35 lines
498 B
Plaintext
35 lines
498 B
Plaintext
C cmpxchg-fail-unordered-1
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(*
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* Result: Sometimes
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*
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* Demonstrate that a failing cmpxchg() operation does not act as a
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* full barrier. (In contrast, a successful cmpxchg() does act as a
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* full barrier.)
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*)
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{}
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P0(int *x, int *y, int *z)
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{
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int r0;
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int r1;
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WRITE_ONCE(*x, 1);
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r1 = cmpxchg(z, 1, 0);
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r0 = READ_ONCE(*y);
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}
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P1(int *x, int *y, int *z)
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{
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int r0;
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int r1;
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WRITE_ONCE(*y, 1);
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r1 = cmpxchg(z, 1, 0);
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r0 = READ_ONCE(*x);
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}
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locations[0:r1;1:r1]
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exists (0:r0=0 /\ 1:r0=0)
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