On Sun, Jul 21, 2024 at 11:15 AM Feng Xue OS
<f...@os.amperecomputing.com> wrote:
>
> The work for RFC
> (https://gcc.gnu.org/pipermail/gcc-patches/2024-July/657860.html)
> involves not a little code change, so I have to separate it into several
> batches
> of patchset. This and the following patches constitute the first batch.
>
> Since pattern statement coexists with normal statements in a way that it is
> not linked into function body, we should not invoke utility procedures that
> depends on def/use graph on pattern statement, such as counting uses of a
> pseudo value defined by a pattern statement. This patch is to fix a bug of
> this type in vect pattern formation.
>
> Thanks,
> Feng
> ---
> gcc/
> * tree-vect-patterns.cc (vect_recog_bitfield_ref_pattern): Only call
> single_imm_use if statement is not generated by pattern recognition.
> ---
> gcc/tree-vect-patterns.cc | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/gcc/tree-vect-patterns.cc b/gcc/tree-vect-patterns.cc
> index 4570c25b664..ca8809e7cfd 100644
> --- a/gcc/tree-vect-patterns.cc
> +++ b/gcc/tree-vect-patterns.cc
> @@ -2700,7 +2700,8 @@ vect_recog_bitfield_ref_pattern (vec_info *vinfo,
> stmt_vec_info stmt_info,
> /* If the only use of the result of this BIT_FIELD_REF + CONVERT is a
> PLUS_EXPR then do the shift last as some targets can combine the shift
> and
> add into a single instruction. */
> - if (lhs && single_imm_use (lhs, &use_p, &use_stmt))
> + if (lhs && !STMT_VINFO_RELATED_STMT (stmt_info)
!is_pattern_stmt_p (stmt_info)
should be clearer
OK with that change.
> + && single_imm_use (lhs, &use_p, &use_stmt))
> {
> if (gimple_code (use_stmt) == GIMPLE_ASSIGN
> && gimple_assign_rhs_code (use_stmt) == PLUS_EXPR)
> --
> 2.17.1
>
