diff options
Diffstat (limited to 'lld/ELF/Arch/PPC.cpp')
| -rw-r--r-- | lld/ELF/Arch/PPC.cpp | 186 |
1 files changed, 185 insertions, 1 deletions
diff --git a/lld/ELF/Arch/PPC.cpp b/lld/ELF/Arch/PPC.cpp index ee15575bfd5..8f68d12abe8 100644 --- a/lld/ELF/Arch/PPC.cpp +++ b/lld/ELF/Arch/PPC.cpp @@ -39,12 +39,27 @@ public: RelExpr getRelExpr(RelType Type, const Symbol &S, const uint8_t *Loc) const override; void relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const override; + RelExpr adjustRelaxExpr(RelType Type, const uint8_t *Data, + RelExpr Expr) const override; + int getTlsGdRelaxSkip(RelType Type) const override; + void relaxTlsGdToIe(uint8_t *Loc, RelType Type, uint64_t Val) const override; + void relaxTlsGdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const override; + void relaxTlsLdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const override; + void relaxTlsIeToLe(uint8_t *Loc, RelType Type, uint64_t Val) const override; }; } // namespace static uint16_t lo(uint32_t V) { return V; } static uint16_t ha(uint32_t V) { return (V + 0x8000) >> 16; } +static uint32_t readFromHalf16(const uint8_t *Loc) { + return read32(Loc - (Config->EKind == ELF32BEKind ? 2 : 0)); +} + +static void writeFromHalf16(uint8_t *Loc, uint32_t Insn) { + write32(Loc - (Config->EKind == ELF32BEKind ? 2 : 0), Insn); +} + void elf::writePPC32GlinkSection(uint8_t *Buf, size_t NumEntries) { // On PPC Secure PLT ABI, bl foo@plt jumps to a call stub, which loads an // absolute address from a specific .plt slot (usually called .got.plt on @@ -128,6 +143,10 @@ PPC::PPC() { NeedsThunks = true; + TlsModuleIndexRel = R_PPC_DTPMOD32; + TlsOffsetRel = R_PPC_DTPREL32; + TlsGotRel = R_PPC_TPREL32; + DefaultMaxPageSize = 65536; DefaultImageBase = 0x10000000; @@ -169,6 +188,12 @@ bool PPC::inBranchRange(RelType Type, uint64_t Src, uint64_t Dst) const { RelExpr PPC::getRelExpr(RelType Type, const Symbol &S, const uint8_t *Loc) const { switch (Type) { + case R_PPC_DTPREL16: + case R_PPC_DTPREL16_HA: + case R_PPC_DTPREL16_HI: + case R_PPC_DTPREL16_LO: + case R_PPC_DTPREL32: + return R_DTPREL; case R_PPC_REL14: case R_PPC_REL32: case R_PPC_LOCAL24PC: @@ -182,28 +207,84 @@ RelExpr PPC::getRelExpr(RelType Type, const Symbol &S, return R_PLT_PC; case R_PPC_PLTREL24: return R_PPC32_PLTREL; + case R_PPC_GOT_TLSGD16: + return R_TLSGD_GOT; + case R_PPC_GOT_TLSLD16: + return R_TLSLD_GOT; + case R_PPC_GOT_TPREL16: + return R_GOT_OFF; + case R_PPC_TLS: + return R_TLSIE_HINT; + case R_PPC_TLSGD: + return R_TLSDESC_CALL; + case R_PPC_TLSLD: + return R_TLSLD_HINT; + case R_PPC_TPREL16: + case R_PPC_TPREL16_HA: + case R_PPC_TPREL16_LO: + case R_PPC_TPREL16_HI: + return R_TLS; default: return R_ABS; } } -void PPC::relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const { +static std::pair<RelType, uint64_t> fromDTPREL(RelType Type, uint64_t Val) { + uint64_t DTPBiasedVal = Val - 0x8000; switch (Type) { + case R_PPC_DTPREL16: + return {R_PPC64_ADDR16, DTPBiasedVal}; + case R_PPC_DTPREL16_HA: + return {R_PPC_ADDR16_HA, DTPBiasedVal}; + case R_PPC_DTPREL16_HI: + return {R_PPC_ADDR16_HI, DTPBiasedVal}; + case R_PPC_DTPREL16_LO: + return {R_PPC_ADDR16_LO, DTPBiasedVal}; + case R_PPC_DTPREL32: + return {R_PPC_ADDR32, DTPBiasedVal}; + default: + return {Type, Val}; + } +} + +void PPC::relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const { + RelType NewType; + std::tie(NewType, Val) = fromDTPREL(Type, Val); + switch (NewType) { case R_PPC_ADDR16: case R_PPC_GOT16: + case R_PPC_GOT_TLSGD16: + case R_PPC_GOT_TLSLD16: + case R_PPC_GOT_TPREL16: + case R_PPC_TPREL16: checkInt(Loc, Val, 16, Type); write16(Loc, Val); break; case R_PPC_ADDR16_HA: + case R_PPC_DTPREL16_HA: + case R_PPC_GOT_TLSGD16_HA: + case R_PPC_GOT_TLSLD16_HA: + case R_PPC_GOT_TPREL16_HA: case R_PPC_REL16_HA: + case R_PPC_TPREL16_HA: write16(Loc, ha(Val)); break; case R_PPC_ADDR16_HI: + case R_PPC_DTPREL16_HI: + case R_PPC_GOT_TLSGD16_HI: + case R_PPC_GOT_TLSLD16_HI: + case R_PPC_GOT_TPREL16_HI: case R_PPC_REL16_HI: + case R_PPC_TPREL16_HI: write16(Loc, Val >> 16); break; case R_PPC_ADDR16_LO: + case R_PPC_DTPREL16_LO: + case R_PPC_GOT_TLSGD16_LO: + case R_PPC_GOT_TLSLD16_LO: + case R_PPC_GOT_TPREL16_LO: case R_PPC_REL16_LO: + case R_PPC_TPREL16_LO: write16(Loc, Val); break; case R_PPC_ADDR32: @@ -232,6 +313,109 @@ void PPC::relocateOne(uint8_t *Loc, RelType Type, uint64_t Val) const { } } +RelExpr PPC::adjustRelaxExpr(RelType Type, const uint8_t *Data, + RelExpr Expr) const { + if (Expr == R_RELAX_TLS_GD_TO_IE) + return R_RELAX_TLS_GD_TO_IE_GOT_OFF; + if (Expr == R_RELAX_TLS_LD_TO_LE) + return R_RELAX_TLS_LD_TO_LE_ABS; + return Expr; +} + +int PPC::getTlsGdRelaxSkip(RelType Type) const { + // A __tls_get_addr call instruction is marked with 2 relocations: + // + // R_PPC_TLSGD / R_PPC_TLSLD: marker relocation + // R_PPC_REL24: __tls_get_addr + // + // After the relaxation we no longer call __tls_get_addr and should skip both + // relocations to not create a false dependence on __tls_get_addr being + // defined. + if (Type == R_PPC_TLSGD || Type == R_PPC_TLSLD) + return 2; + return 1; +} + +void PPC::relaxTlsGdToIe(uint8_t *Loc, RelType Type, uint64_t Val) const { + switch (Type) { + case R_PPC_GOT_TLSGD16: { + // addi rT, rA, x@got@tlsgd --> lwz rT, x@got@tprel(rA) + uint32_t Insn = readFromHalf16(Loc); + writeFromHalf16(Loc, 0x80000000 | (Insn & 0x03ff0000)); + relocateOne(Loc, R_PPC_GOT_TPREL16, Val); + break; + } + case R_PPC_TLSGD: + // bl __tls_get_addr(x@tldgd) --> add r3, r3, r2 + write32(Loc, 0x7c631214); + break; + default: + llvm_unreachable("unsupported relocation for TLS GD to IE relaxation"); + } +} + +void PPC::relaxTlsGdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const { + switch (Type) { + case R_PPC_GOT_TLSGD16: + // addi r3, r31, x@got@tlsgd --> addis r3, r2, x@tprel@ha + writeFromHalf16(Loc, 0x3c620000 | ha(Val)); + break; + case R_PPC_TLSGD: + // bl __tls_get_addr(x@tldgd) --> add r3, r3, x@tprel@l + write32(Loc, 0x38630000 | lo(Val)); + break; + default: + llvm_unreachable("unsupported relocation for TLS GD to LE relaxation"); + } +} + +void PPC::relaxTlsLdToLe(uint8_t *Loc, RelType Type, uint64_t Val) const { + switch (Type) { + case R_PPC_GOT_TLSLD16: + // addi r3, rA, x@got@tlsgd --> addis r3, r2, 0 + writeFromHalf16(Loc, 0x3c620000); + break; + case R_PPC_TLSLD: + // r3+x@dtprel computes r3+x-0x8000, while we want it to compute r3+x@tprel + // = r3+x-0x7000, so add 4096 to r3. + // bl __tls_get_addr(x@tlsld) --> addi r3, r3, 4096 + write32(Loc, 0x38631000); + break; + case R_PPC_DTPREL16: + case R_PPC_DTPREL16_HA: + case R_PPC_DTPREL16_HI: + case R_PPC_DTPREL16_LO: + relocateOne(Loc, Type, Val); + break; + default: + llvm_unreachable("unsupported relocation for TLS LD to LE relaxation"); + } +} + +void PPC::relaxTlsIeToLe(uint8_t *Loc, RelType Type, uint64_t Val) const { + switch (Type) { + case R_PPC_GOT_TPREL16: { + // lwz rT, x@got@tprel(rA) --> addis rT, r2, x@tprel@ha + uint32_t RT = readFromHalf16(Loc) & 0x03e00000; + writeFromHalf16(Loc, 0x3c020000 | RT | ha(Val)); + break; + } + case R_PPC_TLS: { + uint32_t Insn = read32(Loc); + if (Insn >> 26 != 31) + error("unrecognized instruction for IE to LE R_PPC_TLS"); + // addi rT, rT, x@tls --> addi rT, rT, x@tprel@l + uint32_t DFormOp = getPPCDFormOp((read32(Loc) & 0x000007fe) >> 1); + if (DFormOp == 0) + error("unrecognized instruction for IE to LE R_PPC_TLS"); + write32(Loc, (DFormOp << 26) | (Insn & 0x03ff0000) | lo(Val)); + break; + } + default: + llvm_unreachable("unsupported relocation for TLS IE to LE relaxation"); + } +} + TargetInfo *elf::getPPCTargetInfo() { static PPC Target; return &Target; |
