1 //===-- WinCFGuard.h - Windows Control Flow Guard Handling ----*- C++ -*--===// 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 the metadata for Windows Control Flow 10 // Guard, including address-taken functions, and valid longjmp targets. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_WINCFGUARD_H 15 #define LLVM_LIB_CODEGEN_ASMPRINTER_WINCFGUARD_H 16 17 #include "llvm/CodeGen/AsmPrinterHandler.h" 18 #include "llvm/Support/Compiler.h" 19 #include <vector> 20 21 namespace llvm { 22 23 class LLVM_LIBRARY_VISIBILITY WinCFGuard : public AsmPrinterHandler { 24 /// Target of directive emission. 25 AsmPrinter *Asm; 26 std::vector<const MCSymbol *> LongjmpTargets; 27 MCSymbol *lookupImpSymbol(const MCSymbol *Sym); 28 29 public: 30 WinCFGuard(AsmPrinter *A); 31 ~WinCFGuard() override; 32 33 void setSymbolSize(const MCSymbol *Sym, uint64_t Size) override {} 34 35 /// Emit the Control Flow Guard function ID table. 36 void endModule() override; 37 38 /// Gather pre-function debug information. 39 /// Every beginFunction(MF) call should be followed by an endFunction(MF) 40 /// call. 41 void beginFunction(const MachineFunction *MF) override {} 42 43 /// Gather post-function debug information. 44 /// Please note that some AsmPrinter implementations may not call 45 /// beginFunction at all. 46 void endFunction(const MachineFunction *MF) override; 47 48 /// Process beginning of an instruction. 49 void beginInstruction(const MachineInstr *MI) override {} 50 51 /// Process end of an instruction. 52 void endInstruction() override {} 53 }; 54 55 } // namespace llvm 56 57 #endif 58