From: Fangrui Song <maskray@google.com>
Date: Wed, 27 Mar 2019 09:38:05 +0000 (+0000)
Subject: [DWARF] Add D to Seen early to avoid duplicate elements in Worklist
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=650dceb82e23fc742651506ad3576930e9bd05e9;p=llvm

[DWARF] Add D to Seen early to avoid duplicate elements in Worklist

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@357054 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/DebugInfo/DWARF/DWARFDie.cpp b/lib/DebugInfo/DWARF/DWARFDie.cpp
index 4a837cd3526..3015ce2e94b 100644
--- a/lib/DebugInfo/DWARF/DWARFDie.cpp
+++ b/lib/DebugInfo/DWARF/DWARFDie.cpp
@@ -396,6 +396,7 @@ DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
   // DWARF. This corresponds to following the DW_AT_abstract_origin and
   // DW_AT_specification just once.
   SmallSet<DWARFDie, 3> Seen;
+  Seen.insert(*this);
 
   while (!Worklist.empty()) {
     DWARFDie Die = Worklist.back();
@@ -404,19 +405,16 @@ DWARFDie::findRecursively(ArrayRef<dwarf::Attribute> Attrs) const {
     if (!Die.isValid())
       continue;
 
-    if (Seen.count(Die))
-      continue;
-
-    Seen.insert(Die);
-
     if (auto Value = Die.find(Attrs))
       return Value;
 
     if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_abstract_origin))
-      Worklist.push_back(D);
+      if (Seen.insert(D).second)
+        Worklist.push_back(D);
 
     if (auto D = Die.getAttributeValueAsReferencedDie(DW_AT_specification))
-      Worklist.push_back(D);
+      if (Seen.insert(D).second)
+        Worklist.push_back(D);
   }
 
   return None;