experiment: change phase/step/substep display
experiment: change phase/step/substep display

Make it easier to spot the elements in log output.


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Former-commit-id: 426e920cc16a79fb40fd9ca4373c5938f0000124
PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild,PolyJIT/benchbuild