[PATCH] Fix ICE in vectorizable_store ().

[Kirill Yukhin]

Hello,
Thet patch in the bottom adds check if rhs is "useless_type_conversion_p"
in vectorizable_store () to avoid subsequent gcc_assert.

This change is very similar to [1].

Bootstrapped & regtest in progress.

Is it ok for main trunk if regtest pass?

gcc/
        * tree-vect-stmts.c (vectorizable_store): Check
        rhs vectype.


[1] - https://gcc.gnu.org/ml/gcc-patches/2015-11/msg01551.html

--
Thanks, K

commit 4383b8f528f0b5e2ea3366b51c4c76d29cf7a416
Author: Kirill Yukhin <kirill.yuk...@intel.com>
Date:   Fri Jan 15 14:07:59 2016 +0300

    Fix ICE in vectorizable_store ().

diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c
index 872fa07..7e44601 100644
--- a/gcc/tree-vect-stmts.c
+++ b/gcc/tree-vect-stmts.c
@@ -5282,7 +5282,7 @@ vectorizable_store (gimple *stmt, gimple_stmt_iterator 
*gsi, gimple **vec_stmt,
 
   gcc_assert (gimple_assign_single_p (stmt));
 
-  tree vectype = STMT_VINFO_VECTYPE (stmt_info);
+  tree vectype = STMT_VINFO_VECTYPE (stmt_info), rhs_vectype = NULL_TREE;
   unsigned int nunits = TYPE_VECTOR_SUBPARTS (vectype);
 
   if (loop_vinfo)
@@ -5308,7 +5308,8 @@ vectorizable_store (gimple *stmt, gimple_stmt_iterator 
*gsi, gimple **vec_stmt,
     }
 
   op = gimple_assign_rhs1 (stmt);
-  if (!vect_is_simple_use (op, vinfo, &def_stmt, &dt))
+
+  if (!vect_is_simple_use (op, vinfo, &def_stmt, &dt, &rhs_vectype))
     {
       if (dump_enabled_p ())
         dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
@@ -5316,6 +5317,9 @@ vectorizable_store (gimple *stmt, gimple_stmt_iterator 
*gsi, gimple **vec_stmt,
       return false;
     }
 
+  if (!rhs_vectype || !useless_type_conversion_p (vectype, rhs_vectype))
+      return false;
+
   elem_type = TREE_TYPE (vectype);
   vec_mode = TYPE_MODE (vectype);