mirror of https://github.com/safiire/n65.git
56 lines
1.2 KiB
Ruby
56 lines
1.2 KiB
Ruby
require_relative '../instruction_base'
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module N65
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####
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## This directive to include bytes
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class EnterScope < InstructionBase
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####
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## Try to parse an incbin directive
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def self.parse(line)
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## Anonymous scope
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match_data = line.match(/^\.scope$/)
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unless match_data.nil?
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return EnterScope.new
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end
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## Named scope
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match_data = line.match(/^\.scope\s+([a-zA-Z][a-zA-Z0-9_]+)$/)
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return nil if match_data.nil?
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EnterScope.new(match_data[1])
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end
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####
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## Initialize with filename
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def initialize(name = nil)
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@name = name
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end
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####
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## Execute on the assembler, also create a symbol referring to
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## the current pc which contains a hyphen, and is impossible for
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## the user to create. This makes a scope simultaneously act as
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## a label to the current PC. If someone tries to use a scope
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## name as a label, it can return the address when the scope opened.
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def exec(assembler)
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assembler.symbol_table.enter_scope(@name)
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unless @name.nil?
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assembler.symbol_table.define_symbol("-#{@name}", assembler.program_counter)
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end
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end
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####
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## Display
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def to_s
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".scope #{@name}"
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end
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end
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end
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