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System Invariants

forall C, R:
forall pc:
   SystemC,R(pc) =>
      always
         and
            count >= 0
            R =
               count +
               number i in [1,C]: pci = critical pci = release +
               number i in [1,C], j in N1i: clienti[j] = grant
               number i in [1,C], j in N1i: serveri[j] = release +
            exists j in [1,C]: wait[j] =>
               count = 0
 
 
 
 
 
Counter is non-negative.
 
Counter complements number of
processes using resource plus number of
pending release and grant messages.
 
Grants only deferred as long as necessary.

Key knowledge about the designed system.


Author: Wolfgang Schreiner
Last Modification: April 22, 1999

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