http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55912
--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> --- (In reply to Richard Biener from comment #2) > Most of the math builtin folding needs to be re-done at GIMPLE level based > on SSA form. Convenient places are either tree-ssa-forwprop.c or > tree-ssa-math-opts.c (sincos pass which also does power series expansion > now). tree-ssa-reassoc.c seems like a natural place to optimize x*a/x, since it already handles x+a-x.
