Tag Archives: x86

Exercises in Emulation: Xbox 360’s FMA Instruction

Years ago I worked in the Xbox 360 group at Microsoft. We were thinking about releasing a new console, and we thought it would be nice if that console could run the games of the previous console. Emulation is always … Continue reading

Posted in Floating Point | Tagged , , , , | 20 Comments

The Surprising Subtleties of Zeroing a Register

Zeroing out a CPU register seems like the simplest and most basic operation imaginable, but in fact x86 CPUs contain a surprising amount of special logic to make this operation run smoothly. The most obvious way of zeroing an x86 … Continue reading

Posted in Performance, Programming | Tagged , , , | 30 Comments