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20 lines
501 B
20 lines
501 B
3 years ago
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Exercise 5.8: The following register-machine code
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is ambiguous, because the label here is defined more than once:
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start
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(goto (label here))
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here
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(assign a (const 3))
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(goto (label there))
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here
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(assign a (const 4))
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(goto (label there))
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there
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With the simulator as written, what will the contents of register a be
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when control reaches there? Modify the extract-labels procedure
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so that the assembler will signal an error if the same label name is used to
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indicate two different locations.
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