Commit Graph

2 Commits

Author SHA1 Message Date
Philip Reames
af690c9cd3 [RewriteStatepointsForGC] Fix another order of iteration bug
It turns out the naming of inserted phis and selects is sensative to the order in which two sets are iterated.  We need to nail this down to avoid non-deterministic output and possible test failures.  

The modified test is the one I first noticed something odd in.  The change is making it more strict to report the error.  With the test change, but without the code change, the test fails roughly 1 in 5.  With the code change, I've run ~30 runs without error.

Long term, the right fix here is to adjust the naming scheme.  I'm checking in this hack to avoid any possible non-determinism in the tests over the weekend.  HJust because I only noticed one case doesn't mean it's actually the only case.  I hope to get to the right change Monday.

std->llvm data structure changes bugfix change #3



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230835 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 01:52:09 +00:00
Philip Reames
a3f59e44cd [RewriteStatepointsForGC] Add tests for the base pointer identification algorithm
These tests cover the 'base object' identification and rewritting portion of RewriteStatepointsForGC.  These aren't completely exhaustive, but they've proven to be reasonable effective over time at finding regressions.

In the process of porting these tests over, I found my first "cleanup per llvm code style standards" bug.  We were relying on the order of iteration when testing the base pointers found for a derived pointer.  When we switched from std::set to DenseSet, this stopped being a safe assumption.  I'm suspecting I'm going to find more of those.  In particular, I'm now really wondering about the main iteration loop for this algorithm.  I need to go take a closer look at the assumptions there.

I'm not really happy with the fact these are testing what is essentially debug output (i.e. enabled via command line flags).  Suggestions for how to structure this better are very welcome.  



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@230818 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-28 00:20:48 +00:00