macro-selection

Choose which modules of a large design to harden as macros by their interfaces in space (pins per micron of perimeter, from the RTL) and in time (registered, shallow boundary crossings, from a hierarchical synthesis), then plan the parent floorplan those interfaces dictate: pin sides, aspect ratios, channels, a logic region, the die. Use when a hierarchical flow's global route will not converge, when a macro's pin side is a wall, or before hardening anything on a design that needs breaking up.