JPH1031591A - In-line developing device for function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop in-line of functions in differrent compiling units. SOLUTION: A function calling and finding means 1 judges whether a function calling exists in plural object programs or not and when the function calling exists, creates a function calling information table 6. A function definition finding means 2 searches a function definition of a function calling stored in the function calling information table 6, creates a function definition table and copies the size of an applicable function and an object of the function. A prologue and epilogue removal means 3 removes the prologue and the epilogue unnecessitated by the in-line development for the object of the function stored in the function definition table. A function in-line development means 4 refers to a function calling table for the function stored in the function definition table and deletes a function calling instruction by embedding the object stored in the function table in a spot of function calling.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inline expansion device for a function called in a program.

[0002]

2. Description of the Related Art Generally, in a procedure for creating a program in a high-level language, a function is created for each function and a file is divided. Many of the functions created for each function are in small units, such as the passing of arguments in the function call part, the setting of return addresses, the processing of return values, the function calls (hereinafter referred to as call strings), and the calls. Processing such as allocating a dynamic stack at the beginning of a function that has been saved, saving registers that need to be saved, saving return addresses, etc.
Prologue processing) and release of the dynamic stack at the end of the called function, restoration of saved registers,
The generated code is generated because it is a function call such as a process of setting a return value and returning to a return address (hereinafter, referred to as an epilogue process), and the smaller the function body, the larger the overhead ratio.

Conventionally, to eliminate this overhead,
When the compiler compiles the source, if there is a function call in the source program unit and the definition of the function exists in the same source program unit, the code of the calling sequence is generated at the function call location and the function is generated. Rather than calling the function, instead of calling the function, a process of embedding the body code of the function excluding the prologue processing and epilogue processing (hereinafter referred to as inline expansion) is performed. The execution sequence of the execution program is improved by deleting codes that are not related to the main body of the function, such as a call sequence of the function, a prologue process of the called function, and an epilogue process.

[0004]

In the above-described conventional function inline expansion method, even if a function that is frequently called exists, the compiler compiles the source program unit, so that the source program that calls the function and the If the source program having the function definition is different, there is a problem that the function code cannot be resolved at the time of compiling the source program calling the function, and the function inline expansion cannot be performed.

[0005] The present invention has been made in view of the above points, and in order to improve the execution speed of an execution program, instead of performing inline expansion of a function at compile time,
An object of the present invention is to provide a function inline expansion device that embeds a function definition object in a portion where each function is called by a linker at the time of linking an object program, and performs function inline expansion.

[0006]

The function inline expansion apparatus of the present invention performs inline expansion of a function called by a program at the time of linking to create an execution program by combining object files of the program. And

More specifically, the function inline expansion device according to the present invention reads an object program and creates an execution program in a linking process.
When a function call exists in a plurality of object programs, the function name of the calling function and the call position of the function are used as constituent elements, and the function call information table created for each function call and the function call information table are searched. Determines whether a function is a terminal function, and if it is a terminal function, creates a function definition table with the function size and function object as constituent elements and a function call table in the object program, and creates a function call table Function definition finding means for searching function definitions of function calls stored in a function call information table, determining whether the function is a terminal function, and creating a function definition table; Function objects stored in tables are no longer required by inline expansion A prologue / epilogue removal means for removing a function prologue and epilogue instruction, and for a function stored in a function definition table, referencing a function call table, embedding an object stored in the function table at a function call location, The function inline expansion means for deleting the function call instruction, and the reference address changing means for correcting the relative address of the jump instruction and the jump instruction destination in the parent function object of the inline function by the function inline expansion means.

[0008]

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 function inline expansion apparatus using a linker according to the present invention. The function call discovery table 6 for inputting an object program (not shown) and creating a function call information table 6 is shown. Means 1, function definition finding means 2 for creating a function definition table 7 with reference to the function call information table 6, and prologue / epilogue removal means 3 for deleting the prologue and epilogue of the function object in the function definition table 7; A function inline expansion unit 4 for performing function inlining by referring to the function definition table 7 and the function call information table 6, and a reference address changing unit 5 for correcting the relative address of the label reference of the object after the inline expansion. I have.

The function inline expansion apparatus using the linker of the present invention optimizes the execution speed by performing the following processing prior to the ordinary linker link processing.

First, the function call finding means 1 is an entry having information such as a function call position, an index into a symbol table, and a relocation type among the entries in the data portion of all object programs (hereinafter referred to as a relocation entry and a relocation entry). In addition, the object program searches for a symbol table having information such as the symbol name, the start address of the function, and the end address of the function indicated by the relocation entry. As a result of these searches, a function call information table 6 is generated from the detected relocation entry and the symbol table.

As shown in FIG. 2, the function call information table 6 includes the function name of the call function and the call position of the function of the call function as constituent elements. The function call position obtained from the relocation entry of the data section of the above is set in the function call information table 6. The function name obtained from the symbol table detected by the function calling means 1 is stored in the function calling table 6.
And the function call information table 6 is generated.

Next, the function definition finding means 2 selects a symbol table in which a start address and an end address of the function are set from a plurality of symbol tables created for each function call and function definition. Then, a symbol table corresponding to the function name in the function call information table 6 created by the function call finding means 1 is selected from the symbol tables in which the start address and the end address of the function are set. Here, for the symbol table created by the function call, when the compiler creates the symbol table, the start address of the function and the end address of the function cannot be resolved, so the start address of the function and the end address of the function are set. I haven't. The function definition finding means 2 acquires the size of the function from the start address of the function and the end address of the function in the selected symbol table, and sets the size in the function definition table 7.

The function definition finding means 2 sets objects from the start address of the function of the detected symbol table in the object of the object program to the end address of the function in the function definition table 7. Further, all instructions of the function object are checked to determine whether there is another function call instruction. If there is no function call instruction, it is determined that the function has no function call (hereinafter referred to as a terminal function), and the function definition table 7 is generated.

As shown in FIG. 3, the function definition table 7 is composed of a function size and a function object as constituent elements. The function size of the function detected by the function definition finding means 2 and the function definition Is copied, and the function definition table 7 is generated.

Next, the prologue / epilogue removal means 3
Is the function definition table 7 created by the function definition finding means 2.
For each function object, the prologue processing instruction, which becomes unnecessary by inlining the function,
Remove epilogue processing instructions.

Next, the function inline expansion means 4 uses the prologue / epilogue removal means 3 to replace the object of each function in the function definition table 7 from which the prologue / epilogue instruction has been removed with the function call position in the function call information table 6. Reference and embed at the call location. After embedding the object at the calling position, the instructions in the calling sequence such as the calling instruction of the corresponding function are removed.

Finally, the reference address change processing 5 includes a function (hereinafter, referred to as a parent function) which calls a corresponding function (hereinafter, referred to as an inline function) subjected to inline expansion by the function inline means 4. If there is a jump instruction that straddles the instruction, the relative address between the jump instruction and the jump destination instruction is calculated and corrected because the inline expansion of the inline function changes the relative address between the jump instruction and the jump destination instruction. Also, the size of the parent function is recalculated, and the end address of the function in the parent function symbol table is updated.

Although the above embodiment is directed to a case where the inline function is a terminal function, the present invention is not limited to this, and can be applied to a case where the inline function is not a terminal function. That is, according to the present invention, the function call finding means 1, the function definition finding means 2, the prologue / epilog removing means 3, the function inline expanding means 4 and the reference address changing means 5 in the above embodiment are repeated until there is no function call. It can be realized by functioning.

[0020]

As described above, the present invention optimizes the execution speed by inline expansion of functions by a linker. Even if there is a calling relationship of a different function in a unit of a source program, the function of the function can be inlined. Since the expansion can be performed, there is an effect that the overhead due to the function call can be reduced and the execution speed of the execution program can be improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of the present invention.

FIG. 2 is a configuration diagram of a function call information table which is a component of the present invention.

FIG. 3 is a configuration diagram of a function definition table that is a component of the present invention.

[Explanation of symbols]

 1 function call finding means 2 function definition finding means 3 prologue / epilogue removal means 4 function inline expansion means 5 reference address changing means 6 function call information table 7 function definition table

Claims (3)

[Claims] 1. A function inline expansion apparatus for performing inline expansion of a function called by a program at the time of linking to create an execution program by combining object files of the program. 2. A function call information table created for each function call, including a function name of a call function and a call position of the function when the function call exists in a plurality of object programs. A function definition table having a function size and a function object detected from a call information table as constituent elements, a function call discovery means for searching for a function call in an object program and creating the function call table, and the function call A function definition finding means for searching for a function definition of a function call stored in the information table and creating the function definition table, and unnecessary for the object of the function stored in the function definition table by inline expansion. Prologue to remove function prologue and epilogue instructions - and epilogue removal means, the functions stored in the function definition table,
Function inline expansion means for referring to a function call table, embedding an object stored in the function table at a function call location, and deleting a function call instruction; jumping in the parent function object of the inline function by the function inline expansion means 2. The function inline expansion apparatus according to claim 1, further comprising: a reference address changing unit for correcting a relative address of an instruction and a jump instruction destination. 3. The function definition finding unit according to claim 2, wherein the function definition finding unit determines whether the function retrieved from the function call information table is a terminal function, and creates the function definition table. Inline expansion device.