------- Comment #20 from dberlin at gcc dot gnu dot org 2008-02-16 14:56 ------- Subject: Re: [4.3 Regression] crash by too deep recursion in DFS tree-ssa-sccvn.c:1898
So, there are better SCC algorithms. In particular, Nuutilla's algorithm will avoid placing a bunch of nodes on the stack (pearce's is a modification of this). This is what structalias uses. You can also certainly make the algorithm non-recursive, but it is a bunch of work. See http://www.cise.ufl.edu/research/sparse/btf/BTF/Source/btf_strongcomp.c for an example of a non-recursive SCC finder. In essence, you have to keep stacks for each variable. On 16 Feb 2008 12:51:44 -0000, rguenth at gcc dot gnu dot org <[EMAIL PROTECTED]> wrote: > > > ------- Comment #19 from rguenth at gcc dot gnu dot org 2008-02-16 12:51 > ------- > Note that while it definitely improves stack usage, the total memory usage is > likely to go up (vectors allocate some extra heap, the iters are now > addressable > and thus consume full memory) and as the ssa_op_iter is now pinned to memory > it is likely the algorithm is slower as well. > > > -- > > > > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35204 > > ------- You are receiving this mail because: ------- > You are on the CC list for the bug, or are watching someone who is. > -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35204