The Standard specifies which types are stored in the basic_format_arg
"variant" and which types are stored as a handle. Libc++ stores
additional types in the "variant". During a reflector discussion
@jwakely mention this is user observable; visit_format_arg uses the type
instead of a handle as argument.
This optimization is useful and will probably be used for other small
types in the future. To be conferment the visitor creates a handle and
uses that as argument. There is a second visitor so the formatter can
still directly access the 128-bit integrals.
The test for the visitor and get has been made public too, there is no
reason not too. The 128-bit integral types are required by the Standard,
when they are available.
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D138052
This implements a not accepted LWG issue. Not doing so would require
integral types to use the handle class instead of being directly stored
in the basic_format_arg.
The previous code used `std::forward` in places where it wasn't required
by the Standard. These are now removed.
Implements:
- P2418R2 Add support for std::generator-like types to std::format
- LWG 3631 basic_format_arg(T&&) should use remove_cvref_t<T> throughout
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D127570
This optimizes the __format_arg_store type to allow a more efficient
storage of the basic_format_args.
It stores the data in two arrays:
- A struct with the tag of the exposition only variant's type and the
offset of the element in the data array. Since this array only depends
on the type information it's calculated at compile time and can be
shared by different instances of this class.
- The arguments converted to the types used in the exposition only
variant of basic_format_arg. This means the packed data can be
directly copied to an element of this variant.
The new code uses rvalue reference arguments in preparation for P2418.
The handle class also has some changes to prepare for P2418. The real
changed for P2418 will be done separately, but these parts make it
easier to implement that paper.
Some parts of existing test code are removed since they were no longer
valid after the changes, but new tests have been added.
Implements parts of:
- P2418 Add support for std::generator-like types to std::format
Completes:
- LWG3473 Normative encouragement in non-normative note
Depends on D121138
Reviewed By: #libc, vitaut, Mordante
Differential Revision: https://reviews.llvm.org/D121514
D123182 fixes a bug in Clang's overload resolution. After it landed it
was discovered `basic_format_arg`'s constructors contains this bug. This
fixes the bug in libc++, unblocking D123182.
The code has been tested in combination with D123182.
Reviewed By: royjacobson, #libc
Differential Revision: https://reviews.llvm.org/D124103
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
This commit reverts 5aaefa51 (and also partly 7f285f48e7 and b6d75682f9,
which were related to the original commit). As landed, 5aaefa51 had
unintended consequences on some downstream bots and didn't have proper
coverage upstream due to a few subtle things. Implementing this is
something we should do in libc++, however we'll first need to address
a few issues listed in https://reviews.llvm.org/D106124#3349710.
Differential Revision: https://reviews.llvm.org/D120683
libc++ has started splicing standard library headers into much more
fine-grained content for maintainability. It's very likely that outdated
and naive tooling (some of which is outside of LLVM's scope) will
suggest users include things such as <__ranges/access.h> instead of
<ranges>, and Hyrum's law suggests that users will eventually begin to
rely on this without the help of tooling. As such, this commit
intends to protect users from themselves, by making it a hard error for
anyone outside of the standard library to include libc++ detail headers.
Differential Revision: https://reviews.llvm.org/D106124
This is the first step towards disentangling the debug mode and assertions
in libc++. This patch doesn't make any functional change: it simply moves
_LIBCPP_ASSERT-related stuff to its own file so as to make it clear that
libc++ assertions and the debug mode are different things. Future patches
will make it possible to enable assertions without enabling the debug
mode.
Differential Revision: https://reviews.llvm.org/D119769
In D117811 @Quuxplusone pointed out the friend declarations don't need
to be qualified. Removing the qualification should avoid needing to add
a GCC work-around when changing _VSTD to std.
Reviewed By: Quuxplusone, philnik, #libc, ldionne
Differential Revision: https://reviews.llvm.org/D118719
This implements the handler according to P0645. P2418 changes the wording
in the Standard. That isn't implemented and requires changes in more
places. LWG3631 applies modifications to P2418, but is currently
unresolved.
Implements parts of:
* P0645 Text Formatting
Depends on D115989
Reviewed By: ldionne, #libc
Differential Revision: https://reviews.llvm.org/D115991
This implements the last required formatter specialization.
Completes:
- LWG 3251 Are std::format alignment specifiers applied to string arguments?
- LWG 3340 Formatting functions should throw on argument/format string mismatch in §[format.functions]
- LWG 3540 §[format.arg] There should be no const in basic_format_arg(const T* p)
Implements parts of:
- P0645 Text Formatting
Depends on D114001
Reviewed By: ldionne, vitaut, #libc
Differential Revision: https://reviews.llvm.org/D115988
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
D103357 added some new concepts. Since the header `<concepts>` has moved
all its concepts to a separate header these new concepts feel out of
place. Move them to the appropriate header.
Reviewed By: #libc, Quuxplusone, ldionne
Differential Revision: https://reviews.llvm.org/D109075
This implements the struct `__format_arg_store` and its dependencies:
* the class basic_format_arg,
* the class basic_format_args,
* the class basic_format_context,
* the function make_format_args,
* the function wmake_format_args,
* the function visit_format_arg,
* several Standard required typedefs.
The following parts will be implemented in a later patch:
* the child class `basic_format_arg::handle`,
* the function `basic_format_arg::basic_format_arg(const T* p)`.
The following extension has been implemented:
* the class basic_format_arg supports `__[u]int128_t` on platform where libc++ supports 128 bit integrals.
Implements parts of:
* P0645 Text Formatting
Completes:
* LWG3371 visit_format_arg and make_format_args are not hidden friends
* LWG3542 basic_format_arg mishandles basic_string_view with custom traits
Note https://mordante.github.io/blog/2021/06/05/format.html gives a bit more information about the goals and non-goals of this initial patch series.
Reviewed By: #libc, ldionne, vitaut
Differential Revision: https://reviews.llvm.org/D103357
Mark de Wever