ios - iOS 错误中的内联汇编

Question

整数 x;
__asm __volatile("movl %0, %%sp":"=r"(x)::"%sp");
我想将 sp 存储到 x。
错误:

error: unexpected token in operand
    __asm __volatile("movl  %0,  %%sp":"=r"(x)::"%sp");
                     ^
:1:13: note: instantiated into assembly here
        movl  r0,  %sp
                   ^
1 warning and 1 error generated.

Answer 1

我找到了我的解决方案:

asm volatile("mov %0, sp \n\t":"=r"(x));