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            Last change
 on this file since 03ac869 was             525b5ef, checked in by Peter A. Buhr <pabuhr@…>, 6 years ago           | 
        
        
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add documentation 
 
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            File size:
            571 bytes
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| 1 | #include <stdio.h>
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| 2 | 
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| 3 | #include "bench.h"
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| 4 | 
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| 5 | // Does a "lock add" on entry and a "lock sub" on exit => 2 atomic instructions making it the most expensive
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| 6 | // atomic test.
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| 7 | 
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| 8 | volatile int value;
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| 9 | 
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| 10 | void __attribute__((noinline)) do_call() {
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| 11 |         __atomic_add_fetch( &value, 1, __ATOMIC_SEQ_CST );
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| 12 |         asm volatile ("");
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| 13 |         __atomic_sub_fetch( &value, 1, __ATOMIC_SEQ_CST );
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| 14 | }
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| 15 | 
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| 16 | int main( int argc, char * argv[] ) {
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| 17 |         BENCH_START()
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| 18 |         BENCH(
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| 19 |                 for (size_t i = 0; i < times; i++) {
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| 20 |                         do_call();
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| 21 |                 },
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| 22 |                 result
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| 23 |         )
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| 24 |         printf( "%g\n", result );
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| 25 | }
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| 26 | 
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| 27 | // Local Variables: //
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| 28 | // tab-width: 4 //
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| 29 | // End: //
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