Typically fabless CPU/MCU companies design and implement netlists to these CPU designs. It includes all of the logic to implement the CPU. This netlist/VHDL/Ver

Typically fabless CPU/MCU companies design and implement netlists to these CPU designs. It includes all of the logic to implement the CPU. This netlist/VHDL/Verilog design is the protected IP they sell, as well as the rights to re-use, etc. The IP itself can be placed into semiconductor fabric and combined with many other parts such as peripherals, flash memory, sram, etc.