lld/ELF/Arch/PPC.cpp

   1 //===- PPC.cpp ------------------------------------------------------------===//
   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 #include "OutputSections.h"
  10 #include "Symbols.h"
  11 #include "SyntheticSections.h"
  12 #include "Target.h"
  13 #include "Thunks.h"
  14 #include "lld/Common/ErrorHandler.h"
  15 #include "llvm/Support/Endian.h"
  16
  17 using namespace llvm;
  18 using namespace llvm::support::endian;
  19 using namespace llvm::ELF;
  20 using namespace lld;
  21 using namespace lld::elf;
  22
  23 // Undefine the macro predefined by GCC powerpc32.
  24 #undef PPC
  25
  26 namespace {
  27 class PPC final : public TargetInfo {
  28 public:
  29   PPC();
  30   RelExpr getRelExpr(RelType type, const Symbol &s,
  31                      const uint8_t *loc) const override;
  32   RelType getDynRel(RelType type) const override;
  33   int64_t getImplicitAddend(const uint8_t *buf, RelType type) const override;
  34   void writeGotHeader(uint8_t *buf) const override;
  35   void writePltHeader(uint8_t *buf) const override {
  36     llvm_unreachable("should call writePPC32GlinkSection() instead");
  37   }
  38   void writePlt(uint8_t *buf, const Symbol &sym,
  39                 uint64_t pltEntryAddr) const override {
  40     llvm_unreachable("should call writePPC32GlinkSection() instead");
  41   }
  42   void writeIplt(uint8_t *buf, const Symbol &sym,
  43                  uint64_t pltEntryAddr) const override;
  44   void writeGotPlt(uint8_t *buf, const Symbol &s) const override;
  45   bool needsThunk(RelExpr expr, RelType relocType, const InputFile *file,
  46                   uint64_t branchAddr, const Symbol &s,
  47                   int64_t a) const override;
  48   uint32_t getThunkSectionSpacing() const override;
  49   bool inBranchRange(RelType type, uint64_t src, uint64_t dst) const override;
  50   void relocate(uint8_t *loc, const Relocation &rel,
  51                 uint64_t val) const override;
  52   RelExpr adjustTlsExpr(RelType type, RelExpr expr) const override;
  53   int getTlsGdRelaxSkip(RelType type) const override;
  54   void relocateAlloc(InputSectionBase &sec, uint8_t *buf) const override;
  55
  56 private:
  57   void relaxTlsGdToIe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
  58   void relaxTlsGdToLe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
  59   void relaxTlsLdToLe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
  60   void relaxTlsIeToLe(uint8_t *loc, const Relocation &rel, uint64_t val) const;
  61 };
  62 } // namespace
  63
  64 static uint16_t lo(uint32_t v) { return v; }
  65 static uint16_t ha(uint32_t v) { return (v + 0x8000) >> 16; }
  66
  67 static uint32_t readFromHalf16(const uint8_t *loc) {
  68   return read32(config->isLE ? loc : loc - 2);
  69 }
  70
  71 static void writeFromHalf16(uint8_t *loc, uint32_t insn) {
  72   write32(config->isLE ? loc : loc - 2, insn);
  73 }
  74
  75 void elf::writePPC32GlinkSection(uint8_t *buf, size_t numEntries) {
  76   // Create canonical PLT entries for non-PIE code. Compilers don't generate
  77   // non-GOT-non-PLT relocations referencing external functions for -fpie/-fPIE.
  78   uint32_t glink = in.plt->getVA(); // VA of .glink
  79   if (!config->isPic) {
  80     for (const Symbol *sym : cast<PPC32GlinkSection>(*in.plt).canonical_plts) {
  81       writePPC32PltCallStub(buf, sym->getGotPltVA(), nullptr, 0);
  82       buf += 16;
  83       glink += 16;
  84     }
  85   }
  86
  87   // On PPC Secure PLT ABI, bl foo@plt jumps to a call stub, which loads an
  88   // absolute address from a specific .plt slot (usually called .got.plt on
  89   // other targets) and jumps there.
  90   //
  91   // a) With immediate binding (BIND_NOW), the .plt entry is resolved at load
  92   // time. The .glink section is not used.
  93   // b) With lazy binding, the .plt entry points to a `b PLTresolve`
  94   // instruction in .glink, filled in by PPC::writeGotPlt().
  95
  96   // Write N `b PLTresolve` first.
  97   for (size_t i = 0; i != numEntries; ++i)
  98     write32(buf + 4 * i, 0x48000000 | 4 * (numEntries - i));
  99   buf += 4 * numEntries;
 100
 101   // Then write PLTresolve(), which has two forms: PIC and non-PIC. PLTresolve()
 102   // computes the PLT index (by computing the distance from the landing b to
 103   // itself) and calls _dl_runtime_resolve() (in glibc).
 104   uint32_t got = in.got->getVA();
 105   const uint8_t *end = buf + 64;
 106   if (config->isPic) {
 107     uint32_t afterBcl = 4 * in.plt->getNumEntries() + 12;
 108     uint32_t gotBcl = got + 4 - (glink + afterBcl);
 109     write32(buf + 0, 0x3d6b0000 | ha(afterBcl));  // addis r11,r11,1f-glink@ha
 110     write32(buf + 4, 0x7c0802a6);                 // mflr r0
 111     write32(buf + 8, 0x429f0005);                 // bcl 20,30,.+4
 112     write32(buf + 12, 0x396b0000 | lo(afterBcl)); // 1: addi r11,r11,1b-glink@l
 113     write32(buf + 16, 0x7d8802a6);                // mflr r12
 114     write32(buf + 20, 0x7c0803a6);                // mtlr r0
 115     write32(buf + 24, 0x7d6c5850);                // sub r11,r11,r12
 116     write32(buf + 28, 0x3d8c0000 | ha(gotBcl));   // addis 12,12,GOT+4-1b@ha
 117     if (ha(gotBcl) == ha(gotBcl + 4)) {
 118       write32(buf + 32, 0x800c0000 | lo(gotBcl)); // lwz r0,r12,GOT+4-1b@l(r12)
 119       write32(buf + 36,
 120               0x818c0000 | lo(gotBcl + 4));       // lwz r12,r12,GOT+8-1b@l(r12)
 121     } else {
 122       write32(buf + 32, 0x840c0000 | lo(gotBcl)); // lwzu r0,r12,GOT+4-1b@l(r12)
 123       write32(buf + 36, 0x818c0000 | 4);          // lwz r12,r12,4(r12)
 124     }
 125     write32(buf + 40, 0x7c0903a6);                // mtctr 0
 126     write32(buf + 44, 0x7c0b5a14);                // add r0,11,11
 127     write32(buf + 48, 0x7d605a14);                // add r11,0,11
 128     write32(buf + 52, 0x4e800420);                // bctr
 129     buf += 56;
 130   } else {
 131     write32(buf + 0, 0x3d800000 | ha(got + 4));   // lis     r12,GOT+4@ha
 132     write32(buf + 4, 0x3d6b0000 | ha(-glink));    // addis   r11,r11,-glink@ha
 133     if (ha(got + 4) == ha(got + 8))
 134       write32(buf + 8, 0x800c0000 | lo(got + 4)); // lwz r0,GOT+4@l(r12)
 135     else
 136       write32(buf + 8, 0x840c0000 | lo(got + 4)); // lwzu r0,GOT+4@l(r12)
 137     write32(buf + 12, 0x396b0000 | lo(-glink));   // addi    r11,r11,-glink@l
 138     write32(buf + 16, 0x7c0903a6);                // mtctr   r0
 139     write32(buf + 20, 0x7c0b5a14);                // add     r0,r11,r11
 140     if (ha(got + 4) == ha(got + 8))
 141       write32(buf + 24, 0x818c0000 | lo(got + 8)); // lwz r12,GOT+8@l(r12)
 142     else
 143       write32(buf + 24, 0x818c0000 | 4);          // lwz r12,4(r12)
 144     write32(buf + 28, 0x7d605a14);                // add     r11,r0,r11
 145     write32(buf + 32, 0x4e800420);                // bctr
 146     buf += 36;
 147   }
 148
 149   // Pad with nop. They should not be executed.
 150   for (; buf < end; buf += 4)
 151     write32(buf, 0x60000000);
 152 }
 153
 154 PPC::PPC() {
 155   copyRel = R_PPC_COPY;
 156   gotRel = R_PPC_GLOB_DAT;
 157   pltRel = R_PPC_JMP_SLOT;
 158   relativeRel = R_PPC_RELATIVE;
 159   iRelativeRel = R_PPC_IRELATIVE;
 160   symbolicRel = R_PPC_ADDR32;
 161   gotHeaderEntriesNum = 3;
 162   gotPltHeaderEntriesNum = 0;
 163   pltHeaderSize = 0;
 164   pltEntrySize = 4;
 165   ipltEntrySize = 16;
 166
 167   needsThunks = true;
 168
 169   tlsModuleIndexRel = R_PPC_DTPMOD32;
 170   tlsOffsetRel = R_PPC_DTPREL32;
 171   tlsGotRel = R_PPC_TPREL32;
 172
 173   defaultMaxPageSize = 65536;
 174   defaultImageBase = 0x10000000;
 175
 176   write32(trapInstr.data(), 0x7fe00008);
 177 }
 178
 179 void PPC::writeIplt(uint8_t *buf, const Symbol &sym,
 180                     uint64_t /*pltEntryAddr*/) const {
 181   // In -pie or -shared mode, assume r30 points to .got2+0x8000, and use a
 182   // .got2.plt_pic32. thunk.
 183   writePPC32PltCallStub(buf, sym.getGotPltVA(), sym.file, 0x8000);
 184 }
 185
 186 void PPC::writeGotHeader(uint8_t *buf) const {
 187   // _GLOBAL_OFFSET_TABLE_[0] = _DYNAMIC
 188   // glibc stores _dl_runtime_resolve in _GLOBAL_OFFSET_TABLE_[1],
 189   // link_map in _GLOBAL_OFFSET_TABLE_[2].
 190   write32(buf, mainPart->dynamic->getVA());
 191 }
 192
 193 void PPC::writeGotPlt(uint8_t *buf, const Symbol &s) const {
 194   // Address of the symbol resolver stub in .glink .
 195   write32(buf, in.plt->getVA() + in.plt->headerSize + 4 * s.getPltIdx());
 196 }
 197
 198 bool PPC::needsThunk(RelExpr expr, RelType type, const InputFile *file,
 199                      uint64_t branchAddr, const Symbol &s, int64_t a) const {
 200   if (type != R_PPC_LOCAL24PC && type != R_PPC_REL24 && type != R_PPC_PLTREL24)
 201     return false;
 202   if (s.isInPlt())
 203     return true;
 204   if (s.isUndefWeak())
 205     return false;
 206   return !PPC::inBranchRange(type, branchAddr, s.getVA(a));
 207 }
 208
 209 uint32_t PPC::getThunkSectionSpacing() const { return 0x2000000; }
 210
 211 bool PPC::inBranchRange(RelType type, uint64_t src, uint64_t dst) const {
 212   uint64_t offset = dst - src;
 213   if (type == R_PPC_LOCAL24PC || type == R_PPC_REL24 || type == R_PPC_PLTREL24)
 214     return isInt<26>(offset);
 215   llvm_unreachable("unsupported relocation type used in branch");
 216 }
 217
 218 RelExpr PPC::getRelExpr(RelType type, const Symbol &s,
 219                         const uint8_t *loc) const {
 220   switch (type) {
 221   case R_PPC_NONE:
 222     return R_NONE;
 223   case R_PPC_ADDR16_HA:
 224   case R_PPC_ADDR16_HI:
 225   case R_PPC_ADDR16_LO:
 226   case R_PPC_ADDR24:
 227   case R_PPC_ADDR32:
 228     return R_ABS;
 229   case R_PPC_DTPREL16:
 230   case R_PPC_DTPREL16_HA:
 231   case R_PPC_DTPREL16_HI:
 232   case R_PPC_DTPREL16_LO:
 233   case R_PPC_DTPREL32:
 234     return R_DTPREL;
 235   case R_PPC_REL14:
 236   case R_PPC_REL32:
 237   case R_PPC_REL16_LO:
 238   case R_PPC_REL16_HI:
 239   case R_PPC_REL16_HA:
 240     return R_PC;
 241   case R_PPC_GOT16:
 242     return R_GOT_OFF;
 243   case R_PPC_LOCAL24PC:
 244   case R_PPC_REL24:
 245     return R_PLT_PC;
 246   case R_PPC_PLTREL24:
 247     return R_PPC32_PLTREL;
 248   case R_PPC_GOT_TLSGD16:
 249     return R_TLSGD_GOT;
 250   case R_PPC_GOT_TLSLD16:
 251     return R_TLSLD_GOT;
 252   case R_PPC_GOT_TPREL16:
 253     return R_GOT_OFF;
 254   case R_PPC_TLS:
 255     return R_TLSIE_HINT;
 256   case R_PPC_TLSGD:
 257     return R_TLSDESC_CALL;
 258   case R_PPC_TLSLD:
 259     return R_TLSLD_HINT;
 260   case R_PPC_TPREL16:
 261   case R_PPC_TPREL16_HA:
 262   case R_PPC_TPREL16_LO:
 263   case R_PPC_TPREL16_HI:
 264     return R_TPREL;
 265   default:
 266     error(getErrorLocation(loc) + "unknown relocation (" + Twine(type) +
 267           ") against symbol " + toString(s));
 268     return R_NONE;
 269   }
 270 }
 271
 272 RelType PPC::getDynRel(RelType type) const {
 273   if (type == R_PPC_ADDR32)
 274     return type;
 275   return R_PPC_NONE;
 276 }
 277
 278 int64_t PPC::getImplicitAddend(const uint8_t *buf, RelType type) const {
 279   switch (type) {
 280   case R_PPC_NONE:
 281   case R_PPC_GLOB_DAT:
 282   case R_PPC_JMP_SLOT:
 283     return 0;
 284   case R_PPC_ADDR32:
 285   case R_PPC_REL32:
 286   case R_PPC_RELATIVE:
 287   case R_PPC_IRELATIVE:
 288   case R_PPC_DTPMOD32:
 289   case R_PPC_DTPREL32:
 290   case R_PPC_TPREL32:
 291     return SignExtend64<32>(read32(buf));
 292   default:
 293     internalLinkerError(getErrorLocation(buf),
 294                         "cannot read addend for relocation " + toString(type));
 295     return 0;
 296   }
 297 }
 298
 299 static std::pair<RelType, uint64_t> fromDTPREL(RelType type, uint64_t val) {
 300   uint64_t dtpBiasedVal = val - 0x8000;
 301   switch (type) {
 302   case R_PPC_DTPREL16:
 303     return {R_PPC64_ADDR16, dtpBiasedVal};
 304   case R_PPC_DTPREL16_HA:
 305     return {R_PPC_ADDR16_HA, dtpBiasedVal};
 306   case R_PPC_DTPREL16_HI:
 307     return {R_PPC_ADDR16_HI, dtpBiasedVal};
 308   case R_PPC_DTPREL16_LO:
 309     return {R_PPC_ADDR16_LO, dtpBiasedVal};
 310   case R_PPC_DTPREL32:
 311     return {R_PPC_ADDR32, dtpBiasedVal};
 312   default:
 313     return {type, val};
 314   }
 315 }
 316
 317 void PPC::relocate(uint8_t *loc, const Relocation &rel, uint64_t val) const {
 318   RelType newType;
 319   std::tie(newType, val) = fromDTPREL(rel.type, val);
 320   switch (newType) {
 321   case R_PPC_ADDR16:
 322     checkIntUInt(loc, val, 16, rel);
 323     write16(loc, val);
 324     break;
 325   case R_PPC_GOT16:
 326   case R_PPC_GOT_TLSGD16:
 327   case R_PPC_GOT_TLSLD16:
 328   case R_PPC_GOT_TPREL16:
 329   case R_PPC_TPREL16:
 330     checkInt(loc, val, 16, rel);
 331     write16(loc, val);
 332     break;
 333   case R_PPC_ADDR16_HA:
 334   case R_PPC_DTPREL16_HA:
 335   case R_PPC_GOT_TLSGD16_HA:
 336   case R_PPC_GOT_TLSLD16_HA:
 337   case R_PPC_GOT_TPREL16_HA:
 338   case R_PPC_REL16_HA:
 339   case R_PPC_TPREL16_HA:
 340     write16(loc, ha(val));
 341     break;
 342   case R_PPC_ADDR16_HI:
 343   case R_PPC_DTPREL16_HI:
 344   case R_PPC_GOT_TLSGD16_HI:
 345   case R_PPC_GOT_TLSLD16_HI:
 346   case R_PPC_GOT_TPREL16_HI:
 347   case R_PPC_REL16_HI:
 348   case R_PPC_TPREL16_HI:
 349     write16(loc, val >> 16);
 350     break;
 351   case R_PPC_ADDR16_LO:
 352   case R_PPC_DTPREL16_LO:
 353   case R_PPC_GOT_TLSGD16_LO:
 354   case R_PPC_GOT_TLSLD16_LO:
 355   case R_PPC_GOT_TPREL16_LO:
 356   case R_PPC_REL16_LO:
 357   case R_PPC_TPREL16_LO:
 358     write16(loc, val);
 359     break;
 360   case R_PPC_ADDR32:
 361   case R_PPC_REL32:
 362     write32(loc, val);
 363     break;
 364   case R_PPC_REL14: {
 365     uint32_t mask = 0x0000FFFC;
 366     checkInt(loc, val, 16, rel);
 367     checkAlignment(loc, val, 4, rel);
 368     write32(loc, (read32(loc) & ~mask) | (val & mask));
 369     break;
 370   }
 371   case R_PPC_ADDR24:
 372   case R_PPC_REL24:
 373   case R_PPC_LOCAL24PC:
 374   case R_PPC_PLTREL24: {
 375     uint32_t mask = 0x03FFFFFC;
 376     checkInt(loc, val, 26, rel);
 377     checkAlignment(loc, val, 4, rel);
 378     write32(loc, (read32(loc) & ~mask) | (val & mask));
 379     break;
 380   }
 381   default:
 382     llvm_unreachable("unknown relocation");
 383   }
 384 }
 385
 386 RelExpr PPC::adjustTlsExpr(RelType type, RelExpr expr) const {
 387   if (expr == R_RELAX_TLS_GD_TO_IE)
 388     return R_RELAX_TLS_GD_TO_IE_GOT_OFF;
 389   if (expr == R_RELAX_TLS_LD_TO_LE)
 390     return R_RELAX_TLS_LD_TO_LE_ABS;
 391   return expr;
 392 }
 393
 394 int PPC::getTlsGdRelaxSkip(RelType type) const {
 395   // A __tls_get_addr call instruction is marked with 2 relocations:
 396   //
 397   //   R_PPC_TLSGD / R_PPC_TLSLD: marker relocation
 398   //   R_PPC_REL24: __tls_get_addr
 399   //
 400   // After the relaxation we no longer call __tls_get_addr and should skip both
 401   // relocations to not create a false dependence on __tls_get_addr being
 402   // defined.
 403   if (type == R_PPC_TLSGD || type == R_PPC_TLSLD)
 404     return 2;
 405   return 1;
 406 }
 407
 408 void PPC::relaxTlsGdToIe(uint8_t *loc, const Relocation &rel,
 409                          uint64_t val) const {
 410   switch (rel.type) {
 411   case R_PPC_GOT_TLSGD16: {
 412     // addi rT, rA, x@got@tlsgd --> lwz rT, x@got@tprel(rA)
 413     uint32_t insn = readFromHalf16(loc);
 414     writeFromHalf16(loc, 0x80000000 | (insn & 0x03ff0000));
 415     relocateNoSym(loc, R_PPC_GOT_TPREL16, val);
 416     break;
 417   }
 418   case R_PPC_TLSGD:
 419     // bl __tls_get_addr(x@tldgd) --> add r3, r3, r2
 420     write32(loc, 0x7c631214);
 421     break;
 422   default:
 423     llvm_unreachable("unsupported relocation for TLS GD to IE relaxation");
 424   }
 425 }
 426
 427 void PPC::relaxTlsGdToLe(uint8_t *loc, const Relocation &rel,
 428                          uint64_t val) const {
 429   switch (rel.type) {
 430   case R_PPC_GOT_TLSGD16:
 431     // addi r3, r31, x@got@tlsgd --> addis r3, r2, x@tprel@ha
 432     writeFromHalf16(loc, 0x3c620000 | ha(val));
 433     break;
 434   case R_PPC_TLSGD:
 435     // bl __tls_get_addr(x@tldgd) --> add r3, r3, x@tprel@l
 436     write32(loc, 0x38630000 | lo(val));
 437     break;
 438   default:
 439     llvm_unreachable("unsupported relocation for TLS GD to LE relaxation");
 440   }
 441 }
 442
 443 void PPC::relaxTlsLdToLe(uint8_t *loc, const Relocation &rel,
 444                          uint64_t val) const {
 445   switch (rel.type) {
 446   case R_PPC_GOT_TLSLD16:
 447     // addi r3, rA, x@got@tlsgd --> addis r3, r2, 0
 448     writeFromHalf16(loc, 0x3c620000);
 449     break;
 450   case R_PPC_TLSLD:
 451     // r3+x@dtprel computes r3+x-0x8000, while we want it to compute r3+x@tprel
 452     // = r3+x-0x7000, so add 4096 to r3.
 453     // bl __tls_get_addr(x@tlsld) --> addi r3, r3, 4096
 454     write32(loc, 0x38631000);
 455     break;
 456   case R_PPC_DTPREL16:
 457   case R_PPC_DTPREL16_HA:
 458   case R_PPC_DTPREL16_HI:
 459   case R_PPC_DTPREL16_LO:
 460     relocate(loc, rel, val);
 461     break;
 462   default:
 463     llvm_unreachable("unsupported relocation for TLS LD to LE relaxation");
 464   }
 465 }
 466
 467 void PPC::relaxTlsIeToLe(uint8_t *loc, const Relocation &rel,
 468                          uint64_t val) const {
 469   switch (rel.type) {
 470   case R_PPC_GOT_TPREL16: {
 471     // lwz rT, x@got@tprel(rA) --> addis rT, r2, x@tprel@ha
 472     uint32_t rt = readFromHalf16(loc) & 0x03e00000;
 473     writeFromHalf16(loc, 0x3c020000 | rt | ha(val));
 474     break;
 475   }
 476   case R_PPC_TLS: {
 477     uint32_t insn = read32(loc);
 478     if (insn >> 26 != 31)
 479       error("unrecognized instruction for IE to LE R_PPC_TLS");
 480     // addi rT, rT, x@tls --> addi rT, rT, x@tprel@l
 481     unsigned secondaryOp = (read32(loc) & 0x000007fe) >> 1;
 482     uint32_t dFormOp = getPPCDFormOp(secondaryOp);
 483     if (dFormOp == 0) { // Expecting a DS-Form instruction.
 484       dFormOp = getPPCDSFormOp(secondaryOp);
 485       if (dFormOp == 0)
 486         error("unrecognized instruction for IE to LE R_PPC_TLS");
 487     }
 488     write32(loc, (dFormOp | (insn & 0x03ff0000) | lo(val)));
 489     break;
 490   }
 491   default:
 492     llvm_unreachable("unsupported relocation for TLS IE to LE relaxation");
 493   }
 494 }
 495
 496 void PPC::relocateAlloc(InputSectionBase &sec, uint8_t *buf) const {
 497   uint64_t secAddr = sec.getOutputSection()->addr;
 498   if (auto *s = dyn_cast<InputSection>(&sec))
 499     secAddr += s->outSecOff;
 500   for (const Relocation &rel : sec.relocs()) {
 501     uint8_t *loc = buf + rel.offset;
 502     const uint64_t val = SignExtend64(
 503         sec.getRelocTargetVA(sec.file, rel.type, rel.addend,
 504                              secAddr + rel.offset, *rel.sym, rel.expr),
 505         32);
 506     switch (rel.expr) {
 507     case R_RELAX_TLS_GD_TO_IE_GOT_OFF:
 508       relaxTlsGdToIe(loc, rel, val);
 509       break;
 510     case R_RELAX_TLS_GD_TO_LE:
 511       relaxTlsGdToLe(loc, rel, val);
 512       break;
 513     case R_RELAX_TLS_LD_TO_LE_ABS:
 514       relaxTlsLdToLe(loc, rel, val);
 515       break;
 516     case R_RELAX_TLS_IE_TO_LE:
 517       relaxTlsIeToLe(loc, rel, val);
 518       break;
 519     default:
 520       relocate(loc, rel, val);
 521       break;
 522     }
 523   }
 524 }
 525
 526 TargetInfo *elf::getPPCTargetInfo() {
 527   static PPC target;
 528   return &target;
 529 }