SystemC is a standard language being adopted by companies involved in
the design of electronic systems, integrated circuits,
ASIC(Application Specific Integrated Circuits) and ASSP (Application
Specific Standard Product).  Verilog and VHDL are currently the most
popular hardware design languages (ie, HDLs).  Some users of these
languages are migrating to SystemC.  Also, there are some past users
of C++ that use SystemC specifically for hardware modeling or hardware
design verfication.

Who are the top 20 companies that have adopted SystemC or C++, based on
number of active projects or number of users?