Or, just "to hell with it" and just take the entire opcode and stuff C into it, no regard for R/I/U/S and instead do whatever we like.
+| 15 14 13 | 12 | 11 10 9 8 7 | 6 5 4 3 2 | 1 0
+ funct4 rd/rs1 rs2 op
+funct3 imm rd/rs1 imm op
+funct3 imm rs2 op
+funct3 imm rd â\80² op
+funct3 imm rs1 â\80² imm rd â\80² op
+funct3 imm rs1 â\80² imm rs2 â\80² op
+ funct6 rd â\80² /rs1 â\80² funct2 rs2 â\80² op
+funct3 offset rs1 â\80² offset op
+funct3 jump target op
+
Questions
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