[Bug tree-optimization/55684] [4.8 Regression] ICE in remove_redundant_iv_tests, at tree-ssa-loop-ivcanon.c:559

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55684



Richard Biener <rguenth at gcc dot gnu.org> changed:



           What    |Removed                     |Added

----------------------------------------------------------------------------

             Status|NEW                         |ASSIGNED

                 CC|                            |hubicka at gcc dot gnu.org

         AssignedTo|unassigned at gcc dot       |rguenth at gcc dot gnu.org

                   |gnu.org                     |



--- Comment #4 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-14 
11:50:23 UTC ---

ICEing here is of course pointless.  Looks like a debugging leftover to me.



First when in estimate_numbers_of_iterations_loop, number_of_iterations_exit

succeeds, then in find_loop_niter called from

canonicalize_loop_induction_variables it fails, so does it when called

from remove_redundant_iv_tests for that loop.



So it's quite by design that this can happen.  Testing the obvious patch.