diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp index db9dd1f8c61..42d3cb68446 100644 --- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp +++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp @@ -1561,6 +1561,7 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M) { size_t n = GlobalsToChange.size(); if (n == 0) return false; + auto &DL = M.getDataLayout(); bool UseComdatMetadata = TargetTriple.isOSBinFormatCOFF(); bool UseMachOGlobalsSection = ShouldUseMachOGlobalsSection(); bool UseMetadataArray = !(UseComdatMetadata || UseMachOGlobalsSection); @@ -1578,6 +1579,10 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M) { StructType *GlobalStructTy = StructType::get(IntptrTy, IntptrTy, IntptrTy, IntptrTy, IntptrTy, IntptrTy, IntptrTy, IntptrTy, nullptr); + unsigned SizeOfGlobalStruct = DL.getTypeAllocSize(GlobalStructTy); + assert((isPowerOf2_32(SizeOfGlobalStruct) || + !TargetTriple.isOSBinFormatCOFF()) && + "global metadata will not be padded appropriately"); SmallVector<Constant *, 16> Initializers(UseMetadataArray ? n : 0); // On recent Mach-O platforms, use a structure which binds the liveness of @@ -1596,7 +1601,6 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M) { GlobalVariable *ModuleName = createPrivateGlobalForString( M, M.getModuleIdentifier(), /*AllowMerging*/ false); - auto &DL = M.getDataLayout(); for (size_t i = 0; i < n; i++) { static const uint64_t kMaxGlobalRedzone = 1 << 18; GlobalVariable *G = GlobalsToChange[i]; @@ -1743,7 +1747,14 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M) { Initializer, Twine("__asan_global_") + GlobalValue::getRealLinkageName(G->getName())); Metadata->setSection(getGlobalMetadataSection()); - Metadata->setAlignment(1); // Don't leave padding in between. + + // The MSVC linker always inserts padding when linking incrementally. We + // cope with that by aligning each struct to its size, which must be a power + // of two. + if (TargetTriple.isOSBinFormatCOFF()) + Metadata->setAlignment(SizeOfGlobalStruct); + else + Metadata->setAlignment(1); // Don't leave padding in between. // On platforms that support comdats, put the metadata and the // instrumented global in the same group. This ensures that the metadata |
