Fix quadratic behavior when parsing inlines#378
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jgm merged 2 commits intocommonmark:masterfrom Mar 19, 2021
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The inline parsing code would call cmark_node_append_child to append nodes. This public function has a sanity check which is linear in the depth of the tree. Repeated calls could show quadratic behavior in degenerate trees. Use a special function to append nodes without this check. Fixes commonmark#373. Found by OSS-Fuzz.
Skip hierarchy check in the common case that the inserted child has no children.
jgm
reviewed
Mar 18, 2021
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| // Verify that child is not an ancestor of node or equal to node. |
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I can see why, if child has no children, it cannot be an ancestor of node.
But what is replacing the check to verify that child is not equal to node?
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The equality test is now a few lines above.
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Sorry it took me a while to look at this. It looks great. |
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I didn't measure anything, but the changes should also speed up parsing real-world documents. |
Member
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Excellent. |
Member
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I ran the benchmarks and it does look like we get a small speedup (~2-3%). |
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The inline parsing code would call cmark_node_append_child to append
nodes. This public function has a sanity check which is linear in the
depth of the tree. Repeated calls could show quadratic behavior in
degenerate trees. Use a special function to append nodes without this
check.
Fixes #373. Found by OSS-Fuzz.