Patent application number | Description | Published |
20080250396 | Transforming Locks in Software Loops - An improved system and computer programming product for acquisition and release of locks within a software program is disclosed. In an exemplary embodiment, a lock within a loop is transformed by relocating acquisition and release instructions from within the loop to positions outside the loop. This may significantly decrease unnecessarily lock acquisition and release during execution of the software program. In order to avoid contention problems which may arise from acquiring and keeping a lock on an object over a relatively long period of time, a contention test may be inserted into the loop. Such a contention test may temporarily release the lock if another thread in the software program requires access to the locked object. | 10-09-2008 |
20090125893 | METHOD AND APPARATUS FOR MANAGING VARIABLE ASSIGNMENTS IN A PROGRAM - The illustrative embodiments described herein provide a computer-implemented method, apparatus, and computer program product for managing variable assignments in a program. The process identifies a set of variable assignments that is live on a portion of paths to form a set of identified variable assignments. Each of the set of identified variable assignments assign a value to at least one variable of a set of variables. The process determines a set of program points at which the set of identified variable assignments is live on all paths. The process also moves the set of identified variable assignments to the set of program points in response to determining that the set of identified variable assignments is movable to the set of program points. | 05-14-2009 |
20090132780 | CACHE LINE RESERVATIONS - Illustrative embodiments provide a computer implemented method, an apparatus in the form of a data processing system and a computer program product for cache line reservations. In one embodiment, the computer implemented method comprises, dividing a memory into an unreserved section and a set of reserved sections. The method performs selected allocations of the memory only from the set of reserved sections, and performing un-selected allocations of the memory from the unreserved section. The method further mapping a specified selected allocation of the memory to a same corresponding line of cache memory each time the mapping for the specified selected allocation of the memory occurs, thereby maintaining locality. | 05-21-2009 |
20090235240 | METHOD FOR JIT COMPILER TO OPTIMIZE REPETITIVE SYNCHRONIZATION - Repetitive synchronization in program code is optimized through lock coarsening that is performed subject to a number of constraints. Using a forward pass over the program code followed by a backward pass, region extent bits may be determined that identify the points in the program where object locking can be coarsened. The program code may then be modified to realize coarsened locking regions determined based on the region extent bits. Alternatively, previously determined value numbers may provide much of the information collected by the two passes. In such a case, a single pass over the program code may locate features that limit lock coarsening opportunities. A set of synchronization operations that can be removed may then be determined and used when modifying the program code to coarsen locking regions. | 09-17-2009 |
20120042325 | Deep Copying Objects in a Collocated Environment - Systems and methods of passing arguments between client and server contexts may provide for detecting an in-process call between a client and a server, wherein the client and the server share a common virtual machine instance. An object copy from a source object of the in-process call to a destination object can be conducted based on an internal class structure of the virtual machine instance. The object copy procedure may be repeated for a plurality of source objects of the in-process call. | 02-16-2012 |
20120117549 | Method and Data Processing System for Partial Inlining with Software Based Restart - A compiler and method of optimizing code by partial inlining of a subset of blocks of called blocks of code into calling blocks of code. A restart of the called blocks of code is provided for the case where non-inlined blocks of code are reached at run time. Blocks selected for partial inlining may include global side effects depending on the computer program environment. Global side effects in the selected blocks of code leading to a restart are sanitized in order to defer changes to the global state of the computer program. | 05-10-2012 |
20120192206 | Deep Copying Objects in a Collocated Environment - Systems and methods of passing arguments between client and server contexts may provide for detecting an in-process call between a client and a server, wherein the client and the server share a common virtual machine instance. An object copy from a source object of the in-process call to a destination object can be conducted based on an internal class structure of the virtual machine instance. The object copy procedure may be repeated for a plurality of source objects of the in-process call. | 07-26-2012 |
20130080706 | PREVENTION OF CLASSLOADER MEMORY LEAKS IN MULTITIER ENTERPRISE APPLICATIONS - A classloader cache class definition is obtained by a processor. The classloader cache class definition includes code that creates a classloader object cache that is referenced by a strong internal reference by a classloader object in response to instantiation of the classloader cache class definition. A classloader object cache is instantiated using the obtained classloader cache class definition. The strong internal reference is created at instantiation of the classloader object cache. A public interface to the classloader object cache is provided. The public interface to the classloader object cache operates as a weak reference to the classloader object cache and provides external access to the classloader object cache. | 03-28-2013 |
20130080707 | PREVENTION OF CLASSLOADER MEMORY LEAKS IN MULTITIER ENTERPRISE APPLICATIONS - A classloader cache class definition is obtained by a processor. The classloader cache class definition includes code that creates a classloader object cache that is referenced by a strong internal reference by a classloader object in response to instantiation of the classloader cache class definition. A classloader object cache is instantiated using the obtained classloader cache class definition. The strong internal reference is created at instantiation of the classloader object cache. A public interface to the classloader object cache is provided. The public interface to the classloader object cache operates as a weak reference to the classloader object cache and provides external access to the classloader object cache. | 03-28-2013 |
20130243175 | EFFICIENT INTERPRETER PROFILING TO OBTAIN ACCURATE CALL-PATH INFORMATION - A method for obtaining accurate call path information in a mixed-mode environment where interpreted methods and non-interpreted methods can call one another is disclosed. In one embodiment, such a method includes generating an event and recording it in a buffer when an interpreted method calls an interpreted method. The method also generates an event and records it in the buffer when an interpreted method calls a non-interpreted method. The method further generates an event and records it in the buffer when a non-interpreted method calls an interpreted method. The method refrains from generating an event when a non-interpreted method calls a non-interpreted method. A corresponding apparatus and computer program product are also disclosed. | 09-19-2013 |
20130247018 | EFFICIENT INTERPRETER PROFILING TO OBTAIN ACCURATE CALL-PATH INFORMATION - A method for obtaining accurate call path information in a mixed-mode environment where interpreted methods and non-interpreted methods can call one another is disclosed. In one embodiment, such a method includes generating an event and recording it in a buffer when an interpreted method calls an interpreted method. The method also generates an event and records it in the buffer when an interpreted method calls a non-interpreted method. The method further generates an event and records it in the buffer when a non-interpreted method calls an interpreted method. The method refrains from generating an event when a non- interpreted method calls a non-interpreted method. A corresponding apparatus and computer program product are also disclosed. | 09-19-2013 |
20140325492 | SELECTIVE SPECULATIVE CLASS-BASED OPTIMIZATION - A method, apparatus, and/or computer program product performs selective speculative class-based optimization through the use of a type propagation analysis of class. Responsive to a determination that the type of class is not a fixed type, a determination is made as to whether the class is sub-classed. Responsive to a determination the class is not sub-classed, a virtual synthetic property method is created. The virtual synthetic property method is accommodated in an enhanced java virtual machine using a stack frame type. The stack frame type has associated metadata for throwing an exception and an invisibility property. The virtual synthetic property method, along with a virtual guard, is inlined, and a slow path is created. The slow path handles executions of the virtual synthetic property method when sub-classes of the class, which override an implementation of the virtual synthetic property method, are loaded in the future. | 10-30-2014 |
20140325493 | SELECTIVE SPECULATIVE CLASS-BASED OPTIMIZATION - A method, apparatus, and/or computer program product performs selective speculative class-based optimization through the use of a type propagation analysis of class. Responsive to a determination that the type of class is not a fixed type, a determination is made as to whether the class is sub-classed. Responsive to a determination the class is not sub-classed, a virtual synthetic property method is created. The virtual synthetic property method is accommodated in an enhanced java virtual machine using a stack frame type. The stack frame type has associated metadata for throwing an exception and an invisibility property. The virtual synthetic property method, along with a virtual guard, is inlined, and a slow path is created. The slow path handles executions of the virtual synthetic property method when sub-classes of the class, which override an implementation of the virtual synthetic property method, are loaded in the future. | 10-30-2014 |