部分静的単一情報形式（Partial SSI）
静的単一情報形式（SSI）はSSAを拡張し、条件分岐から得られる型情報をIRノードとして明示する手法。本記事では、フルSSIの複雑なアルゴリズムを実装せずとも、SSA構築時や最適化中に部分的なSSIを導入する実用的な方法を解説。ZJITやCinder、TruffleRubyなど実際のコンパイラでの応用例も紹介する。
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