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Re: [PATCH] Fix multiply-add regressions after expand-from-SSA

Hi,

On Thu, 30 Apr 2009, Paolo Bonzini wrote:

> > Actually the helper could look like
> 
> Couldn't this lead to wrong code for
> 
> a_1 = b_1 * c_1;
> b_2 = b_1 + 1.0;
> c_3 = b_2 + a_1;
> 
> where b_1 and b_2 could be assigned to the same partition and so the
> final result would be "b_2 + b_2 * c_1"?

TER already has to handle this case, and as he uses only the TER results 
this should be safe.  IOW: if that would be broken it would have been 
broken since quite some time as TER did exactly the same transformations.
(And yes, TER works with the final partitions to detect that it can move 
definitions forward)


Ciao,
Michael.
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