Population count
The popcnt instructions, short for population count, are used to count the amount of 1s in a numbers binary representation.
Syntax
;; load a number onto the stack
i32.const 130 ;; 10000010
;; count the 1s
i32.popcnt
;; the top item on the stack will now be 2
| Instruction | Binary opcode | 
|---|---|
| i32.popcnt | 0x69 | 
| i64.popcnt | 0x7b |