------- Additional Comments From dberlin at gcc dot gnu dot org 2005-01-24 23:12 ------- Subject: Re: [4.0 Regression] IV-OPTS is O(N^3)
On Mon, 24 Jan 2005, rakdver at atrey dot karlin dot mff dot cuni dot cz wrote: > > ------- Additional Comments From rakdver at atrey dot karlin dot mff dot cuni > dot cz 2005-01-24 23:09 ------- > Subject: Re: [4.0 Regression] IV-OPTS is O(N^3) > >>> Other part is that scev tries to be too clever. Without need to >>> represent nonaffine induction variables (that we do not use anywhere) >>> we could use more memory efficient representation of ivs. >>> Without need to handle symbolic references (that we also do not use >>> anywhere, we could store evolutions in a fully instantiated form, and >>> we would not need instantiate_parameters/resolve_mixers functions atall. >> >> Uh, symbolic references are or will be used to do data dependence when >> MEM_REF and ARRAY_REF couldn't be generated from the pointers. > > How? If the reference is left in symbolic form, it means that you know > nothing about its value, Wrong. We could know things about it's value, such as ranges. We just don't know an exact number. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18595
