Implements:
- P2291R3 Add Constexpr Modifiers to Functions to_chars and from_chars for
Integral Types in <charconv> Header
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D131317
Implementing the paper
P2291R3 Add Constexpr Modifiers to Functions to_chars and from_chars for
Integral Types in <charconv> Header
Gives issues in language versions prior to C++17. As suggested in
D131855 disable the code prior to C++17. This removes libc++'s
extension.
Reviewed By: ldionne, #libc_vendors, #libc, philnik
Differential Revision: https://reviews.llvm.org/D133216
This was discovered as an issue in D131317.
Depends on D131835
Reviewed By: #libc, var-const, ldionne, philnik
Differential Revision: https://reviews.llvm.org/D131836
This is required by the Standard and makes it possible to add full
128-bit support to format.
The patch also fixes 128-bit from_chars "support". One unit test
required a too large value, this failed on 128-bit; the fix was to add
more characters to the input.
Note only base 10 has been optimized. Other bases can be optimized.
Note the 128-bit lookup table could be made smaller. This will be done later. I
really want to get 128-bit working in to_chars and format in the upcomming
LLVM 15 release, these optimizations aren't critical.
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D128929
After moving the std::to_chars base 10 implementation from the dylib to
the header the integral overloads of std::to_chars are available on all
platforms.
Remove the _LIBCPP_AVAILABILITY_TO_CHARS availability macro and update
the tests.
Depends on D125704
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D125745
Since those features are general properties of the environment, it makes
sense to use them from libc++abi too, and so the name libcpp-has-no-xxx
doesn't make sense.
Differential Revision: https://reviews.llvm.org/D126482
All supported compilers that support C++20 now support concepts. So, remove
`_LIB_LIBCPP_HAS_NO_CONCEPTS` in favor of `_LIBCPP_STD_VER > 17`. Similarly in
the tests, remove `// UNSUPPORTED: libcpp-no-concepts`.
Differential Revision: https://reviews.llvm.org/D121528
These printf()s fail to compile like so on hexagon:
.../tools/llvm-top/libcxx/test/std/utilities/charconv/charconv.msvc/test.cpp:94:23: error: format specifies type 'unsigned int' but the argument has type 'unsigned long' [-Werror,-Wformat]
printf("%u ", elem);
~~ ^~~~
%lu
.../tools/llvm-top/libcxx/test/std/utilities/charconv/charconv.msvc/test.cpp:569:56: error: format specifies type 'unsigned int' but the argument has type 'uint32_t' (aka 'unsigned long') [-Werror,-Wformat]
fprintf(stderr, "%s failed for 0x%08X\n", msg, bits);
~~~~ ^~~~
%08lX
.../tools/llvm-top/libcxx/test/std/utilities/charconv/charconv.msvc/test.cpp:1096:43: error: format specifies type 'unsigned int' but the argument has type 'unsigned long' [-Werror,-Wformat]
printf("Randomized test cases: %u\n", PrefixesToTest * Fractions);
~~ ^~~~~~~~~~~~~~~~~~~~~~~~~~
%lu
Differential Revision: https://reviews.llvm.org/D120532
The code in libc++ already satisfy the requirements of LWG-3373. Since
the issue was written to specifically allow the types to be used in
structured bindings, tests have been added to validate the new
requirement.
Implements
LWG-3373 {to,from}_chars_result and format_to_n_result need the "we really mean what we say" wording
Reviewed By: #libc, ldionne
Differential Revision: https://reviews.llvm.org/D117337
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
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
Vendors take libc++ and ship it in various ways. Some vendors might
ship it differently from what upstream LLVM does, i.e. the install
location might be different, some ABI properties might differ, etc.
In the past few years, I've come across several instances where
having a place to test some of these properties would have been
incredibly useful. I also just got bitten by the lack of tests
of that kind, so I'm adding some now.
The tests added by this commit for Apple platforms have numerous
TODOs that capture discrepancies between the upstream LLVM CMake
and the slightly-modified build we perform internally to produce
Apple's system libc++. In the future, the goal would be to upstream
all those differences so that it's possible to build a faithful
Apple system libc++ with the upstream LLVM sources only.
But this isn't only useful for Apple - this lays out the path for
any vendor being able to add their own checks (either upstream or
downstream) to libc++.
Differential Revision: https://reviews.llvm.org/D110736
Before this patch, we had features named 'libc++', 'libstdc++' and
'msvc' to describe the three implementations that use our test suite.
This patch renames them to 'stdlib=libc++', 'stdlib=libstdc++', etc
to avoid confusion between MSVC's STL and the MSVC compiler (or Clang
in MSVC mode).
Furthermore, this prepares the terrain for adding support for additional
"implementations" to the test suite. Basically, I'd like to be able to
treat Apple's libc++ differently from LLVM's libc++ for the purpose of
testing, because those effectively behave in different ways in some aspects.
Now that Lit supports regular expressions inside XFAIL & friends, it is
much easier to write Lit annotations based on the triple.
Differential Revision: https://reviews.llvm.org/D104747
This fixes a long standing issue where the triple is not always set
consistently in all configurations. This change also moves the
back-deployment Lit features to using the proper target triple
instead of using something ad-hoc.
This will be necessary for using from scratch Lit configuration files
in both normal testing and back-deployment testing.
Differential Revision: https://reviews.llvm.org/D102012
Some of Microsoft's unit tests in D70631 fail because libc++'s
implementation of std::chars_format isn't a proper bitmask type. Adding
the required functions to make std::chars_format a proper bitmask type.
Implements parts of P0067: Elementary string conversions
Differential Revision: https://reviews.llvm.org/D97115
C++98 and C++03 are effectively aliases as far as Clang is concerned.
As such, allowing both std=c++98 and std=c++03 as Lit parameters is
just slightly confusing, but provides no value. It's similar to allowing
both std=c++17 and std=c++1z, which we don't do.
This was discovered because we had an internal bot that ran the test
suite under both c++98 AND c++03 -- one of which is redundant.
Differential Revision: https://reviews.llvm.org/D80926
The libc++ test suite has a lot of old Lit features used to XFAIL tests
and mark them as UNSUPPORTED. Many of them are to workaround problems on
old compilers or old platforms. As time goes by, it is good to go and
clean those up to simplify the configuration of the test suite, and also
to reflect the testing reality. It's not useful to have markup that gives
the impression that e.g. clang-3.3 is supported, when we don't really
test on it anymore (and hence several new tests probably don't have the
necessary markup on them).
Summary:
Freestanding is *weird*. The standard allows it to differ in a bunch of odd
manners from regular C++, and the committee would like to improve that
situation. I'd like to make libc++ behave better with what freestanding should
be, so that it can be a tool we use in improving the standard. To do that we
need to try stuff out, both with "freestanding the language mode" and
"freestanding the library subset".
Let's start with the super basic: run the libc++ tests in freestanding, using
clang as the compiler, and see what works. The easiest hack to do this:
In utils/libcxx/test/config.py add:
self.cxx.compile_flags += ['-ffreestanding']
Run the tests and they all fail.
Why? Because in freestanding `main` isn't special. This "not special" property
has two effects: main doesn't get mangled, and main isn't allowed to omit its
`return` statement. The first means main gets mangled and the linker can't
create a valid executable for us to test. The second means we spew out warnings
(ew) and the compiler doesn't insert the `return` we omitted, and main just
falls of the end and does whatever undefined behavior (if you're luck, ud2
leading to non-zero return code).
Let's start my work with the basics. This patch changes all libc++ tests to
declare `main` as `int main(int, char**` so it mangles consistently (enabling us
to declare another `extern "C"` main for freestanding which calls the mangled
one), and adds `return 0;` to all places where it was missing. This touches 6124
files, and I apologize.
The former was done with The Magic Of Sed.
The later was done with a (not quite correct but decent) clang tool:
https://gist.github.com/jfbastien/793819ff360baa845483dde81170feed
This works for most tests, though I did have to adjust a few places when e.g.
the test runs with `-x c`, macros are used for main (such as for the filesystem
tests), etc.
Once this is in we can create a freestanding bot which will prevent further
regressions. After that, we can start the real work of supporting C++
freestanding fairly well in libc++.
<rdar://problem/47754795>
Reviewers: ldionne, mclow.lists, EricWF
Subscribers: christof, jkorous, dexonsmith, arphaman, miyuki, libcxx-commits
Differential Revision: https://reviews.llvm.org/D57624
llvm-svn: 353086
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
There were 3 tests with 'int main(void)', and 6 with the return type on a different line. I'm about to send a patch for main in tests, and this NFC change is unrelated.
llvm-svn: 350770
Summary:
Major QoI considerations:
- The facility is backported to C++14, same as libstdc++.
- Efforts have been made to minimize the header dependencies.
- The design is friendly to the uses of MSVC intrinsics (`__emulu`, `_umul128`, `_BitScanForward`, `_BitScanForward64`) but not implemented; future contributions are welcome.
Thanks to Milo Yip for contributing the implementation of `__u64toa` and `__u32toa`.
References:
https://wg21.link/p0067r5https://wg21.link/p0682r1
Reviewers: mclow.lists, EricWF
Reviewed By: mclow.lists
Subscribers: ldionne, Quuxplusone, christof, mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D41458
llvm-svn: 338479
Mark de Wever