lldb/test/Shell/Register/Inputs/x86-multithread-read.cpp

   1 #include <cstdint>
   2 #include <mutex>
   3 #include <thread>
   4
   5 std::mutex t1_mutex, t2_mutex;
   6
   7 struct test_data {
   8   uint32_t eax;
   9   uint32_t ebx;
  10
  11   struct alignas(16) {
  12     uint64_t mantissa;
  13     uint16_t sign_exp;
  14   } st0;
  15 };
  16
  17 void t_func(std::mutex &t_mutex, const test_data &t_data) {
  18   std::lock_guard<std::mutex> t_lock(t_mutex);
  19
  20   asm volatile(
  21     "finit\t\n"
  22     "fldt %2\t\n"
  23     "int3\n\t"
  24     :
  25     : "a"(t_data.eax), "b"(t_data.ebx), "m"(t_data.st0)
  26     : "st"
  27   );
  28 }
  29
  30 int main() {
  31   test_data t1_data = {
  32     .eax = 0x05060708,
  33     .ebx = 0x15161718,
  34     .st0 = {0x8070605040302010, 0x4000},
  35   };
  36   test_data t2_data = {
  37     .eax = 0x25262728,
  38     .ebx = 0x35363738,
  39     .st0 = {0x8171615141312111, 0xc000},
  40   };
  41
  42   // block both threads from proceeding
  43   std::unique_lock<std::mutex> m1_lock(t1_mutex);
  44   std::unique_lock<std::mutex> m2_lock(t2_mutex);
  45
  46   // start both threads
  47   std::thread t1(t_func, std::ref(t1_mutex), std::ref(t1_data));
  48   std::thread t2(t_func, std::ref(t2_mutex), std::ref(t2_data));
  49
  50   // release lock on thread 1 to make it interrupt the program
  51   m1_lock.unlock();
  52   // wait for thread 1 to finish
  53   t1.join();
  54
  55   // release lock on thread 2
  56   m2_lock.unlock();
  57   // wait for thread 2 to finish
  58   t2.join();
  59
  60   return 0;
  61 }