Loopy's host-side shape inference cannot solve system of equations

[kaushikcfd]

knl = lp.make_kernel(
        "{[i, j]: 0<=i<(2*n + 3*m + 2) and 0<=j<(6*n + 4*m + 3)}",
        """
        out = sum([i, j], A[i, j])
        """)

knl(cq, A=np.random.randn(20, 37))

fails with

  File "<generated code>", line 52, in invoke_loopy_kernel_loopy_kernel
TypeError: value argument 'm' was not given and could not be automatically determined

Loopy couldn't infer that n=3, m=4 corresponds from A's shape.

[inducer]

As far as I remember, Loopy's system solving does not attempt divisions, so I'm not surprised this doesn't work. That functionality should really just use isl.