An apparatus for designing a semiconductor integrated circuit having a
configurable processor includes: a software information storage section
storing software information including software descriptions; a hardware
information storage section storing hardware information including
hardware descriptions of the semiconductor integrated circuit; a
processor information storage section storing processor information; a
hardware implementation specification section specifying an algorithm of
a portion to be implemented by hardware from among the software
descriptions; a hardware changing section generating hardware
descriptions from the algorithm of the specified portion, and changing
the hardware information and the processor information; a software
changing section generating software descriptions in which the algorithm
of the specified portion is replaced with an algorithm for controlling
the implemented hardware, and changing the software information; and a
performance analyzer analyzing a performance of the semiconductor
integrated circuit based on the changed software information, the changed
hardware information and the changed processor information.