Fix a subtle use-after-free issue.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110863 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/LazyValueInfo.cpp b/lib/Analysis/LazyValueInfo.cpp
index c932e81e2457764867ac765c800ee491cc02d1b6..d3a437f9405057ea4b8af7545c86756fd533f30e 100644 (file)
--- a/lib/Analysis/LazyValueInfo.cpp
+++ b/lib/Analysis/LazyValueInfo.cpp
@@ -384,7 +384,6 @@ namespace {
 } // end anonymous namespace
 
 void LazyValueInfoCache::LVIValueHandle::deleted() {
-  Parent->ValueCache.erase(*this);
   for (std::set<std::pair<BasicBlock*, Value*> >::iterator
        I = Parent->OverDefinedCache.begin(),
        E = Parent->OverDefinedCache.end();
@@ -394,6 +393,10 @@ void LazyValueInfoCache::LVIValueHandle::deleted() {
     if (tmp->second == getValPtr())
       Parent->OverDefinedCache.erase(tmp);
   }
+  
+  // This erasure deallocates *this, so it MUST happen after we're done
+  // using any and all members of *this.
+  Parent->ValueCache.erase(*this);
 }