When compiling code with the GNU Compiler Collection (GCC), you can use the -fsave-optimization-record flag to save the optimization record to a file. The optimization record contains information about the optimizations performed on the code during the compilation process. This can be useful for analyzing and understanding the performance improvements achieved by the compiler.
How to Use -fsave-optimization-record Flag
To save the optimization record to a file, you need to add the -fsave-optimization-record flag when compiling your code with GCC. Here’s an example:
gcc -fsave-optimization-record input.c -o output
In the above command, replace input.c with the name of your source code file and output with the desired name for the compiled binary.
Retrieving the Optimization Record
Once you have compiled your code with the -fsave-optimization-record flag, GCC will generate an optimization record file with the extension .opt. This file contains detailed information about the optimizations performed during compilation.
To retrieve the optimization record, you can use the gcc-opt-viewer tool. This tool parses the optimization record file and presents the information in a readable format. You can install gcc-opt-viewer using the following command:
pip install gcc-opt-viewer
After installing gcc-opt-viewer, you can use the following command to view the optimization record:
gcc-opt-viewer filename.opt
Replace filename.opt with the name of your optimization record file.
Analyzing the Optimization Record
The optimization record provides valuable insights into the transformations applied to your code by the compiler. It includes information about the optimizations performed, such as loop unrolling, function inlining, and constant propagation. By analyzing this information, you can gain a better understanding of how the compiler is optimizing your code and identify any potential areas for further improvement.
Conclusion
The -fsave-optimization-record flag in GCC allows you to save the optimization record to a file, providing a detailed analysis of the optimizations performed on your code. By using the gcc-opt-viewer tool, you can easily retrieve and analyze the optimization record, gaining valuable insights into the compiler’s optimization strategies. This can help you optimize your code further and improve its performance.
References:
- GCC Optimization Options: https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html
- GCC Optimization Record Viewer: https://github.com/ulfjack/ryg_opt_view
#techblog #gcc