Add code between for loops

Hi All: I start to study TVM recently, and we offen use the compute as the following:

 ... ...
    rc = tvm.reduce_axis((0, in_channel), name='rc') 
    ry = tvm.reduce_axis((0, kernel), name='ry')
    rx = tvm.reduce_axis((0, kernel), name='rx')
    # Compute the convolution
    B = tvm.compute(
        (out_size, out_size, out_channel, batch),
        lambda yy, xx, ff, nn: tvm.sum(
            A[yy * stride + ry, xx * stride + rx, rc, nn] * W[ry, rx, rc, ff],
            axis=[ry, rx, rc]),
        name='B')

    s = tvm.create_schedule(B.op)

    print(tvm.lower(s,[A,W], simple_mode=True))

And we got some code like:

// attr [B] storage_scope = "global"
allocate B[float32 * 25690112]
produce B {
  for (yy, 0, 14) {
    for (xx, 0, 14) {
      for (ff, 0, 512) {
        for (nn, 0, 256) {
          B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] = 0f
          for (ry, 0, 3) {
            for (rx, 0, 3) {
              for (rc, 0, 256) {
                B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] = (B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] + (A[((((((yy*917504) + (ry*917504)) + (xx*65536)) + (rx*65536)) + (rc*256)) + nn)]*W[((((ry*393216) + (rx*131072)) + (rc*512)) + ff)]))
              }
            }
          }
        }
      }
    }
  }
}

And my question is if I want to add some expression between the for loop, and the pseudocode such as:


... ...
  for (yy, 0, 14) {
    for (xx, 0, 14) {
      for (ff, 0, 512) {       
        for (nn, 0, 256) {
          B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] = 0f
          for (ry, 0, 3) {
            for (rx, 0, 3) {
              for (rc, 0, 256) {
                B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] = (B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)] + (A[((((((yy*917504) + (ry*917504)) + (xx*65536)) + (rx*65536)) + (rc*256)) + nn)]*W[((((ry*393216) + (rx*131072)) + (rc*512)) + ff)]))
              }
            }            
          }
          B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)]  = tvm.if_else_then(B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)]>0, B[((((yy*1835008) + (xx*131072)) + (ff*256)) + nn)], 0.0)
        }
      }
    }
  }
}

How can I realize it? Could any one give me an example? Thanks a lot.