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Re: Writing over [SP]

> From: Diego Novillo <>

> To: Jamie Prescott <>
> Cc:
> Sent: Friday, May 15, 2009 2:44:23 PM
> Subject: Re: Writing over [SP]
> On Thu, May 14, 2009 at 18:18, Jamie Prescott wrote:
> >
> > This is driving me crazy. Any memory op that tries to write over [SP] get's 
> automatically nuked
> > by the compiler.
> > Any offset, positive or negative, from SP, has no problems.
> > What did I do wrong this time?
> You need to provide a *whole* lot more information if you want us to
> be able to help you.  Input program, compile flags, changes you've
> made to the compiler...

I made no changes on GCC out of my TARGET domain.
An instruction like this one:

insn = gen_move_insn(gen_rtx_MEM(SImode,
                                     gen_rtx_REG(SImode, reg));

Does not emit anything if "offset" == 0, while works for every offset != 0.
Instructions are just discarded.
Will investigate deeper on this as soon as I completed the port to 4.4, that is
currently giving me some headache.

- Jamie


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