451 results about "Data dependence" patented technology

A determination can be made of bow changes to underlying data affect the value of objects. Examples of applications are: caching dynamic Web pages; client-server applications whereby a server sending objects (which are changing all the time) to multiple clients can track which versions are sent to which clients and how obsolete the versions are; and any situation where it is necessary to maintain and uniquely identify several versions of objects, update obsolete objects, quantitatively assess how different two versions of the same object are, and/or maintain consistency among a set of objects. A directed graph called an object dependence graph, may be used to represent the data dependencies between objects. Another aspect is constructing and maintaining objects to associate changes in remote data with cached objects. If data in a remote data source changes, database change notifications are used to "trigger" a dynamic rebuild of associated objects. Thus, obsolete objects can be dynamically replaced with fresh objects. The objects can be complex objects, such as dynamic Web pages or compound-complex objects, and the data can be underlying data in a database. The update can include either storing a new version of the object in the cache; or deleting an object from the cache. Caches on multiple servers can also be synchronized with the data in a single common database. Updated information, whether new pages or delete orders, can be broadcast to a set of server nodes, permitting many systems to simultaneously benefit from the advantages of prefetching and providing a high degree of scaleability.

Loop allocation for optimizing compilers includes the generation of a program dependence graph for a source code segment. Control dependence graph representations of the nested loops, from innermost to outermost, are generated and data dependence graph representations are generated for each level of nested loop as constrained by the control dependence graph. An interference graph is generated with the nodes of the data dependence graph. Weights are generated for the edges of the interference graph reflecting the affinity between statements represented by the nodes joined by the edges. Nodes in the interference graph are given weights reflecting resource usage by the statements associated with the nodes. The interference graph is partitioned using a profitability test based on the weights of edges and nodes and on a correctness test based on the reachability of nodes in the data dependence graph. Code is emitted based on the partitioned interference graph.

When a processor executes a memory operation instruction by means of data dependence speculative execution, a speculative execution result history table which stores history information concerning success/failure results of the speculative execution of memory operation instructions of the past is referred to and thereby whether the speculative execution will succeed or fail is predicted. In the prediction, the target address of the memory operation instruction is converted by a hash function circuit into an entry number of the speculative execution result history table (allowing the existence of aliases), and an entry of the table designated by the entry number is referred to. If the prediction is “success”, the memory operation instruction is executed in out-of-order execution speculatively (with regard to data dependence relationship between the instructions). If the prediction is “failure”, the speculative execution is canceled and the memory operation instruction is executed later in the program order non-speculatively. Whether the speculative execution of the memory operation instructions has succeeded or failed is judged by detecting the data dependence relationship between the memory operation instructions, and the speculative execution result history table is updated taking the judgment into account.

The invention discloses a method for extracting a malicious code behavior characteristic, which belongs to the technical field of network security. The method comprises the following steps of: 1) running a malicious code and extracting executive information of the malicious code, wherein the executive information comprises an executive instruction sequence and a behavior sequence of the maliciouscode; 2) constructing a control dependence graph and a data dependence graph for executing the code according to the executive information; 3) comparing relevance of the control dependence graph and the data dependence graph and recording related relevance information; and 4) comparing the control dependence graphs and the data dependence graphs of different malicious codes and extracting characteristic dependency of each type of samples according to similarity clustering. Compared with the prior art, the method has the characteristics of complete information extraction, high anti-interference performance, certain applicability to varieties of a single sample characteristic, small-sized characteristic library and wide application range.

A method for analyzing an original program to check an affected part by weaving an aspect and presenting the analysis result. An analysis device has an analysis processing portion for inputting a program based on aspect oriented programming, and acquiring data dependence information and control dependence information in the input program. A influence tracking portion tracks the data dependence and the control dependence acquired by the analysis processing portion starting from a position of weaving an aspect in the program, and searching a propagation path of the influence due the aspect weaving. A display control detects and displays a part undergoing the aspect weaving influence, based on the result of parsing by the analysis processing portion and information about the propagating path obtained by the influence tracking portion.

The invention discloses a parallel transaction execution method based on a blockchain. Firstly, a data unit on the datachain is subjected to index numbering, the parallel transaction of a user needs to provide a data index which needs to be read and written for transaction execution in addition to basic transaction contents. The serial transaction of the user only needs to provide the basic transaction contents. A node arranges parallel processing according to the data dependency relationship of the parallel transaction, and the transaction which can not carry out concurrence and the serial transaction can be executed in sequence.

A circuit (10) for multiplying two floating point operands (A and C) while adding or subtracting a third floating point operand (B) removes latency associated with normalization and rounding from a critical speed path for dependent calculations. An intermediate representation of a product and a third operand are selectively shifted to facilitate use of prior unnormalized dependent resultants. Logic circuitry (24, 42) implements a truth table for determining when and how much shifting should be made to intermediate values based upon a resultant of a previous calculation, upon exponents of current operands and an exponent of a previous resultant operand. Normalization and rounding may be subsequently implemented, but at a time when a new cycle operation is not dependent on such operations even if data dependencies exist.

The invention provides a program conversion apparatus which performs parallelization for a multi-thread microprocessor on an intermediate program level. A parallelization apparatus of the program conversion apparatus includes a fork spot determination section, a register allocation section and an instruction reordering section. The fork spot determination section determines a fork spot and a fork system based on a result of a register allocation trial performed by the register allocation section, the number of spots at which memory data dependence is present, and branching probabilities and a data dependence occurrence frequency obtained from a profile information file. The instruction reordering section reorders instructions preceding to and succeeding the FORK instruction in accordance with the determination.

Methods and apparatus for data-dependent mass spectrometric MS/MS or MSⁿ analysis are disclosed. The methods may include determination of the charge state of an ion species of interest, followed by automated selection of a dissociation type (e.g., CAD, ETD, or ETD followed by a non-dissociative charge reduction or collisional activation) based at least partially on the determined charge state. The ion species of interest is then dissociated in accordance with the selected dissociation type, and an MS/MS or MSⁿ spectrum of the resultant product ions may be acquired.

A system for tracking memory dependencies includes a speculative thread management unit, which uses a bit vector to record and encode addresses of memory access. The speculative thread management unit includes a hashing unit that partitions the addresses into a load hash set and a store hash set, a load hash set unit for storing the load hash set, a store hash set unit for storing the store hash set, and a data dependence checking unit that checks data dependence when a thread completes, by comparing a load hash set of the thread to a store hash set of other threads.

The invention discloses a realization method for the parallelization of the single-threading program based on the analysis of data flow. In the invention, by analyzing the data dependence among the instructions in the single-thread program, the single-threading program is transformed to a multi-threading program, the dependence among the instructions in the single-thread program includes a data dependence and a control dependence, wherein the control dependence is a dependence for the control condition value and a special data dependence. In the process of thread analyzing, the invention can take regard of the balance of the thread communication expense and the thread after analyzing. The invention has the advantage that the different parts of the single-threading program are executed in parallel, thus reducing the program executing time and improving the program executing efficiency. The method for the parallelization of the single-threading program is in particular suitable for the current multi-core structure.

The invention discloses a memory access abnormity detecting method and a memory access abnormity detecting device. The memory access abnormity detecting method comprises the following steps of checking source codes and analyzing the morphology, the grammar and the semanteme of the source codes to generate a control flow diagram, a data dependence diagram, a first list file and a second list file; establishing a global function invocation diagram of the source codes according to the control flow diagram; performing matching detection on dynamic memory allocation of the source codes according to the global function invocation diagram, the second list file and the data dependence diagram; and establishing a virtual executing platform; and extracting an executing path according to the first list file, the control flow diagram and the data dependence diagram so as to detect memory leakage caused by dynamic memory allocation and memory access violation during running of a program. Memory access abnormity in the source codes can be sufficiently dug by analyzing the first list file, the second list file, the control flow diagram, the data dependence diagram and the global function invocation diagram, establishing the virtual executing platform and extracting the executing path, and the memory access abnormity can be detected efficiently.

The invention relates to the field of high-performance computing automatic parallelization, in particular to an automatic vectorizing method for heterogeneous SIMD expansion components. The automatic vectorizing method is suitable for the heterogeneous SIMD expansion components with different vector quantity lengths and different vector quantity instruction sets, a set of virtual instruction sets are designed, and an input C and a Fortran program can be converted into an intermediate representation of virtual instructions under an automatic vectorizing unified framework. The virtual instruction sets are automatically converted into vectorizing codes for the heterogeneous SIMD expansion components through solving virtualization of the vector quantity lengths and solving virtualization of the instruction sets so that a programmer can be free from complex manual vectorizing coding work. The vectorizing method is combined with relative optimizing methods, vectorizing recognition is carried out from different granularities, mixing parallelism of a circulation level and a basic block level is explored to the greatest extent through conventional optimization and invocation point optimization, the redundancy optimization is carried out on generated codes through the analysis about striding data dependence of a basic block, and executing efficiency of a program is effectively improved.

A mechanism is provided for reordering bus transactions to increase bus utilization in a computer system in which a split-transaction bus is bridged to a single-envelope bus. In one embodiment, both masters and slaves are ordered, simplifying implementation. In another embodiment, the system is more loosely coupled with only masters being ordered. Greater bus utilization is thereby achieved. To avoid deadlock, transactions begun on the split-transaction bus are monitored. When a combination of transactions would, if a predetermined further transaction were to begin, result in deadlock, this condition is detected. In the more tightly coupled system, the predetermined further transaction, if it is requested, is refused, thereby avoiding deadlock. In the more loosely-coupled system, the flexibility afforded by unordered slaves is taken advantage of to, in the typical case, reorder the transactions and avoid deadlock without killing any transaction. Where a data dependency exists that would prevent such reordering, the further transactions is killed as in the more tightly-coupled embodiment. Data dependencies are detected in accordance with address-coincidence signals generated by slave devices on a cache-line basis. In accordance with a further optimization, at least one slave device (e.g., DRAM) generates page-coincidence bits. When two transactions to the slave device are to the same address page, the transactions are reordered if necessary to ensure that they are executed one after another without any intervening transaction. Latency of the slave is thereby reduced.

The invention discloses a progressive distribution type encoding and decoding method for a multispectral image. In the method, each band image is directly and independently encoded at an encoding end,and data dependence is only excavated at a decoding end, therefore, the complexity of data calculation can be transferred from the encoding end with resource constraint to the decoding end with richresources so as to optimally utilize resources of a system and be suitable for a remote sensing satellite. The invention also discloses a distribution type encoding and decoding device for a multispectral image. A module which is used for excavating the data dependence is arranged at the decoding end, and therefore, the encoding end is simplified to the maximum to enable the system to be more reasonable. The invention has the advantages of low encoding complexity, high compression efficiency, strong error resilience ability and progressive transfer characteristic and is suitable for lossless compression or nearly lossless compression of the multispectral image, in particular to an image compression application on the satellite.

A method of analyzing data from a mass spectrometer for a data dependent acquisition is described. In an embodiment of this method, mass spectral scans are taken of a sample eluted from a liquid chromatography column. An extracted ion chromatogram (XIC) is then created for each m/z data point of the mass spectral scans and the XIC for each m/z data point are correlated to a model function, such as a monotonically increasing function, or the first half of a gaussian function, to obtain a XIC correlation value. A weighting function is then applied to the XIC correlation value to obtain a current weighted intensity. The current weighted intensity for each m/z point is used to reconstruct a weighted mass spectrum, which is then used to make a real-time decision for the data dependent acquisition. In an embodiment, the data dependent acquisition is the performance of tandem mass spectrometry. Embodiments of the invention also describe a sample processing apparatus for the data dependent acquisition and a computer readable medium that provides instructions to the sample processing apparatus to perform the method described above.

A system for time-ordered execution of load instructions. More specifically, the system enables just-in-time delivery of data requested by a load instruction. The system consists of a processor, an L1 data cache with corresponding L1 cache controller, and an instruction processor. The instruction processor manipulates a plurality of architected time dependency fields of a load instruction to create a plurality of dependency fields. The dependency fields holds a relative dependency value which is utilized to order the load instruction in a Relative Time-Ordered Queue (RTOQ) of the L1 cache controller. The load instruction is sent from RTOQ to the L1 data cache at a particular time so that the data requested is loaded from the L1 data cache at the time specified by one of the dependency fields. The dependency fields are prioritized so that the cycle corresponding to the highest priority field which is available is utilized.

The invention discloses a cluster compression method based on data similarity. By analyzing file data, structural characteristic vector of characteristic fingerprint is extracted from files to calculate the data similarity; files are input in cluster by utilizing a graph partitioning method with a restricted condition, so that a plurality of categories in even sizes are formed; and finally, compression is respectively performed on each category by utilizing compression methods, such as BMCOM, so as to remove the redundant data in category interior. The invention adopts a clustering method based on data sampling; and key data with a high condensability serves as sample data. Firstly, clustering is performed on the sample data; then, the remaining data is classified through a marriage stabilizing method, thereby improving clustering efficiency under a condition that the compressing effect is not reduced. As a compressing and filing method, the invention can be applied to a distributed storage system, so that the problem of uneven data dependence and load in the prior method can be solved.