Abstract: A method, system and computer program product for generating a coverage model to describe a testing scheme for a simulated system are described. In a preferred embodiment, a simulated system is tested with a testing simulation program. A simple event database is generated with the testing simulation program. Results of a checker analysis from the testing with the testing simulation program are obtained, and coverage data is created from a coverage model configuration file, the simple event database and the results of the checker analysis.

Abstract: A method and apparatus for verification of coherence for shared cache components in a system verification environment are provided. With the method and apparatus, stores to the cache are applied to a cache functional simulator in the order that they occur in the trace information from the canonical tracers. However, rather than updating the cache simulator with the actual data stored, the performed time of the store event is applied to the simulator as data. The cache simulator stores the latest performed time for each byte of each cache line in the simulated cache, in an associated data structure. For each load event that is encountered in the trace information for a byte, a comparison is made between a global expected data age of the data in the cache and the performed time associated with the byte. If the data age in the simulated cache for the byte is less than the global expected data age, i.e. a latest previously encountered data age, then a cache coherence violation has occurred.

Abstract: A method, system, and apparatus for placing and removing data elements into a bi-directionally growing first in last out data structure is provided. In one embodiment, in response to a request to place a data element into the data structure, a head pointer is advanced one memory location in a direction indicated by a state of a direction flag. The new data element is placed into the memory location indicated by the head pointer. The position of the head pointer and the base pointer are swapped in preparation for receiving a new data element and the state of the direction flag is reversed to indicate growth of the data structure in the opposite direction. In response to a request to remove a data element from the data structure, the head and base pointers are swapped and the state of the direction flag is reversed.

Abstract: A method and apparatus for verification of coherence for shared cache components in a system verification environment are provided. With the method and apparatus, stores to the cache are applied to a cache functional simulator in the order that they occur in the trace information from the canonical tracers. However, rather than updating the cache simulator with the actual data stored, the performed time of the store event is applied to the simulator as data. The cache simulator stores the latest performed time for each byte of each cache line in the simulated cache, in an associated data structure. For each load event that is encountered in the trace information for a byte, a comparison is made between a global expected data age of the data in the cache and the performed time associated with the byte. If the data age in the simulated cache for the byte is less than the global expected data age, i.e. a latest previously encountered data age, then a cache coherence violation has occurred.

Abstract: A method, computer program product and data processing system for verifying cumulative ordering. In one embodiment of the present invention a method comprises the step of selecting a memory barrier instruction issued by a particular processor. The method further comprises selecting a first cache line out of a plurality of cache lines to be paired with one or more of the remaining of the plurality of cache lines. If a load memory instruction executed after the memory barrier instruction in the first cache line was identified, then the first cache line selected will be paired with a second cache line. If a load memory instruction executed before the memory barrier instruction in the second cache line was identified, then a pair of load memory instructions has been identified. Upon identifying the second load memory instruction, a first and second reload of the first and second cache lines are identified.

Abstract: A system and method for verifying cache coherency in a multi-node, NUMA system includes a transaction modification unit configured to receive event traces generated by a simulation tool. The modification unit modifies transactions that are propagated to another node in the NUMA system and thus result in two bus transactions, a home node transaction (HNT) and a foreign node transaction (FNT). More specifically, the modification unit merges a FNT and its corresponding HNT into a single merge transaction (MT) under a prescribed set of merging rules. The MT has properties of the both the FNT and the HNT. The FNT and HNT are deleted from the event trace and replaced by their corresponding MT to create a modified event trace that is suitable for coherency checking by a single system coherency checker.

Abstract: In a method, system, and apparatus for managing storage of data elements, a storage area having a first and second end is provided for storing the data elements. In the storage area, a first stack of data elements has first and second ends respectively facing the first and second ends of the storage area, and a second stack has data elements located proximate both ends of the first stack. That is, the second stack is split, with the first stack interposed between data elements of the second stack. Likewise, there may be a third and fourth stack, and so on, which are split into more than one part. The stacks increase in size toward both the first end of the storage area and the second end of the storage area, responsive to the storing of successive ones of the data elements in the respective stacks. Furthermore, the increasing in size of one of the split stacks may include increasing away from the first stack, or alternatively, increasing toward the first stack.

Abstract: A method, system, and apparatus for managing data elements in a storage area is disclosed. A storage area, with a first and second end, is provided for storing data elements. The data elements are stored in a first stack, also having a first and second end. Space in the storage area for the first stack includes a first space proximate the first end of the first stack, and a second space proximate the second end of the first stack. The storing of one of the data elements in the first stack includes selecting between storing in the first space or the second space, responsive to the relative sizes of the two spaces. Data elements are also stored in the storage area in a second stack. Space available in the storage area for data elements of the second stack includes the above mentioned first and second spaces, that is, the space proximate the first end of the first stack, and the space proximate the second end of the first stack.

Abstract: A system and method for verifying cache coherency in a multi-node, NUMA system includes a transaction modification unit configured to receive event traces generated by a simulation tool. The modification unit modifies transactions that are propagated to another node in the NUMA system and thus result in two bus transactions, a home node transaction (HNT) and a foreign node transaction (FNT). More specifically, the modification unit merges a FNT and its corresponding HNT into a single merge transaction (MT) under a prescribed set of merging rules. The MT has properties of the both the FNT and the HNT. The FNT and HNT are deleted from the event trace and replaced by their corresponding MT to create a modified event trace that is suitable for coherency checking by a single system coherency checker.

Abstract: A method, computer program product and data processing system for verifying cumulative ordering. In one embodiment of the present invention a method comprises the step of selecting a memory barrier instruction issued by a particular processor. The method further comprises selecting a first cache line out of a plurality of cache lines to be paired with one or more of the remaining of the plurality of cache lines. If a load memory instruction executed after the memory barrier instruction in the first cache line was identified, then the first cache line selected will be paired with a second cache line. If a load memory instruction executed before the memory barrier instruction in the second cache line was identified, then a pair of load memory instructions has been identified. Upon identifying the second load memory instruction, a first and second reload of the first and second cache lines are identified.