JPH02138631A - Information saving/restoring system - Google Patents

Abstract

PURPOSE:To minimize the number of registers to be saved and restored when an interruption is occurred by making use of such characteristics where the information stored in other registers can be maintained with no change caused before and after an information process when an information process system carries out an optional information process. CONSTITUTION:When an interruption is occurred, a saving/restoring means 200 refers to a subject register display means 100 to save the information stored in a register shown by the corresponding subject register information rs into the corresponding saving area as. Then the means 200 refers again to the means 100 when the process is through with the interruption and restores the information saved in the area as shown by the information rs to the corresponding register. Thus it is possible to save and restore the least necessary registers at occurrence of an interruption. Then the saving/restoring time can be shortened.

Description

[Detailed Description of the Invention] [Summary] Regarding the improvement of an information saving/restoring method in an information processing system equipped with an interrupt processing function, it is possible to allocate memory storage areas without reducing the information processing ability of the information processing system. The purpose is to make it possible to save and restore information at the time of an interrupt without imposing any restrictions on the interrupt.
target register display means for holding save target register information indicating the type of register to save accumulated information and a save area indicating a save destination of the accumulated information; and when an interrupt occurs, refer to the target register display means; When the information accumulated in the register indicated by the corresponding save target register information is saved to the corresponding save area and the processing related to the generated interrupt is completed, refer to the target register display means,
A saving/restoring means is provided for restoring the information being saved in the saving area indicated by the corresponding saving target register information to the corresponding register.

[Industrial application field]

The present invention relates to an improvement in an information saving and restoring method in an information processing system equipped with an interrupt processing function.

While an information processing system equipped with an interrupt processing function is executing information processing, if an interrupt occurs from an input/output device that was operating in parallel due to reasons such as indicating that an operation has been completed, After interrupting information processing and executing processing related to the interrupt that occurred, in order to resume the interrupted information processing, temporarily save the various information that was used for information processing at the time of interruption, and save the various information that was saved when restarting. needs to be restored.

[Conventional technology]

FIG. 5 is a diagram showing an example of a conventional information processing system.

In FIG. 5, 1 is a processor having an interrupt processing function, 111 to 11n are n registers that store various information used by the processor 1 for information processing, and 2-1 and 2-2 are memories.

Interrupted program pi stored in memory 2-1 by processor 1. While information processing is being executed by
When an interrupt occurs that requests execution of information processing by the interrupt programs P and 7 stored in processor 1, processor 1
is the interrupted program P. By temporarily suspending the information processing by the program Psr and executing the save process by the save/restore program Psr stored in the memory 2-2, the data stored in all the registers 121 to 11n at the time of the stop will be saved. , to dfi to the save areas a to a0 provided in the memory 2-1 corresponding to the registers 111 to 11n, and then by the interrupt program p in stored in the memory 2-1. Start executing information processing.

When the information processing by the interrupt program p in is completed,
By executing the restoration process by the evacuation/restoration program P stored in the memory 2-2, the processor l saves all the data d1 to d7 that had been saved to the evacuation areas aS+ to asll in the memory 2-1. register 111 of
After accumulating in 11n to 11n, the interrupted program P,. resumes information processing from the point of interruption.

[Problem to be solved by the invention]

As is clear from the above explanation, in a conventional information processing system, when an interrupt occurs, data is stored in all registers 111 to 11n by executing a save process using the save/restore program psr. By unconditionally saving the data d to dh and executing the restoration process by the save/restore program Psr when the information processing related to the interrupt is completed, all the data d to d7 that have been saved are saved. As the number of registers n included in the processor 1 increases, the time required for saving and restoring processing increases, especially for information processing systems that target real-time processing. There were problems that reduced performance.

In order to solve this problem, registers 111 to 11
Providing a dedicated circuit for saving and restoring the data d to d7 accumulated by n is considered, but as the number of registers n increases, the operating time also increases, and saving and restoring by the save and restore program Psr is also considered. As in processing, it becomes difficult to freely allocate the save areas as+ to ash,
There is a problem in that restrictions increase in the allocation of storage areas of the memories 2-1 and 2-2.

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to save and restore information in the event of an interrupt without reducing the information processing capacity of an information processing system and without imposing restrictions on the allocation of memory storage areas.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the present invention.

In FIG. 1, it is assumed that the information processing system is equipped with an interrupt processing function.

100 is a target register display means provided in the information processing system according to the present invention.

Reference numeral 200 denotes a save/restore means provided in the information processing system according to the present invention.

[Effect]

When an information processing system executes arbitrary information processing, it does not necessarily use all the registers included in the information processing system, but it often uses some registers. Therefore, the information stored in other registers is maintained unchanged before and after the information processing.

The present invention is intended to utilize such characteristics to reduce as much as possible the number of registers to be saved and restored when an interrupt occurs.

The target register display means 100 displays save target register information rs indicating the type of register to save accumulated information and save target register information rs indicating the save destination of the accumulated information, corresponding to the interrupt factor number I indicating the type of interrupt that occurs. Hold area a5.

When an interrupt occurs, the save/restore means 200 refers to the target register display means 100 and saves the information accumulated in the register indicated by the corresponding save target register information rs to the corresponding save area a. When the processing related to the generated interrupt is completed, the target register display means 10
0, the information being saved in the save area a indicated by the corresponding save target register information r is restored to the corresponding register.

Therefore, when an interrupt occurs, only the minimum necessary registers can be saved and restored, reducing the time required for saving and restoring, and increasing the information processing capacity of the information processing system for real-time processing. It is possible to prevent a decrease in the storage area, and the save area can also be set freely, making it possible to allocate the storage area of the memory with flexibility.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram showing an information processing system according to an embodiment of the present invention, FIG. 3 is a diagram illustrating the register information to be saved in FIG. 2, and FIG. FIG. 4(a) is a diagram illustrating an operation, and FIG. 4(a) indicates a retracting operation, and FIG.

In FIG. 2, an interrupt control table T is provided in the memory 2-3 as the target register display means 100 in FIG.
A save/restore circuit 12 is provided which executes a save operation as shown in FIG. 4(a) and a restore operation as shown in FIG. 4(b).

The interrupt control tables T are provided corresponding to the interrupt cause numbers ■ indicating the types of interrupts that occur, and each interrupt control table T includes information about the interrupts that the processor 1 has assigned the interrupt cause numbers I. The processor 1 assigns the storage address ain of the interrupt program P in for executing processing and the interrupt cause number ■ by the interrupt program P, 1 among the registers 111 to 11H provided in the information processing system. A save indicating the type of register llx that needs to save the data dX (where X is any one from 1 to n) that was accumulated at the time the interrupt occurred, in order to be used when executing the interrupted interrupt processing. It holds target register information r, and save areas a and x indicating the save destination of data dx accumulated by the register 1x.

As shown in FIG. 3, the save target register information r3 has bits tz to bn corresponding to the registers 111 to 11n provided in the information processing system, respectively, and is used during interrupt processing due to interrupt factor number I. The bit bX corresponding to the register llx that is saved and needs to be saved is set to logic "1", and the bit bX that is not used during interrupt processing and does not need to be saved is set to the register 11y (however, y is any one of 1 to n). So, y≠X
) is set to logic "0".

In FIGS. 2 to 4, a processor 1 is connected to a memory 2-
The interrupted program P, stored in . When an interrupt occurs that requests execution of information processing by the interrupt program pia stored in the memory 2-1 while executing information processing by the interrupt program P, the processor l executes the interrupted program P,
. After temporarily suspending the information processing by
and transmits the interrupt factor number I and save request signal Sq (FIG. 4 (as step 5ll)).

The save/restore circuit 12 that has received the save request signal SQ refers to the interrupt control table T corresponding to the interrupt factor number I transmitted from the processor l, and extracts the save target register information r8 and the save area alk ( Step 512).

Next, the save/restore circuit 12 analyzes the extracted save target register information r, and identifies the register 11 to be saved from the bit bx set to logic "l", and stores the information r in the register llx. The data dX is saved to the save area asx (step 513).

When the saving of data d from the register Ilx to the save area asx is completed, the saving/restoring circuit 12 returns a saving completion signal S to the processor 1 (step 514).
.

The processor 1 that received the evacuation completion signal S1 stores the memory 2
Refer to the interrupt control table T corresponding to the interrupt factor number ■ stored in -3, and find the storage address ain of the interrupt program Pifi for executing the interrupt process assigned the interrupt factor number I. After the extraction, information processing by the interrupt program p in stored in the memory 2-1 is performed in the register Il.
Start execution using x.

When the information processing by the interrupt programs P and 7 is completed, the processor l activates the save/restore circuit 12 and transmits the interrupt cause number ■ and the restore request signal rQ (see FIG.
Step 521).

The save/restore circuit 12 that has received the restore request signal r9 refers to the interrupt control table T corresponding to the interrupt cause number I transmitted from the processor 1, and extracts the register information r1 to be saved and the save area a*X. (step 322).

Next, the save/restore circuit 12 analyzes the extracted save target register information rj and identifies the register 11x to be restored from the bit bX set to logic "1".
Evacuation area a. The data dX saved in is stored in the register ttx (step 523).

Evacuation area a. When the restoration of data d from to register llx is completed, the save/restore circuit 12 returns a restoration completion signal r to the processor 1 (step 524).

The processor 1 that has received the restoration completion signal r1 executes the interrupted program P,. resumes information processing from the point of interruption.

As is clear from the above description, according to the present embodiment, the save/restore circuit 12 saves/restores only the data dX stored in the register llx used for information processing by the interrupt program pin. The time required for saving and restoring is reduced regardless of the number n of registers included in the information processing system.

In addition, the data d8 save area as)I is preliminarily set to the interrupt control table T.
It is only necessary to set it to , and it is possible to assign it arbitrarily.

Note that FIGS. 2 to 4 are only one embodiment of the present invention, and for example, the target register display means 100 is not limited to the illustrated interrupt control table T, and may be modified in many other ways. However, the effects of the present invention remain the same in either case. Further, the saving/restoring means 200 is not limited to the saving/restoring circuit 12 shown in the figure, and many other modifications may be considered, but the effects of the present invention remain the same in any case. Furthermore, it goes without saying that the configuration of the information processing system to which the present invention is applied is not limited to that shown in the drawings.

〔Effect of the invention〕

As described above, according to the present invention, when an interrupt occurs in the information processing system, only the minimum necessary registers can be saved and restored, so the time required for saving and restoring is shortened, and the real time It becomes possible to prevent a decline in the information processing capacity of the information processing system targeted for processing, and it is also possible to freely set the save area, making it possible to flexibly allocate the storage area of the memory.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the principle of the present invention, FIG. 2 is a diagram showing an information processing system according to an embodiment of the present invention, FIG. 3 is a diagram illustrating the register information to be saved in FIG. 2, and FIG. is a diagram illustrating the evacuation/restoration operation in FIG. 2, FIG. 4(a) shows the evacuation operation, FIG. 4(b) shows the restoring operation,
FIG. 5 is a diagram showing an example of a conventional information processing system. In the figure, ■ is a processor, 2-1 to 2-3 are memories, 12 is a save/restore circuit, 100 is a target register display means, and 111 to 11n are registers. Tehe No. 2 The wooden tomb and the door of the sun and the moon. 5. 1. 2 rfn + = Okero υ request, Resonu 2 go appetizers to the alliance Menjo no Morizu. 3 mouth iLsu Akane Hiromo I 1000 restoration work. Shimoyu E2Gro (: 1bu iggi!・I return no i'Kamashihii T broom 4 6

Claims (1)

[Scope of Claims] In an information processing system equipped with an interrupt processing function, a save target indicating the type of register to save accumulated information in correspondence to an interrupt cause number (I) indicating the type of interrupt that occurs. Target register display means (100) that holds register information (r_s) and a save area (a_s) indicating a save destination of the accumulated information, and when an interrupt occurs, refer to the target register display means (100), The target register display means (100) saves the information accumulated in the register indicated by the corresponding save target register information (r_s) to the corresponding save area (a_s), and when the processing related to the generated interrupt is completed. and a saving/restoring means (200) for restoring information being saved in the saving area (a_s) indicated by the corresponding saving target register information (r_s) to the corresponding register. Information backup and restoration method.