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Re: ping [RFC] [patch] fix PR32893 - forcing alignment >= STACK_BOUNDARY
On Mon, Oct 22, 2007 at 12:39:39PM -0500, Mark Mitchell wrote:
> For GCC 4.3, I don't think you have a choice: you need to change the
> vectorized to use plain STACK_BOUNDARY, because that's all the compiler
> can actually support. I understand the performance cost, but
> correctness has to trump performance. ABIs designed to support vector
> instructions will probably ensure that STACK_BOUNDARY is large enough
> that this is not an issue.
FYI, as I learned recently, powerpc-linux is one target where
STACK_BOUNDARY is smaller than PREFERRED_STACK_BOUNDARY - but
in fact GCC and the ABI always arrange for the larger alignment.
So a new macro may be called for to continue taking advantage of
AltiVec in the vectorizer.
--
Daniel Jacobowitz
CodeSourcery