JPH0452937A - System for avoiding impossibility of operation of execution form software - Google Patents

Abstract

PURPOSE:To use already prepared execution form software by providing an instruction substituting means, which substitutes the instruction causing an access boundary disaccord with an instruction by which access boundary disaccord error does not occur, and a re-executing means which re-executes the processing which the former instruction should execute. CONSTITUTION:An instruction position search means 1 searches the position of the instruction by which access boundary disaccord occurs, and an instruction classification analyzing means 2 analyzes the classification of this instruction. An instruction substituting means 3 substitutes this instruction with an instruction by which access boundary disaccord error does not occur, and a re- executing means 4 re-executes the processing which the former instruction should execute. Consequently, examination and rewrite due to recompilation of the source code of already prepared execution-form software or the change of the source code are unnecessary through access boundary adjustment is handled differently among hardware, architecture, and a used compile language. Thus, the already prepared execution-form software can be used.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for avoiding executable software inoperability, and in particular to software porting between computers with different computer hardware, architecture, and access boundary adjustment of compiled languages used. This invention relates to a method for avoiding execution of executable software.

[Conventional technology]

Conventionally, when porting existing executable software, if the handling of access boundary adjustment differs between the hardware, architecture, and compiled language used, the software source code must be recompiled or the source code table (IF!4 structure) ), etc., the instructions used, and the processing method, and the only way to do this was to rewrite the source code so that the access boundaries matched.

[Problem to be solved by the invention]

With conventional software porting, when the hardware, architecture, and compiled language used require access boundary adjustment, or when the memory layout is handled differently, when the executable software is run as is, it may not work properly due to incorrect boundaries. There's a problem. To avoid this, either recompile the source code of the executable software, or review the source code and investigate the memory layout of tables (structures) in the source code and the instruction processing method used. The disadvantage is that the source code must be rewritten to match the boundaries.

[Means to solve the problem]

The executable software inoperability avoidance method of the present invention includes an instruction location search means for searching the position (address) of an instruction that causes an access boundary mismatch, and an instruction type analysis means that analyzes the type of instruction that causes an access boundary mismatch. , an instruction replacement means for replacing an instruction that causes an access boundary mismatch with an instruction that does not cause an access boundary mismatch error, and a re-execution means that re-executes the process that the instruction that caused the access boundary mismatch attempts to execute. Ru.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Fig. 1 is a flowchart showing the configuration of an embodiment of the present invention, Fig. 2 is a block diagram showing an overview of the operation of this embodiment, and Fig. 3 is a case where an access boundary mismatch error occurs regarding the operation of this embodiment. It is an explanatory view showing a concrete example of avoidance.

In FIG. 2, when the program 12 running on the O8 generates a program interrupt due to an access boundary mismatch, countermeasure processing is performed by the program interrupt processing means 13 of the O8.

Furthermore, in the case of a program interrupt other than an access boundary mismatch error, it is handled by the processing means 14 for other program errors, and it is determined whether or not to return to the point at which the program interrupt occurred. In the case of a program interrupt due to an access boundary mismatch error, it is determined whether or not to be handled by the executable software inoperability avoidance means 15 when the access boundaries are different, and to return when the program interrupt occurs.

A more specific explanation will be given with reference to FIG. 1 and FIGS. 3(a) and (b).

As shown in FIG. 3(a), when the access boundary is a transfer command (load, store, move, etc.) that requires a 4-byte boundary, in the case of the access boundary mismatch avoidance example shown in FIG. 3(a), In FIG. 1, a program error due to access boundary mismatch is detected, and the instruction position search means 1 searches for the location (address) of the instruction causing the access boundary mismatch, and approaches the point in time when a program interrupt occurs.

Then, the instruction type analysis means 2 that analyzes the type of instruction that caused the access boundary mismatch determines whether the instruction is to avoid the access boundary mismatch. In this example, the transfer instruction (
load, store, move, etc.), the instruction replacement means 13 replaces the instruction that causes an access boundary mismatch with an instruction that does not cause an access boundary mismatch error. ). The re-execution means 14 re-executes the process attempted by the instruction that caused the access boundary mismatch, so that data can be correctly stored or retrieved in an area with a different access boundary.

As shown in FIG. 3(b), when the boundary is a 4-byte boundary (conveyor, etc.),
) In the case of the boundary mismatch avoidance example shown in Figure 1, it is detected as an access boundary mismatch program error,
The instruction replacement search means 1 searches for the location (address) of the instruction that caused the access boundary mismatch, and the program interrupt generation point is approached.

Then, the instruction type analysis means 2, which analyzes the type of instruction that caused the access boundary mismatch, determines whether there is an instruction that avoids the access boundary mismatch.

In this example, since it is a judgment instruction (conveyor, etc.) that requires avoiding access boundary mismatch, the data is changed to The data to be determined is moved byte by byte to a separately provided work area on a 4-byte boundary using an instruction to transfer byte by byte (which does not cause an access boundary mismatch error). Data in areas with different access boundaries can be correctly determined by the re-execution means 14, which re-executes the process that the instruction that caused the access boundary mismatch attempts to execute.

As described above, this embodiment avoids access boundary mismatch when transferring or determining data.

〔Effect of the invention〕

As explained above, in porting existing executable software, the present invention enables recompilation of the source code of the existing executable software and course code even if the handling of access boundary adjustment is different between the hardware, architecture, and compiled language used. investigation by reviewing the
This has the advantage that existing executable software can be used without rewriting it.

FIG. 4 is an explanatory diagram showing a specific avoidance example when

1... Instruction position search means, 2... Instruction type analysis means, 3... Instruction replacement means, 4...
...Means for re-execution.

Claims (1)

[Claims] Location (address) of the instruction that caused the access boundary mismatch
an instruction position search means for searching for an access boundary mismatch, an instruction type analysis means for analyzing the type of instruction that caused an access boundary mismatch, and an instruction replacement means for replacing the instruction that caused an access boundary mismatch with an instruction that does not cause an access boundary mismatch error; 1. An executable software operation avoidance method characterized by comprising: re-execution means for re-executing a process attempted to be executed by an instruction that caused an access boundary mismatch.