JP2010026968A - Circuit generation support program and circuit generation support method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To generate a source code suitable to be mounted on target hardware on the basis of a source code described in a software language, such as C language. <P>SOLUTION: A second source code (104) for a target for mounting on the target hardware is generated on the basis of a first source code (103) by executing by a computer system each of the following processes: for sequentially retrieving circuit types which are achieved by an action algorithm with reference to the first source code (103) that describes the action algorithm of an electronic circuit in a software language; for selecting candidates corresponding to descriptions by retrieved circuit are from a description library (102); for replacing the descriptions by circuit type of the first source code with a description following the specifications of the target hardware on the basis of the selected candidates to make the second source code for the target (104). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a program and a conversion method for converting source code into source code suitable for mounting on target hardware, for example, an automation technique effective when applied to a development environment of a semiconductor integrated circuit (LSI).

  Patent Document 1 discloses a method of inputting a signal processing source code (hereinafter referred to as a signal processing C source code) in which an operation algorithm of an electronic circuit is described in a high-level language such as C language and outputting a hardware description language. Is done. This analyzes the syntax of the input source code description, performs resource binding and scheduling, and outputs an RTL circuit diagram.

  Patent Document 2 describes a technique for optimizing an algorithm description written in C language for hardware design. That is, an algorithm C description 1 in which an arithmetic operation or control algorithm of a logic circuit is described in C language is divided into a plurality of states in a processing unit in a function C conversion system, and the execution order of the divided processing is described as a state transition. Thus, the function C description 2 in which the control description is embedded is generated. In the RT level C conversion system, a clock description which is a concept of time is inserted into the function C description 2 and converted into the RT level C description 3. The RT level C description 3 is converted into an HDL RT level description by an existing conversion tool.

Japanese Patent Laid-Open No. 2005-78402 JP 2003-16122 A

  The signal processing C source code created for the purpose of executing on a computer tends to secure a buffer memory used for calculation with a large capacity and to have a complicated loop structure. In Patent Documents 1 and 2, when the signal processing C source code described above is input as it is, it is expected that there will be a shortage of memory and circuit element resources on the target hardware, and this is not taken into consideration.

  An object of the present invention is to provide a technique for generating a source code suitable for mounting on target hardware based on a source code described in a software language such as C language.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  The following is a brief description of an outline of typical inventions disclosed in the present application.

  That is, referring to the first source code in which the operation algorithm of the electronic circuit is described in the software language, the circuit types realized by the operation algorithm are sequentially searched, and the candidate corresponding to the description of the searched circuit type is selected and selected. The description of the circuit type is replaced with a description conforming to the specifications of the target hardware based on the candidates, and each process of outputting the second source code for the target for which the replacement has been completed is executed by the computer device The second source code for the target for implementation on the target hardware is generated based on the first source code.

  The effects obtained by the representative ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, it is possible to generate source code suitable for mounting on target hardware based on source code described in a software language such as C language.

1. First, an outline of a typical embodiment of the invention disclosed in the present application will be described. Reference numerals in the drawings referred to in parentheses in the outline description of the representative embodiments merely exemplify what are included in the concept of the components to which the reference numerals are attached.

  [1] A circuit generation support program (100) according to the present invention includes a first process (401) for inputting a first source code (103) describing an operation algorithm of an electronic circuit in a software language, and an input first source. A second process (402 to 405) for sequentially searching for circuit types realized by the operation algorithm with reference to the code, and a third process (507, 508) for selecting a candidate corresponding to the description of the searched circuit type, Based on the candidate selected in the third process, the description of the circuit type of the first source code is replaced with a description conforming to the specifications of the target hardware to obtain the second source code (104) for the target. The target for mounting from the first source code to the target hardware by executing the processing (509) on the computer device Obtaining a second source code.

  Generally, conversion from signal processing C source code as the first source code to hardware C source code as the second source code requires know-how and advanced techniques, and the development man-hour tends to increase. It is known that there is. According to the above means, it is possible to convert a circuit portion realized by an arbitrary operation algorithm into a description that is tuned according to hardware specifications such as a configuration of a computing unit and a memory capacity, and development of a circuit or a system. It can contribute to shortening of man-hours.

  [2] In the circuit generation support program according to item 1, the software language is a C language.

  [3] In the circuit configuration generation assistance program according to item 1, in the third process, the candidate is selected from the description library (102). Since candidates are selected from the library, it is also possible to prepare a library having a track record of operation as a library, thereby increasing the reliability of the circuit or system developed using the second source code. It becomes easy. For example, reduce the number of accesses to devices that have a proven record of specification constraints such as short processing execution cycles and small memory capacity for computation, or devices that are slow to read or write data. The description for this is stored in the library as a basic set.

  [4] The circuit generation support program according to item 3 further includes the description library. This saves you the trouble of building a description library later.

  [5] In the circuit generation support program according to item 3, the second process includes a search process (402) for searching for a circuit type code embedded in advance as a circuit type in the first source code, and a searched circuit type. And storage processing (404, 405) for storing information for specifying the code and its description position. In the fourth process, the circuit type code is commented, and a description corresponding to the specification of the target hardware is inserted after the comment. The circuit type code is, for example, a function tag, header, or label.

  [6] In the circuit generation support program according to item 5, the fourth process displays (504) an input window for parameters to be given to one candidate selected from the description library, and there is a parameter specified in the input window. In some cases, a description is generated and replaced (505 to 509). Flexibility for conversion contents can be increased.

  [7] The circuit generation support method according to the present invention refers to the first process (401) for inputting the first source code (103) describing the operation algorithm of the electronic circuit in software language, and the input first source code Then, a second process (402 to 405) for sequentially searching circuit types realized by the operation algorithm, a third process (507, 508) for selecting candidates corresponding to the description of the searched circuit type, A fourth process (509) that replaces the description of the circuit type of the first source code with a description conforming to the specifications of the target hardware based on the candidates selected in the three processes to obtain the second source code for the target. In addition, the first source code is converted into the second source code for the target for implementation on the target hardware using a computer device.

  According to the above means, a circuit part realized by an arbitrary operation algorithm can be converted into a description that is tuned according to restrictions on hardware specifications such as the configuration of a computing unit and memory capacity.

  [8] In the circuit generation support method according to item 7, the software language is a C language.

  [9] In the circuit generation support method according to item 7, the candidate is selected from the description library (102) in the third process.

  [10] In the circuit generation support method according to [9], the second process includes a search process (402) for searching for a circuit type code embedded in advance as a circuit type in the first source code, and a searched circuit type And storage processing (405, 404) for storing the code and information for specifying the description position. In the fourth process, the circuit type code is commented, and a description corresponding to the specification of the target hardware is inserted after the comment.

  [11] In the circuit generation support method according to item 10, the fourth process displays an input window for parameters to be given to one candidate selected from the description library (504), and there is a parameter specified in the input window. In some cases, a description is generated and replaced (505 to 509).

2. Details of Embodiments Embodiments will be further described in detail. DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments for carrying out the invention, and the repetitive description thereof will be omitted.

  FIG. 1 schematically shows the configuration of a circuit generation support program according to the present invention and the relationship between the circuit generation support program and the source code of a circuit to be designed. The circuit design generation program constitutes a part of a development environment for developing a circuit or system such as a semiconductor integrated circuit, and is executed by a computer apparatus such as a PC (personal computer) or an EWS (engineering workstation). It is a program.

  When this circuit generation support program 100 is executed by a computer device, the signal processing C source code 103 as the first source code in which the operation algorithm of the electronic circuit is described in a software language is mounted on the target hardware. The processing for converting into the hardware C source code 104 as the second source code for the target is controlled. Target hardware means a circuit or system to be developed. The circuit generation support program 100 includes a hardware C model generation unit 101 for defining a processing procedure for performing the conversion, and a signal processing library 102.

  A hardware C model generation unit 101 receives a signal processing C source code 103, refers to the input signal processing C source code 103, and implements a circuit realized by an operation algorithm described in the signal processing C source code 103 The type is sequentially searched, a candidate corresponding to the description of the searched circuit type is selected from the signal processing library 102, and is replaced with a description according to the specification of the target hardware of the circuit type based on the selected candidate. A series of processes for outputting the hardware C source code 104 that has been completed is controlled. The signal processing library 102 stores, for example, a plurality of types of hardware C source code forms in units of functions. The C source code form for hardware is selected as the selectable candidate.

  Before describing the specific processing procedure of the circuit generation support program 100, the computer apparatus which is the operating environment of the program will be described. FIG. 2 illustrates a computer device that executes the circuit generation support program 100.

  The computer device 200 that executes the circuit generation support program 100 includes, for example, a CPU 201 as a central processing unit, a RAM (Random Access Memory) used as a work area for storing an execution program, data to be calculated, and the like. ) And an auxiliary storage device 203 as a file storage for storing an execution program and an input / output file used by the execution program, and these are commonly connected to the bus 215. A monitor 209, a keyboard 210, and a mouse 211 are connected to the bus 215 as input / output devices for the user to operate the computer device 200. Further, a recording medium reading / writing device 207 and a network controller 208 are connected to the bus 215. The recording medium read / write device 207 performs read and write access control for computer-readable recording media 212, 213, and 214 such as a CD-ROM. The network controller 208 controls a communication protocol for downloading and uploading data and programs to a network (not shown).

  The circuit generation support program 100 and the signal processing C source code are not particularly limited, but the circuit generation program 100 and the signal processing C source code 103 provided by the recording media 212 and 213 and read from the recording media 212 and 213 are auxiliary storage. Once stored in the device 203.

  When executing the circuit generation support program 100, first, the CPU 201 loads the circuit generation support program 100 from the auxiliary storage device 203 to the memory 202, and the CPU 210 fetches and executes the loaded circuit generation support program 100 by memory access. . The circuit generation support program 100 creates a circuit generation information file 204 as intermediate data for execution control, and the circuit generation information file 204 and the generated hardware C source code 104 are temporarily stored in the auxiliary storage device 203. It is sufficient to temporarily store the circuit generation information file 204 and the generated hardware C source code 104 in the auxiliary storage device 203 when the work area of the memory 202 is insufficient. The signal processing C source code 103 may be prepared by editing by the operator on the computer device 200, or may be downloaded from the recording medium 213 via the recording medium read / write device 207 or the network controller 208 may be installed. You may download from a network and prepare. The hardware C source code 104 output from the circuit generation support program 100 is temporarily held in the auxiliary storage device 203 and written to the recording medium 214 via the recording medium read / write device 207 or specified via the network controller 208. You may upload to other communication partners.

  FIG. 3 illustrates the highest level processing flow of the circuit generation support program. When the circuit generation support program 100 is started (300), an input / output file selection window for selecting an input / output destination of the circuit generation information file 204, the signal processing C source code 103, and the hardware C source code 104 is displayed. It is displayed (301). In the input / output file selection window, first, the input source of the signal processing C source code 103 is selected by a file name or the like (302), the output destination of the circuit generation information file 204 is selected by a file name or the like (303), and the hardware A process (304) of selecting an output destination of the wearable C source code 104 by a file name or the like is performed. Next, in response to a search instruction by operating a circuit type search button (illustrated in FIG. 8) or the like, the signal processing C source code 103 is referred to, and the operation algorithm described in the signal processing C source code 103 is implemented. The circuit types to be searched are sequentially searched (305). Further, in response to a start instruction by an operation of a circuit generation execution button (shown in FIG. 8) or the like, from the description of the retrieved circuit type using a candidate selected from the signal processing library according to the description of the retrieved circuit type. A process for generating a description according to the specifications of the target hardware is executed (306). After completion of the generation process, it is determined whether the same process is continuously performed for another signal processing C source code 103 (307). When continuing, it returns to the process step 302. If not continued, the execution of the circuit generation support program 100 is terminated (308).

  FIG. 4 illustrates a detailed processing flow of the circuit type search (step 305 in FIG. 3). Here, a case where the circuit type code is embedded in the signal processing C source code is taken as an example.

  First, the counter CNT for counting the number of descriptions in which the circuit type is described is initialized to zero (400), and the signal processing C source code 205 to be processed is read (401). A circuit type code is retrieved from the signal processing C source code 205 (402). The presence / absence of the circuit type code is determined (403). If it appears, the circuit type code and the position of the circuit type code appear in the circuit generation information file 204 (404), and 1 is added to the counter CNT. The process returns to process step 402 (405). Steps 402 to 405 are repeated until the circuit type code no longer appears. When the circuit type code no longer appears, the counter CNT is recorded in the circuit generation information file 204 and the process returns to the upper flow of FIG. 3 (406). .

  FIG. 5 shows a detailed processing flow of the circuit description generation process (step 306 in FIG. 3). The value of the counter CNT indicating the number of descriptions of the circuit type is read from the circuit generation information file 204 (500). Here, if the value of the counter CNT is zero, it indicates that there is no target circuit to be converted, so the processing is immediately terminated (501). When the value of the counter CNT is larger than zero, the circuit type code and the generation circuit insertion position are read from the circuit generation information file 204 (502, 503). Next, a circuit parameter input window corresponding to the circuit type code is displayed (504). In the circuit parameter input window, parameters necessary for generating the circuit description are input (505). Immediately after the window is displayed, a predetermined initial value is displayed in the circuit parameter input field. If there is no correction, the initial value is set as the circuit parameter (505). Processing step 505 is performed until all necessary circuit parameters have been input (506). When input of all circuit parameters is completed, a source code form as a candidate corresponding to the circuit type code is read from the signal processing library 102 (507), and the input circuit parameters are given to the source code form. As a result, a hardware C source code for the circuit portion corresponding to the circuit type code is generated (508). The generated C source code is inserted into the position of the corresponding circuit type code in the signal processing C source code 205, 1 is subtracted from the value of the counter CNT, and the process returns to the processing step 501. Thereafter, the processing steps 501 to 510 are repeated until the value of the counter CNT becomes zero.

  FIG. 6 illustrates the configuration of the circuit type code table. It should be understood that the circuit type code table 600 is configured by being incorporated in a part of the circuit generation support program 100, and is, for example, a part of the hardware C model generation unit 101. The circuit type code table 600 includes two types of information: a circuit type code assigned to each functional unit and a reference address of a source code form prepared for expressing the circuit as a hardware C source code. Source code forms are registered together in the signal processing library 102. For example, in FIG. 6, the circuit type code “HFIL” of the horizontal filter for image processing is assigned as the circuit type code 1 (601), and the reference destination 1 (602) is the horizontal filter source code form of the signal processing library 102. The storage address is recorded. The circuit type code “VFIL” of the image processing vertical filter is assigned as the circuit type code 2 (603), and the storage address of the vertical filter source code form of the signal processing library 102 is recorded in the reference destination 2 (604). Yes. If the circuit type code table is not provided, the storage address of the source code form may be individually specified directly by the program description in the hardware C model generation unit 101.

  FIG. 7 illustrates the configuration of the circuit generation information file. The circuit generation information file 204 includes a counter CNT indicating the number of circuit type descriptions, a path type code of the circuit to be generated, and a circuit type code description position on the signal processing C source code (that is, the generated hardware C source code). Information indicating the insertion position). There are as many circuit type codes as the number (701) of the counter CNT of the number of descriptions of the circuit type. In FIG. 7, the first circuit type code 1 (702) is “HFIL”, which indicates that a horizontal filter for image processing is generated. The description position 1 (702) stores a position describing “HFIL” on the signal processing C source code 103. The second circuit type code 2 (703) is “VFIL”, which indicates that an image processing vertical filter is generated. The description position 2 (704) stores a position describing “VFIL” on the signal processing C source code 13.

  FIG. 8 illustrates an input / output file selection window. In the input / output file selection window 800, operations for selecting an input / output file used by the circuit generation support program, selecting a type of circuit to be generated, and executing circuit generation are performed. The file name of the signal processing C source code 103 is designated by an operation of a button 801. The output file name of the circuit generation information file 204 is designated by operating the button 802. The file name of the hardware C source code 104 is designated by an operation of a button 803. The search for the circuit type in the file of the signal processing C source code 103 is started by operating the button 805. The circuit generation process is started by operating the button 806. The signal processing C source code 103 and the hardware C source code 104 are displayed in a text window 804.

  FIG. 9 illustrates a circuit parameter input window. The example in the figure shows an example of the circuit parameter input window of the horizontal filter for image processing. The circuit ID is a name arbitrarily designated by the user. This is used to distinguish the horizontal filter to be created from other horizontal filter circuits. The filter tap unit is the number of filter coefficients constituting the horizontal filter. The filter coefficient is a numerical value expressing the frequency characteristic of the filter. The bit shift amount is a correction amount of the range of the calculation result after the horizontal filter calculation. The horizontal image size is the number of pixels in the horizontal direction of the calculation target image. The vertical image size is the number of pixels in the vertical direction of the calculation target image. Each parameter can be input in an input field indicated by reference numerals 901 to 906. The initial values are displayed in the input fields 901 to 906 and can be rewritten to desired values. Reference numeral 907 denotes a button for instructing completion of parameter input.

  FIG. 10 shows an example of a circuit type code described in the signal processing C source code. When a circuit type code is described in the signal processing C source code 103, there is a description for converting into the C source code for hardware at an arbitrary location (for example, near the top of the source code) of the source code. For example, a declaration statement indicating that the process can be executed is described. In the example of the figure, “#define HARDWARE” (1001) is described. The “HARDWARE” part may be arbitrary. “#Ifdef HARDWARE” and “#endif” are described in the portion 1003 where the circuit is to be inserted, and the circuit type code 1004 of the circuit to be inserted is described therebetween. For example, in the case of a horizontal filter, “CTYPE = HVFIL” is described. “CTYPE =” on the left side indicates that the description code on the right side is a circuit type code. Reference numeral 1002 denotes a portion of the signal processing C source code that is not subject to replacement by the circuit type code.

  FIG. 11 shows an output example of the hardware C source code 104. The hardware C source code generated corresponding to the circuit type code is inserted at the place where the circuit type code is written in the signal processing C source code. In the figure, an example is shown in which a horizontal filter hardware C source code 1105 is inserted after a location 1003 where a circuit type code “CTYPE = HVFIL” is described. The hardware C source code may be described in the form of a function with several arguments. In this case, only the function call instruction can be described after the circuit type code “CTYPE = HVFIL”, and the function body can be arranged at another arbitrary position. The description part of “CTYPE = HVFIL” is commented out as “/ * CTYPE = HFIL * /” (1104), which also means the completion of circuit generation.

  The hardware C source code generated by executing the circuit generation support program on a computer device is input to a logic synthesis tool and used to generate a circuit diagram, or input to a simulator and used for simulation, etc. Used for

  In general, know-how and advanced techniques are required to generate C source code optimized for implementation on target hardware, and it is known that development man-hours tend to increase. By using the circuit generation support program, it is possible to generate a description in which a circuit portion realized by an arbitrary operation algorithm is tuned according to hardware specifications such as a configuration of a computing unit and a memory capacity. This can contribute to shortening the system development man-hours. In particular, since candidates are selected from the library, it is also possible to prepare a library having an operation record as a library, whereby the operation of the circuit or system developed by the C source code generated using this program It is also easy to improve the reliability of the surface. For example, reduce the number of accesses to devices that have a proven record of specification constraints such as short processing execution cycles and small memory capacity for computation, or devices that are slow to read or write data. If such a description is stored in the library as a basic set, such design assets can be easily used only by specifying a circuit type code.

  Although the invention made by the present inventor has been specifically described based on the embodiments, it is needless to say that the present invention is not limited thereto and can be variously modified without departing from the gist thereof.

  For example, the function of the signal processing library used in the circuit generation support program and the circuit generation method according to the present invention includes, for example, a scaling filter, an image quality conversion filter, and a predetermined method encoding and decoding used for improving the image quality of moving images. Naturally, circuit functions for realizing various data processing, data transfer processing, and the like as well as discrete cosine transform, motion estimation, motion compensation, and the like used in the conversion may be included. The present invention can be applied to various semiconductor integrated circuit development environments as a technique for converting a signal processing program written in a C program into a hardware C program.

FIG. 1 is an explanatory diagram schematically illustrating the configuration of a circuit generation support program according to the present invention and the relationship between the circuit generation support program and the source code of a circuit to be designed. FIG. 2 is a block diagram of a computer device that executes the circuit generation support program. FIG. 3 is a flowchart illustrating the highest level processing of the circuit generation support program. FIG. 4 is a flowchart illustrating details of the circuit type search (step 305 in FIG. 3) process. FIG. 5 is a flowchart illustrating details of the circuit description generation process (step 306 in FIG. 3). FIG. 6 is an explanatory diagram illustrating the configuration of the circuit type code table. FIG. 7 is an explanatory diagram illustrating the configuration of a circuit generation information file. FIG. 8 is an explanatory diagram illustrating the configuration of the input / output file selection window. FIG. 9 is an explanatory diagram illustrating the configuration of the circuit parameter input window. FIG. 10 is an explanatory diagram illustrating a circuit type code described in the signal processing C source code. FIG. 11 is an explanatory diagram illustrating an example of an output form of hardware C source code.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Circuit generation support program 101 ... C model production | generation part for hardware 102 ... Signal processing library 103 ... Signal processing C source code 104 ... C source code for hardware 200 ... Computer apparatus 201 ... CPU
202 ... Memory 203 ... Auxiliary storage device 600, 603, 1004 ... Circuit type code 1104 ... Commented circuit type code 1105 ... Hardware C source code inserted corresponding to circuit type code 900 ... Parameter input window

Claims (11)

A process for generating a second source code for a target for implementation on the target hardware based on the first source code in which the operation algorithm of the electronic circuit is described in a software language by being executed by the computer device A circuit generation support program for controlling,
The process for generating includes a first process for inputting a first source code, a second process for sequentially searching circuit types realized by an operation algorithm with reference to the input first source code, and a search A third process for selecting a candidate corresponding to the description of the circuit type, and a description of the circuit type of the first source code is replaced with a description according to the specifications of the target hardware based on the candidate selected in the third process A circuit generation support program, comprising: a fourth process using the second source code.   The circuit generation support program according to claim 1, wherein the software language is a C language.   The circuit generation support program according to claim 1, wherein in the third process, the candidate is selected from a description library.   The circuit generation support program according to claim 3, further comprising the description library. The second process includes a search process for searching for a circuit type code embedded in advance as a circuit type in the first source code, and an accumulation for storing information for specifying the searched circuit type code and its description position. Processing,
4. The circuit generation support program according to claim 3, wherein, in the fourth process, the circuit type code is commented, and a description corresponding to the specification of the target hardware is inserted after the comment.   6. The fourth process displays an input window for parameters to be given to one candidate selected from the description library, and when there is a parameter specified in the input window, generates a description according to the parameter and replaces it. The circuit generation support program described. A circuit generation support method for generating a second source code for a target for mounting on a target hardware based on a first source code in which an operation algorithm of an electronic circuit is described in a software language using a computer device ,
A first process of inputting a first source code;
A second process for referring to the input first source code and sequentially searching for circuit types realized by the operation algorithm;
A third process for selecting a candidate corresponding to the description of the retrieved circuit type;
A circuit including: a fourth process in which the description of the circuit type of the first source code is replaced with a description conforming to the specification of the target hardware based on the candidate selected in the third process to obtain the second source code. Design support method.   The circuit generation support method according to claim 7, wherein the software language is a C language.   The circuit generation support method according to claim 7, wherein the candidate is selected from a description library in the third process. The second process includes a search process for searching for a circuit type code embedded in advance as a circuit type in the first source code, and an accumulation for storing information for specifying the searched circuit type code and its description position. Processing,
10. The circuit generation support method according to claim 9, wherein, in the fourth process, the circuit type code is commented, and a description corresponding to the specification of the target hardware is inserted next to the comment.   The fourth process displays an input window for parameters to be given to one candidate selected from the description library, and generates a description according to the parameter specified in the input window and replaces the parameter. 10. The circuit design support method according to 10.

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