1 | //===-- llvm/Support/Win64EH.h ---Win64 EH Constants-------------*- 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 constants and structures used for implementing |
10 | // exception handling on Win64 platforms. For more information, see |
11 | // http://msdn.microsoft.com/en-us/library/1eyas8tf.aspx |
12 | // |
13 | //===----------------------------------------------------------------------===// |
14 | |
15 | #ifndef LLVM_SUPPORT_WIN64EH_H |
16 | #define LLVM_SUPPORT_WIN64EH_H |
17 | |
18 | #include "llvm/Support/DataTypes.h" |
19 | #include "llvm/Support/Endian.h" |
20 | |
21 | namespace llvm { |
22 | namespace Win64EH { |
23 | |
24 | /// UnwindOpcodes - Enumeration whose values specify a single operation in |
25 | /// the prolog of a function. |
26 | enum UnwindOpcodes { |
27 | // The following set of unwind opcodes is for x86_64. They are documented at |
28 | // https://docs.microsoft.com/en-us/cpp/build/exception-handling-x64. |
29 | // Some generic values from this set are used for other architectures too. |
30 | UOP_PushNonVol = 0, |
31 | UOP_AllocLarge, |
32 | UOP_AllocSmall, |
33 | UOP_SetFPReg, |
34 | UOP_SaveNonVol, |
35 | UOP_SaveNonVolBig, |
36 | UOP_Epilog, |
37 | UOP_SpareCode, |
38 | UOP_SaveXMM128, |
39 | UOP_SaveXMM128Big, |
40 | UOP_PushMachFrame, |
41 | // The following set of unwind opcodes is for ARM64. They are documented at |
42 | // https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling |
43 | UOP_AllocMedium, |
44 | UOP_SaveR19R20X, |
45 | UOP_SaveFPLRX, |
46 | UOP_SaveFPLR, |
47 | UOP_SaveReg, |
48 | UOP_SaveRegX, |
49 | UOP_SaveRegP, |
50 | UOP_SaveRegPX, |
51 | UOP_SaveLRPair, |
52 | UOP_SaveFReg, |
53 | UOP_SaveFRegX, |
54 | UOP_SaveFRegP, |
55 | UOP_SaveFRegPX, |
56 | UOP_SetFP, |
57 | UOP_AddFP, |
58 | UOP_Nop, |
59 | UOP_End, |
60 | UOP_SaveNext, |
61 | UOP_TrapFrame, |
62 | UOP_Context, |
63 | UOP_ECContext, |
64 | UOP_ClearUnwoundToCall, |
65 | UOP_PACSignLR, |
66 | UOP_SaveAnyRegI, |
67 | UOP_SaveAnyRegIP, |
68 | UOP_SaveAnyRegD, |
69 | UOP_SaveAnyRegDP, |
70 | UOP_SaveAnyRegQ, |
71 | UOP_SaveAnyRegQP, |
72 | UOP_SaveAnyRegIX, |
73 | UOP_SaveAnyRegIPX, |
74 | UOP_SaveAnyRegDX, |
75 | UOP_SaveAnyRegDPX, |
76 | UOP_SaveAnyRegQX, |
77 | UOP_SaveAnyRegQPX, |
78 | |
79 | // The following set of unwind opcodes is for ARM. They are documented at |
80 | // https://docs.microsoft.com/en-us/cpp/build/arm-exception-handling |
81 | |
82 | // Stack allocations use UOP_AllocSmall, UOP_AllocLarge from above, plus |
83 | // the following. AllocSmall, AllocLarge and AllocHuge represent a 16 bit |
84 | // instruction, while the WideAlloc* opcodes represent a 32 bit instruction. |
85 | // Small can represent a stack offset of 0x7f*4 (252) bytes, Medium can |
86 | // represent up to 0x3ff*4 (4092) bytes, Large up to 0xffff*4 (262140) bytes, |
87 | // and Huge up to 0xffffff*4 (67108860) bytes. |
88 | UOP_AllocHuge, |
89 | UOP_WideAllocMedium, |
90 | UOP_WideAllocLarge, |
91 | UOP_WideAllocHuge, |
92 | |
93 | UOP_WideSaveRegMask, |
94 | UOP_SaveSP, |
95 | UOP_SaveRegsR4R7LR, |
96 | UOP_WideSaveRegsR4R11LR, |
97 | UOP_SaveFRegD8D15, |
98 | UOP_SaveRegMask, |
99 | UOP_SaveLR, |
100 | UOP_SaveFRegD0D15, |
101 | UOP_SaveFRegD16D31, |
102 | // Using UOP_Nop from above |
103 | UOP_WideNop, |
104 | // Using UOP_End from above |
105 | UOP_EndNop, |
106 | UOP_WideEndNop, |
107 | // A custom unspecified opcode, consisting of one or more bytes. This |
108 | // allows producing opcodes in the implementation defined/reserved range. |
109 | UOP_Custom, |
110 | }; |
111 | |
112 | /// UnwindCode - This union describes a single operation in a function prolog, |
113 | /// or part thereof. |
114 | union UnwindCode { |
115 | struct { |
116 | uint8_t CodeOffset; |
117 | uint8_t UnwindOpAndOpInfo; |
118 | } u; |
119 | support::ulittle16_t FrameOffset; |
120 | |
121 | uint8_t getUnwindOp() const { |
122 | return u.UnwindOpAndOpInfo & 0x0F; |
123 | } |
124 | uint8_t getOpInfo() const { |
125 | return (u.UnwindOpAndOpInfo >> 4) & 0x0F; |
126 | } |
127 | }; |
128 | |
129 | enum { |
130 | /// UNW_ExceptionHandler - Specifies that this function has an exception |
131 | /// handler. |
132 | UNW_ExceptionHandler = 0x01, |
133 | /// UNW_TerminateHandler - Specifies that this function has a termination |
134 | /// handler. |
135 | UNW_TerminateHandler = 0x02, |
136 | /// UNW_ChainInfo - Specifies that this UnwindInfo structure is chained to |
137 | /// another one. |
138 | UNW_ChainInfo = 0x04 |
139 | }; |
140 | |
141 | /// RuntimeFunction - An entry in the table of functions with unwind info. |
142 | struct RuntimeFunction { |
143 | support::ulittle32_t StartAddress; |
144 | support::ulittle32_t EndAddress; |
145 | support::ulittle32_t UnwindInfoOffset; |
146 | }; |
147 | |
148 | /// UnwindInfo - An entry in the exception table. |
149 | struct UnwindInfo { |
150 | uint8_t VersionAndFlags; |
151 | uint8_t PrologSize; |
152 | uint8_t NumCodes; |
153 | uint8_t FrameRegisterAndOffset; |
154 | UnwindCode UnwindCodes[1]; |
155 | |
156 | uint8_t getVersion() const { |
157 | return VersionAndFlags & 0x07; |
158 | } |
159 | uint8_t getFlags() const { |
160 | return (VersionAndFlags >> 3) & 0x1f; |
161 | } |
162 | uint8_t getFrameRegister() const { |
163 | return FrameRegisterAndOffset & 0x0f; |
164 | } |
165 | uint8_t getFrameOffset() const { |
166 | return (FrameRegisterAndOffset >> 4) & 0x0f; |
167 | } |
168 | |
169 | // The data after unwindCodes depends on flags. |
170 | // If UNW_ExceptionHandler or UNW_TerminateHandler is set then follows |
171 | // the address of the language-specific exception handler. |
172 | // If UNW_ChainInfo is set then follows a RuntimeFunction which defines |
173 | // the chained unwind info. |
174 | // For more information please see MSDN at: |
175 | // http://msdn.microsoft.com/en-us/library/ddssxxy8.aspx |
176 | |
177 | /// Return pointer to language specific data part of UnwindInfo. |
178 | void *getLanguageSpecificData() { |
179 | return reinterpret_cast<void *>(&UnwindCodes[(NumCodes+1) & ~1]); |
180 | } |
181 | |
182 | /// Return pointer to language specific data part of UnwindInfo. |
183 | const void *getLanguageSpecificData() const { |
184 | return reinterpret_cast<const void *>(&UnwindCodes[(NumCodes + 1) & ~1]); |
185 | } |
186 | |
187 | /// Return image-relative offset of language-specific exception handler. |
188 | uint32_t getLanguageSpecificHandlerOffset() const { |
189 | return *reinterpret_cast<const support::ulittle32_t *>( |
190 | getLanguageSpecificData()); |
191 | } |
192 | |
193 | /// Set image-relative offset of language-specific exception handler. |
194 | void setLanguageSpecificHandlerOffset(uint32_t offset) { |
195 | *reinterpret_cast<support::ulittle32_t *>(getLanguageSpecificData()) = |
196 | offset; |
197 | } |
198 | |
199 | /// Return pointer to exception-specific data. |
200 | void *getExceptionData() { |
201 | return reinterpret_cast<void *>(reinterpret_cast<uint32_t *>( |
202 | getLanguageSpecificData())+1); |
203 | } |
204 | |
205 | /// Return pointer to chained unwind info. |
206 | RuntimeFunction *getChainedFunctionEntry() { |
207 | return reinterpret_cast<RuntimeFunction *>(getLanguageSpecificData()); |
208 | } |
209 | |
210 | /// Return pointer to chained unwind info. |
211 | const RuntimeFunction *getChainedFunctionEntry() const { |
212 | return reinterpret_cast<const RuntimeFunction *>(getLanguageSpecificData()); |
213 | } |
214 | }; |
215 | |
216 | |
217 | } // End of namespace Win64EH |
218 | } // End of namespace llvm |
219 | |
220 | #endif |
221 | |