37 lines
956 B
Ruby
37 lines
956 B
Ruby
module Risc
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# name says it all really
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# only arg is the method syscall name
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# how the layer below executes these is really up to it
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# Any function issuing a Syscall should also save the current message
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# and restore it after the syscall, saving the return value in Return_index
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class Syscall < Instruction
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def initialize source ,name
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super(source)
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@name = name
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raise "must have name" unless name
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end
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attr_reader :name
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# return an array of names of registers that is used by the instruction
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def register_attributes
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[]
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end
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def to_s
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class_source name
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end
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end
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# return the nth register that a sycall needs
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# these map to different physical registers in the Platform
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# first arg is (running 1..) integer, second (optional) type
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def self.syscall_reg( number , type = nil)
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type = :Integer unless type
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RegisterValue.new("syscall_#{number}".to_sym , type)
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end
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end
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