[PATCH] D52224: [Xray] llvm-xray fix possible segfault

[David CARLIER via Phabricator via llvm-commits]

devnexen created this revision.
devnexen added a reviewer: dberris.
devnexen created this object with visibility "All Users".
Herald added a subscriber: llvm-commits.

- top argument when superior to the instrumentated code list capacity can lead to a segfault.


Repository:
  rL LLVM

https://reviews.llvm.org/D52224

Files:
  tools/llvm-xray/xray-account.cpp


Index: tools/llvm-xray/xray-account.cpp
===================================================================
--- tools/llvm-xray/xray-account.cpp
+++ tools/llvm-xray/xray-account.cpp
@@ -358,8 +358,10 @@
     break;
   }
 
-  if (AccountTop > 0)
-    Results.erase(Results.begin() + AccountTop.getValue(), Results.end());
+  if (AccountTop > 0) {
+    auto MaxTop = std::min(AccountTop.getValue(), static_cast<int>(Results.end() - Results.begin()));
+    Results.erase(Results.begin() + MaxTop, Results.end());
+  }
 
   for (const auto &R : Results)
     Fn(std::get<0>(R), std::get<1>(R), std::get<2>(R));


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