# SYSTEM
ecall     11..7=0 19..15=0 31..20=0x000 14..12=0 6..2=0x1C 1..0=3
ebreak    11..7=0 19..15=0 31..20=0x001 14..12=0 6..2=0x1C 1..0=3
uret      11..7=0 19..15=0 31..20=0x002 14..12=0 6..2=0x1C 1..0=3
sret      11..7=0 19..15=0 31..20=0x102 14..12=0 6..2=0x1C 1..0=3
mret      11..7=0 19..15=0 31..20=0x302 14..12=0 6..2=0x1C 1..0=3
dret      11..7=0 19..15=0 31..20=0x7b2 14..12=0 6..2=0x1C 1..0=3
sfence.vma 11..7=0 rs1 rs2 31..25=0x09  14..12=0 6..2=0x1C 1..0=3
wfi       11..7=0 19..15=0 31..20=0x105 14..12=0 6..2=0x1C 1..0=3
csrrw     rd      rs1      imm12        14..12=1 6..2=0x1C 1..0=3
csrrs     rd      rs1      imm12        14..12=2 6..2=0x1C 1..0=3
csrrc     rd      rs1      imm12        14..12=3 6..2=0x1C 1..0=3
csrrwi    rd      rs1      imm12        14..12=5 6..2=0x1C 1..0=3
csrrsi    rd      rs1      imm12        14..12=6 6..2=0x1C 1..0=3
csrrci    rd      rs1      imm12        14..12=7 6..2=0x1C 1..0=3