The dominance of the generated non-affine subregion block was based on
the scop's merge block, therefore resulted in an invalid DominanceTree.
It resulted in some values as assumed to be unusable in the actual
generated exit block.
We detect the case that the exit block has been moved and decide
dominance using the BB at the original exit. If we create another exit
node, that exit nodes is dominated by the one generated from where the
original exit resides. This fixes llvm.org/PR25438 and part of
llvm.org/PR25439.
llvm-svn: 252526
It introduced indeterminism as it was iterating over an address-indexed
hashtable. The corresponding bug PR25438 will be fixed in a successive
commit.
llvm-svn: 252522
After loop versioning, a dominance check of a non-affine subregion's
exit node causes the dominance check to always fail on any block in the
subregion if it shares the same exit block with the scop. The
subregion's exit block has become polly_merge_new_and_old, which also
receives the control flow of the generated code. This would cause that
any value for implicit stores is assumed to be not from the scop.
We check dominance with the generated exit node instead.
This fixes llvm.org/PR25438
llvm-svn: 252375
Michael Kruse