Improve Regex's FindPrefixes handling for loops #98880
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We can factor in up to the minimum iteration count of the loop. This also makes handling a top-level alternation a bit cheaper.
ghost
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Tagging subscribers to this area: @dotnet/area-system-text-regularexpressions Issue DetailsWe can factor in up to the minimum iteration count of the loop. This also makes handling a top-level alternation a bit cheaper.
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src/libraries/System.Text.RegularExpressions/tests/UnitTests/RegexPrefixAnalyzerTests.cs
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Possible improvements from this change: |
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Nice. For dotnet/perf-autofiling-issues#29823 it seems there was an earlier regression that this unrelated improvement has canceled. Did we track that regression? Perhaps it was by design - I remember some regression due to correctness. |
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While improving something is always nice, I don't think this PR could have improved those tests. Many of them don't use regex, and the ones that do, the pattern they use shouldn't have been impacted by this change. |
We can factor in up to the minimum iteration count of the loop.
This also makes handling a top-level alternation a bit cheaper.