2014-04-26 10:52:28 -04:00
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register dancing
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2014-04-26 11:54:15 -04:00
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n. Many older processor architectures suffer from a serious shortage of
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general-purpose registers. This is especially a problem for
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compiler-writers, because their generated code needs places to store
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temporaries for things like intermediate values in expression evaluation.
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Some designs with this problem, like the Intel 80x86, do have a handful of
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special-purpose registers that can be pressed into service, providing
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suitable care is taken to avoid unpleasant side effects on the state of the
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processor: while the special-purpose register is being used to hold an
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intermediate value, a delicate minuet is required in which the previous
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value of the register is saved and then restored just before the official
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function (and value) of the special-purpose register is again needed.
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