tree-optimization/120357 - ICE with early break vectorization

When doing early break vectorization of a loop with a conditional
reduction the epilog creation code is confused as to before which exit
to insert the conditional reduction induction IV update.  The
following make sure this is done before the main IV exit.

	PR tree-optimization/120357
	* tree-vect-loop.cc (vect_create_epilog_for_reduction): Create
	the conditional reduction induction IV increment before the
	main IV exit.

	* gcc.dg/vect/vect-early-break_136-pr120357.c: New testcase.

(cherry picked from commit dce4da51ab66c3abb84448326910cd42f6fe2499)

diff --git a/gcc/testsuite/gcc.dg/vect/vect-early-break_136-pr120357.c b/gcc/testsuite/gcc.dg/vect/vect-early-break_136-pr120357.c
new file mode 100644 (file)
index 0000000..8a51cfc
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/vect-early-break_136-pr120357.c
@@ -0,0 +1,13 @@
+/* { dg-do compile } */
+/* { dg-add-options vect_early_break } */
+/* { dg-additional-options "-O3" } */
+
+char a;
+unsigned long long t[2][22];
+int u[22];
+void f(void)
+{
+  for (int v = 0; v < 22; v++)
+    for (_Bool w = 0; w < (u[v] < 0) + 1; w = 1)
+      a *= 0 != t[w][v];
+}

diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 75fbcdf46d09b3a1e1669abbee57b2fad170ad51..37548d03edb48609d0ed5c9d81d35c72f9aa1c9f 100644 (file)
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -6134,7 +6134,8 @@ vect_create_epilog_for_reduction (loop_vec_info loop_vinfo,
       /* Create an induction variable.  */
       gimple_stmt_iterator incr_gsi;
       bool insert_after;
-      vect_iv_increment_position (loop_exit, &incr_gsi, &insert_after);
+      vect_iv_increment_position (LOOP_VINFO_IV_EXIT (loop_vinfo),
+                                 &incr_gsi, &insert_after);
       create_iv (series_vect, PLUS_EXPR, vec_step, NULL_TREE, loop, &incr_gsi,
                 insert_after, &indx_before_incr, &indx_after_incr);