A data processing system handles memory management exceptions caused by a faulting vector instruction in a vector processor by halting the execution of the faulting vector instruction being executed when the exception occurred and by setting the state information for the vector processor to acknowledge the presence of the exception and to include information about the suboperation of the vector instruction being executed when the exception occurred. The scalar processor is not interrupted at this time, however. Any other vector instructions executing simutaneously with the faulting vector instruction are allowed to continue so long as those instructions do not require data from the faulting instruction. The faulting partially completed vector instruction resumes execution after the operating system has processed the memory management exception.
A digital computer system comprises a precise exception handling processor and a control subsystem. The precise exception handling processor performs processing operations under control of instructions. The precise exception handling processor is constructed in accordance with a precise exception handling model, in which, if an exception condition is detected in connection with an instruction, the exception condition is processed in connection with the instruction. The precise exception handling processor further includes a pending exception indicator having a pending exception indication state and a no pending exception indication state. The control subsystem provides a series of instructions to the precise exception handling processor to facilitate emulation of at least one emulated program instruction. The emulated program instruction is constructed to be processed by a delayed exception handling processor which is constructed in accordance with a delayed exception handling model, in which if an exception is detected during processing of an instruction, the exception condition is processed in connection with a subsequent instruction. The series of instructions provided by the control subsystem in emulation of the emulated program instruction controls the precise exception handling processor to (i) determine whether the pending exception indicator is in the pending exception indication state and, if so, to invoke a routine to process the pending exception and condition the pending exception indicator to the no pending exception indication state (ii) perform processing operations in accordance with the emulated processing instruction; and (iii) if an exception condition is detected during the processing operations, to invoke an exception handler in accordance with the processor's precise exception handling model to condition the pending exception indicator to the pending exception indication state, so that the exception condition will be processed during processing operations for a subsequent emulated program instruction.
An arithmetic processing method and arithmetic processing device each which can reduce the number of logical stages needed to obtain the final arithmetic result, thus executing an arithmetic process such as a floating-point multiplication at high speed to reduce the arithmetic process time. According to the arithmetic processing method and arithmetic processing device, the possibility that an arithmetic exception occurs in the arithmetic result obtained through an arithmetic process is judged in the middle of the arithmetic process of the dedicated arithmetic processing unit. Transmitting an arithmetic end signal to the instruction control unit is inhibited when it is judged that there is a possibility; the arithmetic process with the possibility is executed by means of another arithmetic unit different from the dedicated arithmetic unit. Thereafter the arithmetic end signal regarding the arithmetic process is transmitted to the instruction control unit. The arithmetic processing method and arithmetic processing device can be applied to the case where an arithmetic process such as a floating-point arithmetic operation is performed in a pipeline mode.
A troubleshooting apparatus, troubleshooting method and recording medium recorded with troubleshooting program, by which a cause of occurrence of exception occurred in a network computing environment can be promptly diagnosed, by bundlingly collecting the occurrence informations concerning the exceptions when the exception occurrence in the application program is detected.
A method, system and processor are provided for minimizing latency and loss of processor bandwidth in a pipelined processor when responding to an interrupt. The method advantageously avoids emptying and refilling the processor's instruction pipeline in order to service an interrupt request. Instead, a short sequence of instructions comprising the interrupt response is inserted into the pipeline. Normal pipeline operation stalls while the inserted instructions execute, but since flow is not disrupted the loss in bandwidth is not as great as if the pipeline were flushed. Furthermore, direct insertion of the instructions into the pipeline avoids the need for the processor to save its context and branch to an interrupt service routine in memory; this results in much faster response in servicing the interrupt, thereby reducing latency. In the preferred embodiment, the method applies to a pipelined processor having a RISC (Reduced Instruction Set Computer) architecture, which receives interrupt requests from one or more DMA memory controllers. The instructions inserted into the pipeline compute block address information for a DMA transfer. A system and processor implementing the method are disclosed, based on an enhancement of a conventional RISC processor design, and making use of registers and other existing logic resources within the processor. It is shown that the enhanced processor can respond to DMA interrupts with shorter latency and a smaller reduction in processor bandwidth than if conventional interrupt handling were used.
In a communication system wherein a collecting communication unit of a plurality of communication units collects state information from report communication units to manage the state information, each of the report communication units comprises a state information memory for storing the state information of own communication unit, a state monitoring portion for monitoring the state information of own communication unit and then rewriting the stored state information into new state information after change if the state information has been changed, and a transmitting/receiving portion for adding the stored state information and own address to the recovery command and then transmitting the recovery command when respective report communication units receive the recovery command for recovering the state information, whereby the collecting communication unit can receive the recovery command to which changed state information and their own addresses of respective report communication units are added collectively.
