Commit Graph

4469 Commits

Author SHA1 Message Date
Arthur O'Dwyer 6842f52a0b [libc++] [test] Flatten the directory structure a bit. NFC.
Differential Revision: https://reviews.llvm.org/D116198
2021-12-23 14:56:23 -05:00
Mark de Wever dfb20d4d19 [libc++][format] Improve ABI stability.
During the review of D115991 @vitaut pointed out the enum shouldn't
depend on whether or not _LIBCPP_HAS_NO_INT128 is defined. The current
implementation lets the enum's ABI depend on this configuration option
without a good cause.

Reviewed By: ldionne, #libc

Differential Revision: https://reviews.llvm.org/D116120
2021-12-23 17:37:12 +01:00
Nikolas Klauser 1d50cf98b5 [libc++] IWYU in <filesystem> tests
Add headers in `<filesystem>` tests that were transitively included
through `<filesystem>`

Reviewed as part of D116146
2021-12-23 12:03:36 +01:00
Nikolas Klauser fcc0964ed4 Revert "[libc++] Remove unused headers from <filesystem>"
This reverts commit 352945dd36.
2021-12-23 11:55:38 +01:00
Nikolas Klauser 352945dd36 [libc++] Remove unused headers from <filesystem>
Remove unused headers from `<filesystem>`

Spies: libcxx-commits

Differential Revision: https://reviews.llvm.org/D116146
2021-12-23 02:07:47 +01:00
Arthur O'Dwyer cb8a0b0797 [libc++] [ranges] Introduce _LIBCPP_AUTO_CAST(x) for auto(x).
Clang is gaining `auto(x)` support in D113393; sadly there
seems to be no feature-test macro for it. Zhihao is opening
a core issue for that macro.

Use `_LIBCPP_AUTO_CAST` where C++20 specifies we should use `auto(x)`;
stop using `__decay_copy(x)` in those places.
In fact, remove `__decay_copy` entirely. As of C++20, it's purely
a paper specification tool signifying "Return just `x`, but it was
perfect-forwarded, so we understand you're going to have to call
its move-constructor sometimes." I believe there's no reason we'd
ever need to do its operation explicitly in code.

This heisenbugs away a test failure on MinGW; see D112214.

Differential Revision: https://reviews.llvm.org/D115686
2021-12-22 12:29:42 -05:00
Arthur O'Dwyer 8ad364ad21 [libc++] [ranges] Remove the static_assert from ranges::begin and ranges::end.
As discussed with ldionne. The problem with this static_assert
is that it makes ranges::begin a pitfall for anyone ever to use
inside a constraint or decltype. Many Ranges things, such as ranges::size,
are specified as "Does X if X is well-formed, or else Y if Y is well-formed,
or else `ranges::end(t) - ranges::begin(t)` if that is well-formed, or else..."
And if there's a static_assert hidden inside `ranges::begin(t)`, then you get
a hard error as soon as you ask the question -- even if the answer would have
been "no, that's not well-formed"!

Constraining on `requires { t + 0; }` or `requires { t + N; }` is verboten
because of https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103700 . For ranges::begin,
we can just decay to a pointer even in the incomplete-type case. For ranges::end,
we can safely constrain on `sizeof(*t)`. Yes, this means that an array of incomplete
type has a `ranges::begin` but no `ranges::end`... just like an unbounded array of
complete type. This is a valid manifestation of IFNDR.

All of the new libcxx/test/std/ cases are mandatory behavior, as far as I'm aware.
Tests for the IFNDR cases in ranges::begin and ranges::end remain in `libcxx/test/libcxx/`.
The similar tests for ranges::empty and ranges::data were simply wrong, AFAIK.

Differential Revision: https://reviews.llvm.org/D115838
2021-12-22 10:33:17 -05:00
Martin Storsjö 7176799a7e [libc++] Add from-scratch testing configs for Windows
The paths to the compiler and to the python executable may need to
be quoted (if they're installed into e.g. C:\Program Files).

All testing commands that are executed expect a gcc compatible command
line interface, while clang-cl uses different command line options.
In the original testing config, if the chosen compiler was clang-cl, it
was replaced with clang++ by looking for such an executable in the path.

For the new from-scratch test configs, I instead chose to add
"--driver-mode=g++" to flags - invoking "clang-cl --driver-mode=g++"
has the same effect as invoking "clang++", without needing to run any
heuristics for picking a different compiler executable.

Differential Revision: https://reviews.llvm.org/D111202
2021-12-22 15:16:58 +02:00
Martin Storsjö 516882a8f2 [libcxx] [test] Prepare the ctime.timespec test for mingw CI env upgrades
The test is currently marked XFAIL for mingw environments, but latest
mingw-w64 got support for timespec_get:
e62a0a987c

The CI environment will probably be upgraded to a state where this
test is passing only after 14.x is branched in the llvm-project monorepo.

If we'd just go from having an XFAIL to no marking at all (when CI is
passing), we'd have to update both main and 14.x branches in sync
exactly when the CI runners are updated to a newer version.

Instead, mark the test as temporarily unsupported (so it doesn't
cause failed builds when the CI environment is updated); after the
CI environments are upgraded to such a state, we can remove the
UNSUPPORTED marking to start requiring it to pass on the main branch,
without needing to synchronize that change to anything else.

Differential Revision: https://reviews.llvm.org/D116132
2021-12-22 15:14:55 +02:00
Nikolas Klauser 7056250f51 [libc++][NFC] Granularize <filesystem>
Granularize the `<filesystem>` header

Reviewed By: Quuxplusone, ldionne, #libc

Spies: libcxx-commits, mgorny

Differential Revision: https://reviews.llvm.org/D115578
2021-12-22 02:31:17 +01:00
Arthur O'Dwyer 1fe897dffd [libc++] [test] Simplify some ranges tests.
Eliminate a bogus operator== overload.
Also, check more intermediate steps in the logic we're checking here.
Some of this simplification is possible only now that we've implemented
more of <ranges>.

Differential Revision: https://reviews.llvm.org/D116002
2021-12-21 20:16:35 -05:00
Martin Storsjö d67b25e7f6 [libcxx] [test] Extend test for bash for executor-has-no-bash
If %{exec} sets "--env PATH=single-dir", the directory containing
bash and related shell utils is omitted from the path, which means
that most shell scripts would fail.

(Setting PATH is needed for DLL builds on Windows; PATH fills the same
role as e.g. LD_LIBRARY_PATH on Linux.)

This condition is missed in the current test, because the executor
run.py first resolves the executable to run using the original path,
then invokes that executable with an environment with a restricted
path. Thus the executor is able to run bash, but that bash is then
unable to run further shell commands (other than bash builtins).

Extend the test from "bash --version" to "bash -c 'bash --version'".
This correctly identifies the executor-has-no-bash condition in the
current Windows CI configs, allowing removing 6 cases of
LIBCXX-WINDOWS-FIXME.

Another longterm fix would be to extend run.py with an option like
"--env-prepend PATH=dir", to allow keeping the current path while
adding a directory to it.

Differential Revision: https://reviews.llvm.org/D116117
2021-12-22 00:43:29 +02:00
Martin Storsjö c1a14a5c3e [libcxx] Use LIBCXX_EXECUTOR in new test configs
This allows cross-testing (by setting LIBCXX_EXECUTOR to point
to ssh.py) without making an entirely new test config file.

Implicitly, this also fixes quoting of the python executable name
(which is quoted in test/CMakeLists.txt).

Differential Revision: https://reviews.llvm.org/D115398
2021-12-22 00:43:28 +02:00
Martin Storsjö 008849d7a5 [libcxx] [test] Don't rerun supportsVerify for each individual test
We can't just memoize _supportsVerify in place in format.py, as it
previously was executed in each of the individual processes.

Instead use hasCompileFlag() and add a feature flag for it instead,
which can be used both by tests (that already have such a flag,
locally for one set of tests) and for the testing framework itself.

By using hasCompileFlag(), this also implicitly fixes two other issues:
Previously, _supportsVerify called subprocess.call() directly, which can
interpret command line quoting differently than lit.TestRunner.

(In particular, TestRunner handles arguments quoted by a single quote,
while launching Windows processes with subprocess.call() only supports
double quotes. This allows using shlex.quote(), which uses single quotes,
everywhere - as all commands now go through TestRunner. This should make
41d7909368 redundant.)

Secondly, the old _supportsVerify method didn't include %{flags) or
%{compile_flags}.

Differential Revision: https://reviews.llvm.org/D116010
2021-12-21 19:40:30 +02:00
Louis Dionne d5b3cb0711 [libc++][NFC] Fix links to https://llvm.org/PR20183 in the tests 2021-12-21 10:34:08 -05:00
Joe Loser 8dbc7745e5
[libcxx][test] Verify customization point object properties
Add test for various customization point object properties as defined by
the Standard. Test various CPOs from `<ranges>`, `<iterator>`,
`<concepts>`, etc.

The test is mostly from https://reviews.llvm.org/D107036 and split up
into this.

Differential Revision: https://reviews.llvm.org/D115588
2021-12-21 10:12:19 -05:00
Raul Tambre 4e730aeb73 [libcxx] Add deprecation notices to macros deprecated in P0883R2
When P0883R2 was initially implemented in D103769 #pragma clang deprecated didn't exist yet.
We also forgot to cleanup usages in libc++ itself.

This takes care of both.

Differential Revision: https://reviews.llvm.org/D115995
2021-12-20 20:30:00 +02:00
Louis Dionne 37e6bd8bc8 [libc++] Add a helper class to write code with the strong exception guarantee
__transaction is a helper class that allows rolling back code in case an
exception is thrown. The main goal is to reduce the clutter when code
needs to be guarded with `#if _LIBCPP_NO_EXCEPTIONS`.

Differential Revision: https://reviews.llvm.org/D115730
2021-12-20 11:17:29 -05:00
Konstantin Varlamov 754ea6fd4d [libc++][ranges] Implement `uninitialized_value_construct{,_n}` and `uninitialized_fill{,_n}`.
Also:
- refactor out `__voidify`;
- use the `destroy` algorithm internally;
- refactor out helper classes used in tests for `uninitialized_*`
  algorithms.

Differential Revision: https://reviews.llvm.org/D115626
2021-12-20 00:24:27 -08:00
Konstantin Boyarinov ff94bd1bc9 [libcxx][test][NFC] noexcept tests for std::array
Minor change - add tests that std::array methods (data, (c/r)begin,
(c/r)end) are noexcept

Reviewed By: ldionne, rarutyun, #libc

Differential Revision: https://reviews.llvm.org/D115717
2021-12-18 16:06:56 +03:00
Konstantin Varlamov f195fd915e [libc++][ranges][NFC] Remove extraneous cleanup checks.
There is no need to check the counters on `Counted` after destroying
elements in the range because these tests are not testing `destroy`.

Differential Revision: https://reviews.llvm.org/D115839
2021-12-16 14:47:59 -08:00
Arthur O'Dwyer 2a04decc4a [libc++] [test] Simplify sentinel_wrapper and sized_sentinel.
Remove `s.base()`; every test that wants to get the base of a "test sentinel"
should use the ADL `base(s)` from now on.

Differential Revision: https://reviews.llvm.org/D115766
2021-12-16 12:02:58 -05:00
Nikolas Klauser 148ef80f89 [libc++] Add GCC workaround in std::char_traits<char>::length()
GCC currently does not allow `__builtin_strlen()` during constant evaluation. This PR adds a workaround in `std::char_traits<char>::length()`

Reviewed By: Quuxplusone, ldionne, #libc, Mordante

Spies: Mordante, libcxx-commits

Differential Revision: https://reviews.llvm.org/D115795
2021-12-16 14:27:51 +01:00
Nikolas Klauser 17cfc57d14 [libc++] Implement P0798R8 (Monadic operations for std::optional)
Implement P0798R8

Reviewed By: #libc, ldionne, Quuxplusone

Spies: tcanens, Quuxplusone, ldionne, Wmbat, arichardson, Mordante, libcxx-commits

Differential Revision: https://reviews.llvm.org/D113408
2021-12-15 22:49:03 +01:00
Konstantin Varlamov 3f630cff65 [libc++][ranges] Implement ranges::uninitialized_default_construct{,_n}.
Defined in [`specialized.algorithms`](wg21.link/specialized.algorithms).

Also:
- refactor the existing non-range implementation so that most of it
  can be shared between the range-based and non-range-based algorithms;
- remove an existing test for the non-range version of
  `uninitialized_default_construct{,_n}` that likely triggered undefined
  behavior (it read the values of built-ins after default-initializing
  them, essentially reading uninitialized memory).

Reviewed By: #libc, Quuxplusone, ldionne

Differential Revision: https://reviews.llvm.org/D115315
2021-12-14 14:11:46 -08:00
Louis Dionne 87fe0709d4 [libc++] Allow detecting whether the executor supports Bash
A few tests in the test suite require support for Bash. For example,
tests that run a program and send data through stdin to it require some
way of piping the data in, and we use a Bash script for that.

However, some executors (e.g. an embedded systems simulator) do not
support Bash, so these tests will fail. This commit adds a Lit feature
that tries to detect whether Bash is available through conventional
means, and disables the tests that require it otherwise.

Differential Revision: https://reviews.llvm.org/D114612
2021-12-14 16:54:13 -05:00
Louis Dionne bf39e7dc6c [libc++] Fix wrongly non-inline basic_string::shrink_to_fit
As explained in https://stackoverflow.com/a/70339311/627587, the fact
that shrink_to_fit wasn't defined as inline lead to issues when explicitly
instantiating basic_string. While explicit instantiations are always
somewhat brittle, this one was clearly a bug on our end.

Differential Revision: https://reviews.llvm.org/D115656
2021-12-14 11:12:04 -05:00
Nikolas Klauser 3d510343c4 [libc++] Make ThrowingIterator constexpr
Make ThrowingIterator constexpr

Reviewed By: Quuxplusone, ldionne, #libc

Spies: libcxx-commits

Differential Revision: https://reviews.llvm.org/D115579
2021-12-14 01:13:21 +01:00
Arthur O'Dwyer 4dd901f4d3 [libc++] Fix the noexceptness of __decay_copy.
When `a` was an array type, `__decay_copy(a)` was incorrectly marking itself
noexcept(false), because it is false that `int[10]` is nothrow convertible to `int[10]`
(in fact it is not convertible at all).

We have no tests explicitly for `__decay_copy`, but the new ranges::begin
and ranges::end tests fail before this patch.

Differential Revision: https://reviews.llvm.org/D115658
2021-12-13 17:55:38 -05:00
Muiez Ahmed b8c12af9dd [SystemZ][z/OS] Fix handling of dirs with filesystem tests
The aim of this patch is to fix the post processing that is happening on the temporary test directories upon scope exit. In particular, ~scoped_test_env aims to chmod and remove the temporary directories; however,

bad symlinks are followed and we get "No such file or directory". FIX: use find as alternative to chmod and avoid -follow option.
Attempting to remove read-only files on z/OS prompts a message asking for confirmation. FIX: use the -f option to delete read-only files immediately without asking for confirmation.
Some libcxx tests such as libcxx/test/std/input.output/filesystems/cl ass.directory_entry/directory_entry.cons/path.pass.cpp set the dir permissions to none. In turn, recursively doing chmod (-R) does not set the file permissions needed to be able to remove the dir on z/OS only. FIX: use find as alternative to chmod -R, which does not run into this issue on z/OS.

Differential Revision: https://reviews.llvm.org/D108326
2021-12-13 11:02:23 -05:00
Mark de Wever abb5dd6e99 Microsoft's floating-point to_chars powered by Ryu and Ryu Printf
Microsoft would like to contribute its implementation of floating-point to_chars to libc++. This uses the impossibly fast Ryu and Ryu Printf algorithms invented by Ulf Adams at Google. Upstream repos: https://github.com/microsoft/STL and https://github.com/ulfjack/ryu .

Licensing notes: MSVC's STL is available under the Apache License v2.0 with LLVM Exception, intentionally chosen to match libc++. We've used Ryu under the Boost Software License.

This patch contains minor changes from Jorg Brown at Google, to adapt the code to libc++. He verified that it works in Google's Linux-based environment, but then I applied more changes on top of his, so any compiler errors are my fault. (I haven't tried to build and test libc++ yet.) Please tell me if we need to do anything else in order to follow https://llvm.org/docs/DeveloperPolicy.html#attribution-of-changes .

Notes:

* libc++'s integer charconv is unchanged (except for a small refactoring). MSVC's integer charconv hasn't been tuned for performance yet, so you're not missing anything.
* Floating-point from_chars isn't part of this patch because Jorg found that MSVC's implementation (derived from our CRT's strtod) was slower than Abseil's. If you're unable to use Abseil or another implementation due to licensing or technical considerations, Microsoft would be delighted if you used MSVC's from_chars (and you can just take it, or ask us to provide a patch like this). Ulf is also working on a novel algorithm for from_chars.
* This assumes that float is IEEE 32-bit, double is IEEE 64-bit, and long double is also IEEE 64-bit.
* I have added MSVC's charconv tests (the whole thing: integer/floating from_chars/to_chars), but haven't adapted them to libcxx's harness at all. (These tests will be available in the microsoft/STL repo soon.)
* Jorg added int128 codepaths. These were originally present in upstream Ryu, and I removed them from microsoft/STL purely for performance reasons (MSVC doesn't support int128; Clang on Windows does, but I found that x64 intrinsics were slightly faster).
* The implementation is split into 3 headers. In MSVC's STL, charconv contains only Microsoft-written code. xcharconv_ryu.h contains code derived from Ryu (with significant modifications and additions). xcharconv_ryu_tables.h contains Ryu's large lookup tables (they were sufficiently large to make editing inconvenient, hence the separate file). The xmeow.h convention is MSVC's for internal headers; you may wish to rename them.
* You should consider separately compiling the lookup tables (see https://github.com/microsoft/STL/issues/172 ) for compiler throughput and reduced object file size.
* See https://github.com/StephanTLavavej/llvm-project/commits/charconv for fine-grained history. (If necessary, I can perform some rebase surgery to show you what Jorg changed relative to the microsoft/STL repo; currently that's all fused into the first commit.)

Differential Revision: https://reviews.llvm.org/D70631
2021-12-12 16:34:50 +01:00
Konstantin Varlamov 805488358a [libc++][ranges] Add subsumption tests to `[special.mem.concepts]`.
Test that `nothrow-forward-iterator` subsumes `nothrow-input-iterator`,
`nothrow-forward-range` subsumes `nothrow-input-range`, and
`nothrow-sentinel-for` and `sentinel_for` subsume each other.

This is a follow-up to [D114761](https://reviews.llvm.org/D114761).

Differential Revision: https://reviews.llvm.org/D115422
2021-12-12 00:37:23 -08:00
Konstantin Boyarinov 82ff94a59c [libcxx][test][NFC] Extend testing for vector.cons
Extending std::vector tests in vector.cons module:

- std::vector::assign when source range is bigger than destination
  capacity
- construction of empty vector using copy ctor, initializer_list ctor and
  others

Reviewed By: ldionne, rarutyun, #libc

Differential Revision: https://reviews.llvm.org/D114954
2021-12-10 15:05:22 +03:00
Konstantin Boyarinov ab018330f3 [libcxx][test][NFC] Tests for set comparisons
Add tests for std::set and std::multiset comparisons that were missed by
D111738 and D112424.

Reviewed By: ldionne, rarutyun, #libc

Differential Revision: https://reviews.llvm.org/D115136
2021-12-10 14:51:24 +03:00
Joe Loser ec63930c06
[libc++][NFC] Remove test/support/tracked_value.h
No tests are using `libcxx/test/support/tracked_value.h`. So, remove it.

Differential Revision: https://reviews.llvm.org/D115411
2021-12-08 21:18:58 -05:00
Arthur O'Dwyer f638c4d6e4 [libc++] [test] Refactor range.prim/empty.pass.cpp.
No decrease in test coverage intended. The original goal here
was just to get rid of the global name `sentinel` so that we can
rename the `sentinel_wrapper` in "test_iterators.h" to `sentinel`;
but then I took a closer look at the offending tests and saw
that some of them probably weren't testing what they intended.

Also, add one `/*explicit*/` and one #if'ed out test indicating
bugs in the current ranges::empty (to be fixed by D115312 or
some equivalent patch).

Reviewed as part of D115272.
2021-12-08 16:41:02 -05:00
Arthur O'Dwyer c19d8f955a [libc++] [test] Use sized_sentinel<int*> in range.prim/ssize.pass.cpp.
Reviewed as part of D115272.
2021-12-08 16:41:02 -05:00
Arthur O'Dwyer 67c43d87cd [libc++] [test_iterators] Make all ADL base() functions into hidden friends. NFCI.
This follows up on my addition of base(cpp20_input_iterator) in D115177,
making all the ADL base() functions consistent.
Also align cpp20_input_iterator with the other test iterators' style.

Reviewed as part of D115272.
2021-12-08 16:41:01 -05:00
Louis Dionne a6e5563dfa [libc++][release] Do not force building the runtimes with -fPIC
There's a lot of history behind this, so here's a summary:

1. I stopped forcing -fPIC when building the runtimes in 30f305efe2,
   before the LLVM 9 release back in 2019.

2. Someone complained that libc++.a couldn't be used in shared libraries
   built without -fPIC (http://llvm.org/PR43604) since the LLVM 9 release.
   This had been caused by my removal of -fPIC when building libc++.a in (1).

3. I suggested two ways of fixing the issue, the first being to force
   -fPIC back unconditionally (http://llvm.org/D104328), and the second
   being to specify that option explicitly when building the LLVM release
   (http://llvm.org/D104327). We converged on the first solution.

4. I landed D104328, which forced building the runtimes with -fPIC.
   This was included in the LLVM 13.0 release.

5. People complained about that and requested that we be able to
   customize this setting (basically we should have done the second
   solution).

This patch makes it such that the LLVM release script will specifically
ask for building with -fPIC using CMAKE_POSITION_INDEPENDENT_CODE,
however by default the runtimes will not force that option onto users.

This patch has the unintended effect that Clang and the LLVM libraries
(not only the runtime ones like libc++) will also be built with -fPIC
in the release. It would be better if we could specify that -fPIC is to
be used only when building the runtimes, however this is left as a
future improvement. The release should probably be using a bootstrapping
build and passing those options to the stage that builds the runtimes
only, see https://reviews.llvm.org/D112748 for that change.

Differential Revision: https://reviews.llvm.org/D110261
2021-12-08 11:34:35 -05:00
Louis Dionne 81eda008e9 [libc++] Extract __clamp_to_integral to its own header
In addition to being more consistent with our approach for helpers, this
solves an actual issue where <cmath> was using numeric_limits but never
including the <limits> header directly. In a normal setup, this is not
an issue because the <math.h> header included by <cmath> does include
<limits>. However, I did stumble upon some code where that didn't work,
most likely because they were placing their own <math.h> header in front
of ours. I didn't bother investigating further.

Differential Revision: https://reviews.llvm.org/D115282
2021-12-08 08:33:37 -05:00
Arthur O'Dwyer b108cd7b45 [libc++] [test] Rationalize the nodiscard tests for range adaptors.
Reviewed as part of D115177.
2021-12-07 13:59:42 -05:00
Arthur O'Dwyer bd0c0e5b8c [libc++] [ranges] SFINAE-friendly "write it three times" in views::counted.
Before this patch, the new test's `CountedInvocable<int*, int*>`
would hard-error instead of SFINAEing and cleanly returning false.

Notice that views::counted specifically does NOT work with pipes;
`counted(42)` is ill-formed. This is because `counted`'s first argument
is supposed to be an iterator, not a range.

Also, mark `views::counted(it, n)` as [[nodiscard]], and test that.
(We have a general policy now that range adaptors are consistently
marked [[nodiscard]], so that people don't accidentally think that
they have side effects. This matters mostly for `reverse` and
`transform`, arguably `drop`, and just generally let's be consistent.)

Differential Revision: https://reviews.llvm.org/D115177
2021-12-07 13:59:41 -05:00
Louis Dionne c49a13a45a [libc++] Fix atomic test for _BitInt
In 6c75ab5f66, Clang deprecated _ExtInt in favor of _BitInt, which
made this test fail. This patch disables the test on older compilers
and uses the new _BitInt type instead.

Differential Revision: https://reviews.llvm.org/D115194
2021-12-07 07:30:09 -05:00
Petr Hosek ae53d02f55 Revert "Microsoft's floating-point to_chars powered by Ryu and Ryu Printf"
This reverts commit a8025e06fc since
it triggers PR52584 with debug info enabled.
2021-12-07 00:10:14 -08:00
Louis Dionne 2db67e9771 [libc++] Fix the return value of max_size()
I assume nobody ever uses std::string_view::max_size() outside of
testing. However, we should still return a value that is based on
something with a reasonable rationale. Previously, we would forget
to take into account the size of the character type stored in the
string, and this patch takes that into account.

Thanks to @mclow.lists for pointing out this issue.

Differential Revision: https://reviews.llvm.org/D114395
2021-12-06 13:53:25 -05:00
Arthur O'Dwyer dcdb07abce [libc++] Work around a Clang bug in transform_view, and regression-test.
Clang trunk rejects the new test case, but this is a Clang bug
(PR47414, 47509, 50864, 44833).

```
In module 'std' imported from /Users/aodwyer/llvm-project/libcxx/test/std/ranges/range.adaptors/range.transform/general.pass.cpp:17:
/Users/aodwyer/llvm-project/build2/include/c++/v1/__ranges/transform_view.h:85:44: error: constraints not satisfied for alias template 'range_reference_t' [with _Rp = const NonConstView]
             regular_invocable<const _Fn&, range_reference_t<const _View>>
                                           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/aodwyer/llvm-project/build2/include/c++/v1/__ranges/transform_view.h:416:25: note: in instantiation of template class 'std::ranges::transform_view<NonConstView, (lambda at /Users/aodwyer/llvm-project/libcxx/test/std/ranges/range.adaptors/range.transform/general.pass.cpp:73:71)>' requested here
      -> decltype(      transform_view(_VSTD::forward<_Range>(__range), _VSTD::forward<_Fn>(__f)))
                        ^
```

We can work around this by adding a layer of indirection: put the
problematic constraint into a named concept and Clang becomes more
amenable to SFINAE'ing instead of hard-erroring.

Drive-by simplify `range.transform/general.pass.cpp` to make it clearer
what it's actually testing in this area.

Differential Revision: https://reviews.llvm.org/D115116
2021-12-06 11:20:08 -05:00
Mark de Wever a8025e06fc Microsoft's floating-point to_chars powered by Ryu and Ryu Printf
Microsoft would like to contribute its implementation of floating-point to_chars to libc++. This uses the impossibly fast Ryu and Ryu Printf algorithms invented by Ulf Adams at Google. Upstream repos: https://github.com/microsoft/STL and https://github.com/ulfjack/ryu .

Licensing notes: MSVC's STL is available under the Apache License v2.0 with LLVM Exception, intentionally chosen to match libc++. We've used Ryu under the Boost Software License.

This patch contains minor changes from Jorg Brown at Google, to adapt the code to libc++. He verified that it works in Google's Linux-based environment, but then I applied more changes on top of his, so any compiler errors are my fault. (I haven't tried to build and test libc++ yet.) Please tell me if we need to do anything else in order to follow https://llvm.org/docs/DeveloperPolicy.html#attribution-of-changes .

Notes:

* libc++'s integer charconv is unchanged (except for a small refactoring). MSVC's integer charconv hasn't been tuned for performance yet, so you're not missing anything.
* Floating-point from_chars isn't part of this patch because Jorg found that MSVC's implementation (derived from our CRT's strtod) was slower than Abseil's. If you're unable to use Abseil or another implementation due to licensing or technical considerations, Microsoft would be delighted if you used MSVC's from_chars (and you can just take it, or ask us to provide a patch like this). Ulf is also working on a novel algorithm for from_chars.
* This assumes that float is IEEE 32-bit, double is IEEE 64-bit, and long double is also IEEE 64-bit.
* I have added MSVC's charconv tests (the whole thing: integer/floating from_chars/to_chars), but haven't adapted them to libcxx's harness at all. (These tests will be available in the microsoft/STL repo soon.)
* Jorg added int128 codepaths. These were originally present in upstream Ryu, and I removed them from microsoft/STL purely for performance reasons (MSVC doesn't support int128; Clang on Windows does, but I found that x64 intrinsics were slightly faster).
* The implementation is split into 3 headers. In MSVC's STL, charconv contains only Microsoft-written code. xcharconv_ryu.h contains code derived from Ryu (with significant modifications and additions). xcharconv_ryu_tables.h contains Ryu's large lookup tables (they were sufficiently large to make editing inconvenient, hence the separate file). The xmeow.h convention is MSVC's for internal headers; you may wish to rename them.
* You should consider separately compiling the lookup tables (see https://github.com/microsoft/STL/issues/172 ) for compiler throughput and reduced object file size.
* See https://github.com/StephanTLavavej/llvm-project/commits/charconv for fine-grained history. (If necessary, I can perform some rebase surgery to show you what Jorg changed relative to the microsoft/STL repo; currently that's all fused into the first commit.)

Differential Revision: https://reviews.llvm.org/D70631
2021-12-05 13:25:33 +01:00
Konstantin Varlamov 2d9efcfeec [libc++][ranges] Implement [special.mem.concepts].
Implement the exposition-only concepts specified in
`[special.mem.concepts]`. These are all thin wrappers over other
concepts.

Reviewed By: #libc, Quuxplusone, ldionne

Differential Revision: https://reviews.llvm.org/D114761
2021-12-02 17:58:04 -08:00
David Blaikie ff618a963a Simplify the libcxx std::string_view gdb pretty printer
Seems better to rely on the existing formatting, makes the output
smaller/simpler - this is consistent with libstdc++'s std::string_view
pretty printing too.

Differential Revision: https://reviews.llvm.org/D113244
2021-12-02 11:36:38 -08:00
Joe Loser c16b13ebf9
[libc++] Implement P1989R2: range constructor for string_view
Implement P1989R2 which adds a range constructor for `string_view`.

Adjust `operator/=` in `path` to avoid atomic constraints caching issue
getting provoked from this PR.

Add defaulted template argument to `string_view`'s "sufficient
overloads" to avoid mangling issues in `clang-cl` builds. It is a
MSVC mangling bug that this works around.

Differential Revision: https://reviews.llvm.org/D113161
2021-12-01 23:16:36 -05:00