Another interesting change for GCC 4 is the addition of a loop vectorizer (based on the Tree SSA framework).

GCC4 的另一个有趣的变化是增加了一个循环向量器（基于Tree SSA框架）。

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This release included a large number of changes-two in particular being the introduction of a new optimization framework (Tree SSA) and support for autovectorization.

这个发行版包含很多变化—其中两个特别的变化是引入了新的优化框架(Tree ssa)和支持自动向量化(autovectorization)。

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GCC 4 brings many changes to the standard compiler suite, the biggest of which is around support for optimizations with the introduction of the tree Static Single Assignment (SSA) form.

GCC4为标准的编译器套件带来了很多变化，最大的变化是为了支持优化而引入的树的StaticSingleAssignment (ssa)形式。

youdao

GCC 4 brings many changes to the standard compiler suite, the biggest of which is around support for optimizations with the introduction of the tree Static Single Assignment (SSA) form.

GCC4为标准的编译器套件带来了很多变化，最大的变化是为了支持优化而引入的树的StaticSingleAssignment (ssa)形式。

youdao