This follows up on:
https://gcc.gnu.org/pipermail/libstdc++/2025-May/061459.html
The changes are:
* Fix layout_stride::strides; and add tests.
* Add accessors for ranges of static and dynamic extents.
* Use them to implement __fwd_prod and __rev_prod.
* Remove public members with protected names from extents,
by using friends and the accessors instead.
* Reduce runtime cost of __is_representable_extents by
separating static and dynamic extents.
* Remove __layout_extents.
* Move private ctors to bottom of class and directly
initialize _M_extents.
* Implement precondition in layout_{left,right}(layout_stride)
using `*this == __other`.
* Twice: Use lambda instead of *_impl function.
* Various smaller improvements to the tests.
Luc Grosheintz (6):
libstdc++: Implement layout_left from mdspan.
libstdc++: Add tests for layout_left.
libstdc++: Implement layout_right from mdspan.
libstdc++: Add tests for layout_right.
libstdc++: Implement layout_stride from mdspan.
libstdc++: Add tests for layout_stride.
libstdc++-v3/include/std/mdspan | 670 +++++++++++++++++-
.../mdspan/layouts/class_mandate_neg.cc | 42 ++
.../23_containers/mdspan/layouts/ctors.cc | 401 +++++++++++
.../23_containers/mdspan/layouts/mapping.cc | 569 +++++++++++++++
.../23_containers/mdspan/layouts/stride.cc | 494 +++++++++++++
5 files changed, 2175 insertions(+), 1 deletion(-)
create mode 100644
libstdc++-v3/testsuite/23_containers/mdspan/layouts/class_mandate_neg.cc
create mode 100644 libstdc++-v3/testsuite/23_containers/mdspan/layouts/ctors.cc
create mode 100644
libstdc++-v3/testsuite/23_containers/mdspan/layouts/mapping.cc
create mode 100644
libstdc++-v3/testsuite/23_containers/mdspan/layouts/stride.cc
--
2.49.0
