JPH06309175A - Program execution system for interpreter - Google Patents

Abstract

PURPOSE:To start a program without waiting for the end of compilation by using a pointer indicating whether the intermediate language program is already compiled or not to perform discrimination. CONSTITUTION:When the value of a program counter 14 is larger than the value of a second pointer 13 as the result of comparison of a comparing means 15 in an interpreter part 1, a compiling means 10 is called. This means 10 takes out a source language program in a source language program storage part 2 indicated by a first pointer 12 and analyzes it to generate the intermediate language program and stores it in an intermediate language program storage part 3, and first and second pointers 12 and 13 are updated by a pointer update means 16. If the value of the program counter 14 is larger still as the comparison result of the comparing means 15 thereafter, the comprising means 10 is called to perform the same processing. When the value of the program counter 14 is smaller than or equal to the value of the second pointer 13, an interpreter means 11 is started.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interpreter program execution system. In recent years, with the spread of computer systems, the demand for programming by end users is increasing. Therefore, some programming languages for end users, such as macro languages and script languages, are provided.

In many cases, such programming by the end user is performed by trial and error, such as writing and executing, and correcting and executing again if incorrect.
Therefore, instead of the method of executing through the steps of compiling, linking, and executing like the programming language for programmers, the method of interpreting and executing directly by an interpreter is suitable. In addition, since the created program is used as it is during operation, it must have excellent execution performance.

[0003]

2. Description of the Related Art The conventional interpreter has the following methods. A method of directly interpreting and executing a source language program.

A method of compiling a source language program to generate an intermediate language program, and then interpreting and executing the intermediate language program. Each time the above method loads a source language program,
In the method, the program is executed while interpreting it, and in the method, the compiler generates an intermediate language program and then executes it.

[0005]

According to the above method, since the source language program is executed while interpreting it every time, there is no problem when the amount of source language program is small, but there is no problem when the amount is large. When there is a loop in, there is a problem that the execution speed is slow because it is necessary to execute the same interpretation for the same code each time. Further, according to the method (1), if the intermediate language program (compiler) does not exist (is not prepared at the time of execution), it has to be compiled once, and it takes time to start the execution.

According to the present invention, in a method of compiling a source language program to generate an intermediate language program and then interpreting and executing the intermediate language program, it is possible to shorten the time until the start of execution when the intermediate language program does not exist. To aim.

[0007]

FIG. 1 is a diagram for explaining the principle of the present invention. In FIG. 1, 1 is an interpreter unit of the information processing apparatus, 2 is a source language program storage unit in which a source language program is stored, and 3 is an intermediate language program storage unit in which an intermediate language program as a result of compilation is stored.

In the interpreter unit 1, 10 is a compiling unit, 11 is an interpreter unit, 12 is a first pointer indicating a program position in the source language program storage unit, and 13 is an intermediate language program. Is a second pointer indicating whether or not is created, 14 is a program counter (PC) indicating an instruction being interpreted and executed by the interpreter means, 15 is a comparing means,
Reference numeral 16 is a pointer updating means, and 17 is a program counter (PC) updating means.

According to the present invention, a compiled program is managed by a pointer, and whether or not the intermediate language program to be executed has been compiled is determined by using the pointer. When the intermediate language program does not exist, the program is immediately compiled. Is to go and execute.

[0010]

In FIG. 1, the first pointer 12 of the interpreter unit 1 holds a pointer value indicating to what position on the source language program storage unit 2 has been read and compiled (interpreted) by the compiling means 10 so far. . The second pointer 13 holds the position on the intermediate language program storage unit 3 created by the compiling means 10 up to the present. In addition, the program counter (PC) 14
Holds the position of the intermediate language program storage unit 3 executed by the interpreter means 11 up to the present.

In the interpreter unit 1, first, the value of the program counter 14 and the second pointer 13 by the comparison unit 15 are compared.
Compare the values of. By this comparison, the program counter 1
When the value of 4 is larger than the value of the second pointer 13, the compiling means 10 is called.

The compiling means 10 includes a first pointer 1
The source language program indicated by 2 is extracted from the source language program storage unit 2 and analyzed to create an intermediate language program, which is stored in the intermediate language program storage unit 3. After the intermediate language is created, the pointer updating means 16 is driven to update the first pointer 12 and the second pointer 13. If the comparison result by the comparison means 15 is still larger than the value of the program counter 14 after this update, the compiling means 10 is continuously called and the same operation is performed.

When the value of the program counter 14 is smaller than or equal to the value of the second pointer 13 as a result of the comparison by the comparison means 15, the interpreter means 11 is activated.
The interpreter means 11 fetches and executes the intermediate language program instructed by the program counter 14 on the intermediate language program storage section 3. Post-execution PC updating means 1
7 is driven, the program counter 14 is updated,
If the updated value of the program counter 14 is still smaller than or equal to the value of the second pointer 13, the interpreter means 11 similarly executes the program.

[0014]

FIG. 2 is a block diagram of an embodiment. In FIG. 2, 20 is a processing device (CPU and memory), 21 is a compiler, 22 is an interpreter, 23 is an area on the memory into which an intermediate language program is loaded, and 24-26 correspond to 12-14 of FIG. Reference numeral 24 is a pointer indicating the reading position of the source language program, 25 is a pointer indicating how far the intermediate language program is created, 26 is a program counter (PC) indicating the instruction being interpreted and executed by the interpreter 22, and 27 is the source language program. The stored source file 28 is an intermediate language file storing an intermediate language program.

FIG. 3 is a processing flow of the embodiment, which is executed by the interpreter 22 in the configuration shown in FIG. 2 and its contents will be described below. First, it is determined whether the intermediate language file 28 exists (S1 in FIG. 3), and if it exists, the intermediate language file 28 is loaded into the load area 23 on the memory of the processing device 20 (S2 in FIG. 3). After that, the value of the pointer 25 is set to a value representing the end of the intermediate language program in the load area 23 (at step S3). If there is no intermediate language file, the source file 27 is opened (at step S4), and the pointers 24 and 25 are set to the values at the head positions (at step S5). After that, the program counter (PC) is set to the head position of the load area 23 of the intermediate language program (at step S6), and the execution of the program is started.

Next, it is determined whether the value of the program counter (PC) 26 is smaller than the value of the pointer 25 (see the same S
7). Here, when the intermediate language program is loaded from the intermediate language file 28 by the above steps S2 and S3, the pointer 25 is the program counter (P
Yes because it is larger than the value of C). In this case, the intermediate code (intermediate language program) indicated by the program counter (PC) 26 is executed to update the program counter (PC) 26 (at step S10).

If there is no intermediate language file, the values of the pointer 25 and the program counter (PC) 26 coincide with each other in steps S4 to S6.
Is determined to be NO, the statement pointed to by the pointer 24 is taken out from the source file 27, compiled by the compiler 21, the obtained intermediate language code is stored in the load area 23 (at step S8), and the pointers 24, 25 are updated. (S9 of the same). Then, the intermediate code pointed to by the PC is executed to update the program counter 26 (at step S10).

Subsequently, it is determined whether the program counter (PC) has reached the end of the intermediate code (at step S11), and if it has not reached the end, the process returns to step S7 and the same processing as above is executed to execute the program. When the counter (PC) 26 reaches the end of the intermediate code, it ends.

[0019]

According to the present invention, even if the intermediate language is not generated, the execution of the program can be started without waiting for the end of the compilation, and the time until the start of execution can be shortened as compared with the conventional case. can do. Therefore, operability can be improved when trial and error programming is performed.

[Brief description of drawings]

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

FIG. 2 is a configuration diagram of an embodiment.

FIG. 3 is a processing flow of an embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 interpreter unit 2 source language program storage unit 3 intermediate language program storage unit 10 compiler means 11 interpreter means 12 first pointer 13 second pointer 14 program counter (PC) 15 comparing means 16 pointer updating means 17 program counter (PC) Update means

Claims (3)

[Claims] 1. A program execution method of an interpreter comprising a compiling means for interpreting and executing a source language program or an intermediate language program, the source language program storage section and the intermediate language program storage section,
Holding means for the program position in the source language program storage unit that has been interpreted up to the present, execution position of the program in the source language program storage unit, and an intermediate language program created by interpreting the source language program. If the position of the executed program is smaller than the position of the executed program by the comparing unit, the program in the intermediate language program storage unit designated by the program counter is executed to change the position of the executed program. A program execution method of an interpreter, characterized in that, if the position of the created intermediate language program is equal to or larger than the position, the intermediate language program is created and executed from the source language program by the compiling means. 2. The first pointer according to claim 1, which holds a position of how much the source language program has been interpreted, and the second pointer which holds a position of how much the intermediate language program has been created. A program execution method for an interpreter, comprising: a program counter that indicates the position of an intermediate language program that has been executed. 3. The intermediate language file storing the intermediate language program according to claim 1, wherein the intermediate language file is loaded into a memory, and the last position of the loaded intermediate language program is loaded into the second pointer. An interpreter program execution method characterized by setting