DECL_SC_REG        44 vm_exec.c          DECL_SC_REG(VALUE, a, "12");
DECL_SC_REG        45 vm_exec.c          DECL_SC_REG(VALUE, b, "13");
DECL_SC_REG        53 vm_exec.c          DECL_SC_REG(VALUE *, pc, "di");
DECL_SC_REG        54 vm_exec.c          DECL_SC_REG(rb_control_frame_t *, cfp, "si");
DECL_SC_REG        58 vm_exec.c          DECL_SC_REG(VALUE *, pc, "14");
DECL_SC_REG        59 vm_exec.c          DECL_SC_REG(rb_control_frame_t *, cfp, "15");