## Equivalence checking in the presence of incompletely specified boxes (2002)

Venue: | IN ITG/GI/GMM-WORKSHOP “METHODEN UND BESCHREIBUNGSSPRACHEN ZUR MODELLIERUNG UND VERIFIKATION VON SCHALTUNGEN UND SYSTEMEN" |

Citations: | 1 - 1 self |

### BibTeX

@MISC{Scholl02equivalencechecking,

author = {Christoph Scholl and Bernd Becker},

title = {Equivalence checking in the presence of incompletely specified boxes},

year = {2002}

}

### OpenURL

### Abstract

We consider the problem of checking whether an implementation which contains parts with incomplete information is equivalent to a given full specification. We study implementations which are not completely specified, but contain boxes which are associated with incompletely specified functions (called Incompletely Specified Boxes or IS--Boxes). After motivating the use of implementations with Incompletely Specified Boxes we define our notion of equivalence for this kind of implementations and present a method to solve the problem. A series of experimental results demonstrates the effectiveness and feasibility of the methods presented.

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Citation Context ...ly specified IP cores). In this paper we present a method to solve the problem of equivalence checking for implementations with IS--Boxes. The problem is reduced to a symbolic, ROBDD based simulation =-=[4]-=- of the specification and a modified version of the implementation followed by a simple check for equality of ROBDDs. Although we are using ROBDDs in our implementation of the method, it is straightfo... |

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Citation Context ...tal results To evaluate our method for equivalence checking in the presence of IS--Boxes we implemented the described procedure using CUDD 2.3.0 [31] as the underlying BDD package. Dynamic reordering =-=[28]-=- was activated during all experiments. The experiments were performed on a PentiumIII PC with 550 MHz, 1 GB memory, running Linux 6.3. Although, for the purpose of this paper, our implementation is re... |

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Citation Context ...ll possible assignments to the don't cares. 5 Experimental results To evaluate our method for equivalence checking in the presence of IS--Boxes we implemented the described procedure using CUDD 2.3.0 =-=[31]-=- as the underlying BDD package. Dynamic reordering [28] was activated during all experiments. The experiments were performed on a PentiumIII PC with 550 MHz, 1 GB memory, running Linux 6.3. Although, ... |

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Citation Context .... Growing interest in universities and industry has lead to new results and significant advances concerning topics like property checking, state space traversal and combinational equivalence checking =-=[7, 10, 24, 19, 8, 26, 18]-=-. For the purpose of this paper combinational equivalence checking is of particular interest. Here, the task is to check whether the Boolean functions corresponding to the specification and the implem... |

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Citation Context ...One possibility is to translate implementation and specification into one Boolean formula which is satisfiable if and only if implementation and specification do not realize the same Boolean function =-=[32, 22, 13]-=-. As an alternative, implementation and specification can be transformed into a canonical form such that the equivalence check reduces to a check whether the canonical representations of implementatio... |

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Citation Context ...23, 19, 8, 26]. Recently, the problem of `Black Box Equivalence Checking', which occurs when the specification is known, but only parts of the implementation are finished or known, has been addressed =-=[16, 14, 29]-=-. Parts of the implementation which are not finished or known are combined into `Black Boxes'. An error is found in an implementation with Black Boxes, if the implementation differs from the specifica... |

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Citation Context ...nstance, the well--known bug in the Pentium floating point divider [30] was probably due to the incorrect assumption that certain inputs of the PD table to generate the quotient bits were don't cares =-=[5]-=-. Another possible application of IS--Boxes could be the use of incompletely specified Intellectual Property cores (IP cores) in an implementation. Under the assumption that the IP vendor does not pub... |

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Citation Context ...ed: In this case the flexibility has to be expressed by Boolean relations or by sets of Boolean relations, since the degree of freedom given at one output of an IS--Box depends upon the other outputs =-=[33]-=-. Also in this case we would need the complete information on flexibility for the IS--Boxes to decide whether the given don't care sets for the IS--Boxes are not correct. Fortunately, we do not need t... |

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