[llvm-commits] [llvm] r73617 - /llvm/trunk/lib/VMCore/Type.cpp

[Owen Anderson]

Author: resistor
Date: Wed Jun 17 12:13:54 2009
New Revision: 73617

URL: http://llvm.org/viewvc/llvm-project?rev=73617&view=rev
Log:
We need to guard reads of the AbstractTypeUsers list, as well as writes to it.  While it would be nice to use a R/W lock here,
we can't, because it HAS to be recursive.

Modified:
    llvm/trunk/lib/VMCore/Type.cpp

Modified: llvm/trunk/lib/VMCore/Type.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/VMCore/Type.cpp?rev=73617&r1=73616&r2=73617&view=diff

==============================================================================
--- llvm/trunk/lib/VMCore/Type.cpp (original)
+++ llvm/trunk/lib/VMCore/Type.cpp Wed Jun 17 12:13:54 2009
@@ -46,7 +46,7 @@
 // Reader/writer lock used for guarding access to the type maps.
 static ManagedStatic<sys::RWMutex> TypeMapLock;
 
-// Lock used for guarding access to AbstractTypeUsers.
+// Recursive lock used for guarding access to AbstractTypeUsers.
 static ManagedStatic<sys::Mutex> AbstractTypeUsersLock;
 
 // Concrete/Abstract TypeDescriptions - We lazily calculate type descriptions
@@ -1544,6 +1544,7 @@
   // will not cause users to drop off of the use list.  If we resolve to ourself
   // we succeed!
   //
+  if (llvm_is_multithreaded()) AbstractTypeUsersLock->acquire();
   while (!AbstractTypeUsers.empty() && NewTy != this) {
     AbstractTypeUser *User = AbstractTypeUsers.back();
 
@@ -1559,6 +1560,7 @@
     assert(AbstractTypeUsers.size() != OldSize &&
            "AbsTyUser did not remove self from user list!");
   }
+  if (llvm_is_multithreaded()) AbstractTypeUsersLock->release();
 
   // If we were successful removing all users from the type, 'this' will be
   // deleted when the last PATypeHolder is destroyed or updated from this type.
@@ -1589,6 +1591,7 @@
   DOUT << "typeIsREFINED type: " << (void*)this << " " << *this << "\n";
 #endif
 
+  if (llvm_is_multithreaded()) AbstractTypeUsersLock->acquire();
   unsigned OldSize = AbstractTypeUsers.size(); OldSize=OldSize;
   while (!AbstractTypeUsers.empty()) {
     AbstractTypeUser *ATU = AbstractTypeUsers.back();
@@ -1597,6 +1600,7 @@
     assert(AbstractTypeUsers.size() < OldSize-- &&
            "AbstractTypeUser did not remove itself from the use list!");
   }
+  if (llvm_is_multithreaded()) AbstractTypeUsersLock->release();
 }
 
 // refineAbstractType - Called when a contained type is found to be more