ARM base instruction -- b.cs

xiaozhiwise2024-09-06 14:06

Branch causes an unconditional branch to a label at a PC-relative offset, with a hint that this is not a subroutine call or return.

在PC相对偏移处对标签进行无条件分支，并提示这不是子程序调用或返回。

操作码助记符标志含义

0x2 0010 CS/HS C = 1 无符号数大于或等于

402c88: f9401fe2 ldr x2, $sp, #56$ // x2="%s/%d/task/%d/stat"

402c8c: 2a1c03e5 mov w5, w28 // w5=w28=tid

402c90: f94047e1 ldr x1, $sp, #136$ // x1=len

402c94: 2a1303e4 mov w4, w19 // w4=w19=pid

402c98: aa1a03e3 mov x3, x26 // x3=x26="/proc"

402c9c: 97fffb91 bl 401ae0 <snprintf@plt>

int nbytes = snprintf(path, len, "%s/%d/task/%d/stat", "/proc", pid, tid);

402ca0: b94013e1 ldr w1, $sp, #16$ // w1 = len

402ca4: 6b01001f cmp w0, w1 // w0 = nbytes

402ca8: 54000a02 b.cs 402de8 <ferror@plt+0xf08> // b.hs, b.nlast

if (nbytes < 0 || nbytes >= len)

perror("get_threadname: snprintf");