(4) Consider the following PROMELA program that tries to provide a solution to mutual exclusion: 1...

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(4) Consider the following PROMELA program that tries to provide a solution to mutual exclusion: 1 byte in; 2 byte x, y, z; 3 active [2] proctype user() 4 { byte me = _pid+1; /* me is 1 or 2 */ 5 L1 x me; 6 L2: if 7 :: 8 :: 9 fi; (y!=0 && y != me) -> goto Ll /* try a (y == 0 y == me) 10 L3: z = me; 11 L4: if 12 :: (x = me) -> goto Ll /* try again */ 13 :: (x == me) 14 fi; 15 L5: yme; orial and Lab Practice (Task 4 Assessment 15%) 16 L6: if 590 me) > goto Ll /* try again */ :: (z == me) success */ 17 :: (z 18 19 fi; 20 L7: 21 22 23 24 goto L1 25} in = in+1; assert (in == 1); in in 1; Run this program with SPIN. Try to find a computation that leads to the assertion violation by studying the algorithm. (4) Consider the following PROMELA program that tries to provide a solution to mutual exclusion: 1 byte in; 2 byte x, y, z; 3 active [2] proctype user() 4 { byte me = _pid+1; /* me is 1 or 2 */ 5 L1 x me; 6 L2: if 7 :: 8 :: 9 fi; (y!=0 && y != me) -> goto Ll /* try a (y == 0 y == me) 10 L3: z = me; 11 L4: if 12 :: (x = me) -> goto Ll /* try again */ 13 :: (x == me) 14 fi; 15 L5: yme; orial and Lab Practice (Task 4 Assessment 15%) 16 L6: if 590 me) > goto Ll /* try again */ :: (z == me) success */ 17 :: (z 18 19 fi; 20 L7: 21 22 23 24 goto L1 25} in = in+1; assert (in == 1); in in 1; Run this program with SPIN. Try to find a computation that leads to the assertion violation by studying the algorithm.

Answer rating: 100% (QA)

The provided PROMELA program appears to be an attempt at implementing a mutual exclusion algorithm To find a computation that leads to the assertion violation we can analyze the program and identify t... View the full answer