[LV] Support vectorization of interleave-groups that require an epilog under

optsize using masked wide loads 

Under Opt for Size, the vectorizer does not vectorize interleave-groups that
have gaps at the end of the group (such as a loop that reads only the even
elements: a[2*i]) because that implies that we'll require a scalar epilogue
(which is not allowed under Opt for Size). This patch extends the support for
masked-interleave-groups (introduced by D53011 for conditional accesses) to
also cover the case of gaps in a group of loads; Targets that enable the
masked-interleave-group feature don't have to invalidate interleave-groups of
loads with gaps; they could now use masked wide-loads and shuffles (if that's
what the cost model selects).

Reviewers: Ayal, hsaito, dcaballe, fhahn

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D53668

llvm-svn: 345705

1 files changed, 5 insertions, 3 deletions

diff --git a/llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.cpp b/llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.cpp
index caa3f597445..94db56e3738 100644
--- a/llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.cpp
+++ b/llvm/lib/Target/SystemZ/SystemZTargetTransformInfo.cpp
@@ -969,10 +969,12 @@ int SystemZTTIImpl::getInterleavedMemoryOpCost(unsigned Opcode, Type *VecTy,
                                                ArrayRef<unsigned> Indices,
                                                unsigned Alignment,
                                                unsigned AddressSpace,
-                                               bool IsMasked) {
-  if (IsMasked)
+                                               bool UseMaskForCond,
+                                               bool UseMaskForGaps) {
+  if (UseMaskForCond || UseMaskForGaps)
     return BaseT::getInterleavedMemoryOpCost(Opcode, VecTy, Factor, Indices,
-                                             Alignment, AddressSpace, IsMasked);
+                                             Alignment, AddressSpace,
+                                             UseMaskForCond, UseMaskForGaps);
   assert(isa<VectorType>(VecTy) &&
          "Expect a vector type for interleaved memory op");