Re: [PATCH 1/2] Add verification of gimple_assign_nontemporal_move_p [PR112976]

[Richard Biener <richard.guenther@gmail.com>]

On Sat, Apr 27, 2024 at 1:04 AM Andrew Pinski <quic_apinski@quicinc.com> wrote:
>
> Currently the middle-end only knows how to support temporal stores
> (the undocumented storent optab) so let's verify that the only time
> we set nontemporal_move on an assign is if the the lhs is not a
> gimple reg.
>
> Bootstrapped and tested on x86_64-linux-gnu no regressions.

OK.

> gcc/ChangeLog:
>
>         PR middle-end/112976
>         * tree-cfg.cc (verify_gimple_assign): Verify that
>         nontmporal moves are stores.
>         * gimple.h (struct gimple): Note that only
>         nontemporal stores are supported.
>
> Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
> ---
>  gcc/gimple.h    |  3 ++-
>  gcc/tree-cfg.cc | 11 +++++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/gcc/gimple.h b/gcc/gimple.h
> index 8a8ca109bbf..bd315ffc2dd 100644
> --- a/gcc/gimple.h
> +++ b/gcc/gimple.h
> @@ -236,7 +236,8 @@ struct GTY((desc ("gimple_statement_structure (&%h)"), tag ("GSS_BASE"),
>       for clearing this bit before using it.  */
>    unsigned int visited         : 1;
>
> -  /* Nonzero if this tuple represents a non-temporal move.  */
> +  /* Nonzero if this tuple represents a non-temporal move; currently
> +     only stores are supported.  */
>    unsigned int nontemporal_move        : 1;
>
>    /* Pass local flags.  These flags are free for any pass to use as
> diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
> index b1ba33018fd..06a96f96be7 100644
> --- a/gcc/tree-cfg.cc
> +++ b/gcc/tree-cfg.cc
> @@ -4837,6 +4837,17 @@ verify_gimple_assign_single (gassign *stmt)
>  static bool
>  verify_gimple_assign (gassign *stmt)
>  {
> +  if (gimple_assign_nontemporal_move_p (stmt))
> +    {
> +      tree lhs = gimple_assign_lhs (stmt);
> +      if (is_gimple_reg (lhs))
> +       {
> +         error ("nontemporal store lhs cannot a gimple register");
> +         debug_generic_stmt (lhs);
> +         return true;
> +       }
> +    }
> +
>    switch (gimple_assign_rhs_class (stmt))
>      {
>      case GIMPLE_SINGLE_RHS:
> --
> 2.43.0
>