# Linux Kernel Module Cheat

#### 29.11.1. x86 x87 FPU vs SIMD

https://stackoverflow.com/questions/1844669/benefits-of-x87-over-sse

Modern x86 has two main ways of doing floating point operations:

- x86 x87 FPU instructions

- x86 SIMD

Advantages of FPU:

- present in old CPUs, while SSE2 is only required in x86-64

- contains some instructions no present in SSE, e.g. trigonometric

- higher precision: FPU holds 80 bit Intel extension, while SSE2 only does up to 64 bit operations despite having the 128-bit register

In GCC, you can choose between them with `-mfpmath=`.