[SpecialCaseList] Filtering Globs with matching prefix #164531
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Created using spr 1.3.7 [skip ci]
Created using spr 1.3.7
|
@llvm/pr-subscribers-llvm-support Author: Vitaly Buka (vitalybuka) ChangesThis commit optimizes Full diff: https://github.com/llvm/llvm-project/pull/164531.diff 2 Files Affected:
diff --git a/llvm/include/llvm/Support/SpecialCaseList.h b/llvm/include/llvm/Support/SpecialCaseList.h
index ead765562504d..16f309329a0b5 100644
--- a/llvm/include/llvm/Support/SpecialCaseList.h
+++ b/llvm/include/llvm/Support/SpecialCaseList.h
@@ -13,10 +13,13 @@
#define LLVM_SUPPORT_SPECIALCASELIST_H
#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/iterator_range.h"
#include "llvm/Support/Allocator.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/GlobPattern.h"
+#include "llvm/Support/RadixTree.h"
#include "llvm/Support/Regex.h"
#include <memory>
#include <string>
@@ -162,6 +165,10 @@ class SpecialCaseList {
};
std::vector<GlobMatcher::Glob> Globs;
+
+ RadixTree<iterator_range<StringRef::const_iterator>,
+ SmallVector<const GlobMatcher::Glob *, 1>>
+ PrefixToGlob;
};
/// Represents a set of patterns and their line numbers
diff --git a/llvm/lib/Support/SpecialCaseList.cpp b/llvm/lib/Support/SpecialCaseList.cpp
index f74e52a3a7fa9..2a86cc37b6000 100644
--- a/llvm/lib/Support/SpecialCaseList.cpp
+++ b/llvm/lib/Support/SpecialCaseList.cpp
@@ -89,14 +89,28 @@ void SpecialCaseList::GlobMatcher::preprocess(bool BySize) {
return A.Name.size() < B.Name.size();
});
}
+
+ for (auto &G : Globs) {
+ StringRef Prefix = G.Pattern.prefix();
+
+ auto &V = PrefixToGlob.emplace(Prefix).first->second;
+ V.emplace_back(&G);
+ }
}
void SpecialCaseList::GlobMatcher::match(
StringRef Query,
llvm::function_ref<void(StringRef Rule, unsigned LineNo)> Cb) const {
- for (const auto &G : reverse(Globs))
- if (G.Pattern.match(Query))
- return Cb(G.Name, G.LineNo);
+ if (!PrefixToGlob.empty()) {
+ for (const auto &[_, V] : PrefixToGlob.find_prefixes(Query)) {
+ for (const auto *G : reverse(V)) {
+ if (G->Pattern.match(Query)) {
+ Cb(G->Name, G->LineNo);
+ break;
+ }
+ }
+ }
+ }
}
SpecialCaseList::Matcher::Matcher(bool UseGlobs, bool RemoveDotSlash)
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Created using spr 1.3.7 [skip ci]
Created using spr 1.3.7 [skip ci]
fmayer
approved these changes
Oct 23, 2025
Created using spr 1.3.7 [skip ci]
Created using spr 1.3.7 [skip ci]
vitalybuka
added a commit
that referenced
this pull request
Oct 25, 2025
This commit introduces a RadixTree implementation to LLVM. RadixTree, as a Trie, is very efficient by searching for prefixes. A Radix Tree is more efficient implementation of Trie. The tree will be used to optimize Glob matching in SpecialCaseList: * #164531 * #164543 * #164545 --------- Co-authored-by: Kazu Hirata <kazu@google.com> Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
llvm-sync bot
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Oct 25, 2025
This commit introduces a RadixTree implementation to LLVM. RadixTree, as a Trie, is very efficient by searching for prefixes. A Radix Tree is more efficient implementation of Trie. The tree will be used to optimize Glob matching in SpecialCaseList: * llvm/llvm-project#164531 * llvm/llvm-project#164543 * llvm/llvm-project#164545 --------- Co-authored-by: Kazu Hirata <kazu@google.com> Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
vitalybuka
changed the base branch from
users/vitalybuka/spr/main.specialcaselist-filtering-globs-with-matching-prefix
to
main
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Pull Request Overview
This PR optimizes SpecialCaseList by introducing a RadixTree-based prefix filtering mechanism for glob patterns. The optimization reduces the number of glob patterns that need full evaluation during matching by first filtering candidates based on their prefixes, achieving significant performance improvements (81.77% reduction for general lookups, 98.19% for prefix-pattern lookups).
Key Changes:
- Added
RadixTreeto index glob patterns by their prefixes during preprocessing - Modified the matching algorithm to use prefix-based filtering before glob evaluation
- Maintained sorting order within prefix groups to preserve best-to-worst matching priority
Reviewed Changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.
| File | Description |
|---|---|
| llvm/include/llvm/Support/SpecialCaseList.h | Added RadixTree member and necessary includes to support prefix-based glob filtering |
| llvm/lib/Support/SpecialCaseList.cpp | Implemented prefix indexing in preprocess() and updated match() to use the RadixTree for efficient pattern filtering |
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
vitalybuka
deleted the
users/vitalybuka/spr/specialcaselist-filtering-globs-with-matching-prefix
branch
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LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/138/builds/20915 Here is the relevant piece of the build log for the reference |
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This commit optimizes
SpecialCaseListby using aRadixTreeto filterglob patterns based on their prefixes. When matching a query, the
RadixTreequickly identifies all glob patterns whose prefixes matchthe query's prefix. This significantly reduces the number of glob
patterns that need to be fully evaluated, leading to performance
improvements, especially when dealing with a large number of patterns.
According to SpecialCaseListBM:
Lookup benchmarks (significant improvements):
Lookup like
prefix*benchmarks (huge improvements):https://gist.github.com/vitalybuka/824884bcbc1713e815068c279159dafe