| #include <stdio.h> |
| #include <stdlib.h> |
| |
| int main(int argc, char **argv) |
| { |
| unsigned long sp1; |
| unsigned long sp2; |
| unsigned long sp3; |
| unsigned short fs1; |
| unsigned short fs2; |
| |
| fs1 = 0x0003; |
| |
| asm("movw %4, %%fs\n" |
| "movl %%esp, %0\n" |
| "pushw %%fs\n" |
| "movl %%esp, %1\n" |
| "popw %%fs\n" |
| "movl %%esp, %2\n" |
| "movw %%fs, %3\n" |
| : "=m" (sp1), "=m" (sp2), "=m" (sp3), "=m" (fs2) |
| : "m" (fs1) |
| : "ax" |
| ); |
| |
| printf("sp change after push = %ld\n", sp2 - sp1); |
| printf("sp change after pop = %ld\n", sp3 - sp2); |
| printf("fs after push and pop = %04x\n", fs1); |
| |
| asm("movw %4, %%fs\n" |
| "movl %%esp, %0\n" |
| "pushl %%fs\n" |
| "movl %%esp, %1\n" |
| "popl %%fs\n" |
| "movl %%esp, %2\n" |
| "movw %%fs, %3\n" |
| : "=m" (sp1), "=m" (sp2), "=m" (sp3), "=m" (fs2) |
| : "m" (fs1) |
| : "ax" |
| ); |
| |
| printf("sp change after push = %ld\n", sp2 - sp1); |
| printf("sp change after pop = %ld\n", sp3 - sp2); |
| printf("fs after push and pop = %04x\n", fs1); |
| |
| exit(0); |
| } |