[ASan] Minor fixes to dynamic allocas handling:

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

diff --git a/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index ce29ff9ecfbaaa93c2d609b321ed07b184bdaf51..876701367a1823b0d84fa530802a17a516c5672b 100644 (file)
--- a/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -338,7 +338,7 @@ struct ShadowMapping {
 
 static ShadowMapping getShadowMapping(Triple &TargetTriple, int LongSize,
                                       bool IsKasan) {
-  bool IsAndroid = TargetTriple.getEnvironment() == llvm::Triple::Android;
+  bool IsAndroid = TargetTriple.isAndroid();
   bool IsIOS = TargetTriple.isiOS();
   bool IsFreeBSD = TargetTriple.isOSFreeBSD();
   bool IsLinux = TargetTriple.isOSLinux();
@@ -729,7 +729,7 @@ struct FunctionStackPoisoner : public InstVisitor<FunctionStackPoisoner> {
                      Instruction *ThenTerm, Value *ValueIfFalse);
 };
 
-}  // namespace
+} // anonymous namespace
 
 char AddressSanitizer::ID = 0;
 INITIALIZE_PASS_BEGIN(
@@ -737,6 +737,7 @@ INITIALIZE_PASS_BEGIN(
     "AddressSanitizer: detects use-after-free and out-of-bounds bugs.", false,
     false)
 INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
+INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
 INITIALIZE_PASS_END(
     AddressSanitizer, "asan",
     "AddressSanitizer: detects use-after-free and out-of-bounds bugs.", false,
@@ -839,8 +840,7 @@ bool AddressSanitizer::isInterestingAlloca(AllocaInst &AI) {
        getAllocaSizeInBytes(&AI) > 0 &&
        // We are only interested in allocas not promotable to registers.
        // Promotable allocas are common under -O0.
-       (!ClSkipPromotableAllocas || !isAllocaPromotable(&AI) ||
-        isDynamicAlloca(AI)));
+       (!ClSkipPromotableAllocas || !isAllocaPromotable(&AI)));
 
   ProcessedAllocas[&AI] = IsInteresting;
   return IsInteresting;
@@ -959,7 +959,7 @@ void AddressSanitizer::instrumentMop(ObjectSizeOffsetVisitor &ObjSizeVis,
     // If initialization order checking is disabled, a simple access to a
     // dynamically initialized global is always valid.
     GlobalVariable *G = dyn_cast<GlobalVariable>(GetUnderlyingObject(Addr, DL));
-    if (G != NULL && (!ClInitializers || GlobalIsLinkerInitialized(G)) &&
+    if (G && (!ClInitializers || GlobalIsLinkerInitialized(G)) &&
         isSafeAccess(ObjSizeVis, Addr, TypeSize)) {
       NumOptimizedAccessesToGlobalVar++;
       return;
@@ -1124,7 +1124,8 @@ void AddressSanitizer::instrumentUnusualSizeOrAlignment(
 void AddressSanitizerModule::poisonOneInitializer(Function &GlobalInit,
                                                   GlobalValue *ModuleName) {
   // Set up the arguments to our poison/unpoison functions.
-  IRBuilder<> IRB(GlobalInit.begin()->getFirstInsertionPt());
+  IRBuilder<> IRB(&GlobalInit.front(),
+                  GlobalInit.front().getFirstInsertionPt());
 
   // Add a call to poison all external globals before the given function starts.
   Value *ModuleNameAddr = ConstantExpr::getPointerCast(ModuleName, IntptrTy);
@@ -1187,6 +1188,14 @@ bool AddressSanitizerModule::ShouldInstrumentGlobal(GlobalVariable *G) {
     // Do not instrument globals from special LLVM sections.
     if (Section.find("__llvm") != StringRef::npos) return false;
 
+    // Do not instrument function pointers to initialization and termination
+    // routines: dynamic linker will not properly handle redzones.
+    if (Section.startswith(".preinit_array") ||
+        Section.startswith(".init_array") ||
+        Section.startswith(".fini_array")) {
+      return false;
+    }
+
     // Callbacks put into the CRT initializer/terminator sections
     // should not be instrumented.
     // See https://code.google.com/p/address-sanitizer/issues/detail?id=305
@@ -1506,7 +1515,7 @@ bool AddressSanitizer::maybeInsertAsanInitAtFunctionEntry(Function &F) {
   // We cannot just ignore these methods, because they may call other
   // instrumented functions.
   if (F.getName().find(" load]") != std::string::npos) {
-    IRBuilder<> IRB(F.begin()->begin());
+    IRBuilder<> IRB(&F.front(), F.front().begin());
     IRB.CreateCall(AsanInitFunction, {});
     return true;
   }
@@ -1789,6 +1798,16 @@ void FunctionStackPoisoner::createDynamicAllocasInitStorage() {
 void FunctionStackPoisoner::poisonStack() {
   assert(AllocaVec.size() > 0 || DynamicAllocaVec.size() > 0);
 
+  // Insert poison calls for lifetime intrinsics for alloca.
+  bool HavePoisonedAllocas = false;
+  for (const auto &APC : AllocaPoisonCallVec) {
+    assert(APC.InsBefore);
+    assert(APC.AI);
+    IRBuilder<> IRB(APC.InsBefore);
+    poisonAlloca(APC.AI, APC.Size, IRB, APC.DoPoison);
+    HavePoisonedAllocas |= APC.DoPoison;
+  }
+
   if (ClInstrumentAllocas && DynamicAllocaVec.size() > 0) {
     // Handle dynamic allocas.
     createDynamicAllocasInitStorage();
@@ -1797,7 +1816,7 @@ void FunctionStackPoisoner::poisonStack() {
     unpoisonDynamicAllocas();
   }
 
-  if (AllocaVec.size() == 0) return;
+  if (AllocaVec.empty()) return;
 
   int StackMallocIdx = -1;
   DebugLoc EntryDebugLocation;
@@ -1813,8 +1832,8 @@ void FunctionStackPoisoner::poisonStack() {
   // regular stack slots.
   auto InsBeforeB = InsBefore->getParent();
   assert(InsBeforeB == &F.getEntryBlock());
-  for (BasicBlock::iterator I = InsBefore; I != InsBeforeB->end(); ++I)
-    if (auto *AI = dyn_cast_or_null<AllocaInst>(I))
+  for (BasicBlock::iterator I(InsBefore); I != InsBeforeB->end(); ++I)
+    if (auto *AI = dyn_cast<AllocaInst>(I))
       if (NonInstrumentedStaticAllocaVec.count(AI) > 0)
         AI->moveBefore(InsBefore);
 
@@ -1896,16 +1915,6 @@ void FunctionStackPoisoner::poisonStack() {
         DoDynamicAlloca ? createAllocaForLayout(IRB, L, true) : StaticAlloca;
   }
 
-  // Insert poison calls for lifetime intrinsics for alloca.
-  bool HavePoisonedAllocas = false;
-  for (const auto &APC : AllocaPoisonCallVec) {
-    assert(APC.InsBefore);
-    assert(APC.AI);
-    IRBuilder<> IRB(APC.InsBefore);
-    poisonAlloca(APC.AI, APC.Size, IRB, APC.DoPoison);
-    HavePoisonedAllocas |= APC.DoPoison;
-  }
-
   // Replace Alloca instructions with base+offset.
   for (const auto &Desc : SVD) {
     AllocaInst *AI = Desc.AI;