src/llvm/include/llvm/MC/MCWin64EH.h

   1 //===- MCWin64EH.h - Machine Code Win64 EH support --------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file contains declarations to support the Win64 Exception Handling
  11 // scheme in MC.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef LLVM_MC_MCWIN64EH_H
  16 #define LLVM_MC_MCWIN64EH_H
  17
  18 #include "llvm/Support/Win64EH.h"
  19 #include <cassert>
  20 #include <vector>
  21
  22 namespace llvm {
  23   class StringRef;
  24   class MCStreamer;
  25   class MCSymbol;
  26
  27   class MCWin64EHInstruction {
  28   public:
  29     typedef Win64EH::UnwindOpcodes OpType;
  30   private:
  31     OpType Operation;
  32     MCSymbol *Label;
  33     unsigned Offset;
  34     unsigned Register;
  35   public:
  36     MCWin64EHInstruction(OpType Op, MCSymbol *L, unsigned Reg)
  37       : Operation(Op), Label(L), Offset(0), Register(Reg) {
  38      assert(Op == Win64EH::UOP_PushNonVol);
  39     }
  40     MCWin64EHInstruction(MCSymbol *L, unsigned Size)
  41       : Operation(Size>128 ? Win64EH::UOP_AllocLarge : Win64EH::UOP_AllocSmall),
  42         Label(L), Offset(Size) { }
  43     MCWin64EHInstruction(OpType Op, MCSymbol *L, unsigned Reg, unsigned Off)
  44       : Operation(Op), Label(L), Offset(Off), Register(Reg) {
  45       assert(Op == Win64EH::UOP_SetFPReg ||
  46              Op == Win64EH::UOP_SaveNonVol ||
  47              Op == Win64EH::UOP_SaveNonVolBig ||
  48              Op == Win64EH::UOP_SaveXMM128 ||
  49              Op == Win64EH::UOP_SaveXMM128Big);
  50     }
  51     MCWin64EHInstruction(OpType Op, MCSymbol *L, bool Code)
  52       : Operation(Op), Label(L), Offset(Code ? 1 : 0) {
  53       assert(Op == Win64EH::UOP_PushMachFrame);
  54     }
  55     OpType getOperation() const { return Operation; }
  56     MCSymbol *getLabel() const { return Label; }
  57     unsigned getOffset() const { return Offset; }
  58     unsigned getSize() const { return Offset; }
  59     unsigned getRegister() const { return Register; }
  60     bool isPushCodeFrame() const { return Offset == 1; }
  61   };
  62
  63   struct MCWin64EHUnwindInfo {
  64     MCWin64EHUnwindInfo() : Begin(0), End(0), ExceptionHandler(0),
  65                             Function(0), PrologEnd(0), Symbol(0),
  66                             HandlesUnwind(false), HandlesExceptions(false),
  67                             LastFrameInst(-1), ChainedParent(0),
  68                             Instructions() {}
  69     MCSymbol *Begin;
  70     MCSymbol *End;
  71     const MCSymbol *ExceptionHandler;
  72     const MCSymbol *Function;
  73     MCSymbol *PrologEnd;
  74     MCSymbol *Symbol;
  75     bool HandlesUnwind;
  76     bool HandlesExceptions;
  77     int LastFrameInst;
  78     MCWin64EHUnwindInfo *ChainedParent;
  79     std::vector<MCWin64EHInstruction> Instructions;
  80   };
  81
  82   class MCWin64EHUnwindEmitter {
  83   public:
  84     static StringRef GetSectionSuffix(const MCSymbol *func);
  85     //
  86     // This emits the unwind info sections (.pdata and .xdata in PE/COFF).
  87     //
  88     static void Emit(MCStreamer &streamer);
  89     static void EmitUnwindInfo(MCStreamer &streamer, MCWin64EHUnwindInfo *info);
  90   };
  91 } // end namespace llvm
  92
  93 #endif