JPH02171830A - Optimum data allocating system in compiler - Google Patents

Abstract

PURPOSE:To eliminate the need for the output and the calculation of an excess purpose program for the approach of a data and to improve the translating speed of a source program by allocating the data in the order of the data having the large number of times of reference. CONSTITUTION:The front end part 2 of a compiler 1 inputs a source program 7 and outputs an intermediate language 8 and allocation order information 9. As a role in this front end part 2, the analysis of a procedure part in the source program 7, which is written by a user, is charged in a procedure analyzing part 3 and the allocation order information 9 are arranged in the analyzing part 3 by the reference number of times of order arranging means 4 according to the order of the number of times of reference. A reference number of times of order data allocating means 5 really executes the allocation processing of the data based on the information 9 and the means 5 is positioned between the front end part 2 and a back end part 6. This back end part 6 inputs the intermediate language 8 and executes code generation and the output of a purpose program 10. Then, the translating speed of the source program is improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a compiler for a computer system, and in particular, allocates a base address to be a base point at intervals of maximum displacement, sets the base address in a base register, and calculates the relative value from the base address. The ubiquitous data allocation in a computer system compiler that accesses data by setting an address in an index register or displacement is related to a method.

[Conventional technology]

Conventionally, the data allocation method in this type of compiler is that data allocation is performed in the order of data declaration in the source program, and the data declarations are made in the order of data D, data B, data C, data A, and data E. Assuming that data is allocated to the data area 71 in the order of data D, data B, data C, data A, and data E, as shown in FIG. For this reason,
To access data A and data B, set address C to base register # for data access of data A.
2 and an instruction to load address b into Heath Regisc #1 for data access of data f3 had to be output.

[Problem to be solved by the invention]

In the data allocation method in the conventional compiler described above, if unreferenced data or data with few references is declared first, there is a possibility that data with many references will be allocated to an area larger than the maximum displacement of the data area. Therefore, if data that is frequently referenced is allocated to an area that exceeds the maximum displacement of the data area, outputting a load instruction to the base register to access the data, calculating a relative address from the base register, etc. The disadvantage is that the processing has to be done during translation, which slows down the translation speed of the source program.

Furthermore, since the number of steps in the target program increases, there is a drawback that the efficiency of executing the target program decreases.

In particular, the above drawback becomes significant when data with many references are scattered and declared among data with no or few references.

In view of the above-mentioned points, an object of the present invention is to allocate data to a data area in the order of the data that has been referenced the most, thereby eliminating the need for outputting or calculating an unnecessary objective block 1:1 gram for data access, and providing a source program. It is an object of the present invention to provide a method for universal data allocation in a compiler that speeds up the translation speed of the program and also speeds up the execution speed of the target program.

[Means to solve the problem]

The method of universal data allocation in the compiler of the present invention is as follows:
In the compiler of a computer system, data is accessed by assigning the base point pace address at the maximum displacement interval, setting the pace address in the base register, and setting the relative address from the base address in the index register or displacement. A pointer value to a data symbol table is obtained, and the pointer value is arranged in descending order of the number of times the data is referenced, and the allocation is used as order information. The method includes means for inputting information, identifying the layout order information, and allocating data in descending order of the number of references.

[Effect]

The compiler of the present invention has a method for repeating data allocation, in which a reference count sorting means obtains a pointer value to the symbol table of each data, sorts the pointer values in descending order of the number of times the data has been referenced, and the allocation is treated as order information. For data allocation in the order of the number of references, the means inputs order information for the arrangement sorted by the number of references j first by the arrangement means, and performs data allocation from data with the highest number of references based on the order information.

〔Example〕

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

FIG. 1 is a block diagram showing the configuration of a compiler 1 to which a repeatable data allocation method according to an embodiment of the present invention is applied. This compiler 1 is composed of a front end section 2 having a procedure section analysis section 3 including a reference number sorting means 4, a reference number order data allocation means 5, and a bank end section 6.

The front end unit 2 inputs the source program 7 and outputs the intermediate language 8 and layout f19. There are parts in the front end part 2 that share various roles, but the procedure part analysis part 3 is mainly responsible for analyzing the procedure part of the source program 7 written by the user. In the procedure division analysis section 3, there is provided a reference number class sorting means 4 for arranging the allocation order information 9 into reference number classes.

Means 5 is for data allocation in order of number of references, allocation is Junjo+'19
Data allocation is actually a means of processing based on
It is located between the front end section 2 and the back end section 6.

The bank end unit 6 receives the intermediate language 8 output from the front end unit 2, and mainly performs code generation and output of the target program IO.

Referring to FIG. 2, the processing in the procedure division analysis unit 3 including the reference count sorting means 4 includes a procedure division reading step 21, a procedure division end determination step 22, an intermediate language generation step 23, and a symbol table acquisition step. 24, the highest level data determination step 25, the highest level data symbol table acquisition step 26, the registration bit on determination step 27, and the reference count increment step 2
8 and address registration and registration bit on step 29
The allocation consists of a step 30 of arranging the order information in order of the number of times of reference.

Referring to FIG. 3, the processing in the means 5 for data allocation in order of number of references and the step 31 for symbol table data allocation.

Next, the operation of the continuous data allocation system of this embodiment configured as described above will be explained.

The front end part 2 of the compiler l is the source program 7
, the procedure division analysis unit 3 inputs the source program 7
A unit of the procedure division (e.g., a unit of transcription, comparison, etc.)
is read (step 21), and if the procedure section is not finished (step 22), an intermediate language 33B for the read one unit is generated (step 23).

Next, the procedure division analysis unit 3 obtains a symbol table of data related to the generated intermediate language 8 (step 24). For example, if the user writes "A-B" in the procedure division of the source program 7, and this description is the language specification of the source program 7 that assigns the contents of data B to data A, the generated intermediate language The information that 8 is a transcription is associated with the symbol table for data and the symbol table of data B.

Next, the procedure division analysis unit 3 checks whether the data is the data with the highest level number (top level data) from the obtained symbol table (step 25), and determines whether the data is the data of the subordinate level. (data other than the highest level data), obtain a symbol table of the data with the highest level number (step 26). This is done by attaching the data with the highest level number to 11. This is because for the first time, the address of data allocation at a level subordinate to that data is determined.

The symbol table of the data with the highest level number obtained in this way has bits whose initial value is off (hereinafter referred to as registered bits), and the procedure division analysis unit 3 analyzes the registered bits. Check whether it is in the initial state (off) (step 27), and if it is in the initial state, the address of the symbol table is registered in the order information 9 as a pointer to the symbol table.
For the first reference, set the initial value ``1'' to the number of references in the order information 9, save the pointer (address) to the allocation in the symbol table, and turn on the registration bit. (Step 29).

For example, as shown in FIG. 4, the symbol tables 41, 42, 43 and 44 for data D, data B, data C and data A are registered in the order information 9, and then data E is referenced. In this case, the address of the symbol table 45 of the data E will be registered as a pointer to the fifth symbol table of the allocation order information 9.

If the registration bit is on in step 27, indicating that the symbol table has been registered in the allocation order information 9, the allocation saved in the symbol table at the first reference is a pointer to the order information. For the corresponding allocation, obtain the order information 9 and set the number of references to 1.
count up (step 28).

After repeating this series of operations and completing the procedure division of the source program 7 (step 22), the procedure division analysis unit 3 uses the reference count sorting means 4 to sort the number of references by 1.
The layouts in which all the data for more than 10 times have been registered are arranged in descending order of the number of times of reference using the order information 9 as the key of the number of times of reference (step 30).

For example, if the only data referenced in the procedure division of source program 7 is data A, data B, data C, data D, and data E, the allocation will be registered in Junjo@9 for 5 of these data. There are only one symbol table 41 to 45, and when these are arranged in order of the number of references, the layout is 1111 as shown in FIG. 5! r information 9 is obtained. Here, since the symbol tables 41 to 45 no longer refer to the order information 9 for allocation, the pointers to the order information for the allocation of the symbol tables 41 to 45 are cleared to NULL at the same time.

When the processing in the front end unit 2 is completed, the data allocation means 5 in the order of the number of references inputs the order information fH for the data sorted by the number of references sorting means 4, and allocates the data in order of the number of references (step 51). ).

As a result, the data area 61 to which data is allocated is
For example, as shown in FIG.
The instruction to load address a, which indicates the beginning of There is no need to output load instructions.

〔Effect of the invention〕

As explained above, the present invention has the effect that by allocating data in the order of data reference frequency, unnecessary output and calculation of the target program to access the data is unnecessary, and the translation speed of the source program is increased. be.

Furthermore, since the number of steps in the target program is reduced, the execution speed is also increased.

Furthermore, since only referenced data is allocated to the data area, there is no need to process the allocation of unnecessary data, which speeds up the translation of source programs. Since it is no longer occupied, the execution efficiency of the target program is also improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a compiler to which the recursive data allocation method according to an embodiment of the present invention is applied. FIG. FIG. 3 is a flowchart showing the processing of the reference count order data allocation in FIG. 1; FIG. Figure 1 shows an example of the arrangement of order information for the layout in Figure 1, Figure 6 shows an example of data allocation based on the system for the data allocation in the compiler of this embodiment, and Figure 7 shows an example of the conventional data allocation. The data allocation in the compiler is a diagram showing an example of data allocation based on a method. In the figure, l...compiler, 2...front end section, 3...procedure section analysis section, 4...reference number order sorting means, 5...reference number order data 811 attached means, 6... Back end part, 7... Source program, 8... Intermediate language, 9... Assignment is order information, 10... Target program, 41-45... Symbol table. Figure 1 Figure Figure Figure Figure

Claims (1)

[Claims] A computer system that accesses data by allocating base addresses as reference points at intervals of maximum displacement, setting base addresses in base registers, and setting relative addresses from the base addresses in index registers and displacements. In the compiler, a reference count sorting means obtains a pointer value to the symbol table of each data, sorts the pointer values in descending order of the number of times the data is referenced, and uses the data as allocation order information; 1. A continuous data allocation method in a compiler, comprising reference count order data allocation means for inputting allocation order information and allocating data in descending order of the number of references based on the allocation order information.