IntelPython / dpnp / 32940309211

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Committed by web-flow

Commit Message

Fix abort in `dpnp.all` / `dpnp.any` over an empty axis (#3021)

`dpnp.all` and `dpnp.any` aborted the process when reducing over an
empty axis, e.g.:

```python
import dpnp
dpnp.all(dpnp.zeros((0, 3, 4)))          # reduces over 0 elements
dpnp.any(dpnp.zeros((0, 3, 4)), axis=0)  # zero-length reduced axis
```

`_boolean_reduction` always allocated a temporary and launched the
reduction kernel. When the reduced extent is zero (a reduced dimension
has length 0), the kernel is submitted with a zero-sized `nd_range`.
That is a silent no-op on a SYCL runtime built with `NDEBUG`, but aborts
on an assertions-enabled runtime, where `adjustNDRangePerKernel` asserts
`NDR.LocalSize[0] == 0` whenever `GlobalSize[0]` is `0`:

```
Assertion `NDR.LocalSize[0] == 0' failed.
  .../sycl/source/detail/scheduler/commands.cpp
  void sycl::_V1::detail::adjustNDRangePerKernel(...)
```

This PR proposes to short-circuit in `_boolean_reduction` when the
(permuted) input has no elements, building the result directly with the
reduction identity instead of launching a kernel. `all` uses identity
`True`, `any` uses `False`. A single `x_tmp.size == 0` check covers both
empty sub-cases correctly:

- empty output (a non-reduced dimension is zero) — the result is an
empty array, so the fill value is irrelevant;
- zero-length reduced axis (the output is non-empty) — the reduction
identity is the answer, e.g. `all([]) is True`, `any([]) is False`.

Note, the issue was identified when building with the nightly LLVM SYCL
compiler and
[running](https://github.com/antonwolfy/dpnp/actions/runs/31585418522/job/94078011200)
dpnp tests.
And the tests are
[passing](https://github.com/antonwolfy/dpnp/actions/runs/31595647966/job/94110377635)
now without any crash.

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