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 } 45