JPH0619710A - Call processing method for routine in other translation unit - Google Patents

Abstract

(57) [Summary] [Objective] Regarding the processing method for calling a routine in another translation unit in the object output by the compiler 12, while shortening the processing time at the time of binding and editing, eliminating the restriction on the name of the routine in another translation unit. The purpose is to [Structure] When translating the callee object 14,
An address list 15 for storing addresses of routines called by others in the translation unit is created in an area in the translation unit. When the routine of the callee object 14 is called in the caller object 13, after setting the position of the address of the routine in the address list 15 in the branch destination indication area 16, the callee object 14 is set to the beginning of the callee object 14. Branch and call destination object
At 14, the address in the address list 15 in which the address of the routine to be called is stored is obtained from the branch destination instruction area 16, and the branch is made to the address fetched from there.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of calling a routine in another translation unit in an object output by a compiler.

When a routine in a program having different translation units is called by referring to an external name, it takes processing time to combine and edit the translation units. A technique for shortening such processing time is required.

[0003]

2. Description of the Related Art FIG. 6 is an explanatory diagram of a conventional technique. For example, as shown in FIG. 6A, when a routine in a call source program 11 having a different translation unit is called from the call source program 10, the conventional method shown in FIG.
By the process shown in (b) of, it was possible to call a routine in another translation unit.

When the calling source program 10 has a calling statement of the routine R of the called source program 11 ((a) in the figure), when the compiler is translated, the "calling statement of R" is "branched to the address of R". Convert to "instruction". That is, the "branch instruction to the address of R" is output to the object ((b) and (c) in the figure). Here, the R address is represented by a so-called V-type address constant.

When these translation results are combined and edited, as shown in (d), since the R address of the object shown in (c) is undetermined, the "R" address is changed to another translation unit ( The translation result of the call source program 11) is searched and the address of R is determined when it is confirmed.
Set in the V-type address constant area of the object shown in (c). As a result, R in the load module shown in (e) is
The actual branch destination address in the branch instruction to the address is determined.

[0006]

As described above, when calling a routine in another translation unit from the own translation unit, conventionally,
A V-type address constant is used to represent the start address of a routine in another translation unit, and the object is expanded into an instruction that branches to that address.

According to this method, the address of the routine in the other translation unit is not the self translation unit and cannot be determined unless the other translation unit is searched. Therefore, it takes a long processing time to determine the address at the time of combined editing. There was a problem.
Also, since the name of the routine in another translation unit must be treated as an external name, the name of the routine in another translation unit must be unique and there is a problem in how to name it. .

An object of the present invention is to solve the above problems, to speed up the processing at the time of combining and editing, and to eliminate the restriction on how to name routines in other translation units.

[0009]

FIG. 1 is a diagram for explaining the principle of the present invention. In the figure, 10 is a caller source program, and a translation unit in which the caller's routine exists, 1
Reference numeral 1 is a callee source program, a translation unit in which a callee routine exists, 12 is a compiler that translates the source program into an object program, 1
Reference numeral 3 is a caller object that is a translation of the caller source program 10, 14 is a callee object that is a translation of the callee source program 11, 15 is an address list in which the addresses of the callee routines are stored,
Reference numeral 16 represents a branch destination instruction area.

According to the present invention, in order to shorten the processing time for retrieving the name of the routine in the other translation unit which is the callee and fixing the address at the time of linking and editing, the caller source program 10, the callee source program 11
Is translated as follows.

When the source program 11 to be called is translated, a routine R that is called from another in the translation unit
Address list 15 for storing addresses of 1, R2, ...
In the area within the translation unit.

The calling source program 10
In the caller object 13 that has translated the above, when calling the routine of the callee object 14, an instruction for setting the position of the address of the routine in the address list 15 in a predetermined branch destination instruction area 16 , An instruction for branching to the head address of the callee object 14 or a predetermined address from the head is incorporated.

In the callee object 14, an instruction for fetching a position in the address list 15 from the branch designation area 16 at a head address or a predetermined address from the head and a branch destination address from the position in the address list 15 are fetched. And incorporate an instruction to branch to the called routine.

The processing at the time of calling is as follows, for example. In the call-source object 13, the address of the call-destination routine is set in the branch-destination designation area 16 in the address list 15. The order in which the addresses of a plurality of callee routines are arranged in the address list 15 is determined in advance at the time of design. A predetermined register, a stack area, or the like can be used as the branch destination instruction area 16.

Next, the callee object 14 branches to the head (or a predetermined address from the head). That is, whether the routine R1 or the routine R2 is called, the callee object 14 is commonly used.
Branch to the beginning of.

At the head of the callee object 14, the branch destination instruction area 16 is referenced to obtain the position in the address list 15 in which the address of the callee routine is stored.

The address of the called routine is fetched from the address list 15 based on the information obtained by the processing. Branch to the address fetched in the process.

[0018]

[Operation] By using the above call processing method, in another translation unit (in the callee object 14)
When calling this routine, it is not necessary to branch using the V-type address constant. As a result, it is no longer necessary to look up other translation units to resolve the address, nor is it necessary to treat the name of each routine as an external name.

[0019]

FIG. 2 is an example of a source program for explaining the embodiment of the present invention, FIG. 3 is an example of the structure of a callee object, FIG. The operation | movement explanatory drawing of the Example of this invention is shown.

The translation unit UNIT1 shown in FIG.
Consists of the calling program of (a) and the information of the other translation unit (UNIT2) of (b). The translation unit UNIT2 shown in (B) of FIG.
And is a collection of called routines R1, R2, ....

R1, R2, R3 in the translation unit UNIT2
If there are three routines, the result of translating them will be the structure shown in FIG. At the beginning of the callee object 14, a branch instruction to a routine to be called is prepared. In addition, each routine R1, R2
An address list 15 in which the address of R3 is stored is provided.

From the translation unit UNIT1, another translation unit U
The case of calling the routine R2 in NIT2 will be described as an example. Translation unit UNIT1 and translation unit UN
The processing and operation in IT2 are as shown in FIGS. 4 and 5.

The displacement “4” from the beginning of the address list 15 in which the address of the routine R2 is stored is set in the branch destination designation area 16 (hereinafter referred to as area X).
The area X is an area that can be referred to from both UNIT1 and UNIT2.

Branch to the beginning of UNIT2. At the beginning of UNIT2, first refer to area X,
The displacement "4" in the address list 15 in which the address of the routine R2 is stored is obtained. And address list 15
The value "address of R2" stored in the (first + 4 bytes) of is extracted.

It branches to the address of R2 taken out in the process. Similarly, if the value set in the area X in the above processing is "0", the routine R1 is called, and if it is "8", the routine R3 is called.

[0026]

As described above, according to the present invention,
Since it is not necessary to search for another translation unit to perform address resolution at the time of binding and editing, processing time is shortened, and there is no restriction on the name of a routine called from outside.

[Brief description of drawings]

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

FIG. 2 is a diagram showing an example of a source program for explaining an embodiment of the present invention.

FIG. 3 is a diagram showing an example of a structure of a callee object according to the embodiment of the present invention.

FIG. 4 is an explanatory diagram of a calling process according to the embodiment of the present invention.

FIG. 5 is an operation explanatory diagram of the embodiment of the present invention.

FIG. 6 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 10 Caller Source Program 11 Callee Source Program 12 Compiler 13 Caller Object 14 Callee Object 15 Address List 16 Branch Destination Instruction Area

Claims (1)

[Claims] 1. A method for processing a call of a routine in another translation unit in an object output by a compiler (12), storing an address of a routine called from another in the translation unit at the time of translation of a callee translation unit (14). The address list (15) to be created is created in the area within the translation unit, and the caller translation unit (13) is called in the callee translation unit.
When calling the routine of (14), after setting the position of the address of the routine in the address list (15) in a predetermined area (16), the called translation unit (14)
Address list that stores the address of the routine called from the predetermined area (16) in the callee translation unit (14) by branching to the first address or a predetermined address from the beginning
(15) A method of calling a routine in another translation unit, characterized in that the position in (15) is obtained and the address is branched to the address fetched from it.