| Last change
 on this file since 0860d9c was             1bcbf02, checked in by Thierry Delisle <tdelisle@…>, 3 years ago | 
        
          | 
Changed declarations using _Thread_local to use thread.I'm fairly sure they do exactly the same, but thread is:
 
 more consistent with uC++.
Shorter.
Better documented.
 | 
        
          | 
              
Property                 mode
 set to                 100644 | 
        
          | File size:
            795 bytes | 
      
      
| Line |  | 
|---|
| 1 | #include <stdbool.h> | 
|---|
| 2 | #include <stdio.h> | 
|---|
| 3 |  | 
|---|
| 4 | #include "bench.h" | 
|---|
| 5 |  | 
|---|
| 6 | // Does not do a fetch & add. It mimics the cfa protocol to disable interrupts locally, by writing true or false to a | 
|---|
| 7 | // thread_local Boolean. This means the entire protocol is just to "mov" instructions making it extremely cheap. | 
|---|
| 8 |  | 
|---|
| 9 | __thread volatile bool value; | 
|---|
| 10 |  | 
|---|
| 11 | void __attribute__((noinline)) do_call() { | 
|---|
| 12 | __atomic_store_n( &value, true, __ATOMIC_RELAXED ); | 
|---|
| 13 | __atomic_signal_fence(__ATOMIC_ACQUIRE); | 
|---|
| 14 | asm volatile (""); | 
|---|
| 15 | __atomic_store_n( &value, false, __ATOMIC_RELAXED ); | 
|---|
| 16 | __atomic_signal_fence(__ATOMIC_RELEASE); | 
|---|
| 17 | } | 
|---|
| 18 |  | 
|---|
| 19 | int main( int argc, char * argv[] ) { | 
|---|
| 20 | BENCH_START() | 
|---|
| 21 | BENCH( | 
|---|
| 22 | for (size_t i = 0; i < times; i++) { | 
|---|
| 23 | do_call(); | 
|---|
| 24 | }, | 
|---|
| 25 | result | 
|---|
| 26 | ) | 
|---|
| 27 | printf( "%g\n", result ); | 
|---|
| 28 | } | 
|---|
| 29 |  | 
|---|
| 30 | // Local Variables: // | 
|---|
| 31 | // tab-width: 4 // | 
|---|
| 32 | // End: // | 
|---|
       
      
  Note:
 See   
TracBrowser
 for help on using the repository browser.