1 files changed, 103 insertions, 0 deletions
diff --git a/clang/lib/CodeGen/SanitizerMetadata.cpp b/clang/lib/CodeGen/SanitizerMetadata.cpp
new file mode 100644
index 000000000000..ebc9cd5529bc
--- /dev/null
+++ b/clang/lib/CodeGen/SanitizerMetadata.cpp
@@ -0,0 +1,103 @@
+//===--- SanitizerMetadata.cpp - Blacklist for sanitizers -----------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Class which emits metadata consumed by sanitizer instrumentation passes.
+//
+//===----------------------------------------------------------------------===//
+#include "SanitizerMetadata.h"
+#include "CodeGenModule.h"
+#include "clang/AST/Type.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/IR/Constants.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+SanitizerMetadata::SanitizerMetadata(CodeGenModule &CGM) : CGM(CGM) {}
+
+static bool isAsanHwasanOrMemTag(const SanitizerSet& SS) {
+  return SS.hasOneOf(SanitizerKind::Address | SanitizerKind::KernelAddress |
+                     SanitizerKind::HWAddress | SanitizerKind::KernelHWAddress |
+                     SanitizerKind::MemTag);
+}
+
+void SanitizerMetadata::reportGlobalToASan(llvm::GlobalVariable *GV,
+                                           SourceLocation Loc, StringRef Name,
+                                           QualType Ty, bool IsDynInit,
+                                           bool IsBlacklisted) {
+  if (!isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+    return;
+  IsDynInit &= !CGM.isInSanitizerBlacklist(GV, Loc, Ty, "init");
+  IsBlacklisted |= CGM.isInSanitizerBlacklist(GV, Loc, Ty);
+
+  llvm::Metadata *LocDescr = nullptr;
+  llvm::Metadata *GlobalName = nullptr;
+  llvm::LLVMContext &VMContext = CGM.getLLVMContext();
+  if (!IsBlacklisted) {
+    // Don't generate source location and global name if it is blacklisted -
+    // it won't be instrumented anyway.
+    LocDescr = getLocationMetadata(Loc);
+    if (!Name.empty())
+      GlobalName = llvm::MDString::get(VMContext, Name);
+  }
+
+  llvm::Metadata *GlobalMetadata[] = {
+      llvm::ConstantAsMetadata::get(GV), LocDescr, GlobalName,
+      llvm::ConstantAsMetadata::get(
+          llvm::ConstantInt::get(llvm::Type::getInt1Ty(VMContext), IsDynInit)),
+      llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+          llvm::Type::getInt1Ty(VMContext), IsBlacklisted))};
+
+  llvm::MDNode *ThisGlobal = llvm::MDNode::get(VMContext, GlobalMetadata);
+  llvm::NamedMDNode *AsanGlobals =
+      CGM.getModule().getOrInsertNamedMetadata("llvm.asan.globals");
+  AsanGlobals->addOperand(ThisGlobal);
+}
+
+void SanitizerMetadata::reportGlobalToASan(llvm::GlobalVariable *GV,
+                                           const VarDecl &D, bool IsDynInit) {
+  if (!isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+    return;
+  std::string QualName;
+  llvm::raw_string_ostream OS(QualName);
+  D.printQualifiedName(OS);
+
+  bool IsBlacklisted = false;
+  for (auto Attr : D.specific_attrs<NoSanitizeAttr>())
+    if (Attr->getMask() & SanitizerKind::Address)
+      IsBlacklisted = true;
+  reportGlobalToASan(GV, D.getLocation(), OS.str(), D.getType(), IsDynInit,
+                     IsBlacklisted);
+}
+
+void SanitizerMetadata::disableSanitizerForGlobal(llvm::GlobalVariable *GV) {
+  // For now, just make sure the global is not modified by the ASan
+  // instrumentation.
+  if (isAsanHwasanOrMemTag(CGM.getLangOpts().Sanitize))
+    reportGlobalToASan(GV, SourceLocation(), "", QualType(), false, true);
+}
+
+void SanitizerMetadata::disableSanitizerForInstruction(llvm::Instruction *I) {
+  I->setMetadata(CGM.getModule().getMDKindID("nosanitize"),
+                 llvm::MDNode::get(CGM.getLLVMContext(), None));
+}
+
+llvm::MDNode *SanitizerMetadata::getLocationMetadata(SourceLocation Loc) {
+  PresumedLoc PLoc = CGM.getContext().getSourceManager().getPresumedLoc(Loc);
+  if (!PLoc.isValid())
+    return nullptr;
+  llvm::LLVMContext &VMContext = CGM.getLLVMContext();
+  llvm::Metadata *LocMetadata[] = {
+      llvm::MDString::get(VMContext, PLoc.getFilename()),
+      llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+          llvm::Type::getInt32Ty(VMContext), PLoc.getLine())),
+      llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+          llvm::Type::getInt32Ty(VMContext), PLoc.getColumn())),
+  };
+  return llvm::MDNode::get(VMContext, LocMetadata);
+}