------- Comment #5 from steven at gcc dot gnu dot org 2008-12-04 17:27 ------- by_all was there because you made it so on purpose. From tree-ssa-pre.c:
" For the partial anticipation case, we only perform insertion if it is partially anticipated in some block, and fully available in all of the predecessors. " -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38401
