JPH0399330A - Procedure in-line development system - Google Patents

Abstract

PURPOSE:To improve the execution efficiency of an object program by deciding the validity of in-line development from the information of a procedure block information table, and when the development is valid, executing the in-line development. CONSTITUTION:A procedure block detecting means 42 detects an internal procedure block from an intermediate text 31 and registers a procedure block name and a file position in a procedure block information table 41 and a procedure block reference frequency detecting means 43 detects the access of the internal procedure block and registers the reference frequency in the table 41. A procedure block in-line developing means 44 decides the validity of in-line development for the access of each internal procedure block from the information of the table 41 and executes the in-line development when it is valid. Since processing to be required for subroutine linkage or the like can be omitted at the time of executing an object program, the execution efficiency of the object program can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a procedure inline expansion method in an optimization section of a compiler.

[Conventional technology]

Conventionally, in compilers that generate object programs from source programs written in high-level languages,
After transforming the source program into intermediate text, it is converted into the corresponding code, and the calling part of the internally defined procedure block (internal procedure block) is an object for prologue processing and epilogue processing to perform subroutine linkage, etc. It was considered a code.

[Problem to be solved by the invention]

Conventional compilers process calls to internal procedure blocks as described above, which has the disadvantage of poor execution efficiency due to subroutine linkage.

The present invention has been proposed in view of the above points, and its purpose is to provide a procedure inline expansion method that can improve the execution efficiency of object programs.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a procedure block information table that has an entry for each internal procedure block, and each entry has items such as procedure block name, file position, and number of references, and intermediate text. a procedure block detection means for detecting an internal procedure block and registering a procedure block name and a file location in the procedure block information table; detecting a call to the internal procedure block from intermediate text and recording the number of references in the procedure block information table; A means for detecting the number of references to a procedure block to be registered; and a procedure block inline expansion means for determining whether or not inline expansion is possible based on information in the procedure block information table for a call to each internal procedure block, and performing inline expansion if possible. I'm trying to prepare.

[Effect]

In the procedure inline expansion method of the present invention, the procedure block detection means detects the internal procedure block from the intermediate text and registers the procedure block name and file position in the procedure block information table, and the procedure block reference count detection means detects the internal procedure block from the intermediate text and registers the procedure block name and file position in the procedure block information table. A call to an internal procedure block is detected from the intermediate text, the number of references is registered in the procedure block information table, and the procedure block inline expansion means determines whether inline expansion is possible for each internal procedure block call from the information in the procedure block information table. Determine and inline expansion when possible.

〔Example〕

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

FIG. 1 is a block diagram showing an embodiment of a compiler to which the procedure inline expansion method of the present invention is applied. In FIG. 1, the present embodiment includes a front end section 2 which inputs a source program 1 and outputs an intermediate text 31 to an intermediate text file 3, and a front end section 2 which inputs a source program 1 and outputs an intermediate text 31 to an intermediate text file 3; an optimization unit 4 that outputs processed intermediate text) 51 to a file 5, and a processed intermediate text 51 from the processed intermediate text file 5;
It is comprised of a back-end section 6 that receives input and outputs an object program 7, and a control section 8 that controls each functional section.

The optimization unit 4 also uses a procedure block information table 41.
and procedure block detection means 42, procedure block reference count detection means 43, and procedure block inline expansion means 4.
It is composed of 4.

The functions of each part are as follows.

Procedure block information table 41: As shown in FIG. 2, it has an entry 411 for each internal procedure block included in the intermediate text 31, and each entry contains items such as procedure block name, file location, and number of references. have

Procedure pronk detection means 42; has a function of detecting an internal procedure block from the intermediate text 31 and registering the procedure block name and the file position of the internal procedure block in the intermediate text file 3 in the procedure block information table 41. .

Procedure block reference count detection means 43; intermediate text 3
1, it has a function of detecting calls to internal procedure blocks and registering the number of references in the procedure block information table 41.

Procedure block inline expansion means 44; has a function of determining whether or not inline expansion is possible based on the information in the procedure block information table 41 for a call to each internal procedure block, and performing inline expansion if possible.

The operation of the above embodiment will be explained below.

When the compiler is activated, the control unit 8 activates the front end unit 2 → the optimization unit 4 → the back end unit 6 in this order. Also, the same is true within the optimization unit 4 (control unit 8
Accordingly, the procedure block detection means 42→procedure block reference count detection means 43→procedure block inline expansion means 44 are activated in this order.

First, the front end unit 2 inputs the source program 1, performs processing such as syntax analysis, and outputs intermediate text 31 to the intermediate text file 3.

Next, the procedure block detection means 42 of the optimization unit 4 inputs the intermediate text 31 from the intermediate text file 3,
When the start of an internal procedure block is detected, the procedure block name and file position on the intermediate text file 3 are registered in the procedure block information table 41. Also, initialize the number of references.

Next, the procedure block reference count detection means 43 inputs the intermediate text 31 from the intermediate text file 3, and when detecting a call to an internal procedure block, searches for the corresponding procedure block name from the procedure block information table 41 and determines the reference count. Add 1 to the item value.

After the above processing, procedure block inline expansion means 4
4 is activated and performs the processing shown in FIG.

That is, the procedure block inline expansion means 44 reads one text of the intermediate text 31 from the intermediate text file 3 (step SL), and determines whether or not it is a call to an internal procedure block (step S2).
If not, the read intermediate text 31 is output as it is to the processed intermediate text file 5 as the processed intermediate text 51 (step 33). Note that if the file ends, the process ends.

In addition, if the read text is a call to an internal procedure block, the procedure block information table 41
Step S4: Search for the corresponding procedure block name from
), it is determined whether the value of the reference count item is less than a predetermined value n (step S5), and if it is greater than n, the read intermediate text 31, that is, the intermediate text corresponding to the calling instruction of the internal procedure block has been processed as is. It is output to the processed intermediate text file 5 as intermediate text 51 (step S3). That is, if the number of references is too large, the size of the object program 7 will become enormous due to inline expansion, so the objects of inline expansion are limited to those whose number of references is less than n.

On the other hand, if the number of references is less than n, the current file position is saved, and the intermediate text file 3 is pointed to using the file position of the internal procedure block in the procedure block information table 41 (step S6). One text of intermediate text 31 is read from the file position (step S7).

Next, it is determined whether the internal procedure block has ended or not (Step S8), and if it has not ended, it is determined whether the text is for prologue processing or epilogue processing (Step 5lO), and it is not text for prologue processing or epilogue processing. In that case, the intermediate text 3
1 to the processed intermediate text file 5 as the processed intermediate text 51), step S7
Return to If the text is for prologue processing or epilogue processing, the process returns to step S7 without outputting it to the processed intermediate text file 5. Then, when the internal procedure block is completed, the process returns to step S9) in which the file position is restored to the original position, and then the process returns to step S1.

As a result of the above processing, prologue processing is performed for internal procedure blocks whose number of references is less than the predetermined value n.

Only the text of the main body portion excluding the text for epilogue processing is outputted to the processed intermediate text file 5 as processed intermediate text 51.

This is inline expansion.

Next, the back end unit 6 inputs the processed intermediate text 51 from the processed intermediate text file 5, performs code generation, etc., and outputs the object program 7.

〔Effect of the invention〕

As explained above, in the procedure inline expansion method of the present invention, it is decided whether or not to perform inline expansion in consideration of the number of references to an internal procedure block, and if possible, prologue processing and epilogue processing are not included. Since the contents of the internal procedure block itself are expanded as code,
This eliminates the need for processing required for subroutine linkage and the like when executing an object program, resulting in a significant improvement in execution efficiency.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a compiler to which the procedure inline expansion method of the present invention is applied, FIG. 2 is a detailed diagram of the procedure block information table in FIG. 1, and FIG. 3 is a diagram showing the procedure in FIG. 1. It is a flowchart of the processing of a block inline expansion means. In the figure, 1... Source program 2... Front end section 3... Intermediate text file 31... Intermediate text 4... Optimization section 41.・Procedure block information table 42 ・Procedure block detection means 43 ・Procedure block reference count detection means 4 ・Procedure block inline expansion means ・Processed intermediate text file ・Processed intermediate Text: Backend section: Object program: Control section

Claims (1)

[Scope of Claims] A procedure block information table having an entry for each internal procedure block, each entry including a procedure block name, file location, and number of references, and detecting an internal procedure block from intermediate text. a procedure block detection means for registering a procedure block name and a file location in the procedure block information table; and a procedure block reference for detecting a call to an internal procedure block from intermediate text and registering the number of references in the procedure block information table. The present invention is characterized by comprising: a number of times detection means; and a procedure block inline expansion means that determines whether or not inline expansion is possible based on information in the procedure block information table for calls to each internal procedure block, and performs inline expansion if possible. Procedure inline expansion method.