CLS

Count leading sign bits: Rd = CLS(Rn).

313029282726252423222120191817161514131211109876543210
sf101101011000000000101RnRd
op

32-bit (sf == 0)

CLS <Wd>, <Wn>

64-bit (sf == 1)

CLS <Xd>, <Xn>

integer d = UInt(Rd); integer n = UInt(Rn); integer datasize = if sf == '1' then 64 else 32; CountOp opcode = if op == '0' then CountOp_CLZ else CountOp_CLS;

Assembler Symbols

<Wd>

Is the 32-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Wn>

Is the 32-bit name of the general-purpose source register, encoded in the "Rn" field.

<Xd>

Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Xn>

Is the 64-bit name of the general-purpose source register, encoded in the "Rn" field.

Operation

integer result; bits(datasize) operand1 = X[n]; if opcode == CountOp_CLZ then result = CountLeadingZeroBits(operand1); else result = CountLeadingSignBits(operand1); X[d] = result<datasize-1:0>;


Internal version only: isa v25.07, AdvSIMD v23.0, pseudocode v31.3

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