ADT
        arm-eh
        ast-experimental
        enum
        forall-pointer-decay
        jacob/cs343-translation
        new-ast-unique-expr
        pthread-emulation
        qualifiedEnum
      
      
        
          | Last change
 on this file since c2bc6d5 was             525b5ef, checked in by Peter A. Buhr <pabuhr@…>, 6 years ago | 
        
          | 
add documentation
 | 
        
          | 
              
Property                 mode
 set to                 100644 | 
        
          | File size:
            835 bytes | 
      
      
| Line |  | 
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| 1 | #include <stdbool.h> | 
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| 2 | #include <stdio.h> | 
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| 3 |  | 
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| 4 | #include "bench.h" | 
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| 5 |  | 
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| 6 | // Does not do a fetch & add. It mimics the cfa protocol to disable interrupts locally, by writing true or false to a | 
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| 7 | // thread_local Boolean. This means the entire protocol is just to "mov" instructions making it extremely cheap. | 
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| 8 |  | 
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| 9 | #define thread_local _Thread_local | 
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| 10 |  | 
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| 11 | thread_local volatile bool value; | 
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| 12 |  | 
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| 13 | void __attribute__((noinline)) do_call() { | 
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| 14 | __atomic_store_n( &value, true, __ATOMIC_RELAXED ); | 
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| 15 | __atomic_signal_fence(__ATOMIC_ACQUIRE); | 
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| 16 | asm volatile (""); | 
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| 17 | __atomic_store_n( &value, false, __ATOMIC_RELAXED ); | 
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| 18 | __atomic_signal_fence(__ATOMIC_RELEASE); | 
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| 19 | } | 
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| 20 |  | 
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| 21 | int main( int argc, char * argv[] ) { | 
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| 22 | BENCH_START() | 
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| 23 | BENCH( | 
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| 24 | for (size_t i = 0; i < times; i++) { | 
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| 25 | do_call(); | 
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| 26 | }, | 
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| 27 | result | 
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| 28 | ) | 
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| 29 | printf( "%g\n", result ); | 
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| 30 | } | 
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| 31 |  | 
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| 32 | // Local Variables: // | 
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| 33 | // tab-width: 4 // | 
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| 34 | // End: // | 
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