Patent application number | Description | Published |
20090083569 | Generating a Local Clock Domain Using Dynamic Controls - A method for generating a local clock domain within an operation includes steps of: receiving a clock frequency measurement for a slow portion of logic within the operation; generating a local signal to indicate commencement of the operation and to function as a clock gating signal; latching the clock gating signal to a selected cycle; generating clock domain controls based on the clock gating signal such that the operation times its commencement on the selected cycle; and propagating the clock gating signal in ungated latches for a number of cycles, such that a second operation is restricted from being launched until the operation completes. | 03-26-2009 |
20100325385 | DETECTION OF ZERO ADDRESS EVENTS IN ADDRESS FORMATION - One or more registers used to form an address usable in accessing storage are examined to determine if a zero address event has occurred in forming the address. In response to an indication that a zero address event has occurred in address formation, an alert is provided to the program using the address to access storage. | 12-23-2010 |
20110145550 | NON-QUIESCING KEY SETTING FACILITY - A non-quiescing key setting facility is provided that enables manipulation of storage keys to be performed without quiescing operations of other processors of a multiprocessor system. With this facility, a storage key, which is accessible by a plurality of processors of the multiprocessor system, is updated absent a quiesce of operations of the plurality of processors. Since the storage key is updated absent quiescing of other operations, the storage key may be observed by a processor as having one value at the start of an operation performed by the processor and a second value at the end of the operation. A mechanism is provided to enable the operation to continue, avoiding a fatal exception. | 06-16-2011 |
20110153986 | PREDICTING AND AVOIDING OPERAND-STORE-COMPARE HAZARDS IN OUT-OF-ORDER MICROPROCESSORS - A method and information processing system manage load and store operations executed out-of-order. At least one of a load instruction and a store instruction is executed. A determination is made that an operand store compare hazard has been encountered. An entry within an operand store compare hazard prediction table is created based on the determination. The entry includes at least an instruction address of the instruction that has been executed and a hazard indicating flag associated with the instruction. The hazard indicating flag indicates that the instruction has encountered the operand store compare hazard. When a load instruction is associated with the hazard indicating flag the load instruction becomes dependent upon all store instructions associated with a substantially similar flag. | 06-23-2011 |
20110153991 | DUAL ISSUING OF COMPLEX INSTRUCTION SET INSTRUCTIONS - A system and method for issuing a processor instruction to multiple processing sections arranged in an out-of-order processing pipeline architecture. The multiple processing sections include a first execution unit with a pipeline length and a second execution unit operating upon data produced by the first execution unit. An instruction issue unit accepts a complex instruction that is cracked into respective micro-ops for the first execution unit and the second execution unit. The instruction issue unit issues the first micro-op to the first execution unit to produce intermediate data. The instruction issue unit then delays for a time period corresponding to the processing pipeline length of the first execution unit. After the delay, a second micro-op is issued to the second execution unit. | 06-23-2011 |
20110154116 | PREDICTING AND AVOIDING OPERAND-STORE-COMPARE HAZARDS IN OUT-OF-ORDER MICROPROCESSORS - A method and information processing system manage load and store operations executed out-of-order. At least one of a load instruction and a store instruction is executed. A determination is made that an operand store compare hazard has been encountered. An entry within an operand store compare hazard prediction table is created based on the determination. The entry includes at least an instruction address of the instruction that has been executed and a hazard indicating flag associated with the instruction. The hazard indicating flag indicates that the instruction has encountered the operand store compare hazard. When a load instruction is associated with the hazard indicating flag the load instruction becomes dependent upon all store instructions associated with a substantially similar flag. | 06-23-2011 |
20110154298 | COLLECTING COMPUTER PROCESSOR INSTRUMENTATION DATA - A system and method for collecting instrumentation data in a processor with a pipelined instruction execution stages arranged in an out-of-order execution architecture. One instruction group in a Global Completion Table is marked as a tagged group. Instrumentation data is stored for processing stages processing instructions associated with the tagged group. Sample signal pulses trigger a determination of whether the tagged group is the next-to-complete instruction group. When the sample pulse occurs at a time when the tagged group is the next-to-complete group, the instrumentation data is written as an output. Instrumentation data present during sample pulses that occur when the tagged group is not the next-to-complete group is optionally discarded. Sample pulses are generated at a rate equal to the desired sample rate times the number of groups in the global completion table to better ensure occurrence of a next-to-complete tagged group. | 06-23-2011 |
20110185158 | HISTORY AND ALIGNMENT BASED CRACKING FOR STORE MULTIPLE INSTRUCTIONS FOR OPTIMIZING OPERAND STORE COMPARE PENALTIES - Store multiple instructions are managed based on previous execution history and their alignment. At least one store multiple instruction is detected. A flag is determined to be associated with the at least one store multiple instruction. The flag indicates that the at least one store multiple instruction has previously encountered an operand store compare hazard. The at least one store multiple instruction is organized into a set of unit of operations. The set of unit of operations is executed. The executing avoids the operand store compare hazard previously encountered by the at least one store multiple instruction. | 07-28-2011 |
20110202747 | INSTRUCTION LENGTH BASED CRACKING FOR INSTRUCTION OF VARIABLE LENGTH STORAGE OPERANDS - A method, information processing system, and computer program product manage variable operand length instructions. At least one variable operand length instruction is received. The at least one variable operand length instruction is analyzed. A length of at least one operand in the variable operand length instruction is identified based on the analyzing. The at least one variable operand length instruction is organized into a set of unit of operations. The set of unit of operations are executed. The executing increases one or more performance metrics of the at least one variable operand length instruction. | 08-18-2011 |
20110202748 | LOAD PAIR DISJOINT FACILITY AND INSTRUCTION THEREFORE - A Load/Store Disjoint instruction, when executed by a CPU, accesses operands from two disjoint memory locations and sets condition code indicators to indicate whether or not the two operands appeared to be accessed atomically by means of block-concurrent interlocked fetch with no intervening stores to the operands from other CPUs. In a Load Pair Disjoint form of the instruction, the accesses are loads and the disjoint data is stored in general registers. | 08-18-2011 |
20110276764 | CRACKING DESTRUCTIVELY OVERLAPPING OPERANDS IN VARIABLE LENGTH INSTRUCTIONS - A method, information processing system, and computer program product manage computer executable instructions. At least one machine instruction for execution is received. The at least one machine instruction is analyzed. The machine instruction is identified as a predefined instruction for storing a variable length first operand in a memory location. Responsive to this identification and based on fields of the machine instruction, a relative location of a variable length second operand of the instruction with location of the first operand is determined. Responsive to the relative location having the predefined relationship, a first cracking operation is performed. The first cracking operation cracks the instruction into a first set of micro-ops (Uops) to be executed in parallel. The second set of Uops is for storing a first plurality of first blocks in the first operand. Each of said first block to be stored are identical. The first set Uops are executed. | 11-10-2011 |
20120204010 | NON-QUIESCING KEY SETTING FACILITY - A non-quiescing key setting facility is provided that enables manipulation of storage keys to be performed without quiescing operations of other processors of a multiprocessor system. With this facility, a storage key, which is accessible by a plurality of processors of the multiprocessor system, is updated absent a quiesce of operations of the plurality of processors. Since the storage key is updated absent quiescing of other operations, the storage key may be observed by a processor as having one value at the start of an operation performed by the processor and a second value at the end of the operation. A mechanism is provided to enable the operation to continue, avoiding a fatal exception. | 08-09-2012 |
20130117546 | Load Pair Disjoint Facility and Instruction Therefore - A Load/Store Disjoint instruction, when executed by a CPU, accesses operands from two disjoint memory locations and sets condition code indicators to indicate whether or not the two operands appeared to be accessed atomically by means of block-concurrent interlocked fetch with no intervening stores to the operands from other CPUs. In a Load Pair Disjoint form of the instruction, the accesses are loads and the disjoint data is stored in general registers. | 05-09-2013 |
20130246762 | INSTRUCTION TO LOAD DATA UP TO A DYNAMICALLY DETERMINED MEMORY BOUNDARY - A Load to Block Boundary instruction is provided that loads a variable number of bytes of data into a register while ensuring that a specified memory boundary is not crossed. The boundary is dynamically determined based on a specified type of boundary and one or more characteristics of the processor executing the instruction, such as cache line size or page size used by the processor. | 09-19-2013 |
20130246763 | INSTRUCTION TO COMPUTE THE DISTANCE TO A SPECIFIED MEMORY BOUNDARY - A Load Count to Block Boundary instruction is provided that provides a distance from a specified memory address to a specified memory boundary. The memory boundary is a boundary that is not to be crossed in loading data. The boundary may be specified a number of ways, including, but not limited to, a variable value in the instruction text, a fixed instruction text value encoded in the opcode, or a register based boundary; or it may be dynamically determined. | 09-19-2013 |
20130246764 | INSTRUCTION TO LOAD DATA UP TO A SPECIFIED MEMORY BOUNDARY INDICATED BY THE INSTRUCTION - A Load to Block Boundary instruction is provided that loads a variable number of bytes of data into a register while ensuring that a specified memory boundary is not crossed. The boundary may be specified a number of ways, including, but not limited to, a variable value in the instruction text, a fixed instruction text value encoded in the opcode, or a register based boundary. | 09-19-2013 |
20130318330 | PREDICTING AND AVOIDING OPERAND-STORE-COMPARE HAZARDS IN OUT-OF-ORDER MICROPROCESSORS - A method and information processing system manage load and store operations that can be executed out-of-order. At least one of a load instruction and a store instruction is executed. A determination is made that an operand store compare hazard has been encountered. An entry within an operand store compare hazard prediction table is created based on the determination. The entry includes at least an instruction address of the instruction that has been executed and a hazard indicating flag associated with the instruction. The hazard indicating flag indicates that the instruction has encountered the operand store compare hazard. When a load instruction is associated with the hazard indicating flag, the load instruction becomes dependent upon all store instructions associated with a substantially similar hazard indicating flag. | 11-28-2013 |
20130326256 | GENERATING MONOTONICALLY INCREASING TOD VALUES IN A MULTIPROCESSOR SYSTEM - Generating monotonically increasing time-of-day values in a multiprocessor system is provided. Synchronization impulses are received by a processor of the multiprocessor system, and an execution of a read instruction of a time-of-day value within a processor of the processors is refused, if the execution of the read instruction of the time-of-day value is requested after a predefined time after a synchronization impulse of the synchronization impulses, and if a trigger signal, indicative of new data received by a related memory system, has been received after the predefined time, wherein the memory system is external to the processor. | 12-05-2013 |
20130339330 | FACILITATING TRANSACTION COMPLETION SUBSEQUENT TO REPEATED ABORTS OF THE TRANSACTION - Processing of transactions within a computing environment is facilitated by taking actions to increase the chances of successfully executing a transaction. A counter is maintained that provides a count of how often a transaction has aborted. The counter increments the count each time the transaction is aborted, and it is reset to zero upon successful completion of the transaction or an interruption leading to no more re-executions of the transaction. If the count reaches a threshold value, then an interrupt is presented and transaction execution is unsuccessful. However, before the count reaches the threshold, a number of actions may be taken to increase the chances of successfully executing the transaction. These actions include actions to be performed within the processor executing the transaction, and/or actions to be performed against conflicting processors. | 12-19-2013 |
20130339562 | PROGRAM EVENT RECORDING WITHIN A TRANSACTIONAL ENVIRONMENT - A transaction is initiated within a computing environment, and based on detecting a program event recording event, an interrupt is presented for the transaction. Subsequent to the interrupt, one or more controls are set to inhibit presentation of another interrupt based on detecting another PER event. Thereafter, the transaction is re-executed and PER events detected during execution of the transaction are ignored. | 12-19-2013 |
20130339669 | NONTRANSACTIONAL STORE INSTRUCTION - A NONTRANSACTIONAL STORE instruction, executed in transactional execution mode, performs stores that are retained, even if a transaction associated with the instruction aborts. The stores include user-specified information that may facilitate debugging of an aborted transaction. | 12-19-2013 |
20130339690 | TRANSACTIONAL EXECUTION BRANCH INDICATIONS - Transactional execution branch indications are placed into one or more transaction diagnostic blocks when a transaction is aborted. Each branch indication specifies whether a branch was taken, as a result of executing a branch instruction within the transaction. As the transaction executes and a branch instruction is encountered, a branch indication is set in a vector indicating whether the branch was taken. Then, if the transaction aborts, the indicators are stored in one or more transaction diagnostic blocks providing a branch history usable in diagnosing the failure. | 12-19-2013 |
20130339703 | RESTRICTING PROCESSING WITHIN A PROCESSOR TO FACILITATE TRANSACTION COMPLETION - Processing of transactions within a computing environment is facilitated by taking actions to increase the chances of successfully executing a transaction. A counter is maintained that provides a count of how often a transaction has aborted. The counter increments the count each time the transaction is aborted, and it is reset to zero upon successful completion of the transaction or an interruption leading to no more re-executions of the transaction. If the count reaches a threshold value, then an interrupt is presented and transaction execution is unsuccessful. However, before the count reaches the threshold, a number of actions may be taken to increase the chances of successfully executing the transaction. These actions include actions to be performed within the processor executing the transaction, and/or actions to be performed against conflicting processors. | 12-19-2013 |
20130339705 | RANDOMIZED TESTING WITHIN TRANSACTIONAL EXECUTION - Task specific diagnostic controls are provided to facilitate the debugging of certain types of abort conditions. The diagnostic controls may be set to cause transactions to be selectively aborted, allowing a transaction to drive its abort handler routine for testing purposes. The controls include, for instance, a transaction diagnostic scope and a transaction diagnostic control. The transaction diagnostic scope indicates when the transaction diagnostic control is to be applied, and the transaction diagnostic control indicates whether transactions are to selectively aborted. | 12-19-2013 |
20130339706 | PROCESSOR ASSIST FACILITY - An operation is provided to signal a processor that action is to be taken to facilitate execution of a transaction that has aborted one or more times. The operation is specified within an instruction or is itself an instruction. The instruction is executed based on detecting an abort of the transactions, and includes a field indicating how many times the transaction has aborted. The processor uses this information to determine what action is to be taken. | 12-19-2013 |
20130339707 | SELECTIVELY CONTROLLING INSTRUCTION EXECUTION IN TRANSACTIONAL PROCESSING - Execution of instructions in a transactional environment is selectively controlled. A TRANSACTION BEGIN instruction initiates a transaction and includes controls that selectively indicate whether certain types of instructions are permitted to execute within the transaction. The controls include one or more of an allow access register modification control and an allow floating point operation control. | 12-19-2013 |
20130339708 | PROGRAM INTERRUPTION FILTERING IN TRANSACTIONAL EXECUTION - Program exception conditions cause a transaction to abort and typically result in an interruption in which the operating system obtains control. A program interruption filtering control is provided to selectively present the interrupt. That is, the interrupt from the program exception condition may or may not be presented depending at least on the program interruption filtering control and a transaction class associated with the program exception condition. The program interruption filtering control is provided by a TRANSACTION BEGIN instruction. | 12-19-2013 |
20130339709 | TRANSACTION ABORT INSTRUCTION - A TRANSACTION ABORT instruction is used to abort a transaction that is executing in a computing environment. The TRANSACTION ABORT instruction includes at least one field used to specify a user-defined abort code that indicates the specific reason for aborting the transaction. Based on executing the TRANSACTION ABORT instruction, a condition code is provided that indicates whether re-execution of the transaction is recommended. | 12-19-2013 |
20130339804 | TRANSACTION DIAGNOSTIC BLOCK - When an abort of a transaction occurs, a determination is made as to whether diagnostic information is to be stored in one or more transaction diagnostic blocks (TDBs). There are different types of transaction diagnostic blocks to accept diagnostic information depending on the type of abort and other considerations. As examples, there are a program-specified TDB in which information is stored if a valid TDB address is provided in a transaction begin instruction; a program interruption TDB, which is stored into when the program is aborted due to an interruption; and a program interception TDB, which is stored into when an abort results in an interception. | 12-19-2013 |
20130339960 | TRANSACTION BEGIN/END INSTRUCTIONS - A TRANSACTION BEGIN instruction and a TRANSACTION END instruction are provided. The TRANSACTION BEGIN instruction causes either a constrained or nonconstrained transaction to be initiated, depending on a field of the instruction. The TRANSACTION END instruction ends the transaction started by the TRANSACTION BEGIN instruction. | 12-19-2013 |
20130339961 | TRANSACTIONAL PROCESSING - A transaction is initiated via a transaction begin instruction. During execution of the transaction, the transaction may abort. If the transaction aborts, a determination is made as to the type of transaction. Based on the transaction being a first type of transaction, resuming execution at the transaction begin instruction, and based on the transaction being a second type, resuming execution at an instruction following the transaction begin instruction. Regardless of transaction type, resuming execution includes restoring one or more registers specified in the transaction begin instruction and discarding transactional stores. For one type of transaction, the nonconstrained transaction, the resuming includes storing information in a transaction diagnostic block. | 12-19-2013 |
20130339962 | TRANSACTION ABORT PROCESSING - A transaction executing within a computing environment ends prior to completion; i.e., execution is aborted. Pursuant to aborting execution, a hardware transactional execution CPU mode is exited, and one or more of the following is performed: restoring selected registers; committing nontransactional stores on abort; branching to a transaction abort program status word specified location; setting a condition code and/or abort code; and/or preserving diagnostic information. | 12-19-2013 |
20130346697 | MULTILEVEL CACHE SYSTEM - Fetching a cache line into a plurality of caches of a multilevel cache system. The multilevel cache system includes at least a first cache, a second cache on a next higher level and a memory, the first cache being arranged to hold a subset of information of the second cache, the second cache being arranged to hold a subset of information of a next higher level cache or memory if no higher level cache exists. A fetch request is sent from one cache to the next cache in the multilevel cache system. The cache line is fetched in a particular state into one of the caches, and in another state into at least one of the other caches. | 12-26-2013 |
20140115249 | Parallel Execution Mechanism and Operating Method Thereof - A thread priority control mechanism is provided which uses the completion event of the preceding transaction to raise the priority of the next transaction in the order of execution when the transaction status has been changed from speculative to non-speculative. In one aspect of the present invention, a thread-level speculation mechanism is provided which has content-addressable memory, an address register and a comparator for recording transaction footprints, and a control logic circuit for supporting memory synchronization instructions. This supports hardware transaction memory in detecting transaction conflicts. This thread-level speculation mechanism includes a priority up bit for recording an attribute operand in a memory synchronization instruction, a means for generating a priority up event when a thread wake-up event has occurred and the priority up bit is 1, and a means for preventing the CAM from storing the load/store address when the instruction is a non-transaction instruction. | 04-24-2014 |
20140115306 | Next Instruction Access Intent Instruction - Executing a Next Instruction Access Intent instruction by a computer. The processor obtains an access intent instruction indicating an access intent. The access intent is associated with an operand of a next sequential instruction. The access intent indicates usage of the operand by one or more instructions subsequent to the next sequential instruction. The computer executes the access intent instruction. The computer obtains the next sequential instruction. The computer executes the next sequential instruction, which comprises based on the access intent, adjusting one or more cache behaviors for the operand of the next sequential instruction. | 04-24-2014 |
20140129773 | HIERARCHICAL CACHE STRUCTURE AND HANDLING THEREOF - A hierarchical cache structure comprises at least one higher level cache comprising a unified cache array for data and instructions and at least two lower level caches, each split in an instruction cache and a data cache. An instruction cache and a data cache of a split second level cache are connected to a third level cache; and an instruction cache of a split first level cache is connected to the instruction cache of the split second level cache, and a data cache of the split first level cache is connected to the instruction cache and the data cache of the split second level cache. | 05-08-2014 |
20140129774 | HIERARCHICAL CACHE STRUCTURE AND HANDLING THEREOF - A hierarchical cache structure includes at least one real indexed higher level cache with a directory and a unified cache array for data and instructions, and at least two lower level caches, each split in an instruction cache and a data cache. An instruction cache of a split real indexed second level cache includes a directory and a corresponding cache array connected to the real indexed third level cache. A data cache of the split second level cache includes a directory connected to the third level cache. An instruction cache of a split virtually indexed first level cache is connected to the second level instruction cache. A cache array of a data cache of the first level cache is connected to the cache array of the second level instruction cache and to the cache array of the third level cache. A directory of the first level data cache is connected to the second level instruction cache directory and to the third level cache directory. | 05-08-2014 |
20140310475 | ATOMIC EXECUTION OVER ACCESSES TO MULTIPLE MEMORY LOCATIONS IN A MULTIPROCESSOR SYSTEM - A method and central processing unit supporting atomic access of shared data by a sequence of memory access operations. A processor status flag is reset. A processor executes, subsequent to the setting of the processor status flag, a sequence of program instructions with instructions accessing a subset of shared data contained within its local cache. During execution of the sequence of program instructions and in response to a modification by another processor of the subset of shared data, the processor status flag is set. Subsequent to the executing the sequence of program instructions and based upon the state of the processor status flag, either a first program processing or a second program processing is executed. In some examples the first program processing includes storing results data into the local cache and the second program processing includes discarding the results data. | 10-16-2014 |
20140380319 | ADDRESS TRANSLATION/SPECIFICATION FIELD FOR HARDWARE ACCELERATOR - Embodiments relate an address translation/specification (ATS) field. An aspect includes receiving a work queue entry from a work queue in a main memory by a hardware accelerator, the work queue entry corresponding to an operation of the hardware accelerator that is requested by user-space software, the work queue entry comprising a first ATS field that describes a structure of the work queue entry. Another aspect includes, based on determining that the first ATS field is consistent with the operation corresponding to the work queue entry and the structure of the work queue entry, executing the operation corresponding to the work queue entry by the hardware accelerator. Another aspect includes, based on determining that the first ATS field is not consistent with the operation corresponding to the work queue entry and the structure of the work queue entry, rejecting the work queue entry by the hardware accelerator. | 12-25-2014 |
20150020192 | ADDRESS TRANSLATION/SPECIFICATION FIELD FOR HARDWARE ACCELERATOR - Embodiments relate an address translation/specification (ATS) field. An aspect includes receiving a work queue entry from a work queue in a main memory by a hardware accelerator, the work queue entry corresponding to an operation of the hardware accelerator that is requested by user-space software, the work queue entry comprising a first ATS field that describes a structure of the work queue entry. Another aspect includes, based on determining that the first ATS field is consistent with the operation corresponding to the work queue entry and the structure of the work queue entry, executing the operation corresponding to the work queue entry by the hardware accelerator. Another aspect includes, based on determining that the first ATS field is not consistent with the operation corresponding to the work queue entry and the structure of the work queue entry, rejecting the work queue entry by the hardware accelerator. | 01-15-2015 |
20150032964 | HANDLING VIRTUAL MEMORY ADDRESS SYNONYMS IN A MULTI-LEVEL CACHE HIERARCHY STRUCTURE - Handling virtual memory address synonyms in a multi-level cache hierarchy structure. The multi-level cache hierarchy structure having a first level, L1 cache, the L1 cache being operatively connected to a second level, L2 cache split into a L2 data cache directory and a L2 instruction cache. The L2 data cache directory including directory entries having information of data currently stored in the L1 cache, the L2 cache being operatively connected to a third level, L3 cache. The first level cache is virtually indexed while the second and third levels are physically indexed. Counter bits are allocated in a directory entry of the L2 data cache directory for storing a counter number. The directory entry corresponds to at least one first L1 cache line. A first search is performed in the L1 cache for a requested virtual memory address, wherein the virtual memory address corresponds to a physical memory address tag at a second L1 cache line. | 01-29-2015 |
20150052336 | SELECTIVELY CONTROLLING INSTRUCTION EXECUTION IN TRANSACTIONAL PROCESSING - Execution of instructions in a transactional environment is selectively controlled. A TRANSACTION BEGIN instruction initiates a transaction and includes controls that selectively indicate whether certain types of instructions are permitted to execute within the transaction. The controls include one or more of an allow access register modification control and an allow floating point operation control. | 02-19-2015 |
20150052337 | SELECTIVELY CONTROLLING INSTRUCTION EXECUTION IN TRANSACTIONAL PROCESSING - Execution of instructions in a transactional environment is selectively controlled. A TRANSACTION BEGIN instruction initiates a transaction and includes controls that selectively indicate whether certain types of instructions are permitted to execute within the transaction. The controls include one or more of an allow access register modification control and an allow floating point operation control. | 02-19-2015 |