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17 lines
617 B
17 lines
617 B
2 years ago
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Exercise 5.31: In evaluating a procedure
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application, the explicit-control evaluator always saves and restores the
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env register around the evaluation of the operator, saves and restores
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env around the evaluation of each operand (except the final one), saves
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and restores argl around the evaluation of each operand, and saves and
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restores proc around the evaluation of the operand sequence. For each
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of the following combinations, say which of these save and
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restore operations are superfluous and thus could be eliminated by the
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compiler’s preserving mechanism:
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(f 'x 'y)
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((f) 'x 'y)
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(f (g 'x) y)
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(f (g 'x) 'y)
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