1! 2! 3! Fortran kernel for sparse matrix-vector product in the AIJ matrix format 4! 5#include <petsc/finclude/petscsys.h> 6! 7pure subroutine FortranMultTransposeAddAIJ(n, x, ii, jj, a, y) 8 use, intrinsic :: ISO_C_binding 9 implicit none(type, external) 10 PetscScalar, intent(in) :: x(0:*), a(0:*) 11 PetscScalar, intent(inout) :: y(0:*) 12 PetscInt, intent(in) :: n, ii(*), jj(0:*) 13 14 PetscInt :: i, jstart, jend 15 16 jend = ii(1) 17 do i = 1, n 18 jstart = jend 19 jend = ii(i + 1) 20 y(jj(jstart:jend - 1)) = y(jj(jstart:jend - 1)) + x(i - 1)*a(jstart:jend - 1) 21 end do 22end subroutine FortranMultTransposeAddAIJ 23 24pure subroutine FortranMultAIJ(n, x, ii, jj, a, y) 25 use, intrinsic :: ISO_C_binding 26 implicit none(type, external) 27 PetscScalar, intent(in) :: x(0:*), a(0:*) 28 PetscScalar, intent(inout) :: y(*) 29 PetscInt, intent(in) :: n, ii(*), jj(0:*) 30 31 PetscInt :: i, jstart, jend 32 33#ifdef PETSC_USE_OPENMP_KERNELS 34 !omp parallel do private(jstart,jend) 35#endif 36 do i = 1, n 37 jstart = ii(i) 38 jend = ii(i + 1) 39 y(i) = sum(a(jstart:jend - 1)*x(jj(jstart:jend - 1))) 40 end do 41end subroutine FortranMultAIJ 42