tree db45cc9a92bc6d748168c96fe01465df5b4003a5
parent 4245638a61731c67b8355335e1d4785ea8ebc3f0
author Eli Friedman <efriedma@quicinc.com> 1549585415 +0000
committer Eli Friedman <efriedma@quicinc.com> 1549585415 +0000

[AArch64] Fix condition for "high-vector" DUP optimizations.

AArch64 NEON has a bunch of instructions with a "2" suffix that extract
the top half of the source vectors, instead of the bottom half.  We have
some DAGCombines to try to take advantage of that.  However, they
assumed that any EXTRACT_VECTOR was extracting the high half of the
vector in question.

This issue has apparently existed since the AArch64 backend was merged.

Fixes https://bugs.llvm.org/show_bug.cgi?id=40632 .

Differential Revision: https://reviews.llvm.org/D57862


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353486 91177308-0d34-0410-b5e6-96231b3b80d8