[Bug tree-optimization/43627] [4.5 Regression] slow compilation (tree canonical iv takes 75%)

[rguenth at gcc dot gnu dot org]

------- Comment #13 from rguenth at gcc dot gnu dot org  2010-04-02 14:23 -------
Testcase for that:

MODULE hfx_compression_core_methods

  IMPLICIT NONE

  INTEGER, PARAMETER :: int_8=8

  CONTAINS

  SUBROUTINE ints2bits_3(Ndata,packed_data,full_data)
    INTEGER, INTENT(IN)                      :: Ndata
    INTEGER(KIND=int_8), INTENT(OUT)         :: packed_data(*)
    INTEGER(KIND=int_8), INTENT(IN)          :: full_data(*)

    INTEGER, PARAMETER                       :: Nbits = 3

    INTEGER                                  :: idata, ipack, kdata, Ndata_rep
    INTEGER(KIND=int_8)                      :: data_tmp, pack_tmp

   idata=0
   ipack=0
   Ndata_rep=(Ndata/2)*2
   DO kdata=1,Ndata_rep,2
   pack_tmp=0
     idata=idata+1
        data_tmp = full_data(idata)
        data_tmp = ISHFT(data_tmp,61)
        pack_tmp = IOR(pack_tmp,data_tmp)
        pack_tmp = ISHFT(pack_tmp,-3)
     idata=idata+1
        data_tmp = full_data(idata)
        data_tmp = ISHFT(data_tmp,61)
        pack_tmp = IOR(pack_tmp,data_tmp)
        pack_tmp = ISHFT(pack_tmp,0)
   pack_tmp = ISHFT(pack_tmp,0)
   ipack = ipack + 1
   packed_data(ipack) = pack_tmp
   ENDDO
  END SUBROUTINE ints2bits_3

END MODULE hfx_compression_core_methods


likely caused by

2010-02-16  Richard Guenther  <rguenther@suse.de>

        PR tree-optimization/41043
        * tree-vrp.c  (vrp_var_may_overflow): Only ask SCEV for real loops.
        (vrp_visit_assignment_or_call): Do not ask SCEV for regular
        statements ...
        (vrp_visit_phi_node): ... but only for loop PHI nodes.


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2010-04-02 10:25:15         |2010-04-02 14:23:22
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43627