Commit Graph

2698 Commits

Author SHA1 Message Date
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