JP2010282441A - Apparatus for calculating inter-module dependent strength, method and program for measuring inter-module dependent strength - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for calculating inter-module dependent strength and a method and a program for measuring inter-module dependent strength which quantitatively evaluate dependent strength between modules even in software prepared by a language whose class is not supported and which have high versatility. <P>SOLUTION: In the apparatus 10 for calculating inter-module dependent strength, a source code acquisition part 11 obtains source codes by a module unit. A global variable extraction part 12 extracts global variables included in source codes of at least a part of modules. An access frequency counting part 13 finds out access frequencies for at least a part of global variables for each global variable. A dependent strength calculation part calculates dependent strength between a plurality of modules for each global variable based on the access frequency. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an inter-module dependency strength calculation apparatus, an inter-module dependency strength measurement method, and an inter-module dependency strength measurement program that quantitatively evaluate the degree of influence of a plurality of modules included in software.

  In software development, a software unit having a group for each function is generally called a module. By developing software for each module, development and testing can be performed in parallel for each module, and efficient software development can be performed. Further, by providing a module with a predetermined function as one component of software and developing a module having versatility, the same module can be widely used in a plurality of different software.

  However, there is a problem in that the more software is divided into modules, the more complicated the dependency relationship between the modules and the lowering of software maintainability. Therefore, it is desirable to quantitatively evaluate and grasp the dependency relationship between modules in order to suppress an increase in the possibility of a decrease in software maintainability due to excessively complicated dependency relationship between modules.

  As an inter-module dependency strength calculation device according to the prior art, a dependency measurement device between software modules having an all-class total combination deriving unit for extracting a class of software and deriving the combination, and an analysis unit and an analysis value storage unit Is known. This dependency measurement device between software modules measures the dependency on the data of an object belonging to a certain class, the input / output to / from the object, and the dependency on the operation in the object (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2000-215045

  Since the inter-module dependency strength calculation apparatus according to the prior art uses an object-oriented concept called class, only object-oriented programming languages such as C ++ and Java (registered trademark), that is, programming languages that support classes are applied. There is a problem that it is not possible.

  An object of the present invention is to provide a highly versatile inter-module dependency strength calculation apparatus and inter-module dependency that can quantitatively evaluate the dependency strength between modules even for software created in a programming language that does not support classes. An intensity measurement method and an inter-module dependent intensity measurement program are provided.

The present invention includes a source code acquisition unit that acquires source code in module units,
A global variable extraction unit that extracts global variables included in the source code of at least some of the modules acquired by the source code acquisition unit;
Access for measuring, for each global variable, the number of accesses to the global variable in a plurality of modules among the at least some of the global variables extracted by the global variable extraction unit. Counting unit,
A dependency strength calculating unit that calculates a dependency strength between the plurality of modules whose access count is measured by the access count measuring unit for each global variable based on the access count. It is a calculation device.

Further, according to the present invention, the access count measuring unit includes the number of writes to the global variable in one module, the number of reads to the global variable in the remaining modules, among the plurality of modules to be measured for the number of accesses. As the number of accesses,
The dependency strength calculation unit sets the dependency strength of the remaining modules for the one module via the global variable to the number of writes to the global variable in the one module and the number of reads to the global variable in the remaining module. It is calculated based on.

  Further, according to the present invention, the dependency strength calculation unit is configured to determine the dependency strength of a remaining module for one module among the plurality of modules, the number of times of writing to the global variable in the one module, and the remaining module. It is calculated as the product of the number of reads for the global variable in

According to the present invention, the access count measuring unit is configured to perform the above-described processing on all the global variables included in the source code of two modules among the at least some modules from which the global variables are extracted by the global variable extracting unit. The number of accesses to the global variable in one module is measured for each global variable,
The dependence strength calculating unit is a total dependence strength of the other module with respect to one of the two modules,
It is characterized in that a total dependency strength obtained by summing the dependency strength of the other module with respect to one module with respect to all global variables included in the source code of these two modules is calculated.

Further, the present invention uses the inter-module dependence strength calculation device,
A source code obtaining step of obtaining source code in module units by the source code obtaining unit;
Of the modules acquired in the source code acquisition step, a global variable extraction step of extracting global variables included in the source code of at least some modules by the global variable extraction unit;
Of the global variables extracted in the global variable extraction step, for at least some of the global variables, the number of accesses to the global variables in a plurality of modules of the at least some of the modules is determined by the access count measurement unit. Access count measurement process to measure for each variable,
A dependency strength calculation step of calculating, for each global variable, the dependency strength between the plurality of modules whose access count has been measured in the access count measurement step based on the access count by the dependency strength calculation unit. The inter-module dependence strength calculation method.

The present invention also provides a computer,
Source code acquisition unit that acquires source code in module units,
A global variable extraction unit that extracts global variables included in the source code of at least some of the modules acquired by the source code acquisition unit;
Access for measuring, for each global variable, the number of accesses to the global variable in a plurality of modules among the at least some of the global variables extracted by the global variable extraction unit. A frequency measurement unit, and a dependency strength calculation unit that calculates the dependence strength between the plurality of modules whose access count is measured by the access count measurement unit for each global variable based on the access count. This is an inter-module dependence strength calculation program.

  According to the present invention, the access count measurement unit obtains the access count for each global variable for at least some of the global variables extracted by the global variable extraction unit. The number of accesses is the number of accesses to a global variable in a plurality of modules. The dependency strength calculation unit calculates the dependency strength between the plurality of modules for each global variable based on the number of accesses. As a result, even when a plurality of types of global variables are used in the module source code, and the plurality of modules are related via a plurality of global variables, the dependency strength between the plurality of modules can be calculated. . Therefore, the dependency strength between modules can be quantitatively evaluated even for software created in a non-object-oriented programming language that does not support classes. As a result, a highly versatile inter-module dependence strength calculating device can be realized. This also makes it possible to find a module in which the dependency relationship between modules is complicated when developing software including source code in module units. Therefore, it is possible to suppress the possibility of a decrease in software maintainability in software development due to the complicated dependency between modules.

  According to the invention, the dependency strength calculation unit calculates the dependency strength of the remaining modules for one module via the global variable. This dependency strength is calculated based on the number of writes to the global variable in the one module and the number of reads to the global variable in the remaining modules. As a result, the dependency strength of the remaining modules with respect to one module among the plurality of modules can be calculated with respect to the global variable. Therefore, the magnitude of the influence between the plurality of modules can be quantitatively evaluated by distinguishing the module on the influence side from the module on the influence side via the global variable.

  Further, according to the present invention, the dependency strength calculation unit calculates a dependency strength related to a global variable of a remaining module with respect to one module among the plurality of modules for which the number of accesses is measured, as a global variable in the one module. Is calculated as the product of the number of writes to and the number of reads for the global variables in the remaining modules. Thereby, the influence between modules can be evaluated quantitatively according to the number of times of writing and the number of times of reading. A module that writes to a global variable affects other modules that read the global variable, and the degree of influence increases as the number of writes and the number of reads increase. Therefore, the influence of the remaining modules on one module can be quantitatively evaluated according to the number of times of writing and the number of times of reading.

  According to the present invention, the access count measuring unit measures the access count for the global variables in the two modules for each global variable for all global variables included in the source code of the two modules. The dependency strength calculation unit calculates the total dependency strength of the other module with respect to one of the two modules. The total dependency strength is obtained by summing the dependency strength of the other module with respect to one module with respect to all global variables included in the source code of these two modules. Thus, the influence of one module and the other module can be comprehensively evaluated with respect to all global variables included in the source code of these two modules. As a result, when developing software including source code in units of modules, it is possible to find a module having a complicated dependency relationship between modules. Therefore, in software development, the possibility of software maintainability degradation can be suppressed.

  According to the present invention, in the access count measuring step, the access count is measured for each global variable by the access count measuring section for at least some of the global variables. In the dependency strength calculation step, the dependency strength between the plurality of modules is calculated for each global variable based on the number of accesses by the dependency strength calculation unit. As a result, even when a plurality of types of global variables are used in the module source code and the plurality of modules are related via the plurality of global variables, the dependency strength between the plurality of modules can be calculated. . Therefore, the dependency strength between modules can be quantitatively evaluated even for software created in a non-object-oriented programming language that does not support classes. As a result, a highly versatile inter-module dependence strength calculating device can be realized. This also makes it possible to find a module in which the dependency relationship between modules is complicated when developing software including source code in module units. Therefore, it is possible to suppress the possibility of a decrease in software maintainability in software development due to the complicated dependency between modules.

  According to the present invention, the inter-module dependency strength calculation program causes a computer to function as a source code acquisition unit, a global variable extraction unit, an access count measurement unit, and a dependency strength calculation unit. As a result, the computer can function as an inter-module dependence strength calculation device.

It is a block diagram showing the structure of the inter-module dependence intensity | strength calculation apparatus 10 which concerns on 1st Embodiment of this invention. It is a flowchart showing each process of the inter-module dependence intensity | strength calculation method which concerns on 1st Embodiment of this invention. It is a figure showing an example of the source code acquired by the source code acquisition part 11 in 1st Embodiment of this invention. It is a flowchart showing each stage of the global variable extraction process in 1st Embodiment of this invention. It is a flowchart showing each step | level of the access frequency measurement process in 1st Embodiment of this invention. It is a figure showing the mode of access in each module of each global variable in 1st Embodiment of this invention. It is a flowchart showing each step of the dependence intensity | strength calculation process in 1st Embodiment of this invention.

  Hereinafter, a plurality of embodiments for carrying out the present invention will be described with reference to the drawings. In the following description, parts corresponding to items already described in the forms preceding each form may be denoted by the same reference numerals, and overlapping descriptions may be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding section. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder. Moreover, each embodiment is illustrated in order to embody the technique which concerns on this invention, and does not limit the technical scope of this invention. The technical contents according to the present invention can be variously modified within the technical scope described in the claims. The following description also includes descriptions of the inter-module dependence strength calculation device 10, the inter-module dependence strength measurement method, and the inter-module dependence strength measurement program.

(First embodiment)
FIG. 1 is a block diagram showing a configuration of an inter-module dependence strength calculation apparatus 10 according to the first embodiment of the present invention. The inter-module dependence strength calculation device 10 is a device that quantitatively evaluates the degree of influence of a plurality of modules included in software on each other. In the first embodiment, the inter-module dependency strength calculation device 10 includes a source code acquisition unit 11, a global variable extraction unit 12, an access count measurement unit 13, and a dependency strength calculation unit 14. The source code acquisition unit 11 acquires source code in module units.

  The global variable extraction unit 12 extracts global variables included in the source code 15 of at least some of the modules acquired by the source code acquisition unit 11. A global variable is a variable accessed in a plurality of different modules. Access includes writing to and reading from a global variable within the source code 15 included in the module, and the access count includes the write count and the read count.

  The access count measurement unit 13 obtains the access count for each global variable for at least some of the global variables extracted by the global variable extraction unit 12. The number of accesses is the number of accesses to a global variable in a plurality of modules. The plurality of modules are a plurality of modules among the modules that are global variable extraction targets by the global variable extraction unit 12. The dependency strength calculation unit 14 calculates the dependency strength 19 between the plurality of modules for each global variable based on the number of accesses.

  In the first embodiment, the dependency strength 19 is obtained when one source code 15 and another source code 15 included in a plurality of different modules via a global variable are related to each other. 15 represents the depth of the relationship. Since the source code 15 is handled in units of modules, the source code 15 having a unit as a module may be simply referred to as a “module”.

  The access count measurement unit 13 measures, as the access count, the number of writes to the global variable in one module and the number of reads to the global variable in the remaining modules among the plurality of modules for which the access count is to be measured. The dependency strength calculation unit 14 calculates a dependency strength 19 of the remaining modules for the one module via a global variable. The dependency strength 19 is calculated based on the number of writes for the global variable in the one module and the number of reads for the global variable in the remaining modules.

  The dependency strength calculation unit 14 sets the dependency strength 19 related to the global variable of the remaining modules for one module among the plurality of modules to be subjected to the access count measurement, the number of writes to the global variable in the one module, Calculated as the product of the number of reads for global variables in the remaining modules.

  In the present embodiment, the inter-module dependency strength calculation apparatus 10 is realized by a computer and an inter-module dependency strength calculation program executed on the computer. The inter-module dependency strength calculation program causes a computer to function as the source code acquisition unit 11, the global variable extraction unit 12, the access count measurement unit 13, and the dependency strength calculation unit 14. The computer includes a central processing unit (abbreviated as “CPU”) and a storage unit. The inter-module dependence strength calculation program is provided in a state where it is recorded on a recording medium so as to be readable by a computer.

  In the first embodiment, the processing target by the inter-module dependence strength calculation apparatus 10 is software including a plurality of modules. The software includes a plurality of modules, and each module includes source code 15 written in a programming language. Software includes software that has been free of programming defects, so-called bugs, software that is incomplete with bugs, and software that is in the middle of coding and whose functions are not yet complete. Including. The source code 15 in the software may be described in an object-oriented programming language such as C ++ and Java (registered trademark), for example, and is described in a structured programming language such as C language, Visual Basic, Fortran, or Kobol. It may be.

  The source code acquisition unit 11 acquires the source code 15 in units of modules by acquiring information representing the correspondence relationship information 16 between the source code and the module and the source code 15. The source code and module correspondence information 16 is stored in the form of a list in this embodiment. Hereinafter, the list representing the correspondence information 16 of the source code and the module may be referred to as a “correspondence list”.

  The acquired source code 15 is stored in the storage unit. The global variable extraction unit 12 extracts a plurality of types of global variables in each module and creates a global variable list 20. The global variable list 20 is a list that shows the extracted global variables in a list form for each module.

  Based on the source code and module correspondence information 16 acquired by the source code acquisition unit 11, the source code 15, and the global variable list 20, the access count measurement unit 13 accesses the global variable in each module. Count. The measured number of accesses is counted for each module and for each type of global variable, and is stored in the storage unit as access information 18.

  FIG. 2 is a flowchart showing each step of the inter-module dependence strength calculation method according to the first embodiment of the present invention. In the inter-module dependency strength calculation method in the first embodiment, the inter-module dependency strength calculation device 10 is used. The inter-module dependency strength calculation method includes a source code acquisition step, a global variable extraction step, an access count measurement step, and a dependency strength calculation step.

  In the source code acquisition step, the source code 15 is acquired in module units by the source code acquisition unit 11. In the global variable extraction step, the global variable is extracted by the global variable extraction unit 12. The global variables extracted in the global variable extraction process are global variables included in the source code 15 of at least some of the modules acquired in the source code acquisition process.

  In the access count measurement process, the access count measurement unit 13 measures the access count for at least some of the global variables extracted in the global variable extraction process for each global variable. The number of accesses is the number of accesses to a global variable of a plurality of modules. The plurality of modules are a plurality of modules among the modules subjected to the extraction of the global variable in the global variable extraction step.

  In the dependency strength calculation step, the dependency strength 19 between the plurality of modules is calculated for each global variable by the dependency strength calculation unit 14 based on the number of accesses. In the inter-module dependency strength calculation method, each of the above steps is performed in the order of a source code acquisition step, a global variable extraction step, an access count measurement step, and a dependency strength calculation step.

  FIG. 3 is a diagram illustrating an example of the source code 15 acquired by the source code acquisition unit 11 in the first embodiment of the present invention. FIG. 3 shows a part of the source code 15 acquired by the source code acquisition unit 11 in the first embodiment. The source code 15 acquired in the first embodiment includes more modules. Shall be included. In the description of this embodiment, it is assumed that simple source code 15 written in C language is given as input. In addition to the C language, the present invention is similarly applied to languages that can define global variables such as Fortran, C ++, Java (registered trademark), or languages that can define variables that can be accessed substantially equivalent to global variables. Is possible.

In FIG. 3, the configuration of the source code 15 includes a module 301 having a module name “module1” and a module 302 having a module name “module2”.
”Includes a source code 303 named“ M1_S1.c ”and a source code 304 named“ M1_S2.c ”, and a module 302 named“ module2 ”
This indicates that the source code 305 named “M2_S1.c” is included.

  In step a2 in FIG. 2, the contents of the source codes 303, 304, and 305 are acquired as the source code 15 together with the source code name. The source code and module correspondence information 16 is information that defines which source code 15 is included in which module, and is acquired, for example, in the form of a list shown in Table 1. However, in other embodiments, the way of expressing the source code and module correspondence information 16 is not limited to the format of the list shown in Table 1. When the file as the electronic data describing the source code 15 is referred to as a “source code file”, it is included in a folder with the name of a certain module using the folder structure on the file system where the source code file exists. An embodiment in which all source code files are automatically identified as source code 15 included in the module can be realized.

  FIG. 4 is a flowchart showing each stage of the global variable extraction process in the first embodiment of the present invention. In step a2 of FIG. 2, the global variable extraction unit 12 of FIG. 1 acquires the source code 15 from the source code acquisition unit 11, analyzes it, and uses the list of global variables defined in the source code 15 as a list. A global variable list 20 is generated.

  In step b1 in FIG. 4, it is checked whether all source code files given as inputs have been opened and analyzed. If all source code files have been opened, the process proceeds to step b13, and a global variable list 20 described later is output. If all the source code files have not been opened yet, the process proceeds to step b2, and one source code file that has not been opened is selected and opened as an analysis target.

  Next, the process proceeds to step b3, and information that takes one of the values “outside function definition” or “inside function definition” is set to “outside function definition” as information about the position in the source code 15 to be acquired. “In function definition” is information indicating that the function is defined in the source code 15, and “out of function definition” is information regarding the position in the source code 15. It means the information that it is outside the area that is performing. Next, the process proceeds to step b4, and the next one sentence is acquired in order from the currently opened source code file.

  Next, the process proceeds to step b5, and it is determined whether or not the variable definition is performed in one sentence acquired in step b4. The variable definition is usually described as “variable type name variable name, variable name, ...;” as shown in the third line of the source code 303 in FIG. 3 and the third line of the source code 304. Determine. As a result of the determination, if it is determined that the variable definition is performed, the process proceeds to step b6. If it is determined that the variable definition is not performed, the process proceeds to step b8.

  In step b6, it is determined whether or not the location where the variable definition is performed is outside the function definition, that is, whether or not the information about the position in the source code 15 to be acquired is “outside the function definition”. When the position information in the source code 15 is “outside function definition”, it is determined that the defined variable is a variable defined outside the function definition, that is, a global variable.

  Next, the process proceeds to step b7, and the variable determined to be a global variable is added to the global variable list 20. When the position information in the source code 15 is “within function definition”, it is determined that the defined variable is not a global variable, and the process proceeds to step b4 in order to obtain the next sentence.

  In step b8, it is determined whether or not there is a function definition start description in the acquired one sentence. The start of a function definition is usually described in the format of “function return value type function name (argument list)”, so it can be determined. As a result of the determination, if it is determined that there is a description of the start of the function definition, the process proceeds to step b9, the position information in the source code 15 is changed to “within the function definition”, and the next sentence is obtained. Therefore, the process proceeds to step b4. If it is determined in step b8 that the description is not the start of function definition, the process proceeds to step b10.

  In step b10, it is determined whether or not there is a description of the end of the function definition in the acquired one sentence. For example, in the case of C language, the function definition is described between “{” and “}”. Therefore, the end of the function definition can be determined by the presence or absence of the outermost closing parenthesis “}” when the position information in the source code 15 is “within the function definition”. As a result of the determination, if it is determined that there is a description of the end of the function definition, the internal state is changed to “out of function definition” in step b11, and the process proceeds to step b4 to obtain the next sentence. If it is determined in step b10 that the function definition is not ended, the process proceeds to step b12.

  In step b12, it is determined whether or not the end of the currently opened source code file has been acquired. If it is determined that it is not the end of the source code file, step b4 is executed to obtain the next sentence. If it is determined that the end of the source code file is reached, the process proceeds to step b1 to open another source code file that has not been opened.

  After the global variable extraction step shown in FIG. 4, that is, step a2 in FIG. 2 is completed, the process proceeds to the access count measurement step in step a3 in FIG. Then, the source code and module correspondence information 16 and the global variable list 20 from the global variable extraction unit 12 are acquired, and the access information 18 as illustrated in Table 2 is generated.

  As described above, the access information 18 is information indicating which global variable included in the source code 15 of each module is accessed, that is, written or read. The first row of the table lists global variables included in the source code file, and the first column lists modules included in the source code file. In the other column, the number of times of writing to the global variable “g” of the module “M” “W (M, g” is written in the square where the module (“M”) and the global variable (“g”) are orthogonal to each other. ) ”And the number of reads“ R (M, g) ”of the global variable“ g ”of the module“ M ”.

  FIG. 5 is a flowchart showing each stage of the access count measurement process in the first embodiment of the present invention. After the start of this process, it is determined in step c1 in FIG. 5 whether or not all modules have been processed. If all modules have been processed, the access information 18 is output in step c11 and the process ends. If all the modules have not been processed, a module that has not yet been processed is selected in step c2. The module selected in step c2 is referred to as “module M”.

  Next, in step c3, it is determined whether all the source code files included in the module M selected in step c2 have been opened. If all the source code files have been opened, the process proceeds to step c1 in order to process other modules. If all the source code files have not been opened yet, in step c4, the source code files that have not been opened are opened. Next, in step c5, the next one sentence is acquired in order from the currently opened source code file.

  Next, in step c6, it is determined whether or not writing to the global variable is performed in the acquired one sentence. The writing to the global variable may be expressed by a description in which the global variable is used on the left side of the assignment expression like the global variable “g_1” on the left side of the seventh line of the source code 304 in FIG. In addition, it may be expressed by a description indicating increment and decrement such as “g_1 ++” and “g_1--”.

  When writing to the global variable (referred to as “global variable g”) is performed, the number of times “W (M, g) of writing to the global variable g of the module M included in the access information 18 in step c7. "1" is added to "", and the process proceeds to the next step c8. The initial value of the write count “W (M, g)” to the global variable g of the module M is set to zero. Further, the process proceeds to step c8 when the global variable is not written.

  In step c8, it is determined whether the global variable is read in the acquired one sentence. The reading of the global variable is represented by a description in which the global variable is used on the right side of the assignment expression, for example, the global variable “g_1” on the right side of the 7th and 11th lines of the source code 305 in FIG. In some cases. In addition, it may be described as an operand of a comparison operator used in increment, decrement, conditional statements, etc., an argument when calling a function, a return value of a function, etc.

  If the global variable has been read, the process proceeds to the next step c9, and “1” is added to the read count “R (M, g)” of the global variable g of the module M included in the access information 18. Then, the process proceeds to the next step c10. The initial value of the read count “R (M, g)” of the global variable g of the module M is set to zero. If the global variable has not been read, the process proceeds to step c10.

  In step c10, it is determined whether or not the end of the open source code file has been read. If it is determined that it is not the end of the source code file, the process proceeds to step c5 to obtain the next sentence. If it is determined that the end of the source code file is reached, the process proceeds to step c3 to open another source code file that has not yet been opened.

  FIG. 6 is a diagram illustrating an access state of each global variable in each module according to the first embodiment of this invention. The number of accesses shown as an example in FIG. 6 matches the number of times shown in Table 2. In FIG. 6, the arrows extending from the squares (601, 602, 603) representing the modules to the ellipses (604, 605, 606) representing the global variables represent writing to the global variables in each module. An arrow extending from an ellipse (604, 605, 606) representing a global variable to a square (601, 602, 603) representing a module represents reading of the global variable in each module.

  When the source code 15 acquired by the source code acquisition unit 11 shows the access relationship shown in FIG. 6 as a result of the global variable extraction by the global variable extraction unit 12 and the access count measurement by the access count measurement unit 13. 4 and 5 is executed, the access information 18 shown in Table 2 is obtained.

  In step a2 of FIG. 2, the dependency strength calculation unit 14 of FIG. 1 acquires the access information 18 from the access count measurement unit 13 and calculates the inter-module dependency strength 19. The inter-module dependency strength 19 is a quantitative evaluation of the inter-module dependency strength 19 included in the source code 15. Table 3 shows an example of the inter-module dependency strength 19. Table 3 shows the dependency strength 19 between modules for one type of global variable, for example, “g”.

In the first row and the first column of Table 3, modules included in the source code file are listed. In the other columns, the dependency strength I (M1, M1) of the module “module2” with respect to the module “module1” is shown in a square where the row of the module “module1” and the column of the module “module2” are orthogonal to each other.
M2) is described. Therefore, Table 3 shows how much a certain module is affecting other modules or how much it is influenced by other modules.

  For example, as shown in the first row, when looking at Table 3 sideways, it can be seen how much “module1” affects other modules. Specifically, the influence of the writing to the global variable “g” in “module1” on the reading of the global variable “g” in another module is shown in each row of Table 3.

Also, when looking at the table vertically as shown in the second column from the left in Table 3, for example,
You can see how much module1 is affected by other modules. In particular,"
The influence given by reading the global variable “g” in “module1” from writing to the global variable “g” in other modules is shown in each column of Table 3.

  FIG. 7 is a flowchart showing each stage of the dependency strength calculation process in the first embodiment of the present invention. In step d1 of FIG. 7, it is determined whether or not processing has been performed for all combinations of modules included in the source code file. If all the combinations of modules have been processed, the process proceeds to step d9, the inter-module dependency strength is output as a calculation result, and the process ends. If all the combinations of modules have not been processed yet, the process proceeds to step d2, and a combination of modules not yet processed is selected. Hereinafter, steps d3 to d8 in FIG. 7 will be described assuming that modules “M1” and “M2” are selected in step d2.

  In step d3, a global variable list 20 is generated from the access information 18 for the common global variables that are written or read by the modules “M1” and “M2”. Hereinafter, this specific global variable list 20 is referred to as “list”. For example, when the access information 18 shown in Table 2 is given and “module 1” and “module 2” in Table 2 are selected as the modules “M1” and “M2”, the “module 1” is obtained from the access information 18 in Table 2. And a global variable list “list” is generated for the common global variables “g_1” and “g_2” written and read in “module2”.

  Next, the process proceeds to step d4, where it is determined whether or not all global variables in “list” have been processed. When processing has been performed for all global variables in “list”, d step d1 is executed to perform processing for another combination of modules. If all the global variables in “list” have not yet been processed, the process proceeds to step d5.

  In step d5, one global variable that has not yet been processed is sequentially acquired from “list”. If the specific global variable extracted in step d5 is “g”, for example, in the next step d6, the number of readings from the access information 18 to the global variable “g” in the modules “M1” and “M2”. Then, “R (M1, g)”, “R (M2, g)”, “W (M1, g)”, and “W (M2, g)” are acquired.

In the next step d7, the number of times of writing to the global variable “g” of the module “M1” “
The product of W (M1, g) ”and the number of reads“ R (M2, g) ”of global variable“ g ”of module“ M2 ”is the dependency strength of module“ M2 ”with respect to module“ M1 ”“ I (M1 , M2) ”. The initial value of the dependency strength “I (M1, M2)” of the module “M2” with respect to the module “M1” is zero.

  The product of “W (M1, g)” and “R (M2, g)” indicates that the more times module “M1” writes to global variable “g”, the more module “M2” has global variable “g” The larger the number of times “is read, the larger the value. If the number of writes to the global variable “g” in the module “M1” is doubled, the influence on the module “M2” that reads the global variable “g” is doubled. If the number of times of reading of the global variable “g” in the module “M2” is doubled, the influence of the module “M2” from the module “M1” written to the global variable “g” is doubled. Therefore, by finding the product of “W (M1, g)” and “R (M2, g)”, module “M2” is a global variable due to the effect of module “M1” on global variable “g”. The degree of influence received through “g” can be evaluated.

  Next, the process proceeds to step d8, where the number of writes “W (M2, g)” to the global variable “g” of the module “M2” and the number of reads “R (M1, g1) of the global variable“ g ”of the module“ M1 ”are performed. g) ”is added to the dependency strength“ I (M2, M1) ”of the module“ M1 ”with respect to the module“ M2 ”. The initial value of the dependency strength “I (M2, M1)” of the module “M1” with respect to the module “M2” is zero. When the access information 18 shown in Table 2 is given, the inter-module dependency strength 19 shown in Table 3 is obtained by executing the steps of FIG.

  According to the first embodiment, the access count measurement unit 13 obtains the access count for each global variable for at least some of the global variables extracted by the global variable extraction unit 12. The number of accesses is the number of accesses to a global variable in a plurality of modules. The dependency strength calculation unit 14 calculates the dependency strength 19 between the plurality of modules for each global variable based on the number of accesses.

  As a result, even when a plurality of types of global variables are used in the module source code 15 and the plurality of modules are related via the plurality of global variables, the dependency strength 19 between the plurality of modules is calculated. Can do. Therefore, the dependency strength 19 between modules can be quantitatively evaluated even for software created in a non-object-oriented programming language that does not support classes.

  Thereby, the inter-module dependence strength calculation apparatus 10 with high versatility can be realized. In addition, this makes it possible to find a module whose dependency relationship between modules is complicated when developing software including the source code 15 in module units. Therefore, it is possible to suppress the possibility of a decrease in software maintainability in software development due to the complicated dependency between modules.

  Further, according to the first embodiment, the dependency strength calculating unit 14 calculates the dependency strength 19 via the global variable of the remaining modules for one module. The dependency strength 19 is calculated based on the number of writes for the global variable in the one module and the number of reads for the global variable in the remaining modules.

  Thereby, the dependency strength 19 of the remaining module with respect to one module among the plurality of modules can be calculated with respect to the global variable. Therefore, the magnitude of the influence between the plurality of modules can be quantitatively evaluated by distinguishing the module on the influence side from the module on the influence side via the global variable.

  Further, according to the first embodiment, the dependency strength calculating unit 14 calculates the dependency strength 19 related to the global variable of the remaining modules for one module among the plurality of modules to be subjected to the access count measurement. It is calculated as the product of the number of writes for the global variable in the module and the number of reads for the global variable in the remaining modules. Thereby, the influence between modules can be evaluated quantitatively according to the number of times of writing and the number of times of reading.

  A module that writes to a global variable affects other modules that read this global variable, and the degree of the effect increases as the number of writes and reads increases, so the remaining for one module Can be quantitatively evaluated according to the number of times of writing and the number of times of reading.

  Further, according to the first embodiment, in the access count measuring step, the access count is measured for each global variable by the access count measuring section 13 for at least some of the global variables. In the dependency strength calculation step, the dependency strength 19 between the plurality of modules is calculated for each global variable by the dependency strength calculation unit 14 based on the number of accesses.

  As a result, even when a plurality of types of global variables are used in the module source code 15 and the plurality of modules are related via the plurality of global variables, the dependency strength 19 between the plurality of modules is calculated. Can do. Therefore, the dependency strength 19 between modules can be quantitatively evaluated even for software created in a non-object-oriented programming language that does not support classes. Thereby, the inter-module dependence strength calculation apparatus 10 with high versatility can be realized.

  In addition, this makes it possible to find a module whose dependency relationship between modules is complicated when developing software including the source code 15 in module units. Therefore, it is possible to suppress the possibility of a decrease in software maintainability in software development due to the complicated dependency between modules.

  Further, according to the first embodiment, the inter-module dependency strength calculation program causes the computer to function as the source code acquisition unit 11, the global variable extraction unit 12, the access count measurement unit 13, and the dependency strength calculation unit 14. As a result, the computer can function as the inter-module dependence strength calculation device 10. The inter-module dependence strength calculation program is provided to the computer in a state recorded on a recording medium, and the inter-module dependence strength calculation program is recorded on the recording medium so as to be readable by the computer. Thus, the inter-module dependence strength calculation program can be provided by a computer-readable recording medium.

(Second Embodiment)
The inter-module dependency strength calculation device 10 according to the second embodiment is similar to the inter-module dependency strength calculation device 10 according to the first embodiment, and hereinafter, the differences between the second embodiment and the first embodiment are mainly described. Explained. The access count measurement unit 13 in the second embodiment measures the number of accesses to global variables in the two modules for each global variable for all global variables included in the source code 15 of the two modules. The two modules are two of the modules from which global variables are extracted by the global variable extraction unit 12. The dependency strength calculation unit 14 calculates the total dependency strength of the other module with respect to one of the two modules. The overall dependency strength is obtained by summing the dependency strength 19 of the other module with respect to one module with respect to all global variables included in the source code 15 of these two modules.

  Thus, the influence of one module and the other module can be comprehensively evaluated with respect to all global variables included in the source code 15 of these two modules. As a result, when developing software including the source code 15 in module units, it is possible to find a module having a complicated dependency relationship between modules. Therefore, in software development, the possibility of software maintainability degradation can be suppressed.

(Third embodiment)
The inter-module dependency strength calculation device 10 according to the third embodiment is similar to the inter-module dependency strength calculation device 10 according to the first embodiment, and hereinafter, the differences between the third embodiment and the first embodiment are mainly described. Explained. The inter-module dependence strength calculation apparatus 10 according to the third embodiment further includes a module display unit and an input unit. The module display unit displays the module from which the global variable is extracted by the global variable extraction unit 12. The input unit is used to input information indicating a plurality of selected modules among the modules displayed on the module display unit and information indicating at least one of the plurality of selected modules. The dependency strength calculation unit 14 calculates the overall dependency strength of the remaining modules with respect to the at least one module in the selected plurality of modules.

  The module display unit is realized by a display device such as a liquid crystal monitor. In a state where a plurality of global variables are displayed on the display screen of the module display unit, the operator of the inter-module dependence strength calculating apparatus 10 can select some of the global variables. It is assumed that a plurality of selected global variables can be selected. Further, one module is selected as a separate display or on the switched display screen.

  The inter-module dependence strength calculation device 10 automatically calculates the total dependence strength between modules when the operator finishes inputting a plurality of modules and one of them. If the operation of selecting and inputting one module is repeated a plurality of times by the operator, the total dependence strength of the other modules for each of the plurality of modules can be calculated.

  With such a configuration, it is possible to input information of a plurality of selected modules by operating the input unit while checking the module display unit. Further, information indicating at least one module among the plurality of selected modules can be input via the input unit. Accordingly, the overall dependence strength of the remaining modules with respect to at least one module can be calculated by paying attention to a plurality of modules in the selected range. Therefore, when developing software, a module having a complicated dependency relationship between modules can be found within a range of a plurality of selected modules. As a result, it is possible to quickly find a module in which the dependency relationship between the modules is complicated as compared with the case where the inter-module dependency strength 19 is obtained for all the modules.

(Modification)
In the first embodiment, modules for which the dependency strength 19 is calculated are “module1” to “module1”.
Although the case of three of “module3” is illustrated, it is not limited to three. The number of modules corresponding to the calculation of the dependency strength 19 may be any number corresponding to an integer of 2 or more. The modules for which the dependency strength 19 is to be calculated may be a part or all of the modules from which global variables are extracted by the global variable extraction unit 12.

  In the first and third embodiments, the global variable related to the calculation of the dependency strength 19 by the dependency strength calculation unit 14 may be a part of the global variables extracted by the global variable extraction unit 12. Or all of them. In calculating the dependency strength 19 by the dependency strength calculation unit 14, it is possible to use all of the access counts measured by the access count measurement unit 13 or only a part of them.

  In the first to third embodiments, the global variable extraction module 12 may be a part of the module from which the source code 15 has been acquired, or all of the modules. Also good.

  Further, in the first to third embodiments, information that cannot be obtained unless the software that is the target of the dependency strength calculation by the module dependency strength calculation device is executed can be ignored. For example, in the definition of an array variable, an array variable for which the upper limit of the number of array variables is not defined, a global variable that refers to an index variable, a pointer to a static variable whose pointer value is changed, etc. Since the specific value can be changed, the inter-module dependence strength calculation apparatus 10 ignores it. For software that assumes that the address indicated by the pointer is not changed, a pointer that is commonly referenced in a plurality of modules can be handled as a global variable.

DESCRIPTION OF SYMBOLS 10 Inter-module dependence intensity | strength calculation apparatus 11 Source code acquisition part 12 Global variable extraction part 13 Access frequency measurement part 14 Dependence intensity calculation part 15 Source code 16 Correspondence relation information 18 Access information 19 Dependency intensity 20 Global variable list

Claims (6)

A source code acquisition unit for acquiring source code in module units;
A global variable extraction unit that extracts global variables included in the source code of at least some of the modules acquired by the source code acquisition unit;
Access for measuring, for each global variable, the number of accesses to the global variable in a plurality of modules among the at least some of the global variables extracted by the global variable extraction unit. Counting unit,
A dependency strength calculating unit that calculates a dependency strength between the plurality of modules whose access count is measured by the access count measuring unit for each global variable based on the access count. Calculation device. The access count measurement unit, as the number of accesses, sets the number of writes to the global variable in one module and the number of reads to the global variable in the remaining modules among the plurality of modules to be subjected to access count measurement. Measure and
The dependency strength calculation unit sets the dependency strength of the remaining modules for the one module via the global variable to the number of writes to the global variable in the one module and the number of reads to the global variable in the remaining module. The inter-module dependence strength calculating apparatus according to claim 1, wherein the inter-module dependent strength calculating apparatus calculates the inter-module dependence strength.   The dependency strength calculation unit is configured to determine the dependency strength of a remaining module for one module among the plurality of modules with respect to the global variable, the number of times of writing to the global variable in the one module, and the global variable in the remaining module. The inter-module dependence strength calculation apparatus according to claim 2, wherein the calculation is performed as a product of the number of reading times. The access frequency measurement unit may include the global variables in the two modules for all global variables included in the source code of two modules among the at least some modules from which the global variables are extracted by the global variable extraction unit. Measure the number of accesses to the variable for each global variable,
The dependence strength calculating unit is a total dependence strength of the other module with respect to one of the two modules,
The total dependency strength obtained by summing the dependency strength of the other module with respect to one module with respect to all global variables included in the source code of these two modules is calculated. The inter-module dependence strength calculation apparatus according to any one of the above. Using the inter-module dependence strength calculation device according to any one of claims 1 to 4,
A source code obtaining step of obtaining source code in module units by the source code obtaining unit;
Of the modules acquired in the source code acquisition step, a global variable extraction step of extracting global variables included in the source code of at least some modules by the global variable extraction unit;
Of the global variables extracted in the global variable extraction step, for at least some of the global variables, the number of accesses to the global variables in a plurality of modules of the at least some of the modules is determined by the access count measurement unit. Access count measurement process to measure for each variable,
A dependency strength calculation step of calculating, for each global variable, the dependency strength between the plurality of modules whose access count has been measured in the access count measurement step based on the access count by the dependency strength calculation unit. The inter-module dependency strength calculation method. Computer
Source code acquisition unit that acquires source code in module units,
A global variable extraction unit that extracts global variables included in the source code of at least some of the modules acquired by the source code acquisition unit;
Access for measuring, for each global variable, the number of accesses to the global variable in a plurality of modules among the at least some of the global variables extracted by the global variable extraction unit. A frequency measurement unit, and a dependency strength calculation unit that calculates the dependence strength between the plurality of modules whose access count is measured by the access count measurement unit for each global variable based on the access count. Inter-module dependency strength calculation program.

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