[Bug middle-end/71898] New: [7 Regression] [graphite] ICE: verify_ssa failed

["Joost.VandeVondele at mat dot ethz.ch" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71898

            Bug ID: 71898
           Summary: [7 Regression] [graphite] ICE: verify_ssa failed
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: Joost.VandeVondele at mat dot ethz.ch
  Target Milestone: ---

The following started regressing roughly July 7th/8th:

> cat bug.f90
MODULE d3_poly
    INTEGER, PUBLIC, PARAMETER :: max_grad2=5
    INTEGER, PUBLIC, PARAMETER :: max_grad3=3
    INTEGER, PUBLIC, PARAMETER :: cached_dim2=(max_grad2+1)*(max_grad2+2)/2
    INTEGER, PUBLIC, PARAMETER ::
cached_dim3=(max_grad3+1)*(max_grad3+2)*(max_grad3+3)/6
    INTEGER, SAVE, DIMENSION(3,cached_dim3) :: a_mono_exp3
    INTEGER, SAVE, DIMENSION(cached_dim2,cached_dim2) :: a_mono_mult2
    INTEGER, SAVE, DIMENSION(cached_dim3,cached_dim3) :: a_mono_mult3
    INTEGER, SAVE, DIMENSION(4,cached_dim3) :: a_mono_mult3a
CONTAINS
SUBROUTINE init_d3_poly_module()
    INTEGER                                  :: grad, i, ii, ij, j, subG
    INTEGER, DIMENSION(3)                    :: monoRes3
    DO grad=0,max_grad2
        DO i=grad,0,-1
            DO j=grad-i,0,-1
            END DO
        END DO
    END DO
    DO ii=1,cached_dim3
        DO ij=ii,cached_dim2
            a_mono_mult2(ij,ii)=a_mono_mult2(ii,ij)
        END DO
    END DO
    DO ii=1,cached_dim3
        DO ij=ii,cached_dim3
            monoRes3=a_mono_exp3(:,ii)+a_mono_exp3(:,ij)
           
a_mono_mult3(ii,ij)=mono_index3(monoRes3(1),monoRes3(2),monoRes3(3))+1
            a_mono_mult3(ij,ii)=a_mono_mult3(ii,ij)
        END DO
    END DO
    DO i=1,cached_dim3
       DO j=1,4
          a_mono_mult3a(j,i)=a_mono_mult3(j,i)
       END DO
    END DO
END SUBROUTINE
PURE FUNCTION mono_index3(i,j,k) RESULT(res)
    INTEGER, INTENT(in)                      :: i, j, k
    res=grad*(grad+1)*(grad+2)/6+(sgrad)*(sgrad+1)/2+k
END FUNCTION
END MODULE d3_poly

> gfortran -c -floop-nest-optimize -O1 bug.f90
bug.f90:11:0:

 SUBROUTINE init_d3_poly_module()

Error: definition in block 74 follows the use
for SSA_NAME: _56 in statement:
_104 = _56 + graphite_IV.7_99;
bug.f90:11:0: internal compiler error: verify_ssa failed
0xdd4efc verify_ssa(bool, bool)
        ../../gcc/gcc/tree-ssa.c:1039
0xd24a41 verify_loop_closed_ssa(bool)
        ../../gcc/gcc/tree-ssa-loop-manip.c:736
0x131afa9 checking_verify_loop_closed_ssa
        ../../gcc/gcc/tree-ssa-loop-manip.h:35
0x131afa9 graphite_verify
        ../../gcc/gcc/graphite-isl-ast-to-gimple.c:98
0x131afa9 graphite_regenerate_ast_isl(scop*)
        ../../gcc/gcc/graphite-isl-ast-to-gimple.c:3205
0x13124c3 graphite_transform_loops()
        ../../gcc/gcc/graphite.c:329
0x1312990 graphite_transforms
        ../../gcc/gcc/graphite.c:356
0x1312990 execute
        ../../gcc/gcc/graphite.c:433
Please submit a full bug report,