33 lines
1.0 KiB
Ruby
33 lines
1.0 KiB
Ruby
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module SlotMachine
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# SlotMachine internal check, as the name says to see if two values are the same
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# In other words, we this checks identity, bit-values, pointers
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#
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# The values that are compared are defined as Slots, ie can be anything
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# available to the machine through frame message or self
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#
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# Acording to SlotMachine::Check logic, we jump to the given label is the values are not the same
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#
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class SameCheck < Check
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attr_reader :left , :right
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def initialize(left, right , label)
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super(label)
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@left , @right = left , right
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end
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def to_s
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"SameCheck: #{left}:#{right}"
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end
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# basically move both left and right values into register
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# subtract them and see if IsZero comparison
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def to_risc(compiler)
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l_reg = left.to_register(compiler, self)
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r_reg = right.to_register(compiler, self)
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compiler.add_code Risc.op( self , :- , l_reg , r_reg)
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compiler.add_code Risc::IsNotZero.new( self, false_label.risc_label(compiler))
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end
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end
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end
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