmith, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76171
2020-04-06 13:38:16 -07:00
Joerg Sonnenberger 98f77828a9 Avoid using std::max_align_t in pre-C++11 mode
Always depend on the compiler to have a correct implementation of
max_align_t in stddef.h and don't provide a fallback. For pre-C++11,
require __STDCPP_NEW_ALIGNMENT__ in <new> as provided by clang in all
standard modes. Adjust test cases to avoid testing or using max_align_t
in pre-C++11 mode and also to better deal with alignof(max_align_t)>16.
Document requirements of the alignment tests around natural alignment of
power-of-two-sized types.

Differential revision: https://reviews.llvm.org/D73245
2020-04-04 01:38:41 +02:00
Louis Dionne 3d94f3060c [libc++] Fix is_pointer support for Objective-C++
This test regressed with 5ade17e0ca, but we never noticed it because
.pass.mm tests were skipped due to a bug in our Lit config. This commit
fixes is_pointer (by essentially reverting tha part of 5ade17e0ca) and
also adds .pass.mm tests to the list of supported test suffixes.

We can explore how to support __is_pointer with Objective-C++ qualifiers
as a follow-up -- the main goal of this commit is to fix the regression
quickly and make sure all tests of the suite are run.
2020-04-03 11:09:59 -04:00
zoecarver e6a39f00e8 [libcxx] Stop using builtin type traits for is_floating_point and is_arithmetic.
Based on an issue brought up in https://reviews.llvm.org/D67900, this commit reverts the changes to is_floating_point and  is_arithmetic made in D67900.

After D67900 landed, __float128 behaved differently in those two type traits, causing compiler errors in numeric limits (and possibly others).
2020-04-01 16:57:08 -07:00
Louis Dionne e9271a494f Remove legacy CMake targets for libcxx and libcxxabi
We've been meaning to remove those targets for a while, and the fix is
simple enough cause they're all just aliases to other targets.

This is a re-application of f383fb40b1, wich was reverted in 04d48111b
because the build bots had not been updated yet. The build bot configurations
have now been updated not to use the deprecated targets, and I verified
that they were using the non-deprecated targets, so we should be good
unless I missed a bot.

Differential Revision: https://reviews.llvm.org/D76104
2020-03-30 09:45:21 -04:00
Louis Dionne 04d48111bf Revert "Remove legacy CMake targets for libcxx and libcxxabi"
This reverts commit f383fb40b. It looks like several of our build bots
are still using the legacy target names, so we'll change those before
we commit this change again.
2020-03-23 11:03:00 -04:00
Louis Dionne f383fb40b1 Remove legacy CMake targets for libcxx and libcxxabi
We've been meaning to remove those targets for a while, and the fix is
simple enough cause they're all just aliases to other targets.

There's no doubt this commit will break some CI systems, however the
fix is trivial.

Differential Revision: https://reviews.llvm.org/D76104
2020-03-23 10:51:23 -04:00
zoecarver 9e2207a00b [libc++] fix non-builtin is_void implementation
Add the missing closing angle bracket to the call to remove_cv. This is only used when we can't use the builtin implementation.

Fixes: 5ade17e0ca
2020-03-19 11:25:41 -07:00
zoecarver 74494d9992 [libc++] Don't use __is_fundamental in C++03 mode
In C++03 mode, nullptr is defined by libc++, not the compiler so, we can't use __is_fundamental (because it will return false for nullptr).

Fixes: 5ade17e0ca
2020-03-19 10:48:52 -07:00
zoecarver 5ade17e0ca [libc++] Use builtin type traits whenever possible
This patch updates <type_traits> to use builtin type traits whenever
possible to improve compile times.

Differential Revision: https://reviews.llvm.org/D67900
2020-03-19 09:54:53 -07:00
Yunlian Jiang 30ccc2e8d2 [libc++] Add missing visibility annotation for __base
Differential Revision: https://reviews.llvm.org/D48680
2020-03-18 17:16:00 -04:00
Atmn Patel 51b78a3e06 [libc++] Bugfix to std::binomial_distribution<int>
The current implementation of binomial_distribution is not guaranteed to
converge for certain extreme configurations of the engine and distribution.
This is due to a mistake in the implementation of the algorithm from the
given reference paper. The algorithm in the paper is guaranteed to
terminate but has redundant statements. The current implementation
simplified away the redundancy into a while loop, but it excludes the
return condition of the case where a good sample cannot be returned for
the particular sample being used from the uniform distribution, which is
what causes the infinite loop. This change guarantees termination by
recognizing that a good sample cannot be returned and returning 0 after
breaking the loop. This is also in contrast to the paper because the
return value as specified in the paper violates basic checks in at least
a subset of the extreme cases where the current implementation fails to
terminate. This default return value of 0 is satisfactory for the
extreme case known so far.

Since this is only meant to affect extreme cases where the algorithm
does not terminate anyways, the behavior is expected to remain exactly
the same for all non-extreme cases that have been terminating so far.

Fixes https://llvm.org/PR44847

Differential Revision: https://reviews.llvm.org/D74997
2020-03-17 15:56:16 -04:00
Dimitry Andric 585a3cc31b Fix -Wdeprecated-copy-dtor and -Wdeprecated-dynamic-exception-spec warnings.
Summary:
The former are like:

libcxx/include/typeinfo:322:11: warning: definition of implicit copy constructor for 'bad_cast' is deprecated because it has a user-declared destructor [-Wdeprecated-copy-dtor]
  virtual ~bad_cast() _NOEXCEPT;
          ^
libcxx/include/typeinfo:344:11: note: in implicit copy constructor for 'std::bad_cast' first required here
    throw bad_cast();
          ^

Fix these by adding an explicitly defaulted copy constructor.

The latter are like:

libcxx/include/codecvt:105:37: warning: dynamic exception specifications are deprecated [-Wdeprecated-dynamic-exception-spec]
    virtual int do_encoding() const throw();
                                    ^~~~~~~

Fix these by using the _NOEXCEPT macro instead.

Reviewers: EricWF, mclow.lists, ldionne, #libc

Reviewed By: EricWF, #libc

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D76150
2020-03-17 18:59:54 +01:00
Marek Kurdej 05343588e3 [libc++] [P0646] Add feature-test macro for __cpp_lib_list_remove_return_type.
Summary: The return type modification has already been implemented in rL364840 and rL365290.

Reviewers: ldionne, mclow.lists, EricWF, #libc!

Reviewed By: ldionne

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70275
2020-03-12 11:06:49 +01:00
Louis Dionne a13417352a [libc++] Properly mark std::function as deprecated in C++03
Due to Clang bug http://llvm.org/PR45151, deprecated attributes are not
picked up on partial specializations. This patch instead applies it to
the first declaration of std::function itself.
2020-03-10 17:45:39 -04:00
Martijn Vels b019c5c037 Partially inline basic_string copy constructor in UNSTABLE
Summary:
    This is a recommit of https://reviews.llvm.org/D73223 where the added function accidentally ended up inside an idef block.

    This change splits the copy constructor up inlining short initialization, and explicitly outlining long initialization into __init_copy_ctor_external() which is the externally instantiated slow path.

    For unstable ABI, this has the following changes:

    remove basic_string(const basic_string&)
    remove basic_string(const basic_string&, const Allocator&)
    add __init_copy_ctor_external(const value_type*, size_type)
    Quick local benchmark for Copy:

    Master
    ```
    ---------------------------------------------------------------
    Benchmark                    Time             CPU   Iterations
    ---------------------------------------------------------------
    BM_StringCopy_Empty       3.50 ns         3.51 ns    199326720
    BM_StringCopy_Small       3.50 ns         3.51 ns    199510016
    BM_StringCopy_Large       15.7 ns         15.7 ns     45230080
    BM_StringCopy_Huge        1503 ns         1503 ns       464896
    ```
    With this change
    ```
    ---------------------------------------------------------------
    Benchmark                    Time             CPU   Iterations
    ---------------------------------------------------------------
    BM_StringCopy_Empty       1.99 ns         2.00 ns    356471808
    BM_StringCopy_Small       3.29 ns         3.30 ns    203425792
    BM_StringCopy_Large       13.3 ns         13.3 ns     52948992
    BM_StringCopy_Huge        1472 ns         1472 ns       475136
    ```

    Subscribers: libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D75639
2020-03-04 17:52:46 -05:00
Martijn Vels 3712edb152 Revert "Partially inline basic_string copy constructor in UNSTABLE"
This reverts commit 8cf76e913b.

We are investigating why this causes compilation issues under -O3
2020-03-04 14:52:17 -05:00
Louis Dionne c030ba64e4 [libc++] Avoid deprecation warning in the implementation of __has_rebind 2020-03-04 14:38:51 -05:00
Eric Fiselier 5891e7302f [libc++] Move std::string extern template declarations to end of class.
They need to appear before any member functions are ODR used, because
they change the visibility of many of these functions and otherwise
they could end up with hidden visibility in the DSO.
2020-03-04 13:57:29 -05:00
Louis Dionne 30cbdcb5c3 [libc++] Revert to previous implementation of __has_rebind
The new implementation introduced in 5b1e5b43 broke the bot running GCC 5.
2020-03-04 13:55:35 -05:00
Michael Park 5b1e5b4338 [libc++][P0174] Deprecated/removed parts of default allocator.
Differential Revision: https://reviews.llvm.org/D70117
2020-03-04 12:06:26 -05:00
Martijn Vels 8cf76e913b Partially inline basic_string copy constructor in UNSTABLE
his change splits the copy constructor up inlining short initialization, and explicitly outlining long initialization into __init_copy_ctor_external() which is the externally instantiated slow path.

For unstable ABI, this has the following changes:

remove basic_string(const basic_string&)
remove basic_string(const basic_string&, const Allocator&)
add __init_copy_ctor_external(const value_type*, size_type)
Quick local benchmark for Copy:

Master
```
---------------------------------------------------------------
Benchmark                    Time             CPU   Iterations
---------------------------------------------------------------
BM_StringCopy_Empty       3.50 ns         3.51 ns    199326720
BM_StringCopy_Small       3.50 ns         3.51 ns    199510016
BM_StringCopy_Large       15.7 ns         15.7 ns     45230080
BM_StringCopy_Huge        1503 ns         1503 ns       464896
```

```
---------------------------------------------------------------
Benchmark                    Time             CPU   Iterations
---------------------------------------------------------------
BM_StringCopy_Empty       1.99 ns         2.00 ns    356471808
BM_StringCopy_Small       3.29 ns         3.30 ns    203425792
BM_StringCopy_Large       13.3 ns         13.3 ns     52948992
BM_StringCopy_Huge        1472 ns         1472 ns       475136
```

Author: Martijn Vels <martijn.vels@gmail.com>

Reviewers: EricWF, mclow.list

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73223
2020-03-03 17:49:25 -05:00
Martijn Vels 675326466b Add flag _LIBCPP_ABI_STRING_OPTIMIZED_EXTERNAL_INSTANTIATIONS for basic_string ABI
Summary: This review is a mostly trivial change to use an explicit ABI flag for the unstable external template list. This follows the practice for an ABI flag per feature, and provides a spot for the rational / motivation for the flag.

Reviewers: EricWF, ldionne

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75457
2020-03-02 10:26:37 -05:00
Martijn Vels f87d30cba2 Partially inline basic_string::operator=(const basic_string&)
Summary:
This change partially inlines operator=(const basic_string&) where both the input and current instance are short strings, making the assignment a fixed length inlined memcpy.

Assignments where either of the strings are long are delegate to __assign_no_alias<__is_short>(), which is templated for the long / short branch already observed in the caller.

Stable:
```
--------------------------------------------------------------------------------
Benchmark                                     Time             CPU   Iterations
--------------------------------------------------------------------------------
BM_StringAssignStr_Empty_Opaque            2.65 ns         2.66 ns    263745536
BM_StringAssignStr_Empty_Transparent       2.95 ns         2.96 ns    236494848
BM_StringAssignStr_Small_Opaque            2.93 ns         2.94 ns    237301760
BM_StringAssignStr_Small_Transparent       2.69 ns         2.69 ns    265809920
BM_StringAssignStr_Large_Opaque            19.6 ns         19.6 ns     35573760
BM_StringAssignStr_Large_Transparent       19.1 ns         19.1 ns     36716544
BM_StringAssignStr_Huge_Opaque             1901 ns         1901 ns       364544
BM_StringAssignStr_Huge_Transparent        1889 ns         1889 ns       360448
```

Unstable
```
--------------------------------------------------------------------------------
Benchmark                                     Time             CPU   Iterations
--------------------------------------------------------------------------------
BM_StringAssignStr_Empty_Opaque            1.29 ns         1.29 ns    540454912
BM_StringAssignStr_Empty_Transparent       1.11 ns         1.12 ns    628482048
BM_StringAssignStr_Small_Opaque            1.29 ns         1.29 ns    541216768
BM_StringAssignStr_Small_Transparent       1.11 ns         1.11 ns    629469184
BM_StringAssignStr_Large_Opaque            15.6 ns         15.6 ns     44945408
BM_StringAssignStr_Large_Transparent       14.9 ns         14.9 ns     46764032
BM_StringAssignStr_Huge_Opaque             1713 ns         1713 ns       401408
BM_StringAssignStr_Huge_Transparent        1704 ns         1704 ns       397312

```

Subscribers: libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75211
2020-03-02 09:58:11 -05:00
ogiroux 621388468b Some fixes for open breaks on MacOS and UBSan 2020-02-26 20:51:19 -08:00
Louis Dionne a0ec111c92 [libc++] Temporarily disable availability markup for the C++20 Synchronization library
The markup wasn't quite right, and that broke compilation with availability
markup enabled. I'm disabling it until I have time to fix it properly to
get the CI mostly green again.
2020-02-26 19:10:27 -05:00
Martijn Vels d260ea7199 Inline basic_string::erase for fastpath where __n == npos
Summary:
This change checks for the case where people want to erase a string to the end, i.e., __n == npos, and inlines the call if so.

This also demonstrates keeping the ABI intact for V1, but inlining the erase() method for unstable.

Reviewers: EricWF, mclow.lists, ldionne

Reviewed By: EricWF, ldionne

Subscribers: smeenai, dexonsmith, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73743
2020-02-26 13:37:45 -05:00
Mikhail Maltsev 14aef5367d [libcxx] Fix _LIBCPP_HAS_THREAD_API_EXTERNAL build
Summary:
The definition of `__libcpp_timed_backoff_policy` and the declaration of
`__libcpp_thread_poll_with_backoff` must not be guarded by
  #if !defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
because the definitions of `__libcpp_timed_backoff_policy::operator()`
and `__libcpp_thread_poll_with_backoff` aren't guarded by this macro
(and this is correct because these two functions are implemented in
terms of other libc++ functions and don't interact with the host
threading library).

Reviewers: ldionne, __simt__, EricWF, mclow.lists

Reviewed By: ldionne

Subscribers: dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75191
2020-02-26 17:54:43 +00:00
Martijn Vels 07eb82fc06 Add _LIBCPP_BUILTIN_CONSTANT_P support.
Summary:
This change adds the macros _LIBCPP_COMPILER_HAS_BUILTIN_CONSTANT and _LIBCPP_BUILTIN_CONSTANT_P to detect compile time constants, and optimze the code accordingly.

A planned usage example:
The implementation of basic_string::assign() can short-cut a compile time known short string assignent into a fast and compact inlined assignment:

```
basic_string::assign(const value_type* __s) {
  if (_LIBCPP_BUILTIN_CONSTANT_P(__s[0]) && length(__s) < __min_cap) {
    copy(pointer(), _s, length(__s) + 1);
    set_size(length(__s));
  } else {
    // delegate / tail call out of line implementation
  }
}
```

Subscribers: christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73732
2020-02-26 11:03:51 -05:00
zoecarver 28d38a25e9 Remove std::shared_ptr::allocate_shared
std::shared_ptr::allocate_shared isn't in the standard. This commit removes it from libc++. It updates std::allocate_shared to use __create_with_cntrl_block.

Differential Revision: https://reviews.llvm.org/D66178
2020-02-25 16:50:57 -08:00
Louis Dionne 3b5530cf96 [libc++] Avoid including <semaphore.h> on Apple
It turns out that <semaphore.h> is not well-behaved, as it transitively
includes <sys/param.h>, and that one defines several non-reserved macros
that clash with some downstream projects in modular builds. For the time
being, using <sys/semaphore.h> instead gives us the declarations we need
without the macros.

rdar://59744472
2020-02-25 17:52:34 -05:00
Martin Storsjö e3add3e5a1 [libcxx] Fix building for windows after 54fa9ecd30
Move the implementation of __libcpp_thread_poll_with_backoff
and __libcpp_timed_backoff_policy::operator() out of the
_LIBCPP_HAS_THREAD_API_PTHREAD block. None of the code in these
methods is pthreads specific.

Also add "inline _LIBCPP_INLINE_VISIBILITY" to
__libcpp_timed_backoff_policy::operator(), to avoid errors due to
multiple definitions of the operator. Contrary to
__libcpp_thread_poll_with_backoff (which is a template function),
this is a normal non-templated method.

Differential Revision: https://reviews.llvm.org/D75102
2020-02-25 21:33:52 +02:00
Louis Dionne 7c2f4a8370 [libc++] Revert 03dd205c15 "Adjust max_align_t handling"
That commit was made without approval from a libc++ reviewer, and it
also broke the build in C++03 mode.
2020-02-25 11:42:08 -05:00
Louis Dionne ab41129b1e [libc++] Proper fix for libc++'s modulemap after D68480
Summary:
In libc++, we normally #ifdef out header content instead of #erroring
out when the Standard in use is insufficient for the requirements of
the header.

Reviewers: EricWF

Subscribers: jkorous, dexonsmith, libcxx-commits, teemperor

Tags: #libc

Differential Revision: https://reviews.llvm.org/D75074
2020-02-25 11:31:10 -05:00
Joerg Sonnenberger 03dd205c15 Adjust max_align_t handling
Depend on the compiler to provide a correct implementation of
max_align_t. If __STDCPP_NEW_ALIGNMENT__ is missing and C++03 mode has
been explicitly enabled, provide a minimal fallback in <new> as
alignment of the largest primitive types.
2020-02-25 01:36:43 +01:00
Raphael Isemann b61e83eb0e [libc++] Give headers that require C++14 a cplusplus14 requires in the modulemap
https://reviews.llvm.org/D68480 added those headers and made the std module
only usable with C++14 or later as the submodules were not marked as requiring
C++14 or later. This just adds the missing requires directives.
2020-02-24 20:20:55 +01:00
Louis Dionne b21405d1cd [libc++] Fix CI and Linux failures after landing D68480
- Avoid using C++11-and-later features in <atomic>:
  Historically, we've supported <atomic> in C++03, so we can't use C++11
  features in that header. This is something we really need to change,
  since our implementation of <atomic> is starting to accumulate technical
  debt because of that.
- Mark a test as unsupported on single threaded systems
- Add missing symbols to the Linux ABI list
2020-02-24 11:58:25 -05:00
Louis Dionne c008716417 [libc++] Mark the C++03 version of std::function as deprecated
Summary: We want to eventually remove it.

Reviewers: EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74719
2020-02-24 10:59:58 -05:00
Louis Dionne 80e73f2295 [libc++] Adapt a few things around the implementation of P1135R6
- Add the new symbols to the ABI list on Darwin
- Add XFAIL markup to the tests that require dylib support on older platforms
- Add availability markup for back-deployment
2020-02-24 10:59:35 -05:00
Olivier Giroux 54fa9ecd30 [libc++] Implementation of C++20's P1135R6 for libcxx
Differential Revision: https://reviews.llvm.org/D68480
2020-02-24 10:59:35 -05:00
Martijn Vels d8969a1cb9 Split _LIBCPP_STRING_EXTERN_TEMPLATE_LIST up into a V1 and UNSTABLE version.
This change splits the _LIBCPP_STRING_EXTERN_TEMPLATE_LIST up into a _LIBCPP_STRING_V1_EXTERN_TEMPLATE_LIST containing the stable ABI, and a _LIBCPP_STRING_UNSTABLE_EXTERN_TEMPLATE_LIST containing the unstable ABI.

The purpose is to explicitly define and maintain the two lists, where the unstable ABI allows for ABI breaking changes for purposes such as optimization while offering a strong guarantee that any change inside the unstable ABI does not affect the stable ABI.

As per the comment in the __string header, we do still allow etries to be added to the stable ABI list as the c++ versions and corresponding c++ std API changes.
2020-02-20 23:21:14 -05:00
Mark de Wever 72ce0c8073 [libc++][regex] Validate backreferences in the constructor.
This patch enables throwing exceptions for invalid backreferences
in the constructor when using the basic, extended,  grep, or egrep grammar.

This fixes bug 34297.

Differential Revision: https://reviews.llvm.org/D62453
2020-02-20 18:16:21 -05:00
Logan Smith 092a57f508 [libc++] Fix unqualified call to 'ref' inside shared_ptr(unique_ptr<U, D>)
This prevents unintended ADL: https://gcc.godbolt.org/z/EHw3Gy
This issue was mentioned as an addendum in PR44398.

Differential Revision: https://reviews.llvm.org/D74289
2020-02-20 12:24:40 -05:00
Logan Smith e442f38395 [libc++] Fix unintended ADL inside ref(reference_wrapper<T>) and cref(reference_wrapper<T>)
This patch qualifies calls to ref and cref inside ref(reference_wrapper<T>)
and cref(reference_wrapper<T>), respectively. These previously unqualified
calls could break in the presence of user functions called ref/cref inside
associated namespaces: https://gcc.godbolt.org/z/8VfprT

Fixes PR44398.

Differential Revision: https://reviews.llvm.org/D74287
2020-02-20 12:22:21 -05:00
Louis Dionne c3478eff7a [libc++] reduce <complex> parsing time
Instead of including <ios> for ios_base::failbit, simply get failbit
member of the template argument. Print directly to a stream instead
of using intermediate ostringstream.

    Parsing time: 874ms -> 164ms (-81%)

Thanks to Nikita Kniazev for the patch!

Differential Revision: https://reviews.llvm.org/D71214
2020-02-19 16:09:41 -05:00
Louis Dionne 6ba2d7b166 [libc++] Fixes backreferences for extended grammar.
The regex backreferences were not properly parsed and used when using
the extended grammar. This change parses them. The issue was found while
working on PR34297.

Thanks to Mark de Wever for the patch!

Differential Revision: https://reviews.llvm.org/D62451
2020-02-19 15:57:16 -05:00
Eric Fiselier a829443cc7 [libc++] Fix ABI break in __bit_reference.
The libc++ __bit_iterator type has weird ABI calling conventions as a
quirk
of the implementation. The const bit iterator is trivial, but the
non-const
bit iterator is not because it declares a user-defined copy constructor.

Changing this now is an ABI break, so this test ensures that each type
is trivial/non-trivial as expected.

The definition of 'non-trivial for the purposes of calls':
  A type is considered non-trivial for the purposes of calls if:
      * it has a non-trivial copy constructor, move constructor, or
            destructor, or
	        * all of its copy and move constructors are deleted.
2020-02-19 12:02:06 -05:00
Raphael Isemann 23368bee15 Revert "[libc++] Move abs and div into stdlib.h to fix header cycle."
This reverts commit 82b47b2978.

This broke Clang and LLDB module builds without -fmodules-local-submodule-visbility.
I'll revert this for now until we have a fix and reland once Clang
can properly handle this code.

See also the discussion in https://reviews.llvm.org/rG82b47b2978405f802a33b00d046e6f18ef6a47be
2020-02-17 17:59:08 +01:00
Louis Dionne 8b60ba73af [libc++] Add availability markup for std::to_chars on Apple platforms
Summary:
Otherwise, one gets link errors when trying to back-deploy to older platforms.

rdar://problem/57854364

Reviewers: lichray, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D74626
2020-02-17 09:32:46 -05:00
Eric Fiselier 82b47b2978 [libc++] Move abs and div into stdlib.h to fix header cycle.
libc++ is careful to not fracture overload sets. When one overload
is visible to a user, all of them should be. Anything less causes
subtle bugs and ODR violations.

Previously, in order to support ::abs and ::div being supplied by
both <cmath> and <cstdlib> we had to do awful things that make
<math.h> and <stdlib.h> have header cycles and be non-modular.
This really breaks with modules.

Specifically the problem was that in C++ ::abs introduces overloads
for floating point numbers, these overloads forward to ::fabs,
which are defined in math.h. Therefore ::abs needed to be in math.h
too. But this required stdlib.h to include math.h and math.h to
include stdlib.h.

To avoid these problems the definitions have been moved to stddef.h
(which math includes), and the floating point overloads of ::abs
have been changed to call __builtin_fabs, which both Clang and GCC
support.
2020-02-15 18:55:07 -05:00
Eric Fiselier cccf1ef0c8 [libc++] Remove cycle between <type_traits> and <cstddef>
This was caused by byte depending on traits. This patch moves
the minimal amount of meta-programming into <cstddef> to break the cycle.
2020-02-14 17:36:27 +01:00
Eric Fiselier e337fb0790 add type_traits include as required for std::integral_constant 2020-02-14 16:38:28 +01:00
Louis Dionne 0a0e0afaa0 [libc++] span: Fix incorrect static asserts
The static asserts in span<T, N>::front() and span<T, N>::back() are
incorrect as they may be triggered from valid code due to evaluation
of a never taken branch:

    span<int, 0> foo;
    if (!foo.empty()) {
        auto x = foo.front();
    }

The problem is that the branch is always evaluated by the compiler,
creating invalid compile errors for span<T, 0>.

Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D71995
2020-02-14 14:32:41 +01:00
Louis Dionne b5abd50f06 [libc++] span: Guard against overflow in span::subspan
The calculation _Offset + _Count <= size() may overflow, so use
_Count <= size() - _Offset instead. Note that this is safe due to
the previous constraint that _Offset <= size().

Patch by Michael Schellenberger Costa.

Differential Revision: https://reviews.llvm.org/D71998
2020-02-12 16:21:46 +01:00
Louis Dionne 37f46650c3 [libc++] Make sure that vector copy-construction is disabled for non-copyable types
The Standard requires the value_type of the vector to be Cpp17CopyInsertable
in order for copy-construction to be enabled:

	http://eel.is/c++draft/container.requirements#tab:container.req

rdar://problem/56674564

Differential Revision: https://reviews.llvm.org/D74251
2020-02-11 17:12:16 +01:00
Louis Dionne 92a1f65f17 [libc++] span: Fix incorrect return type of span::subspan
The extent of the returned span was always std::dynamic_extent, which
is incorrect.

Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D71997
2020-02-11 11:58:45 +01:00
Louis Dionne b4a3e6b664 [libcxx] span: Remove unneeded comparison
size_t is always greater than 0, so remove the artifact from the old
index_type.

Patch by Michael Schellenberger Costa.

Differential Revision: https://reviews.llvm.org/D71996
2020-02-11 11:39:12 +01:00
Louis Dionne edbaa7fc04 [libc++] span: Cleanup includes
Thanks to Michael Schellenberger Costa for the patch.

Differential Revision: https://reviews.llvm.org/D72036
2020-02-11 11:17:30 +01:00
Louis Dionne 9fda213d62 [libcxx] Qualify make_move_iterator in vector::insert for input iterators
Unqualified calls to make_move_iterator in the vector::insert overload
for input iterators lead to ADL issues: https://gcc.godbolt.org/z/bmcNbh

Patch by Logan Smith.

Differential Revision: https://reviews.llvm.org/D74290
2020-02-11 11:00:45 +01:00
Louis Dionne 1ac44d9fd1 [libc++] Protect <span> against min/max macro
Patch by Corentin Jabot
Differential Revision: https://reviews.llvm.org/D73855
2020-02-10 13:41:34 +01:00
Marek Kurdej e93e58c6c4 Reland [libc++] [P0325] Implement to_array from LFTS with updates.
Fixed expected errors and notes.

Summary:
This patch implements https://wg21.link/P0325.

Reviewers: EricWF, mclow.lists, ldionne, lichray

Reviewed By: ldionne, lichray

Subscribers: lichray, dexonsmith, zoecarver, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69882
2020-01-31 11:47:18 +01:00
Marek Kurdej 5e7017273f Revert "[libc++] [P0325] Implement to_array from LFTS with updates."
This reverts commit 86aae78268.

A test is failing on "Release" build without assertions enabled (Fedora 31 on x86_64).
2020-01-31 09:45:50 +01:00
Martijn Vels 282b803b62 White space only change: reflow a comment in basic_string
Summary: This change reflows a comment line. This change serves as a no-op test commit

Reviewers: mclow.lists, ldionne, EricWF

Subscribers: dexonsmith, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D73552
2020-01-30 19:55:48 -05:00
Marek Kurdej 86aae78268 [libc++] [P0325] Implement to_array from LFTS with updates.
Summary:
This patch implements https://wg21.link/P0325.
Please mind that at it is my first contribution to libc++, so I may have forgotten to abide to some conventions.

Reviewers: EricWF, mclow.lists, ldionne, lichray

Reviewed By: ldionne, lichray

Subscribers: lichray, dexonsmith, zoecarver, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69882
2020-01-30 13:38:37 +01:00
Dimitry Andric 5e416ba943 Define _LIBCPP_HAS_TIMESPEC_GET for FreeBSD when appropriate
Summary:
FreeBSD got `timespec_get` support somewhere in the 12.x timeframe, but
the C++ version check in its system headers was written incorrectly.
This has now been fixed for both FreeBSD 13 and 12.

Add checks for the corresponding `__FreeBSD_version` values, to define
`_LIBCPP_HAS_TIMESPEC_GET` when the function is supported.

Reviewers: emaste, EricWF, ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: arichardson, krytarowski, christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D71522
2020-01-30 08:00:56 +01:00
Martin Storsjö 7db4f2c694 [libcxx] [Windows] Store the lconv struct returned from localeconv in locale_t
This fixes using non-default locales, which currently can crash when
e.g. formatting numbers.

Within the localeconv_l function, the per-thread locale is temporarily
changed with __libcpp_locale_guard, then localeconv() is called,
returning an lconv * struct pointer.

When localeconv_l returns, the __libcpp_locale_guard dtor restores
the per-thread locale back to the original. This invalidates the
contents of the earlier returned lconv struct, and all C strings
that are pointed to within it are also invalidated.

Thus, to have an actually working localeconv_l function, the
function needs to allocate some sort of storage for the returned
contents, that stays valid for as long as the caller needs to use
the returned struct.

Extend the libcxx/win32 specific locale_t class with storage for
a deep copy of a lconv struct, and change localeconv_l to take
a reference to the locale_t, to allow it to store the returned
lconv struct there.

This works fine for libcxx itself, but wouldn't necessarily be right
for a caller that uses libcxx's localeconv_l function.

This fixes around 11 of libcxx's currently failing tests on windows.

Differential Revision: https://reviews.llvm.org/D69505
2020-01-29 22:37:11 +02:00
David Zarzycki 5dda92fcb0
Add test for spaceship operator to __config
Summary:
The libcxx test suite auto-detects spaceship operator, but __config does not. This means that the libcxx test suite has been broken for over a month when using top-of-tree clang. This also really ought to be fixed before 10.0.

See: bc633a42dd

Reviewers: chandlerc, mclow.lists, EricWF, ldionne, CaseyCarter

Reviewed By: EricWF

Subscribers: broadwaylamb, hans, dexonsmith, tstellar, llvm-commits, libcxx-commits

Tags: #libc, #llvm

Differential Revision: https://reviews.llvm.org/D72980
2020-01-24 13:27:22 -05:00
Louis Dionne 8ae404a2f6 [libc++] Make sure std::is_scalar returns true for block types
Summary:
The compiler already treats them as scalar types, so the library should
too. Furthermore, this allows blocks to be used in more places, for
example in std::optional, which requires an object type.

rdar://problem/57892832

Reviewers: dexonsmith, EricWF, mclow.lists
Differential Revision: https://reviews.llvm.org/D72708
2020-01-21 17:15:15 -08:00
Eric Fiselier fa40b41168 Revert "[libc++] Optimize / partially inline basic_string copy constructor"
This reverts commit a8a9c8e0a1.

There are multiple reported failures caused by this change.
Each failure is really weird, but it makes sense to revert
while investigating.
2020-01-20 21:41:58 -05:00
Eric Fiselier a8a9c8e0a1 [libc++] Optimize / partially inline basic_string copy constructor
Splits copy constructor up inlining short initialization, outlining long
initialization into __init_long() which is the externally instantiated slow
path initialization.

Subsequently changing the copy ctor to be inlined (not externally instantiated)
provides significant speed ups for short string initialization.

Generated code given:

void StringCopyCtor(void* mem, const std::string& s) {
    std::string*p = new(mem) std::string{s};
}

asm:
        cmp     byte ptr [rsi + 23], 0
        js      .LBB0_2
        mov     rax, qword ptr [rsi + 16]
        mov     qword ptr [rdi + 16], rax
        movups  xmm0, xmmword ptr [rsi]
        movups  xmmword ptr [rdi], xmm0
        ret
.LBB0_2:
        jmp     std::basic_string::__init_long # TAILCALL

Benchmark:
BM_StringCopy_Empty                                           5.19ns ± 6%             1.50ns ± 8%  -71.02%        (p=0.000 n=10+10)
BM_StringCopy_Small                                           5.14ns ± 8%             1.53ns ± 7%  -70.17%        (p=0.000 n=10+10)
BM_StringCopy_Large                                           18.9ns ± 0%             19.3ns ± 0%   +1.92%        (p=0.000 n=10+10)
BM_StringCopy_Huge                                             309ns ± 1%              316ns ± 5%     ~            (p=0.633 n=8+10)

Patch from Martijn Vels (mvels@google.com)
Reviewed as D72160.
2020-01-17 16:53:54 -05:00
Petr Hosek 9050d0fb59 [libcxx] Temporarily switch back to pthread backend for Fuchsia
We switched to C11 thread API on Fuchsia in ab9aefe, but further
testing showed that Fuchsia's C11 mutex implementation needs a few
improvements for this to be usable, so we temporarily switch back
to the pthread implementation until those issues are addressed.

Differential Revision: https://reviews.llvm.org/D72862
2020-01-16 14:53:08 -08:00
Eric Fiselier 59919c4d6b [libc++] Fix Windows DLL build for string.
We need to mark string::npos with _LIBCPP_FUNC_VIS on the first
in-class declaration, otherwise it might get ignored
2020-01-16 15:01:12 -05:00
Petr Hosek 3481e5d7ed [libcxx] Use mtx_plain | mtx_recursive following C11 API
The C11 API specifies that to initialize a recursive mutex,
mtx_plain | mtx_recursive should be used with mtx_init.

Differential Revision: https://reviews.llvm.org/D72809
2020-01-15 15:15:39 -08:00
Eric Fiselier 313d89724c [libc++] Fix parsing <string> in C++03.
Specifically, add a space between >> when closing templates.
2020-01-15 17:29:55 -05:00
Eric Fiselier 58c7fa5ade [libc++] Optimize basic_string::operator=(const basic_string&) for SSO assignments
This change optimizes the operator=() assignment for short strings by direcly
copying the raw data from the source into the current instance. This creates an
optimized / inlined mempcy up to over 2X faster for short string assignments.
With inlining enabled for operator=, performance is up to 6X faster.

Benchmarks 'as is':
name                                    old time/op   new time/op    delta
BM_StringAssignStr_Empty_Opaque         6.05ns ± 2%   3.59ns ± 0%  -40.67%
BM_StringAssignStr_Empty_Transparent    5.15ns ± 0%   3.08ns ± 0%  -40.12%
BM_StringAssignStr_Small_Opaque         7.71ns ± 0%   3.59ns ± 0%  -53.45%
BM_StringAssignStr_Small_Transparent    7.66ns ± 0%   3.09ns ± 0%  -59.66%
BM_StringAssignStr_Large_Opaque         24.1ns ± 0%   24.9ns ± 0%   +3.22%
BM_StringAssignStr_Large_Transparent    22.2ns ± 0%   22.8ns ± 0%   +2.77%
BM_StringAssignStr_Huge_Opaque           315ns ± 6%    320ns ± 5%     ~
BM_StringAssignStr_Huge_Transparent      318ns ± 5%    321ns ± 4%     ~

Benchmarks with partial inlining operator=():
name                                    old time/op   new time/op    delta
BM_StringAssignStr_Empty_Opaque         5.94ns ± 2%   1.95ns ± 0%  -67.21%
BM_StringAssignStr_Empty_Transparent    5.14ns ± 0%   1.04ns ± 1%  -79.73%
BM_StringAssignStr_Small_Opaque         7.69ns ± 0%   1.96ns ± 0%  -74.48%
BM_StringAssignStr_Small_Transparent    7.65ns ± 0%   1.04ns ± 0%  -86.40%
BM_StringAssignStr_Large_Opaque         24.1ns ± 0%   24.5ns ± 0%   +1.61%
BM_StringAssignStr_Large_Transparent    22.2ns ± 0%   21.1ns ± 0%   -4.70%
BM_StringAssignStr_Huge_Opaque           317ns ± 5%    323ns ± 4%     ~
BM_StringAssignStr_Huge_Transparent      318ns ± 5%    320ns ± 5%     ~

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D72704
2020-01-15 17:27:10 -05:00
Eric Fiselier 288a143639 [libc++] Explicitly enumerate std::string external instantiations - Attempt 2
The GCC build failures have been addressed, and the LLDB failures were
  fixed by LLDB.

   I have also verified that the apple-clang 9.0 segfault no longer
   occurs.

Original Message:

 The external instantiation of std::string is a problem for libc++.
    Additions and removals of inline functions in string can cause ABI
    breakages, including introducing new symbols.

    This patch aims to:
      (1) Make clear which functions are explicitly instatiated.
      (2) Prevent new functions from being accidentally instantiated.
      (3) Allow a migration path for adding or removing functions from the
      explicit instantiation over time.

    Although this new formulation is uglier, it is preferable from a
    maintainability and readability standpoint because it explicitly
    enumerates the functions we've chosen to expose in our ABI. Changing
    this list is non-trivial and requires thought and planning.

    (3) is achieved by making it possible to control the extern template declaration
    separately from it's definition. Meaning we could add a new definition to
    the dylib, wait for it to roll out, then add the extern template
    declaration to the header. Similarly, we could remove existing extern
    template declarations while still keeping the definition to prevent ABI
    breakages.
2020-01-15 17:12:49 -05:00
Eric Fiselier 2d8f23f571 [libc++] Explicitly mark basic_string<...>::npos with default
visibility.

This ensures that the version compiled into the library isn't
accidentally hidden.
2020-01-15 17:02:17 -05:00
Eric Fiselier 24d2a015ea [libc++] Make SFINAE'd member functions in string mutually exclusive.
This patch is needed in order to work around a GCC bug that fails to
explicitly instantiate a non-template function of a class template when
there is another overload that's a function template.
(See https://godbolt.org/z/4bUQ_b)

This patch SFINAE's away the function templates when the argument is
a basic_string.
2020-01-15 17:00:26 -05:00
Hans Wennborg 5852475e2c Bump the trunk major version to 11
and clear the release notes.
2020-01-15 13:38:01 +01:00
Petr Hosek ab9aefee9f [libcxx] Use C11 thread API on Fuchsia
On Fuchsia, pthread API is emulated on top of C11 thread API. Using C11
thread API directly is more efficient.

While this implementation is only used by Fuchsia at the moment, it's
not Fuchsia specific, and could be used by other platforms that use C11
threads rather than pthreads in the future.

Differential Revision: https://reviews.llvm.org/D64378
2020-01-14 16:48:20 -08:00
Martin Storsjö 337e435964 [libcxx] [Windows] Make a more proper implementation of strftime_l for mingw with msvcrt.dll
This also makes this function consistent with the rest of the
libc++ provided fallbacks.

The locale support in msvcrt.dll is very limited anyway; it can
only be configured processwide, not per thread, and it only seems
to support the locales "C" and "" (the user set locale), so it's
hard to make any meaningful automatic test for it. But manually tested,
this change does make time formatting locale code in libc++ output
times in the user requested format, when using locale "".

Differential Revision: https://reviews.llvm.org/D69554
2020-01-14 22:29:47 +02:00
Oliver Stannard 6a634a5dba Revert "[libc++] Explicitly enumerate std::string external instantiations."
This is causing failures for multiple buildbots and bootstrap builds,
details at https://reviews.llvm.org/rG61bd1920.

This reverts commit 61bd19206f.
2020-01-13 13:54:04 +00:00
Eric Fiselier 61bd19206f [libc++] Explicitly enumerate std::string external instantiations.
The external instantiation of std::string is a problem for libc++.
    Additions and removals of inline functions in string can cause ABI
    breakages, including introducing new symbols.

    This patch aims to:
      (1) Make clear which functions are explicitly instatiated.
      (2) Prevent new functions from being accidentally instantiated.
      (3) Allow a migration path for adding or removing functions from the
      explicit instantiation over time.

    Although this new formulation is uglier, it is preferable from a
    maintainability and readability standpoint because it explicitly
    enumerates the functions we've chosen to expose in our ABI. Changing
    this list is non-trivial and requires thought and planning.

    (3) is achieved by making it possible to control the extern template declaration
    separately from it's definition. Meaning we could add a new definition to
    the dylib, wait for it to roll out, then add the extern template
    declaration to the header. Similarly, we could remove existing extern
    template declarations while still keeping the definition to prevent ABI
    breakages.
2020-01-09 15:51:02 -05:00
Kazuaki Ishizaki 9de6a39872 [libcxx] fix incorrect attribute property
Summary:
`__has_attribute(fallthough)` -> `__has_attribute(fallthrough)`
This is a follow-up of https://reviews.llvm.org/D72287

Reviewers: EricWF, mclow.lists, Jim

Reviewed By: Jim

Subscribers: christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D72314
2020-01-08 09:35:26 +08:00
Ruslan Baratov 6e8659c351 [libc++] Fix typo in std::midpoint
Reviewed By: mclow.lists

Differential Revision: https://reviews.llvm.org/D71525
2019-12-21 01:26:24 -08:00
Michał Górny e1882af9f6 [libc++] Update feature list for NetBSD
Add NetBSD to the same feature list as Fuchsia since it matches
in available features, effectively enabling aligned_alloc(),
timespec_get() and C11 features.  Remove now-duplicate declaration
of quick_exit() support.

Differential Revision: https://reviews.llvm.org/D71511
2019-12-20 17:50:47 +01:00
Eric Fiselier a53534a9f6 [libc++] Add __default_init_tag to basic_string constructors
This removes unneeded zero initialization of string data.

For example, given the below code:

void Init(void *mem) {
    new (mem) std::string("Hello World");
}

Assembly before:

Init(void*):
        xorps   xmm0, xmm0
        movups  xmmword ptr [rdi], xmm0
        mov     qword ptr [rdi + 16], 0
        mov     byte ptr [rdi], 22
        movabs  rax, 8022916924116329800
        mov     qword ptr [rdi + 1], rax
        mov     dword ptr [rdi + 8], 1684828783
        mov     byte ptr [rdi + 12], 0
        ret

Assembly after:

Init():
        mov     byte ptr [rdi], 22
        movabs  rax, 8022916924116329800
        mov     qword ptr [rdi + 1], rax
        mov     dword ptr [rdi + 8], 1684828783
        mov     byte ptr [rdi + 12], 0
        ret

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D70621
2019-12-16 19:04:09 -05:00
Eric Fiselier 549545b64a [libc++] Rework compressed pair constructors.
This patch de-duplicates most compressed pair constructors
to use the same code in C++11 and C++03.

Part of doing that is deleting the "__second_tag()" and replacing
it with a "__value_init_tag()" which has the same effect, but
allows for the removal of the special "one-arg" first element
constructor.

This patch is intended to have no semantic change.
2019-12-16 18:38:58 -05:00
Eric Fiselier 0fa118a9da Add default initialization to compressed_pair.
This change introduces the __default_init_tag to memory, and a corresponding
element constructor to allow for default initialization of either of the pair
values. This is useful for classes such as std::string where most (all)
constructors explicitly initialize the values in the constructor.

Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D70617
2019-12-16 17:14:02 -05:00
Eric Fiselier fda3825c7a [libc++] Ensure __config always defines certain configuration macros. 2019-12-13 15:42:07 -05:00
Eric Fiselier f97936fabd [libc++] Cleanup and enable multiple warnings.
Too many warnings are being disabled too quickly. Warnings are
important to keeping libc++ correct. This patch re-enables two
warnings: -Wconstant-evaluated and -Wdeprecated-copy.

In future, all warnings disabled for the test suite should require
an attached bug. The bug should state the plan for re-enabling that
warning, or a strong case why it should remain disabled.
2019-12-12 21:09:08 -05:00
Fangrui Song b7eb30d481 __bit_reference: fix -Wdeprecated-copy warnings
Since C++11, [depr.impldec]:

The implicit definition of a copy constructor as defaulted is deprecated
if the class has a user-declared copy assignment operator or a
user-declared destructor.

At clang HEAD, -Wdeprecated-copy (included by -Wextra) will warn on such instances.

Reviewed By: EricWF

Differential Revision: https://reviews.llvm.org/D71096
2019-12-12 16:31:36 -08:00
Eric Christopher fa0fc04a4f Temporarily Revert "[libc++] Fix -Wdeprecated-copy warnings in __bit_reference"
as it's causing test failures due to mismatched visibility.

This reverts commit 02bb20223b.
2019-12-12 00:22:37 -08:00
Eric Christopher 02bb20223b [libc++] Fix -Wdeprecated-copy warnings in __bit_reference
Add a couple of default copy constructors to fix the warning.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D71395
2019-12-11 23:50:28 -08:00
Louis Dionne dd37e24ae6 [libc++] Hide some functions and types in <future> and <thread> as hidden
Otherwise, weak symbols leak into user programs when using `async` with
non-internal types.
2019-12-10 19:19:45 -05:00
marshall 703c26f03b Optimize and fix basic_string move assignment operator. Reviewed as https://reviews.llvm.org/D68623. Thanks to mvels for the patch. 2019-11-27 07:13:32 -08:00
Shoaib Meenai d018b556c7 [libcxx] Omit unneeded locale fallbacks on Android 21+
Android API level 21 and above have all these functions available, so we
don't need to include our fallback definitions.

Differential Revision: https://reviews.llvm.org/D69983
2019-11-25 11:06:08 -08:00
Dan Albert 19fd9039ca Fix _LIBCPP_HAS_ definitions for Android.
Summary:
Android added quick_exit()/at_quick_exit() in API level 21,
aligned_alloc() in API level 28, and timespec_get() in API level 29,
but has the other C11 features at all API levels (since they're basically
just coming from clang directly).

_LIBCPP_HAS_QUICK_EXIT and _LIBCPP_HAS_TIMESPEC_GET already existed,
so we can reuse them. (And use _LIBCPP_HAS_TIMESPEC_GET in a few more
places where _LIBCPP_HAS_C11_FEATURES has been used as a proxy. This
isn't correct for Android.)

_LIBCPP_HAS_ALIGNED_ALLOC is added, to cover aligned_alloc() (obviously).

Add a missing std:: before aligned_alloc in a cstdlib test, and remove a
couple of !defined(_WIN32)s now that we're explicitly testing
TEST_HAS_ALIGNED_ALLOC rather than TEST_HAS_C11_FEATURES.

Reviewers: danalbert, EricWF, mclow.lists

Reviewed By: danalbert

Subscribers: srhines, christof, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D69929
2019-11-18 12:19:58 -08:00
Eric Fiselier f82dba0192 Rename __is_foo_iterator traits to reflect their Cpp17 nature.
With the upcoming introduction of iterator concepts in ranges,
the meaning of "__is_contiguous_iterator" changes drastically.

Currently we intend it to mean "does it have this iterator category",
but it could now also mean "does it meet the requirements of this
concept", and these can be different.
2019-11-18 01:49:32 -05:00
Eric Fiselier 6624fcba43 [libc++] Add _ITER_CONCEPT and _ITER_TRAITS implementations from C++20
These traits are currently unused because we don't implement ranges.
However, their addition is part of ongoing work to allow libc++
to optimize on user-provided contiguous iterators.
2019-11-16 20:26:35 -05:00
Eric Fiselier 45d048c204 [libc++] Add C++20 contiguous_iterator_tag.
This work is part of an ongoing effort to allow libc++ to
optimize user provided contiguous iterators.
2019-11-16 20:14:44 -05:00
Eric Fiselier 0068c59139 [libc++] Rename __to_raw_pointer to __to_address.
This function has the same behavior as the now-standand std::to_address.
Re-using the name makes the behavior more clear, and in the future it
will allow us to correctly get the raw pointer for user provided pointer
types.
2019-11-16 17:16:09 -05:00
Marek Kurdej 8e34be2f25 [libc++] [chrono] Fix year_month_weekday::ok() implementation.
Reviewers: ldionne, EricWF, mclow.lists

Reviewed By: mclow.lists

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D70282
2019-11-15 18:48:45 +01:00
Ilya Tokar 767eadd782 [libcxx] use __builtin_isnan in std::isnan.
Summary: This allows std::isnan to be fully inlined, instead of generating calls.

Reviewers: EricWF

Reviewed By: EricWF

Subscribers: christof, ldionne

Differential Revision: https://reviews.llvm.org/D69806
2019-11-15 12:29:18 -05:00
Louis Dionne 1466335cf4 [libc++][P1872] span should have size_type, not index_type.
Thanks to Marek Kurdej for the patch.

Differential Revision: https://reviews.llvm.org/D70206
2019-11-14 09:07:05 -05:00
Louis Dionne 8b77a3a0f4 [libc++] [P1612] Add missing feature-test macro __cpp_lib_endian.
Thanks to Marek Kurdej for the patch.

Differential Revision: https://reviews.llvm.org/D70221
2019-11-14 08:55:19 -05:00
Michael Park eb8710cb93
[libc++][P0980] Marked member functions move/copy/assign of char_traits constexpr.
Reviewers: ldionne, EricWF, mclow.lists

Reviewed By: ldionne

Subscribers: christof, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D68840
2019-11-11 09:49:48 -08:00
Louis Dionne 48b7068bec [libc++] Mark __call_once_proxy as hidden and internal
We effectively never want to export that function, which is an
implementation detail of libc++. This was previously tried in
603715c66b and then reverted in 8335dd314f because it caused
linker warnings. These linker warnings should go away now that we
use internal_linkage instead of always_inline to implement per-TU
insulation.
2019-11-11 10:27:48 -05:00
Mark de Wever 27c4eaac8c [libc++] Validate the entire regex is consumed
This change would have warned about the bug found in D62451.
No unit tests since the exception should never throw.

Differential Revision: https://reviews.llvm.org/D62452
2019-11-09 17:01:37 +01:00
Louis Dionne 0ec6a4882e [libc++] Fix potential OOB in poisson_distribution
See details in the original Chromium bug report:
    https://bugs.chromium.org/p/chromium/issues/detail?id=994957
2019-11-07 13:29:40 +00:00
Louis Dionne 83901cbe5e [libc++] Fixed copy/copy_n/copy_backward for compilers that do not support is_constant_evaluated.
Differential Revision: https://reviews.llvm.org/D69940
2019-11-07 12:39:10 +00:00
Louis Dionne 13c90a5716 [libc++][P0202] Marked algorithms copy/copy_n/copy_if/copy_backward constexpr
Thanks to Michael Park for the patch.

Differential Revision: https://reviews.llvm.org/D68837
2019-11-06 12:02:41 +00:00
Jorg Brown 586952f4ce Optimize std::midpoint for integers
Same idea as the current algorithm, that is, add (half of the difference between a and b) to a.

But we use a different technique for computing the difference: we compute b - a into a pair of integers that are named "sign_bit" and "diff". We have to use a pair because subtracting two 32-bit integers produces a 33-bit result.

Computing half of that is a simple matter of shifting diff right by 1, and adding sign_bit shifted left by 31. llvm knows how to do that with one instruction: shld.

The only tricky part is that if the difference is odd and negative, then shifting it by one isn't the same as dividing it by two - shifting a negative one produces a negative one, for example. So there's one more adjustment: if the sign bit and the low bit of diff are one, we add one.

For a demonstration of the codegen difference, see https://godbolt.org/z/7ar3K9 , which also has a built-in test.

Differential Revision: https://reviews.llvm.org/D69459
2019-11-04 19:00:23 -08:00
Louis Dionne adadc665f8 [libc++] Add test and remove workaround for PR13592
PR13592 was caused by a problem in how to compiler implemented the
__is_convertible_to intrinsic. That problem, reported as PR13591,
was fixed back in 2012. We don't support such old versions of Clang
anyway, so we don't need the library workaround that had been added
to solve PR13592 (while waiting for the compiler fix).
2019-10-30 15:52:11 -07:00
David Blaikie e658b3eb97 PR43764: Qualify a couple of calls to forward_as_tuple to be ADL-resilient. 2019-10-28 18:04:41 -07:00
--global a062856bcf [NFC] Comment endif to test commit access 2019-10-28 09:19:08 -07:00
Louis Dionne 6b77ebdc91 [NFC] Strip trailing whitespace from libc++ 2019-10-23 11:19:19 -07:00
Casey Carter 689ce81059
[libc++][NFC] Remove excess trailing newlines from most files
Testing git commit access.
2019-10-23 08:08:57 -07:00
Zoe Carver 40c47680eb [libcxx] Remove shared_ptr::make_shared
Summary: This patch removes `shared_ptr::make_shared` as it is not part of the standard. This patch also adds __create_with_cntrl_block, which is a help function that can be used in std::allocate_shared and std::make_shared. This is the third patch (out of 4) from D66178.

    Reviewers: EricWF, mclow.lists, ldionne

    Subscribers: christof, dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D68805

llvm-svn: 375504
2019-10-22 15:16:49 +00:00
Louis Dionne 3292facc0a [NFC] Fix typos in CMake comment
llvm-svn: 375469
2019-10-21 23:38:32 +00:00
Dimitry Andric d5367db95c Refine check for `_LIBCPP_C_HAS_NO_GETS` on FreeBSD
Summary:
In D67316 we added `_LIBCPP_C_HAS_NO_GETS` to signal that the C library
does not provide `gets()`, and added a test for FreeBSD 13 or higher,
using the compiler-defined `__FreeBSD__` macro.

Unfortunately this did not work that well for FreeBSD's own CI process,
since the gcc compilers used for some architectures define `__FreeBSD__`
to match the build host, not the target.

Instead, we should use the `__FreeBSD_version` macro from the userland
header `<osreldate.h>`, which is more fine-grained.  See also
<https://reviews.freebsd.org/D22034>.

Reviewers: EricWF, mclow.lists, emaste, ldionne

Reviewed By: emaste, ldionne

Subscribers: dexonsmith, bsdjhb, krytarowski, christof, ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D69174

llvm-svn: 375340
2019-10-19 10:59:23 +00:00
Richard Smith a9727033fb P1152R4: Fix deprecation warnings in libc++ testsuite and in uses of is_invocable that would internally conjure up a deprecated function type.
Summary: The implementation of P1152R4 in Clang has resulted in some deprecation warnings appearing in the libc++ and libc++abi test suite. Fix or suppress these warnings.

Reviewers: mclow.lists, EricWF

Subscribers: christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D68879

llvm-svn: 375307
2019-10-19 00:06:00 +00:00
Eric Fiselier 78153b3a97 Optimize operator=(const basic_string&) for tail call.
Patch by Martijn Vels (mvels@google.com)
Reviewed as https://reviews.llvm.org/D68276

This is a non trivial win for externally templated assignment operator.

x86 without tail call (current libc++)

0000000000000000 <std::string::operator=(std::string const&)>:
   0:   55                      push   %rbp
   1:   48 89 e5                mov    %rsp,%rbp
   4:   53                      push   %rbx
   5:   50                      push   %rax
   6:   48 89 fb                mov    %rdi,%rbx
   9:   48 39 f7                cmp    %rsi,%rdi
   c:   74 17                   je     25 <std::string::operator=(std::string const&)+0x25>
   e:   0f b6 56 17             movzbl 0x17(%rsi),%edx
  12:   84 d2                   test   %dl,%dl
  14:   79 07                   jns    1d <std::string::operator=(std::string const&)+0x1d>
  16:   48 8b 56 08             mov    0x8(%rsi),%rdx
  1a:   48 8b 36                mov    (%rsi),%rsi
  1d:   48 89 df                mov    %rbx,%rdi
  20:   e8 00 00 00 00          callq  25 <std::string::operator=(std::string const&)+0x25>
  25:   48 89 d8                mov    %rbx,%rax
  28:   48 83 c4 08             add    $0x8,%rsp
  2c:   5b                      pop    %rbx
  2d:   5d                      pop    %rbp
  2e:   c3                      retq

After:

0000000000000000 <std::string::operator=(std::string const&)>:
   0:   48 39 f7                cmp    %rsi,%rdi
   3:   74 14                   je     19 <std::string::operator=(std::string const&)+0x19>
   5:   0f b6 56 17             movzbl 0x17(%rsi),%edx
   9:   84 d2                   test   %dl,%dl
   b:   79 07                   jns    14 <std::string::operator=(std::string const&)+0x14>
   d:   48 8b 56 08             mov    0x8(%rsi),%rdx
  11:   48 8b 36                mov    (%rsi),%rsi
  14:   e9 00 00 00 00          jmpq   19 <std::string::operator=(std::string const&)+0x19>
  19:   48 89 f8                mov    %rdi,%rax
  1c:   c3                      retq

Benchmark (pending per https://reviews.llvm.org/D67667)

```
BM_StringAssignStr_Empty_Opaque                     6.23ns ± 0%             5.19ns ± 0%  -16.70%          (p=0.016 n=5+4)
BM_StringAssignStr_Empty_Transparent                5.86ns ± 0%             5.14ns ± 0%  -12.24%          (p=0.008 n=5+5)
BM_StringAssignStr_Small_Opaque                     8.79ns ± 1%             7.69ns ± 0%  -12.53%          (p=0.008 n=5+5)
BM_StringAssignStr_Small_Transparent                9.44ns ± 0%             8.00ns ± 0%  -15.26%          (p=0.008 n=5+5)
BM_StringAssignStr_Large_Opaque                     25.2ns ± 0%             24.3ns ± 0%   -3.50%          (p=0.008 n=5+5)
BM_StringAssignStr_Large_Transparent                23.6ns ± 0%             22.5ns ± 0%   -4.76%          (p=0.008 n=5+5)
BM_StringAssignStr_Huge_Opaque                       319ns ± 5%              317ns ± 5%     ~             (p=0.690 n=5+5)
BM_StringAssignStr_Huge_Transparent                  319ns ± 5%              317ns ± 5%     ~             (p=0.421 n=5+5)
BM_StringAssignAsciiz_Empty_Opaque                  7.41ns ± 0%             7.77ns ± 0%   +4.89%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Empty_Transparent             7.54ns ± 3%             7.30ns ± 0%   -3.24%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Small_Opaque                  9.87ns ± 0%            10.24ns ± 1%   +3.76%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Small_Transparent             10.4ns ± 1%              9.8ns ± 2%   -5.78%          (p=0.008 n=5+5)
BM_StringAssignAsciiz_Large_Opaque                  30.1ns ± 0%             30.1ns ± 0%     ~             (p=0.167 n=5+5)
BM_StringAssignAsciiz_Large_Transparent             27.1ns ± 0%             27.4ns ± 0%   +0.92%          (p=0.016 n=4+5)
BM_StringAssignAsciiz_Huge_Opaque                    383ns ± 4%              382ns ± 4%     ~             (p=0.548 n=5+5)
BM_StringAssignAsciiz_Huge_Transparent               375ns ± 0%              380ns ± 0%   +1.37%          (p=0.029 n=4+4)
BM_StringAssignAsciizMix_Opaque                     14.0ns ± 0%             14.0ns ± 0%     ~             (p=0.881 n=5+5)
BM_StringAssignAsciizMix_Transparent                13.7ns ± 1%             13.8ns ± 0%     ~             (p=0.056 n=5+5)
```

llvm-svn: 374137
2019-10-09 03:07:02 +00:00
Zoe Carver a9d43b55c7 [libc++] Remove C++03 variadics in shared_ptr (v2)
Summary: In my last patch (D67675) I forgot a few variadics. This patch removes the remaining make_shared and allocate_shared C++03 variadics.

    Reviewers: ldionne, EricWF, mclow.lists

    Subscribers: christof, dexonsmith, libcxx-commits

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D68000

llvm-svn: 373971
2019-10-07 21:41:15 +00:00
Louis Dionne 371ea70bb7 [libc++] Harden usage of static_assert against C++03
In C++03, we emulate static_assert with a macro, and we must parenthesize
multiple arguments.

llvm-svn: 373328
2019-10-01 12:12:21 +00:00
Eric Fiselier c8ad8686ac Refactor default constructor SFINAE in pair and tuple.
Refactor the  recent implicit default constructor changes to match the
existing SFINAE style.

llvm-svn: 373263
2019-09-30 20:55:30 +00:00
Louis Dionne 59e26308e6 [libc++] Take 2: Implement LWG 3158
Summary:
LWG 3158 marks the allocator_arg_t constructor of std::tuple as
conditionnally explicit based on whether the default constructors
of the tuple's members are explicitly default constructible.

This was previously committed as r372778 and reverted in r372832 due to
the commit breaking LLVM's build in C++14 mode. This issue has now been
addressed.

Reviewers: mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65232

llvm-svn: 373092
2019-09-27 15:06:52 +00:00
Louis Dionne e16f2cb678 [libc++] Take 2: Implement LWG 2510
Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.

This was previously committed as r372777 and reverted in r372832 due to
the commit breaking LLVM's build in C++14 mode. This issue has now been
addressed.

Reviewers: mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65161

llvm-svn: 372983
2019-09-26 14:51:10 +00:00
David Zarzycki a068601510 [libcxx] Do not implicitly #include assert.h
Users should only get the assert() macros if they explicitly include
them.

Found after switching from the GNU C++ stdlib to the LLVM C++ stdlib.

llvm-svn: 372963
2019-09-26 11:12:29 +00:00
Eric Fiselier af4a29af01 Add forward declaration of operator<< in <string_view> as required.
This declaration was previously missing despite appearing in the
synopsis. Users are still required to include <ostream> to get the
definition of the streaming operator.

llvm-svn: 372909
2019-09-25 18:56:54 +00:00
Marshall Clow e3f89a989a Add a missing default parameter to regex::assign. This is LWG3296; reviewed as https://reviews.llvm.org/D67944
llvm-svn: 372896
2019-09-25 16:40:30 +00:00
Ilya Biryukov a3d337a9a7 Revert r372777: [libc++] Implement LWG 2510 and its follow-ups
This also reverts:
 - r372778: [libc++] Implement LWG 3158
 - r372782: [libc++] Try fixing tests that fail on GCC 5 and older
 - r372787: Purge mentions of GCC 4 from the test suite

Reason: the change breaks compilation of LLVM with libc++, for details see
http://lists.llvm.org/pipermail/libcxx-dev/2019-September/000599.html

llvm-svn: 372832
2019-09-25 09:10:38 +00:00
Zoe Carver 4278a9e6b5 [libc++] Remove C++03 variadics in shared_ptr
Summary: As suggested by @ldionne in D66178, this patch removes C++03 variadics //only//. Following patches will apply more updates.

    Reviewers: ldionne, EricWF, mclow.lists

    Subscribers: christof, dexonsmith, libcxx-commits, ldionne

    Tags: #libc

    Differential Revision: https://reviews.llvm.org/D67675

llvm-svn: 372780
2019-09-24 20:55:54 +00:00
Louis Dionne e9e1c88ed9 [libc++] Implement LWG 3158
Summary:
LWG 3158 marks the allocator_arg_t constructor of std::tuple as
conditionnally explicit based on whether the default constructors
of the tuple's members are explicitly default constructible.

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65232

llvm-svn: 372778
2019-09-24 20:22:34 +00:00
Louis Dionne 95411dd426 [libc++] Implement LWG 2510
Summary:
LWG2510 makes tag types like allocator_arg_t explicitly default
constructible instead of implicitly default constructible. It also
makes the constructors for std::pair and std::tuple conditionally
explicit based on the explicit-ness of the default constructibility
for the pair/tuple's elements.

Reviewers: mclow.lists, EricWF

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D65161

llvm-svn: 372777
2019-09-24 20:18:54 +00:00
Marshall Clow ab8f77a73e Revert "Extension: Mark the default constructor of chrono::duration as conditionally noexcept"; this breaks the gcc5 bot for C++11
This reverts commit c8ca15c95c4c0d6d1356500d5fe49a319ea4ca01.

llvm-svn: 372546
2019-09-23 06:16:41 +00:00
Marshall Clow d8ac51ab8f Extension: Mark the default constructor of chrono::duration as conditionally noexcept
llvm-svn: 372539
2019-09-23 04:16:48 +00:00
Dan Albert 85e26f56cb Revert "Revert "Implement std::condition_variable via pthread_cond_clockwait() where available""
With the fix for non-Linux.

This reverts commit c1c519d2f1.

llvm-svn: 372242
2019-09-18 18:13:32 +00:00
Dan Albert c1c519d2f1 Revert "Implement std::condition_variable via pthread_cond_clockwait() where available"
This reverts commit 5e37d7f9ff.

llvm-svn: 372034
2019-09-16 21:20:32 +00:00
Dan Albert a7e9059967 Open fstream files in O_CLOEXEC mode when possible.
Reviewers: EricWF, mclow.lists, ldionne

Reviewed By: ldionne

Subscribers: smeenai, dexonsmith, christof, ldionne, libcxx-commits

Tags: #libc

Differential Revision: https://reviews.llvm.org/D59839

llvm-svn: 372027
2019-09-16 19:26:41 +00:00
Dan Albert 5e37d7f9ff Implement std::condition_variable via pthread_cond_clockwait() where available
std::condition_variable is currently implemented via
pthread_cond_timedwait() on systems that use pthread. This is
problematic, since that function waits by default on CLOCK_REALTIME
and libc++ does not provide any mechanism to change from this
default.

Due to this, regardless of if condition_variable::wait_until() is
called with a chrono::system_clock or chrono::steady_clock parameter,
condition_variable::wait_until() will wait using CLOCK_REALTIME. This
is not accurate to the C++ standard as calling
condition_variable::wait_until() with a chrono::steady_clock parameter
should use CLOCK_MONOTONIC.

This is particularly problematic because CLOCK_REALTIME is a bad
choice as it is subject to discontinuous time adjustments, that may
cause condition_variable::wait_until() to immediately timeout or wait
indefinitely.

This change fixes this issue with a new POSIX function,
pthread_cond_clockwait() proposed on
http://austingroupbugs.net/view.php?id=1216. The new function is
similar to pthread_cond_timedwait() with the addition of a clock
parameter that allows it to wait using either CLOCK_REALTIME or
CLOCK_MONOTONIC, thus allowing condition_variable::wait_until() to
wait using CLOCK_REALTIME for chrono::system_clock and CLOCK_MONOTONIC
for chrono::steady_clock.

pthread_cond_clockwait() is implemented in glibc (2.30 and later) and
Android's bionic (Android API version 30 and later).

This change additionally makes wait_for() and wait_until() with clocks
other than chrono::system_clock use CLOCK_MONOTONIC.<Paste>

llvm-svn: 372016
2019-09-16 17:57:48 +00:00
Eric Fiselier 6bc1236d39 Add debug check for null pointers passed to <string_view>
llvm-svn: 371925
2019-09-14 19:55:28 +00:00
Eric Fiselier cb9216b908 Fix C++03 build failures due to >>
llvm-svn: 371894
2019-09-13 20:30:45 +00:00