[Bug tree-optimization/49869] New: Excessive loop versioning done by vectorization + predictive commoning

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49869

           Summary: Excessive loop versioning done by vectorization +
                    predictive commoning
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: rguenth@gcc.gnu.org


SUBROUTINE ANYAVG(NLVLS,HTS,PARRAY,ZBOT,NDXABV,ZTOP,NDXBLW,VALAVG)
      IMPLICIT NONE
      INTEGER I , NLVLS , NDXABV , NDXBLW
      REAL HTS(NLVLS) , PARRAY(NLVLS) , ZBOT , ZTOP , SUM , VALAVG
      REAL VALBOT , VALTOP
      IF ( ZBOT.LT.0.5 ) THEN
         ZBOT = 0.5
         NDXABV = 2
      ENDIF
      IF ( ZTOP.LT.0.51 ) THEN
         ZTOP = 0.51
         NDXBLW = 2
      ENDIF
      IF ( NDXBLW.LE.NDXABV ) GOTO 200
      DO I = NDXABV + 1 , NDXBLW
         SUM = SUM + (HTS(I)-HTS(I-1))*0.5*(PARRAY(I)+PARRAY(I-1))
      ENDDO
 200  CONTINUE
      VALAVG = SUM/(ZTOP-ZBOT)
      END

ends up with 5 loop copies.