Depends On D104850
Add a test that verifies that canonicalization removes all async overheads if it is statically known that the scf.parallel operation will be computed using a single block.
Reviewed By: herhut
Differential Revision: https://reviews.llvm.org/D104891
Depends On D104780
Recursive work splitting instead of sequential async tasks submission gives ~20%-30% speedup in microbenchmarks.
Algorithm outline:
1. Collapse scf.parallel dimensions into a single dimension
2. Compute the block size for the parallel operations from the 1d problem size
3. Launch parallel tasks
4. Each parallel task reconstructs its own bounds in the original multi-dimensional iteration space
5. Each parallel task computes the original parallel operation body using scf.for loop nest
Reviewed By: herhut
Differential Revision: https://reviews.llvm.org/D104850