alias analysis

[Jim Wilson]

Umar Janjua wrote:
> What kind of alias analysis is performed by GCC.

Current gcc sources do ad-hoc alias analysis.  We do some tests based on 
type info, using C rules for aliasing of types.  We do some tests based 
on where an object lives, e.g. stack addresses can't alias heap address. 
  We check the actual pointer values if we have them.  Etc.  See the 
code in alias.c.

On the tree-ssa branch there is quite a bit more, for instance, an 
implementation of Andersen's points-to analysis.
-- 
Jim Wilson, GNU Tools Support, http://www.SpecifixInc.com