Re: [PATCH] x86: Always update EH return address in word_mode

[Uros Bizjak <ubizjak at gmail dot com>]

On Mon, Aug 20, 2018 at 8:19 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
> On x86, return address is always popped in word_mode.  eh_return needs
> to put EH return address in word_mode on stack.
>
> Tested on x86-64 with x32. OK for trunk and release branches?

OK. Perhaps the testcase should go into g++.dg/torture, since it is
sensitive to optimization level?

Thanks,
Uros.

> Thanks.
>
> H.J.
> ---
> gcc/
>
>         PR target/87014
>         * config/i386/i386.md (eh_return): Always update EH return
>         address in word_mode.
>
> gcc/testsuite/
>
>         PR target/87014
>         * g++.dg/pr87014.C: New file.
> ---
>  gcc/config/i386/i386.md        |  5 ++++-
>  gcc/testsuite/g++.dg/pr87014.C | 38 ++++++++++++++++++++++++++++++++++
>  2 files changed, 42 insertions(+), 1 deletion(-)
>  create mode 100644 gcc/testsuite/g++.dg/pr87014.C
>
> diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
> index 918241d953a..71faa218ffa 100644
> --- a/gcc/config/i386/i386.md
> +++ b/gcc/config/i386/i386.md
> @@ -13612,7 +13612,10 @@
>       stack address we wish to restore.  */
>    tmp = gen_rtx_PLUS (Pmode, arg_pointer_rtx, sa);
>    tmp = plus_constant (Pmode, tmp, -UNITS_PER_WORD);
> -  tmp = gen_rtx_MEM (Pmode, tmp);
> +  /* Return address is always in word_mode.  */
> +  tmp = gen_rtx_MEM (word_mode, tmp);
> +  if (GET_MODE (ra) != word_mode)
> +    ra = convert_to_mode (word_mode, ra, 1);
>    emit_move_insn (tmp, ra);
>
>    emit_jump_insn (gen_eh_return_internal ());
> diff --git a/gcc/testsuite/g++.dg/pr87014.C b/gcc/testsuite/g++.dg/pr87014.C
> new file mode 100644
> index 00000000000..060ec948c90
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/pr87014.C
> @@ -0,0 +1,38 @@
> +// { dg-do run }
> +// { dg-options "-O0" }
> +
> +void
> +fillstack ()
> +{
> +  long long foo[] =
> +    {
> +      -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
> +    };
> +}
> +
> +void
> +f (long long=-1,long long=-1,long long=-1,long long=-1,
> +   long long=-1,long long=-1,long long arg7_on_stack=-1)
> +{
> +  throw 0;
> +}
> +
> +void
> +g()
> +{
> +  try
> +    {
> +      f ();
> +    }
> +  catch (int)
> +    {
> +    }
> +}
> +
> +int
> +main()
> +{
> +  fillstack ();
> +  g ();
> +  return 0;
> +}
> --
> 2.17.1
>