Commit Graph

184 Commits

Author SHA1 Message Date
Louis Dionne cb793e1a36 [libc++][NFCI] Remove uses of _LIBCPP_INLINE_VAR
All supported compilers provide support for inline variables in C++17 now.
Also, as a fly-by fix, replace some uses of _LIBCPP_CONSTEXPR by just
constexpr.

The only exception in this patch is `std::ignore`, which is provided
prior to C++17. Since it is defined in an anonymous namespace, it always
has internal linkage anyway, so using an inline variable there doesn't
provide any benefit. Instead, `inline` was removed entirely on `std::ignore`.

Differential Revision: https://reviews.llvm.org/D110243
2021-09-22 16:03:00 -04:00
Louis Dionne 64184b4af0 [libc++][NFC] Remove useless _LIBCPP_PUSH_MACROS
Only files that actually use min/max are required to do this dance.

Differential Revision: https://reviews.llvm.org/D108778
2021-08-27 12:41:55 -04:00
Christopher Di Bella 050b064f15 [libcxx][functional][modular] splices <functional> into modular headers
Differential Revision: https://reviews.llvm.org/D104942
2021-07-01 14:01:49 -04:00
Louis Dionne d03aa7d6b6 [libc++] NFCI: Remove __functional/search.h
The __search helper function was once split into __functional for circular
dependency reasons, however this is not an issue anymore now that we have
finer grained headers.
2021-06-29 11:40:47 -04:00
Christopher Di Bella 6adbc83ee9 [libcxx][modularisation] moves <utility> content out of <type_traits>
Moves:

* `std::move`, `std::forward`, `std::declval`, and `std::swap` into
  `__utility/${FUNCTION_NAME}`.
* `std::swap_ranges` and `std::iter_swap` into
  `__algorithm/${FUNCTION_NAME}`

Differential Revision: https://reviews.llvm.org/D103734
2021-06-24 17:57:29 +00:00
Louis Dionne 134723edd5 [libcxx] Move all algorithms into their own headers
This is a fairly mechanical change, it just moves each algorithm into
its own header. This is intended to be a NFC.

This commit re-applies 7ed7d4ccb8, which was reverted in 692d7166f7
because the Modules build got broken. The modules build has now been
fixed, so we're re-committing this.

Differential Revision: https://reviews.llvm.org/D103583

Attribution note
----------------
I'm only committing this. This commit is a mix of D103583, D103330 and
D104171 authored by:

Co-authored-by: Christopher Di Bella <cjdb@google.com>
Co-authored-by: zoecarver <z.zoelec2@gmail.com>
2021-06-19 07:49:06 -04:00
Petr Hosek 692d7166f7 Revert "[libcxx][gardening] Move all algorithms into their own headers."
This reverts commit 7ed7d4ccb8 as it
uncovered a Clang bug PR50592.
2021-06-07 17:15:20 -07:00
zoecarver 7ed7d4ccb8 [libcxx][gardening] Move all algorithms into their own headers.
This is a fairly mechanical change, it just moves each algorithm into its own header. This is a NFC.

Note: during this change, I burned down all the includes, so this follows "include only and exactly what you use."

Differential Revision: https://reviews.llvm.org/D103583
2021-06-04 09:37:12 -07:00
Arthur O'Dwyer 6491d99e33 [libc++] Remove more unnecessary _VSTD:: from type names. NFCI.
Differential Revision: https://reviews.llvm.org/D102181
2021-05-11 12:23:55 -04:00
Arthur O'Dwyer 0b8da5fa59 [libc++] s/std::size_t/size_t/g. NFCI. 2021-05-11 12:23:55 -04:00
Arthur O'Dwyer ab3fcc5065 [libc++] s/_VSTD::declval/declval/g. NFCI. 2021-05-11 12:23:55 -04:00
Arthur O'Dwyer e6972024c8 [libc++] Fix some typos and remove unused macros. NFCI.
Reviewed as part of https://reviews.llvm.org/D100737
2021-04-22 12:02:22 -04:00
Martin Storsjö 948dd664c3 [libcxx] Fix the type attribute for a couple templates
Use `_LIBCPP_TEMPLATE_VIS` instead of `_LIBCPP_TYPE_VIS` for a template
class.

This fixes the nodiscard_extensions.pass.cpp and a couple
func.search.default test cases when built in MSVC/DLL configurations.

Differential Revision: https://reviews.llvm.org/D99932
2021-04-06 19:54:34 +03:00
Marek Kurdej 5c703f0fd8 [libc++] Build and test with -Wundef warning. NFC.
This will avoid typos like `_LIBCPP_STD_VERS` (<future>) or using `#if TEST_STD_VER > 17` without including "test_macros.h".

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D99515
2021-04-01 08:32:56 +02:00
Arthur O'Dwyer d430330788 [libc++] Update and normalize the "all the headers" tests.
Some C++20 headers weren't added properly to all three of these
test files. Add them, and take the time to normalize the formatting
so that

    diff <(grep '#include' foo.cpp) <(grep '#include' bar.cpp)

shows no diffs (except that `no_assert_include` deliberately
excludes `<cassert>`).

- Add macro guards to <{barrier,latch,semaphore}>.
- Add macro guards to <experimental/simd>.
- Remove an include of <cassert> from <semaphore>.
- Instead, include <cassert> in the semaphore tests.

Differential Revision: https://reviews.llvm.org/D92525
2020-12-03 15:01:38 -05:00
zoecarver 0a20660c8f [libcxx] Resolve LWG 2724 protected -> private.
Fixes LWG issue 2724: "The protected virtual member functions of memory_resource should be private."

Differential Revision: https://reviews.llvm.org/D66615
2020-11-23 14:27:22 -08:00
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
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
Louis Dionne 776acf225b [libcxx] Slightly improved policy for handling experimental features
Summary:
Following the discussion on the libcxx-dev mailing list
(http://lists.llvm.org/pipermail/libcxx-dev/2019-May/000358.html),
this implements the new policy for handling experimental features and
their deprecation. We basically add a deprecation warning for
std::experimental::filesystem, and we remove a bunch of <experimental/*>
headers that were now empty.

Reviewers: mclow.lists, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits, jfb

Tags: #libc

Differential Revision: https://reviews.llvm.org/D62428

llvm-svn: 363072
2019-06-11 14:48:40 +00:00
Marshall Clow 39084db328 Implement LWG 2960: nonesuch is insufficiently useless
llvm-svn: 359526
2019-04-30 00:54:38 +00:00
Eric Fiselier c3d6a929fd Fix visibility for coroutine types on Windows
llvm-svn: 358551
2019-04-17 04:31:46 +00:00
Brian Gesiak b66754a29e Revert "[coroutines] Add std::experimental::task<T> type"
This revision is causing build and test failures, such as
http://lab.llvm.org:8011/builders/libcxx-libcxxabi-libunwind-armv8-linux/builds/648/steps/test.libcxx/logs/stdio,
so I'll revert it.

llvm-svn: 357023
2019-03-26 19:50:46 +00:00
Brian Gesiak 57839425aa [coroutines] Add std::experimental::task<T> type
Summary:
Adds the coroutine `std::experimental::task<T>` type described in proposal P1056R0.
See https://wg21.link/P1056R0.

This implementation allows customization of the allocator used to allocate the
coroutine frame by passing std::allocator_arg as the first argument, followed by
the allocator to use.

This supports co_awaiting the same task multiple times. The second and
subsequent times it returns a reference to the already-computed value.

This diff also adds some implementations of other utilities that have potential for
standardization as helpers within the test/... area:
- `sync_wait(awaitable)` - See P1171R0
- `manual_reset_event`

Move the definition of the __aligned_allocation_size helper function
from <experimental/memory_resource> to <experimental/__memory>
so it can be more widely used without pulling in memory_resource.

Outstanding work:
- Use C++14 keywords directly rather than macro versions
  eg. use `noexcept` instead of `_NOEXCEPT`).
- Add support for overaligned coroutine frames.
  This may need wording in the Coroutines TS to support passing the extra `std::align_val_t`.
- Eliminate use of `if constexpr` if we want it to compile under C++14.

Patch by @lewissbaker (Lewis Baker).

llvm-svn: 357010
2019-03-26 17:46:06 +00:00
Louis Dionne 1be935f418 [libc++] Remove visibility-related warnings with Clang 8
The attributes were placed incorrectly -- they need to be after the
"struct" keyword, not before.

llvm-svn: 355006
2019-02-27 17:33:25 +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
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

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: 351636
2019-01-19 08:50:56 +00:00
Eric Fiselier d108bf85b0 Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`.
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See  llvm.org/PR39713

This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.

This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.

I think we should commit this change immediately, and decide what we want to do about the ABI afterwards. 

Reviewers: ldionne, EricWF

Reviewed By: ldionne, EricWF

Subscribers: jyknight, christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54814

llvm-svn: 351289
2019-01-16 01:51:12 +00:00
Eric Fiselier b168a7c660 Fix PR39749 - Headers containing just #error harm __has_include.
This patch changes <experimental/foo> to use #warning instead of
is harmful to common feature detection idioms.

We should also consider only emitting the warning when __DEPRECATED is
defined, like we do in the <ext/foo> headers. Users may want to specify
"-Werror=-W#warnings" while still ignoring the libc++ warnings.

llvm-svn: 350485
2019-01-06 00:37:31 +00:00
Eric Fiselier 9d25ada420 Revert "Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`. "
This reverts commit 087f065cb0c7463f521a62599884493aaee2ea12.

The tests were failing on 32 bit builds, and I don't have time
to clean them up right now. I'll recommit tomorrow with fixed tests.

llvm-svn: 347816
2018-11-28 22:24:19 +00:00
Eric Fiselier 8a486dac25 Move internal usages of `alignof`/`__alignof` to use `_LIBCPP_ALIGNOF`.
Summary:
Starting in Clang 8.0 and GCC 8.0, `alignof` and `__alignof` return different values in same cases. Specifically `alignof` and `_Alignof` return the minimum alignment for a type, where as `__alignof` returns the preferred alignment. libc++ currently uses `__alignof` but means to use `alignof`. See  llvm.org/PR39713

This patch introduces the macro `_LIBCPP_ALIGNOF` so we can control which spelling gets used.

This patch does not introduce any ABI guard to provide the old behavior with newer compilers. However, if we decide that is needed, this patch makes it trivial to implement.

I think we should commit this change immediately, and decide what we want to do about the ABI afterwards. 

Reviewers: ldionne, EricWF

Reviewed By: EricWF

Subscribers: christof, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54814

llvm-svn: 347787
2018-11-28 18:16:02 +00:00
Louis Dionne 9a494eacba [libcxx] Remove dynarray
Summary:
std::dynarray had been proposed for C++14, but it was pulled out from C++14
and there are no plans to standardize it anymore.

Reviewers: mclow.lists, EricWF

Subscribers: mgorny, christof, jkorous, dexonsmith, arphaman, libcxx-commits

Differential Revision: https://reviews.llvm.org/D54801

llvm-svn: 347783
2018-11-28 18:02:00 +00:00
Eric Fiselier f25b75b91b Implement sized deallocation for std::allocator and friends.
Summary:
C++14 sized deallocation is disabled by default due to ABI concerns. However, when a user manually enables it then libc++ should take advantage of it since sized deallocation can provide a significant performance win depending on the underlying malloc implementation. (Note that libc++'s definitions of sized delete don't do anything special yet, but users are free to provide their own).

This patch updates __libcpp_deallocate to selectively call sized operator delete when it's available. `__libcpp_deallocate_unsized` should be used when the size of the allocation is unknown.

On Apple this patch makes no attempt to determine if the sized operator delete is unavailable, only that the language feature is enabled. This could cause a compile error when using `std::allocator`, but the same compile error would occur whenever the user calls `new`, so I don't think it's a problem.

Reviewers: ldionne, mclow.lists

Reviewed By: ldionne

Subscribers: rsmith, ckennelly, libcxx-commits, christof

Differential Revision: https://reviews.llvm.org/D53120

llvm-svn: 345281
2018-10-25 17:21:30 +00:00
Eric Christopher 9ecdb5a711 Revert "Fix use of __libcpp_deallocate in dynarray"
This reverts commit r345234 as it depended on the sized deallocation commit.

llvm-svn: 345240
2018-10-25 06:43:56 +00:00
Eric Fiselier 46493ac9b5 Fix use of __libcpp_deallocate in dynarray
llvm-svn: 345234
2018-10-25 02:36:31 +00:00
Tim Shen 38cd7de5ac Re-apply "[libcxx] implement <simd> ABI for Clang/GCC vector extension, constructors, copy_from and copy_to."
...with proper guarding #ifdefs for unsupported C++11.

llvm-svn: 338318
2018-07-30 22:27:38 +00:00
Tim Shen 6f33ea4ef6 Revert "[libcxx] implement <simd> ABI for Clang/GCC vector extension, constructors, copy_from and copy_to."
This reverts commit r338309.

llvm-svn: 338316
2018-07-30 22:21:22 +00:00
Tim Shen 47ad09b339 [libcxx] implement <simd> ABI for Clang/GCC vector extension, constructors, copy_from and copy_to.
Summary:
This patch adds a new macro _LIBCPP_HAS_NO_VECTOR_EXTENSION for detecting
whether a vector extension (\_\_attribute\_\_((vector_size(num_bytes)))) is
available.

On the top of that, this patch implements the following API:
* all constructors
* operator[]
* copy_from
* copy_to

It also defines simd_abi::native to use vector extension, if available.
In GCC and Clang, certain values with vector extension are passed by registers,
instead of memory.

Based on D41148.

Reviewers: mclow.lists, EricWF

Subscribers: cfe-commits, MaskRay, lichray, sanjoy

Differential Revision: https://reviews.llvm.org/D41376

llvm-svn: 338309
2018-07-30 21:23:13 +00:00
Eric Fiselier 998a5c8831 Implement <filesystem>
This patch implements the <filesystem> header and uses that
to provide <experimental/filesystem>.

Unlike other standard headers, the symbols needed for <filesystem>
have not yet been placed in libc++.so. Instead they live in the
new libc++fs.a library. Users of filesystem are required to link this
library. (Also note that libc++experimental no longer contains the
definition of <experimental/filesystem>, which now requires linking libc++fs).

The reason for keeping <filesystem> out of the dylib for now is that
it's still somewhat experimental, and the possibility of requiring an
ABI breaking change is very real. In the future the symbols will likely
be moved into the dylib, or the dylib will be made to link libc++fs automagically).

Note that moving the symbols out of libc++experimental may break user builds
until they update to -lc++fs. This should be OK, because the experimental
library provides no stability guarantees. However, I plan on looking into
ways we can force libc++experimental to automagically link libc++fs.

In order to use a single implementation and set of tests for <filesystem>, it
has been placed in a special `__fs` namespace. This namespace is inline in
C++17 onward, but not before that. As such implementation is available
in C++11 onward, but no filesystem namespace is present "directly", and
as such name conflicts shouldn't occur in C++11 or C++14.

llvm-svn: 338093
2018-07-27 03:07:09 +00:00
Eric Fiselier c55ac1055a [libc++] Use __int128_t to represent file_time_type.
Summary:
The ``file_time_type`` time point is used to represent the write times for files.
Its job is to act as part of a C++ wrapper for less ideal system interfaces. The
underlying filesystem uses the ``timespec`` struct for the same purpose.

However, the initial implementation of ``file_time_type`` could not represent
either the range or resolution of ``timespec``, making it unsuitable. Fixing
this requires an implementation which uses more than 64 bits to store the
time point.

I primarily considered two solutions: Using ``__int128_t`` and using a
arithmetic emulation of ``timespec``. Each has its pros and cons, and both
come with more than one complication.

However, after a lot of consideration, I decided on using `__int128_t`. This patch implements that change.

Please see the [FileTimeType Design Document](http://libcxx.llvm.org/docs/DesignDocs/FileTimeType.html) for more information.

Reviewers: mclow.lists, ldionne, joerg, arthur.j.odwyer, EricWF

Reviewed By: EricWF

Subscribers: christof, K-ballo, cfe-commits, BillyONeal

Differential Revision: https://reviews.llvm.org/D49774

llvm-svn: 337960
2018-07-25 20:51:49 +00:00
Eric Fiselier 5baf73c354 Make <experimental/filesystem> explicitly require C++11.
Previously the <experimental/filesystem> didn't guard its
contents in any dialect. However, the implementation implicitly
requires at least C++11, and the tests have always been marked
unsupported in C++03. This patch puts a header guard around the
contents to avoid exposing them before C++11.

Additionally, it replaces all of the usages of _NOEXCEPT or
_LIBCPP_CONSTEXPR with the keyword directly, since we can
expect the compiler to implement those by now.

llvm-svn: 337884
2018-07-25 03:41:31 +00:00
Eric Fiselier 52ec6a206f Ensure path::iterator and PathParser share the same enumeration values.
To avoid exposing implementation details, path::iterator and PathParser
both implicitly used the same set of values to represent the state,
but they were defined twice. This could have lead to a mismatch
occuring.

This patch moves all of the parser state values into the filesystem
header and changes PathParser to use those value to avoid this.

llvm-svn: 337883
2018-07-25 03:31:48 +00:00
Eric Fiselier f96de02960 Recommit "Use possibly cached directory entry values when performing recursive directory iteration."
The initial patch didn't correctly handle systems when the dirent struct
didn't provide the d_type member. Specifically it set the cache to the incorrect state,
and claimed it was partially populated.

The updated version of this change correctly handles setting up the
cache when the file type is not known (aka file_type::none).

llvm-svn: 337765
2018-07-23 22:40:41 +00:00
Eric Fiselier 9158bfd32e Implement filesystem_error::what() and improve reporting.
This patch implements the `what()` for filesystem errors. The message
includes the 'what_arg', any paths that were specified, and the
error code message.

Additionally this patch refactors how errors are created, making it easier
to report them correctly.

llvm-svn: 337664
2018-07-23 02:00:52 +00:00
Eric Fiselier 3bf90e7811 Fix two test failures in <experimental/filesystem>
First, <experimental/filesystem> didn't correctly guard
against min/max macros. This adds the proper push/pop macro guards.

Second, an internal time helper had been renamed but the test for
it hadn't been updated. This patch updates those tests.

llvm-svn: 337520
2018-07-20 01:51:48 +00:00
Eric Fiselier 41cdcbeedd Use _LIBCPP_UNREACHABLE to convince GCC that non-void functions actually always return
llvm-svn: 337519
2018-07-20 01:44:33 +00:00
Eric Fiselier c16998649e [libc++] Implement Directory Entry Caching -- Sort of.
Summary:
This patch implements directory_entry caching *almost* as specified in P0317r1. However, I explicitly chose to deviate from the standard as I'll explain below.

The approach I decided to take is a fully caching one. When `refresh()` is called, the cache is populated by calls to `stat` and `lstat` as needed.
During directory iteration the cache is only populated with the `file_type` as reported by `readdir`.
The cache can be in the following states:

* `_Empty`: There is nothing in the cache (likely due to an error)
* `_IterSymlink`: Created by directory iteration when we walk onto a symlink only the symlink file type is known.
* `_IterNonSymlink`: Created by directory iteration when we walk onto a non-symlink. Both the regular file type and symlink file type are known.
* `_RefreshSymlink` and `_RefreshNonSymlink`: A full cache created by `refresh()`.  This case includes dead symlinks.
* `_RefreshSymlinkUnresolved`: A partial cache created by refresh when we fail to resolve the file pointed to by a symlink (likely due to permissions). Symlink attributes are cached, but attributes about the linked entity are not.

As mentioned, this implementation purposefully deviates from the standard. According to some readings of the specification, and the Windows filesystem implementation, the constructors and modifiers which don't pass an `error_code` must throw when the `directory_entry` points to a entity which doesn't exist. or when attribute resolution fails for another reason. 

@BillyONeal  has proposed a more reasonable set of requirements, where modifiers other than refresh ignore errors. This is the behavior libc++ currently implements, with the expectation some form of the new language will be accepted into the standard.

Some additional semantics which differ from the Windows implementation:

1. `refresh` will not throw when the entry doesn't exist. In this case we can still meet the functions specification, so we don't treat it as an error.
2. We don't clear the path name when a constructor fails via refresh (this will hopefully be changed in the standard as well).

It should be noted that libstdc++'s current implementation has the same behavior as libc++, except for point (2).

If the changes to the specification don't get accepted, we'll be able to make the changes later.

[1] http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0317r1.html

Reviewers: mclow.lists, gromer, ldionne, aaron.ballman

Subscribers: BillyONeal, christof, cfe-commits

Differential Revision: https://reviews.llvm.org/D49530

llvm-svn: 337516
2018-07-20 01:22:32 +00:00
Louis Dionne dc7200b486 [libc++] Take 2: Replace uses of _LIBCPP_ALWAYS_INLINE by _LIBCPP_INLINE_VISIBILITY
Summary:
We never actually mean to always inline a function -- all the uses of
the macro I could find are actually attempts to control the visibility
of symbols. This is better described by _LIBCPP_INLINE_VISIBILITY, which
is actually always defined the same.

This change is orthogonal to the decision of what we're actually going
to do with _LIBCPP_INLINE_VISIBILITY -- it just simplifies things by
having one canonical way of doing things.

Note that this commit had originally been applied in r336369 and then
reverted in r336382 because of unforeseen problems. Both of these problems
have now been fixed.

Reviewers: EricWF, mclow.lists

Subscribers: christof, dexonsmith, erikvanderpoel

Differential Revision: https://reviews.llvm.org/D48892

llvm-svn: 336866
2018-07-11 23:14:33 +00:00
Louis Dionne cf3ae38405 [libc++] Declare noop_coroutine() with _LIBCPP_INLINE_VISIBILITY
Summary:
It was defined with the right visibility, but declared without any visibility.
This function was left out of a prior revision that did the same to several
functions in <compare> (r336665) because the compiler I used didn't support
coroutines. This reinforces the need for automated checks -- there might
still be several cases of this throughout the library.

Reviewers: EricWF

Subscribers: modocache, christof, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D49145

llvm-svn: 336709
2018-07-10 17:38:30 +00:00
Louis Dionne 195a499d63 Revert "[libc++] Replace uses of _LIBCPP_ALWAYS_INLINE by _LIBCPP_INLINE_VISIBILITY"
This reverts commit r336369. The commit had two problems:
1. __pbump was marked as _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY instead of
   _LIBCPP_INLINE_VISIBILITY, which lead to two symbols being added in the
   dylib and the check-cxx-abilist failing.

2. The LLDB tests started failing because they undefine
   `_LIBCPP_INLINE_VISIBILITY`. I need to figure out why they do that and
   fix the tests before we can go forward with this change.

llvm-svn: 336382
2018-07-05 18:41:50 +00:00