ARM > Efficient C for ARM > Floating Point

by David Thomas on —

Floating Point

Floating Point is usually emulated on ARM systems.

  • Slow.
    • 50-300× slower than equivalent integer ops.
    • Depending on library, environment.

Possible solution:

  • Fixed point maths.
    • Requires more thought.
    • Consequently more error prone.

Remarks

Is this the most fundamental thing?

Floating point is therefore slow and should be avoided unless you’re dealing with one special case. This applies even to Java.

http://en.wikibooks.org/wiki/Embedded_Systems/Embedded_System_Basics/Fixed-Point_Arithmetic