73 lines
1.7 KiB
Ruby
73 lines
1.7 KiB
Ruby
module Virtual
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# the virtual machine is implemented in values (a c++ version of oo).
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# Values have types which are represented as classes, instances of Type to be precise
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# Values must really be Constants or Variables, ie have a storage space
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class Value
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def == other
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other.class == self.class
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end
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def type
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raise "abstract called for #{self.class}"
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end
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def attributes
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raise "abstract called for #{self.class}"
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end
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def == other
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return false unless other.class == self.class
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attributes.each do |a|
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left = send(a)
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right = other.send(a)
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return false unless left.class == right.class
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return false unless left == right
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end
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return true
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end
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def inspect
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self.class.name + ".new(" + attributes.collect{|a| send(a).inspect }.join(",")+ ")"
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end
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private
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def initialize
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end
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end
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class Variable < Value
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def initialize name , type
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@name = name.to_sym
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@type = type
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end
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attr_accessor :name , :type
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def attributes
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[:name , :type]
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end
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end
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# The subclasses are not strictly speaking neccessary at this def point
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# i just don't want to destroy the information for later optimizations
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#
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# All variables are stored in frames and quite possibly in order arg,local,tmp
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class Return < Variable
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def initialize type
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super(:return , type)
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end
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def attributes
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[:type]
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end
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end
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class Self < Variable
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def initialize type
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super(:self , type)
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end
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def attributes
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[:type]
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end
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end
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class Argument < Variable
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end
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class Local < Variable
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end
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class Temp < Variable
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end
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end |