Data Copy Reduction

Adjust model parameters to improve code execution speed and reduce memory usage

Reduce RAM and ROM consumption and increase code execution speed by eliminating data copies in the generated code. The code generator eliminates some data copies. You can eliminate other data copies by adjusting certain model parameter settings, specifying the same name for the input and output arguments of MATLAB Function blocks, and by using Simulink signals to specify reuse.

Model Settings

expand all

Data Copy Reduction

Use memcpy for vector assignment	Optimize code generated for vector assignments
Reuse global block outputs	Optimization to reuse global variables
Pass reusable subsystem outputs as	Control how a reusable subsystem passes outputs
Perform in-place updates for Assignment and Bus Assignment blocks	Reuse the input and output variables of Bus Assignment and Assignment blocks
Reuse buffers for Data Store Read and Data Store Write blocks	Eliminate temporary buffers for Data Store Read and Data Store Write blocks
Inline invariant signals	Transform symbolic names of Invariant signals in generated code
Optimize block operation order in generated code	Specify to reorder block operations for improved code execution speed
Eliminate superfluous local variables (Expression folding)	Specify to fold expressions into single expression
Pass reusable subsystem outputs as	Control how a reusable subsystem passes outputs
Signal storage reuse	Reuse signal memory
Use signal labels to guide buffer reuse	Reuse buffers by using signal labels
Optimize global data access	Optimize global variable usage
Function inlining between user functions	Control inlining for calls from user-written functions to other user-written functions (Since R2025a)
Function inlining between MathWorks functions	Control inlining for calls from MathWorks functions to other MathWorks functions (Since R2025a)
Function inlining between user and MathWorks functions	Control inlining for calls from user-written functions to MathWorks functions and from MathWorks functions to user-written functions (Since R2025a)

Topics

Data Copy Reduction Basics

Design Techniques to Optimize Models for Efficient Code Generation
Apply design tools and techniques to optimize a model for code generation.
Optimize Generated Code Using Code Efficiency Tools and Techniques
When generating production code from your model to deploy into a real-time embedded system, code efficiency is an important consideration.
Configure Model for Code Generation Objectives by Using Code Generation Advisor
Use the Code Generation Advisor to check your model against code generation objectives.
Generate Efficient Code by Setting Model Configuration Parameters
Choose the efficiency level and priorities for your generated code.

Data Copy Reduction by Default

Optimize Generated Code by Passing Reusable Subsystem Outputs as Individual Arguments
The code generator eliminates data copies from local variables back to global block I/O structures by passing reusable subsystem outputs as individual arguments instead of as a pointer to a structure stored in global memory.
Enable and Reuse Local Block Outputs in Generated Code
Where possible, the code generator declares block outputs as local variables, so that it can potentially reuse these variables.

Data Copy Reduction by Specification

Optimize Generated Code by Using Signal Labels to Guide Buffer Reuse
Remove data copies by using signal labels.
Optimize Global Variable Usage
Choose a global variable reference optimization to satisfy your memory usage and execution speed requirements.
Specify Buffer Reuse for MATLAB Function Blocks in a Path
Reuse buffers across MATLAB Function blocks.
Specify Buffer Reuse for Signals in a Path
Use the Reusable storage class to specify buffer reuse for multiple signals in a path.
Generate Efficient Code for Buses
Model buses to maximize efficiency of the generated code.
Control Inlining to Fine-Tune Performance and Readability of Generated Code
Inlining eliminates the overhead of function calls but can produce larger C/C++ code and reduce code readability.