According to Levicki:
Therefore, I have reverse-engineered Battlefield 2 game executable and come to the following conclusions:Loyd's blog entry/article goes on to detail what this means, what compiler optimizations are available, and theorizes about why game developers might or might not make full use of them. The optimizations specifically discussed are automated ones, not hand-coded, and should (in theory), be the sort of thing you flip on and use when compiling, with no additional headaches for the developer.
1. It was compiled using Visual Studio 2003 C++ compiler.
2. It was compiled in blended mode almost without any optimizations.
We've always known performance optimizations could dramatically boost Netburst performance; Intel pushed hard for the adoption of SSE2 after the Pentium 4 shipped in 2000 and invested a great deal of money in software and compiler development so programmers could take advantage of the chip's SIMD capability. It's surprising to hear that five years after launch, at least some major titles aren't compiled to perform optimally on modern chips that use SSE2.