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 
28 public:
29   WinCFGuard(AsmPrinter *A);
30   ~WinCFGuard() override;
31 
32   void setSymbolSize(const MCSymbol *Sym, uint64_t Size) override {}
33 
34   /// Emit the Control Flow Guard function ID table.
35   void endModule() override;
36 
37   /// Gather pre-function debug information.
38   /// Every beginFunction(MF) call should be followed by an endFunction(MF)
39   /// call.
40   void beginFunction(const MachineFunction *MF) override {}
41 
42   /// Gather post-function debug information.
43   /// Please note that some AsmPrinter implementations may not call
44   /// beginFunction at all.
45   void endFunction(const MachineFunction *MF) override;
46 
47   /// Process beginning of an instruction.
48   void beginInstruction(const MachineInstr *MI) override {}
49 
50   /// Process end of an instruction.
51   void endInstruction() override {}
52 };
53 
54 } // namespace llvm
55 
56 #endif
57