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
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@345281 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@345214 91177308-0d34-0410-b5e6-96231b3b80d8
Libc++ is used as a system library on macOS and iOS (amongst others). In order
for users to be able to compile a binary that is intended to be deployed to an
older version of the platform, clang provides the
availability attribute <https://clang.llvm.org/docs/AttributeReference.html#availability>_
that can be placed on declarations to describe the lifecycle of a symbol in the
library.
See docs/DesignDocs/AvailabilityMarkup.rst for more information.
Differential Revision: https://reviews.llvm.org/D31739
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@302172 91177308-0d34-0410-b5e6-96231b3b80d8
This patch XFAIL's a number of tests under test/libcxx when on Windows.
These failures need more investigation or patches to either Clang or libc++
but for now we don't want them to prevent the bot from going green.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@300941 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch implements the library side of P0035R4. The implementation is thanks to @rsmith.
In addition to the C++17 implementation, the library implementation can be explicitly turned on using `-faligned-allocation` in all dialects.
Reviewers: mclow.lists, rsmith
Subscribers: rsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D25591
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@284206 91177308-0d34-0410-b5e6-96231b3b80d8
This patch addresses the following issues in the test suite:
1. Move "std::bad_array_length" test from std/ to libcxx/ test directory
since the feature is not a part of the standard.
2. Rename "futures.tas" test directory to "futures.task" since that is the
correct stable name.
3. Move tests for "packaged_task<T>::result_type" from std/ to libcxx/
test directory since the typedef is a libc++ extension.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@271430 91177308-0d34-0410-b5e6-96231b3b80d8
