riscv / riscv-p-spec

RISC-V Packed SIMD Extension
https://jira.riscv.org/browse/RVG-129
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Opcode policy #108

Open marcfedorow opened 3 years ago

marcfedorow commented 3 years ago

Standard opcodes use 5th bit to indicate rs2 presence and 26th bit (?) to indicate rs3 presence. It should probably follow this because otherwise P-ext makes validity checks too hard.