Implement Tarjan's strongly-connected components algorithm #11239
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This commit implements [Tarjan's algorithm] for finding strongly-connected components. This algorithm takes `O(V+E)` time and uses `O(V+E)` space. Tarjan's algorithm is usually presented as a recursive algorithm, but we do not trust the input and cannot recurse over it for fear of blowing the stack. Therefore, this implementation is iterative. This will be used to do bottom-up inlining in Wasmtime's compilation orchestration. [Tarjan's algorithm]: https://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm
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I'm feeling a bit overwhelmed recently so I'm going to re-roll review. |
alexcrichton
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(I'm happy to cover this one as a "core compiler algorithms PR" unless you really want it, Andrew!) |
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Go for it! |
cfallin
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Very nice! A few thoughts below but overall LGTM.
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…lliance#11239) * Implement Tarjan's strongly-connected components algorithm This commit implements [Tarjan's algorithm] for finding strongly-connected components. This algorithm takes `O(V+E)` time and uses `O(V+E)` space. Tarjan's algorithm is usually presented as a recursive algorithm, but we do not trust the input and cannot recurse over it for fear of blowing the stack. Therefore, this implementation is iterative. This will be used to do bottom-up inlining in Wasmtime's compilation orchestration. [Tarjan's algorithm]: https://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm * address review feedback
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This commit implements Tarjan's algorithm for finding strongly-connected components.
This algorithm takes
O(V+E)time and usesO(V+E)space.Tarjan's algorithm is usually presented as a recursive algorithm, but we do not trust the input and cannot recurse over it for fear of blowing the stack. Therefore, this implementation is iterative.
This will be used to do bottom-up inlining in Wasmtime's compilation orchestration.