tree 362756b7117593a455f5bf47c13efaa4f3c75c1d
parent b09504895945a7053f82097281a61320e128db53
author Chandler Carruth <chandlerc@gmail.com> 1479842611 +0000
committer Chandler Carruth <chandlerc@gmail.com> 1479842611 +0000

[LCG] Add utilities to compute parent and ascestor relationships between
SCCs.

These will be fairly expensive routines to call and might be abused in
real code, but are quite useful when debugging or in asserts and are
reasonable and well formed properties to query.

I've used one of them in an assert that was requested in a code review
here. In subsequent commits I'll start using these routines more
heavily, for example in unittests etc. But this at least gets the
groundwork in place.

Differential Revision: https://reviews.llvm.org/D25506

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287682 91177308-0d34-0410-b5e6-96231b3b80d8