[llvm-branch-commits] [BOLT] Name similarity function matching (PR #95884)

[via llvm-branch-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-bolt

Author: shaw young (shawbyoung)

<details>
<summary>Changes</summary>

Matching functions based on edit
distance.

Test Plan: tbd


---
Full diff: https://github.com/llvm/llvm-project/pull/95884.diff


1 Files Affected:

- (modified) bolt/lib/Profile/YAMLProfileReader.cpp (+29) 


``````````diff
diff --git a/bolt/lib/Profile/YAMLProfileReader.cpp b/bolt/lib/Profile/YAMLProfileReader.cpp
index f25f59201f1cd..a4f8ba9a440b6 100644
--- a/bolt/lib/Profile/YAMLProfileReader.cpp
+++ b/bolt/lib/Profile/YAMLProfileReader.cpp
@@ -13,6 +13,7 @@
 #include "bolt/Profile/ProfileYAMLMapping.h"
 #include "bolt/Utils/Utils.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/edit_distance.h"
 #include "llvm/Support/CommandLine.h"
 
 using namespace llvm;
@@ -23,6 +24,10 @@ extern cl::opt<unsigned> Verbosity;
 extern cl::OptionCategory BoltOptCategory;
 extern cl::opt<bool> InferStaleProfile;
 
+cl::opt<unsigned> NameSimilarityFunctionMatchingThreshold(
+    "name-similarity-function-matching-threshold", cl::desc("edit distance."),
+    cl::init(0), cl::Hidden, cl::cat(BoltOptCategory));
+
 static llvm::cl::opt<bool>
     IgnoreHash("profile-ignore-hash",
                cl::desc("ignore hash while reading function profile"),
@@ -415,6 +420,30 @@ Error YAMLProfileReader::readProfile(BinaryContext &BC) {
     if (!YamlBF.Used && BF && !ProfiledFunctions.count(BF))
       matchProfileToFunction(YamlBF, *BF);
 
+  // Uses name similarity to match functions that were not matched by name.
+  for (auto YamlBF : YamlBP.Functions) {
+    if (YamlBF.Used)
+      continue;
+
+    unsigned MinEditDistance = UINT_MAX;
+    BinaryFunction *ClosestNameBF = nullptr;
+
+    for (auto &[_, BF] : BC.getBinaryFunctions()) {
+      if (ProfiledFunctions.count(&BF))
+        continue;
+
+      unsigned BFEditDistance = BF.getOneName().edit_distance(YamlBF.Name);
+      if (BFEditDistance < MinEditDistance) {
+        MinEditDistance = BFEditDistance;
+        ClosestNameBF = &BF;
+      }
+    }
+
+    if (ClosestNameBF &&
+      MinEditDistance < opts::NameSimilarityFunctionMatchingThreshold)
+      matchProfileToFunction(YamlBF, *ClosestNameBF);
+  }
+
   for (yaml::bolt::BinaryFunctionProfile &YamlBF : YamlBP.Functions)
     if (!YamlBF.Used && opts::Verbosity >= 1)
       errs() << "BOLT-WARNING: profile ignored for function " << YamlBF.Name

``````````

</details>


https://github.com/llvm/llvm-project/pull/95884