VexRiscv - A FPGA friendly 32 bit RISC-V CPU implementation

  •        29

For commercial support, please contact The following numbers were obtained by synthesizing the CPU as toplevel without any specific synthesis options to save area or to get better maximal frequency (neutral). The clock constraint is set to an unattainable value, which tends to increase the design area. The dhrystone benchmark was compiled with the -O3 -fno-inline option. All the cached configurations have some cache trashing during the dhrystone benchmark except the VexRiscv full max perf one. This of course reduces the performance. It is possible to produce dhrystone binaries which fit inside a 4KB I$ and 4KB D$ (I already had this case once) but currently it isn't the case. The CPU configurations used below can be found in the src/scala/vexriscv/demo directory.



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