[PET-to-MLIR] fixed tests and negative loop traversal merge#10

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Komisarczyk wants to merge 2 commits intoLoopTactics:pet-mlirfrom

Komisarczyk:pet-mlir_temp

Commits on Jul 1, 2020

[PET-to-MLIR] fixed references for syrk trisolv
Komisarczyk
committed

Commits on Jul 2, 2020

[PET-to-MLIR] fix the negative loop traversal
Komisarczyk
committed