fixnum-bit-count ( x -- n )

Vocabulary

math.bitwise.private

Inputs

x

an object

Outputs

n

an object

Definition

USING: combinators kernel kernel.private layouts math ;

IN: math.bitwise.private

: fixnum-bit-count ( x -- n )
    { fixnum } declare {
        [ byte-bit-count ]
        [ -8 shift byte-bit-count + ]
        [ -16 shift byte-bit-count + ]
        [ -24 shift byte-bit-count + ]
        [
            cell 8 = [
                {
                    [ -32 shift byte-bit-count + ]
                    [ -40 shift byte-bit-count + ]
                    [ -48 shift byte-bit-count + ]
                    [ -56 shift byte-bit-count + ]
                } cleave >fixnum
            ] [ drop ] if
        ]
    } cleave ;