llvm's debug build for that source file:

 Performance counter stats for './test':

             1,593      cache-misses                                                
           103,927      instructions              #    0.79  insn per cycle         
           131,249      cycles                                                      

custom codegen for that source file:
 Performance counter stats for './test':

             1,400      cache-misses                                                
            91,315      instructions              #    0.73  insn per cycle         
           125,627      cycles