JP2000056981A - Program conversion device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] A program for converting a source program including a description of calling a DSP function consisting of a machine language instruction sequence for performing operations such as a product-sum operation and a saturation operation into an efficient machine language instruction sequence It is an object to provide a conversion device. An intermediate code generation unit converts a description in a source program to call a DSP function into an intermediate code of a function call to call a DSP function, and refers to a special operation correspondence table to perform special operation processing. The unit 103 converts the intermediate code of the function call for calling the DSP function into an intermediate code for a special operation. The intermediate code for the special operation is subjected to optimization, such as deletion of a common subexpression, by the intermediate code optimizing unit 105, similarly to the intermediate code of a general operation such as a sum or a product. Intermediate code optimization unit 105
The translation unit 106 converts the intermediate code optimized according to the above into a machine language instruction sequence and outputs it to the output file 108.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a program conversion device for converting a source program described in a high-level language into a machine language instruction sequence for a processor, and more particularly, to a function for performing a special operation such as a product-sum operation or a saturation operation. The present invention relates to a program conversion device that converts a source program including a description to be called into a conversion target.

[0002]

2. Description of the Related Art In recent years, in order to perform multimedia processing such as image processing at high speed, instructions for digital signal processing such as product-sum operation and saturation operation (hereinafter referred to as DSP instructions) have been mounted on microprocessors. ing. The software used in these microprocessors is usually
Language, object-oriented language C ++ (hereinafter simply "C ++
+ Language ”. ) Are generated by being translated into machine language instructions by a program conversion device. However, since the above-mentioned high-level language does not assume a DSP instruction, it does not have an operator indicating the DSP instruction. For this reason, conventionally, to use a DSP instruction, a function corresponding to the DSP instruction (hereinafter referred to as D
Called SP function. ) Is prepared in machine language instructions, and a description that calls the DSP function is made in a source program described in a high-level language. Note that the description to call a function can be described in a high-level language, and D is included in a source program described in a standardized high-level language.
The use of the description for calling the SP function brings benefits such as a single source program corresponding to various processors.

[0003] Hereinafter, a conventional program conversion apparatus is shown in FIG.
The operation of converting the source program shown in (1) into a machine language instruction sequence will be described. FIG. 1 is a diagram illustrating an example of a source program including a description that calls a DSP function. The source program shown in the figure is written in the C language, and “_satadd (x, y)” is a description that calls a DSP function. This DSP function is a function for performing a saturation addition operation. FIG. 12 is a functional block diagram of a conventional program conversion device. The input file 901 stores a source program including a description for calling a DSP function. Program conversion device 900
Is a so-called compiler that reads a source program stored in the input file 901, translates the source program into a machine language instruction sequence, and outputs the translated instruction to the output file 907. The intermediate code generation unit 903, the intermediate code optimization unit 904, A translation unit 905 and a DSP function expansion unit 906 are provided. The intermediate code generation unit 903 converts the source program read from the input file 901 into an intermediate code that is an internal representation used in the program conversion device. As a result of the conversion of the source program of FIG. 1 by the intermediate code generation unit 903, the intermediate code shown in FIG. 2 is generated. FIG.
FIG. 3 is a diagram showing an example of an intermediate code generated by the program conversion device corresponding to the source program shown in FIG. For example, in the intermediate code shown in FIG.
_Satadd (x, y) "," tmp cmpgt
0 ”is“ _sa ”in the source program shown in FIG.
tadd (x, y)> 0 ".

The intermediate code optimizing unit 904 performs optimization on the intermediate code generated by the intermediate code generating unit 903, such as inline expansion of functions, deletion of common sub-expressions, constant propagation, and copy propagation. However, since “_satadd (x, y)” in the intermediate code shown in FIG. 2 has the meaning of calling the DSP function, it cannot be treated as a common sub-expression even though it is included in plurals, and The conversion unit 904 does not delete the common subexpression. Here, the inline expansion of a function is to replace the place where the function is called with an intermediate code indicating the contents of the function, thereby eliminating the need for subroutine linkage and the accompanying instructions. Deletion of a common subexpression means that, when the subexpressions have equivalent values, if the evaluation is performed once, the result is stored in a variable, and the subsequent common subexpressions are replaced with the variable. It is possible to evaluate a plurality of equivalent subexpressions only once. Constant propagation means, for example, after an assignment statement of v = a for assigning a constant a to a variable v, a reference to v is replaced with a constant a until an assignment to the variable v appears, whereby the variable If is replaced by a constant, that part can be calculated at the time of translation, and the original expression can be replaced with the calculation result. In copy propagation, a constant in constant propagation is replaced with a variable. Note that "x + y" in a source program written in a high-level language
Operators and operands such as "x" and "xy" are subject to optimization such as common subexpression elimination, constant propagation, and copy propagation even after being converted to intermediate code. Translator 905
Translates the intermediate code optimized by the intermediate code optimization unit 904 into machine language instructions. This translation result is shown in FIG.

FIG. 13 shows a conventional program conversion device 90.
FIG. 10 is a diagram illustrating an example of an output of the translation unit 905 at 0. D
The SP function expansion unit 906 detects a subroutine call instruction that calls the DSP function among the machine language instructions translated by the translation unit 905, and converts this into a machine language instruction sequence stored in the machine language DSP function storage file 902. It is expanded to a certain DSP function and the result is output to the output file 907. DS
FIG. 14 shows the processing result of the P function expansion unit 906. FIG.
9 is a diagram showing an example of a processing result of a DSP function expansion unit 906 in a conventional program conversion device 900. In addition,
In the figure, the machine language instruction sequence is expressed as an assembly language program for convenience. As described above, the conventional program conversion device 900 converts a part of the source program shown in FIG. 1 into a machine language instruction sequence shown in FIG.

[0006]

In the conventional program conversion device, the DSP function is described in machine language instructions and cannot be expanded inline at the intermediate code stage. Therefore, the DSP function is not translated after the source program is translated into machine language instructions. (See FIGS. 13 and 14). For this reason, the description of calling the DSP function in the source program is not subject to optimization by the intermediate code optimization unit 904 even after the conversion into the intermediate code, so that the source program is converted into an efficient machine instruction sequence. There is a problem that you can not. Therefore, the present invention has been made in view of such problems,
It is an object of the present invention to provide a program conversion device for converting a source program including a description for calling a DSP function into an efficient machine language instruction sequence.

[0007]

In order to solve the above-mentioned problems, a program conversion apparatus according to the present invention performs optimization for applying a description including an operator and an operand of an arithmetic operation in a high-level language to a high-level language. What is claimed is: 1. A program conversion device for converting a source program described in a language into a machine language instruction sequence for a processor, and optimizing a specific function call description in the source program to call a function having a predetermined function name by passing an argument. In terms of application of, the argument is treated the same as an operand, and the specific function call description is
The source program is converted into an optimized machine language instruction sequence by treating the same as a set of an operand and an operator performing an arithmetic operation on the operand. That is, the present invention focuses on the fact that a specific function call description for calling a function consisting of a machine language instruction sequence for performing a special operation is in the form of a function call, but the content is an arithmetic operation. Since the program conversion device according to the present invention applies a specific function call description to optimization such as common subexpression elimination as well as ordinary operations such as sum and product, a source program including a specific function call description It can be converted into a machine language instruction sequence with high execution efficiency.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a program conversion device according to an embodiment of the present invention will be described with reference to the drawings. <Structure> FIG. 3 is a functional block diagram of the program conversion device 100 according to the embodiment of the present invention. FIG. 3 also shows the input file 101 and the output file 108. Here, the input file 101 stores a C-language source program including a description to call the DSP function. The output file 108 is a file in which the program conversion device 100 stores a machine language instruction sequence as a translation result of the source program stored in the input file 101. Program conversion device 10
Reference numeral 0 denotes a so-called compiler that translates (converts) a source program into a machine language instruction sequence by executing a program stored in a memory provided in a computer by a CPU. Code generation unit 102, special operation processing unit 103, special operation correspondence table 10
4. An intermediate code optimization unit 105, a translation unit 106, and a machine language conversion table 107.

Here, translating a source program into a machine language instruction sequence means generating a machine language instruction sequence for causing a processor to execute the processing content described in the source program based on the source program. . The intermediate code generation unit 102 reads a source program stored in the input file 101 into a memory, and converts the source program into an intermediate code which is an internal representation used in the program conversion device. That is, the intermediate code generation unit 102 generates an intermediate code based on the source program. Note that the intermediate code generation unit 102 is equivalent to the intermediate code generation unit 903 in the conventional program conversion device 900 described above. The special operation processing unit 103
By referring to the special operation correspondence table 104 described later,
The conversion process of the intermediate code of the DSP function call is performed. That is,
The special operation processing unit 103 detects an intermediate code for calling the DSP function from the intermediate codes generated by the intermediate code generation unit 102, and converts this to an intermediate code for a special operation. The intermediate code optimization unit 105 performs optimization such as inline expansion of a function, deletion of a common subexpression, constant propagation, copy propagation, and the like, on the intermediate code that is the processing result of the special operation processing unit 103. The translation unit 106
By referring to a later-described machine language conversion table 107, the intermediate code optimized by the intermediate code optimizing unit 105 is translated into a machine language instruction and output to the output file.

<Special Operation Correspondence Table> FIG. 4 is a diagram showing the contents of the special operation correspondence table 104. Special calculation correspondence table 104
Stores a plurality of sets of an intermediate code for calling a DSP function and a corresponding special operation intermediate code. An intermediate code for calling a DSP function such as “_satadd (x, y)” in the drawing is identical in form to an intermediate code for calling a general function. The special operation processing unit 103 determines whether the intermediate code for calling a function is an intermediate code for calling a DSP function or a general function based on whether or not the intermediate code is stored in the special operation correspondence table 104. Determine whether the code is an intermediate code. The D stored in the special operation correspondence table 104
Information about the SP function needs to be known to the source program creator. However, the recognition load on the program creator may be reduced by a source program development support tool or the like which has information on the DSP function in common. Here, when a DSP instruction is used in the source program, it is assumed that the source program has been created in accordance with a rule that a function to call a function having a function name stored in the special operation correspondence table 104 is described. An intermediate code for a special operation, such as “x sataddy” in the figure, is a new intermediate code that has not been used in the conventional program conversion device. Here, “satadd” indicates a saturation addition operation,
For example, a general intermediate code “x a
This is an intermediate code having the meaning of an operator, such as “add” in “ddy”. Also, "x satadd
"x" and "y" in "y" have the meaning of an operand for an operator. Note that “x addy” represents “x + y” in the source program as an intermediate code. “Satsub” indicates a saturation subtraction operation, and “satmul” indicates a saturation multiplication operation.

As described above, the intermediate code for special operation is
Since the intermediate code has the meaning of an operator and an operand, the meaning is referred to by the intermediate code optimization unit 105, and in terms of application of optimization, a normal operator in a high-level language is converted to an intermediate code. Is treated the same as Note that x, y, and the like in the special operation correspondence table 104 are as follows:
The variable names themselves are not specified,
It represents the argument and the second argument. Thus, the argument can be any variable name or any value. For example, according to the special operation correspondence table 104, “_satadd (y, 2)” is changed to “y satadd”.
d2 ". Also, in the optimization at the intermediate code stage, an expression consisting of an operator and an operand may be subject to common subexpression elimination,
Operands can be subject to constant propagation and copy propagation.

<Machine Language Conversion Table> FIG. 5 shows a machine language conversion table 1.
It is a figure which shows the content of 07. In the figure,
The machine language instruction is represented by a mnemonic code for convenience. The machine language conversion table 107 stores a plurality of sets of intermediate codes and one or more machine language instructions corresponding to the intermediate codes. For example, the intermediate code for special operation “saddd” is associated with the saturated addition instruction “sadd”, and the intermediate code for special operation “satsub” is associated with the saturated subtraction instruction “sssub”. Have been. Here, the machine language instruction “sadd”
And "ssub" are instructions that can be decoded and executed by the processor targeted by the program conversion device 100. In the machine language conversion table 107, information other than the correspondence between the special operation intermediate code and the machine language instruction is the same as the information used to convert the intermediate code to the machine language instruction in a general program conversion device. is there.

<Operation> The operation of the program conversion apparatus 100 having the above-described configuration will be described below by taking as an example a case where the source program shown in FIG. 1 is to be converted.
FIG. 6 is a flowchart showing the operation of the program conversion device 100. The intermediate code generation unit 102 reads a source program (see FIG. 1) stored in the input file 101 into a memory (Step S210), and generates an intermediate code in the memory based on the source program (Step S220). The generated intermediate code is as shown in FIG. The meaning of the intermediate code shown in FIG. 2 is as follows. "Tmp = _satadd (x, y)"
Is a function whose name is _sat
dd is called and the result is stored in a temporary variable t
This is an intermediate code to be assigned to mp. "Tmp cmpg
“t 0” is an intermediate code for determining whether or not the temporary variable tmp is larger than the constant 0. "Jmp_false
"Label1" is the label Label if the judgment result is false.
This is an intermediate code of a conditional branch that branches to 1. "A = _s
“attadd (x, y)” is an intermediate code that calls the function _satadd using the values of the variables x and y as arguments and substitutes the result into the variable a. "Label1"
Is an intermediate code indicating the label of the branch destination. After the intermediate code is generated by the intermediate code generation unit 102, the special operation processing unit 103 performs a conversion process of the intermediate code of the DSP function call (step S230).

Hereinafter, the conversion process of the intermediate code of the DSP function call will be described in detail with reference to FIG. 7 and FIG. FIG. 7 is a flowchart showing the conversion process of the intermediate code of the DSP function call performed by the special operation processing unit 103. The special operation processing unit 103 searches the intermediate code (see FIG. 2) generated by the intermediate code generation unit 102 for an intermediate code for a function call (step S231). If the intermediate code of the function call cannot be detected (step S23)
2), the conversion process of the DSP function call intermediate code is completed, and if the function call intermediate code can be detected (step S)
232), the special operation processing unit 103 determines whether it is an intermediate code of a DSP function call (step S23).
3). Whether the intermediate code of the function call is the intermediate code of the DSP function call (step S233) is determined by whether or not the intermediate code of the function call is the intermediate code stored in the special operation correspondence table 104. . For example,
The intermediate code “_satadd (x, y)” of the function call among the intermediate codes shown in FIG.
4 (see FIG. 4), the special operation processing unit 103 determines that the code is an intermediate code of a DSP function call. If it is determined in step S233 that the intermediate code of the function call detected in step S232 is not the intermediate code of the DSP function call, the special operation processing unit 103 proceeds to step S23.
Returning to step 1, the intermediate code generated by the intermediate code generator 102 is searched for an intermediate code for another function call. Also, as a result of the determination in step S233, DS
If it is determined that the intermediate code is a P function call intermediate code, the special operation processing unit 103 refers to the special operation correspondence table 104 to obtain a special operation intermediate code corresponding to the DSP function call intermediate code. (Refer to FIG. 4), and is generated, replaced with the intermediate code of the DSP function call (step S234), and the process returns to step S231. For example, “_satadd (x, y)” becomes “x
dd y ”.

As a result of the conversion processing of the DSP function call intermediate code by the special operation processing unit 103, the intermediate code shown in FIG. 2 is converted into the intermediate code shown in FIG. FIG. 8 is a diagram illustrating an example of the intermediate code after the conversion by the special operation processing unit 103. As shown in the figure, the special operation processing unit 103 outputs the intermediate code “tmp = _satadd (x, y)” shown in FIG.
“A = _satadd (x, y)” is “tm
p = x satadd y "," a = x satadd
y ". That is, the intermediate code of the function call having the information of calling the function _satadd by passing the argument has been replaced with the intermediate code for the special operation having the information of the operator called satadd and the operand. Hereinafter, the description returns to the flowchart based on FIG. The conversion processing of the intermediate code of the DSP function call (step S2)
The intermediate code optimizing unit 105 performs optimization on the intermediate code in the memory that has been subjected to (30) (step S2).
40). That is, the intermediate code optimization unit 105 performs optimization such as inline expansion of a function, deletion of a common subexpression, constant propagation, and copy propagation. Here, the intermediate code having the meaning of the operator such as “satadd” in the intermediate code “x satadd y” shown in FIG. 8 is to be deleted from the common subexpression, and the intermediate code optimizing unit 105 sets “a =
“x satadd y” is replaced with “a = tmp”. The intermediate code having the meaning of the operand is subject to constant propagation and copy propagation. In the process of optimization, the intermediate code for a special operation such as saturation addition, if its operand is a constant, calculates the operation using the intermediate code for the special operation, and the original special operation The intermediate code can be replaced by the calculation result.
“X satadd y” is “x +
The intermediate code “x add y” obtained by converting “y” is treated exactly the same in terms of the optimization target.

FIG. 9 shows the processing result of the intermediate code optimizing unit 105. FIG. 9 is a diagram illustrating a processing result of the intermediate code illustrated in FIG. 8 by the intermediate code optimization unit 105. After the optimization by the intermediate code optimization unit 105, the translation unit 106 converts the intermediate code into a machine language instruction sequence while referring to the machine language conversion table 107 (step S25).
0), and outputs the machine language instruction sequence to the output file 108 (step S260). For example, the special operation processing unit 103
The intermediate code “satadd” generated by the above is converted by the translating unit 106 into a saturated addition instruction “sadd”. FIG. 10 is a diagram illustrating a result of converting the intermediate code illustrated in FIG. 9 into a machine language instruction sequence by the translating unit 106. Note that the machine language instruction sequence is expressed as an assembly language program for convenience. The meanings of the machine language instructions shown in FIG. 10 are as follows. "Mov (x), R
"3" loads the value of the variable x into the register R3. "M
ov (y), R4 "loads the value of the variable y into the register R4. “Sadd R3, R4” is the register R
3 and the value of the register R4 are saturated and the result is stored in the register R4. “Cmp R4,0” compares the value of the register R4 with the constant 0. "Blt Lab1"
Is conditionally branched depending on the comparison result. "Mov R4
"(A)" stores the value of the register R4 in the variable a.
"Lab1:" is a jump destination label of a branch instruction. As described above, the program conversion device 100 converts the description of calling the DSP function in the source program into the intermediate code of the function call, and then treats the description in the same manner as the intermediate code indicating the operator in terms of optimization. It is converted into an intermediate code for a special operation instruction, and then optimized at the intermediate code stage and translated into a machine language instruction sequence.

<Consideration> The processing result of the program conversion device 100 according to the embodiment of the present invention (FIG. 10) will be described in comparison with the processing result of the conventional program conversion device 900 (FIG. 14). The precondition for both is the intermediate code shown in FIG. The program conversion device 100 reads “sad
Although one “d” is generated (see FIG. 10), the conventional program conversion device 900 generates two “sadd” (see FIG. 14). This difference is caused by the fact that the intermediate code “_satadd (x, y)” of the function call is not subject to optimization of the program conversion device 900 to delete the common sub-expression, but the program conversion device 100 does not This is due to the subject of the conversion.
The processing results of the conventional program conversion device 900 include “mov R1, R3”, “mov R2, R4”.
For saving the registers R1 and R2. This is because the conventional program conversion device 900
However, when translating “_satadd (x, y)” into a machine language instruction sequence, the registers used for the argument passing in the function call are always determined to be R1 and R2, so the registers R1 and R2 are already used. If so, a code for saving the registers R1 and R2 is generated before the function call. In contrast,
In the program conversion device 100, "_sat" shown in FIG.
add (x, y) "at the intermediate code stage to" x data
dd y ”and then translate it into machine language instructions.
Not subject to restrictions on registers associated with function calls,
The registers R3 and R4 can be used, so that no code is generated for saving the registers R1 and R2.
As described above, comparing the machine language instruction sequences shown in FIGS. 10 and 14, the machine language instruction sequence generated by the program conversion device according to the present invention is better than the machine language instruction sequence generated by the conventional program conversion device. Clearly, it is more efficient.

As described above, the program conversion device according to the present invention has been described based on the embodiments. However, it goes without saying that the present invention is not limited to these embodiments. That is, (1) In the embodiment, assuming that the instruction set of the processor targeted by the program conversion device includes a saturated addition instruction “sadd”, the “saddd” generated by the special operation processing unit 103 is assumed. Is translated by the translator 106 into a saturated addition instruction “sadd”, but the instruction set of the processor may not include a DSP instruction such as a saturation addition instruction. In this case, the machine language conversion table 107 associates a plurality of machine language instructions that realize an operation equivalent to a saturation addition instruction with an intermediate code “satadd”, and the translating unit 106 With reference to "sa
“tadd” is converted into a plurality of machine language instruction sequences.

(2) In the embodiment, the program conversion device translates the source program into a machine language instruction sequence. However, the translation into the machine language instruction sequence means translation into an equivalent assembly language program. The program conversion device may output an assembly language program. In this case, the assembly language program can be input to a so-called assembler optimizer or the like, and further converted to an optimized machine language instruction sequence.

(3) In the embodiment, the special operation processing unit 1
03 is an intermediate code having a meaning of an operator and an operand, the meaning of which is referred to by the intermediate code optimizing unit 105 and the optimization is performed. In terms of the application of, it was decided that ordinary operators in high-level languages were treated as equivalent to those converted to intermediate code. It is not limited to use. That is, if the intermediate code optimizing unit 105 determines whether or not to apply the optimization by referring to the table listing the intermediate codes as the operators, the intermediate code for the special operation is included in this table. It may be a method of adding. In addition, the intermediate code optimization unit 105 may refer to the special operation correspondence table 104 so that the intermediate code included in the special operation correspondence table 104 is handled in the same manner as the intermediate code of the operator.

(4) In the embodiment, the special operation correspondence table 1
04 is a program conversion device 1
00, but the special operation correspondence table 104
May be generated by the program conversion device 100 based on predetermined information stored in an external file. Therefore, in the embodiment, when the DSP instruction is used in the source program, the special operation correspondence table 104
It is assumed that the source program is created in accordance with the convention that the function with the function name stored in the source program is described. However, in order to use the DSP instruction in the source program, After the description that the function having the passed function name is to be called is described, information regarding the argument and the function name may be stored in a file and supplied to the program conversion device 100. In this case, the program conversion device 100 creates the special operation correspondence table 104 with reference to the supplied file.

(5) Machine language conversion table 1 in the embodiment
07, for example, the intermediate code and the machine language instruction are associated with each other such that the intermediate code for special operation "saddadd" is associated with the saturation addition instruction "sadd". Except for the correspondence between general intermediate codes and machine instructions at the same level as the conventional program converter, information on the correspondence between intermediate codes for special operations and machine instructions is stored in an external file. Alternatively, it may be generated by the program conversion device 100 based on the predetermined information. For example, by using the description in the source program to call the DSP function as a clue and referring to the file storing the machine language program module that is the main body of the DSP function,
A machine language instruction that is a conversion result of the intermediate code related to the DSP function may be specified. In addition, if the program conversion device 100 is provided with a plurality of machine language conversion tables 107 and switches between them, it can output a machine language instruction sequence corresponding to a plurality of different processors.

(6) In the embodiment, the source program in which the DSP function for performing the special operation processing is described with the same call description as the general function is the conversion target.
A source program whose function is defined as an overloaded operator in the C ++ language can be converted. This is because an overloaded operator is essentially equivalent to a function, and is primarily converted to an intermediate code for calling the function. Note that the use of the overloaded operator increases the readability of the program. Incidentally, FIG. 11 shows an example in which the source program shown in FIG. 1 is described using the overloaded operator of the C ++ language.

(7) In the embodiment, if the intermediate code has the meaning of an operator or an operand, the intermediate code optimizing unit 105 sets the intermediate code as an object of optimization such as deletion of a common subexpression. However, the same operation as the optimization at the intermediate code stage may be performed by translating the intermediate code into a machine language instruction sequence and using all information on the intermediate code.

(8) The processing procedure of the program conversion device according to the embodiment (the procedure of the flowcharts in FIGS. 6 and 7) is realized by a machine language program, and this is recorded on a recording medium and made available for distribution and sale. May be. Such a recording medium includes an IC card, an optical disk, a flexible disk, a ROM, and the like. The machine language program recorded on these is used by being installed in a general-purpose computer. That is, the general-purpose computer sequentially executes the installed machine language programs to realize the program conversion device as described in the embodiment. In addition, a computer program for causing a general-purpose computer to execute the processing procedure of the above-described program conversion device can be distributed online and distributed via a recording medium such as a hard disk, a communication line, or the like.

[0026]

As is apparent from the above description, the program conversion device according to the present invention performs optimization for a description including an operator and an operand of an arithmetic operation in a high-level language, and describes the high-level language. A program conversion device for converting the source program into a machine language instruction sequence for a processor, the method including applying an optimization to a specific function call description in the source program to call a function having a predetermined function name by passing an argument. In the aspect, by treating the argument equivalent to an operand and treating the specific function call description equivalent to a set of an operand and an operator performing an arithmetic operation on the operand, the source program is optimized. It is characterized by conversion into an instruction sequence. As a result, the description in the source program indicating that the DSP function is to be called by passing the argument is not simply a function call, but is equivalent to an optimization target such as "x + y" or an operator and an operand that can be described in a high-level language. Therefore, optimization can be performed taking advantage of the characteristic that the processing content of the DSP function is an operation. Therefore, the program conversion device according to the present invention has a DS
Compared to a conventional program conversion device that handles a description of calling a P function in the same way as a normal function call, it is possible to convert a source program including a description of calling a DSP function into a machine language instruction sequence with high execution efficiency. it can.

Here, the program conversion device converts the specific function call description into an intermediate code having characteristics to be treated as an operator and an operand of an arithmetic operation when performing optimization. General conversion means for converting a part other than the specific function call description in the source program into intermediate code, and optimization by performing optimization based on the conversion means and the intermediate code generated by the conversion by the general conversion means Optimizing means for generating the generated intermediate code, and machine language converting means for converting the intermediate code generated by the optimizing means into a machine language instruction sequence. Thereby, an intermediate code for a special operation having information meaning an operator and an operand is generated based on the description in the source program that the DSP function is to be called by passing the argument. The optimization at the intermediate code stage, which can be applied based on the above, can be applied to the intermediate code for special operation. Therefore, the program conversion device according to the present invention can convert a source program including a description for calling a DSP function into a more optimized intermediate code as compared with the conventional program conversion device. In general, when translating an intermediate code of a function call into a machine language instruction, a register used for passing arguments and a return value is predetermined. For this reason,
If the intermediate code of the DSP function call is left as it is, there will be a restriction on register allocation at the stage of translating into a machine language instruction. However, the program conversion device according to the present invention converts the intermediate code of the function call into an intermediate Since it is converted into a code, optimal register allocation can be performed without being restricted by register allocation even at the stage of translation into machine language instructions.

Further, the conversion means includes an intermediate code A including information indicating that a function having a predetermined function name is to be called by passing an argument.
And a correspondence table storage unit that stores in advance correspondence information in which an intermediate code B having a characteristic to be treated as an operator of an arithmetic operation and an operand when performing optimization is stored. A primary conversion unit for converting a description of calling a function into an intermediate code including information indicating that the function is to be called and information indicating a function name of the function to be called, and a correspondence table stored in the correspondence table storage unit Referring to the relation information, if the intermediate code generated by the conversion by the primary conversion unit is the intermediate code A including information indicating that a function having a predetermined function name is to be passed by passing an argument, the intermediate code is referred to as an intermediate code. , A secondary conversion unit for converting the intermediate code into a corresponding intermediate code B, and the optimizing means sets the intermediate code for the operator and the operand of the arithmetic operation to the optimization target. And optimizes an intermediate code having characteristics that should be treated as an arithmetic operator and an operand, as a target to which the same optimization as the intermediate code for the arithmetic operator and the operand is applied. It can also be. Thereby, the program conversion device according to the present invention stores in advance the correspondence between the intermediate code including the information indicating that the DSP function is to be called and the converted intermediate code, and refers to this to refer to the intermediate code. Since conversion is performed, if this storage content is additionally updated, various DSP function call descriptions can be handled in the same way as operations in terms of application of optimization.

Further, the function having the predetermined function name is a function whose processing content is to execute any one of digital signal processing operations including a product-sum operation and a saturation operation. The machine language conversion means can decode and execute a processing operation instruction, and the machine language conversion means can convert the intermediate code B into a digital signal processing operation instruction. Further, the optimization performed by the optimizing means may include deletion of a common sub-expression, constant propagation, or copy propagation. In this way, the program creator can easily write a program to execute a digital signal processing operation instruction such as a product-sum operation or a saturation operation in response to a processor capable of decoding and executing the operation. Even if the program is written in a high-level language in consideration of portability, portability, etc.,
You can get efficient code. That is, by describing the operation instruction for digital signal processing in the form of calling a predetermined function, optimization such as deletion of common sub-expressions, constant propagation, copy propagation, etc. is performed in the same manner as in normal operation, and efficiency is improved. It is guaranteed to be converted into a good machine language instruction sequence.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a source program including a description for calling a DSP function.

FIG. 2 is a diagram showing an example of an intermediate code generated by a program conversion device corresponding to the source program shown in FIG.

FIG. 3 is a functional block diagram of the program conversion device 100 according to the embodiment of the present invention.

FIG. 4 is a diagram showing the contents of a special operation correspondence table 104;

FIG. 5 is a diagram showing the contents of a machine language conversion table 107;

FIG. 6 is a flowchart showing an operation of the program conversion device 100.

FIG. 7 is a flowchart showing a conversion process of an intermediate code of a DSP function call performed by the special operation processing unit 103;

FIG. 8 is a diagram illustrating an example of an intermediate code after being converted by a special operation processing unit 103;

9 is a diagram illustrating a processing result of the intermediate code illustrated in FIG. 8 by the intermediate code optimization unit 105. FIG.

FIG. 10 is a diagram showing a result of converting the intermediate code shown in FIG. 9 into a machine language instruction sequence by a translating unit 106.

11 is a diagram showing an example in which the source program shown in FIG. 1 is described using a C ++ language overloaded operator.

FIG. 12 is a functional block diagram of a conventional program conversion device.

FIG. 13 is a diagram showing an example of an output of a translation unit 905 in a conventional program conversion device 900.

FIG. 14 is a diagram showing D in a conventional program conversion device 900;
FIG. 14 is a diagram illustrating an example of a processing result of an SP function expanding unit 906.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 program conversion device 101 input file 102 intermediate code generation unit 103 special operation processing unit 104 special operation correspondence table 105 intermediate code optimization unit 106 translation unit 107 machine language conversion table 108 output file 900 program conversion device 901 input file 902 machine language DSP Function storage file 903 Intermediate code generator 904 Intermediate code optimizer 905 Translator 906 DSP function expander 907 Output file

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Seiichi Urushibara 1006 Kazuma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. Terms (reference) 5B081 AA06 AA09 CC16 CC22 CC28 CC41

Claims (6)

[Claims] 1. A program conversion device for optimizing a description of an arithmetic operation operator and an operand in a high-level language as an application object and converting a source program described in the high-level language into a machine language instruction sequence for a processor. In the application of optimization for a specific function call description in the source program that calls a function of a predetermined function name by passing an argument, treat the argument in the same manner as an operand,
Converting the source program into an optimized machine language instruction sequence by treating the specific function call description as equivalent to a set of an operand and an operator performing an arithmetic operation on the operand apparatus. 2. The program conversion device, wherein the conversion unit converts the specific function call description into an intermediate code having characteristics to be treated as an operator and an operand of an arithmetic operation when performing optimization. General conversion means for converting a part other than the specific function call description in the source program into intermediate code; and optimization by performing optimization based on the intermediate code generated by the conversion by the conversion means and the general conversion means. 2. The program conversion device according to claim 1, further comprising: an optimization unit configured to generate the intermediate code, and a machine language conversion unit configured to convert the intermediate code generated by the optimization unit into a machine language instruction sequence. 3. The conversion means is treated as an intermediate code A including information indicating that a function having a predetermined function name is called by passing an argument, and an operator and an operand of an arithmetic operation in performing optimization. A correspondence table storage unit that stores in advance correspondence relation information in which an intermediate code B having a power characteristic is associated; information that calls a function in the source program; A primary conversion unit that converts the intermediate code into an intermediate code that includes information indicating the following. The intermediate code generated by the conversion by the primary conversion unit is referred to by referring to the correspondence information stored in the correspondence table storage unit. When the intermediate code A includes information indicating that a function having a predetermined function name is to be called by passing an argument, a secondary conversion unit that converts the intermediate code into an intermediate code B corresponding thereto is provided. Wherein the optimizing means applies an intermediate code for an operator and an operand of an arithmetic operation to an optimization target, and has a property to be treated as an operator and an operand of the arithmetic operation. 3. The program conversion device according to claim 2, wherein the intermediate code is optimized by applying the same optimization to the intermediate code as to the operators and operands of the arithmetic operation. 4. The function having the predetermined function name is a function whose processing content is to execute any one of digital signal processing operations including a product-sum operation and a saturation operation. 4. A processing instruction capable of decoding and executing a processing operation instruction, wherein the machine language conversion means converts the intermediate code B into an operation instruction for digital signal processing.
The program conversion device according to the above. 5. The program conversion according to claim 2, wherein the optimization performed by the optimizing means includes common sub-expression elimination, constant propagation, or copy propagation. apparatus. 6. A program conversion process for optimizing a description made up of an arithmetic operation operator and an operand in a high-level language as an object to convert a source program described in the high-level language into a machine language instruction sequence for a processor. Is a recording medium recording a control program for causing a computer to execute, wherein the program conversion process optimizes a specific function call description in the source program to call a function having a predetermined function name by passing an argument. In terms of application of, the argument is treated the same as an operand, and the specific function call description is
A recording medium for converting the source program into an optimized machine language instruction sequence by treating the same as a set of an operand and an operator performing an arithmetic operation on the operand.