Hi!
The following testcase ICEs, because BIT_FIELD_REF's position is not
multiple of the vector element's bit size and the code uses exact_div
to divide those 2 values.
For BIT_INSERT_EXPR, the tree-cfg.cc verification verifies the position
is a multiple of the inserted bit size when inserting into vectors,
but for BIT_FIELD_REF the position can be arbitrary if within the range.
The following patch fixes that, bootstrapped/regtested on x86_64-linux and
i686-linux, ok for trunk?
2024-02-19 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/113967
* match.pd (bit_insert @0 (BIT_FIELD_REF @1 ..) ..): Require
in condition that @rpos is multiple of vector element size.
* gcc.dg/pr113967.c: New test.
--- gcc/match.pd.jj 2024-02-01 09:14:16.541550659 +0100
+++ gcc/match.pd 2024-02-17 11:58:19.822913858 +0100
@@ -8586,7 +8586,9 @@ (define_operator_list SYNC_FETCH_AND_AND
|| optimize_vectors_before_lowering_p ())
&& types_match (@0, @1)
&& types_match (TREE_TYPE (TREE_TYPE (@0)), TREE_TYPE (@2))
- && TYPE_VECTOR_SUBPARTS (type).is_constant ())
+ && TYPE_VECTOR_SUBPARTS (type).is_constant ()
+ && multiple_p (wi::to_poly_offset (@rpos),
+ wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (type)))))
(with
{
unsigned HOST_WIDE_INT elsz
--- gcc/testsuite/gcc.dg/pr113967.c.jj 2024-02-17 12:01:06.784623682 +0100
+++ gcc/testsuite/gcc.dg/pr113967.c 2024-02-17 12:00:19.384273862 +0100
@@ -0,0 +1,14 @@
+/* PR tree-optimization/113967 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+
+typedef unsigned short W __attribute__((vector_size (4 * sizeof (short))));
+
+void
+foo (W *p)
+{
+ W x = *p;
+ W y = {};
+ __builtin_memcpy (&y, 1 + (char *) &x, sizeof (short));
+ *p = y;
+}
Jakub
