bit.sub

dst[:n] -= src[:n]
dst,src are bit[:n]

Signature

def sub n, dst, src @ carry { ... }

Defined in bit/math.fj — lines 91–99 (view on GitHub).

Complexity

• Time: n(8@+16)

• Space: n(8@+16)

See the complexity glossary for what @, w, dw, dbit, n mean.

Source

Click to view the macro body

def sub n, dst, src @ carry {
    .not n, src
    .one carry
    rep(n, i) .add1 dst+i*dw, src+i*dw, carry
    .not n, src
    stl.skip
  carry:
    .bit
}

Depends on

• bit.bit/0

• bit.not/2

• bit.one/1

• stl.skip

Used by

• bit.div.div_step

• bit.div_loop

Example uses

• bit.div.div_step in bit/div.fj

• bit.div_loop in bit/div.fj

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