30.6.1. ARM VFP
The name for the ARMv7 and AArch32 floating point and SIMD instructions / registers.
Vector Floating Point extension.
TODO I think it was optional in ARMv7, find quote.
VFP has several revisions, named as VFPv1, VFPv2, etc. TODO: announcement dates.
As mentioned at: https://stackoverflow.com/questions/37790029/what-is-difference-between-arm64-and-armhf/48954012#48954012 the Linux kernel shows those capabilities in /proc/cpuinfo with flags such as vfp, vfpv3 and others, see:
When a certain version of VFP is present on a CPU, the compiler prefix typically contains the hf characters which stands for Hard Float, e.g.: arm-linux-gnueabihf. This means that the compiler will emit VFP instructions instead of just using software implementations.
Bibliography:
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ARMv7 architecture reference manual Appendix D6 "Common VFP Subarchitecture Specification". It is not part of the ISA, but just an extension. TODO: that spec does not seem to have the instructions documented, and instruction like VMOV just live with the main instructions. Is VMOV part of VFP?
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https://mindplusplus.wordpress.com/2013/06/25/arm-vfp-vector-programming-part-1-introduction/
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https://en.wikipedia.org/wiki/ARM_architecture#Floating-point_(VFP)