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#
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# pylint: disable=invalid-name, unused-variable, trailing-whitespace
"""Schedule for softmax operator"""
from tvm import te

def schedule_softmax(outs):
    """Schedule for softmax op.

    Parameters
    ----------
    outs: Array of Tensor
          The computation graph description of softmax in the format
          of an array of tensors.

    Returns
    -------
    sch: Schedule
        The computation schedule for the op.
    """
    outs = [outs] if isinstance(outs, te.tensor.Tensor) else outs
    s = te.create_schedule([x.op for x in outs])
    softmax = outs[0]

    op_tag = softmax.op.tag
    if op_tag == 'softmax_output':
        expsum = softmax.op.input_tensors[1]
        exp = softmax.op.input_tensors[0]
        max_elem = s[exp].op.input_tensors[1]
    elif op_tag == 'log_softmax_output':
        exp = None
        max_elem = softmax.op.input_tensors[1]
        expsum = softmax.op.input_tensors[2]
    else:
        raise ValueError('Tag is expected to be softmax_output or log_softmax_output. \
                         Got {0}'.format(op_tag))

    if exp is not None:
        s[exp].opengl()

    s[max_elem].opengl()
    s[expsum].opengl()
    s[softmax].opengl()
    return s
