1 //===-- llvm/Support/ARMWinEH.h - Windows on ARM 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 #ifndef LLVM_SUPPORT_ARMWINEH_H 10 #define LLVM_SUPPORT_ARMWINEH_H 11 12 #include "llvm/ADT/ArrayRef.h" 13 #include "llvm/Support/Endian.h" 14 15 namespace llvm { 16 namespace ARM { 17 namespace WinEH { 18 enum class RuntimeFunctionFlag { 19 RFF_Unpacked, /// unpacked entry 20 RFF_Packed, /// packed entry 21 RFF_PackedFragment, /// packed entry representing a fragment 22 RFF_Reserved, /// reserved 23 }; 24 25 enum class ReturnType { 26 RT_POP, /// return via pop {pc} (L flag must be set) 27 RT_B, /// 16-bit branch 28 RT_BW, /// 32-bit branch 29 RT_NoEpilogue, /// no epilogue (fragment) 30 }; 31 32 /// RuntimeFunction - An entry in the table of procedure data (.pdata) 33 /// 34 /// This is ARM specific, but the Function Start RVA, Flag and 35 /// ExceptionInformationRVA fields work identically for ARM64. 36 /// 37 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 38 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 39 /// +---------------------------------------------------------------+ 40 /// | Function Start RVA | 41 /// +-------------------+-+-+-+-----+-+---+---------------------+---+ 42 /// | Stack Adjust |C|L|R| Reg |H|Ret| Function Length |Flg| 43 /// +-------------------+-+-+-+-----+-+---+---------------------+---+ 44 /// 45 /// Flag : 2-bit field with the following meanings: 46 /// - 00 = packed unwind data not used; reamining bits point to .xdata record 47 /// - 01 = packed unwind data 48 /// - 10 = packed unwind data, function assumed to have no prologue; useful 49 /// for function fragments that are discontiguous with the start of the 50 /// function 51 /// - 11 = reserved 52 /// Function Length : 11-bit field providing the length of the entire function 53 /// in bytes, divided by 2; if the function is greater than 54 /// 4KB, a full .xdata record must be used instead 55 /// Ret : 2-bit field indicating how the function returns 56 /// - 00 = return via pop {pc} (the L bit must be set) 57 /// - 01 = return via 16-bit branch 58 /// - 10 = return via 32-bit branch 59 /// - 11 = no epilogue; useful for function fragments that may only contain a 60 /// prologue but the epilogue is elsewhere 61 /// H : 1-bit flag indicating whether the function "homes" the integer parameter 62 /// registers (r0-r3), allocating 16-bytes on the stack 63 /// Reg : 3-bit field indicating the index of the last saved non-volatile 64 /// register. If the R bit is set to 0, then only integer registers are 65 /// saved (r4-rN, where N is 4 + Reg). If the R bit is set to 1, then 66 /// only floating-point registers are being saved (d8-dN, where N is 67 /// 8 + Reg). The special case of the R bit being set to 1 and Reg equal 68 /// to 7 indicates that no registers are saved. 69 /// R : 1-bit flag indicating whether the non-volatile registers are integer or 70 /// floating-point. 0 indicates integer, 1 indicates floating-point. The 71 /// special case of the R-flag being set and Reg being set to 7 indicates 72 /// that no non-volatile registers are saved. 73 /// L : 1-bit flag indicating whether the function saves/restores the link 74 /// register (LR) 75 /// C : 1-bit flag indicating whether the function includes extra instructions 76 /// to setup a frame chain for fast walking. If this flag is set, r11 is 77 /// implicitly added to the list of saved non-volatile integer registers. 78 /// Stack Adjust : 10-bit field indicating the number of bytes of stack that are 79 /// allocated for this function. Only values between 0x000 and 80 /// 0x3f3 can be directly encoded. If the value is 0x3f4 or 81 /// greater, then the low 4 bits have special meaning as follows: 82 /// - Bit 0-1 83 /// indicate the number of words' of adjustment (1-4), minus 1 84 /// - Bit 2 85 /// indicates if the prologue combined adjustment into push 86 /// - Bit 3 87 /// indicates if the epilogue combined adjustment into pop 88 /// 89 /// RESTRICTIONS: 90 /// - IF C is SET: 91 /// + L flag must be set since frame chaining requires r11 and lr 92 /// + r11 must NOT be included in the set of registers described by Reg 93 /// - IF Ret is 0: 94 /// + L flag must be set 95 96 // NOTE: RuntimeFunction is meant to be a simple class that provides raw access 97 // to all fields in the structure. The accessor methods reflect the names of 98 // the bitfields that they correspond to. Although some obvious simplifications 99 // are possible via merging of methods, it would prevent the use of this class 100 // to fully inspect the contents of the data structure which is particularly 101 // useful for scenarios such as llvm-readobj to aid in testing. 102 103 class RuntimeFunction { 104 public: 105 const support::ulittle32_t BeginAddress; 106 const support::ulittle32_t UnwindData; 107 108 RuntimeFunction(const support::ulittle32_t *Data) 109 : BeginAddress(Data[0]), UnwindData(Data[1]) {} 110 111 RuntimeFunction(const support::ulittle32_t BeginAddress, 112 const support::ulittle32_t UnwindData) 113 : BeginAddress(BeginAddress), UnwindData(UnwindData) {} 114 115 RuntimeFunctionFlag Flag() const { 116 return RuntimeFunctionFlag(UnwindData & 0x3); 117 } 118 119 uint32_t ExceptionInformationRVA() const { 120 assert(Flag() == RuntimeFunctionFlag::RFF_Unpacked && 121 "unpacked form required for this operation"); 122 return (UnwindData & ~0x3); 123 } 124 125 uint32_t PackedUnwindData() const { 126 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 127 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 128 "packed form required for this operation"); 129 return (UnwindData & ~0x3); 130 } 131 uint32_t FunctionLength() const { 132 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 133 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 134 "packed form required for this operation"); 135 return (((UnwindData & 0x00001ffc) >> 2) << 1); 136 } 137 ReturnType Ret() const { 138 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 139 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 140 "packed form required for this operation"); 141 assert(((UnwindData & 0x00006000) || L()) && "L must be set to 1"); 142 return ReturnType((UnwindData & 0x00006000) >> 13); 143 } 144 bool H() const { 145 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 146 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 147 "packed form required for this operation"); 148 return ((UnwindData & 0x00008000) >> 15); 149 } 150 uint8_t Reg() const { 151 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 152 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 153 "packed form required for this operation"); 154 return ((UnwindData & 0x00070000) >> 16); 155 } 156 bool R() const { 157 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 158 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 159 "packed form required for this operation"); 160 return ((UnwindData & 0x00080000) >> 19); 161 } 162 bool L() const { 163 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 164 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 165 "packed form required for this operation"); 166 return ((UnwindData & 0x00100000) >> 20); 167 } 168 bool C() const { 169 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 170 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 171 "packed form required for this operation"); 172 assert(((~UnwindData & 0x00200000) || L()) && 173 "L flag must be set, chaining requires r11 and LR"); 174 assert(((~UnwindData & 0x00200000) || (Reg() < 7) || R()) && 175 "r11 must not be included in Reg; C implies r11"); 176 return ((UnwindData & 0x00200000) >> 21); 177 } 178 uint16_t StackAdjust() const { 179 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 180 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 181 "packed form required for this operation"); 182 return ((UnwindData & 0xffc00000) >> 22); 183 } 184 }; 185 186 /// PrologueFolding - pseudo-flag derived from Stack Adjust indicating that the 187 /// prologue has stack adjustment combined into the push 188 inline bool PrologueFolding(const RuntimeFunction &RF) { 189 return RF.StackAdjust() >= 0x3f4 && (RF.StackAdjust() & 0x4); 190 } 191 /// Epilogue - pseudo-flag derived from Stack Adjust indicating that the 192 /// epilogue has stack adjustment combined into the pop 193 inline bool EpilogueFolding(const RuntimeFunction &RF) { 194 return RF.StackAdjust() >= 0x3f4 && (RF.StackAdjust() & 0x8); 195 } 196 /// StackAdjustment - calculated stack adjustment in words. The stack 197 /// adjustment should be determined via this function to account for the special 198 /// handling the special encoding when the value is >= 0x3f4. 199 inline uint16_t StackAdjustment(const RuntimeFunction &RF) { 200 uint16_t Adjustment = RF.StackAdjust(); 201 if (Adjustment >= 0x3f4) 202 return (Adjustment & 0x3) + 1; 203 return Adjustment; 204 } 205 206 /// SavedRegisterMask - Utility function to calculate the set of saved general 207 /// purpose (r0-r15) and VFP (d0-d31) registers. 208 std::pair<uint16_t, uint32_t> SavedRegisterMask(const RuntimeFunction &RF, 209 bool Prologue = true); 210 211 /// RuntimeFunctionARM64 - An entry in the table of procedure data (.pdata) 212 /// 213 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 214 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 215 /// +---------------------------------------------------------------+ 216 /// | Function Start RVA | 217 /// +-----------------+---+-+-------+-----+---------------------+---+ 218 /// | Frame Size |CR |H| RegI |RegF | Function Length |Flg| 219 /// +-----------------+---+-+-------+-----+---------------------+---+ 220 /// 221 /// See https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling 222 /// for the full reference for this struct. 223 224 class RuntimeFunctionARM64 { 225 public: 226 const support::ulittle32_t BeginAddress; 227 const support::ulittle32_t UnwindData; 228 229 RuntimeFunctionARM64(const support::ulittle32_t *Data) 230 : BeginAddress(Data[0]), UnwindData(Data[1]) {} 231 232 RuntimeFunctionARM64(const support::ulittle32_t BeginAddress, 233 const support::ulittle32_t UnwindData) 234 : BeginAddress(BeginAddress), UnwindData(UnwindData) {} 235 236 RuntimeFunctionFlag Flag() const { 237 return RuntimeFunctionFlag(UnwindData & 0x3); 238 } 239 240 uint32_t ExceptionInformationRVA() const { 241 assert(Flag() == RuntimeFunctionFlag::RFF_Unpacked && 242 "unpacked form required for this operation"); 243 return (UnwindData & ~0x3); 244 } 245 246 uint32_t PackedUnwindData() const { 247 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 248 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 249 "packed form required for this operation"); 250 return (UnwindData & ~0x3); 251 } 252 uint32_t FunctionLength() const { 253 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 254 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 255 "packed form required for this operation"); 256 return (((UnwindData & 0x00001ffc) >> 2) << 2); 257 } 258 uint8_t RegF() const { 259 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 260 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 261 "packed form required for this operation"); 262 return ((UnwindData & 0x0000e000) >> 13); 263 } 264 uint8_t RegI() const { 265 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 266 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 267 "packed form required for this operation"); 268 return ((UnwindData & 0x000f0000) >> 16); 269 } 270 bool H() const { 271 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 272 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 273 "packed form required for this operation"); 274 return ((UnwindData & 0x00100000) >> 20); 275 } 276 uint8_t CR() const { 277 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 278 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 279 "packed form required for this operation"); 280 return ((UnwindData & 0x600000) >> 21); 281 } 282 uint16_t FrameSize() const { 283 assert((Flag() == RuntimeFunctionFlag::RFF_Packed || 284 Flag() == RuntimeFunctionFlag::RFF_PackedFragment) && 285 "packed form required for this operation"); 286 return ((UnwindData & 0xff800000) >> 23); 287 } 288 }; 289 290 /// ExceptionDataRecord - An entry in the table of exception data (.xdata) 291 /// 292 /// The format on ARM is: 293 /// 294 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 295 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 296 /// +-------+---------+-+-+-+---+-----------------------------------+ 297 /// | C Wrd | Epi Cnt |F|E|X|Ver| Function Length | 298 /// +-------+--------+'-'-'-'---'---+-------------------------------+ 299 /// | Reserved |Ex. Code Words| (Extended Epilogue Count) | 300 /// +-------+--------+--------------+-------------------------------+ 301 /// 302 /// The format on ARM64 is: 303 /// 304 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 305 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 306 /// +---------+---------+-+-+---+-----------------------------------+ 307 /// | C Wrd | Epi Cnt |E|X|Ver| Function Length | 308 /// +---------+------+--'-'-'---'---+-------------------------------+ 309 /// | Reserved |Ex. Code Words| (Extended Epilogue Count) | 310 /// +-------+--------+--------------+-------------------------------+ 311 /// 312 /// Function Length : 18-bit field indicating the total length of the function 313 /// in bytes divided by 2. If a function is larger than 314 /// 512KB, then multiple pdata and xdata records must be used. 315 /// Vers : 2-bit field describing the version of the remaining structure. Only 316 /// version 0 is currently defined (values 1-3 are not permitted). 317 /// X : 1-bit field indicating the presence of exception data 318 /// E : 1-bit field indicating that the single epilogue is packed into the 319 /// header 320 /// F : 1-bit field indicating that the record describes a function fragment 321 /// (implies that no prologue is present, and prologue processing should be 322 /// skipped) (ARM only) 323 /// Epilogue Count : 5-bit field that differs in meaning based on the E field. 324 /// 325 /// If E is set, then this field specifies the index of the 326 /// first unwind code describing the (only) epilogue. 327 /// 328 /// Otherwise, this field indicates the number of exception 329 /// scopes. If more than 31 scopes exist, then this field and 330 /// the Code Words field must both be set to 0 to indicate that 331 /// an extension word is required. 332 /// Code Words : 4-bit (5-bit on ARM64) field that specifies the number of 333 /// 32-bit words needed to contain all the unwind codes. If more 334 /// than 15 words (31 words on ARM64) are required, then this field 335 /// and the Epilogue Count field must both be set to 0 to indicate 336 /// that an extension word is required. 337 /// Extended Epilogue Count, Extended Code Words : 338 /// Valid only if Epilog Count and Code Words are both 339 /// set to 0. Provides an 8-bit extended code word 340 /// count and 16-bits for epilogue count 341 /// 342 /// The epilogue scope format on ARM is: 343 /// 344 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 345 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 346 /// +----------------+------+---+---+-------------------------------+ 347 /// | Ep Start Idx | Cond |Res| Epilogue Start Offset | 348 /// +----------------+------+---+-----------------------------------+ 349 /// 350 /// The epilogue scope format on ARM64 is: 351 /// 352 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 353 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 354 /// +-------------------+-------+---+-------------------------------+ 355 /// | Ep Start Idx | Res | Epilogue Start Offset | 356 /// +-------------------+-------+-----------------------------------+ 357 /// 358 /// If the E bit is unset in the header, the header is followed by a series of 359 /// epilogue scopes, which are sorted by their offset. 360 /// 361 /// Epilogue Start Offset: 18-bit field encoding the offset of epilogue relative 362 /// to the start of the function in bytes divided by two 363 /// Res : 2-bit field reserved for future expansion (must be set to 0) 364 /// Condition : (ARM only) 4-bit field providing the condition under which the 365 /// epilogue is executed. Unconditional epilogues should set this 366 /// field to 0xe. Epilogues must be entirely conditional or 367 /// unconditional, and in Thumb-2 mode. The epilogue begins with 368 /// the first instruction after the IT opcode. 369 /// Epilogue Start Index : 8-bit field indicating the byte index of the first 370 /// unwind code describing the epilogue 371 /// 372 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 373 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 374 /// +---------------+---------------+---------------+---------------+ 375 /// | Unwind Code 3 | Unwind Code 2 | Unwind Code 1 | Unwind Code 0 | 376 /// +---------------+---------------+---------------+---------------+ 377 /// 378 /// Following the epilogue scopes, the byte code describing the unwinding 379 /// follows. This is padded to align up to word alignment. Bytes are stored in 380 /// little endian. 381 /// 382 /// 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 383 /// 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 384 /// +---------------------------------------------------------------+ 385 /// | Exception Handler RVA (requires X = 1) | 386 /// +---------------------------------------------------------------+ 387 /// | (possibly followed by data required for exception handler) | 388 /// +---------------------------------------------------------------+ 389 /// 390 /// If the X bit is set in the header, the unwind byte code is followed by the 391 /// exception handler information. This constants of one Exception Handler RVA 392 /// which is the address to the exception handler, followed immediately by the 393 /// variable length data associated with the exception handler. 394 /// 395 396 struct EpilogueScope { 397 const support::ulittle32_t ES; 398 399 EpilogueScope(const support::ulittle32_t Data) : ES(Data) {} 400 // Same for both ARM and AArch64. 401 uint32_t EpilogueStartOffset() const { 402 return (ES & 0x0003ffff); 403 } 404 405 // Different implementations for ARM and AArch64. 406 uint8_t ResARM() const { 407 return ((ES & 0x000c0000) >> 18); 408 } 409 410 uint8_t ResAArch64() const { 411 return ((ES & 0x000f0000) >> 18); 412 } 413 414 // Condition is only applicable to ARM. 415 uint8_t Condition() const { 416 return ((ES & 0x00f00000) >> 20); 417 } 418 419 // Different implementations for ARM and AArch64. 420 uint8_t EpilogueStartIndexARM() const { 421 return ((ES & 0xff000000) >> 24); 422 } 423 424 uint16_t EpilogueStartIndexAArch64() const { 425 return ((ES & 0xffc00000) >> 22); 426 } 427 }; 428 429 struct ExceptionDataRecord; 430 inline size_t HeaderWords(const ExceptionDataRecord &XR); 431 432 struct ExceptionDataRecord { 433 const support::ulittle32_t *Data; 434 bool isAArch64; 435 436 ExceptionDataRecord(const support::ulittle32_t *Data, bool isAArch64) : 437 Data(Data), isAArch64(isAArch64) {} 438 439 uint32_t FunctionLength() const { 440 return (Data[0] & 0x0003ffff); 441 } 442 443 uint32_t FunctionLengthInBytesARM() const { 444 return FunctionLength() << 1; 445 } 446 447 uint32_t FunctionLengthInBytesAArch64() const { 448 return FunctionLength() << 2; 449 } 450 451 uint8_t Vers() const { 452 return (Data[0] & 0x000C0000) >> 18; 453 } 454 455 bool X() const { 456 return ((Data[0] & 0x00100000) >> 20); 457 } 458 459 bool E() const { 460 return ((Data[0] & 0x00200000) >> 21); 461 } 462 463 bool F() const { 464 assert(!isAArch64 && "Fragments are only supported on ARMv7 WinEH"); 465 return ((Data[0] & 0x00400000) >> 22); 466 } 467 468 uint16_t EpilogueCount() const { 469 if (HeaderWords(*this) == 1) { 470 if (isAArch64) 471 return (Data[0] & 0x07C00000) >> 22; 472 return (Data[0] & 0x0f800000) >> 23; 473 } 474 return Data[1] & 0x0000ffff; 475 } 476 477 uint8_t CodeWords() const { 478 if (HeaderWords(*this) == 1) { 479 if (isAArch64) 480 return (Data[0] & 0xf8000000) >> 27; 481 return (Data[0] & 0xf0000000) >> 28; 482 } 483 return (Data[1] & 0x00ff0000) >> 16; 484 } 485 486 ArrayRef<support::ulittle32_t> EpilogueScopes() const { 487 assert(E() == 0 && "epilogue scopes are only present when the E bit is 0"); 488 size_t Offset = HeaderWords(*this); 489 return makeArrayRef(&Data[Offset], EpilogueCount()); 490 } 491 492 ArrayRef<uint8_t> UnwindByteCode() const { 493 const size_t Offset = HeaderWords(*this) 494 + (E() ? 0 : EpilogueCount()); 495 const uint8_t *ByteCode = 496 reinterpret_cast<const uint8_t *>(&Data[Offset]); 497 return makeArrayRef(ByteCode, CodeWords() * sizeof(uint32_t)); 498 } 499 500 uint32_t ExceptionHandlerRVA() const { 501 assert(X() && "Exception Handler RVA is only valid if the X bit is set"); 502 return Data[HeaderWords(*this) + (E() ? 0 : EpilogueCount()) + CodeWords()]; 503 } 504 505 uint32_t ExceptionHandlerParameter() const { 506 assert(X() && "Exception Handler RVA is only valid if the X bit is set"); 507 return Data[HeaderWords(*this) + (E() ? 0 : EpilogueCount()) + CodeWords() + 508 1]; 509 } 510 }; 511 512 inline size_t HeaderWords(const ExceptionDataRecord &XR) { 513 if (XR.isAArch64) 514 return (XR.Data[0] & 0xffc00000) ? 1 : 2; 515 return (XR.Data[0] & 0xff800000) ? 1 : 2; 516 } 517 } 518 } 519 } 520 521 #endif 522