| |||

Home > NEON and VFP Programming > NEON general arithmetic instructions > VCLS, VCLZ, and VCNT |

`VCLS`

(Vector Count Leading Sign bits) counts
the number of consecutive bits following the topmost bit, that are
the same as the topmost bit, in each element in a vector, and places
the results in a second vector.

`VCLZ`

(Vector Count Leading Zeros) counts the
number of consecutive zeros, starting from the top bit, in each
element in a vector, and places the results in a second vector.

`VCNT`

(Vector Count set bits) counts the number
of bits that are one in each element in a vector, and places the
results in a second vector.

V{`op`

}.`cond`

`datatype`

,`Qd`

`Qm`

V{`op`

}.`cond`

`datatype`

,`Dd`

`Dm`

where:

`op`

must be one of

`CLS`

,`CLZ`

, or`CNT`

.`cond`

is an optional condition code.

`datatype`

must be one of:

`S8`

,`S16`

, or`S32`

for`CLS`

.`I8`

,`I16`

, or`I32`

for`CLZ`

.`I8`

for`CNT`

.

,`Qd`

`Qm`

are the destination vector and the operand vector, for a quadword operation.

,`Dd`

`Dm`

are the destination vector and the operand vector, for a doubleword operation.

- Reference