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VCLZ

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

The operand vector elements can be any one of 8-bit, 16-bit, or 32-bit integers. There is no distinction between signed and unsigned integers.

The result vector elements are the same data type as the operand vector elements.

Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be UNDEFINED, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

Decode for all variants of this encoding

if size == '11' then Undefined(); end; if Q == '1' && (Vd[0] == '1' || Vm[0] == '1') then Undefined(); end; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2;

T1

Decode for all variants of this encoding

if size == '11' then Undefined(); end; if Q == '1' && (Vd[0] == '1' || Vm[0] == '1') then Undefined(); end; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2;