Abstract: Capabilities are added to a Hardware Verification Language that facilitates the generation of test data. Random number sources, called random variables, can be produced by adding a randomness attribute to a variable declaration of a class definition. A “randomize” method call to a class instance produces a random value for each random variable. Constraint blocks, of a class definition, control random variables with constraint expressions. Dependency, of random variable value assignment, as determined by constraint expressions, can be expressed by a DAG. A constraint expression is converted into ranges of permissible values, from which a value is randomly chosen by a randomize method. A “boundary” method call sequentially selects a combination of boundary values, for each random variable, from each random variable's set of ranges. Coordinated selection of a boundary values permits all combinations of boundary values to be produced through successive boundary calls.

Abstract: The present invention adds capabilities to a Hardware Verification Language (HVL) which facilitate the generation of random test data. Sources of random numbers are easily produced by simply adding a randomness attribute to a variable declaration of a class definition. Such variables are called random variables. A “randomize” method call may be made to an instance of the class definition to produce random values for each random variable. The values assigned to random variables are controlled using constraint blocks, which are part of the class definition. A constraint block is comprised of constraint expressions. The constraint expressions may impose a linear ordering in which random variable values must be assigned and this dependency is expressed by directed acyclic graphs (DAGs). The constraint expressions constraining each random variable are converted into ranges of permissible values from which a value is chosen at random.

Abstract: The present invention adds capabilities to a Hardware Verification Language (HVL) which facilitate the generation of random test data. Sources of random numbers are easily produced by simply adding a randomness attribute to a variable declaration of a class definition. Such variables are called random variables. A “randomize” method call may be made to an instance of the class definition to produce random values for each random variable. The values assigned to random variables are controlled using constraint blocks, which are part of the class definition. A constraint block is comprised of constraint expressions, where each constraint expression limits the values that can be assigned to a random variable on the left-hand-side (lhs) of the constraint expression. If a constraint block of an instance is active or ON, then all the constraint expressions in the block will act to constrain their lhs random variable.

Abstract: The present invention adds capabilities to a Hardware Verification Language (HVL) which facilitate the generation of random test data. Sources of random numbers are easily produced by simply adding a randomness attribute to a variable declaration of a class definition. Such variables are called random variables. A “randomize” method call may be made to an instance of the class definition to produce random values for each random variable. The values assigned to random variables are controlled using constraint blocks, which are part of the class definition. A constraint block is comprised of constraint expressions, where each constraint expression limits the values that can be assigned to a random variable on the left-hand-side (lhs) of the constraint expression. A constraint_expression can constrain any random variable which has been declared at its level in the class hierarchy, or at any higher level.

Abstract: The present invention adds capabilities to a Hardware Verification Language (HVL) which facilitate the generation of random test data. Sources of random numbers are easily produced by simply adding a randomness attribute to a variable declaration of a class definition. Such variables are called random variables. A “randomize” method call may be made to an instance of the class definition to produce random values for each random variable. The values assigned to random variables are controlled using constraint blocks, which are part of the class definition. A constraint block is comprised of constraint expressions, where each constraint expression limits the values that can be assigned to a random variable on the left-hand-side (lhs) of the constraint expression. Because random variables may also appear on the right-hand-side (rhs) of a constraint expression there is an ordering in which random variable values must be assigned and this dependency is expressed by directed acyclic graphs (DAGs).