//===--- SanitizerMetadata.cpp - Ignored entities 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/Attr.h"

#include "clang/AST/Type.h"

#include "clang/Basic/SourceManager.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::MemTag);

}

SanitizerMask expandKernelSanitizerMasks(SanitizerMask Mask) {

  if (Mask & (SanitizerKind::Address | SanitizerKind::KernelAddress))

    Mask |= SanitizerKind::Address | SanitizerKind::KernelAddress;

  // Note: KHWASan doesn't support globals.

  return Mask;

}

void SanitizerMetadata::reportGlobal(llvm::GlobalVariable *GV,

                                     SourceLocation Loc, StringRef Name,

                                     QualType Ty,

                                     SanitizerMask NoSanitizeAttrMask,

                                     bool IsDynInit) {

  SanitizerSet FsanitizeArgument = CGM.getLangOpts().Sanitize;

  if (!isAsanHwasanOrMemTag(FsanitizeArgument))

    return;

  FsanitizeArgument.Mask = expandKernelSanitizerMasks(FsanitizeArgument.Mask);

  NoSanitizeAttrMask = expandKernelSanitizerMasks(NoSanitizeAttrMask);

  SanitizerSet NoSanitizeAttrSet = {NoSanitizeAttrMask &

                                    FsanitizeArgument.Mask};

  llvm::GlobalVariable::SanitizerMetadata Meta;

  if (GV->hasSanitizerMetadata())

    Meta = GV->getSanitizerMetadata();

  Meta.NoAddress |= NoSanitizeAttrSet.hasOneOf(SanitizerKind::Address);

  Meta.NoAddress |= CGM.isInNoSanitizeList(

      FsanitizeArgument.Mask & SanitizerKind::Address, GV, Loc, Ty);

  Meta.NoHWAddress |= NoSanitizeAttrSet.hasOneOf(SanitizerKind::HWAddress);

  Meta.NoHWAddress |= CGM.isInNoSanitizeList(

      FsanitizeArgument.Mask & SanitizerKind::HWAddress, GV, Loc, Ty);

  Meta.Memtag |=

      static_cast<bool>(FsanitizeArgument.Mask & SanitizerKind::MemtagGlobals);

  Meta.Memtag &= !NoSanitizeAttrSet.hasOneOf(SanitizerKind::MemTag);

  Meta.Memtag &= !CGM.isInNoSanitizeList(

      FsanitizeArgument.Mask & SanitizerKind::MemTag, GV, Loc, Ty);

  Meta.IsDynInit = IsDynInit && 
!Meta.NoAddress75
 &&

                   
FsanitizeArgument.has(SanitizerKind::Address)71
 &&

                   !CGM.isInNoSanitizeList(SanitizerKind::Address |

                                               SanitizerKind::KernelAddress,

                                           GV, Loc, Ty, "init");

  GV->setSanitizerMetadata(Meta);

}

void SanitizerMetadata::reportGlobal(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);

  auto getNoSanitizeMask = [](const VarDecl &D) {

    if (D.hasAttr<DisableSanitizerInstrumentationAttr>())

      return SanitizerKind::All;

    SanitizerMask NoSanitizeMask;

    for (auto *Attr : D.specific_attrs<NoSanitizeAttr>())

      NoSanitizeMask |= Attr->getMask();

    return NoSanitizeMask;

  };

  reportGlobal(GV, D.getLocation(), OS.str(), D.getType(), getNoSanitizeMask(D),

               IsDynInit);

}

void SanitizerMetadata::disableSanitizerForGlobal(llvm::GlobalVariable *GV) {

  reportGlobal(GV, SourceLocation(), "", QualType(), SanitizerKind::All);

}

void SanitizerMetadata::disableSanitizerForInstruction(llvm::Instruction *I) {

  I->setMetadata(llvm::LLVMContext::MD_nosanitize,

                 llvm::MDNode::get(CGM.getLLVMContext(), None));

}