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CLZ

Operation

Counts leading zero bits in the selected-width source and writes the count.

Assembler Syntax

CLZ.{B|W|L|Q}(z) <ea>(e), Rn(d)

CLZ.{B|W|L|Q}(z) Rn(s), Rn(d)

Privilege

Unprivileged

Repeat eligibility

REP eligible; REPcc observes dst

Counts the leading zero bits within the selected operand size and writes the count to the destination register. A zero operand returns the operand width in bits.

2.75in

Encodings

CLZ.{B|W|L|Q}(z) <ea>(e), Rn(d)

Format: Instruction format for CLZ.{B|W|L|Q}(z) <ea>(e), Rn(d)

Format: Instruction format for CLZ.{B|W|L|Q}(z) <ea>(e), Rn(d)

2.75in CLZ.{B|W|L|Q}(z) Rn(s), Rn(d)

Format: Instruction format for CLZ.{B|W|L|Q}(z) Rn(s), Rn(d)

Format: Instruction format for CLZ.{B|W|L|Q}(z) Rn(s), Rn(d)