[committed] testsuite: Add a vect_load_lanes guard

[Richard Sandiford via Gcc-patches]

We still fall back to load/store-lanes for slp-46.c, if the target
supports it.

Tested on aarch64-linux-gnu (with and without SVE), arm-linux-gnueabihf
and x86_64-linux-gnu.  Pushed as obvious.

Richard


gcc/testsuite/
        * gcc.dg/vect/slp-46.c: XFAIL test for SLP on vect_load_lanes targets.
---
 gcc/testsuite/gcc.dg/vect/slp-46.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/testsuite/gcc.dg/vect/slp-46.c 
b/gcc/testsuite/gcc.dg/vect/slp-46.c
index 58a238aad6c..18476a43d3f 100644
--- a/gcc/testsuite/gcc.dg/vect/slp-46.c
+++ b/gcc/testsuite/gcc.dg/vect/slp-46.c
@@ -94,4 +94,4 @@ main ()
   return 0;
 }
 
-/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 2 "vect" } 
} */
+/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 2 "vect" { 
xfail vect_load_lanes } } } */