HI,why the VFP vector mode can not be used in cortex-a series processors?

The short vector mode for VFP was removed in ARMv7 architecture, so it simply doesn't exist in Cortex-A (or other ARMv7 processors). However note that you gain the NEON SIMD instruction set, which is a true vector processing ISA.

Cheers,
Pete

The short vector mode for VFP was removed in ARMv7 architecture, so it simply doesn't exist in Cortex-A (or other ARMv7 processors). However note that you gain the NEON SIMD instruction set, which is a true vector processing ISA.

Cheers,
Pete