Create a New Folder and Copy Relevant Files

The following code creates a sub folder in your current working folder (pwd). The new folder contains files that are relevant for this example.

currentDir = pwd;
[~,cgDir] = rtwdemodir();
coderdemo_setup('coderdemo_crl');

Steps for Developing a Code Replacement Library

For more information, see Develop a Code Replacement Library.

Math Function Replacement

This example defines and registers code replacement mappings for math functions. You can define code replacement mappings for a variety of functions. For details, see Code You Can Replace from MATLAB Code.

1. Open and explore the MATLAB® file for this example.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','replace_math_fcns.m'))

2. Configure the code generator to use the code replacement library Function Replacement Examples.

RTW.TargetRegistry.getInstance('reset');
cfg = coder.config('lib','ecoder',true);
cfg.CodeReplacementLibrary = 'Function Replacement Examples';
cfg.GenerateReport = false;
cfg.LaunchReport = false;

3. Set up the configuration parameters to build and define the function input type.

t = single(2); 

4. Explore the code replacement table definition file.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','crl_table_functions.m'))

5. Compile the MATLAB® program into a C source file by using the configuration parameters that point to the code replacement library and the example input class defined in step 3 as input parameters to the codegen command.

codegen('replace_math_fcns', '-config', cfg, '-args', {t, t});

6. Open the file replace_math_fcns.c and explore the generated source code.

open(fullfile('codegen','lib','replace_math_fcns','replace_math_fcns.c'))

7. Close replace_math_fcns.m.

For more information on math function replacement, see Math Function Code Replacement.

Addition and Subtraction Operator Replacement

This example shows how to define and register code replacement mappings for addition (+) and subtraction (-) operations. When defining entries for addition and subtraction operations, you can specify which of the following algorithms (EntryInfoAlgorithm) your library functions implement:

1. Open and explore the MATLAB® file for this example.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','addsub_two_int16.m'))
%
% CBO, the default algorithm, is assumed.

2. Configure the code generator to use a code replacement library Addition & Subtraction Examples.

RTW.TargetRegistry.getInstance('reset');
cfg = coder.config('lib','ecoder',true);
cfg.CodeReplacementLibrary = 'Addition & Subtraction Examples';
cfg.GenerateReport = false;
cfg.LaunchReport = false;

3. Set up the configuration parameters to build and define the operation input type.

t = int16(2); 

4. Explore the code replacement table definition file.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','crl_table_addsub.m'))

5. Compile the MATLAB® program into a C source file by using the configuration parameters that point to the desired code replacement library and the example input class defined in step 3 as input parameters to the codegen command.

codegen('addsub_two_int16','-config', cfg, '-args', {t, t});

6. Open the file addsub_two_int16.c and explore the generated source code.

open(fullfile('codegen','lib','addsub_two_int16','addsub_two_int16.c'))

7. Close addsub_two_int16.m.

For more information on addition and subtraction operator replacement, see Scalar Operator Code Replacement and Addition and Subtraction Operator Code Replacement.

Matrix Operator Replacement

This example defines and registers code replacement mappings for matrix operations: addition, subtraction, multiplication, transposition, conjugate, and Hermitian.

Supported types include:

1. Open and explore the MATLAB® file for this example:

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','replace_matrix_ops.m'))

2. Configure the code generator to use a code replacement library Matrix Op Replacement Examples.

RTW.TargetRegistry.getInstance('reset');
cfg = coder.config('lib','ecoder',true);
cfg.CodeReplacementLibrary = 'Matrix Op Replacement Examples';
cfg.GenerateReport = false;
cfg.LaunchReport = false;

3. Set up the configuration parameters to build and define the operation input type.

t = [1.0 2.0; 3.0, 4.0]; 

4. Explore the code replacement table definition file.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','crl_table_matops.m'))

5. Compile the MATLAB® program using the configuration parameters that point to the desired code replacement library and the example input class defined in step 3 as input parameters to the codegen command.

codegen('replace_matrix_ops', '-config', cfg, '-args', {t, t});

6. Open the file replace_matrix_ops.c and explore the generated source code.

open(fullfile('codegen','lib','replace_matrix_ops','replace_matrix_ops.c'))

7. Close replace_matrix_ops.m.

For more information on matrix operator replacement, see Small Matrix Operation to Processor Code Replacement.

Matrix Multiplication Replacement for BLAS

This example defines and registers code replacement mappings for Basic Linear Algebra Subroutines (BLAS) subroutines xGEMM and xGEMV. You can map the following operations to a BLAS subroutine:

1. Open and explore the MATLAB® file for this example.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','replace_matrix_ops_blas.m'))

2. Configure the code generator to use a code replacement library BLAS Replacement Examples.

RTW.TargetRegistry.getInstance('reset');
cfg = coder.config('lib','ecoder',true);
cfg.CodeReplacementLibrary = 'BLAS Replacement Examples';
cfg.GenerateReport = false;
cfg.LaunchReport = false;

3. Set up the configuration parameters to build and define the function input type.

t = [1.0 2.0 3.0; 4.0 5.0 6.0; 7.0 8.0 9.0]; 

4. Explore the code replacement table definition file.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','crl_table_blas.m'))

5. Compile the MATLAB® program using the configuration parameters that point to the desired code replacement library and the example input class defined in step 3 as input parameters to the codegen command.

codegen('replace_matrix_ops_blas', '-config', cfg, '-args', {t, t});

6. Open the file replace_matrix_ops_blas.c and explore the generated source code.

open(fullfile('codegen','lib','replace_matrix_ops_blas','replace_matrix_ops_blas.c'))

7. Close replace_matrix_ops_blas.m.

For more information on matrix multiplication replacement for BLAS, see Matrix Multiplication Operation to MathWorks BLAS Code Replacement.

MATLAB Function Replacement Using Coder.Replace

Code replacement libraries support the replacement of MATLAB® functions with scalar and matrix inputs and outputs for built-in, complex, and fixed-point data types.

1. Open and explore the MATLAB® file for this example.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','coder_replace_fcn.m'))

2. Configure the code generator to use a code replacement library Coder Replace Examples.

RTW.TargetRegistry.getInstance('reset');
cfg = coder.config('lib','ecoder',true);
cfg.CodeReplacementLibrary = 'Coder Replace Examples';
cfg.GenerateReport = false;
cfg.LaunchReport = false;

3. Set up the configuration parameters to build and define the function input type.

t = [1 2; 3 4];

4. Explore the code replacement table definition file.

edit(fullfile(matlabroot,'toolbox','coder','codegendemos','coderdemo_crl','crl_table_coder_replace.m'))

5. Compile the MATLAB® program using the configuration parameters that point to the desired code replacement library and the example input class defined in step 3 as input parameters to the codegen command.

codegen('coder_replace_fcn', '-config', cfg, '-args', {t, t});

6. Open the file coder_replace_fcn.c and explore the generated source code.

open(fullfile('codegen','lib','coder_replace_fcn','coder_replace_fcn.c'))

7. Close coder_replace_fcn.m.

For more information, see docid:ecoder_ug.mw_ab7cd3a5-076f-40e4-b8a9-d3357993c100.

Build Information

For each entry in a code replacement table, you can specify build information such as the following, for replacement functions:

Additionally, you can specify RTW.copyFileToBuildDir to copy header, source, or object files, which are required to generate replacement code, to the build folder before code generation. You can specify RTW.copyFileToBuildDir by setting it as the value of:

Note: Models in this example are configured for code generation only because the implementations for the replacement functions are not provided.

For more information on specifying build information for replacement code, see Develop a Code Replacement Library.

Cleanup

Remove files and return to original folder

RTW.TargetRegistry.getInstance('reset');
rtwdemoclean;
clear coderdemo_crl
cd ../