------- Comment #22 from rakdver at gcc dot gnu dot org 2009-02-18 04:47 ------- (In reply to comment #21) > Subject: Re: loop number of iterations analysis not working > > > If the program terminates before i would wrap, then the number of > > iterations was not MAXINT. > > And since it can't wrap, it is not infinite in any case. > > > > I agree you can't prove the number of iterations (since bar could > > exit), but the requiring the assumption i != MAXINT still seems > > useless. > > What do you propose that the number of iterations analysis should > return, then?
actually, scratch that. You can redefine the semantics of what number of iterations analysis returns to make i1 a correct answer, while still keeping it safe to use for optimizations: "number_of_iterations_exit (EXIT) returns an expression N such that you don't change the semantics of the program by replacing the condition for taking EXIT with [0,+,1] == N" Now I just need to figure out how to make it work this way without completely rewriting the whole analysis. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26939
