middle-end: Fix ICE in poly-int.h due to SLP.

Adds a check to ensure that the input vector arguments
to a function are not variable length. Previously, only the
output vector of a function was checked.

The ICE in question is within the neon-sve-bridge.c test,
and is related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111268

gcc/ChangeLog:
	PR tree-optimization/111268
	* tree-vect-slp.cc (vectorizable_slp_permutation_1):
	Add variable-length check for vector input arguments
	to a function.

(cherry picked from commit 4571b4d413a4ba5f1e2d429a2623180ad1c73c0f)

diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 570edf38ca4097333a8192bc57c436655466b735..bbc05fac65ece87c4f0d445029a35facfe81883c 100644 (file)
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -8574,7 +8574,8 @@ vectorizable_slp_permutation_1 (vec_info *vinfo, gimple_stmt_iterator *gsi,
     {
       /* Calculate every element of every permute mask vector explicitly,
         instead of relying on the pattern described above.  */
-      if (!nunits.is_constant (&npatterns))
+      if (!nunits.is_constant (&npatterns)
+         || !TYPE_VECTOR_SUBPARTS (op_vectype).is_constant ())
        return -1;
       nelts_per_pattern = ncopies = 1;
       if (loop_vec_info linfo = dyn_cast <loop_vec_info> (vinfo))