20 files changed, 351 insertions, 2 deletions
diff --git a/clang/include/clang/Driver/CLCompatOptions.td b/clang/include/clang/Driver/CLCompatOptions.td
index c1f0a89b5dc..c1bc7eea3c3 100644
--- a/clang/include/clang/Driver/CLCompatOptions.td
+++ b/clang/include/clang/Driver/CLCompatOptions.td
@@ -235,6 +235,8 @@ def _SLASH_Fi : CLCompileJoined<"Fi">,
 def _SLASH_Fo : CLCompileJoined<"Fo">,
   HelpText<"Set output object file, or directory (ends in / or \\) (with /c)">,
   MetaVarName<"<file or directory>">;
+def _SLASH_Guard : CLJoined<"guard:">,
+  HelpText<"Enable Control Flow Guard with /guard:cf">;
 def _SLASH_GX : CLFlag<"GX">,
   HelpText<"Enable exception handling">;
 def _SLASH_GX_ : CLFlag<"GX-">,
@@ -364,7 +366,6 @@ def _SLASH_GL_ : CLFlag<"GL-">;
 def _SLASH_Gm : CLFlag<"Gm">;
 def _SLASH_Gm_ : CLFlag<"Gm-">;
 def _SLASH_GT : CLFlag<"GT">;
-def _SLASH_Guard : CLJoined<"guard:">;
 def _SLASH_GZ : CLFlag<"GZ">;
 def _SLASH_H : CLFlag<"H">;
 def _SLASH_homeparams : CLFlag<"homeparams">;
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index d84613c0591..822fccc26d5 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -492,6 +492,8 @@ def bind__at__load : Flag<["-"], "bind_at_load">;
 def bundle__loader : Separate<["-"], "bundle_loader">;
 def bundle : Flag<["-"], "bundle">;
 def b : JoinedOrSeparate<["-"], "b">, Flags<[Unsupported]>;
+def cfguard : Flag<["-"], "cfguard">, Flags<[CC1Option]>,
+  HelpText<"Emit tables required for Windows Control Flow Guard.">;
 def cl_opt_disable : Flag<["-"], "cl-opt-disable">, Group<opencl_Group>, Flags<[CC1Option]>,
   HelpText<"OpenCL only. This option disables all optimizations. By default optimizations are enabled.">;
 def cl_strict_aliasing : Flag<["-"], "cl-strict-aliasing">, Group<opencl_Group>, Flags<[CC1Option]>,
diff --git a/clang/include/clang/Frontend/CodeGenOptions.def b/clang/include/clang/Frontend/CodeGenOptions.def
index 0ee3bb11976..69ba39f971a 100644
--- a/clang/include/clang/Frontend/CodeGenOptions.def
+++ b/clang/include/clang/Frontend/CodeGenOptions.def
@@ -38,6 +38,7 @@ CODEGENOPT(AssumeSaneOperatorNew , 1, 1) ///< implicit __attribute__((malloc)) o
 CODEGENOPT(Autolink          , 1, 1) ///< -fno-autolink
 CODEGENOPT(ObjCAutoRefCountExceptions , 1, 0) ///< Whether ARC should be EH-safe.
 CODEGENOPT(Backchain         , 1, 0) ///< -mbackchain
+CODEGENOPT(ControlFlowGuard  , 1, 0) ///< -cfguard
 CODEGENOPT(CoverageExtraChecksum, 1, 0) ///< Whether we need a second checksum for functions in GCNO files.
 CODEGENOPT(CoverageNoFunctionNamesInData, 1, 0) ///< Do not include function names in GCDA files.
 CODEGENOPT(CoverageExitBlockBeforeBody, 1, 0) ///< Whether to emit the exit block before the body blocks in GCNO files.
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index df33fc3e820..0a417548d4d 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -456,6 +456,10 @@ void CodeGenModule::Release() {
     // Indicate that we want CodeView in the metadata.
     getModule().addModuleFlag(llvm::Module::Warning, "CodeView", 1);
   }
+  if (CodeGenOpts.ControlFlowGuard) {
+    // We want function ID tables for Control Flow Guard.
+    getModule().addModuleFlag(llvm::Module::Warning, "cfguard", 1);
+  }
   if (CodeGenOpts.OptimizationLevel > 0 && CodeGenOpts.StrictVTablePointers) {
     // We don't support LTO with 2 with different StrictVTablePointers
     // FIXME: we could support it by stripping all the information introduced
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index b7241d2f6be..e302c44c9dc 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -5074,6 +5074,10 @@ void Clang::AddClangCLArgs(const ArgList &Args, types::ID InputType,
     else
       CmdArgs.push_back("msvc");
   }
+
+  if (Args.hasArg(options::OPT__SLASH_Guard) &&
+      Args.getLastArgValue(options::OPT__SLASH_Guard).equals_lower("cf"))
+    CmdArgs.push_back("-cfguard");
 }
 
 visualstudio::Compiler *Clang::getCLFallback() const {
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 22528004688..236ee627969 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -721,6 +721,8 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   Opts.MainFileName = Args.getLastArgValue(OPT_main_file_name);
   Opts.VerifyModule = !Args.hasArg(OPT_disable_llvm_verifier);
 
+  Opts.ControlFlowGuard = Args.hasArg(OPT_cfguard);
+
   Opts.DisableGCov = Args.hasArg(OPT_test_coverage);
   Opts.EmitGcovArcs = Args.hasArg(OPT_femit_coverage_data);
   Opts.EmitGcovNotes = Args.hasArg(OPT_femit_coverage_notes);
diff --git a/llvm/include/llvm/MC/MCObjectFileInfo.h b/llvm/include/llvm/MC/MCObjectFileInfo.h
index 79bf2b97015..8f5ca4dee65 100644
--- a/llvm/include/llvm/MC/MCObjectFileInfo.h
+++ b/llvm/include/llvm/MC/MCObjectFileInfo.h
@@ -196,6 +196,7 @@ protected:
   MCSection *PDataSection;
   MCSection *XDataSection;
   MCSection *SXDataSection;
+  MCSection *GFIDsSection;
 
 public:
   void InitMCObjectFileInfo(const Triple &TT, bool PIC, MCContext &ctx,
@@ -349,6 +350,7 @@ public:
   MCSection *getPDataSection() const { return PDataSection; }
   MCSection *getXDataSection() const { return XDataSection; }
   MCSection *getSXDataSection() const { return SXDataSection; }
+  MCSection *getGFIDsSection() const { return GFIDsSection; }
 
   MCSection *getEHFrameSection() {
     return EHFrameSection;
diff --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index a8205170070..62d8e337b6a 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -499,6 +499,9 @@ public:
 
   virtual void EmitCOFFSafeSEH(MCSymbol const *Symbol);
 
+  /// \brief Emits the symbol table index of a Symbol into the current section.
+  virtual void EmitCOFFSymbolIndex(MCSymbol const *Symbol);
+
   /// \brief Emits a COFF section index.
   ///
   /// \param Symbol - Symbol the section number relocation should point to.
diff --git a/llvm/include/llvm/MC/MCWinCOFFStreamer.h b/llvm/include/llvm/MC/MCWinCOFFStreamer.h
index a2500c06efa..60c17cac9f2 100644
--- a/llvm/include/llvm/MC/MCWinCOFFStreamer.h
+++ b/llvm/include/llvm/MC/MCWinCOFFStreamer.h
@@ -50,6 +50,7 @@ public:
   void EmitCOFFSymbolType(int Type) override;
   void EndCOFFSymbolDef() override;
   void EmitCOFFSafeSEH(MCSymbol const *Symbol) override;
+  void EmitCOFFSymbolIndex(MCSymbol const *Symbol) override;
   void EmitCOFFSectionIndex(MCSymbol const *Symbol) override;
   void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset) override;
   void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index d7995447592..7ffb5ddc2d6 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -16,6 +16,7 @@
 #include "CodeViewDebug.h"
 #include "DwarfDebug.h"
 #include "DwarfException.h"
+#include "WinCFGuard.h"
 #include "WinException.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/ADT/APInt.h"
@@ -130,6 +131,8 @@ static const char *const DbgTimerName = "emit";
 static const char *const DbgTimerDescription = "Debug Info Emission";
 static const char *const EHTimerName = "write_exception";
 static const char *const EHTimerDescription = "DWARF Exception Writer";
+static const char *const CFGuardName = "Control Flow Guard";
+static const char *const CFGuardDescription = "Control Flow Guard Tables";
 static const char *const CodeViewLineTablesGroupName = "linetables";
 static const char *const CodeViewLineTablesGroupDescription =
   "CodeView Line Tables";
@@ -354,6 +357,13 @@ bool AsmPrinter::doInitialization(Module &M) {
   if (ES)
     Handlers.push_back(HandlerInfo(ES, EHTimerName, EHTimerDescription,
                                    DWARFGroupName, DWARFGroupDescription));
+
+  if (mdconst::extract_or_null<ConstantInt>(
+          MMI->getModule()->getModuleFlag("cfguard")))
+    Handlers.push_back(HandlerInfo(new WinCFGuard(this), CFGuardName,
+                                   CFGuardDescription, DWARFGroupName,
+                                   DWARFGroupDescription));
+
   return false;
 }
 
diff --git a/llvm/lib/CodeGen/AsmPrinter/CMakeLists.txt b/llvm/lib/CodeGen/AsmPrinter/CMakeLists.txt
index 05c6a28bbca..f21810f0b05 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CMakeLists.txt
+++ b/llvm/lib/CodeGen/AsmPrinter/CMakeLists.txt
@@ -20,6 +20,7 @@ add_llvm_library(LLVMAsmPrinter
   EHStreamer.cpp
   ErlangGCPrinter.cpp
   OcamlGCPrinter.cpp
+  WinCFGuard.cpp
   WinException.cpp
   CodeViewDebug.cpp
 
diff --git a/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.cpp b/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.cpp
new file mode 100644
index 00000000000..18d37caf57e
--- /dev/null
+++ b/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.cpp
@@ -0,0 +1,45 @@
+//===-- CodeGen/AsmPrinter/WinCFGuard.cpp - Control Flow Guard Impl ------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing Win64 exception info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "WinCFGuard.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineOperand.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Metadata.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCStreamer.h"
+
+#include <vector>
+
+using namespace llvm;
+
+WinCFGuard::WinCFGuard(AsmPrinter *A) : AsmPrinterHandler(), Asm(A) {}
+
+WinCFGuard::~WinCFGuard() {}
+
+void WinCFGuard::endModule() {
+  const Module *M = Asm->MMI->getModule();
+  std::vector<const Function *> Functions;
+  for (const Function &F : *M)
+    if (F.hasAddressTaken())
+      Functions.push_back(&F);
+  if (Functions.empty())
+    return;
+  auto &OS = *Asm->OutStreamer;
+  OS.SwitchSection(Asm->OutContext.getObjectFileInfo()->getGFIDsSection());
+  for (const Function *F : Functions)
+    OS.EmitCOFFSymbolIndex(Asm->getSymbol(F));
+}
diff --git a/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.h b/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.h
new file mode 100644
index 00000000000..553b4ae261c
--- /dev/null
+++ b/llvm/lib/CodeGen/AsmPrinter/WinCFGuard.h
@@ -0,0 +1,54 @@
+//===-- WinCFGuard.h - Windows Control Flow Guard Handling ----*- C++ -*--===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains support for writing windows exception info into asm files.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_WINCFGUARD_H
+#define LLVM_LIB_CODEGEN_ASMPRINTER_WINCFGUARD_H
+
+#include "AsmPrinterHandler.h"
+#include "llvm/Support/Compiler.h"
+
+namespace llvm {
+
+class LLVM_LIBRARY_VISIBILITY WinCFGuard : public AsmPrinterHandler {
+  /// Target of directive emission.
+  AsmPrinter *Asm;
+
+public:
+  WinCFGuard(AsmPrinter *A);
+  ~WinCFGuard() override;
+
+  void setSymbolSize(const MCSymbol *Sym, uint64_t Size) override {}
+
+  /// \brief Emit the Control Flow Guard function ID table
+  void endModule() override;
+
+  /// \brief Gather pre-function debug information.
+  /// Every beginFunction(MF) call should be followed by an endFunction(MF)
+  /// call.
+  void beginFunction(const MachineFunction *MF) override {}
+
+  /// \brief Gather post-function debug information.
+  /// Please note that some AsmPrinter implementations may not call
+  /// beginFunction at all.
+  void endFunction(const MachineFunction *MF) override {}
+
+  /// \brief Process beginning of an instruction.
+  void beginInstruction(const MachineInstr *MI) override {}
+
+  /// \brief Process end of an instruction.
+  void endInstruction() override {}
+};
+
+} // namespace llvm
+
+#endif
diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index e521b6e7c70..cd8c1d317b0 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -151,6 +151,7 @@ public:
   void EmitCOFFSymbolType(int Type) override;
   void EndCOFFSymbolDef() override;
   void EmitCOFFSafeSEH(MCSymbol const *Symbol) override;
+  void EmitCOFFSymbolIndex(MCSymbol const *Symbol) override;
   void EmitCOFFSectionIndex(MCSymbol const *Symbol) override;
   void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset) override;
   void emitELFSize(MCSymbol *Symbol, const MCExpr *Value) override;
@@ -653,6 +654,12 @@ void MCAsmStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitCOFFSymbolIndex(MCSymbol const *Symbol) {
+  OS << "\t.symidx\t";
+  Symbol->print(OS, MAI);
+  EmitEOL();
+}
+
 void MCAsmStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
   OS << "\t.secidx\t";
   Symbol->print(OS, MAI);
diff --git a/llvm/lib/MC/MCObjectFileInfo.cpp b/llvm/lib/MC/MCObjectFileInfo.cpp
index a6b5c43f1d2..f0f4dee8fc1 100644
--- a/llvm/lib/MC/MCObjectFileInfo.cpp
+++ b/llvm/lib/MC/MCObjectFileInfo.cpp
@@ -819,6 +819,11 @@ void MCObjectFileInfo::initCOFFMCObjectFileInfo(const Triple &T) {
   SXDataSection = Ctx->getCOFFSection(".sxdata", COFF::IMAGE_SCN_LNK_INFO,
                                       SectionKind::getMetadata());
 
+  GFIDsSection = Ctx->getCOFFSection(".gfids$y",
+                                     COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+                                         COFF::IMAGE_SCN_MEM_READ,
+                                     SectionKind::getMetadata());
+
   TLSDataSection = Ctx->getCOFFSection(
       ".tls$", COFF::IMAGE_SCN_CNT_INITIALIZED_DATA | COFF::IMAGE_SCN_MEM_READ |
                    COFF::IMAGE_SCN_MEM_WRITE,
diff --git a/llvm/lib/MC/MCParser/COFFAsmParser.cpp b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
index 687e0cc1faa..2a754eab05b 100644
--- a/llvm/lib/MC/MCParser/COFFAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/COFFAsmParser.cpp
@@ -65,8 +65,9 @@ class COFFAsmParser : public MCAsmParserExtension {
     addDirectiveHandler<&COFFAsmParser::ParseDirectiveType>(".type");
     addDirectiveHandler<&COFFAsmParser::ParseDirectiveEndef>(".endef");
     addDirectiveHandler<&COFFAsmParser::ParseDirectiveSecRel32>(".secrel32");
-    addDirectiveHandler<&COFFAsmParser::ParseDirectiveSecIdx>(".secidx");
+    addDirectiveHandler<&COFFAsmParser::ParseDirectiveSymIdx>(".symidx");
     addDirectiveHandler<&COFFAsmParser::ParseDirectiveSafeSEH>(".safeseh");
+    addDirectiveHandler<&COFFAsmParser::ParseDirectiveSecIdx>(".secidx");
     addDirectiveHandler<&COFFAsmParser::ParseDirectiveLinkOnce>(".linkonce");
 
     // Win64 EH directives.
@@ -130,6 +131,7 @@ class COFFAsmParser : public MCAsmParserExtension {
   bool ParseDirectiveSecRel32(StringRef, SMLoc);
   bool ParseDirectiveSecIdx(StringRef, SMLoc);
   bool ParseDirectiveSafeSEH(StringRef, SMLoc);
+  bool ParseDirectiveSymIdx(StringRef, SMLoc);
   bool parseCOMDATType(COFF::COMDATType &Type);
   bool ParseDirectiveLinkOnce(StringRef, SMLoc);
 
@@ -520,6 +522,21 @@ bool COFFAsmParser::ParseDirectiveSecIdx(StringRef, SMLoc) {
   return false;
 }
 
+bool COFFAsmParser::ParseDirectiveSymIdx(StringRef, SMLoc) {
+  StringRef SymbolID;
+  if (getParser().parseIdentifier(SymbolID))
+    return TokError("expected identifier in directive");
+
+  if (getLexer().isNot(AsmToken::EndOfStatement))
+    return TokError("unexpected token in directive");
+
+  MCSymbol *Symbol = getContext().getOrCreateSymbol(SymbolID);
+
+  Lex();
+  getStreamer().EmitCOFFSymbolIndex(Symbol);
+  return false;
+}
+
 /// ::= [ identifier ]
 bool COFFAsmParser::parseCOMDATType(COFF::COMDATType &Type) {
   StringRef TypeId = getTok().getIdentifier();
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index 6e801ed8777..78469c3f9a3 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -804,6 +804,8 @@ void MCStreamer::EmitWinCFIEndProlog(SMLoc Loc) {
 void MCStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
 }
 
+void MCStreamer::EmitCOFFSymbolIndex(MCSymbol const *Symbol) {}
+
 void MCStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
 }
 
diff --git a/llvm/lib/MC/MCWinCOFFStreamer.cpp b/llvm/lib/MC/MCWinCOFFStreamer.cpp
index c2583d95c5e..1f0b64dae73 100644
--- a/llvm/lib/MC/MCWinCOFFStreamer.cpp
+++ b/llvm/lib/MC/MCWinCOFFStreamer.cpp
@@ -193,6 +193,17 @@ void MCWinCOFFStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
                    << COFF::SCT_COMPLEX_TYPE_SHIFT);
 }
 
+void MCWinCOFFStreamer::EmitCOFFSymbolIndex(MCSymbol const *Symbol) {
+  MCSection *Sec = getCurrentSectionOnly();
+  getAssembler().registerSection(*Sec);
+  if (Sec->getAlignment() < 4)
+    Sec->setAlignment(4);
+
+  new MCSymbolIdFragment(Symbol, getCurrentSectionOnly());
+
+  getAssembler().registerSymbol(*Symbol);
+}
+
 void MCWinCOFFStreamer::EmitCOFFSectionIndex(const MCSymbol *Symbol) {
   visitUsedSymbol(*Symbol);
   MCDataFragment *DF = getOrCreateDataFragment();
diff --git a/llvm/test/CodeGen/WinCFGuard/cfguard.ll b/llvm/test/CodeGen/WinCFGuard/cfguard.ll
new file mode 100644
index 00000000000..128bab15b51
--- /dev/null
+++ b/llvm/test/CodeGen/WinCFGuard/cfguard.ll
@@ -0,0 +1,162 @@
+; RUN: llc < %s | FileCheck %s
+
+; CHECK: .section .gfids$y
+; CHECK: .symidx "?address_taken@@YAXXZ"
+; CHECK: .symidx "?virt_method@Derived@@UEBAHXZ"
+
+; ModuleID = 'cfguard.cpp'
+source_filename = "cfguard.cpp"
+target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-pc-windows-msvc"
+
+%struct.Derived = type { %struct.Base }
+%struct.Base = type { i32 (...)** }
+%rtti.CompleteObjectLocator = type { i32, i32, i32, i32, i32, i32 }
+%rtti.TypeDescriptor13 = type { i8**, i8*, [14 x i8] }
+%rtti.ClassHierarchyDescriptor = type { i32, i32, i32, i32 }
+%rtti.BaseClassDescriptor = type { i32, i32, i32, i32, i32, i32, i32 }
+%rtti.TypeDescriptor10 = type { i8**, i8*, [11 x i8] }
+
+$"\01??0Derived@@QEAA@XZ" = comdat any
+
+$"\01??0Base@@QEAA@XZ" = comdat any
+
+$"\01?virt_method@Derived@@UEBAHXZ" = comdat any
+
+$"\01??_7Derived@@6B@" = comdat largest
+
+$"\01??_R4Derived@@6B@" = comdat any
+
+$"\01??_R0?AUDerived@@@8" = comdat any
+
+$"\01??_R3Derived@@8" = comdat any
+
+$"\01??_R2Derived@@8" = comdat any
+
+$"\01??_R1A@?0A@EA@Derived@@8" = comdat any
+
+$"\01??_R1A@?0A@EA@Base@@8" = comdat any
+
+$"\01??_R0?AUBase@@@8" = comdat any
+
+$"\01??_R3Base@@8" = comdat any
+
+$"\01??_R2Base@@8" = comdat any
+
+$"\01??_7Base@@6B@" = comdat largest
+
+$"\01??_R4Base@@6B@" = comdat any
+
+@"\01?D@@3UDerived@@A" = global %struct.Derived zeroinitializer, align 8
+@0 = private unnamed_addr constant { [2 x i8*] } { [2 x i8*] [i8* bitcast (%rtti.CompleteObjectLocator* @"\01??_R4Derived@@6B@" to i8*), i8* bitcast (i32 (%struct.Derived*)* @"\01?virt_method@Derived@@UEBAHXZ" to i8*)] }, comdat($"\01??_7Derived@@6B@")
+@"\01??_R4Derived@@6B@" = linkonce_odr constant %rtti.CompleteObjectLocator { i32 1, i32 0, i32 0, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.TypeDescriptor13* @"\01??_R0?AUDerived@@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.ClassHierarchyDescriptor* @"\01??_R3Derived@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.CompleteObjectLocator* @"\01??_R4Derived@@6B@" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@"\01??_7type_info@@6B@" = external constant i8*
+@"\01??_R0?AUDerived@@@8" = linkonce_odr global %rtti.TypeDescriptor13 { i8** @"\01??_7type_info@@6B@", i8* null, [14 x i8] c".?AUDerived@@\00" }, comdat
+@__ImageBase = external constant i8
+@"\01??_R3Derived@@8" = linkonce_odr constant %rtti.ClassHierarchyDescriptor { i32 0, i32 0, i32 2, i32 trunc (i64 sub nuw nsw (i64 ptrtoint ([3 x i32]* @"\01??_R2Derived@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@"\01??_R2Derived@@8" = linkonce_odr constant [3 x i32] [i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.BaseClassDescriptor* @"\01??_R1A@?0A@EA@Derived@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.BaseClassDescriptor* @"\01??_R1A@?0A@EA@Base@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 0], comdat
+@"\01??_R1A@?0A@EA@Derived@@8" = linkonce_odr constant %rtti.BaseClassDescriptor { i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.TypeDescriptor13* @"\01??_R0?AUDerived@@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 1, i32 0, i32 -1, i32 0, i32 64, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.ClassHierarchyDescriptor* @"\01??_R3Derived@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@"\01??_R1A@?0A@EA@Base@@8" = linkonce_odr constant %rtti.BaseClassDescriptor { i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.TypeDescriptor10* @"\01??_R0?AUBase@@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 0, i32 0, i32 -1, i32 0, i32 64, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.ClassHierarchyDescriptor* @"\01??_R3Base@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@"\01??_R0?AUBase@@@8" = linkonce_odr global %rtti.TypeDescriptor10 { i8** @"\01??_7type_info@@6B@", i8* null, [11 x i8] c".?AUBase@@\00" }, comdat
+@"\01??_R3Base@@8" = linkonce_odr constant %rtti.ClassHierarchyDescriptor { i32 0, i32 0, i32 1, i32 trunc (i64 sub nuw nsw (i64 ptrtoint ([2 x i32]* @"\01??_R2Base@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@"\01??_R2Base@@8" = linkonce_odr constant [2 x i32] [i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.BaseClassDescriptor* @"\01??_R1A@?0A@EA@Base@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 0], comdat
+@1 = private unnamed_addr constant { [2 x i8*] } { [2 x i8*] [i8* bitcast (%rtti.CompleteObjectLocator* @"\01??_R4Base@@6B@" to i8*), i8* bitcast (void ()* @_purecall to i8*)] }, comdat($"\01??_7Base@@6B@")
+@"\01??_R4Base@@6B@" = linkonce_odr constant %rtti.CompleteObjectLocator { i32 1, i32 0, i32 0, i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.TypeDescriptor10* @"\01??_R0?AUBase@@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.ClassHierarchyDescriptor* @"\01??_R3Base@@8" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32), i32 trunc (i64 sub nuw nsw (i64 ptrtoint (%rtti.CompleteObjectLocator* @"\01??_R4Base@@6B@" to i64), i64 ptrtoint (i8* @__ImageBase to i64)) to i32) }, comdat
+@llvm.global_ctors = appending global [1 x { i32, void ()*, i8* }] [{ i32, void ()*, i8* } { i32 65535, void ()* @_GLOBAL__sub_I_cfguard.cpp, i8* null }]
+
+@"\01??_7Derived@@6B@" = unnamed_addr alias i8*, getelementptr inbounds ({ [2 x i8*] }, { [2 x i8*] }* @0, i32 0, i32 0, i32 1)
+@"\01??_7Base@@6B@" = unnamed_addr alias i8*, getelementptr inbounds ({ [2 x i8*] }, { [2 x i8*] }* @1, i32 0, i32 0, i32 1)
+
+; Function Attrs: noinline nounwind
+define internal void @"\01??__ED@@YAXXZ"() #0 {
+entry:
+  %call = call %struct.Derived* @"\01??0Derived@@QEAA@XZ"(%struct.Derived* @"\01?D@@3UDerived@@A") #2
+  ret void
+}
+
+; Function Attrs: noinline nounwind optnone
+define linkonce_odr %struct.Derived* @"\01??0Derived@@QEAA@XZ"(%struct.Derived* returned %this) unnamed_addr #1 comdat align 2 {
+entry:
+  %this.addr = alloca %struct.Derived*, align 8
+  store %struct.Derived* %this, %struct.Derived** %this.addr, align 8
+  %this1 = load %struct.Derived*, %struct.Derived** %this.addr, align 8
+  %0 = bitcast %struct.Derived* %this1 to %struct.Base*
+  %call = call %struct.Base* @"\01??0Base@@QEAA@XZ"(%struct.Base* %0) #2
+  %1 = bitcast %struct.Derived* %this1 to i32 (...)***
+  store i32 (...)** bitcast (i8** @"\01??_7Derived@@6B@" to i32 (...)**), i32 (...)*** %1, align 8
+  ret %struct.Derived* %this1
+}
+
+; Function Attrs: noinline nounwind optnone
+define void @"\01?address_taken@@YAXXZ"() #1 {
+entry:
+  ret void
+}
+
+; Function Attrs: noinline nounwind optnone
+define void ()* @"\01?foo@@YAP6AXXZPEAUBase@@@Z"(%struct.Base* %B) #1 {
+entry:
+  %retval = alloca void ()*, align 8
+  %B.addr = alloca %struct.Base*, align 8
+  store %struct.Base* %B, %struct.Base** %B.addr, align 8
+  %0 = load %struct.Base*, %struct.Base** %B.addr, align 8
+  %1 = bitcast %struct.Base* %0 to i32 (%struct.Base*)***
+  %vtable = load i32 (%struct.Base*)**, i32 (%struct.Base*)*** %1, align 8
+  %vfn = getelementptr inbounds i32 (%struct.Base*)*, i32 (%struct.Base*)** %vtable, i64 0
+  %2 = load i32 (%struct.Base*)*, i32 (%struct.Base*)** %vfn, align 8
+  %call = call i32 %2(%struct.Base* %0)
+  %tobool = icmp ne i32 %call, 0
+  br i1 %tobool, label %if.then, label %if.end
+
+if.then:                                          ; preds = %entry
+  store void ()* @"\01?address_taken@@YAXXZ", void ()** %retval, align 8
+  br label %return
+
+if.end:                                           ; preds = %entry
+  store void ()* null, void ()** %retval, align 8
+  br label %return
+
+return:                                           ; preds = %if.end, %if.then
+  %3 = load void ()*, void ()** %retval, align 8
+  ret void ()* %3
+}
+
+; Function Attrs: noinline nounwind optnone
+define linkonce_odr %struct.Base* @"\01??0Base@@QEAA@XZ"(%struct.Base* returned %this) unnamed_addr #1 comdat align 2 {
+entry:
+  %this.addr = alloca %struct.Base*, align 8
+  store %struct.Base* %this, %struct.Base** %this.addr, align 8
+  %this1 = load %struct.Base*, %struct.Base** %this.addr, align 8
+  %0 = bitcast %struct.Base* %this1 to i32 (...)***
+  store i32 (...)** bitcast (i8** @"\01??_7Base@@6B@" to i32 (...)**), i32 (...)*** %0, align 8
+  ret %struct.Base* %this1
+}
+
+; Function Attrs: noinline nounwind optnone
+define linkonce_odr i32 @"\01?virt_method@Derived@@UEBAHXZ"(%struct.Derived* %this) unnamed_addr #1 comdat align 2 {
+entry:
+  %this.addr = alloca %struct.Derived*, align 8
+  store %struct.Derived* %this, %struct.Derived** %this.addr, align 8
+  %this1 = load %struct.Derived*, %struct.Derived** %this.addr, align 8
+  ret i32 42
+}
+
+declare dllimport void @_purecall() unnamed_addr
+
+; Function Attrs: noinline nounwind
+define internal void @_GLOBAL__sub_I_cfguard.cpp() #0 {
+entry:
+  call void @"\01??__ED@@YAXXZ"()
+  ret void
+}
+
+attributes #0 = { noinline nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-features"="+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { noinline nounwind optnone "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-features"="+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind }
+
+!llvm.module.flags = !{!0, !1}
+!llvm.ident = !{!2}
+
+!0 = !{i32 2, !"cfguard", i32 1}
+!1 = !{i32 1, !"wchar_size", i32 2}
+!2 = !{!"clang version 6.0.0 "}
diff --git a/llvm/test/MC/COFF/symidx.s b/llvm/test/MC/COFF/symidx.s
new file mode 100644
index 00000000000..46c00334764
--- /dev/null
+++ b/llvm/test/MC/COFF/symidx.s
@@ -0,0 +1,15 @@
+// RUN: llvm-mc -triple x86_64-pc-win32 -filetype=obj %s | llvm-objdump -s -t - | FileCheck %s
+.text
+foo:
+  ret
+bar:
+  ret
+.data
+.symidx	bar
+.symidx	foo
+
+// CHECK:      Contents of section .data:
+// CHECK-NEXT:  0000 0[[BAR:[1-9]]]000000 0[[FOO:[1-9]]]000000
+// CHECK:      SYMBOL TABLE:
+// CHECK:      [ [[FOO]]](sec  1)(fl 0x00)(ty   0)(scl   3) (nx 0) 0x00000000 foo
+// CHECK-NEXT: [ [[BAR]]](sec  1)(fl 0x00)(ty   0)(scl   3) (nx 0) 0x00000001 bar