Example #1
0
def fixed_to_real(value, point):
    if point < 0:
        return vtypes.SystemTask('itor', fixed_to_int(value, point))

    if point == 0:
        return vtypes.SystemTask('itor', value)

    if isinstance(value, float):
        raise TypeError("value is already float.")

    if isinstance(value, (int, bool)) and isinstance(point, int):
        mag = 2 ** point
        return float(value) / mag

    signed = vtypes.get_signed(value)

    width = value.bit_length()
    msb = (value[width - 1] if isinstance(value, vtypes._Variable) else
           (value >> (width - 1)) & 0x1)

    v0 = (vtypes.SystemTask('itor', fixed_to_int(value, point)) +
          vtypes.SystemTask('itor', fixed_to_int_low(value, point)) /
          vtypes.SystemTask('itor', vtypes.Int(2) ** point))

    nv = vtypes.Unot(value) + 1
    v1 = ((vtypes.SystemTask('itor', fixed_to_int(nv, point)) +
           vtypes.SystemTask('itor', fixed_to_int_low(nv, point)) /
           vtypes.SystemTask('itor', vtypes.Int(2) ** point))) * vtypes.SystemTask('itor', -1)

    return vtypes.Mux(signed and msb == 0, v0, v1)
Example #2
0
    def __init__(self, left, right):
        lpoint = left.point if isinstance(left, _FixedBase) else 0
        rpoint = right.point if isinstance(right, _FixedBase) else 0
        lsigned = vtypes.get_signed(left)
        rsigned = vtypes.get_signed(right)
        point = _max_mux(lpoint, rpoint)
        signed = lsigned and rsigned if not self.overwrite_signed else False
        lwidth = vtypes.get_width(left)
        rwidth = vtypes.get_width(right)

        if lpoint <= rpoint:
            ldata, rdata = adjust(left, right, lpoint, rpoint, signed)
            shift_size = point
        else:
            ldata = left
            rdata = right
            shift_size = point - (lpoint - rpoint)

        try:
            lmsb = ldata[lwidth - 1]
        except:
            lmsb = (ldata >> (lwidth - 1) & vtypes.Int(1, 1, base=2))

        try:
            rmsb = rdata[rwidth - 1]
        except:
            rmsb = (rdata >> (rwidth - 1) & vtypes.Int(1, 1, base=2))

        abs_ldata = (ldata if not lsigned else vtypes.Mux(
            vtypes.Ulnot(lmsb), ldata,
            vtypes.Unot(ldata) + 1))
        abs_rdata = (rdata if not rsigned else vtypes.Mux(
            vtypes.Ulnot(rmsb), rdata,
            vtypes.Unot(rdata) + 1))
        abs_data = vtypes.Divide(abs_ldata, abs_rdata)
        data = (abs_data if not signed else vtypes.Mux(
            vtypes.Eq(lmsb, rmsb), abs_data,
            vtypes.Unot(abs_data) + 1))

        if shift_size > 0:
            data = vtypes.Sll(data, shift_size)

        _FixedSkipUnaryOperator.__init__(self, data, point, signed)
Example #3
0
    def _binary_op_div(self, op, r):
        lvalue = self.value
        lpoint = self.point
        lsigned = self.signed

        if not isinstance(r, Fixed):
            rvalue = r
            rsigned = vtypes.get_signed(r)
            rpoint = 0
        else:
            rvalue = r.value
            rsigned = r.signed
            rpoint = r.point

        point = _max_mux(lpoint, rpoint)
        signed = lsigned and rsigned
        lwidth = lvalue.bit_length()
        rwidth = rvalue.bit_length()
        ldata, rdata = adjust(lvalue, rvalue, lpoint, rpoint, signed)

        try:
            lmsb = ldata[lwidth - 1]
        except:
            lmsb = (ldata >> (lwidth - 1) & 0x1)

        try:
            rmsb = rdata[lwidth - 1]
        except:
            rmsb = (rdata >> (rwidth - 1) & 0x1)

        abs_ldata = (ldata if not lsigned else
                     vtypes.Mux(lmsb == 0, ldata, vtypes.Unot(ldata) + 1))
        abs_rdata = (rdata if not rsigned else
                     vtypes.Mux(rmsb == 0, rdata, vtypes.Unot(rdata) + 1))
        abs_data = op(abs_ldata, abs_rdata)
        data = (abs_data if not signed else
                vtypes.Mux(vtypes.Ors(vtypes.Ands(lmsb, rmsb),
                                      vtypes.Ands(vtypes.Not(lmsb), vtypes.Not(rmsb))),
                           abs_data, vtypes.Unot(abs_data) + 1))

        return Fixed(data, point, signed)
Example #4
0
 def visit_Unot(self, node):
     return vtypes.Unot(self.visit(node.right))