[PATCH] D12334: [ARM] Do not use vtrn for vectorshuffle if the order is reversed

[Ahmed Bougacha via llvm-commits]

ab accepted this revision.
ab added a comment.
This revision is now accepted and ready to land.

Nice! We still can't catch <-1, 4, 2, 6> though, right? If so, a FIXME would be enough.

LGTM, thanks!


================
Comment at: test/CodeGen/ARM/vtrn.ll:379
@@ +378,3 @@
+  ; CHECK-LABEL: lower_twice_no_vtrn
+  ; CHECK: @ BB#0:
+  ; CHECK-NOT: vtrn
----------------
No need to check BB#0? (Same below)


http://reviews.llvm.org/D12334