Macro design techniques are disclosed for facilitating subsequent stage
wiring across the macro. Whitespace areas within the macro are rearranged
to accommodate the wiring. The rearrangement may take the form of
physical rearrangement of the whitespace areas into routing tracks
extending from one side of the macro to another; shielding using, for
example, macro power bussing and/or macro wiring; routing power busses to
the rearranged whitespace; and/or inserting active circuits with pins
accessible to the wiring. In a preferred embodiment, active circuits are
placed into rearranged macro whitespace during the design of subsequent
stages. The rearrangement of the whitespace facilitates the wiring across
the macro so that slew rate and path delay requirements of the subsequent
stage wiring can be maintained, without excessive buffering or rerouting
of wiring.