commit ab78ac1a2d55cd81e42f4688fbaa7bd689e6291f
author Dmitry Vyukov <dvyukov@google.com> Fri Mar 22 08:51:22 2013 +0000
committer Dmitry Vyukov <dvyukov@google.com> Fri Mar 22 08:51:22 2013 +0000
tree 7a281667154aab04e6fccc4ec787c725722a3d54
parent 7541cd36fdd1bd044e22497838faac7b8f7e48cd

tsan: handle vptr loads specially
This is required to determine ctor/dtor vs virtual call races.
http://llvm-reviews.chandlerc.com/D566



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177717 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Instrumentation/ThreadSanitizer.cpp

diff --git a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index f93c5ab..40e0908 100644
--- a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -63,6 +63,7 @@
           "Number of reads ignored due to following writes");
 STATISTIC(NumAccessesWithBadSize, "Number of accesses with bad size");
 STATISTIC(NumInstrumentedVtableWrites, "Number of vtable ptr writes");
+STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads");
 STATISTIC(NumOmittedReadsFromConstantGlobals,
           "Number of reads from constant globals");
 STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads");
@@ -108,6 +109,7 @@
   Function *TsanAtomicThreadFence;
   Function *TsanAtomicSignalFence;
   Function *TsanVptrUpdate;
+  Function *TsanVptrLoad;
 };
 }  // namespace
 
@@ -196,6 +198,8 @@
   TsanVptrUpdate = checkInterfaceFunction(M.getOrInsertFunction(
       "__tsan_vptr_update", IRB.getVoidTy(), IRB.getInt8PtrTy(),
       IRB.getInt8PtrTy(), NULL));
+  TsanVptrLoad = checkInterfaceFunction(M.getOrInsertFunction(
+      "__tsan_vptr_read", IRB.getVoidTy(), IRB.getInt8PtrTy(), NULL));
   TsanAtomicThreadFence = checkInterfaceFunction(M.getOrInsertFunction(
       "__tsan_atomic_thread_fence", IRB.getVoidTy(), OrdTy, NULL));
   TsanAtomicSignalFence = checkInterfaceFunction(M.getOrInsertFunction(
@@ -386,6 +390,12 @@
     NumInstrumentedVtableWrites++;
     return true;
   }
+  if (!IsWrite && isVtableAccess(I)) {
+    IRB.CreateCall(TsanVptrLoad,
+                   IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
+    NumInstrumentedVtableReads++;
+    return true;
+  }
   Value *OnAccessFunc = IsWrite ? TsanWrite[Idx] : TsanRead[Idx];
   IRB.CreateCall(OnAccessFunc, IRB.CreatePointerCast(Addr, IRB.getInt8PtrTy()));
   if (IsWrite) NumInstrumentedWrites++;