Contribute Andes's the MC layer support of RVP extension.
The encoding of RVP instructions is according to 0.9.11 version in https://github.com/riscv/riscv-p-spec/.
There are three sub-extensions in RVP.
zbpbo contains instructions overlap with the B extension.
zpn is a basic sub-extension. Most of instructions are belong to zpn.
zpsfoperand is the instruction will read or write 64-bit operands. On RV32, 64-bit operand is even/odd paired-register.
p = zbpbo + zpn + zpsfoperand
This patch has the tests for assemble/disassemble each instructions.
There are four test files for invalid assembly testing.
rvp-invalid.s is for invalid immediate operand in zpn extension for both RV32 and RV64.
rv32zpsfoperand-invalid.s shows that operand should be even register for even/odd paired-register operand on RV32.
rv64zpsfoperand-invalid.s are for invalid immediate operand in zpsfoperand extension on RV64.
rv64zpn-invalid.s are for invalid immediate operand for RV64 only instructions.