1//===-- llvm/Support/Win64EH.h ---Win64 EH Constants-------------*- 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 constants and structures used for implementing 11// exception handling on Win64 platforms. For more information, see 12// http://msdn.microsoft.com/en-us/library/1eyas8tf.aspx 13// 14//===----------------------------------------------------------------------===// 15 16#ifndef LLVM_SUPPORT_WIN64EH_H 17#define LLVM_SUPPORT_WIN64EH_H 18 19#include "llvm/Support/DataTypes.h" 20#include "llvm/Support/Endian.h" 21 22namespace llvm { 23namespace Win64EH { 24 25/// UnwindOpcodes - Enumeration whose values specify a single operation in 26/// the prolog of a function. 27enum UnwindOpcodes { 28 UOP_PushNonVol = 0, 29 UOP_AllocLarge, 30 UOP_AllocSmall, 31 UOP_SetFPReg, 32 UOP_SaveNonVol, 33 UOP_SaveNonVolBig, 34 UOP_SaveXMM128 = 8, 35 UOP_SaveXMM128Big, 36 UOP_PushMachFrame 37}; 38 39/// UnwindCode - This union describes a single operation in a function prolog, 40/// or part thereof. 41union UnwindCode { 42 struct { 43 support::ulittle8_t CodeOffset; 44 support::ulittle8_t UnwindOpAndOpInfo; 45 } u; 46 support::ulittle16_t FrameOffset; 47 48 uint8_t getUnwindOp() const { 49 return u.UnwindOpAndOpInfo & 0x0F; 50 } 51 uint8_t getOpInfo() const { 52 return (u.UnwindOpAndOpInfo >> 4) & 0x0F; 53 } 54}; 55 56enum { 57 /// UNW_ExceptionHandler - Specifies that this function has an exception 58 /// handler. 59 UNW_ExceptionHandler = 0x01, 60 /// UNW_TerminateHandler - Specifies that this function has a termination 61 /// handler. 62 UNW_TerminateHandler = 0x02, 63 /// UNW_ChainInfo - Specifies that this UnwindInfo structure is chained to 64 /// another one. 65 UNW_ChainInfo = 0x04 66}; 67 68/// RuntimeFunction - An entry in the table of functions with unwind info. 69struct RuntimeFunction { 70 support::ulittle32_t StartAddress; 71 support::ulittle32_t EndAddress; 72 support::ulittle32_t UnwindInfoOffset; 73}; 74 75/// UnwindInfo - An entry in the exception table. 76struct UnwindInfo { 77 support::ulittle8_t VersionAndFlags; 78 support::ulittle8_t PrologSize; 79 support::ulittle8_t NumCodes; 80 support::ulittle8_t FrameRegisterAndOffset; 81 UnwindCode UnwindCodes[1]; 82 83 uint8_t getVersion() const { 84 return VersionAndFlags & 0x07; 85 } 86 uint8_t getFlags() const { 87 return (VersionAndFlags >> 3) & 0x1f; 88 } 89 uint8_t getFrameRegister() const { 90 return FrameRegisterAndOffset & 0x0f; 91 } 92 uint8_t getFrameOffset() const { 93 return (FrameRegisterAndOffset >> 4) & 0x0f; 94 } 95 96 // The data after unwindCodes depends on flags. 97 // If UNW_ExceptionHandler or UNW_TerminateHandler is set then follows 98 // the address of the language-specific exception handler. 99 // If UNW_ChainInfo is set then follows a RuntimeFunction which defines 100 // the chained unwind info. 101 // For more information please see MSDN at: 102 // http://msdn.microsoft.com/en-us/library/ddssxxy8.aspx 103 104 /// \brief Return pointer to language specific data part of UnwindInfo. 105 void *getLanguageSpecificData() { 106 return reinterpret_cast<void *>(&UnwindCodes[(NumCodes+1) & ~1]); 107 } 108 109 /// \brief Return pointer to language specific data part of UnwindInfo. 110 const void *getLanguageSpecificData() const { 111 return reinterpret_cast<const void *>(&UnwindCodes[(NumCodes+1) & ~1]); 112 } 113 114 /// \brief Return image-relative offset of language-specific exception handler. 115 uint32_t getLanguageSpecificHandlerOffset() const { 116 return *reinterpret_cast<const uint32_t *>(getLanguageSpecificData()); 117 } 118 119 /// \brief Set image-relative offset of language-specific exception handler. 120 void setLanguageSpecificHandlerOffset(uint32_t offset) { 121 *reinterpret_cast<uint32_t *>(getLanguageSpecificData()) = offset; 122 } 123 124 /// \brief Return pointer to exception-specific data. 125 void *getExceptionData() { 126 return reinterpret_cast<void *>(reinterpret_cast<uint32_t *>( 127 getLanguageSpecificData())+1); 128 } 129 130 /// \brief Return pointer to chained unwind info. 131 RuntimeFunction *getChainedFunctionEntry() { 132 return reinterpret_cast<RuntimeFunction *>(getLanguageSpecificData()); 133 } 134 135 /// \brief Return pointer to chained unwind info. 136 const RuntimeFunction *getChainedFunctionEntry() const { 137 return reinterpret_cast<const RuntimeFunction *>(getLanguageSpecificData()); 138 } 139}; 140 141 142} // End of namespace Win64EH 143} // End of namespace llvm 144 145#endif 146