JPH06242993A - Exception message generation system for information processor - Google Patents

Abstract

PURPOSE:To improve the performance by reducing the throughput of an exception processing means when an exception message for the exception is generated if an exception is generated during program execution. CONSTITUTION:An exception check means 1 once detecting the exception reports the ID number of the exception to the exception processing means 2. The exception processing means 2 retrieves a table 3 according to the ID number and reads out the contents of the corresponding entry. A flag indicating where exception information required for the message generation of the exception is present is previously set in the entry, so the exception information are taken out of places 4-7 by checking the flag to generate the exception message.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exception message generation system for an information processing apparatus, and in particular, information necessary for generating an exception message of an exception detected during program execution, according to the type of the exception. The present invention relates to an exception processing method in an information processing device configured to be taken out from each unit of the above.

[0002]

2. Description of the Related Art As a function of an information processing apparatus, it is constantly checked whether or not an instruction of software to be executed performs an illegal operation, and a specific event functionally incorporated occurs during execution of the instruction of software. It has a function to check whether or not they occur and to report them as exceptions to the software if they occur. Generally, this function is realized by activating exception handling means and performing exception handling when an exception is detected by hardware or firmware. The exception processing unit that has detected the exception creates an exception message for reporting to the software according to the functional specifications of the information processing device. This exception message is information including the type of exception and the element that caused the exception.

In order to create this exception message, there is a case where information that constitutes the exception message (referred to as exception information) is required. Conventionally, such information is provided by firmware or the like that operates at the time of exception check. After preparing, the method of checking the exception and the exception handling means after detecting the exception determine the kind of exception, analyze what is the exception information necessary for the exception message, where it is, etc. There is a method of collecting the information of and creating an exception message.

[0004]

In the former method of extracting the exception information described above, that is, in the method of preparing the information necessary for creating the exception message by the firmware or the like operating at the time of the exception check, the exception is generated. Since this method must be executed before the control is detected and the control is transferred to the exception processing means, a process of preparing exception information before the exception check is required. Therefore, the processing must be executed regardless of whether or not the exception is detected, and thus the normal processing of the firmware is affected,
There is a drawback in that performance is degraded.

In the latter of the conventional methods of extracting exception information, that is, in the method of analyzing where the exception information of the detected exception is, by the exception processing means,
It is necessary to perform individual processing for each type of exception, so there is a drawback that exception processing becomes complicated when the number of types of exception increases.

Therefore, the present invention has been made in order to solve the above-mentioned drawbacks of the conventional ones, and the purpose thereof is that the firmware operating at the time of exception check and the exception processing means prepare the exception information. It is an object of the present invention to provide an exception message generation system for an information processing apparatus, which eliminates the processing such as the above and simplifies the processing of the firmware and the exception processing means to improve the performance.

[0007]

An exception message generation system for an information processing apparatus according to the present invention is an exception check means for detecting exception occurrence during program execution and generating exception identification information for identifying the exception. And a table having entries respectively corresponding to all exceptions that may occur during the execution of the program, each entry having a flag pre-stored with a flag indicating a location for extracting exception information of the corresponding exception, Exception processing means for indexing the table using the exception identification information generated by the exception checking means as a key, referring to the flag of the indexed entry, deriving the exception information from the position indicated by this flag, and generating an exception message. It is characterized by including.

[0008]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a system block diagram of an embodiment of the present invention, and FIG. 2 is a diagram for explaining the entry contents of the exception table 3 shown in FIG. Referring to these two figures,
The exception checking means 1 always checks by hardware or firmware whether or not an exception has occurred during the sequential execution of software programs. The exception checking method is well known, and the well known method is Used.

In the exception check of the exception check means 1, exception identification information (ID number) for identifying and identifying each exception is given in advance so that exception processing can be performed easily. is there. For example, one exception is A,
Another exception is B, and yet another exception is C. For all possible exceptions, A, B, and
The ID numbers of C, ..., Z are given in advance.
When the exception checking means 1 detects an exception occurrence, it generates an ID number for identifying this occurrence.

When the exception processing means 2 receives the exception ID number from the exception checking means 1, the exception table 3 is searched by this ID number, the corresponding entry contents of this table 3 are read, and it is necessary to create an exception message. Collect exceptional exception information.

The exception table 3 has entries corresponding to all possible exceptions, and this entry can be searched using the ID numbers A, B, C, ..., Z of each exception as keys. Has become. The contents of this one entry 31 are shown in FIG.

As shown in FIG. 2, the entry 31 is composed of flags F1 to Fn indicating the location of the exception information and other information I necessary for exception processing and the like. Since the other information I is irrelevant to the present invention, its explanation is omitted. When the flag F1 is set to "1", it indicates that the exception information exists in the register 4, and when the flag F2 is set to "1", it indicates that the exception information exists in the memory 5. If the flag F3 is set to "1", it indicates that the exception information exists in the register 6.

Therefore, since the location of the exception information required for the exception message for each exception is known in advance when the program is created, the relevant flag (single or single) among the flags F1 to Fn of each entry in the table 3 is determined. By setting "1" in a plurality of flags), it is assumed to be registered in advance.

The operation of such a structure will be described. It is assumed that the exception checking means 1 detects that an exception with the ID number C has occurred while executing a certain instruction of a certain program. In response to this detection, the exception checking means 1 reports the fact to the exception processing means 2 and also generates the ID number of the exception and sends it to the exception processing means 2.

Upon receipt of this report, the exception processing means 2 takes over the control operation of the information processing apparatus, searches the entry of the table 3 using the ID number sent from the exception checking means 2, and reads the contents of the entry C. put out. This entry C
In the table, the extraction flags F1 to Fn of the exception information necessary to create the exception check of the ID number C are stored together with other information I.

Therefore, the exception processing means 3 searches for a flag in which "1" is set among the exception information fetch flags F1 to Fn, reads out the necessary exception information from the portion indicated by the set flag, The exception message is created.

For example, if the flag set in the entry C is only F1, it is known that the necessary exception information exists in the register 4 indicated by this flag F1, so the contents of the register 4 are read out and the The exception information will be generated using the read information.

If there are a plurality of flags set, it means that the information necessary for creating the exception message exists in two or more places. Therefore, the exception information is read from the place indicated by each flag and the exception message is read. Will be used to create.

In addition, even if the exceptions are of the same type, the required information may exist in different places depending on the situation. In this case, different ID numbers are given to the same type of exceptions, and the exception information take-out flag is set separately, so that necessary information can be obtained for each.

[0021]

As described above, according to the present invention, when an exception message for an exception detected by the exception checking means is created, it is preliminarily determined where in the information processing system the information necessary for the exception message exists. It is possible to register in the entry of the table, read the corresponding entry from the table in response to the occurrence of the exception, and collect the necessary information according to the contents of this entry.
There is no need for the processing that prepares the exception information necessary for the firmware that is operating during exception checking to create the exception message, and the processing that the exception processing means analyzes the exception and then retrieves the exception information. There is an effect that the processing of is simplified and the performance can be improved.

[Brief description of drawings]

FIG. 1 is a system block diagram of an embodiment of the present invention.

FIG. 2 is a diagram for explaining the contents of entries in the exception table of FIG.

[Explanation of symbols]

 1 Exception Checking Means 2 Exception Handling Means 3 Exception Table 31 Exception Table Entries F1 to Fn Flags

Claims (1)

[Claims] 1. Exception checking means for detecting the occurrence of an exception during execution of a program and generating exception identification information for identifying the exception, and corresponding to all exceptions that may occur during the execution of the program. Table in which each entry has a flag in which a flag indicating a location for extracting the exception information of the corresponding exception is stored in advance, and the table is indexed using the exception identification information generated by the exception checking means as a key. An exception message generating system for an information processing apparatus, comprising: an exception processing unit that refers to the flag of the indexed entry and derives exception information from the position indicated by the flag to generate an exception message.