[DOC BUG] : C.ZEXT.W is a RV64ZCB

Created by: AyoubJalali

Is there an existing CVA6 bug for this?

• I have searched the existing bug issues

Bug Description

Hello @Abdulwadoodd, I saw that you add c.zext.w to the RV32zcb, and I sorry because I didn't notice it, the RISCV specification only describe only RV32 instructions, so I don't think c.zext.w had it place here