Commit Graph

158 Commits

Author SHA1 Message Date
Arthur O'Dwyer 14098cf6c0 [libc++] [P0202] constexpr set_union, set_difference, set_symmetric_difference, merge
These had been waiting on the ability to use `std::copy` from
constexpr code (which in turn had been waiting on the ability to
use `is_constant_evaluated()` to switch between `memmove` and non-`memmove`
implementations of `std::copy`). That work landed a while ago,
so these algorithms can all be constexpr in C++20 now.

Simultaneously, update the tests for the set algorithms.

- Use an element type with "equivalent but not identical" values.
- The custom-comparator tests now pass something different from `operator<`.
- Make the constexpr coverage match the non-constexpr coverage.

Differential Revision: https://reviews.llvm.org/D92255
2020-12-04 17:53:54 -05:00
Brett Gutstein 297c839e2d [libc++] fix std::sort(T**, T**)
previously, invocations of std::sort(T**, T**) casted the arguments to
(size_t *). this breaks sorting on systems for which pointers don't fit
in a size_t. change the cast to (uintptr_t *) and add a test.

Differential Revision: https://reviews.llvm.org/D92190
2020-12-04 16:05:21 -05:00
Arthur O'Dwyer d586f92c94 [libc++] Consistently replace `std::` qualification with `_VSTD::` or nothing. NFCI.
I used a lot of `git grep` to find places where `std::` was being used
outside of comments and assert-messages. There were three outcomes:

- Qualified function calls, e.g. `std::move` becomes `_VSTD::move`.
    This is the most common case.

- Typenames that don't need qualification, e.g. `std::allocator` becomes `allocator`.
    Leaving these as `_VSTD::allocator` would also be fine, but I decided
    that removing the qualification is more consistent with existing practice.

- Names that specifically need un-versioned `std::` qualification,
    or that I wasn't sure about. For example, I didn't touch any code in
    <atomic>, <math.h>, <new>, or any ext/ or experimental/ headers;
    and I didn't touch any instances of `std::type_info`.

In some deduction guides, we were accidentally using `class Alloc = typename std::allocator<T>`,
despite `std::allocator<T>`'s type-ness not being template-dependent.
Because `std::allocator` is a qualified name, this did parse as we intended;
but what we meant was simply `class Alloc = allocator<T>`.

Differential Revision: https://reviews.llvm.org/D92250
2020-12-01 22:13:39 -05:00
Bruce Mitchener 527a7fdfbd [libc++] Replace several uses of 0 by nullptr
Differential Revision: https://reviews.llvm.org/D43159
2020-11-27 10:00:21 -05:00
Arthur O'Dwyer ee95c7020c [libc++] Remove _LIBCPP_CONSTEXPR_AFTER_CXX17_WITH_IS_CONSTANT_EVALUATED.
Zoe Carver says: "We decided that libc++ only supports C++20 constexpr algorithms
when `is_constant_evaluated` is also supported. Here's a link to the discussion."
https://reviews.llvm.org/D65721#inline-735682

Remove _LIBCPP_HAS_NO_BUILTIN_IS_CONSTANT_EVALUATED from tests, too.
See Louis's 5911e6a885 if needed to fix bots.
I've applied `UNSUPPORTED: clang-8` preemptively to the altered tests;
I don't know for sure that this was needed, because no clang-8 buildbots
are triggered on pull requests.
2020-11-24 11:04:21 -05:00
zoecarver 3ed89b51da [Take 2] [libc++] Make rotate a constexpr.
This patch makes `std::rotate` a constexpr. In doing so, this patch also
updates the internal `__move` and `__move_backward` funtions to be
constexpr.

This patch was previously reverted in ed653184ac because it was missing
some UNSUPPORTED markup for older compilers. This commit adds it.

Differential Revision: https://reviews.llvm.org/D65721
2020-09-14 18:14:46 -04:00
zoecarver ed653184ac Revert "[libc++] Make rotate a constexpr."
This reverts commit 1ec02efee9.
2020-09-14 14:53:17 -07:00
Nicholas-Baron b552a30283 [libc++] Finish implementing P0202R3
cppreference lists the support for this paper as partial.
I found 4 functions which the paper marks as `constexpr`,
but did not use the appropriate macro.

Differential Revision: https://reviews.llvm.org/D84275
2020-09-14 16:58:49 -04:00
zoecarver 1ec02efee9 [libc++] Make rotate a constexpr.
This patch makes `std::rotate` a constexpr. In doing so, this patch also
updates the internal `__move` and `__move_backward` funtions to be
constexpr.

Reviewed By: ldionne

Differential Revision: https://reviews.llvm.org/D65721
2020-09-14 13:56:48 -07:00
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
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
Marshall Clow 4f41779cca Add a missing _VSTD:: before a call to merge. Fixes PR43034. Checked the rest of 'algorithm' looking for unqualified calls. Didn't find any.
llvm-svn: 369463
2019-08-20 22:23:35 +00:00
Marshall Clow 7fa6865392 Fix a couple of unguarded operator, calls in algorithm. Fixes PR#43063. Updated all the heap tests to check this.
llvm-svn: 369448
2019-08-20 21:31:51 +00:00
Louis Dionne 956892433f [pstl][libc++] Provide uglified header names for interface headers
For the few (currently four) headers that make up the PSTL's interface
to other Standard Libraries, provide a stable uglified header file that
can be included by those Standard Libraries.

We can then more easily change the internal organization of the PSTL
without having to change the integration with Standard Libraries.

llvm-svn: 368088
2019-08-06 21:11:24 +00:00
Louis Dionne 0a06eb911b [libc++] Take 2: Integrate the PSTL into libc++
Summary:
This commit allows specifying LIBCXX_ENABLE_PARALLEL_ALGORITHMS when
configuring libc++ in CMake. When that option is enabled, libc++ will
assume that the PSTL can be found somewhere on the CMake module path,
and it will provide the C++17 parallel algorithms based on the PSTL
(that is assumed to be available).

The commit also adds support for running the PSTL tests as part of
the libc++ test suite.

The first attempt to commit this failed because it exposed a bug in the
tests for modules. Now that this has been fixed, it should be safe to
commit this.

Reviewers: EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits, mclow.lists, EricWF

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60480

llvm-svn: 367903
2019-08-05 18:29:14 +00:00
Louis Dionne a3c83b7511 Revert "[libc++] Integrate the PSTL into libc++"
This reverts r366593, which caused unforeseen breakage on the build bots.
I'm reverting until the problems have been figured out and fixed.

llvm-svn: 366603
2019-07-19 18:52:46 +00:00
Louis Dionne 910323e667 [libc++] Integrate the PSTL into libc++
Summary:
This commit allows specifying LIBCXX_ENABLE_PARALLEL_ALGORITHMS when
configuring libc++ in CMake. When that option is enabled, libc++ will
assume that the PSTL can be found somewhere on the CMake module path,
and it will provide the C++17 parallel algorithms based on the PSTL
(that is assumed to be available).

The commit also adds support for running the PSTL tests as part of
the libc++ test suite.

Reviewers: rodgert, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, libcxx-commits, mclow.lists, EricWF

Tags: #libc

Differential Revision: https://reviews.llvm.org/D60480

llvm-svn: 366593
2019-07-19 17:02:42 +00:00
Marshall Clow f3b851f0b8 Reorganize the 'bit' header to make most of the facilities available for internal use pre-C++20. NFC for external users
llvm-svn: 365854
2019-07-12 01:01:55 +00:00
Eric Fiselier 000f25a37e Make move and forward work in C++03.
These functions are key to allowing the use of rvalues and variadics
in C++03 mode. Everything works the same as in C++11, except for one
tangentially related case:

struct T {
  T(T &&) = default;
};

In C++11, T has a deleted copy constructor. But in C++03 Clang gives
it both a move and a copy constructor. This seems reasonable enough
given the extensions it's using.

The other changes in this patch were the minimal set required
to keep the tests passing after the move/forward change. Most notably
the removal of the `__rv<unique_ptr>` hack that was present
in an attempt to make unique_ptr move only without language support.

llvm-svn: 364063
2019-06-21 15:20:55 +00:00
Thomas Anderson 6ab51de08e [libc++] Make __debug_less::operator() constexpr
This is a followup to [1] which added a new `__debug_less::operator()` overload.
[2] added `_LIBCPP_CONSTEXPR_AFTER_CXX17` to the original
`__debug_less::operator()` between the time of writing [1] and landing it.  This
change adds `_LIBCPP_CONSTEXPR_AFTER_CXX17` to the new overload too.

[1] https://reviews.llvm.org/rL358423
[2] https://reviews.llvm.org/rL358252

Differential Revision: https://reviews.llvm.org/D60724

llvm-svn: 358725
2019-04-19 00:52:54 +00:00
Thomas Anderson 3c3ccc0049 [libc++] Fix build failure with _LIBCPP_DEBUG=0 when iterators return values instead of references
There are many STL algorithms (such as lexicographical_compare) that compare
values pointed to by iterators like so:
    __comp(*it1, *it2);
	
When building with `_LIBCPP_DEBUG=0`, comparators are wrapped in `__debug_less`
which does some additional validation.  But `__debug_less::operator()` takes
non-const references, so if the type of `*it1` is int, not int&, then the build
will fail.

This change adds a `const&` overload for `operator()` to fix the build.

Differential Revision: https://reviews.llvm.org/D60592

llvm-svn: 358423
2019-04-15 17:02:15 +00:00
Eric Fiselier aa1cad1591 Cleanup how debug comparators are created in <algorithm>
Instead of having an `#if` block in every algorithm using a debug
comparator, this patch introduces the __comp_ref_type trait that
selects __debug_less in debug mode and _Comp& otherwise.

This patch should have no observable functionality change.

llvm-svn: 358252
2019-04-12 05:18:19 +00:00
Nico Weber 1362d7ef88 libcxx: Add _LIBCPP_NODISCARD_EXT to 38 more functions
This builds on the work done in r342808 and adds _LIBCPP_NODISCARD_EXT
to 37 more functions, namely:

adjacent_find, all_of, any_of, binary_search, clamp, count_if, count,
equal_range, equal, find_end, find_first_not_of, find_first_of, find_if,
find, includes, is_heap_until, is_heap, is_partitioned, is_permutation,
is_sorted_until, is_sorted, lexicographical_compare, lower_bound,
max_element, max, min_element, min, minmax_element, minmax, mismatch,
none_of, remove_if, remove, search_n, search, unique, upper_bound

The motivation here is that we noticed that find_if is nodiscard with
Visual Studio's standard library, and we deemed that useful
(https://crbug.com/948122).
https://devblogs.microsoft.com/cppblog/c17-progress-in-vs-2017-15-5-and-15-6/
says "Our criteria for emitting the warning are: discarding the return
value is a guaranteed leak [...], discarding the return value is
near-guaranteed to be incorrect (e.g. remove()/remove_if()/unique()), or
the function is essentially a pure observer (e.g. vector::empty() and
std::is_sorted())." so I went through algorithm and tried to apply these
criteria.

Some of these, like vector::empty() are already nodiscard per C++
standard and didn't need changing.

I didn't (yet?) go over std::string::find* methods which should probably
have _LIBCPP_NODISCARD_EXT too (but not as part of this change).

Differential Revision: https://reviews.llvm.org/D60145

llvm-svn: 357619
2019-04-03 18:13:08 +00:00
Eric Fiselier 6e4ec6022f Fix PR41017 - Build failure with _LIBCPP_DEBUG=0 and non-const-ref
comparator for std::sort()

Our debug comparator assumed that the comparator it wraps would always
accepts the values by const ref. This isn't required by the standard.

This patch makes our __debug_less comparator forward the constness.

llvm-svn: 355752
2019-03-08 22:58:59 +00:00
Marshall Clow c8879ab2fd Add a specialization for '__unwrap_iter' to handle const interators. This enables the 'memmove' optimization for std::copy, etc.
llvm-svn: 353311
2019-02-06 16:10:25 +00:00
Marshall Clow 5a8525e0b6 D14686: 'Protect against overloaded comma in random_shuffle and improve tests' I had to cut back on the tests with this, because they were not C++03 friendly. Thanks to gribozavr for the patch
llvm-svn: 352087
2019-01-24 19:20:19 +00:00
Chandler Carruth 57b08b0944 Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351648
2019-01-19 10:56:40 +00:00
Louis Dionne 04695a7539 [libcxx] Speeding up partition_point/lower_bound/upper_bound
This is a re-application of r345525, which had been reverted by fear of
a regression.

Reviewed as https://reviews.llvm.org/D53994.
Thanks to Denis Yaroshevskiy for the patch.

llvm-svn: 349358
2018-12-17 16:04:39 +00:00
Louis Dionne 835140a427 [libcxx] Make sure we can build with -fvisibility=hidden on Linux
Summary:
This commit marks a few functions as hidden and removes them from the ABI list
on Linux such that libc++ can be built with -fvisibility=hidden. The functions
marked as hidden by this patch were exported from the shared object only
because they were implicitly instantiated function templates. It is safe
to stop exporting those symbols from the shared object because nobody could
actually depend on them: implicit instantiations are not taken from shared
objects.

The symbols removed in this commit are basically the same that had been
removed in https://reviews.llvm.org/D53868, but that patch had to be reverted
because it broke the build (because the functions were not marked as hidden
like this patch does).

Reviewers: EricWF, mclow.lists

Subscribers: christof, jkorous, dexonsmith, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54639

llvm-svn: 347395
2018-11-21 16:24:46 +00:00
Louis Dionne e0a724ef9c Revert "Bug 39129: Speeding up partition_point/lower_bound/upper_bound/ by using unsigned division by 2 when possible."
This reverts r345525. I'm reverting because that patch apparently caused
a regression on certain platforms (see https://reviews.llvm.org/D53994).
Since we don't fully understand the reasons for the regression, I'm
reverting until we can provide a fix we understand.

llvm-svn: 345893
2018-11-01 21:24:32 +00:00
Eric Fiselier 8c40d81d4f Bug 39129: Speeding up partition_point/lower_bound/upper_bound/ by using unsigned division by 2 when possible.
Patch by Denis Yaroshevskiy (denis.yaroshevskij@gmail.com)

The rational and measurements can be found in the bug description: https://bugs.llvm.org/show_bug.cgi?id=39129

Reviewed as https://reviews.llvm.org/D52697

llvm-svn: 345525
2018-10-29 19:25:02 +00:00
Eric Fiselier e503a1c3b8 Fix PR39458 _LIBCPP_DEBUG breaks heterogeneous compare.
The types/comparators passed to std::upper_bound and std::lower_bound
are not required to provided to provide an operator</comp(...) which
accepts the arguments in reverse order. Nor are the ranges required
to have a strict weak ordering.

However, in debug mode we attempted to check the result of a comparison
with the arguments reversed, which may not compiler.

This patch removes the use of the debug comparator for upper_bound
and lower_bound.

equal_range et al still use debug comparators when they call
__upper_bound and __lower_bound.

See llvm.org/PR39458

llvm-svn: 345434
2018-10-26 22:54:46 +00:00
Marshall Clow 2dd5335204 Do the math in uniform_int_distribution::operator() as unsigned to prevent UB when overflowing. Also add a UBSAN notification that we're ffine with unsigned overflow. This fixes PR#32617. Thanks to Vincent & Christoph for their help with this issue.
llvm-svn: 343996
2018-10-08 20:20:34 +00:00
Louis Dionne ea5cd3b476 [libc++] Add deprecated attributes to many deprecated components
Summary:
These deprecation warnings are opt-in: they are only enabled when the
_LIBCXX_DEPRECATION_WARNINGS macro is defined, which is not the case
by default. Note that this is a first step in the right direction, but
I wasn't able to get an exhaustive list of all deprecated components
per standard, so there's certainly stuff that's missing. The list of
components this commit marks as deprecated is:

in C++11:
- auto_ptr, auto_ptr_ref
- binder1st, binder2nd, bind1st(), bind2nd()
- pointer_to_unary_function, pointer_to_binary_function, ptr_fun()
- mem_fun_t, mem_fun1_t, const_mem_fun_t, const_mem_fun1_t, mem_fun()
- mem_fun_ref_t, mem_fun1_ref_t, const_mem_fun_ref_t, const_mem_fun1_ref_t, mem_fun_ref()

in C++14:
- random_shuffle()

in C++17:
- unary_negate, binary_negate, not1(), not2()

<rdar://problem/18168350>

Reviewers: mclow.lists, EricWF

Subscribers: christof, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D48912

llvm-svn: 342843
2018-09-23 18:35:00 +00:00
Marshall Clow f56972e224 Implement the infrastructure for feature-test macros. Very few actual feature test macros, though. Reviewed as: https://reviews.llvm.org/D51955
llvm-svn: 342073
2018-09-12 19:41:40 +00:00
Marshall Clow e9cc545129 Fix PR# 38900 - don't call swap inside of random_shuffle when we'd be swapping an element with itself
llvm-svn: 341975
2018-09-11 18:33:45 +00:00
Eric Fiselier a60d7fac09 Add diagnostics for min/max algorithms when a InputIterator is used.
These algorithms require a ForwardIterator or better. Ensure
we diagnose the contract violation at compile time instead of
of silently doing the wrong thing.

Further algorithms will be audited in upcoming patches.

llvm-svn: 340426
2018-08-22 17:47:13 +00:00
Marshall Clow e02ee4f013 Recommit r339943 - Establish the <bit> header. NFC yet. Reviewed as https://reviews.llvm.org/D50815 - with a fix for the sanitizer bots
llvm-svn: 340045
2018-08-17 16:07:48 +00:00
Vitaly Buka 0d52fce74d Revert "Establish the <bit> header. NFC yet. Reviewed as https://reviews.llvm.org/D50815"
Breaks build on sanitizer bots.

This reverts commit r339943.

llvm-svn: 339971
2018-08-16 23:57:16 +00:00
Marshall Clow 496bb865c6 Establish the <bit> header. NFC yet. Reviewed as https://reviews.llvm.org/D50815
llvm-svn: 339943
2018-08-16 21:35:38 +00:00
Marshall Clow d8098f9799 Mark __equal_to 's operations as constexpr.
llvm-svn: 337087
2018-07-14 04:15:19 +00:00
Marshall Clow 9cad502555 Make internal class __wrap_iter constexpr when not using libc++'s debugging mode. Introduce a new macro _LIBCPP_CONSTEXPR_IF_NODEBUG to mark this.
llvm-svn: 337019
2018-07-13 16:35:26 +00:00
Marshall Clow f951fc399f Fix misleading indentation; replace a couple of NULLs with nullptr. Resolves https://reviews.llvm.org/D42945 ; thanks to Bruce Mitchener for the patch.
llvm-svn: 324378
2018-02-06 18:58:05 +00:00
Peter Collingbourne 939b16233b Fix the BinaryPredicate form of std::is_permutation to not rely on operator==
According to [1], forms 2 and 4 of std::is_permutation should use the passed in
binary predicate to compare elements. operator== should only be used for forms
1 and 3 which do not take a binary predicate.

This CL fixes forms 2 and 4 which relied on operator== for some comparisons.

[1] http://en.cppreference.com/w/cpp/algorithm/is_permutation

Patch by Thomas Anderson!

Differential Revision: https://reviews.llvm.org/D42518

llvm-svn: 323563
2018-01-26 21:23:27 +00:00
Marshall Clow 8da1a487ae Last batch of P0202 constexpr additions: includes/set_intersection/exchange
llvm-svn: 323159
2018-01-22 23:10:40 +00:00
Marshall Clow e8ea8296fc Another batch of P0202 constepr algirithms. remove/remove_if/remove_copy/remove_copy_if/reverse_copy, and tests (commented out) for rotate_copy, because that depends on std::copy
llvm-svn: 323152
2018-01-22 21:43:04 +00:00
Marshall Clow 1b9a4ffd6b Still more P0202 constexpr-ifying. This batch is: for_each/for_each_n/lexicographical_compare
llvm-svn: 323147
2018-01-22 20:44:33 +00:00
Marshall Clow 4bfb9313c1 More P0202 constexpr work. This commit adds fill/fill_n/generate/generate_n/unique/unique_copy. I removed a specialization of fill_n that recognized when we were dealing with raw pointers and 1 byte trivially-assignable types and did a memset, because the compiler will do that optimization for us.
llvm-svn: 323050
2018-01-20 20:14:32 +00:00
Marshall Clow 12c7423ff9 More P0202 constexpr-ifying in <algorithm>. This commit handles replace/replace_if/replace_copy/replace_copy_if.
llvm-svn: 322975
2018-01-19 18:07:29 +00:00