52 lines
1.5 KiB
Ruby
52 lines
1.5 KiB
Ruby
module Ast
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class OperatorExpression < Expression
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attr_reader :operator, :left, :right
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def initialize operator, left, right
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@operator, @left, @right = operator, left, right
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end
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def attributes
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[:operator, :left, :right]
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end
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def inspect
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self.class.name + ".new(" + operator.inspect + ", " + left.inspect + "," + right.inspect + ")"
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end
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def to_s
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"#{left} #{operator} #{right}"
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end
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def compile context , into
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puts "compile operator #{to_s}"
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r_val = right.compile(context , into)
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if operator == "=" # assignment, value based
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raise "Can only assign variables, not #{left}" unless left.is_a?(NameExpression)
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l_val = context.locals[left.name]
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if( l_val ) #variable existed, move data there
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l_val = l_val.move( into , r_val)
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else
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if r_val.is_a? Vm::IntegerConstant
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next_register = context.function.next_register
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l_val = Vm::Integer.new(next_register).load( into , r_val )
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else
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l_val = r_val
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end
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end
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context.locals[left.name] = l_val
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return l_val
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end
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l_val = left.compile(context , into)
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case operator
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when ">"
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code = l_val.less_or_equal into , r_val
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when "+"
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code = l_val.plus into , r_val
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when "-"
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code = l_val.minus into , r_val
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else
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raise "unimplemented operator #{operator} #{self}"
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end
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end
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end
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end |