2026-01-21 18:59:54 +08:00
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C MP+poonceonces
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(*
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* Result: Sometimes
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*
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* Can the counter-intuitive message-passing outcome be prevented with
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* no ordering at all?
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*)
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{}
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2026-01-29 22:25:33 +08:00
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P0(int *buf, int *flag) // Producer
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2026-01-21 18:59:54 +08:00
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{
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2026-01-29 22:25:33 +08:00
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WRITE_ONCE(*buf, 1);
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WRITE_ONCE(*flag, 1);
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2026-01-21 18:59:54 +08:00
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}
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2026-01-29 22:25:33 +08:00
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P1(int *buf, int *flag) // Consumer
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2026-01-21 18:59:54 +08:00
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{
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int r0;
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int r1;
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2026-01-29 22:25:33 +08:00
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r0 = READ_ONCE(*flag);
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r1 = READ_ONCE(*buf);
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2026-01-21 18:59:54 +08:00
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}
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2026-01-29 22:25:33 +08:00
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exists (1:r0=1 /\ 1:r1=0) (* Bad outcome. *)
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