Re: [PATCH] Fix up vectorizer cost model use of uninitialized value (PR tree-optimization/52210)
On Mon, 13 Feb 2012, Jakub Jelinek wrote:
Hi!
The PR50912 changed vect_get_and_check_slp_defs dt from
array into scalar, which fails when calling vect_model_simple_cost
which looks at two array members. I believe even 4.6 checked just
the first operand, as it called it when processing the first operand,
so IMHO this patch doesn't regress (the very incomplete) cost model
handling and doesn't introduce undefined behavior.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ok.
Thanks,
Richard.
2012-02-13 Jakub Jelinek ja...@redhat.com
PR tree-optimization/52210
* tree-vect-slp.c (vect_get_and_check_slp_defs): Call
vect_model_simple_cost with two entry vect_def_type array instead
of an address of dt.
* gcc.dg/pr52210.c: New test.
--- gcc/tree-vect-slp.c.jj2012-02-07 16:05:51.0 +0100
+++ gcc/tree-vect-slp.c 2012-02-13 10:14:28.017357662 +0100
@@ -321,10 +321,15 @@ vect_get_and_check_slp_defs (loop_vec_in
vect_model_store_cost (stmt_info, ncopies_for_cost, false,
dt, slp_node);
else
- /* Not memory operation (we don't call this function for
-loads). */
- vect_model_simple_cost (stmt_info, ncopies_for_cost, dt,
- slp_node);
+ {
+ enum vect_def_type dts[2];
+ dts[0] = dt;
+ dts[1] = vect_uninitialized_def;
+ /* Not memory operation (we don't call this function for
+ loads). */
+ vect_model_simple_cost (stmt_info, ncopies_for_cost, dts,
+ slp_node);
+ }
}
}
else
--- gcc/testsuite/gcc.dg/pr52210.c.jj 2012-02-13 10:27:46.692809216 +0100
+++ gcc/testsuite/gcc.dg/pr52210.c2012-02-13 10:25:31.0 +0100
@@ -0,0 +1,12 @@
+/* PR tree-optimization/52210 */
+/* { dg-do compile } */
+/* { dg-options -O3 } */
+
+void
+foo (long *x, long y, long z)
+{
+ long a = x[0];
+ long b = x[1];
+ x[0] = a ~y;
+ x[1] = b ~z;
+}
Jakub
--
Richard Guenther rguent...@suse.de
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer
[PATCH] Fix up vectorizer cost model use of uninitialized value (PR tree-optimization/52210)
Hi!
The PR50912 changed vect_get_and_check_slp_defs dt from
array into scalar, which fails when calling vect_model_simple_cost
which looks at two array members. I believe even 4.6 checked just
the first operand, as it called it when processing the first operand,
so IMHO this patch doesn't regress (the very incomplete) cost model
handling and doesn't introduce undefined behavior.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2012-02-13 Jakub Jelinek ja...@redhat.com
PR tree-optimization/52210
* tree-vect-slp.c (vect_get_and_check_slp_defs): Call
vect_model_simple_cost with two entry vect_def_type array instead
of an address of dt.
* gcc.dg/pr52210.c: New test.
--- gcc/tree-vect-slp.c.jj 2012-02-07 16:05:51.0 +0100
+++ gcc/tree-vect-slp.c 2012-02-13 10:14:28.017357662 +0100
@@ -321,10 +321,15 @@ vect_get_and_check_slp_defs (loop_vec_in
vect_model_store_cost (stmt_info, ncopies_for_cost, false,
dt, slp_node);
else
- /* Not memory operation (we don't call this function for
- loads). */
- vect_model_simple_cost (stmt_info, ncopies_for_cost, dt,
- slp_node);
+ {
+ enum vect_def_type dts[2];
+ dts[0] = dt;
+ dts[1] = vect_uninitialized_def;
+ /* Not memory operation (we don't call this function for
+loads). */
+ vect_model_simple_cost (stmt_info, ncopies_for_cost, dts,
+ slp_node);
+ }
}
}
else
--- gcc/testsuite/gcc.dg/pr52210.c.jj 2012-02-13 10:27:46.692809216 +0100
+++ gcc/testsuite/gcc.dg/pr52210.c 2012-02-13 10:25:31.0 +0100
@@ -0,0 +1,12 @@
+/* PR tree-optimization/52210 */
+/* { dg-do compile } */
+/* { dg-options -O3 } */
+
+void
+foo (long *x, long y, long z)
+{
+ long a = x[0];
+ long b = x[1];
+ x[0] = a ~y;
+ x[1] = b ~z;
+}
Jakub
