30 lines
876 B
Ruby
30 lines
876 B
Ruby
module Virtual
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module Compiler
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# while- attr_reader :condition, :body
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def self.compile_while expression, method
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# this is where the while ends and both branches meet
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merge = method.source.new_block("while merge")
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# this comes after the current and beofre the merge
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start = method.source.new_block("while_start" )
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method.source.current start
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cond = Compiler.compile(expression.condition, method)
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method.source.add_code IsTrueBranch.new(merge)
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last = cond
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expression.body.each do |part|
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last = Compiler.compile(part , method)
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raise part.inspect if last.nil?
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end
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# unconditionally branch to the start
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method.source.add_code UnconditionalBranch.new(start)
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# continue execution / compiling at the merge block
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method.source.current merge
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last
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end
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end
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end
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