EIP-7939

Count leading zeros (CLZ) opcode

Opcode to count the number of leading zero bits in a 256-bit word

Introduce a new opcode, CLZ(x), which pops x from the stack and pushes the number of leading zero bits in x to the stack. If x is zero, pushes 256.

Created

28 Apr 2025

Authors

Vectorized, Georgios Konstantopoulos, Jochem Brouwer, Ben Adams, Giulio Rebuffo

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