From: Richard Biener <rguenther@suse.de>
Date: Mon, 20 Feb 2023 09:59:15 +0000 (+0100)
Subject: tree-optimization/108816 - vect versioning check split confusion
X-Git-Tag: basepoints/gcc-14~1067
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=63471c5008819bbf6ec32a6f4d8701fe57b96fa9;p=thirdparty%2Fgcc.git

tree-optimization/108816 - vect versioning check split confusion

The split of the versioning condition assumes the definition is
in the condition block which is ensured by the versioning code.
But that only works when we actually have to insert any statements
for the versioning condition.  The following adjusts the guard
accordingly and asserts this condition.

	PR tree-optimization/108816
	* tree-vect-loop-manip.cc (vect_loop_versioning): Adjust
	versioning condition split prerequesite, assert required
	invariant.

	* gcc.dg/torture/pr108816.c: New testcase.
---

diff --git a/gcc/testsuite/gcc.dg/torture/pr108816.c b/gcc/testsuite/gcc.dg/torture/pr108816.c
new file mode 100644
index 000000000000..4c24d5584c18
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr108816.c
@@ -0,0 +1,18 @@
+/* { dg-do compile } */
+/* { dg-additional-options "-fvect-cost-model=dynamic" } */
+
+int m;
+
+void
+foo (int p[][16], unsigned int x)
+{
+  while (x < 4)
+    {
+      int j;
+
+      for (j = x * 4; j < (x + 1) * 4 - 2; j++)
+        p[0][j] = p[m][j];
+
+      ++x;
+    }
+}
diff --git a/gcc/tree-vect-loop-manip.cc b/gcc/tree-vect-loop-manip.cc
index c04fcf40c44e..6aa3d2ed0bf8 100644
--- a/gcc/tree-vect-loop-manip.cc
+++ b/gcc/tree-vect-loop-manip.cc
@@ -3477,7 +3477,7 @@ vect_loop_versioning (loop_vec_info loop_vinfo,
   tree cost_name = NULL_TREE;
   profile_probability prob2 = profile_probability::uninitialized ();
   if (cond_expr
-      && !integer_truep (cond_expr)
+      && EXPR_P (cond_expr)
       && (version_niter
 	  || version_align
 	  || version_alias
@@ -3711,6 +3711,7 @@ vect_loop_versioning (loop_vec_info loop_vinfo,
   if (cost_name && TREE_CODE (cost_name) == SSA_NAME)
     {
       gimple *def = SSA_NAME_DEF_STMT (cost_name);
+      gcc_assert (gimple_bb (def) == condition_bb);
       /* All uses of the cost check are 'true' after the check we
 	 are going to insert.  */
       replace_uses_by (cost_name, boolean_true_node);