Fully flow and context sensitive points-to analysis in GCC 4.6.0

[Uday P. Khedker]

Andrew Pinski wrote, On Friday 12 October 2012 11:26 AM:


> Except the problem here is just about what f1 clobbers.  Since a has
> not escaped by the time f1 is called, f1 cannot clobber a (or d).
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=23384 for reference on why
> GCC gets this incorrect.  GCC does not have a flow sensitive clobber
> list yet.
>

Agreed. However, two pertinent points are:

- I can replace the call to f1 by some statically indeterminate boolean
   condition that does not involve any function call. So my basic point
   although details could vary.

- It is this flow insensitivity that I dislike :-) I have been trying for
   over five years to do away with flow and context insensitivity without
   hampering efficiency. Now I know that avoiding them could actually aid
   efficiency, apart from the guaranteed benefit of precision :-)

Uday.