bolt/test/X86/Inputs/double_jump.cpp

   1 // A contrived example to test the double jump removal peephole.
   2
   3 extern "C" unsigned long bar(unsigned long count) {
   4   return count + 1;
   5 }
   6
   7 unsigned long foo(unsigned long count) {
   8   asm(
   9       "     cmpq  $1,%0\n"
  10       "     je    .L7\n"
  11       "     incq  %0\n"
  12       "     jmp   .L1\n"
  13       ".L1: jmp   .L2\n"
  14       ".L2: incq  %0\n"
  15       "     cmpq  $2,%0\n"
  16       "     jne   .L3\n"
  17       "     jmp   .L4\n"
  18       ".L3: jmp   .L5\n"
  19       ".L5: incq  %0\n"
  20       ".L4: movq  %0,%%rdi\n"
  21       "     pop   %%rbp\n"
  22       "     jmp   .L6\n"
  23       ".L7: pop   %%rbp\n"
  24       "     incq  %0\n"
  25       "     jmp   .L6\n"
  26       ".L6: jmp   bar\n"
  27       :
  28       : "m"(count)
  29       );
  30   return count;
  31 }
  32
  33 int main(int argc, const char* argv[]) {
  34   return foo(38);
  35 }