摘要:
Database processing using columns to present to a processing unit decompressed column data without changing the underlying row-based database architecture. For some embodiments, a database accelerator is used to efficiently process the columns of a database and output tuples to a processing unit's memory, such that the columns can be quickly processed (with the advantages of a column-based architecture) to create tuples of requested data, but without having to depart from a row-based architecture at the processing unit level or having decompressed data scattered throughout the processing unit's memory.
摘要:
Executing programs coded in an instruction set of a first computer on a computer of a second, different architecture. An operating system maintains an association between each one of a set of concurrent threads and a set of computer resources of the thread's context. Without modifying a pre-existing operating system of the computer, an entry exception is establishing to be raised on each entry to the operating system at a specified entry point or on a specified condition. The entry exception has an associated entry handler programmed to save a context of an interrupted thread and modify the thread context before delivering the modified context to the operating system. A resumption exception is established to be raised on each resumption from the operating system complementary to one of the specified entries. The resumption exception has an associated exit handler programmed to restore the context saved by a corresponding execution of the entry handler. The entry exception, exit exception, entry handler, and exit handler are cooperatively designed to maintain an association between a one of the threads and an extended context of the thread through a context change induced by the operating system, the extended context including resources of the computer associated with the thread beyond those resources whose association with the thread is maintained by the operating system.
摘要:
A computer. A processor pipeline alternately executes instructions coded for first and second different computer architectures or coded to implement first and second different processing conventions. A memory stores instructions for execution by the processor pipeline, the memory being divided into pages for management by a virtual memory manager, a single address space of the memory having first and second pages. A memory unit fetches instructions from the memory for execution by the pipeline, and fetches stored indicator elements associated with respective memory pages of the single address space from which the instructions are to be fetched. Each indicator element is designed to store an indication of which of two different computer architectures and/or execution conventions under which instruction data of the associated page are to be executed by the processor pipeline. The memory unit and/or processor pipeline recognizes an execution flow from the first page, whose associated indicator element indicates the first architecture or execution convention, to the second page, whose associated indicator element indicates the first architecture or execution convention. In response to the recognizing, a processing mode of the processor pipeline or a storage content of the memory adapts to effect execution of instructions in the architecture and/or under the convention indicated by the indicator element corresponding to the instruction's page.
摘要:
A computer. A processor pipeline alternately executes instructions coded for first and second different computer architectures or coded to implement first and second different processing conventions. A memory stores instructions for execution by the processor pipeline, the memory being divided into pages for management by a virtual memory manager, a single address space of the memory having first and second pages. A memory unit fetches instructions from the memory for execution by the pipeline, and fetches stored indicator elements associated with respective memory pages of the single address space from which the instructions are to be fetched. Each indicator element is designed to store an indication of which of two different computer architectures and/or execution conventions under which instruction data of the associated page are to be executed by the processor pipeline. The memory unit and/or processor pipeline recognizes an execution flow from the first page, whose associated indicator element indicates the first architecture or execution convention, to the second page, whose associated indicator element indicates the first architecture or execution convention. In response to the recognizing, a processing mode of the processor pipeline or a storage content of the memory adapts to effect execution of instructions in the architecture and/or under the convention indicated by the indicator element corresponding to the instruction's page.
摘要:
A computer binary translator translates at least a segment of a binary representation of a program from a first instruction set architecture to a second instruction set architecture. A sequence of side-effects in the translation differs from a sequence of side-effects in the original. The translation distinguishes memory loads that are believed to be directed to well-behaved memory from memory loads that are believed to be directed to non-well-behaved memory device(s). Instruction execution circuitry identifies a memory reference that has a side-effect that has been reordered by translation, the memory reference having been believed at translation time to be directed to well-behaved memory but at execution it is found that the reference cannot be guaranteed to be well-behaved. The instruction execution circuitry identifies whether the difference in side-effect order may have a material effect on the execution of the program. A roll-back program state is established, and execution of the original code resumes.
摘要:
Profiling execution of a program. The program is coded in a mode-dependent instruction set. During a profile-quiescent execution interval, the profile circuitry records no profile information. After a triggering event is detected, the profile circuitry commences a profiled execution interval, and records profile information describing every profileable event during that interval. The profiled information includes at least all divergence of execution from sequential execution and processor mode changes not inferable from instruction opcode. The recorded profile information is efficiently tailored to annotate the profiled binary code with sufficient processor mode information to resolve mode-dependency, and indicates contiguous ranges of sequential instructions executed during a profiled interval by low and high boundaries of the contiguous ranges, indicating the high boundary by the address of the last byte. The profile information identifies each distinct physical page of instruction text executed during the interval.
摘要:
A method and a computer with circuitry configured for performance of the method are disclosed. During a profiled interval of an execution of a program on a computer, profile information is recorded describing the execution, without the program having been compiled for profiled execution. The program is coded in an instruction set in which an interpretation of an instruction depends on a processor mode not expressed in the binary representation of the instruction. The recorded profile information describes at least all events occurring during the profiled execution interval of the two classes: (1) a divergence of execution from sequential execution; and (2) a processor mode change that is not inferable from the opcode of the instruction that induces the processor mode change taken together with a processor mode before the mode change instruction. The profile information further identifies each distinct physical page of instruction text executed during the execution interval.
摘要:
A computer. An instruction pipeline and memory access unit execute instructions in a logical address space of a memory of the computer. An address translation circuit translates address references generated by the program from the program's logical address space to the computer's physical address space. Profile circuitry is cooperatively interconnected with the instruction pipeline and configured to detect, without compiler assistance for execution profiling, occurrence of profilable events occurring in the instruction pipeline, and is cooperatively interconnected with the memory access unit to record profile information describing physical memory addresses referenced during an execution interval of the program.
摘要:
A method and a computer for execution of the method. As part of executing a stream of instructions, a series of memory loads is issued from a computer CPU to a bus, some directed to well-behaved memory and some directed to non-well-behaved devices in I/O space. Computer addresses are stored of instructions of the stream that issued memory loads to the non-well-behaved memory, the storage form of the recording allowing determination of whether the memory load was to well-behaved memory or not-well-behaved memory without resolution of any memory address stored in the recording.
摘要:
A method and apparatus for improving the efficiency of executing arithmetic and logical operations performed on arguments provided during the execution of computer instructions in which operands include a variable type argument or data portion accompanied by a tag identifier which defines the data type. The processing of the data is enhanced by the addition of two condition codes derived from the values of the pre-ALU tag identifiers and the post-ALU results. The condition codes allow rapid determination of data types without additional execution cycles or hardware overhead, resulting in enhanced execution of the instructions.