Some NEON instructions act on scalars in combination with
vectors. NEON scalars can be 8-bit, 16-bit, 32-bit, or 64-bit. The
instruction syntax refers to the scalars using an index, x,
into a doubleword vector, so that Dm[x]xth element in vector Dm
Multiply instructions only allow 16-bit or 32-bit scalars, and can only access the first 32 scalars in the register bank. That is, in multiply instructions:
16-bit scalars are restricted to registers D0-D7, with
x32-bit scalars are restricted to registers D0-D15, with
x
See also
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