re PR tree-optimization/69173 (ICE (segfault) in vinfo_for_stmt)

2016-01-11  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/69173
	* tree-vect-loop.c (vect_fixup_scalar_cycles_with_patterns): Only
	fixup the cycle if all stmts are in a pattern.

	* gcc.dg/torture/pr69173.c: New testcase.

From-SVN: r232230

gcc/ChangeLog

+2016-01-11  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69173
+	* tree-vect-loop.c (vect_fixup_scalar_cycles_with_patterns): Only
+	fixup the cycle if all stmts are in a pattern.
+
 2016-01-11  Uros Bizjak  <ubizjak@gmail.com>
 
 	PR middle-end/68999

gcc/testsuite/ChangeLog

+2016-01-11  Richard Biener  <rguenther@suse.de>
+
+	PR tree-optimization/69173
+	* gcc.dg/torture/pr69173.c: New testcase.
+
 2016-01-11  Kyrylo Tkachov  <kyrylo.tkachov@arm.com>
 
 	PR rtl-optimization/68796

gcc/testsuite/gcc.dg/torture/pr69173.c

+/* { dg-do compile } */
+
+unsigned a;
+unsigned *b;
+void fn1() {
+    char c;
+    while (b < (unsigned *)fn1)
+      {
+	a += b[2] + c;
+	b++;
+      }
+}

gcc/tree-vect-loop.c

@@ -985,9 +985,21 @@ vect_fixup_scalar_cycles_with_patterns (loop_vec_info loop_vinfo)
   FOR_EACH_VEC_ELT (LOOP_VINFO_REDUCTION_CHAINS (loop_vinfo), i, first)
     if (STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (first)))
       {
-	vect_fixup_reduc_chain (first);
-	LOOP_VINFO_REDUCTION_CHAINS (loop_vinfo)[i]
-	  = STMT_VINFO_RELATED_STMT (vinfo_for_stmt (first));
+	gimple *next = GROUP_NEXT_ELEMENT (vinfo_for_stmt (first));
+	while (next)
+	  {
+	    if (! STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (next)))
+	      break;
+	    next = GROUP_NEXT_ELEMENT (vinfo_for_stmt (next));
+	  }
+	/* If not all stmt in the chain are patterns try to handle
+	   the chain without patterns.  */
+	if (! next)
+	  {
+	    vect_fixup_reduc_chain (first);
+	    LOOP_VINFO_REDUCTION_CHAINS (loop_vinfo)[i]
+	      = STMT_VINFO_RELATED_STMT (vinfo_for_stmt (first));
+	  }
       }
 }