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Re: Preserve pointer types in ivopts
On 03/16/2012 02:46 PM, Richard Guenther wrote:
> In the end what we want is a POINTER_PLUS_EXPR variant
> that does not make alias-analysis assume the result still points
> to within the objects the pointer pointed to before the increment/decrement.
Hold on, is alias analysis really affected by this? Sure, we create
temporary pointers that point outside their base object, but we don't
dereference them. Anything value that ends up in a MEM_REF can only
point into that object again.
I would have thought that it's mainly in fold-const where a
POINTER_PLUSV would be handled differently from POINTER_PLUS (e.g. in
pointer comparisons).
Bernd