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Re: [PATCH][C/C++] Do not promote return arguments

On Mon, Aug 27, 2007 at 03:47:02PM +0200, Paolo Bonzini wrote:
> Richard Guenther wrote:
> >On Mon, 27 Aug 2007, Paolo Bonzini wrote:
> >
> >>>I did some investigation and i386 consistently does not set
> >>>TARGET_PROMOTE_FUNCTION_RETURN (that is, it returns QImode for
> >>>char return types from function_value).
> >>That seems wrong.
> >
> >Can you elaborate?
> 
> If the ABI said (I might remember wrong) that they are returned 
> extended, it should return SImode.
> 

See

http://groups.google.com/group/ia32-abi/browse_thread/thread/f47e0106b21d9269

for QImode return value, the upper bits are undefined. We can
do whatever we want and shouldn't cause any problems.

H.J.
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