Half-baked i386 stack alignment thoughts

[John Wehle]

>On Thu, Nov 02, 2000 at 07:00:39PM -0500, John Wehle wrote:
>> What I propose is making -maccumulate-outgoing-args the default
>> and use push to place the arguments on the stack.  I.e.:
>> 
>>   ...
>>   addl    $8, %esp
>>   pushl   %eax
>>   pushl   %eax
>>   call    subr
>>   movl    %eax, %ebx
>
> It's an interesting idea, though I doubt you'll be able to
> do it with the accumulate-outgoing-args logic.

I'm curious what you mean by that.  What I had in mind was modifying
calls.c so that ACCUMULATE_OUTGOING_ARGS controls if a preallocated
space is used and PUSH_ARGS controls whether move or push instructions
are used.  Currently having ACCUMULATE_OUTGOING_ARGS and PUSH_ARGS
both true is documented as an illegal configuration.

Unfortunately calls.c appears somewhat complex and fragile ...
a combination which may increase the number of iterations required
to get it right.  :-(  However, I'm willing to burn the time if
it seems worthwhile.

-- John
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