參考資訊：
https://en.wikipedia.org/wiki/RISC-V
| Register | Symbolic | Description |
|---|---|---|
| x0 | zero | always zero |
| x1 | ra | return address |
| x2 | sp | stack pointer |
| x3 | gp | global pointer |
| x4 | tp | thread pointer |
| x5 | t0 | temporary |
| x6-x7 | t1-t2 | temporary |
| x8 | s0/fp | saved register/frame pointer |
| x9 | s1 | saved register |
| x10-x11 | a0-a1 | function argument/return value |
| x12-x17 | a2-a7 | function argument |
| x18-x27 | s2-s11 | saved register |
| x28-x31 | t3-t6 | temporary |
| f0-f7 | ft0-ft7 | temporary |
| f8-f9 | fs0-fs1 | saved register |
| f10-f11 | fa0-fa1 | argument/return value |
| f12-f17 | fa2-fa7 | argument |
| f18-f27 | fs2-fs11 | saved register |
| f28-f31 | ft8-ft11 | temporary |