DSCR_2
ret = validate_tar_registers(reg, TAR_2, PPR_2, DSCR_2);
FAIL_IF(write_tar_registers(child, TAR_2, PPR_2, DSCR_2));
ptrace_write_running, TAR_2, PPR_2, DSCR_2);
[dscr_1]"i"(DSCR_1), [tar_2]"i"(TAR_2), [dscr_2]"i"(DSCR_2),
[dscr_2]"i"(DSCR_2), [cptr1] "b" (&cptr[1])
FAIL_IF(validate_tar_registers(regs, TAR_2, PPR_2, DSCR_2));