Partial dead code elimination
Partial dead code elimination
复制标题
部分死代码消除
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
B. Steffen
中科院分区：
文献类型：
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作者：
J. Knoop;Oliver Rüthing;B. Steffen
提出了一种新的主动消除部分死码的算法，只在某些程序路径上死的代码。除了比通常的死代码消除方法更强大之外，该算法在以下意义上是最优的：在不改变程序的分支结构或语义的情况下，或者在不损害某些程序执行的情况下，无法消除结果程序中剩余的部分死代码。
我们的方法是基于部分冗余消除技术。除了一些新的技术问题，这里有一个显着的区别：部分死码消除引入二阶效应，我们克服了穷举运动和消除步骤。通过一种新的技术，这是普遍适用的，特别是在相互依赖的程序优化的情况下有用的，得到的程序的最优性和唯一性证明。
A new aggressive algorithm for the elimination of partially dead code is presented, i.e., of code which is only dead on some program paths. Besides being more powerful than the usual approaches to dead code elimination, this algorithm is optimal in the following sense: partially dead code remaining in the resulting program cannot be eliminated without changing the branching structure or the semantics of the program, or without impairing some program executions.
Our approach is based on techniques for partial redundancy elimination. Besides some new technical problems there is a significant difference here: partial dead code elimination introduces second order effects, which we overcome by means of exhaustive motion and elimination steps. The optimality and the uniqueness of the program obtained is proved by means of a new technique which is universally applicable and particularly useful in the case of mutually interdependent program optimizations.