Matthew Simpson bdd1452784 [SLP] Vectorize the index computations of getelementptr instructions.
This patch seeds the SLP vectorizer with getelementptr indices. The primary
motivation in doing so is to vectorize gather-like idioms beginning with
consecutive loads (e.g., g[a[0] - b[0]] + g[a[1] - b[1]] + ...). While these
cases could be vectorized with a top-down phase, seeding the existing bottom-up
phase with the index computations avoids the complexity, compile-time, and
phase ordering issues associated with a full top-down pass. Only bundles of
single-index getelementptrs with non-constant differences are considered for
vectorization.

Differential Revision: http://reviews.llvm.org/D14829

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257800 91177308-0d34-0410-b5e6-96231b3b80d8
2016-01-14 20:46:27 +00:00
..
2015-12-18 23:46:42 +00:00
2016-01-13 23:13:38 +00:00