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Re: RFC: x86 Linux stack alignment requirement
On Wed, Jun 07, 2006 at 06:43:50PM +0200, Sandro Tolaini wrote:
>
> On 07/giu/2006, at 18:22, H. J. Lu wrote:
>
> >The x86 psABI is very old and doesn't cover XMM registers. I'd like to
> >update x86 Linux calling convention for XMM register usage. I am not
> >sure if I should update stack alignment requirement.
>
> Maybe you'll want to check how this is handled in Darwin/x86, which
> requires 16-byte stack alignment because it is internally using XMM
> registers.
>
They try to support 4byte alignment legacy code with
http://gcc.gnu.org/ml/gcc-patches/2006-05/msg00526.html
There are 2 different, but related questions:
1. Should Linux require gcc generates 16byte aligned stack?
2. How should Linux support 4byte alignment code?
H.J.
H.J.