51 lines
2.5 KiB
Ruby
51 lines
2.5 KiB
Ruby
module Virtual
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# This implements the creation of new frame and message object
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# Frames and Message are very similar apart from the class name
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# - All existing instances are stored in the space for both
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# - Size is currently 2, ie 16 words (TODO a little flexibility here would not hurt, but the mountain is big)
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# - Unused instances for a linked list with their first instance variable. This is HARD coded to avoid any lookup
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# Just as a reminder: a message object is created before a send and holds return address/message and arguemnts + self
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# frames are created upon entering a method and hold local and temporary variables
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# as a result one of each is created for every single method call. A LOT, so make it fast luke
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# Note: this is off course the reason for stack based implementations that just increment a known pointer/register or
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# something. But i think most programs are memory bound and a few extra instructions don't hurt.
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# After all, we are buying a big prize:oo, otherwise known as sanity.
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class FrameImplementation
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def run block
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block.codes.dup.each do |code|
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if code.is_a?(NewFrame)
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kind = :next_frame
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elsif code.is_a?(NewMessage)
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kind = :next_message
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else
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next
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end
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space = BootSpace.space
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slot = Virtual::Slot
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# a place to store a reference to the space, we grab the next_frame from the space
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space_tmp = Register::RegisterReference.new(Virtual::Message::TMP_REG)
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# a temporary place to store the new frame
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frame_tmp = space_tmp.next_reg_use
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# move the spave to it's register (mov instruction gets the address of the object)
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new_codes = [ Register::RegisterTransfer.new( space_tmp , space )]
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# find index in the space wehre to grab frame/message
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ind = space.layout[:names].index(kind)
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raise "index not found for :#{kind}" unless ind
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# load the frame/message from space by index
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new_codes << Register::GetSlot.new( frame_tmp , space_tmp , 5 )
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# save the frame in real frame register
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new_codes << Register::RegisterTransfer.new( Virtual::Message::FRAME_REG , frame_tmp )
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# get the next_frame
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new_codes << Register::GetSlot.new( frame_tmp , frame_tmp , 2 ) # 2 index of next_frame
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# save next frame into space
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new_codes << Register::SetSlot.new( frame_tmp , space_tmp , ind)
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block.replace(code , new_codes )
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end
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end
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end
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Virtual::BootSpace.space.add_pass "Virtual::FrameImplementation"
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end
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