Summary:
Alloca promotion pass not dealing with non-canonical input
Added some additional checks so the pass simply backs-off forms it can't deal with (non-canonical)
Also added some test cases in non-canonical form to check that it no longer crashes
Subscribers: arsenm, kzhuravl, wdng, nhaehnle, yaxunl, tpr, t-tye
Differential Revision: https://reviews.llvm.org/D31710
llvm-svn: 305079
David Stuttard