nif.Cond = ir.NewBinaryExpr(base.Pos, ir.OLE, nuint, scapuint)
	nif.Likely = true

	// then { s = s[:newLen] }
	slice := ir.NewSliceExpr(base.Pos, ir.OSLICE, s, nil, newLen, nil)
	slice.SetBounded(true)
	nif.Body = []ir.Node{ir.NewAssignStmt(base.Pos, s, slice)}

	// else { s = growslice(oldPtr, newLen, oldCap, num, T) }
	call := walkGrowslice(s, nif.PtrInit(), oldPtr, newLen, oldCap, num)