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/* Tests that Valgrind coredump support works correctly by producing
a core dump analyzable by mdb. */
#include <stdio.h>
#include <sys/types.h>
__attribute__((noinline))
static void inner(void)
{
uint16_t cs, ds, ss, es, fs, gs;
/* Print segment registers as they cannot be set to arbitrary
values. */
__asm__ __volatile__(
"movw %%cs, %0\n"
"movw %%ds, %1\n"
"movw %%ss, %2\n"
"movw %%es, %3\n"
"movw %%fs, %4\n"
"movw %%gs, %5\n"
: "=m" (cs), "=m" (ds), "=m" (ss), "=m" (es), "=m" (fs), "=m" (gs));
printf("cs=%#x ds=%#x ss=%#x es=%#x fs=%#x gs=%#x\n",
cs, ds, ss, es, fs, gs);
/* Set other registers to apriori known values. */
__asm__ __volatile__(
"movl $0x101, %%eax\n"
"movl $0x102, %%ebx\n"
"movl $0x103, %%ecx\n"
"movl $0x104, %%edx\n"
"movl $0x105, %%esi\n"
"movl $0x106, %%edi\n"
// not %ebp as mdb is then not able to reconstruct stack trace
"movl $0x108, %%esp\n"
"movl $0x1234, (%%eax)\n" // should cause SEGV here
"ud2" // should never get here
: // no output registers
: // no input registers
: "memory", "%eax", "%ebx", "%ecx", "%edx", "%esi", "%edi", "%esp");
}
__attribute__((noinline))
static void outer(void)
{
inner();
}
int main(int argc, const char *argv[])
{
outer();
return 0;
}
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