[PATCH] D43620: [Pipeliner] Fixed node order issue related to zero latency edges

[Jan-Willem Roorda via Phabricator via llvm-commits]

jwroorda added a comment.

> This change causes some issues. The following testcase crashes or runs until memory is exhausted.

Thanks for the feedback. I have been able to reproduce the issue.

However, I do not think the change necessarily *causes* the issue. Instead, I believe that it exposes an already existing issue.
The node order generated by the change is valid. I believe that the rest of the SWP-algorithm should be able to handle it.

I did some debugging:
For the given example, after the node order is generated, the pipeliner is able to find a schedule with II=1. 
However, when the "orderDependence" function is called from inside the "finalizeSchedule" function, 
it gets caught in an infinite recursion. This warrants further investigation.


Repository:
  rL LLVM

https://reviews.llvm.org/D43620