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coder.CodeConfig

Configuration parameters for C/C++ code generation from MATLAB code

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Description

A coder.CodeConfig object contains the configuration parameters that codegen uses for generating a static library, a dynamically linked library, or an executable program. Pass the object to the codegen function by using the -config option.

Creation

Create a coder.CodeConfig object by using the coder.config function.

Once you create a coder.CodeConfig object, you can modify its properties programmatically at the command line or interactively by using the Configuration Parameter Dialog Box. See Specify Configuration Parameters in Command-Line Workflow Interactively.

Properties

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Compiler optimization or debug settings for toolchain, specified as one of the values in this table.

ValueDescription
'Faster Builds'

Optimizes the build for shorter build times.

'Faster Runs'

Optimizes the build for faster running executables.

'Debug'

Optimizes the build for debugging.

'Specify'

Enables the CustomToolchainOptions property for customization of settings for tools in the selected toolchain. If the Toolchain property is set to 'Automatically locate an installed toolchain', then setting BuildConfiguration to 'Specify' changes Toolchain to the located toolchain.

If you set the Toolchain property to one of the available CMake toolchain definitions, the allowed values of this property are 'Release', 'Debug', 'RelWithDebInfo', 'MinSizeRel', and 'Specify'. See Configure CMake Build Process.

Dynamic array optimization, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator improves the execution time of generated C code by optimizing dynamic array access.

false

The code generator does not optimize dynamic array access.

See Optimize Dynamic Array Access.

Code formatting options for generated code, specified as one of the values in the table.

ValueDescription
'Clang-format'

The code generator formats the generated code according to a clang-format file.

'Auto'

Uses an internal heuristic to determine if the generated code is formatted by clang-format or a MathWorks® formatting tool.

If the code configuration property Verbosity is set to 'Verbose', the code generator produces a warning if the heuristic chooses a MathWorks formatting tool.

'MathWorks'

Causes the code generator to revert to the MathWorks formatting tool.

clang-format does not have native CUDA® C++ support. When generating CUDA code using GPU Coder™, setting the formatting tool to 'Clang-format' might result in build failures during code compilation.

Code replacement library for generated code, specified as one of the values in this table:

ValueDescription
'None'

This value is the default value.

Does not use a code replacement library.

Named code replacement library

Generates calls to a specific platform, compiler, or standards code replacement library. The list of named libraries depends on:

  • Installed support packages.

  • System target file, language, language standard, and device vendor configuration.

  • Whether you created and registered code replacement libraries, using the Embedded Coder® product.

Compatible libraries depend on these parameters:

  • TargetLang

  • TargetLangStandard

  • ProdHWDeviceType in the hardware implementation configuration object.

Embedded Coder offers more libraries and the ability to create and use custom code replacement libraries.

MATLAB® Coder™ generates the minimal set of #include statements for header files required by the selected code replacement library.

Before setting this parameter, verify that your compiler supports the library that you want to use. If you select a parameter value that your compiler does not support, compiler errors can occur.

Note

MATLAB Coder software does not support TLC callbacks.

Maximum number of function specializations for compile-time recursion, specified as a positive integer. To disallow recursion in the MATLAB code, set CompileTimeRecursionLimit to 0. The default compile-time recursion limit is large enough for most recursive functions that require this type of recursion. If code generation fails because of the compile-time recursion limit, and you want compile-time recursion, try to increase the limit. Alternatively, change your MATLAB code so that the code generator uses run-time recursion. See Compile-Time Recursion Limit Reached.

Maximum number of instructions that the constant folder executes. In some situations, code generation requires specific instructions to be constant. If constant folding stops before these instructions are constant-folded, code generation fails. In this case, increase the value of ConstantFoldingTimeout.

See MATLAB Coder Optimizations in Generated Code.

Whether to generate C++ code that contains enumeration classes, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator converts MATLAB enumerations to enumeration classes in the generated C++ code. This option is only supported if TargetLangStandard is set to C++11 or a newer standard.

See Code Generation for Enumerations.

false

The code generator converts MATLAB enumerations to ordinary C enumerations in the generated C++ code.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Name of interface class when you generate C++ code with CppInterfaceStyle set to 'Methods'. In this case, the generated code for MATLAB entry-point functions consists of methods contained in a C++ class with name specified by CppInterfaceClassName. This property has no effect when you set CppInterfaceStyle to 'Functions'.

See Generate C++ Code with Class Interface.

Style of interface to the generated C++ code for the MATLAB entry-point functions that you generate code from. By default, entry-point functions become C++ functions. If you choose 'Methods', then entry-point functions become methods in a C++ class. Specify the name of the class by using the property CppInterfaceClassName.

See Generate C++ Code with Class Interface.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Namespace for the generated C++ code. The code generator does not produce code in a namespace unless you specify a nonempty character vector.

See Organize Generated C++ Code into Namespaces.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Namespace for the C++ code generated for MathWorks code. The code generator does not produce such a namespace if you specify this property as an empty character vector.

See Organize Generated C++ Code into Namespaces.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Data Types: char

Whether to generate C++ classes or C style structures for MATLAB classes, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator produces C++ classes for MATLAB classes. See Generate C++ Classes for MATLAB Classes.

false

The code generator produces C style structures for MATLAB classes.

When using GPU Coder, the code generator always disables this parameter.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Data Types: logical

Whether to generate C++ namespaces for the namespaces in your MATLAB code, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator produces C++ namespaces for the namespaces in your MATLAB code. See Organize Generated C++ Code into Namespaces.

false

The code generator does not produce C++ namespaces for the namespaces in your MATLAB code.

Dependency:

  • Setting TargetLang to 'C++' enables this parameter.

Data Types: logical

Callback class for BLAS library calls in code generated for certain low-level vector and matrix operations in MATLAB code, specified as a character vector.

If you specify a BLAS callback class, for certain low-level vector and matrix functions, the code generator produces BLAS calls by using the CBLAS C interface to your BLAS library. The callback class provides the name of your CBLAS header file, the names of CBLAS data types, and the information required to link to your BLAS library. If this parameter is empty, the code generator produces code for matrix functions instead of a BLAS call.

See Speed Up Matrix Operations in Generated Standalone Code by Using BLAS Calls.

Callback class for FFTW library calls in code generated for FFT functions in MATLAB code, specified as a character vector.

To improve the execution speed of FFT functions, the code generator produces calls to the FFTW library that you specify in the callback class. If this parameter is empty, the code generator uses its own algorithms for FFT functions instead of calling the FFTW library.

UseBuiltinFFTWLibrary takes precedence over CustomFFTCallback if you enable both these properties.

See Speed Up Fast Fourier Transforms in Generated Standalone Code by Using FFTW Library Calls.

Custom code that appears near the top of each C/C++ header file generated from your MATLAB code, except rtwtypes.h and rtwhalf.h, specified as a character vector.

Include folders to add to the include path when compiling the generated code. Specify the list of include folders as a string array, cell array of character vector, or character vector.

To specify a single include folder, you can use a character vector or a string scalar.

To specify multiple folder names, use one of the values in this table.

ValueDescription
String array

A string array in CustomInclude. For example, cfg.CustomInclude = ["C:\Project","C:\Custom Files"];

Cell array of character vectors

A cell array of character vectors in CustomInclude. For example, cfg.CustomInclude = {'C:\Project','C:\Custom Files'};

Custom code to include in the generated initialize function, specified as a character vector.

Callback class for LAPACK library calls in code generated for certain linear algebra functions in MATLAB code, specified as a character vector.

If you specify a LAPACK callback class, for certain linear algebra functions, the code generator produces LAPACK calls by using the LAPACKE C interface to your LAPACK library. The callback class provides the name of your LAPACKE header file and the information required to link to your LAPACK library. If this parameter is empty, the code generator produces code for linear algebra functions instead of a LAPACK call.

See Speed Up Linear Algebra in Generated Standalone Code by Using LAPACK Calls.

Static library files to link with the generated code, specified as a string array, cell array of character vector, or character vector.

To specify a single static library file, you can use a character vector or a string scalar.

To specify multiple static library file names, use one of the values in this table.

ValueDescription
String array

A string array in CustomLibrary. For example, cfg.CustomLibrary = ["myLib1.lib","myLib2.lib"];

Cell array of character vectors

A cell array of character vectors in CustomLibrary. For example, cfg.CustomLibrary = {'myLib1.lib','myLib2.lib'};

Source files to compile and link with the generated code, specified as a string array, cell array of character vector, or character vector.

The build process searches for the source files first in the current folder, and then in the include folders that you specify in CustomInclude. If source files with the same name occur in multiple folders on the search path, the build process might use a different file than the file that you specified.

Suppose that you specify foo.cpp as a source file. If foo.c and foo.cpp are both on the search path, you cannot be sure whether the build process uses foo.c or foo.cpp.

To specify a single source file, you can use a character vector or a string scalar.

To specify multiple source file names, use one of the values in this table.

ValueDescription
String array

A string array in CustomSource. For example, cfg.CustomSource = ["mySrc1.c","mySrc2.c"];

Cell array of character vectors

A cell array of character vectors in CustomSource. For example, cfg.CustomSource = {'mySrc1.c','mySrc2.c'};

Specify code to appear near the top of each generated .c or .cpp file (except rtwhalf.c or rtwhalf.cpp), outside of any function. Specify code as a character vector.

Do not specify a C static function definition.

Code that appears in the generated terminate function, specified as a character vector.

Custom settings for tools in selected toolchain, specified as a cell array.

Dependencies:

  • The Toolchain property determines which tools and options appear in the cell array.

  • Setting the BuildConfiguration property to Specify enables CustomToolchainOptions.

First, get the current settings. For example:

cfg = coder.config('lib');
cfg.BuildConfiguration='Specify';
opt = cfg.CustomToolchainOptions

Then, edit the values in opt.

These values derive from the toolchain definition file and the third-party compiler options. See Custom Toolchain Registration.

Data type replacement in generated code, specified as one of the values in this table.

ValueDescription
'CBuiltIn'

This value is the default value.

The code generator uses built-in C data types.

'CoderTypeDefs'The code generator uses predefined data types from rtwtypes.h

Configuration object for code generation for deep learning networks, specified as specified as one of the objects in this table.

ObjectRequiresDescription
coder.MklDNNConfig

  • Deep Learning Toolbox™

  • MATLAB Coder Interface for Deep Learning support package

A coder.MklDNNConfig object contains parameters specific to C++ code generation for deep learning using Intel® MKL-DNN. To create a coder.MklDNNConfig object, use coder.DeepLearningConfig. For example: 

cfg = coder.config('mex');
cfg.TargetLang = 'C++';
cfg.DeepLearningConfig = coder.DeepLearningConfig('mkldnn');

See Code Generation for Deep Learning Networks with MKL-DNN.

coder.ARMNEONConfig

  • Deep Learning Toolbox

  • MATLAB Coder Interface for Deep Learning support package

A coder.ARMNEONConfig object contains parameters specific to C++ code generation for deep learning using the ARM® Compute Library. To create a coder.ARMNEONConfig object, use coder.DeepLearningConfig. For example: 

cfg = coder.config('lib');
cfg.TargetLang = 'C++';
cfg.DeepLearningConfig = coder.DeepLearningConfig('arm-compute');

See Code Generation for Deep Learning Networks with ARM Compute Library.

coder.CuDNNConfig (GPU Coder)

  • Deep Learning Toolbox

  • GPU Coder

  • GPU Coder Interface for Deep Learning support package

A coder.CuDNNConfig object contains parameters specific to CUDA code generation for deep learning using the cuDNN library. To create a coder.CuDNNConfig object, use coder.DeepLearningConfig. For example: 

cfg = coder.gpuConfig('lib');
cfg.TargetLang = 'C++';
cfg.DeepLearningConfig = coder.DeepLearningConfig('cudnn');

See Code Generation for Deep Learning Networks by Using cuDNN (GPU Coder).

coder.TensorRTConfig (GPU Coder)

  • Deep Learning Toolbox

  • GPU Coder

  • GPU Coder Interface for Deep Learning support package

A coder.TensorRTConfig object contains parameters specific to CUDA code generation for deep learning using the TensorRT library. To create a coder.TensorRTConfig object, use coder.DeepLearningConfig. For example: 

cfg = coder.gpuConfig('lib');
cfg.TargetLang = 'C++';
cfg.DeepLearningConfig = coder.DeepLearningConfig('tensorrt');

See Code Generation for Deep Learning Networks by Using TensorRT (GPU Coder).

Dependency: If DeepLearningConfig is set, codegen sets TargetLang to C++.

Object description, specified as a character vector.

Dynamic memory allocation mode, specified as one of the values in this table.

ValueDescription
'Threshold'

This value is the default value.

The code generator allocates memory dynamically on the heap for variable-size arrays whose size (in bytes) is greater than or equal to DynamicMemoryAllocationThreshold.

'AllVariableSizeArrays'The code generator dynamically allocates memory for all variable-size arrays on the heap.
'Off'

The code generator statically allocates memory for variable-size arrays on the stack.

Unbounded variable-size arrays require dynamic memory allocation.

Dependencies:

  • EnableVariableSizing enables this parameter.

  • Setting this DynamicMemoryAllocation to 'Threshold' enables the DynamicMemoryAllocationThreshold parameter.

See Generate Code for Variable-Size Data.

Note

DynamicMemoryAllocation configuration option will be removed in a future release. To dynamically allocation memory for variable-sized arrays, use the EnableDynamicMemoryAllocation option. Use the DynamicMemoryAllocationThreshold option to configure the dynamic memory allocation threshold value.

Dynamic memory allocation for fixed-size arrays, specified as one of the values in this table.

ValueDescription
true

The code generator allocates memory dynamically on the heap for fixed-size arrays whose size (in bytes) is greater than or equal to DynamicMemoryAllocationThreshold.

false

This value is the default value.

The code generator statically allocates memory for fixed-size arrays on the stack.

Dependency:

  • Setting EnableDynamicMemoryAllocation to true enables this option.

See, Control Dynamic Memory Allocation for Fixed-Size Arrays.

Implementation of dynamically allocated array at the interface of the generated C/C++ function, specified as one of the values in this table.

ValueDescription
'Auto'

This is the default value. If you set the TargetLang parameter to 'C++' or 'C', this value correspondingly behaves as the same option.

'C'

The generated code uses the C style emxArray data structure to implement dynamically allocated arrays. See Use C Arrays in the Generated Function Interfaces.

'C++'

If you set the TargetLang parameter to 'C', this value is disabled.

Otherwise, the generated code uses the coder::array class template to implement dynamically allocated arrays. See Use Dynamically Allocated C++ Arrays in Generated Function Interfaces.

When using GPU Coder, the code generator always uses the C style emxArray data structure.

Dependency:

  • EnableVariableSizing enables this parameter.

Size threshold for dynamic memory allocation of variable-size arrays, specified as a positive integer. The code generator uses dynamic memory allocation for variable-size arrays whose size (in bytes) is greater than or equal to the threshold.

Dependency:

  • Setting EnableDynamicMemoryAllocation to true enables this option.

See Generate Code for Variable-Size Data.

Automatic extrinsic function calls, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator treats some common visualization functions as extrinsic functions. You do not have to declare these functions as extrinsic by using coder.extrinsic. This capability reduces the amount of time that you spend making your code suitable for code generation.

falseThe code generator does not treat common visualization functions as extrinsic functions unless you declare them as extrinsic by using coder.extrinsic.

Some common visualization functions are plot, disp, and figure. See Use MATLAB Engine to Execute a Function Call in Generated Code.

Automatic parallelization of for loops, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

Code generator does not automatically parallelize for loops.

true

The code generator automatically parallelizes for loops in the generated code. Automatic parallelization can significantly improve the execution speed of the generated code. See Automatically Parallelize for Loops in Generated Code.

When using GPU Coder, the code generator always enables automatic parallelization of for loops.

Data Types: logical

Reporting for automatic parallelization of for loops, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

If you set EnableAutoParallelization to true, the code generator produces a code generation report for automatic parallelization of for loops.

falseThe code generator does not produce a code generation report for automatic parallelization of for loops.

Dynamic memory allocation for variable-size arrays, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator allocates memory dynamically on the heap for variable-size arrays whose size (in bytes) is greater than or equal to DynamicMemoryAllocationThreshold.

falseThe code generator statically allocates memory for variable-size arrays on the stack.

Implicit expansion capabilities in the generated code, specified as one of the values listed in this table.

ValueDescription
true

This value is the default value.

The code generator enables implicit expansion in the generated code. The code generator includes modifications in the generated code to apply implicit expansion. See Compatible Array Sizes for Basic Operations.

false

The generated code does not follow the rules of implicit expansion.

Data Types: logical

memcpy optimization, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

If possible, the code generator uses the memcpy optimization. To optimize code that copies consecutive array elements, the memcpy optimization replaces the code with a memcpy call. When the number of elements to copy is known at compile time, the code generator uses the MemcpyThreshold property to determine whether to use the optimization. See memcpy Optimization.

false

The code generator does not use the memcpy optimization.

When using GPU Coder, the code generator always disables Memcpy optimization.

Parallelization of parfor-loops, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

If possible, the code generator uses the OpenMP library to produce loop iterations that run in parallel.

false

The code generator treats parfor-loops as for-loops.

See parfor.

Use of the OpenMP library is not compatible with just-in-time (JIT) compilation. If EnableJIT and EnableOpenMP are true, the code generator uses JIT compilation and treats parfor-loops as for-loops.

When using GPU Coder, the code generator always treats parfor-loops as for-loops.

Run-time recursion support, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

Recursive functions are allowed in the generated code.

false

Recursive functions are not allowed in the generated code.

Some coding standards, such as MISRA™, do not allow recursion. To increase the likelihood of generating code that is compliant with MISRA C™, set EnableRuntimeRecursion to false.

If your MATLAB code requires run-time recursion and EnableRuntimeRecursion is false, code generation fails.

See Code Generation for Recursive Functions.

Variable-size array support, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

Variable-size arrays are allowed for code generation.

false

Variable-size arrays are not allowed for code generation.

Dependency:

  • Enables Dynamic memory allocation.

See Code Generation for Variable-Size Arrays.

File partitioning mode specified as one of the values in this table.

ValueDescription
'MapMFileToCFile'

This value is the default value.

The code generator produces separate C/C++ files for each MATLAB language file.

'SingleFile'The code generator produces a single file for C/C++ functions that map to your MATLAB entry-point functions. The code generator produces separate C/C++ files for utility functions.

See How MATLAB Coder Partitions Generated Code.

Generation of only source code, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator produces C/C++ source code and builds object code.

true

The code generator produces C/C++ source code, but does not invoke the make command or build object code. When you iterate between modifying MATLAB code and generating C/C++ code, generating only code can save time.

Comments in generated code, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator places comments in the generated code.

falseThe code generator does not place comments in the generated code.

If you set GenerateComments to true, the code generator places default comments, such as inferred argument types, in the generated code. The code generator also copies code comments that you make inside your MATLAB functions into the generated code, with some exceptions. For example, the generated code generally does not include code comments from MATLAB functions that are removed due to internal optimizations.

If you generate code for a live function (.mlx file), the code generator does not include the text sections in the generated code, even if GenerateComments is set to true. To include live function text sections as comments in the generated code, first save the .mlx file as a .m file, which converts the text sections to code comments within the function body. Because the code generator gives precedence to functions in .mlx files over those in .m files, you must rename one of the functions or move one of the files to a different folder. Then, generate code for the function in the .m file. The code generator includes the text sections as comments in the generated code.

Example C/C++ main file generation, specified as one of the values in this table.

ValueDescription
'GenerateCodeOnly'

This value is the default value.

The code generator generates an example C/C++ main function but does not compile it.

'DoNotGenerate'

The code generator does not generate an example C/C++ main function.

'GenerateCodeAndCompile'

The code generator generates an example C/C++ main function and compiles it to create a test executable. This executable does not return output.

If the GenCodeOnly parameter is true, the code generator does not compile the C/C++ main function.

An example main function is a template to help you to write a C/C++ main function that calls generated C/C++ code. See Incorporate Generated Code Using an Example Main Function.

Makefile generation during the build process, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator generates a makefile during the build process.

falseThe code generator does not generate a makefile during the build process. Specify instructions for post-code-generation processing, including compilation and linking, in a post-code-generation command. See Build Process Customization.

Generation of support files for nonfinite data, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator produces the support files for nonfinite data (Inf and NaN) only if the generated code uses nonfinite data.

false

The code generator always produces the support files for nonfinite data (Inf and NaN).

Dependency:

  • Setting SupportNonFinite to true enables this parameter.

Code generation report, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator produces a report only if error or warning messages occur, or if you set LaunchReport to true.

trueThe code generator produces a code generation report.

Configuration object for generating CUDA GPU code using GPU Coder. A GpuCodeConfig object contains parameters specific to CUDA GPU code generation. To create a GpuCodeConfig object, use coder.gpuConfig (GPU Coder). For example: 

cfg = coder.gpuConfig('lib');
cfg.GpuConfig

ans =
   GpuCodeConfig with properties:

                    Enabled: 1
                 MallocMode: 'discrete'
           KernelNamePrefix: ''
               EnableCUBLAS: 1
             EnableCUSOLVER: 1
                EnableCUFFT: 1
               Benchmarking: 0
                  SafeBuild: 0
          ComputeCapability: 'Auto'
    CustomComputeCapability: ''
              CompilerFlags: ''
        StackLimitPerThread: 1024
            MallocThreshold: 200
     MaximumBlocksPerKernel: 0
        EnableMemoryManager: 1
           SelectCudaDevice: -1

For more information, see Generate Code Using the Command Line Interface (GPU Coder).

Dependencies: If GpuConfig is set, codegen modifies the coder.CodeConfig properties to values in this table.

PropertyValue
CppPreserveClassesfalse
DynamicMemoryAllocationInterface'C' when MallocMode property of GpuCodeConfig is set to 'unified'
EnableAutoParallelizationtrue
EnableMemcpyfalse
EnableOpenMPfalse
InstructionSetExtensions'None'
MultiInstanceCodefalse
TargetLang'C++'

Object that specifies a hardware board. To create the coder.Hardware object, use coder.hardware. For example:

cfg = coder.config('lib');
hw = coder.hardware('Raspberry Pi');
cfg.Hardware = hw;

Before you use coder.hardware, you must install the support package for the hardware.

Dependencies:

  • Setting Hardware customizes the hardware implementation object and other configuration parameters for a particular hardware board.

  • If DeepLearningConfig is set to a coder.ARMNEONConfig object and Hardware is empty, then codegen sets the GenCodeOnly property to true.

Note:

  • Suppose that you create a coder.CodeConfig object cfg in a MATLAB session and use it in another MATLAB session. If the MATLAB host computer for the second session does not have the hardware board specified in the cfg.Hardware property installed on it, this parameter reverts to its default value. The default value is []. Setting the Hardware Board option to MATLAB Host Computer in the app is equivalent to using cfg.Hardware and cfg.HardwareImplementation.ProdHWDeviceType with their default value.

Hardware implementation object that specifies hardware-specific configuration parameters for C/C++ code generation. coder.config creates a coder.CodeConfig object with the HardwareImplementation property set to a coder.HardwareImplementation object with default parameter values for the MATLAB host computer.

To prevent compilation errors due to multiple inclusion of header files, the code generator produces either #ifndef or #pragma once constructs in generated header files. If your project uses distinct files that use the same preprocessor macros, then generate code with the #pragma once construct. The compilation behavior of #pragma once is not standardized.

Specify HeaderGuardStyle as one of the values in this table.

ValueDescription
UseIncludeGuard

The code generator produces #ifndef style #include guards.

UsePragmaOnceThe code generator produces #pragma once style #include guards.

Display of potential row-major layout efficiency issues, specified as one of the values in this table.

ValueDescription
true

The code generation report displays potential efficiency issues due to row-major layout. (This value is the default value.)

falseThe code generation report does not display issues related to array layout.

See Code Design for Row-Major Array Layout.

Assignment of float and double zero with memset, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

If possible, the code generator uses the memset optimization for assignment of floating-point zero to consecutive array elements. To assign consecutive array elements, the memset optimization uses a memset call. When the number of elements to assign is known at compile time, the code generator uses the MemcpyThreshold property to determine whether to use the optimization. See memset Optimization.

false

The code generator does not use the memset optimization for assignment of float and double zero to consecutive array elements.

Inlining behavior at all call sites where a MathWorks calls another MathWorks function, specified as one of the values in this table.

ValueDescription
'Speed'

This value is the default value.

Uses internal heuristics to determine whether to perform inlining at a call site. This setting usually leads to highly optimized code.

'Always'

Always performs inlining at a call site.

'Readability'

Almost never inlines function calls, except for calls to very small functions. Preserves modularity of code without sacrificing too much speed, whenever possible. Results in highly readable code.

'Never'

Never inlines function calls. Results in maximum readability. This setting might significantly reduce the performance of the generated code.

Even if you select the 'Always' or the 'Never' option for a setting, in certain cases, the code generator might not strictly follow that instruction. For example, if there is a conflict, the coder.inline('always') or coder.inline('never') directive placed inside a function body overrides this option. For more information, see Control Inlining to Fine-Tune Performance and Readability of Generated Code.

Inlining behavior at all call sites where a function that you wrote calls a MathWorks function, or a MathWorks function calls a function that you wrote. Specified as one of the values in this table.

ValueDescription
'Readability'

This value is the default value.

Almost never inlines function calls, except for calls to very small functions. Preserves modularity of code without sacrificing too much speed, whenever possible. Results in highly readable code.

'Always'

Always performs inlining at a call site.

'Speed'

Uses internal heuristics to determine whether to perform inlining at a call site. This setting usually leads to highly optimized code.

'Never'

Never inlines function calls. Results in maximum readability. This setting might significantly reduce the performance of the generated code.

Even if you select the 'Always' or the 'Never' option for a setting, in certain cases, the code generator might not strictly follow that instruction. For example, if there is a conflict, the coder.inline('always') or coder.inline('never') directive placed inside a function body overrides this option. For more information, see Control Inlining to Fine-Tune Performance and Readability of Generated Code.

Inlining behavior at all call sites where a function that you wrote calls another function that you wrote, specified as one of the values in this table.

ValueDescription
'Speed'

This value is the default value.

Uses internal heuristics to determine whether to perform inlining at a call site. This setting usually leads to highly optimized code.

'Always'

Always performs inlining at a call site.

'Readability'

Almost never inlines function calls, except for calls to very small functions. Preserves modularity of code without sacrificing too much speed, whenever possible. Results in highly readable code.

'Never'

Never inlines function calls. Results in maximum readability. This setting might significantly reduce the performance of the generated code.

Even if you select the 'Always' or the 'Never' option for a setting, in certain cases, the code generator might not strictly follow that instruction. For example, if there is a conflict, the coder.inline('always') or coder.inline('never') directive placed inside a function body overrides this option. For more information, see Control Inlining to Fine-Tune Performance and Readability of Generated Code.

Instruction sets to generate single instruction, multiple data (SIMD) code for target hardware. The code generator loads the selected instruction set and the instruction sets that it depends on.

If you select Auto, the default setting, the code generator selects an instruction set according to your hardware board:

  • MATLAB Host Computer, Intel, or AMD® － SSE2

  • ARM

    － None

See Generate SIMD Code from MATLAB Functions for Intel Platforms.

When using GPU Coder, the code generator always disables InstructionSetExtensions.

Annotates the generated C/C++ code to suppress known MISRA and AUTOSAR violations, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator does not add annotations to the generated C/C++ code.

trueThe code generator adds annotations to the generated C/C++ code only if GenerateComments is also true.

Whether the code generator embeds large constants for a deep neural network (DNN) in the generated source code or writes these constants to binary data files, specified as one of the values in the following table. To specify the threshold (in bytes) above which the DNN constants are written to binary data files, set the LargeConstantThreshold property. The default value of this property is 131072.

This property is applicable only if you generate code that does not depend on third-party deep learning libraries.

ValueDescription
'WriteOnlyDNNConstantsToDataFiles'

This value is the default value.

The code generator writes large constants for a deep neural network (DNN) in binary data files.

'KeepInSourceFiles'

The code generator embeds large constants for a deep neural network (DNN) in the generated source code.

The generated binary data files are located in the code generation folder and are loaded by the generated code at run time. If you relocate these files, set the environment variable CODER_DATA_PATH to this new location before running the generated code.

The code generator always embeds the non-DNN constants in the generated source code, irrespective of the sizes of these constants.

Dependency:

  • EnableDynamicMemoryAllocation enables this parameter.

The LargeConstantThreshold property specifies the threshold (in bytes) above which the constants for a deep neural network (DNN) are written to binary data files. The code generator by default sets this threshold to 131072 bytes. Depending on your application, you can set this threshold to a different integer value.

This property is applicable only if you generate code that does not depend on third-party deep learning libraries.

Dependencies: To enable this property, perform both these actions.

  • Set EnableDynamicMemoryAllocation to true.

  • Set LargeConstantGeneration to 'WriteOnlyDNNConstantsToDataFiles'.

Automatic open of code generation report, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

If errors or warnings occur, or if GenerateReport is true, the code generator produces a report, but does not open the report.

trueThe code generator produces and opens a code generation report.

Loops with fewer iterations than this threshold are candidates for automatic unrolling by the code generator. This threshold applies to all for-loops and parfor-loops in your MATLAB code. For an individual for-loop, a coder.unroll directive placed immediately before the loop takes precedence over the loop unrolling optimization. The threshold can also apply to some for-loops produced during code generation.

See Unroll for-Loops and parfor-Loops.

Inclusion of MATLAB source code as comments in generated code, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator does not insert MATLAB source code as comments in the generated code. The code generator does not include the MATLAB function signature in the function banner.

true

The code generator inserts MATLAB source code as comments in the generated code. A traceability tag immediately precedes each line of source code. The traceability tag helps you to locate the corresponding MATLAB source code. See Tracing Generated C/C++ Code to MATLAB Source Code.

If you have Embedded Coder, in the code generation report, the traceability tag links to the source code.

The code generator also includes the MATLAB function signature in the function banner.

Dependency:

  • Setting GenerateComments to true enables this parameter.

See Tracing Generated C/C++ Code to MATLAB Source Code.

Whether to include line numbers of MATLAB source code as comments in the generated code, specified as true or false.

Dependency:

  • MATLABSourceComments enables this parameter.

Maximum number of characters in generated identifiers, specified as a positive integer in the range [31, 2048]. This property applies to generated function, type definition, and variable names. To avoid truncation of identifiers by the target C/C++ compiler, specify a value that matches the maximum identifier length of the target C/C++ compiler.

This property does not apply to exported identifiers, such as the generated names for entry-point functions or emxArray API functions. If the length of an exported identifier exceeds the maximum identifier length of the target C compiler, the target C/C++ compiler truncates the exported identifier.

Default values:

  • If TargetLang is set to 'C', the default value of MaxIdLength is 31.

  • If TargetLang is set to 'C++', the default value of MaxIdLength is 1024.

Minimum size, in bytes, for memcpy or memset optimization, specified as a positive integer.

To optimize generated code that copies consecutive array elements, the code generator tries to replace the code with a memcpy call. To optimize generated code that assigns a literal constant to consecutive array elements, the code generator tries to replace the code with a memset call.

The number of bytes is the number of array elements to copy or assign multiplied by the number of bytes required for the C/C++ data type.

If the number of elements to copy or assign is variable (not known at compile time), the code generator ignores the MemcpyThreshold property.

See memcpy Optimization and memset Optimization.

Multi-instance, reentrant code, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator does not produce multi-instance, reentrant code.

true

The code generator produces reusable, multi-instance code that is reentrant.

See Reentrant Code.

This option is not supported by the GPU Coder product.

Object name, specified as a character vector.

Maximum number of CPU threads to run parallel for-loops in the generated C/C++ code, specified as a positive integer.

See Specify Maximum Number of Threads to Run Parallel for-Loops in the Generated Code.

To generate SIMD code for reduction operations, use one of the values as specified in this table.

ValueDescription
false

This value is the default value.

Code generator does not generate SIMD code for reduction operations.

true

To use this parameter, you must select an instruction set for the InstructionSetExtensions parameter. The code generator uses the specified instruction set to generate SIMD code for reduction operations.

See Generate SIMD Code from MATLAB Functions for Intel Platforms.

To generate parallel for-loops performing reduction operations, use one of the values as specified in this table.

ValueDescription
false

This value is the default value.

Code generator does not automatically parallelize for-loops performing reduction operations.

true

The code generator automatically parallelizes for-loops performing reduction operations in the generated code, only if you set EnableAutoParallelization to true.

See Reduction Operations Supported for Automatic Parallelization of for-loops.

Note

Vectorizing and parallelizing reduction operations might introduce slight numerical deviations. For more information, see Handling Overflow in Automatic Parallelization of for-loops.

Output to build from generated C/C++ code, specified as one of the values in this table.

ValueDescription
'LIB'Static library
'DLL'Dynamically linked library
'EXE'Executable program

Pass structures by reference to entry-point functions, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The generated code passes structures by reference, which reduces memory usage and execution time by minimizing the number of copies of parameters at entry-point function boundaries.

Note

An entry-point function that writes to a field of a structure parameter overwrites the input value.

falseThe generated code passes structures by value.

This parameter applies only to entry-point functions.

See Pass Structure Arguments by Reference or by Value in Generated Code.

Command to customize build processing after MEX function generation with codegen, specified as a character vector.

See Build Process Customization.

Generation of code that uses N-dimensional indexing, specified as one of the values in this table.

ValueDescription
false

Generate code that uses one-dimensional indexing. (This value is the default value.)

trueGenerate code that uses N-dimensional indexing.

See Generate Code That Uses N-Dimensional Indexing.

Since R2024b

Whether to protect entry-point input data from modification when the generated code is called from your custom C/C+ code, specified as false or true. See Generate Code That Preserves Entry-Point Input Data.

If you enable this setting, the generated code might include extra copies of the input data. If you pass large-size data, this behavior might increase the execution time and memory use of the generated code.

If you generate code for a MATLAB entry-point function that uses the same variable as both an input and an output, the code generator does not preserve this input data even when you set the PreserveInputData configuration property to true. See Avoid Data Copies of Function Inputs in Generated Code.

Variable names to preserve in the generated code, specified as one of the values in this table.

ValueDescription
'None'

This value is the default value.

The code generator does not have to preserve any variable names. It can reuse any variables that meet the requirements for variable reuse.

If your code uses large structures or arrays, setting PreserveVariableNames to 'None' can reduce memory usage or improve execution speed.

'UserNames'

The code generator preserves names that correspond to variables that you define in the MATLAB code. It does not replace your variable name with another name and does not use your name for another variable. To improve readability, set PreserveVariableNames to 'UserNames'. Then, you can more easily trace the variables in the generated code back to the variables in your MATLAB code.

Setting PreserveVariableNames to 'UserNames' does not prevent an optimization from removing your variables from the generated code or prevent the C/C++ compiler from reusing the variables in the generated binary code.

'All'

Preserve all variable names. This parameter value disables variable reuse. Use it only for testing or debugging, not for production code.

See Preserve Variable Names in Generated Code.

Name of variable to which you export information about code generation, specified as a character vector. The code generator creates this variable in the base MATLAB workspace. This variable contains information about code generation settings, input files, generated files, and code generation messages.

See Access Code Generation Report Information Programmatically and coder.ReportInfo Properties.

Potential difference reporting, specified as one of the values in this table:

ValueDescription
trueThe code generator reports potential behavior differences between generated code and MATLAB code. The potential differences are listed on a tab of the code generation report. A potential difference is a difference that occurs at run time only under certain conditions.
falseThe code generator does not report potential differences.

See Potential Differences Reporting.

List of names that the code generator must not use for functions or variables, specified as a string arrays, cell array of character vectors, or character vector.

Multiple reserved names, specified as one of the values in this table.

ValueDescription
String arrays

A string array in ReservedNameArray. For example, cfg.ReservedNameArray = ["reserve1","reserve2","reserve3"].

Cell array of character vectors

A cell array of character vectors in ReservedNameArray. For example, cfg.ReservedNameArray = {'reserve1','reserve2','reserve3'}.

Character vectors

A semicolon-separated list of reserved names in ReservedNameArray. For example, cfg.ReservedNameArray = 'reserve1;reserve2;reserve3'.

Note

Specifying multiple entries in code configuration objects by using character vectors will be removed in a future release. Use string array and cell array of character vector instead. For more information, see Compatibility Considerations.

Generation of code that uses row-major array layout, specified as one of the values in this table.

ValueDescription
false

Generate code that uses column-major array layout. (This value is the default value.)

trueGenerate code that uses row-major array layout.

See Generate Code That Uses Row-Major Array Layout.

Generation of a call to the initialize function at the beginning of the generated entry-point functions, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

A call to the initialize function is included at the beginning of the generated entry-point functions. The generated code includes checks to make sure that the initialize function is called only once, even if there are multiple entry-point functions.

false

The generated entry-point functions do not include calls to the initialize function.

See Use Generated Initialize and Terminate Functions.

Dependency:

  • Setting MultiInstanceCode to true disables this parameter.

Run-time error detection and reporting in generated code, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The generated code does not check for errors such as out-of-bounds array indexing.

true

The generated code checks for errors such as out-of-bounds array indexing.

The error-reporting software uses fprintf to write error messages to stderr. It uses abort to terminate the application. If fprintf and abort are not available, you must provide them. The abort function abruptly terminates the program. If your system supports signals, you can catch the abort signal (SIGABRT) so that you can control the program termination.

Error messages are in English.

See Generate Standalone C/C++ Code That Detects and Reports Run-Time Errors.

Integer overflow support, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

The code generator produces code to handle integer overflow. Overflows saturate to either the minimum or maximum value that the data type can represent.

false

The code generator does not produce code to handle integer overflow. Do not set SaturateOnIntegerOverflow to false unless you are sure that your code does not depend on integer overflow support. If you disable integer overflow support and run-time error checking is enabled, the generated code produces an error for overflows. If you disable integer overflow support and you disable run-time error checking, the overflow behavior depends on your target C compiler. In the C standard, the behavior for integer overflow is undefined. However, most C compilers wrap on overflow.

This parameter applies only to MATLAB built-in integer types. It does not apply to doubles, singles, or fixed-point data types.

See Disable Support for Integer Overflow or Nonfinites.

Maximum stack usage per application, in bytes, specified as a positive integer. Set a limit that is lower than the available stack size. Otherwise, a run-time stack overflow might occur. The C compiler detects and reports stack overflows.

See Disable Support for Integer Overflow or Nonfinites.

Support for nonfinite values, specified as one of the values in this table.

ValueDescription
true

This value is the default value.

If GenerateNonFiniteFilesIfUsed is set to true, the code generator produces code to support nonfinite values (Inf and NaN) only if they are used.

If GenerateNonFiniteFilesIfUsed is set to false, the code generator always produces code to support nonfinite values (Inf and NaN).

false

The code generator does not produce code to support nonfinite values.

See Disable Support for Integer Overflow or Nonfinites.

Language to use in generated code, specified as 'C' or 'C++'.

When using GPU Coder, the code generator sets TargetLang to C++.

Dependency: If DeepLearningConfig is set, codegen sets TargetLang to C++.

Language standard to use for the generated code, specified as one of these options:

  • 'Auto'

  • 'C89/C90 (ANSI)'

  • 'C99 (ISO)'

  • 'C++03 (ISO)'

  • 'C++11 (ISO)'

  • 'C++14 (ISO)'

  • 'C++17 (ISO)'

  • 'C++20 (ISO)'

Selecting the 'Auto' option sets the TargetLangStandard property based on the value of the TargetLang property. For C, the default standard is 'C99 (ISO)'. For C++, the default standard is 'C++11 (ISO)'. The code generator uses the language features and the math libraries available in the selected C/C++ standard. See Change Language Standard Used for Code Generation.

Toolchain to use for building a C/C++ library or executable program, specified as a character vector. The list of available toolchains depends on the host computer platform, and can include custom toolchains that you added. If you do not specify a toolchain, the code generator locates an installed toolchain.

Note:

  • Suppose that you create a coder.CodeConfig object cfg in a MATLAB session and use it in another MATLAB session. If the MATLAB host computer for the second session does not have the toolchain specified in the cfg.Toolchain property installed on it, this parameter reverts to its default value. The default value is 'Automatically locate an installed toolchain'.

Whether to generate code that produces calls to the FFTW library shipped with MATLAB for fast Fourier transform (FFT) functions in your MATLAB code, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator does not produce calls to the built-in FFTW library for FFT functions in your MATLAB code.

true

The code generator produces calls to the built-in FFTW library for FFT functions in your MATLAB code.

UseBuiltinFFTWLibrary takes precedence over CustomFFTCallback if you enable both these properties.

Data Types: logical

Since R2024b

Extent to which the generated code uses platform-specific precompiled libraries, specified as one of the values in this table.

ValueInstruction Sets
'Prefer'

For C/C++ code generation, this value is the default value.

The code generator prefers to use the available platform-specific precompiled libraries.

This setting is an appropriate choice when you want to optimize the performance of the generated code for specific platforms.

'Avoid'

For CUDA code generation (requires GPU Coder), this value is the default value.

The code generator uses platform-specific precompiled libraries only if no alternative implementations of their algorithms are available.

This setting is useful when you want to create portable applications that can run on many platforms.

For certain precompiled libraries (for example, BLAS, LAPACK, and FFTW), there exist individual configuration parameters that allow you to customize their usage. The UsePrecompiledLibraries parameter does not affect the use of these libraries.

Code generation progress display, specified as one of the values in this table.

ValueDescription
false

This value is the default value.

The code generator does not display code generation progress.

true

The code generator displays code generation progress, including code generation stages and compiler output.

Whether to display the status of the code generation progress at the MATLAB command line, specified as one of the values in this table.

ValueDescription
'Silent'

If code generation succeeds without warning, all messages are suppressed, including when you generate a report.

Warning and error messages are displayed.

'Info'

This value is the default value.

Compared to the 'Silent' mode, if code generation succeeds, these additional messages are displayed:

  • Code generation successful

  • Link to the generated report, if one has been generated

'Verbose'

In addition to the messages shown in the 'Info' mode, code generation status and target build log messages are displayed.

Examples

collapse all

Write a MATLAB function from which you can generate code. This example uses the function myadd that returns the sum of its inputs.

function c = myadd(a,b)
c = a + b;
end

Create a configuration object for generation of standalone C/C++ code (a static library, a dynamically linked library, or an executable program). For example, create a configuration object for generation of a static library.

cfg = coder.config('lib');

Change the values of the properties for which you do not want to use the default values. For example, enable run-time error detection and reporting in the generated C/C++ code.

cfg.RuntimeChecks = true;

Generate code by using codegen. Pass the configuration object to codegen by using the -config option. Specify that the input arguments are scalar double.

codegen myadd -config cfg -args {1 1} -report

Alternative Functionality

To use default configuration parameters for build types 'LIB', 'DLL', or 'EXE', use the codegen option -config:lib, -config:dll, or -config:exe, respectively. Then, you do not have to create and pass a configuration object to codegen.

Version History

Introduced in R2011a

expand all

See Also

Functions

Objects

Topics