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
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
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
Patch from Arthur O'Dwyer.
`__user_alloc_construct_impl` is used by <experimental/memory_resource>, but
this `__user_alloc_construct` is never used.
Also, `<experimental/memory_resource>` doesn't need a full definition of
`std::tuple`; just the forward declaration in `<__tuple>` will suffice.
Reviewed as https://reviews.llvm.org/D46806
llvm-svn: 334069
Patch from Arthur O'Dwyer.
In the TS, `uses_allocator` construction for `pair` tried to use an allocator
type of `memory_resource*`, which is incorrect because `memory_resource*` is
not an allocator type. LWG 2969 fixed it to use `polymorphic_allocator` as the
allocator type instead.
https://wg21.link/lwg2969
(D47090 included this in `<memory_resource>`; at Eric's request, I've split
this out into its own patch applied to the existing
`<experimental/memory_resource>` instead.)
Reviewed as https://reviews.llvm.org/D47109
llvm-svn: 333384
Summary:
This patch improves how libc++ handles min/max macros within the headers. Previously libc++ would undef them and emit a warning.
This patch changes libc++ to use `#pragma push_macro` to save the macro before undefining it, and `#pragma pop_macro` to restore the macros and the end of the header.
Reviewers: mclow.lists, bcraig, compnerd, EricWF
Reviewed By: EricWF
Subscribers: cfe-commits, krytarowski
Differential Revision: https://reviews.llvm.org/D33080
llvm-svn: 304357
The name _LIBCPP_TYPE_VIS_ONLY is no longer accurate because both
_LIBCPP_TYPE_VIS and _LIBCPP_TYPE_VIS_ONLY expand to
__attribute__((__type_visibility__)) with Clang. The only remaining difference
is that _LIBCPP_TYPE_VIS_ONLY can be applied to templates whereas
_LIBCPP_TYPE_VIS cannot (due to dllimport/dllexport not being allowed on
templates).
This patch renames _LIBCPP_TYPE_VIS_ONLY to _LIBCPP_TEMPLATE_VIS.
llvm-svn: 291035
Brian Gesiak