aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/llvm12/include/llvm/Support/Win64EH.h
blob: 78057486b4a85976ebd2d01195fc7503e13c4919 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
#pragma once

#ifdef __GNUC__
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif

//===-- llvm/Support/Win64EH.h ---Win64 EH Constants-------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains constants and structures used for implementing
// exception handling on Win64 platforms. For more information, see
// http://msdn.microsoft.com/en-us/library/1eyas8tf.aspx
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_WIN64EH_H
#define LLVM_SUPPORT_WIN64EH_H

#include "llvm/Support/DataTypes.h"
#include "llvm/Support/Endian.h"

namespace llvm {
namespace Win64EH {

/// UnwindOpcodes - Enumeration whose values specify a single operation in
/// the prolog of a function.
enum UnwindOpcodes {
  UOP_PushNonVol = 0,
  UOP_AllocLarge,
  UOP_AllocSmall,
  UOP_SetFPReg,
  UOP_SaveNonVol,
  UOP_SaveNonVolBig,
  UOP_Epilog,
  UOP_SpareCode,
  UOP_SaveXMM128,
  UOP_SaveXMM128Big,
  UOP_PushMachFrame,
  // The following set of unwind opcodes is for ARM64.  They are documented at
  // https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling
  UOP_AllocMedium,
  UOP_SaveR19R20X, 
  UOP_SaveFPLRX,
  UOP_SaveFPLR,
  UOP_SaveReg,
  UOP_SaveRegX,
  UOP_SaveRegP,
  UOP_SaveRegPX,
  UOP_SaveLRPair, 
  UOP_SaveFReg,
  UOP_SaveFRegX,
  UOP_SaveFRegP,
  UOP_SaveFRegPX,
  UOP_SetFP,
  UOP_AddFP,
  UOP_Nop,
  UOP_End, 
  UOP_SaveNext, 
  UOP_TrapFrame, 
  UOP_Context, 
  UOP_ClearUnwoundToCall 
};

/// UnwindCode - This union describes a single operation in a function prolog,
/// or part thereof.
union UnwindCode {
  struct {
    uint8_t CodeOffset;
    uint8_t UnwindOpAndOpInfo;
  } u;
  support::ulittle16_t FrameOffset;

  uint8_t getUnwindOp() const {
    return u.UnwindOpAndOpInfo & 0x0F;
  }
  uint8_t getOpInfo() const {
    return (u.UnwindOpAndOpInfo >> 4) & 0x0F;
  }
};

enum {
  /// UNW_ExceptionHandler - Specifies that this function has an exception
  /// handler.
  UNW_ExceptionHandler = 0x01,
  /// UNW_TerminateHandler - Specifies that this function has a termination
  /// handler.
  UNW_TerminateHandler = 0x02,
  /// UNW_ChainInfo - Specifies that this UnwindInfo structure is chained to
  /// another one.
  UNW_ChainInfo = 0x04
};

/// RuntimeFunction - An entry in the table of functions with unwind info.
struct RuntimeFunction {
  support::ulittle32_t StartAddress;
  support::ulittle32_t EndAddress;
  support::ulittle32_t UnwindInfoOffset;
};

/// UnwindInfo - An entry in the exception table.
struct UnwindInfo {
  uint8_t VersionAndFlags;
  uint8_t PrologSize;
  uint8_t NumCodes;
  uint8_t FrameRegisterAndOffset;
  UnwindCode UnwindCodes[1];

  uint8_t getVersion() const {
    return VersionAndFlags & 0x07;
  }
  uint8_t getFlags() const {
    return (VersionAndFlags >> 3) & 0x1f;
  }
  uint8_t getFrameRegister() const {
    return FrameRegisterAndOffset & 0x0f;
  }
  uint8_t getFrameOffset() const {
    return (FrameRegisterAndOffset >> 4) & 0x0f;
  }

  // The data after unwindCodes depends on flags.
  // If UNW_ExceptionHandler or UNW_TerminateHandler is set then follows
  // the address of the language-specific exception handler.
  // If UNW_ChainInfo is set then follows a RuntimeFunction which defines
  // the chained unwind info.
  // For more information please see MSDN at:
  // http://msdn.microsoft.com/en-us/library/ddssxxy8.aspx

  /// Return pointer to language specific data part of UnwindInfo.
  void *getLanguageSpecificData() {
    return reinterpret_cast<void *>(&UnwindCodes[(NumCodes+1) & ~1]);
  }

  /// Return pointer to language specific data part of UnwindInfo.
  const void *getLanguageSpecificData() const {
    return reinterpret_cast<const void *>(&UnwindCodes[(NumCodes + 1) & ~1]);
  }

  /// Return image-relative offset of language-specific exception handler.
  uint32_t getLanguageSpecificHandlerOffset() const {
    return *reinterpret_cast<const support::ulittle32_t *>(
               getLanguageSpecificData());
  }

  /// Set image-relative offset of language-specific exception handler.
  void setLanguageSpecificHandlerOffset(uint32_t offset) {
    *reinterpret_cast<support::ulittle32_t *>(getLanguageSpecificData()) =
        offset;
  }

  /// Return pointer to exception-specific data.
  void *getExceptionData() {
    return reinterpret_cast<void *>(reinterpret_cast<uint32_t *>(
                                                  getLanguageSpecificData())+1);
  }

  /// Return pointer to chained unwind info.
  RuntimeFunction *getChainedFunctionEntry() {
    return reinterpret_cast<RuntimeFunction *>(getLanguageSpecificData());
  }

  /// Return pointer to chained unwind info.
  const RuntimeFunction *getChainedFunctionEntry() const {
    return reinterpret_cast<const RuntimeFunction *>(getLanguageSpecificData());
  }
};


} // End of namespace Win64EH
} // End of namespace llvm

#endif

#ifdef __GNUC__
#pragma GCC diagnostic pop
#endif