llvm/polly/lib/External/isl/test_inputs/convex11.polylib

3 4
1 0 -1 6
1 -1 1 1
1 1 1 -10

3 4
1 1 0 -4
1 -1 -1 8
1 -1 1 1

3 4
1 0 -1 6
1 1 0 -4
1 -1 1 1