Abstract: A method for efficiently computing a hash value for a string is disclosed. In one embodiment, such a method includes receiving an original string comprising multiple characters. The method computes an original hash value for the original string. The method produces an updated string by performing at least one of the following updates on the original string: adding leading/trailing characters to the original string; removing leading/trailing characters from the original string, and modifying characters of the original string while preserving the length of the original string. The method then computes an updated hash value for the updated string by performing at least one operation on the original hash value, wherein the at least one operation takes into account the updates that were made to the original string. A corresponding apparatus and computer program product are also disclosed.

Abstract: A computer-implemented process for write barrier elision during program execution receives a request to overwrite a reference, determines whether garbage collection is active and responsive to a determination that garbage collection is active, determines whether a reference object has been scanned. Responsive to a determination that the reference object has not been scanned set a mark bit for the reference object in a modified mark map, the reference object is scanned and a scan bit is set for the reference object in the modified mark map.

Abstract: A method for efficiently computing a hash value for a string is disclosed. In one embodiment, such a method includes receiving an original string comprising multiple characters. The method computes an original hash value for the original string. The method produces an updated string by performing at least one of the following updates on the original string: adding leading/trailing characters to the original string; removing leading/trailing characters from the original string, and modifying characters of the original string while preserving the length of the original string. The method then computes an updated hash value for the updated string by performing at least one operation on the original hash value, wherein the at least one operation takes into account the updates that were made to the original string. A corresponding apparatus and computer program product are also disclosed.