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static int simple_jump(void)
{
asm goto ("jmp %l[label]" : : : : label);
return 0;
label:
return 1;
}
static int three_way_jump(int val, int *addr)
{
*addr = 42;
asm goto ("cmp $0, %1\n\t"
"jg %l[larger]\n\t"
"jl %l[smaller]\n\t"
"incl %0\n\t"
: "=m" (*addr)
: "r" (val)
:
: smaller, larger);
return 1;
smaller:
return 2;
larger:
return 3;
}
static int another_jump(void)
{
asm goto ("jmp %l[label]" : : : : label);
return 70;
/* Use the same label name as in simple_jump to check that
that doesn't confuse our C/ASM symbol tables */
label:
return 71;
}
extern int printf (const char *, ...);
int main(void)
{
int i;
if (simple_jump () == 1)
printf ("simple_jump: okay\n");
else
printf ("simple_jump: wrong\n");
if (another_jump () == 71)
printf ("another_jump: okay\n");
else
printf ("another_jump: wrong\n");
if (three_way_jump(0, &i) == 1 && i == 43)
printf ("three_way_jump(0): okay\n");
else
printf ("three_way_jump(0): wrong (i=%d)\n", i);
if (three_way_jump(1, &i) == 3 && i == 42)
printf ("three_way_jump(1): okay\n");
else
printf ("three_way_jump(1): wrong (i=%d)\n", i);
if (three_way_jump(-1, &i) == 2 && i == 42)
printf ("three_way_jump(-1): okay\n");
else
printf ("three_way_jump(-1): wrong (i=%d)\n", i);
return 0;
}
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