[ASan] Completely remove sanitizer blacklist file from instrumentatio…

…n pass.

All blacklisting logic is now moved to the frontend (Clang).
If a function (or source file it is in) is blacklisted, it doesn't
get sanitize_address attribute and is therefore not instrumented.
If a global variable (or source file it is in) is blacklisted, it is
reported to be blacklisted by the entry in llvm.asan.globals metadata,
and is not modified by the instrumentation.

The latter may lead to certain false positives - not all the globals
created by Clang are described in llvm.asan.globals metadata (e.g,
RTTI descriptors are not), so we may start reporting errors on them
even if "module" they appear in is blacklisted. We assume it's fine
to take such risk:
  1) errors on these globals are rare and usually indicate wild memory access
  2) we can lazily add descriptors for these globals into llvm.asan.globals
     lazily.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212505 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/Instrumentation.h

@@ -65,8 +65,7 @@ ModulePass *createGCOVProfilerPass(const GCOVOptions &Options =
 
 // Insert AddressSanitizer (address sanity checking) instrumentation
 FunctionPass *createAddressSanitizerFunctionPass();
-ModulePass *
-createAddressSanitizerModulePass(StringRef BlacklistFile = StringRef());
+ModulePass *createAddressSanitizerModulePass();
 
 // Insert MemorySanitizer instrumentation (detection of uninitialized reads)
 FunctionPass *createMemorySanitizerPass(int TrackOrigins = 0);

lib/Transforms/Instrumentation/AddressSanitizer.cpp

@@ -45,7 +45,6 @@
 #include "llvm/Transforms/Utils/Cloning.h"
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Transforms/Utils/ModuleUtils.h"
-#include "llvm/Transforms/Utils/SpecialCaseList.h"
 #include <algorithm>
 #include <string>
 #include <system_error>
@@ -149,9 +148,6 @@ static cl::opt<bool> ClInvalidPointerPairs("asan-detect-invalid-pointer-pair",
 static cl::opt<unsigned> ClRealignStack("asan-realign-stack",
        cl::desc("Realign stack to the value of this flag (power of two)"),
        cl::Hidden, cl::init(32));
-static cl::opt<std::string> ClBlacklistFile("asan-blacklist",
-       cl::desc("File containing the list of objects to ignore "
-                "during instrumentation"), cl::Hidden);
 static cl::opt<int> ClInstrumentationWithCallsThreshold(
     "asan-instrumentation-with-call-threshold",
        cl::desc("If the function being instrumented contains more than "
@@ -418,9 +414,7 @@ struct AddressSanitizer : public FunctionPass {
 
 class AddressSanitizerModule : public ModulePass {
  public:
-  AddressSanitizerModule(StringRef BlacklistFile = StringRef())
-      : ModulePass(ID), BlacklistFile(BlacklistFile.empty() ? ClBlacklistFile
-                                                            : BlacklistFile) {}
+  AddressSanitizerModule() : ModulePass(ID) {}
   bool runOnModule(Module &M) override;
   static char ID;  // Pass identification, replacement for typeid
   const char *getPassName() const override {
@@ -438,9 +432,6 @@ class AddressSanitizerModule : public ModulePass {
     return RedzoneSizeForScale(Mapping.Scale);
   }
 
-  SmallString<64> BlacklistFile;
-
-  std::unique_ptr<SpecialCaseList> BL;
   GlobalsMetadata GlobalsMD;
   Type *IntptrTy;
   LLVMContext *C;
@@ -601,8 +592,8 @@ char AddressSanitizerModule::ID = 0;
 INITIALIZE_PASS(AddressSanitizerModule, "asan-module",
     "AddressSanitizer: detects use-after-free and out-of-bounds bugs."
     "ModulePass", false, false)
-ModulePass *llvm::createAddressSanitizerModulePass(StringRef BlacklistFile) {
-  return new AddressSanitizerModule(BlacklistFile);
+ModulePass *llvm::createAddressSanitizerModulePass() {
+  return new AddressSanitizerModule();
 }
 
 static size_t TypeSizeToSizeIndex(uint32_t TypeSize) {
@@ -926,9 +917,6 @@ bool AddressSanitizerModule::ShouldInstrumentGlobal(GlobalVariable *G) {
   Type *Ty = cast<PointerType>(G->getType())->getElementType();
   DEBUG(dbgs() << "GLOBAL: " << *G << "\n");
 
-  // FIXME: Don't use the blacklist here, all the data should be collected
-  // by the frontend and passed in globals metadata.
-  if (BL->isIn(*G)) return false;
   if (GlobalsMD.isBlacklisted(G)) return false;
   if (GlobalsMD.isSourceLocationGlobal(G)) return false;
   if (!Ty->isSized()) return false;
@@ -1163,7 +1151,6 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
   if (!DLP)
     return false;
   DL = &DLP->getDataLayout();
-  BL.reset(SpecialCaseList::createOrDie(BlacklistFile));
   C = &(M.getContext());
   int LongSize = DL->getPointerSizeInBits();
   IntptrTy = Type::getIntNTy(*C, LongSize);
@@ -1183,7 +1170,8 @@ bool AddressSanitizerModule::runOnModule(Module &M) {
     Changed = true;
   }
 
-  if (ClGlobals && !BL->isIn(M)) Changed |= InstrumentGlobals(IRB, M);
+  if (ClGlobals)
+    Changed |= InstrumentGlobals(IRB, M);
 
   return Changed;
 }