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[TSan] Add option to ignore capturing behavior when instrumenting #148156

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[TSan] Add option to ignore capturing behavior when instrumenting #148156

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7 changes: 6 additions & 1 deletion llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -80,6 +80,10 @@ static cl::opt<bool> ClCompoundReadBeforeWrite(
"tsan-compound-read-before-write", cl::init(false),
cl::desc("Emit special compound instrumentation for reads-before-writes"),
cl::Hidden);
static cl::opt<bool>
ClOmitNonCaptured("tsan-omit-by-pointer-capturing", cl::init(true),
cl::desc("Omit accesses due to pointer capturing"),
cl::Hidden);

STATISTIC(NumInstrumentedReads, "Number of instrumented reads");
STATISTIC(NumInstrumentedWrites, "Number of instrumented writes");
Expand Down Expand Up @@ -450,7 +454,8 @@ void ThreadSanitizer::chooseInstructionsToInstrument(

const AllocaInst *AI = findAllocaForValue(Addr);
// Instead of Addr, we should check whether its base pointer is captured.
if (AI && !PointerMayBeCaptured(AI, /*ReturnCaptures=*/true)) {
if (AI && !PointerMayBeCaptured(AI, /*ReturnCaptures=*/true) &&
ClOmitNonCaptured) {
// 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).
Expand Down