Firefox 3 with Profile-Guided Optimization = Speeding ticket
Hopefully the next Firefox 3 beta will be build with PGO.
So what is Profile Guided Optimization?
When building (compiling) Firefox, a set of tests are run and the data from these tests are used to optimize the compiled code. The data from the tests enables the compiler to aggressively optimize code in Firefox. The data represents how the program is likely to perform in a production environment. Basically, it runs the Firefox code to see what functions get used the most and optimizes the final code around that data.
Profile-guided optimization is a relatively new feature in both GCC and Visual C++ that improves the quality of generated code.
IE already doing this
IE7 was build with Profile-Guided Optimizations and gained a 8% performance improvement with no additional code change.
For more information about Profile-Guided Optimizations:
- Profile-Guided Optimizations in Microsoft Visual C++
- Building with Profile-Guided Optimization