Re: patch to fix PR57559 for s390

[Vladimir Makarov <vmakarov@redhat.com>]

On 13-06-19 2:31 PM, Richard Sandiford wrote:
> Richard Sandiford <rdsandiford@googlemail.com> writes:
>> Vladimir Makarov <vmakarov@redhat.com> writes:
>>> Index: lra.c
>>> ===================================================================
>>> --- lra.c	(revision 199753)
>>> +++ lra.c	(working copy)
>>> @@ -306,11 +306,11 @@ lra_emit_add (rtx x, rtx y, rtx z)
>>>   	  || (disp != NULL_RTX && ! CONSTANT_P (disp))
>>>   	  || (scale != NULL_RTX && ! CONSTANT_P (scale)))
>>>   	{
>>> -	  /* Its is not an address generation.	Probably we have no 3 op
>>> +	  /* It is not an address generation.	Probably we have no 3 op
>>>   	     add.  Last chance is to use 2-op add insn.	 */
>>>   	  lra_assert (x != y && x != z);
>>> -	  emit_move_insn (x, z);
>>> -	  insn = gen_add2_insn (x, y);
>>> +	  emit_move_insn (x, y);
>>> +	  insn = gen_add2_insn (x, z);
>>>   	  emit_insn (insn);
>>>   	}
>>>         else
>> Could you add a comment to lra_emit_add saying why it has to be this
>> way round (move y, add z)?
> Ping.
I am going to add a comment when I submit my next patch (it will happen 
today or tomorrow).  The reason is simple as address segment is stored 
in y not in z and generation of addition of address segment to pseudo 
can fail (that is what happens for the PR).


Thanks, Richard.