In VFPv3 and VFPv3-FP16, you can view the extension register bank as:
Thirty-two 64-bit registers,
D0-D31.Thirty-two 32-bit registers,
S0-S31. Only half of the register bank is accessible in this view.A combination of registers from the above views.
In VFPv2, VFPv3-D16, and VFPv3-D16-FP16, you can view the extension register bank as:
Sixteen 64-bit registers,
D0-D15.Thirty-two 32-bit registers,
S0-S31.A combination of registers from the above views.
In VFP, 64-bit registers are called double-precision registers and can contain double-precision floating-point values. 32-bit registers are called single-precision registers and can contain either a single-precision or two half-precision floating-point values.
See also
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