[BYOC][Optimization] Run accelerator specific optimizations #6068

Merged

masahi merged 2 commits intoapache:masterfrom zhiics:ext_opt

Jul 16, 2020

+84-31

Commits on Jul 14, 2020

register and invoke optimization pipeline for external codegen
zhiics
committed

Commits on Jul 15, 2020

add unit test
zhiics
committed