[gcc r13-2494] tree-ssa-forwprop.cc: Adjust res_type when operands have differing vector lengths.

[gcc r13-2494] tree-ssa-forwprop.cc: Adjust res_type when operands have differing vector lengths.

[Prathamesh Kulkarni]

https://gcc.gnu.org/g:e55674b86a10e695cea2f45c0472402b97cc2dfb

commit r13-2494-ge55674b86a10e695cea2f45c0472402b97cc2dfb
Author: Prathamesh Kulkarni <prathamesh.kulkarni@linaro.org>
Date:   Tue Sep 6 15:18:04 2022 +0530

    tree-ssa-forwprop.cc: Adjust res_type when operands have differing vector lengths.
    
    gcc/
            * tree-ssa-forwprop.cc (simplify_permutation): Set res_type to a vector
            type with same element type as arg0, and length as op2.

Diff:
---
 gcc/tree-ssa-forwprop.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/gcc/tree-ssa-forwprop.cc b/gcc/tree-ssa-forwprop.cc
index fdc4bc8909d..4b693ef095c 100644
--- a/gcc/tree-ssa-forwprop.cc
+++ b/gcc/tree-ssa-forwprop.cc
@@ -2661,7 +2661,9 @@ simplify_permutation (gimple_stmt_iterator *gsi)
 
       /* Shuffle of a constructor.  */
       bool ret = false;
-      tree res_type = TREE_TYPE (arg0);
+      tree res_type
+	= build_vector_type (TREE_TYPE (TREE_TYPE (arg0)),
+			     TYPE_VECTOR_SUBPARTS (TREE_TYPE (op2)));
       tree opt = fold_ternary (VEC_PERM_EXPR, res_type, arg0, arg1, op2);
       if (!opt
 	  || (TREE_CODE (opt) != CONSTRUCTOR && TREE_CODE (opt) != VECTOR_CST))