Change split functions to work on box instead of chunk

[psalz]

chunk is a purely user-facing type (and of questionable usefulness at that), and since all of our internal tracking is built around box, splitting should follow suit.

[github-actions]

Check-perf-impact results: (000e2892abb21ddd1ae413a5c86d7d95)

❓ No new benchmark data submitted. ❓
Please re-run the microbenchmarks and include the results if your commit could potentially affect performance.

[github-actions]

⚠️ Clang-Tidy found issue(s) with the introduced code (1/1)

[coveralls]

Pull Request Test Coverage Report for Build 15258506201

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 58 of 58 (100.0%) changed or added relevant lines in 3 files are covered.
• 19 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.01%) to 95.061%

---

Files with Coverage Reduction	New Missed Lines	%
src/config.cc	1	80.72%
src/runtime.cc	1	92.29%
src/scheduler.cc	1	98.78%
include/utils.h	3	86.11%
src/live_executor.cc	3	95.33%
src/receive_arbiter.cc	4	96.09%
src/backend/sycl_backend.cc	6	89.86%

Totals
Change from base Build 12390656669:	0.01%
Covered Lines:	7146
Relevant Lines:	7251

---

💛 - Coveralls

[GagaLP]

Nice

[fknorr]

I like it!

If I'm not mistaken you could also define command_graph_generator::assigned_chunk in terms of boxes and get rid of even more casts without much hassle - buffer_access_map already operates on boxes.

Also, a drive-by suggestion:

diff --git a/src/command_graph_generator.cc b/src/command_graph_generator.cc
index da56682e..3cfb6d22 100644
--- a/src/command_graph_generator.cc
+++ b/src/command_graph_generator.cc
@@ -117,11 +117,9 @@ std::vector<const command*> command_graph_generator::build_task(const task& tsk)
 }

 void command_graph_generator::report_overlapping_writes(const task& tsk, const box_vector<3>& local_chunks) const {
-       const chunk<3> full_chunk{tsk.get_global_offset(), tsk.get_global_size(), tsk.get_global_size()};
-
        // Since this check is run distributed on every node, we avoid quadratic behavior by only checking for conflicts between all local chunks and the
        // region-union of remote chunks. This way, every conflict will be reported by at least one node.
-       const box<3> global_chunk(subrange(full_chunk.offset, full_chunk.range));
+       const box<3> global_chunk(subrange(tsk.get_global_offset(), tsk.get_global_size()));
        auto remote_chunks = region_difference(global_chunk, region(box_vector<3>(local_chunks))).into_boxes();

        // detect_overlapping_writes takes a single box_vector, so we concatenate local and global chunks (the order does not matter)

[github-actions]

Check-perf-impact results: (17d2daea565336edd0421cacd8138ced)

❓ No new benchmark data submitted. ❓
Please re-run the microbenchmarks and include the results if your commit could potentially affect performance.