[MAINT] Use std::size_t from cstddef and use dpctl::tensor::ssize_t where ssize_t is used

[ndgrigorian]

This PR changes the reliance of dpctl headers on size_t being translated by the compiler by instead including cstddef and replacing size_t with std::size_t throughout.

Additionally, using dpctl::tensor::ssize_t is used wherever ssize_t comes up.

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[github-actions]

View rendered docs @ https://intelpython.github.io/dpctl/pulls/1950/index.html

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_358 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[oleksandr-pavlyk]

@ndgrigorian Looks like these two instances were missed:

(dev_dpctl) opavlyk@opavlyk-mobl:~/repos/dpctl$ grep -r size_t dpctl/tensor/libtensor/ | grep -v "std::size_t" | grep -v "ssize_t" | grep -v "size_to"
dpctl/tensor/libtensor/include/kernels/elementwise_functions/trunc.hpp:                              size_t nelems,
dpctl/tensor/libtensor/include/kernels/elementwise_functions/trunc.hpp:                   size_t nelems,

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_359 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[ndgrigorian]

@ndgrigorian Looks like these two instances were missed:

(dev_dpctl) opavlyk@opavlyk-mobl:~/repos/dpctl$ grep -r size_t dpctl/tensor/libtensor/ | grep -v "std::size_t" | grep -v "ssize_t" | grep -v "size_to"
dpctl/tensor/libtensor/include/kernels/elementwise_functions/trunc.hpp:                              size_t nelems,
dpctl/tensor/libtensor/include/kernels/elementwise_functions/trunc.hpp:                   size_t nelems,

I've pushed a change fixing these, good catch!

[oleksandr-pavlyk]

@ndgrigorian These changes look good to me. I think it is ready for review and ready to be merged in.

One thing to check is whether changes here might conflict with changes in feature/topk branch

[ndgrigorian]

@ndgrigorian These changes look good to me. I think it is ready for review and ready to be merged in.

One thing to check is whether changes here might conflict with changes in feature/topk branch

I'll go ahead and check if they do. I will also have to rebase onto master and check for more instances with the accumulator improvement PR merged.

[oleksandr-pavlyk]

The coverage workflow failed with 8 ctest failures related to sycl::kernel_bundle and sycl::kernel

[oleksandr-pavlyk]

The reason for failures is the std::size_t should not he used in declarations and definitions of EXTERN "C" functions due to name mangling

[oleksandr-pavlyk]

The C compatible type is defined in "stddef.h"

[ndgrigorian]

The reason for failures is the std::size_t should not he used in declarations and definitions of EXTERN "C" functions due to name mangling

Uses in libsyclinterface have been removed

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_366 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_366 ran successfully.
Passed: 895
Failed: 1
Skipped: 118

[coveralls]

coverage: 87.659%. remained the same
when pulling ab85a42 on use-std-size-t-cstddef
into f7cb1b1 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_367 ran successfully.
Passed: 893
Failed: 3
Skipped: 118

[ndgrigorian]

@ndgrigorian These changes look good to me. I think it is ready for review and ready to be merged in.

One thing to check is whether changes here might conflict with changes in feature/topk branch

Unfortunately there are conflicts in merge_sort.hpp and radix_sort.hpp

It may be best to merge this after topk

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_370 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_369 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[ndgrigorian]

@oleksandr-pavlyk
I've also reverted use of std::size_t in _host_task_utils.hpp

In the process, I've also noticed that we are using py::ssize_t as the type for the number of elements in an array for get_size method and in size Python equivalent, while throughout libtensor Python bindings, we use size_t to represent the number of elements.

This inconsistency can be resolved in a later PR, but we should probably use size_t everywhere for this.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_369 ran successfully.
Passed: 895
Failed: 1
Skipped: 118