Some NEON instructions act on scalars in combination with
vectors. NEON scalars can be 8-bit, 16-bit, 32-bit, or 64-bit. Other
than multiply instructions, instructions that access scalars can
access any element in the register bank. The instruction syntax
refers to the scalars using an index into a doubleword vector, so
that Dm[x]xth element in 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 x
32-bit scalars are restricted to registers D0-D15,
with x
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