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#include <cinttypes>
#include <cstdint>
#include <cstdio>
int main() {
constexpr uint32_t fill = 0x0F0F0F0F;
uint32_t eax, ebx, ecx, edx, esi, edi;
// need to use 64-bit types due to bug in clang
// https://bugs.llvm.org/show_bug.cgi?id=41748
uint64_t esp, ebp;
asm volatile(
// save esp & ebp
"movd %%esp, %%mm0\n\t"
"movd %%ebp, %%mm1\n\t"
"\n\t"
"movl %8, %%eax\n\t"
"movl %8, %%ebx\n\t"
"movl %8, %%ecx\n\t"
"movl %8, %%edx\n\t"
"movl %8, %%esp\n\t"
"movl %8, %%ebp\n\t"
"movl %8, %%esi\n\t"
"movl %8, %%edi\n\t"
"\n\t"
"int3\n\t"
"\n\t"
// copy new values of esp & ebp
"movd %%esp, %4\n\t"
"movd %%ebp, %5\n\t"
// restore saved esp & ebp
"movd %%mm0, %%esp\n\t"
"movd %%mm1, %%ebp\n\t"
: "=a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx), "=y"(esp), "=y"(ebp),
"=S"(esi), "=D"(edi)
: "i"(fill)
: "%mm0", "%mm1"
);
printf("eax = 0x%08" PRIx32 "\n", eax);
printf("ebx = 0x%08" PRIx32 "\n", ebx);
printf("ecx = 0x%08" PRIx32 "\n", ecx);
printf("edx = 0x%08" PRIx32 "\n", edx);
printf("esp = 0x%08" PRIx32 "\n", static_cast<uint32_t>(esp));
printf("ebp = 0x%08" PRIx32 "\n", static_cast<uint32_t>(ebp));
printf("esi = 0x%08" PRIx32 "\n", esi);
printf("edi = 0x%08" PRIx32 "\n", edi);
return 0;
}
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