Summary:
The analysis of the store sequence goes in straight order - from the
first store to the last. Bu the best opportunity for vectorization will
happen if we're going to use reverse order - from last store to the
first. It may be best because usually users have some initialization
part + further processing and this first initialization may confuse
SLP vectorizer.
Reviewers: RKSimon, hfinkel, mkuper, spatel
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D39606
llvm-svn: 317821