The ARM floating-point environment is an implementation of the IEEE 754 standard for binary floating-point arithmetic. See IEEE 754 arithmetic for details of the ARM implementation of the standard.

An ARM system might have:

If you compile for a system with a hardware coprocessor (VFP or FPA), the compilers make use of it. If you compile for a system without a coprocessor, the compilers implement the calculations in software.

For example, the compiler option -fpu vfp selects a hardware VFP coprocessor and the option -fpu softvfp selects coprocessor instructions are to be implemented in software.