[NewPM][TSan] Reiterate the TSan port

Summary:
Second iteration of D56433 which got reverted in rL350719. The problem
in the previous version was that we dropped the thunk calling the tsan init
function. The new version keeps the thunk which should appease dyld, but is not
actually OK wrt. the current semantics of function passes. Hence, add a
helper to insert the functions only on the first time. The helper
allows hooking into the insertion to be able to append them to the
global ctors list.

Reviewers: chandlerc, vitalybuka, fedor.sergeev, leonardchan

Subscribers: hiraditya, bollu, llvm-commits

Differential Revision: https://reviews.llvm.org/D56538

llvm-svn: 351314

1 files changed, 63 insertions, 34 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
index fa1e5a157a0..077364e15c4 100644
--- a/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/ThreadSanitizer.cpp
@@ -19,6 +19,7 @@
 // The rest is handled by the run-time library.
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Transforms/Instrumentation/ThreadSanitizer.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/SmallVector.h"
@@ -86,15 +87,16 @@ static const char *const kTsanInitName = "__tsan_init";
 namespace {
 
 /// ThreadSanitizer: instrument the code in module to find races.
-struct ThreadSanitizer : public FunctionPass {
-  ThreadSanitizer() : FunctionPass(ID) {}
-  StringRef getPassName() const override;
-  void getAnalysisUsage(AnalysisUsage &AU) const override;
-  bool runOnFunction(Function &F) override;
-  bool doInitialization(Module &M) override;
-  static char ID;  // Pass identification, replacement for typeid.
-
- private:
+///
+/// Instantiating ThreadSanitizer inserts the tsan runtime library API function
+/// declarations into the module if they don't exist already. Instantiating
+/// ensures the __tsan_init function is in the list of global constructors for
+/// the module.
+struct ThreadSanitizer {
+  ThreadSanitizer(Module &M);
+  bool sanitizeFunction(Function &F, const TargetLibraryInfo &TLI);
+
+private:
   void initializeCallbacks(Module &M);
   bool instrumentLoadOrStore(Instruction *I, const DataLayout &DL);
   bool instrumentAtomic(Instruction *I, const DataLayout &DL);
@@ -130,27 +132,55 @@ struct ThreadSanitizer : public FunctionPass {
   Function *MemmoveFn, *MemcpyFn, *MemsetFn;
   Function *TsanCtorFunction;
 };
+
+struct ThreadSanitizerLegacyPass : FunctionPass {
+  ThreadSanitizerLegacyPass() : FunctionPass(ID) {}
+  StringRef getPassName() const override;
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+  bool runOnFunction(Function &F) override;
+  bool doInitialization(Module &M) override;
+  static char ID; // Pass identification, replacement for typeid.
+private:
+  Optional<ThreadSanitizer> TSan;
+};
 }  // namespace
 
-char ThreadSanitizer::ID = 0;
-INITIALIZE_PASS_BEGIN(
-    ThreadSanitizer, "tsan",
-    "ThreadSanitizer: detects data races.",
-    false, false)
+PreservedAnalyses ThreadSanitizerPass::run(Function &F,
+                                           FunctionAnalysisManager &FAM) {
+  ThreadSanitizer TSan(*F.getParent());
+  if (TSan.sanitizeFunction(F, FAM.getResult<TargetLibraryAnalysis>(F)))
+    return PreservedAnalyses::none();
+  return PreservedAnalyses::all();
+}
+
+char ThreadSanitizerLegacyPass::ID = 0;
+INITIALIZE_PASS_BEGIN(ThreadSanitizerLegacyPass, "tsan",
+                      "ThreadSanitizer: detects data races.", false, false)
 INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
-INITIALIZE_PASS_END(
-    ThreadSanitizer, "tsan",
-    "ThreadSanitizer: detects data races.",
-    false, false)
+INITIALIZE_PASS_END(ThreadSanitizerLegacyPass, "tsan",
+                    "ThreadSanitizer: detects data races.", false, false)
 
-StringRef ThreadSanitizer::getPassName() const { return "ThreadSanitizer"; }
+StringRef ThreadSanitizerLegacyPass::getPassName() const {
+  return "ThreadSanitizerLegacyPass";
+}
 
-void ThreadSanitizer::getAnalysisUsage(AnalysisUsage &AU) const {
+void ThreadSanitizerLegacyPass::getAnalysisUsage(AnalysisUsage &AU) const {
   AU.addRequired<TargetLibraryInfoWrapperPass>();
 }
 
-FunctionPass *llvm::createThreadSanitizerPass() {
-  return new ThreadSanitizer();
+bool ThreadSanitizerLegacyPass::doInitialization(Module &M) {
+  TSan.emplace(M);
+  return true;
+}
+
+bool ThreadSanitizerLegacyPass::runOnFunction(Function &F) {
+  auto &TLI = getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
+  TSan->sanitizeFunction(F, TLI);
+  return true;
+}
+
+FunctionPass *llvm::createThreadSanitizerLegacyPassPass() {
+  return new ThreadSanitizerLegacyPass();
 }
 
 void ThreadSanitizer::initializeCallbacks(Module &M) {
@@ -252,16 +282,16 @@ void ThreadSanitizer::initializeCallbacks(Module &M) {
                             IRB.getInt32Ty(), IntptrTy));
 }
 
-bool ThreadSanitizer::doInitialization(Module &M) {
+ThreadSanitizer::ThreadSanitizer(Module &M) {
   const DataLayout &DL = M.getDataLayout();
   IntptrTy = DL.getIntPtrType(M.getContext());
-  std::tie(TsanCtorFunction, std::ignore) = createSanitizerCtorAndInitFunctions(
-      M, kTsanModuleCtorName, kTsanInitName, /*InitArgTypes=*/{},
-      /*InitArgs=*/{});
-
-  appendToGlobalCtors(M, TsanCtorFunction, 0);
-
-  return true;
+  std::tie(TsanCtorFunction, std::ignore) =
+      getOrCreateSanitizerCtorAndInitFunctions(
+          M, kTsanModuleCtorName, kTsanInitName, /*InitArgTypes=*/{},
+          /*InitArgs=*/{},
+          // This callback is invoked when the functions are created the first
+          // time. Hook them into the global ctors list in that case:
+          [&](Function *Ctor, Function *) { appendToGlobalCtors(M, Ctor, 0); });
 }
 
 static bool isVtableAccess(Instruction *I) {
@@ -402,7 +432,8 @@ void ThreadSanitizer::InsertRuntimeIgnores(Function &F) {
   }
 }
 
-bool ThreadSanitizer::runOnFunction(Function &F) {
+bool ThreadSanitizer::sanitizeFunction(Function &F,
+                                       const TargetLibraryInfo &TLI) {
   // This is required to prevent instrumenting call to __tsan_init from within
   // the module constructor.
   if (&F == TsanCtorFunction)
@@ -416,8 +447,6 @@ bool ThreadSanitizer::runOnFunction(Function &F) {
   bool HasCalls = false;
   bool SanitizeFunction = F.hasFnAttribute(Attribute::SanitizeThread);
   const DataLayout &DL = F.getParent()->getDataLayout();
-  const TargetLibraryInfo *TLI =
-      &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
 
   // Traverse all instructions, collect loads/stores/returns, check for calls.
   for (auto &BB : F) {
@@ -428,7 +457,7 @@ bool ThreadSanitizer::runOnFunction(Function &F) {
         LocalLoadsAndStores.push_back(&Inst);
       else if (isa<CallInst>(Inst) || isa<InvokeInst>(Inst)) {
         if (CallInst *CI = dyn_cast<CallInst>(&Inst))
-          maybeMarkSanitizerLibraryCallNoBuiltin(CI, TLI);
+          maybeMarkSanitizerLibraryCallNoBuiltin(CI, &TLI);
         if (isa<MemIntrinsic>(Inst))
           MemIntrinCalls.push_back(&Inst);
         HasCalls = true;