Make DataLayout Non-Optional in the Module

[oota-llvm.git] / lib / Transforms / Instrumentation / ThreadSanitizer.cpp

diff --git a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index e9999c486fad1e7774190364e30799dd6361f2f2..6b50ce9513b694785cfd4b2ac412b1b24170076f 100644 (file)
--- a/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -19,6 +19,8 @@
 // The rest is handled by the run-time library.
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Analysis/CaptureTracking.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/Transforms/Instrumentation.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/SmallString.h"
@@ -68,6 +70,7 @@ STATISTIC(NumInstrumentedVtableReads, "Number of vtable ptr reads");
 STATISTIC(NumOmittedReadsFromConstantGlobals,
           "Number of reads from constant globals");
 STATISTIC(NumOmittedReadsFromVtable, "Number of vtable reads");
+STATISTIC(NumOmittedNonCaptured, "Number of accesses ignored due to capturing");
 
 namespace {
 
@@ -227,10 +230,7 @@ void ThreadSanitizer::initializeCallbacks(Module &M) {
 }
 
 bool ThreadSanitizer::doInitialization(Module &M) {
-  DataLayoutPass *DLP = getAnalysisIfAvailable<DataLayoutPass>();
-  if (!DLP)
-    report_fatal_error("data layout missing");
-  DL = &DLP->getDataLayout();
+  DL = &M.getDataLayout();
 
   // Always insert a call to __tsan_init into the module's CTORs.
   IRBuilder<> IRB(M.getContext());
@@ -272,6 +272,7 @@ bool ThreadSanitizer::addrPointsToConstantData(Value *Addr) {
 // Instrumenting some of the accesses may be proven redundant.
 // Currently handled:
 //  - read-before-write (within same BB, no calls between)
+//  - not captured variables
 //
 // We do not handle some of the patterns that should not survive
 // after the classic compiler optimizations.
@@ -303,6 +304,17 @@ void ThreadSanitizer::chooseInstructionsToInstrument(
         continue;
       }
     }
+    Value *Addr = isa<StoreInst>(*I)
+        ? cast<StoreInst>(I)->getPointerOperand()
+        : cast<LoadInst>(I)->getPointerOperand();
+    if (isa<AllocaInst>(GetUnderlyingObject(Addr, nullptr)) &&
+        !PointerMayBeCaptured(Addr, true, true)) {
+      // The variable is addressable but not captured, so it cannot be
+      // referenced from a different thread and participate in a data race
+      // (see llvm/Analysis/CaptureTracking.h for details).
+      NumOmittedNonCaptured++;
+      continue;
+    }
     All.push_back(I);
   }
   Local.clear();