1 //===------- ELF_riscv.cpp -JIT linker implementation for ELF/riscv -------===// 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 // ELF/riscv jit-link implementation. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/ExecutionEngine/JITLink/ELF_riscv.h" 14 #include "ELFLinkGraphBuilder.h" 15 #include "JITLinkGeneric.h" 16 #include "PerGraphGOTAndPLTStubsBuilder.h" 17 #include "llvm/BinaryFormat/ELF.h" 18 #include "llvm/ExecutionEngine/JITLink/JITLink.h" 19 #include "llvm/ExecutionEngine/JITLink/riscv.h" 20 #include "llvm/Object/ELF.h" 21 #include "llvm/Object/ELFObjectFile.h" 22 #include "llvm/Support/Endian.h" 23 24 #define DEBUG_TYPE "jitlink" 25 using namespace llvm; 26 using namespace llvm::jitlink; 27 using namespace llvm::jitlink::riscv; 28 29 namespace { 30 31 class PerGraphGOTAndPLTStubsBuilder_ELF_riscv 32 : public PerGraphGOTAndPLTStubsBuilder< 33 PerGraphGOTAndPLTStubsBuilder_ELF_riscv> { 34 public: 35 static constexpr size_t StubEntrySize = 16; 36 static const uint8_t NullGOTEntryContent[8]; 37 static const uint8_t RV64StubContent[StubEntrySize]; 38 static const uint8_t RV32StubContent[StubEntrySize]; 39 40 using PerGraphGOTAndPLTStubsBuilder< 41 PerGraphGOTAndPLTStubsBuilder_ELF_riscv>::PerGraphGOTAndPLTStubsBuilder; 42 43 bool isRV64() const { return G.getPointerSize() == 8; } 44 45 bool isGOTEdgeToFix(Edge &E) const { return E.getKind() == R_RISCV_GOT_HI20; } 46 47 Symbol &createGOTEntry(Symbol &Target) { 48 Block &GOTBlock = 49 G.createContentBlock(getGOTSection(), getGOTEntryBlockContent(), 50 orc::ExecutorAddr(), G.getPointerSize(), 0); 51 GOTBlock.addEdge(isRV64() ? R_RISCV_64 : R_RISCV_32, 0, Target, 0); 52 return G.addAnonymousSymbol(GOTBlock, 0, G.getPointerSize(), false, false); 53 } 54 55 Symbol &createPLTStub(Symbol &Target) { 56 Block &StubContentBlock = G.createContentBlock( 57 getStubsSection(), getStubBlockContent(), orc::ExecutorAddr(), 4, 0); 58 auto &GOTEntrySymbol = getGOTEntry(Target); 59 StubContentBlock.addEdge(R_RISCV_CALL, 0, GOTEntrySymbol, 0); 60 return G.addAnonymousSymbol(StubContentBlock, 0, StubEntrySize, true, 61 false); 62 } 63 64 void fixGOTEdge(Edge &E, Symbol &GOTEntry) { 65 // Replace the relocation pair (R_RISCV_GOT_HI20, R_RISCV_PCREL_LO12) 66 // with (R_RISCV_PCREL_HI20, R_RISCV_PCREL_LO12) 67 // Therefore, here just change the R_RISCV_GOT_HI20 to R_RISCV_PCREL_HI20 68 E.setKind(R_RISCV_PCREL_HI20); 69 E.setTarget(GOTEntry); 70 } 71 72 void fixPLTEdge(Edge &E, Symbol &PLTStubs) { 73 assert(E.getKind() == R_RISCV_CALL_PLT && "Not a R_RISCV_CALL_PLT edge?"); 74 E.setKind(R_RISCV_CALL); 75 E.setTarget(PLTStubs); 76 } 77 78 bool isExternalBranchEdge(Edge &E) const { 79 return E.getKind() == R_RISCV_CALL_PLT; 80 } 81 82 private: 83 Section &getGOTSection() const { 84 if (!GOTSection) 85 GOTSection = &G.createSection("$__GOT", orc::MemProt::Read); 86 return *GOTSection; 87 } 88 89 Section &getStubsSection() const { 90 if (!StubsSection) 91 StubsSection = 92 &G.createSection("$__STUBS", orc::MemProt::Read | orc::MemProt::Exec); 93 return *StubsSection; 94 } 95 96 ArrayRef<char> getGOTEntryBlockContent() { 97 return {reinterpret_cast<const char *>(NullGOTEntryContent), 98 G.getPointerSize()}; 99 } 100 101 ArrayRef<char> getStubBlockContent() { 102 auto StubContent = isRV64() ? RV64StubContent : RV32StubContent; 103 return {reinterpret_cast<const char *>(StubContent), StubEntrySize}; 104 } 105 106 mutable Section *GOTSection = nullptr; 107 mutable Section *StubsSection = nullptr; 108 }; 109 110 const uint8_t PerGraphGOTAndPLTStubsBuilder_ELF_riscv::NullGOTEntryContent[8] = 111 {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}; 112 113 const uint8_t 114 PerGraphGOTAndPLTStubsBuilder_ELF_riscv::RV64StubContent[StubEntrySize] = { 115 0x17, 0x0e, 0x00, 0x00, // auipc t3, literal 116 0x03, 0x3e, 0x0e, 0x00, // ld t3, literal(t3) 117 0x67, 0x00, 0x0e, 0x00, // jr t3 118 0x13, 0x00, 0x00, 0x00}; // nop 119 120 const uint8_t 121 PerGraphGOTAndPLTStubsBuilder_ELF_riscv::RV32StubContent[StubEntrySize] = { 122 0x17, 0x0e, 0x00, 0x00, // auipc t3, literal 123 0x03, 0x2e, 0x0e, 0x00, // lw t3, literal(t3) 124 0x67, 0x00, 0x0e, 0x00, // jr t3 125 0x13, 0x00, 0x00, 0x00}; // nop 126 } // namespace 127 namespace llvm { 128 namespace jitlink { 129 130 static Expected<const Edge &> getRISCVPCRelHi20(const Edge &E) { 131 using namespace riscv; 132 assert((E.getKind() == R_RISCV_PCREL_LO12_I || 133 E.getKind() == R_RISCV_PCREL_LO12_S) && 134 "Can only have high relocation for R_RISCV_PCREL_LO12_I or " 135 "R_RISCV_PCREL_LO12_S"); 136 137 const Symbol &Sym = E.getTarget(); 138 const Block &B = Sym.getBlock(); 139 orc::ExecutorAddrDiff Offset = Sym.getOffset(); 140 141 struct Comp { 142 bool operator()(const Edge &Lhs, orc::ExecutorAddrDiff Offset) { 143 return Lhs.getOffset() < Offset; 144 } 145 bool operator()(orc::ExecutorAddrDiff Offset, const Edge &Rhs) { 146 return Offset < Rhs.getOffset(); 147 } 148 }; 149 150 auto Bound = 151 std::equal_range(B.edges().begin(), B.edges().end(), Offset, Comp{}); 152 153 for (auto It = Bound.first; It != Bound.second; ++It) { 154 if (It->getKind() == R_RISCV_PCREL_HI20) 155 return *It; 156 } 157 158 return make_error<JITLinkError>( 159 "No HI20 PCREL relocation type be found for LO12 PCREL relocation type"); 160 } 161 162 static uint32_t extractBits(uint32_t Num, unsigned Low, unsigned Size) { 163 return (Num & (((1ULL << Size) - 1) << Low)) >> Low; 164 } 165 166 static inline bool isAlignmentCorrect(uint64_t Value, int N) { 167 return (Value & (N - 1)) ? false : true; 168 } 169 170 // Requires 0 < N <= 64. 171 static inline bool isInRangeForImm(int64_t Value, int N) { 172 return Value == llvm::SignExtend64(Value, N); 173 } 174 175 class ELFJITLinker_riscv : public JITLinker<ELFJITLinker_riscv> { 176 friend class JITLinker<ELFJITLinker_riscv>; 177 178 public: 179 ELFJITLinker_riscv(std::unique_ptr<JITLinkContext> Ctx, 180 std::unique_ptr<LinkGraph> G, PassConfiguration PassConfig) 181 : JITLinker(std::move(Ctx), std::move(G), std::move(PassConfig)) {} 182 183 private: 184 Error applyFixup(LinkGraph &G, Block &B, const Edge &E) const { 185 using namespace riscv; 186 using namespace llvm::support; 187 188 char *BlockWorkingMem = B.getAlreadyMutableContent().data(); 189 char *FixupPtr = BlockWorkingMem + E.getOffset(); 190 orc::ExecutorAddr FixupAddress = B.getAddress() + E.getOffset(); 191 switch (E.getKind()) { 192 case R_RISCV_32: { 193 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 194 *(little32_t *)FixupPtr = static_cast<uint32_t>(Value); 195 break; 196 } 197 case R_RISCV_64: { 198 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 199 *(little64_t *)FixupPtr = static_cast<uint64_t>(Value); 200 break; 201 } 202 case R_RISCV_BRANCH: { 203 int64_t Value = E.getTarget().getAddress() + E.getAddend() - FixupAddress; 204 if (LLVM_UNLIKELY(!isInRangeForImm(Value >> 1, 12))) 205 return makeTargetOutOfRangeError(G, B, E); 206 if (LLVM_UNLIKELY(!isAlignmentCorrect(Value, 2))) 207 return makeAlignmentError(FixupAddress, Value, 2, E); 208 uint32_t Imm31_25 = 209 extractBits(Value, 5, 6) << 25 | extractBits(Value, 12, 1) << 31; 210 uint32_t Imm11_7 = 211 extractBits(Value, 1, 4) << 8 | extractBits(Value, 11, 1) << 7; 212 uint32_t RawInstr = *(little32_t *)FixupPtr; 213 *(little32_t *)FixupPtr = (RawInstr & 0x1FFF07F) | Imm31_25 | Imm11_7; 214 break; 215 } 216 case R_RISCV_JAL: { 217 int64_t Value = E.getTarget().getAddress() + E.getAddend() - FixupAddress; 218 if (LLVM_UNLIKELY(!isInRangeForImm(Value >> 1, 20))) 219 return makeTargetOutOfRangeError(G, B, E); 220 if (LLVM_UNLIKELY(!isAlignmentCorrect(Value, 2))) 221 return makeAlignmentError(FixupAddress, Value, 2, E); 222 uint32_t Imm20 = extractBits(Value, 20, 1) << 31; 223 uint32_t Imm10_1 = extractBits(Value, 1, 10) << 21; 224 uint32_t Imm11 = extractBits(Value, 11, 1) << 20; 225 uint32_t Imm19_12 = extractBits(Value, 12, 8) << 12; 226 uint32_t RawInstr = *(little32_t *)FixupPtr; 227 *(little32_t *)FixupPtr = RawInstr | Imm20 | Imm10_1 | Imm11 | Imm19_12; 228 break; 229 } 230 case R_RISCV_CALL: { 231 int64_t Value = E.getTarget().getAddress() + E.getAddend() - FixupAddress; 232 int64_t Hi = Value + 0x800; 233 if (LLVM_UNLIKELY(!isInRangeForImm(Hi, 32))) 234 return makeTargetOutOfRangeError(G, B, E); 235 int32_t Lo = Value & 0xFFF; 236 uint32_t RawInstrAuipc = *(little32_t *)FixupPtr; 237 uint32_t RawInstrJalr = *(little32_t *)(FixupPtr + 4); 238 *(little32_t *)FixupPtr = 239 RawInstrAuipc | (static_cast<uint32_t>(Hi & 0xFFFFF000)); 240 *(little32_t *)(FixupPtr + 4) = 241 RawInstrJalr | (static_cast<uint32_t>(Lo) << 20); 242 break; 243 } 244 // The relocations R_RISCV_CALL_PLT and R_RISCV_GOT_HI20 are handled by 245 // PerGraphGOTAndPLTStubsBuilder_ELF_riscv and are transformed into 246 // R_RISCV_CALL and R_RISCV_PCREL_HI20. 247 case R_RISCV_PCREL_HI20: { 248 int64_t Value = E.getTarget().getAddress() + E.getAddend() - FixupAddress; 249 int64_t Hi = Value + 0x800; 250 if (LLVM_UNLIKELY(!isInRangeForImm(Hi, 32))) 251 return makeTargetOutOfRangeError(G, B, E); 252 uint32_t RawInstr = *(little32_t *)FixupPtr; 253 *(little32_t *)FixupPtr = 254 (RawInstr & 0xFFF) | (static_cast<uint32_t>(Hi & 0xFFFFF000)); 255 break; 256 } 257 case R_RISCV_PCREL_LO12_I: { 258 // FIXME: We assume that R_RISCV_PCREL_HI20 is present in object code and 259 // pairs with current relocation R_RISCV_PCREL_LO12_I. So here may need a 260 // check. 261 auto RelHI20 = getRISCVPCRelHi20(E); 262 if (!RelHI20) 263 return RelHI20.takeError(); 264 int64_t Value = RelHI20->getTarget().getAddress() + 265 RelHI20->getAddend() - E.getTarget().getAddress(); 266 int64_t Lo = Value & 0xFFF; 267 uint32_t RawInstr = *(little32_t *)FixupPtr; 268 *(little32_t *)FixupPtr = 269 (RawInstr & 0xFFFFF) | (static_cast<uint32_t>(Lo & 0xFFF) << 20); 270 break; 271 } 272 case R_RISCV_PCREL_LO12_S: { 273 // FIXME: We assume that R_RISCV_PCREL_HI20 is present in object code and 274 // pairs with current relocation R_RISCV_PCREL_LO12_S. So here may need a 275 // check. 276 auto RelHI20 = getRISCVPCRelHi20(E); 277 if (!RelHI20) 278 return RelHI20.takeError(); 279 int64_t Value = RelHI20->getTarget().getAddress() + 280 RelHI20->getAddend() - E.getTarget().getAddress(); 281 int64_t Lo = Value & 0xFFF; 282 uint32_t Imm31_25 = extractBits(Lo, 5, 7) << 25; 283 uint32_t Imm11_7 = extractBits(Lo, 0, 5) << 7; 284 uint32_t RawInstr = *(little32_t *)FixupPtr; 285 286 *(little32_t *)FixupPtr = (RawInstr & 0x1FFF07F) | Imm31_25 | Imm11_7; 287 break; 288 } 289 case R_RISCV_HI20: { 290 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 291 int64_t Hi = Value + 0x800; 292 if (LLVM_UNLIKELY(!isInRangeForImm(Hi, 32))) 293 return makeTargetOutOfRangeError(G, B, E); 294 uint32_t RawInstr = *(little32_t *)FixupPtr; 295 *(little32_t *)FixupPtr = 296 (RawInstr & 0xFFF) | (static_cast<uint32_t>(Hi & 0xFFFFF000)); 297 break; 298 } 299 case R_RISCV_LO12_I: { 300 // FIXME: We assume that R_RISCV_HI20 is present in object code and pairs 301 // with current relocation R_RISCV_LO12_I. So here may need a check. 302 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 303 int32_t Lo = Value & 0xFFF; 304 uint32_t RawInstr = *(little32_t *)FixupPtr; 305 *(little32_t *)FixupPtr = 306 (RawInstr & 0xFFFFF) | (static_cast<uint32_t>(Lo & 0xFFF) << 20); 307 break; 308 } 309 case R_RISCV_LO12_S: { 310 // FIXME: We assume that R_RISCV_HI20 is present in object code and pairs 311 // with current relocation R_RISCV_LO12_S. So here may need a check. 312 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 313 int64_t Lo = Value & 0xFFF; 314 uint32_t Imm31_25 = extractBits(Lo, 5, 7) << 25; 315 uint32_t Imm11_7 = extractBits(Lo, 0, 5) << 7; 316 uint32_t RawInstr = *(little32_t *)FixupPtr; 317 *(little32_t *)FixupPtr = (RawInstr & 0x1FFF07F) | Imm31_25 | Imm11_7; 318 break; 319 } 320 case R_RISCV_ADD8: { 321 int64_t Value = 322 (E.getTarget().getAddress() + 323 *(reinterpret_cast<const uint8_t *>(FixupAddress.getValue())) + 324 E.getAddend()) 325 .getValue(); 326 *FixupPtr = static_cast<uint8_t>(Value); 327 break; 328 } 329 case R_RISCV_ADD16: { 330 int64_t Value = (E.getTarget().getAddress() + 331 support::endian::read16le(reinterpret_cast<const void *>( 332 FixupAddress.getValue())) + 333 E.getAddend()) 334 .getValue(); 335 *(little16_t *)FixupPtr = static_cast<uint16_t>(Value); 336 break; 337 } 338 case R_RISCV_ADD32: { 339 int64_t Value = (E.getTarget().getAddress() + 340 support::endian::read32le(reinterpret_cast<const void *>( 341 FixupAddress.getValue())) + 342 E.getAddend()) 343 .getValue(); 344 *(little32_t *)FixupPtr = static_cast<uint32_t>(Value); 345 break; 346 } 347 case R_RISCV_ADD64: { 348 int64_t Value = (E.getTarget().getAddress() + 349 support::endian::read64le(reinterpret_cast<const void *>( 350 FixupAddress.getValue())) + 351 E.getAddend()) 352 .getValue(); 353 *(little64_t *)FixupPtr = static_cast<uint64_t>(Value); 354 break; 355 } 356 case R_RISCV_SUB8: { 357 int64_t Value = 358 *(reinterpret_cast<const uint8_t *>(FixupAddress.getValue())) - 359 E.getTarget().getAddress().getValue() - E.getAddend(); 360 *FixupPtr = static_cast<uint8_t>(Value); 361 break; 362 } 363 case R_RISCV_SUB16: { 364 int64_t Value = support::endian::read16le(reinterpret_cast<const void *>( 365 FixupAddress.getValue())) - 366 E.getTarget().getAddress().getValue() - E.getAddend(); 367 *(little16_t *)FixupPtr = static_cast<uint32_t>(Value); 368 break; 369 } 370 case R_RISCV_SUB32: { 371 int64_t Value = support::endian::read32le(reinterpret_cast<const void *>( 372 FixupAddress.getValue())) - 373 E.getTarget().getAddress().getValue() - E.getAddend(); 374 *(little32_t *)FixupPtr = static_cast<uint32_t>(Value); 375 break; 376 } 377 case R_RISCV_SUB64: { 378 int64_t Value = support::endian::read64le(reinterpret_cast<const void *>( 379 FixupAddress.getValue())) - 380 E.getTarget().getAddress().getValue() - E.getAddend(); 381 *(little64_t *)FixupPtr = static_cast<uint64_t>(Value); 382 break; 383 } 384 case R_RISCV_SUB6: { 385 int64_t Value = 386 *(reinterpret_cast<const uint8_t *>(FixupAddress.getValue())) & 0x3f; 387 Value -= E.getTarget().getAddress().getValue() - E.getAddend(); 388 *FixupPtr = (*FixupPtr & 0xc0) | (static_cast<uint8_t>(Value) & 0x3f); 389 break; 390 } 391 case R_RISCV_SET6: { 392 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 393 uint32_t RawData = *(little32_t *)FixupPtr; 394 int64_t Word6 = Value & 0x3f; 395 *(little32_t *)FixupPtr = (RawData & 0xffffffc0) | Word6; 396 break; 397 } 398 case R_RISCV_SET8: { 399 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 400 uint32_t RawData = *(little32_t *)FixupPtr; 401 int64_t Word8 = Value & 0xff; 402 *(little32_t *)FixupPtr = (RawData & 0xffffff00) | Word8; 403 break; 404 } 405 case R_RISCV_SET16: { 406 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 407 uint32_t RawData = *(little32_t *)FixupPtr; 408 int64_t Word16 = Value & 0xffff; 409 *(little32_t *)FixupPtr = (RawData & 0xffff0000) | Word16; 410 break; 411 } 412 case R_RISCV_SET32: { 413 int64_t Value = (E.getTarget().getAddress() + E.getAddend()).getValue(); 414 int64_t Word32 = Value & 0xffffffff; 415 *(little32_t *)FixupPtr = Word32; 416 break; 417 } 418 case R_RISCV_32_PCREL: { 419 int64_t Value = E.getTarget().getAddress() + E.getAddend() - FixupAddress; 420 int64_t Word32 = Value & 0xffffffff; 421 *(little32_t *)FixupPtr = Word32; 422 break; 423 } 424 } 425 return Error::success(); 426 } 427 }; 428 429 template <typename ELFT> 430 class ELFLinkGraphBuilder_riscv : public ELFLinkGraphBuilder<ELFT> { 431 private: 432 static Expected<riscv::EdgeKind_riscv> 433 getRelocationKind(const uint32_t Type) { 434 using namespace riscv; 435 switch (Type) { 436 case ELF::R_RISCV_32: 437 return EdgeKind_riscv::R_RISCV_32; 438 case ELF::R_RISCV_64: 439 return EdgeKind_riscv::R_RISCV_64; 440 case ELF::R_RISCV_BRANCH: 441 return EdgeKind_riscv::R_RISCV_BRANCH; 442 case ELF::R_RISCV_JAL: 443 return EdgeKind_riscv::R_RISCV_JAL; 444 case ELF::R_RISCV_CALL: 445 return EdgeKind_riscv::R_RISCV_CALL; 446 case ELF::R_RISCV_CALL_PLT: 447 return EdgeKind_riscv::R_RISCV_CALL_PLT; 448 case ELF::R_RISCV_GOT_HI20: 449 return EdgeKind_riscv::R_RISCV_GOT_HI20; 450 case ELF::R_RISCV_PCREL_HI20: 451 return EdgeKind_riscv::R_RISCV_PCREL_HI20; 452 case ELF::R_RISCV_PCREL_LO12_I: 453 return EdgeKind_riscv::R_RISCV_PCREL_LO12_I; 454 case ELF::R_RISCV_PCREL_LO12_S: 455 return EdgeKind_riscv::R_RISCV_PCREL_LO12_S; 456 case ELF::R_RISCV_HI20: 457 return EdgeKind_riscv::R_RISCV_HI20; 458 case ELF::R_RISCV_LO12_I: 459 return EdgeKind_riscv::R_RISCV_LO12_I; 460 case ELF::R_RISCV_LO12_S: 461 return EdgeKind_riscv::R_RISCV_LO12_S; 462 case ELF::R_RISCV_ADD8: 463 return EdgeKind_riscv::R_RISCV_ADD8; 464 case ELF::R_RISCV_ADD16: 465 return EdgeKind_riscv::R_RISCV_ADD16; 466 case ELF::R_RISCV_ADD32: 467 return EdgeKind_riscv::R_RISCV_ADD32; 468 case ELF::R_RISCV_ADD64: 469 return EdgeKind_riscv::R_RISCV_ADD64; 470 case ELF::R_RISCV_SUB8: 471 return EdgeKind_riscv::R_RISCV_SUB8; 472 case ELF::R_RISCV_SUB16: 473 return EdgeKind_riscv::R_RISCV_SUB16; 474 case ELF::R_RISCV_SUB32: 475 return EdgeKind_riscv::R_RISCV_SUB32; 476 case ELF::R_RISCV_SUB64: 477 return EdgeKind_riscv::R_RISCV_SUB64; 478 case ELF::R_RISCV_SUB6: 479 return EdgeKind_riscv::R_RISCV_SUB6; 480 case ELF::R_RISCV_SET6: 481 return EdgeKind_riscv::R_RISCV_SET6; 482 case ELF::R_RISCV_SET8: 483 return EdgeKind_riscv::R_RISCV_SET8; 484 case ELF::R_RISCV_SET16: 485 return EdgeKind_riscv::R_RISCV_SET16; 486 case ELF::R_RISCV_SET32: 487 return EdgeKind_riscv::R_RISCV_SET32; 488 case ELF::R_RISCV_32_PCREL: 489 return EdgeKind_riscv::R_RISCV_32_PCREL; 490 } 491 492 return make_error<JITLinkError>( 493 "Unsupported riscv relocation:" + formatv("{0:d}: ", Type) + 494 object::getELFRelocationTypeName(ELF::EM_RISCV, Type)); 495 } 496 497 Error addRelocations() override { 498 LLVM_DEBUG(dbgs() << "Processing relocations:\n"); 499 500 using Base = ELFLinkGraphBuilder<ELFT>; 501 using Self = ELFLinkGraphBuilder_riscv<ELFT>; 502 for (const auto &RelSect : Base::Sections) 503 if (Error Err = Base::forEachRelaRelocation(RelSect, this, 504 &Self::addSingleRelocation)) 505 return Err; 506 507 return Error::success(); 508 } 509 510 Error addSingleRelocation(const typename ELFT::Rela &Rel, 511 const typename ELFT::Shdr &FixupSect, 512 Block &BlockToFix) { 513 using Base = ELFLinkGraphBuilder<ELFT>; 514 515 uint32_t Type = Rel.getType(false); 516 // We do not implement linker relaxation, except what is required for 517 // alignment (see below). 518 if (Type == llvm::ELF::R_RISCV_RELAX) 519 return Error::success(); 520 521 int64_t Addend = Rel.r_addend; 522 if (Type == llvm::ELF::R_RISCV_ALIGN) { 523 uint64_t Alignment = PowerOf2Ceil(Addend); 524 // FIXME: Implement support for ensuring alignment together with linker 525 // relaxation; 2 bytes are guaranteed by the length of compressed 526 // instructions, so this does not need any action from our side. 527 if (Alignment > 2) 528 return make_error<JITLinkError>( 529 formatv("Unsupported relocation R_RISCV_ALIGN with alignment {0} " 530 "larger than 2 (addend: {1})", 531 Alignment, Addend)); 532 return Error::success(); 533 } 534 535 Expected<riscv::EdgeKind_riscv> Kind = getRelocationKind(Type); 536 if (!Kind) 537 return Kind.takeError(); 538 539 uint32_t SymbolIndex = Rel.getSymbol(false); 540 auto ObjSymbol = Base::Obj.getRelocationSymbol(Rel, Base::SymTabSec); 541 if (!ObjSymbol) 542 return ObjSymbol.takeError(); 543 544 Symbol *GraphSymbol = Base::getGraphSymbol(SymbolIndex); 545 if (!GraphSymbol) 546 return make_error<StringError>( 547 formatv("Could not find symbol at given index, did you add it to " 548 "JITSymbolTable? index: {0}, shndx: {1} Size of table: {2}", 549 SymbolIndex, (*ObjSymbol)->st_shndx, 550 Base::GraphSymbols.size()), 551 inconvertibleErrorCode()); 552 553 auto FixupAddress = orc::ExecutorAddr(FixupSect.sh_addr) + Rel.r_offset; 554 Edge::OffsetT Offset = FixupAddress - BlockToFix.getAddress(); 555 Edge GE(*Kind, Offset, *GraphSymbol, Addend); 556 LLVM_DEBUG({ 557 dbgs() << " "; 558 printEdge(dbgs(), BlockToFix, GE, riscv::getEdgeKindName(*Kind)); 559 dbgs() << "\n"; 560 }); 561 562 BlockToFix.addEdge(std::move(GE)); 563 return Error::success(); 564 } 565 566 public: 567 ELFLinkGraphBuilder_riscv(StringRef FileName, 568 const object::ELFFile<ELFT> &Obj, const Triple T) 569 : ELFLinkGraphBuilder<ELFT>(Obj, std::move(T), FileName, 570 riscv::getEdgeKindName) {} 571 }; 572 573 Expected<std::unique_ptr<LinkGraph>> 574 createLinkGraphFromELFObject_riscv(MemoryBufferRef ObjectBuffer) { 575 LLVM_DEBUG({ 576 dbgs() << "Building jitlink graph for new input " 577 << ObjectBuffer.getBufferIdentifier() << "...\n"; 578 }); 579 580 auto ELFObj = object::ObjectFile::createELFObjectFile(ObjectBuffer); 581 if (!ELFObj) 582 return ELFObj.takeError(); 583 584 if ((*ELFObj)->getArch() == Triple::riscv64) { 585 auto &ELFObjFile = cast<object::ELFObjectFile<object::ELF64LE>>(**ELFObj); 586 return ELFLinkGraphBuilder_riscv<object::ELF64LE>( 587 (*ELFObj)->getFileName(), ELFObjFile.getELFFile(), 588 (*ELFObj)->makeTriple()) 589 .buildGraph(); 590 } else { 591 assert((*ELFObj)->getArch() == Triple::riscv32 && 592 "Invalid triple for RISCV ELF object file"); 593 auto &ELFObjFile = cast<object::ELFObjectFile<object::ELF32LE>>(**ELFObj); 594 return ELFLinkGraphBuilder_riscv<object::ELF32LE>( 595 (*ELFObj)->getFileName(), ELFObjFile.getELFFile(), 596 (*ELFObj)->makeTriple()) 597 .buildGraph(); 598 } 599 } 600 601 void link_ELF_riscv(std::unique_ptr<LinkGraph> G, 602 std::unique_ptr<JITLinkContext> Ctx) { 603 PassConfiguration Config; 604 const Triple &TT = G->getTargetTriple(); 605 if (Ctx->shouldAddDefaultTargetPasses(TT)) { 606 if (auto MarkLive = Ctx->getMarkLivePass(TT)) 607 Config.PrePrunePasses.push_back(std::move(MarkLive)); 608 else 609 Config.PrePrunePasses.push_back(markAllSymbolsLive); 610 Config.PostPrunePasses.push_back( 611 PerGraphGOTAndPLTStubsBuilder_ELF_riscv::asPass); 612 } 613 if (auto Err = Ctx->modifyPassConfig(*G, Config)) 614 return Ctx->notifyFailed(std::move(Err)); 615 616 ELFJITLinker_riscv::link(std::move(Ctx), std::move(G), std::move(Config)); 617 } 618 619 } // namespace jitlink 620 } // namespace llvm 621