| C IRIW+poonceonces+OnceOnce |
| |
| (* |
| * Result: Sometimes |
| * |
| * Test of independent reads from independent writes with nothing |
| * between each pairs of reads. In other words, is anything at all |
| * needed to cause two different reading processes to agree on the order |
| * of a pair of writes, where each write is to a different variable by a |
| * different process? |
| *) |
| |
| { |
| int x; |
| int y; |
| } |
| |
| P0(int *x) |
| { |
| WRITE_ONCE(*x, 1); |
| } |
| |
| P1(int *x, int *y) |
| { |
| int r0; |
| int r1; |
| |
| r0 = READ_ONCE(*x); |
| r1 = READ_ONCE(*y); |
| } |
| |
| P2(int *y) |
| { |
| WRITE_ONCE(*y, 1); |
| } |
| |
| P3(int *x, int *y) |
| { |
| int r0; |
| int r1; |
| |
| r0 = READ_ONCE(*y); |
| r1 = READ_ONCE(*x); |
| } |
| |
| exists (1:r0=1 /\ 1:r1=0 /\ 3:r0=1 /\ 3:r1=0) |
