RS1_MASK
(MASK_SD | RS2_MASK | RS1_MASK)))
(MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK)))
(MASK_SD | RS2_MASK | RS1_MASK))) {
(MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) {
#define rs1_index ((instr & RS1_MASK) >> RS1_SHIFT)
rs1 = (insn & RS1_MASK) >> RS1_SHIFT;
MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK, m_op },