Abstract: Techniques are disclosed for managing vector element ordering. One technique includes receiving an assembler command from a source file, wherein the assembler command indicates a vector element order for one or more subsequent machine instructions in the source file. The technique includes determining whether the vector element order comprises a big-endian (BE) order or a little-endian (LE) order. If the vector element order comprises a BE order, the technique includes assembling one or more subsequent machine instructions and placing the machine instructions in a BE section of a file. If the vector element order comprises a LE order, the technique includes assembling one or more subsequent machine instructions and placing the machine instructions in a LE section of the file.

Abstract: A transactional memory system salvages a hardware lock elision (HLE) transaction. A processor of the transactional memory system, based on a detection of a pending point-of-failure in a code region during HLE transactional execution, stops HLE transactional execution prior to the pending point-of-failure in the code region. The processor, based on information about a lock elided, commits a speculative state of the stopped HLE transactional execution that is stored, at least in part, in a gathering store cache. The processor starts non-transactional execution at the point of failure in the code region.

Abstract: Method and apparatus for managing memory is disclosed herein. In one embodiment, the method includes specifying a first load-monitored region within a memory, configuring a performance monitor to count object pointer accessed events associated with the first load-monitored region, executing a CPU instruction to load a pointer that points to a first location in the memory, responsive to determining that the first location is within the first load-monitored region, triggering an object pointer accessed event, updating a count of object pointer accessed events in the performance monitor, and performing garbage collection on the first load-monitored region based on the count of object pointer accessed events.

Abstract: Embodiments relate to configurable processor interrupts. An aspect includes sending, by an application to supervisor software in a computer system, a request, the request including a plurality of exception types to be handled by the application. Another aspect includes determining, by the supervisor software, a subset of the plurality of exception types for which to approve handling by the application. Yet another aspect includes sending a response from the supervisor software to the application notifying the application of the subset of exception types.

Abstract: Method and apparatus for managing memory is disclosed herein. In one embodiment, the method includes specifying a first load-monitored region within a memory, configuring a performance monitor to count object pointer accessed events associated with the first load-monitored region, executing a CPU instruction to load a pointer that points to a first location in the memory, responsive to determining that the first location is within the first load-monitored region, triggering an object pointer accessed event, updating a count of object pointer accessed events in the performance monitor, and performing garbage collection on the first load-monitored region based on the count of object pointer accessed events.

Abstract: Throttling execution in a transaction operating in a processor configured to execute memory instructions out-of-program-order in a pipelined processor, wherein memory instructions are instructions for accessing operands in memory. Included is executing instructions of a transaction. Also included is determining whether the transaction is in throttling mode and based on determining that a transaction is in throttling mode, executing memory instructions in-program-order and dynamically prefetching memory operands of memory instructions.

Abstract: An instruction stream includes a transactional code region. The transactional code region includes a latent modification instruction (LMI), a next sequential instruction (NSI) following the LMI, and a set of target instructions following the NSI in program order. Each target instruction has an associated function, and the LMI at least partially specifies a substitute function for the associated function. A processor executes the LMI, the NSI, and at least one of the target instructions, employing the substitute function at least partially specified by the LMI. The LMI, the NSI, and the target instructions may be executed by the processor in sequential program order or out of order.

Abstract: An instruction stream includes a transactional code region. The transactional code region includes a latent modification instruction (LMI), a next sequential instruction (NSI) following the LMI, and a set of target instructions following the NSI in program order. Each target instruction has an associated function, and the LMI at least partially specifies a substitute function for the associated function. A processor executes the LMI, the NSI, and at least one of the target instructions, employing the substitute function at least partially specified by the LMI. The LMI, the NSI, and the target instructions may be executed by the processor in sequential program order or out of order.

Abstract: Prevention of a prefetch memory operation from causing a transaction to abort. A local processor receives a prefetch request from a remote processor. A processor determines whether the prefetch request conflicts with a transaction of the local processor. A processor responds to at least one of i) a determination that the local processor has no transaction, and ii) a determination that the prefetch request does not conflict with a transaction by providing a requested prefetch data by providing a requested prefetch data. A processor responds to a determination that the prefetch request conflicts with a transaction by suppressing a processing of the prefetch request.

Abstract: A higher level shared cache of a hierarchical cache of a multi-processor system utilizes transaction identifiers to manage memory conflicts in corresponding transactions. The higher level cache is shared with two or more processors. Transaction indicators are set in the higher level cache corresponding to the cache lines being accessed. The transaction aborts if a memory conflict with the transaction's cache lines from another transaction is detected.

Abstract: Improving the tracking of read sets and write sets associated with cache lines of a transaction in a pipelined processor executing memory instructions having the read sets and write sets associated with the cache lines is provided. Included is active read set and write set cache indicators associated with the memory operation of executing memory instructions and associated with a recovery pool based on memory instructions being not-speculative are updated when the memory instruction is not-newer in program order than an un-resolved branch instruction. Based on encountering a speculative branch instruction in the processor pipeline, a representation of the active read sets and write sets is copied to the recovery pool. Based on completing the speculative branch instruction, updating the active read sets and write sets from the representations copied to the recovery pool associated with the branch instruction upon a detection of a misprediction.

Abstract: Prevention of a prefetch memory operation from causing a transaction to abort. A local processor receives a prefetch request from a remote processor. A processor determines whether the prefetch request conflicts with a transaction of the local processor. A processor responds to at least one of i) a determination that the local processor has no transaction, and ii) a determination that the prefetch request does not conflict with a transaction by providing a requested prefetch data by providing a requested prefetch data. A processor responds to a determination that the prefetch request conflicts with a transaction by suppressing a processing of the prefetch request.

Abstract: In an approach for resolving terminated transactions in a transactional memory environment, a processor initiates a hardware transaction in a computing environment, wherein the hardware transaction accesses a memory location, and wherein the hardware transaction includes a transaction begin indicator and a transaction end indicator. A processor detects a conflicting access of the memory location while executing the hardware transaction. A processor aborts the hardware transaction based on the conflicting access of the memory location. Hardware determines that the conflicting access of the memory location is a transient condition. A processor reinitiates the hardware transaction.

Abstract: Embodiments relate to optimizing an indirect call function. A compiler is provided to identify potential target functions and indicate the potential target functions in the program code. Additionally, the compiler determines and indicates in the program code that the function pointer value resulting from a non-call reference of a function symbol is solely used to perform indirect calls in the same module. A linker can read the indication the compiler made in the program code and optimize the indirect call function.

Abstract: Determining, by a processor having a cache, if data in the cache is to be monitored for cache coherency conflicts in a transactional memory (TM) environment. A processor executes a TM transaction, that includes the following. Executing a memory data access instruction that accesses an operand at an operand memory address. Based on either a prefix instruction associated with the memory data access instruction, or an operand tag associated with the operand of the memory data access instruction, determining whether a cache entry having the operand is to be marked for monitoring for cache coherency conflicts while the processor is executing the transaction. Based on determining that the cache entry is to be marked for monitoring for cache coherency conflicts while the processor is executing the transaction, marking the cache entry for monitoring for conflicts.

Abstract: A method and associated computer program product are disclosed for generating an executable file from an object file, the object file being associated with an architecture having a predefined calling convention designating one or more call-clobbered registers. The method comprises identifying, from a first annotation included in the object file with a function call instruction, at least one restore instruction that follows the function call instruction, the function call instruction associated with a predefined function of the object file. The at least one restore instruction corresponds to at least one of the one or more call-clobbered registers. The method further comprises determining, based on at least a first list of registers that are referenced by the predefined function, the first list being included in the object file, whether to eliminate the at least one restore instruction.

Abstract: A method and associated computer program product are disclosed for generating an object file for subsequent linking by a linker. The object file comprises a function that references a table of contents (TOC) pointer register. The method comprises generating, in the object file, at least one first annotation that identifies at least one instruction of the function. The at least one instruction has an eliminable reference to the TOC pointer register. The first annotation configures the linker to determine, during the subsequent linking of the object file and based on the at least one first annotation, whether to eliminate the eliminable reference.

Abstract: A method and associated computer program product are disclosed for generating an object file for subsequent linking by a linker. The method comprises inserting at least one save instruction before a function call instruction and at least one restore instruction after the function call instruction, the at least one save instruction and the least one restore instruction corresponding to one or more call-clobbered registers. The method further comprises generating a first list of registers that are referenced by the function. The function call instruction includes a first annotation referencing the restore instruction, and the restore instruction includes a second annotation referencing the save instruction. The first and second annotations configure the linker to determine whether to eliminate the save instruction and the restore instruction corresponding to at least one of the one or more call-clobbered registers.

Abstract: A method and associated computer program product are disclosed for generating an executable file from an object file comprising a function that references a table of contents (TOC) pointer register. The method comprises identifying, based on at least one first annotation included in the object file, at least one instruction of the function having an eliminable reference to the TOC pointer register, and determining, during a linking of the object file and based on the at least one first annotation, whether to eliminate the eliminable reference.

Abstract: Atomically accumulating memory updates in a computer system configured with an accumulator that is memory mapped. The accumulator includes an accumulator memory and an accumulator queue and is configured to communicatively couple to a processor. Included is receiving from the processor, by the accumulator, an accumulation request. The accumulation request includes an accumulation operation identifier and data. Based on determining, by the accumulator, that the accumulator can immediately process the request, immediately processing the request. Processing the request includes atomically updating a value in the accumulator memory, by the accumulator, based on the operation identifier and data of the accumulation request. Based on determining, by the accumulator, that the accumulator is actively processing another accumulation request, queuing, by the accumulator, the accumulation request for later processing.