lib/CodeGen/AsmPrinter/WinCFGuard.cpp

   1 //===-- CodeGen/AsmPrinter/WinCFGuard.cpp - Control Flow Guard Impl ------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file contains support for writing Win64 exception info into asm files.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "WinCFGuard.h"
  14 #include "llvm/CodeGen/AsmPrinter.h"
  15 #include "llvm/CodeGen/MachineFunction.h"
  16 #include "llvm/CodeGen/MachineModuleInfo.h"
  17 #include "llvm/CodeGen/MachineOperand.h"
  18 #include "llvm/IR/Constants.h"
  19 #include "llvm/IR/Metadata.h"
  20 #include "llvm/MC/MCAsmInfo.h"
  21 #include "llvm/MC/MCObjectFileInfo.h"
  22 #include "llvm/MC/MCStreamer.h"
  23
  24 #include <vector>
  25
  26 using namespace llvm;
  27
  28 WinCFGuard::WinCFGuard(AsmPrinter *A) : AsmPrinterHandler(), Asm(A) {}
  29
  30 WinCFGuard::~WinCFGuard() {}
  31
  32 void WinCFGuard::endModule() {
  33   const Module *M = Asm->MMI->getModule();
  34   std::vector<const Function *> Functions;
  35   for (const Function &F : *M)
  36     if (F.hasAddressTaken())
  37       Functions.push_back(&F);
  38   if (Functions.empty())
  39     return;
  40   auto &OS = *Asm->OutStreamer;
  41   OS.SwitchSection(Asm->OutContext.getObjectFileInfo()->getGFIDsSection());
  42   for (const Function *F : Functions)
  43     OS.EmitCOFFSymbolIndex(Asm->getSymbol(F));
  44 }