[PATCH] PR target/81313: Use DRAP only if there are outgoing arguments on stack

[Uros Bizjak]

On Fri, Jul 7, 2017 at 12:14 AM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Thu, Jul 6, 2017 at 12:08 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
>> Since DRAP is needed only if there are outgoing arguments on stack, we
>> should track outgoing arguments on stack and avoid setting need_drap to
>> true when there are no outgoing arguments on stack.
>>
>> Tested on i686 and x86-64 with SSE2, AVX and AVX2.  There is no
>> regression.  OK for trunk?
>>
>> H.J.
>> ---
>> gcc/
>>
>>         PR target/81313
>>         * config/i386/i386.c (ix86_function_arg_advance): Set
>>         outgoing_args_on_stack to true if there are outgoing arguments
>>         on stack.
>>         (ix86_function_arg): Likewise.
>>         (ix86_get_drap_rtx): Use DRAP only if there are outgoing
>>         arguments on stack and ACCUMULATE_OUTGOING_ARGS is false.
>>         * config/i386/i386.h (machine_function): Add
>>         outgoing_args_on_stack.
>>
>> @@ -10473,6 +10479,10 @@ ix86_function_arg (cumulative_args_t cum_v, machine_mode omode,
>>    else
>>      arg = function_arg_32 (cum, mode, omode, type, bytes, words);
>>
>> +  /* Track if there are outgoing arguments on stack.  */
>> +  if (arg == NULL_RTX)
>> +    cfun->machine->outgoing_args_on_stack = true;
>
> This should be
>
> +  /* Track if there are outgoing arguments on stack.  */
> +  if (arg == NULL_RTX && cum->caller)
> +    cfun->machine->outgoing_args_on_stack = true;
>
> to check outgoing arguments for caller here.
>
>>    return arg;
>>  }
>>
>>
>
> I am testing updated patch with a new testcase.

Updated patch LGTM.

OK for mainline.

Thanks,
Uros.