rubyx/lib/register/instructions/label.rb
2017-01-04 21:32:09 +02:00

86 lines
1.8 KiB
Ruby

module Register
# A label is a placeholder for it's next Instruction
# It's function is not to turn into code, but to be a valid brnch target
#
# So branches and Labels are pairs, fan out, fan in
#
#
class Label < Instruction
def initialize( source , name , nekst = nil)
super(source , nekst)
@name = name
end
attr_reader :name
def to_s
"Label: #{@name} (#{self.next.class.name.split("::").last})"
end
def sof_reference_name
@name
end
# a method start has a label of the form Class.method , test for that
def is_method
@name.split(".").length == 2
end
def to_arr labels = []
return [] if labels.include?(self)
labels << self
super
end
def length labels = []
return 0 if labels.include?(self)
labels << self
ret = 1
ret += self.next.length(labels) if self.next
ret
end
def assemble io
end
def assemble_all io , labels = []
return if labels.include?(self)
labels << self
self.next.assemble_all(io,labels)
end
def total_byte_length labels = []
return 0 if labels.include?(self)
labels << self
ret = self.next.total_byte_length(labels)
#puts "#{self.class.name} return #{ret}"
ret
end
# labels have the same position as their next
def set_position position , labels = []
return position if labels.include?(self)
labels << self
super(position , labels)
self.next.set_position(position,labels)
end
# shame we need this, just for logging
def byte_length
0
end
def each_label labels =[] , &block
return if labels.include?(self)
labels << self
block.yield(self)
super
end
end
def self.label( source , name , nekst = nil)
Label.new( source , name , nekst = nil)
end
end