arm平台x86平台内嵌汇编

//x86平台 x86指令集，intel风格test.c
#include
int add(void) {
    long eax=4;
    long ebx=2;

   __asm__ __volatile__ ("addl %1, %0"
            : "=b"((long)ebx)
            : "a"((long)eax), "b"((long)ebx)
            : "1"
            );
 
   printf("ebx=%d\n", ebx);
   return 0;
  
}

int main(){
    int a=12;
    char *hello="hello,world\n";
    __asm__(
            ".intel_syntax noprefix\n"
            "mov eax,4\n"
            "mov ebx,1\n"
            "mov ecx,%0\n"
            "mov edx,%1\n"
            "int 0x80\n"
            ".att_syntax\n"
            :
            :"r"(hello),"r"(a)
            :"eax","ebx","ecx","edx"
    );
    add();
    exit(0);

}
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//x86平台 x86指令集 ，at&t风格test.c

#include
int sum(int a, int b)                                
{                                             
 int r;
        __asm__(
 "sub $0x4, %%esp\n"
 "movl 0xc(%%ebp), %%eax\n"
 "addl 0x8(%%ebp),%%eax\n"
 " movl %%eax, 0xfffffffc(%%ebp)\n"
 " movl 0xfffffffc(%%ebp), %%eax\n"
 " movl %%eax, %%eax\n"
  : "=a"(r)
  );                         
      return r;                             
}

int main()
{
        int x = sum(10,2);
        printf("x = %d\n", x);
        return 0;
}

gcc -o test test.c
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//arm 平台，用arm平台的指令集 ，test.c

int main()
{
 //printf("starting...\n");
 //直接内嵌汇编
     __asm__(
            "ldr r0,  =0x30000000\n"//别忘记加个等号
            "mov r1,#1\n"
            "str    r1,[r0]\n"
            );

}

arm-linux-gcc -o test test.c