1 //===- Win64EHDumper.cpp - Win64 EH Printer ---------------------*- 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 #include "Win64EHDumper.h"
11 #include "llvm-readobj.h"
12 #include "llvm/Object/COFF.h"
13 #include "llvm/Support/ErrorHandling.h"
14 #include "llvm/Support/Format.h"
15
16 using namespace llvm;
17 using namespace llvm::object;
18 using namespace llvm::Win64EH;
19
20 static const EnumEntry<unsigned> UnwindFlags[] = {
21 { "ExceptionHandler", UNW_ExceptionHandler },
22 { "TerminateHandler", UNW_TerminateHandler },
23 { "ChainInfo" , UNW_ChainInfo }
24 };
25
26 static const EnumEntry<unsigned> UnwindOpInfo[] = {
27 { "RAX", 0 },
28 { "RCX", 1 },
29 { "RDX", 2 },
30 { "RBX", 3 },
31 { "RSP", 4 },
32 { "RBP", 5 },
33 { "RSI", 6 },
34 { "RDI", 7 },
35 { "R8", 8 },
36 { "R9", 9 },
37 { "R10", 10 },
38 { "R11", 11 },
39 { "R12", 12 },
40 { "R13", 13 },
41 { "R14", 14 },
42 { "R15", 15 }
43 };
44
getOffsetOfLSDA(const UnwindInfo & UI)45 static uint64_t getOffsetOfLSDA(const UnwindInfo& UI) {
46 return static_cast<const char*>(UI.getLanguageSpecificData())
47 - reinterpret_cast<const char*>(&UI);
48 }
49
getLargeSlotValue(ArrayRef<UnwindCode> UC)50 static uint32_t getLargeSlotValue(ArrayRef<UnwindCode> UC) {
51 if (UC.size() < 3)
52 return 0;
53 return UC[1].FrameOffset + (static_cast<uint32_t>(UC[2].FrameOffset) << 16);
54 }
55
56 // Returns the name of the unwind code.
getUnwindCodeTypeName(uint8_t Code)57 static StringRef getUnwindCodeTypeName(uint8_t Code) {
58 switch (Code) {
59 default: llvm_unreachable("Invalid unwind code");
60 case UOP_PushNonVol: return "PUSH_NONVOL";
61 case UOP_AllocLarge: return "ALLOC_LARGE";
62 case UOP_AllocSmall: return "ALLOC_SMALL";
63 case UOP_SetFPReg: return "SET_FPREG";
64 case UOP_SaveNonVol: return "SAVE_NONVOL";
65 case UOP_SaveNonVolBig: return "SAVE_NONVOL_FAR";
66 case UOP_SaveXMM128: return "SAVE_XMM128";
67 case UOP_SaveXMM128Big: return "SAVE_XMM128_FAR";
68 case UOP_PushMachFrame: return "PUSH_MACHFRAME";
69 }
70 }
71
72 // Returns the name of a referenced register.
getUnwindRegisterName(uint8_t Reg)73 static StringRef getUnwindRegisterName(uint8_t Reg) {
74 switch (Reg) {
75 default: llvm_unreachable("Invalid register");
76 case 0: return "RAX";
77 case 1: return "RCX";
78 case 2: return "RDX";
79 case 3: return "RBX";
80 case 4: return "RSP";
81 case 5: return "RBP";
82 case 6: return "RSI";
83 case 7: return "RDI";
84 case 8: return "R8";
85 case 9: return "R9";
86 case 10: return "R10";
87 case 11: return "R11";
88 case 12: return "R12";
89 case 13: return "R13";
90 case 14: return "R14";
91 case 15: return "R15";
92 }
93 }
94
95 // Calculates the number of array slots required for the unwind code.
getNumUsedSlots(const UnwindCode & UnwindCode)96 static unsigned getNumUsedSlots(const UnwindCode &UnwindCode) {
97 switch (UnwindCode.getUnwindOp()) {
98 default: llvm_unreachable("Invalid unwind code");
99 case UOP_PushNonVol:
100 case UOP_AllocSmall:
101 case UOP_SetFPReg:
102 case UOP_PushMachFrame:
103 return 1;
104 case UOP_SaveNonVol:
105 case UOP_SaveXMM128:
106 return 2;
107 case UOP_SaveNonVolBig:
108 case UOP_SaveXMM128Big:
109 return 3;
110 case UOP_AllocLarge:
111 return (UnwindCode.getOpInfo() == 0) ? 2 : 3;
112 }
113 }
114
formatSymbol(const Dumper::Context & Ctx,const coff_section * Section,uint64_t Offset,uint32_t Displacement)115 static std::string formatSymbol(const Dumper::Context &Ctx,
116 const coff_section *Section, uint64_t Offset,
117 uint32_t Displacement) {
118 std::string Buffer;
119 raw_string_ostream OS(Buffer);
120
121 StringRef Name;
122 SymbolRef Symbol;
123 if (Ctx.ResolveSymbol(Section, Offset, Symbol, Ctx.UserData) ||
124 Symbol.getName(Name)) {
125 OS << format(" (0x%" PRIX64 ")", Offset);
126 return OS.str();
127 }
128
129 OS << Name;
130 if (Displacement > 0)
131 OS << format(" +0x%X (0x%" PRIX64 ")", Displacement, Offset);
132 else
133 OS << format(" (0x%" PRIX64 ")", Offset);
134 return OS.str();
135 }
136
resolveRelocation(const Dumper::Context & Ctx,const coff_section * Section,uint64_t Offset,const coff_section * & ResolvedSection,uint64_t & ResolvedAddress)137 static std::error_code resolveRelocation(const Dumper::Context &Ctx,
138 const coff_section *Section,
139 uint64_t Offset,
140 const coff_section *&ResolvedSection,
141 uint64_t &ResolvedAddress) {
142 SymbolRef Symbol;
143 if (std::error_code EC =
144 Ctx.ResolveSymbol(Section, Offset, Symbol, Ctx.UserData))
145 return EC;
146
147 if (std::error_code EC = Symbol.getAddress(ResolvedAddress))
148 return EC;
149
150 section_iterator SI = Ctx.COFF.section_begin();
151 if (std::error_code EC = Symbol.getSection(SI))
152 return EC;
153
154 ResolvedSection = Ctx.COFF.getCOFFSection(*SI);
155 return object_error::success;
156 }
157
158 namespace llvm {
159 namespace Win64EH {
printRuntimeFunctionEntry(const Context & Ctx,const coff_section * Section,uint64_t Offset,const RuntimeFunction & RF)160 void Dumper::printRuntimeFunctionEntry(const Context &Ctx,
161 const coff_section *Section,
162 uint64_t Offset,
163 const RuntimeFunction &RF) {
164 SW.printString("StartAddress",
165 formatSymbol(Ctx, Section, Offset + 0, RF.StartAddress));
166 SW.printString("EndAddress",
167 formatSymbol(Ctx, Section, Offset + 4, RF.EndAddress));
168 SW.printString("UnwindInfoAddress",
169 formatSymbol(Ctx, Section, Offset + 8, RF.UnwindInfoOffset));
170 }
171
172 // Prints one unwind code. Because an unwind code can occupy up to 3 slots in
173 // the unwind codes array, this function requires that the correct number of
174 // slots is provided.
printUnwindCode(const UnwindInfo & UI,ArrayRef<UnwindCode> UC)175 void Dumper::printUnwindCode(const UnwindInfo& UI, ArrayRef<UnwindCode> UC) {
176 assert(UC.size() >= getNumUsedSlots(UC[0]));
177
178 SW.startLine() << format("0x%02X: ", unsigned(UC[0].u.CodeOffset))
179 << getUnwindCodeTypeName(UC[0].getUnwindOp());
180
181 switch (UC[0].getUnwindOp()) {
182 case UOP_PushNonVol:
183 OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo());
184 break;
185
186 case UOP_AllocLarge:
187 OS << " size="
188 << ((UC[0].getOpInfo() == 0) ? UC[1].FrameOffset * 8
189 : getLargeSlotValue(UC));
190 break;
191
192 case UOP_AllocSmall:
193 OS << " size=" << (UC[0].getOpInfo() + 1) * 8;
194 break;
195
196 case UOP_SetFPReg:
197 if (UI.getFrameRegister() == 0)
198 OS << " reg=<invalid>";
199 else
200 OS << " reg=" << getUnwindRegisterName(UI.getFrameRegister())
201 << format(", offset=0x%X", UI.getFrameOffset() * 16);
202 break;
203
204 case UOP_SaveNonVol:
205 OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo())
206 << format(", offset=0x%X", UC[1].FrameOffset * 8);
207 break;
208
209 case UOP_SaveNonVolBig:
210 OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo())
211 << format(", offset=0x%X", getLargeSlotValue(UC));
212 break;
213
214 case UOP_SaveXMM128:
215 OS << " reg=XMM" << static_cast<uint32_t>(UC[0].getOpInfo())
216 << format(", offset=0x%X", UC[1].FrameOffset * 16);
217 break;
218
219 case UOP_SaveXMM128Big:
220 OS << " reg=XMM" << static_cast<uint32_t>(UC[0].getOpInfo())
221 << format(", offset=0x%X", getLargeSlotValue(UC));
222 break;
223
224 case UOP_PushMachFrame:
225 OS << " errcode=" << (UC[0].getOpInfo() == 0 ? "no" : "yes");
226 break;
227 }
228
229 OS << "\n";
230 }
231
printUnwindInfo(const Context & Ctx,const coff_section * Section,off_t Offset,const UnwindInfo & UI)232 void Dumper::printUnwindInfo(const Context &Ctx, const coff_section *Section,
233 off_t Offset, const UnwindInfo &UI) {
234 DictScope UIS(SW, "UnwindInfo");
235 SW.printNumber("Version", UI.getVersion());
236 SW.printFlags("Flags", UI.getFlags(), makeArrayRef(UnwindFlags));
237 SW.printNumber("PrologSize", UI.PrologSize);
238 if (UI.getFrameRegister()) {
239 SW.printEnum("FrameRegister", UI.getFrameRegister(),
240 makeArrayRef(UnwindOpInfo));
241 SW.printHex("FrameOffset", UI.getFrameOffset());
242 } else {
243 SW.printString("FrameRegister", StringRef("-"));
244 SW.printString("FrameOffset", StringRef("-"));
245 }
246
247 SW.printNumber("UnwindCodeCount", UI.NumCodes);
248 {
249 ListScope UCS(SW, "UnwindCodes");
250 ArrayRef<UnwindCode> UC(&UI.UnwindCodes[0], UI.NumCodes);
251 for (const UnwindCode *UCI = UC.begin(), *UCE = UC.end(); UCI < UCE; ++UCI) {
252 unsigned UsedSlots = getNumUsedSlots(*UCI);
253 if (UsedSlots > UC.size()) {
254 errs() << "corrupt unwind data";
255 return;
256 }
257
258 printUnwindCode(UI, ArrayRef<UnwindCode>(UCI, UCE));
259 UCI = UCI + UsedSlots - 1;
260 }
261 }
262
263 uint64_t LSDAOffset = Offset + getOffsetOfLSDA(UI);
264 if (UI.getFlags() & (UNW_ExceptionHandler | UNW_TerminateHandler)) {
265 SW.printString("Handler",
266 formatSymbol(Ctx, Section, LSDAOffset,
267 UI.getLanguageSpecificHandlerOffset()));
268 } else if (UI.getFlags() & UNW_ChainInfo) {
269 if (const RuntimeFunction *Chained = UI.getChainedFunctionEntry()) {
270 DictScope CS(SW, "Chained");
271 printRuntimeFunctionEntry(Ctx, Section, LSDAOffset, *Chained);
272 }
273 }
274 }
275
printRuntimeFunction(const Context & Ctx,const coff_section * Section,uint64_t SectionOffset,const RuntimeFunction & RF)276 void Dumper::printRuntimeFunction(const Context &Ctx,
277 const coff_section *Section,
278 uint64_t SectionOffset,
279 const RuntimeFunction &RF) {
280 DictScope RFS(SW, "RuntimeFunction");
281 printRuntimeFunctionEntry(Ctx, Section, SectionOffset, RF);
282
283 const coff_section *XData;
284 uint64_t Offset;
285 if (error(resolveRelocation(Ctx, Section, SectionOffset + 8, XData, Offset)))
286 return;
287
288 ArrayRef<uint8_t> Contents;
289 if (error(Ctx.COFF.getSectionContents(XData, Contents)) || Contents.empty())
290 return;
291
292 Offset = Offset + RF.UnwindInfoOffset;
293 if (Offset > Contents.size())
294 return;
295
296 const auto UI = reinterpret_cast<const UnwindInfo*>(Contents.data() + Offset);
297 printUnwindInfo(Ctx, XData, Offset, *UI);
298 }
299
printData(const Context & Ctx)300 void Dumper::printData(const Context &Ctx) {
301 for (const auto &Section : Ctx.COFF.sections()) {
302 StringRef Name;
303 if (error(Section.getName(Name)))
304 continue;
305
306 if (Name != ".pdata" && !Name.startswith(".pdata$"))
307 continue;
308
309 const coff_section *PData = Ctx.COFF.getCOFFSection(Section);
310 ArrayRef<uint8_t> Contents;
311 if (error(Ctx.COFF.getSectionContents(PData, Contents)) || Contents.empty())
312 continue;
313
314 const RuntimeFunction *Entries =
315 reinterpret_cast<const RuntimeFunction *>(Contents.data());
316 const size_t Count = Contents.size() / sizeof(RuntimeFunction);
317 ArrayRef<RuntimeFunction> RuntimeFunctions(Entries, Count);
318
319 size_t Index = 0;
320 for (const auto &RF : RuntimeFunctions) {
321 printRuntimeFunction(Ctx, Ctx.COFF.getCOFFSection(Section),
322 Index * sizeof(RuntimeFunction), RF);
323 ++Index;
324 }
325 }
326 }
327 }
328 }
329
330