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Re: [tree-ssa] patch suggestion: def_op vs vdef_ops


On Wed, 29 Jan 2003, Jose Renau wrote:

>  I want to do store elimination. It is possible to remove a store when
> between two stores to the same destination address (must-alias) and the
> uses of the instructions between are not aliased to the first store. In
> that case, the first store can be removed and changed to a temporal
> variable (not a memory op).
> 
Unfortunately you cannot do that now as we do not have must-alias
information.  You would only be able to do store elimination if
the variables are not aliased.  In which case, dead stores will
be zapped by DCE.  But I have the impression that I'm not
following you.  Is this what you mean?

	x = k;	<-- dead store to x.
	...
	x = y;
	...
	z = x + k;


Diego.


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