re PR tree-optimization/58497 (SLP vectorizes identical operations)

2015-11-12  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/58497
	* tree-vect-generic.c: Include gimplify.h.
	(tree_vec_extract): Lookup constant/constructor DEFs.
	(do_cond): Unshare cond.

From-SVN: r230216

gcc/ChangeLog

+2015-11-12  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/58497
+	* tree-vect-generic.c: Include gimplify.h.
+	(tree_vec_extract): Lookup constant/constructor DEFs.
+	(do_cond): Unshare cond.
+
 2015-11-12  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.c (ix86_legitimate_combined_insn): Reject

gcc/tree-vect-generic.c

@@ -35,6 +35,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-eh.h"
 #include "gimple-iterator.h"
 #include "gimplify-me.h"
+#include "gimplify.h"
 #include "tree-cfg.h"
 
 
@@ -105,6 +106,15 @@ static inline tree
 tree_vec_extract (gimple_stmt_iterator *gsi, tree type,
 		  tree t, tree bitsize, tree bitpos)
 {
+  if (TREE_CODE (t) == SSA_NAME)
+    {
+      gimple *def_stmt = SSA_NAME_DEF_STMT (t);
+      if (is_gimple_assign (def_stmt)
+	  && (gimple_assign_rhs_code (def_stmt) == VECTOR_CST
+	      || (bitpos
+		  && gimple_assign_rhs_code (def_stmt) == CONSTRUCTOR)))
+	t = gimple_assign_rhs1 (def_stmt);
+    }
   if (bitpos)
     {
       if (TREE_CODE (type) == BOOLEAN_TYPE)
@@ -1419,7 +1429,7 @@ do_cond (gimple_stmt_iterator *gsi, tree inner_type, tree a, tree b,
   if (TREE_CODE (TREE_TYPE (b)) == VECTOR_TYPE)
     b = tree_vec_extract (gsi, inner_type, b, bitsize, bitpos);
   tree cond = gimple_assign_rhs1 (gsi_stmt (*gsi));
-  return gimplify_build3 (gsi, code, inner_type, cond, a, b);
+  return gimplify_build3 (gsi, code, inner_type, unshare_expr (cond), a, b);
 }
 
 /* Expand a vector COND_EXPR to scalars, piecewise.  */