When dumping results of StackLifetime, it will print the following

log:

BB  [7, 8): begin {}, end {}, livein {}, liveout {}
BB  [1, 2): begin {}, end {}, livein {}, liveout {}
...

But it is not convenient to know what the basic block is.
So I add the basic block name to it.

Reviewed By: vitalybuka
TestPlan: check-llvm
Differential Revision: https://reviews.llvm.org/D87152