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Re: PATCH: Update sysdeps/x86_64/start.S for x32.
On Mon, May 14, 2012 at 4:28 PM, Roland McGrath <roland@hack.frob.com> wrote:
> Please don't use attachments unless there is really a need.
>
> Your log entry still mentions <sysdep.h> though that's not part of the change.
>
>> > "4-byte"
>>
>> Done.
>
> Here too:
>
> + ? ? ? mov (%rsp), %esi ? ? ? ?/* Simulate popping 4byte argument count. ?*/
> + ? ? ? add $4, %esp
I sent another updated patch in a separate email.
>> > Is it right that x32 uses full 8-byte stack slots for arguments
>> > that are of 4-byte types?
>>
>> X32 kernel interface uses the same ia32 compat layer,
>> which uses 4-byte slot for passing the argument account
>> on stack from kernel to user space.
>
> That's not what I asked. ?I'm talking about the arguments to C functions,
> such as the seventh argument to __libc_start_main.
>
At user level, the minimum argument slot for x32 is 8 bytes,
the same as x86-64.
--
H.J.