In-Place Dense Matrix Transposition

[jessicapriebe]

Added a new kernel for In-Place Dense Matrix Transposition, based on Algorithm 467 by Brenner (DOI: 10.1145/355611.362542).

Performance:
Compared to the existing kernel, the added method provides significant performance benefits in a single-threaded context:

• Faster in 82.7% of cases.
• Average speedup of 25.8%.

Note:
Performance measurements were restricted to cases where the existing kernel yields correct results. Similar or even better performance could be observed across all cases.

Future Work:
The divisors operate on different indices of the array, allowing for parallelization and offering additional performance improvements in multi-threaded scenarios.

@mboehm7

[Baunsgaard]

Very cool, thanks for the PR, and finding bugs in my transpose in place.

I have only a few comments.

[codecov]

Codecov Report

Attention: Patch coverage is 94.87179% with 6 lines in your changes missing coverage. Please review.

Project coverage is 72.30%. Comparing base (f8522a7) to head (c398bfa).
Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
...ache/sysds/runtime/matrix/data/LibMatrixReorg.java	94.87%	3 Missing and 3 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2199      +/-   ##
============================================
+ Coverage     71.88%   72.30%   +0.42%     
- Complexity    44701    45023     +322     
============================================
  Files          1449     1452       +3     
  Lines        169182   169417     +235     
  Branches      32980    33059      +79     
============================================
+ Hits         121617   122498     +881     
+ Misses        38237    37602     -635     
+ Partials       9328     9317      -11     

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[mboehm7]

LGTM - thanks for the new kernel @jessicapriebe. I'll merge it in.