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Re: va-arg-25.c still fails on i686-linux



On 12/01/2004, at 4:37 PM, Jan Hubicka wrote:


Jan Hubicka <hubicka@ucw.cz> writes:


On 09/01/2004, at 11:06 PM, Zack Weinberg wrote:



I am still seeing va-arg-25.c fail at all optimization levels on i686-linux. It has done so, as far as I can tell, ever since it was introduced. Could you please either fix it or XFAIL it?

I think it would be better if an x86 port maintainer looked at this
failure.  The testcase does not fail on powerpc-Darwin.

It don't even need x86 port maintainer :)
The problem is wrong aligning of va_arg inside builtins.c when argument
alignment exceeds PARM_BOUNDARY.


Additionally I noticed some problems with SSE enabled (we mistakely used
SSE regiser for variadic call and output warning)


Note that I am not quite sure about the PAD_VARARGS_DOWN check, it just
seems appropriate at that place.


Bootstrapping/regtesting in progress, OK if it passes?

The concept looks good but I am nervous about a change in machine-independent code. Can you arrange testing on a few more architectures? (especially ones with complicated rules about arguments being passed in registers - ia64 comes to mind).

Every architecture passing arguments in registers use it's own va_arg expander (see ia64_va_arg). This code triggers only in quite specific case of architecture having no register passing convention but still requiring larger alignment than word for some operands. I know only of i386 being such a crazy creature.

ppc does this, in fact that was the motivation for this testcase.



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