// If linker relaxation is enabled, or the relax option had previously been
// enabled, always emit relocations even if the fixup can be resolved. This is
// necessary for correctness as offsets may change during relaxation.
bool RISCVAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
const MCFixup &Fixup,
const MCValue &Target) {
bool ShouldForce = false;
switch ((unsigned)Fixup.getKind()) {
default:
break;
case RISCV::fixup_riscv_pcrel_lo12_i:
case RISCV::fixup_riscv_pcrel_lo12_s:
// For pcrel_lo12, force a relocation if the target of the corresponding
// pcrel_hi20 is not in the same fragment.
const MCFixup *T = cast<RISCVMCExpr>(Fixup.getValue())->getPCRelHiFixup();
if (!T) {
Asm.getContext().reportError(Fixup.getLoc(),
"could not find corresponding %pcrel_hi");
return false;
}
switch ((unsigned)T->getKind()) {
default:
llvm_unreachable("Unexpected fixup kind for pcrel_lo12");
break;
case RISCV::fixup_riscv_pcrel_hi20:
ShouldForce = T->getValue()->findAssociatedFragment() !=
Fixup.getValue()->findAssociatedFragment();
break;
}
break;
}
return ShouldForce || STI.getFeatureBits()[RISCV::FeatureRelax] ||
ForceRelocs;
}
unsigned X86ELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
MCSymbolRefExpr::VariantKind Modifier = Target.getAccessVariant();
X86_64RelType Type = getType64(Fixup.getKind(), Modifier, IsPCRel);
if (getEMachine() == ELF::EM_X86_64)
return getRelocType64(Ctx, Fixup.getLoc(), Modifier, Type, IsPCRel,
Fixup.getKind());
assert((getEMachine() == ELF::EM_386 || getEMachine() == ELF::EM_IAMCU) &&
"Unsupported ELF machine type.");
return getRelocType32(Modifier, getType32(Type), IsPCRel);
}
static uint64_t adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
MCContext *Ctx) {
int64_t SignedValue = static_cast<int64_t>(Value);
switch (Fixup.getKind()) {
case AMDGPU::fixup_si_sopp_br: {
int64_t BrImm = (SignedValue - 4) / 4;
if (Ctx && !isInt<16>(BrImm))
Ctx->reportError(Fixup.getLoc(), "branch size exceeds simm16");
return BrImm;
}
case FK_Data_1:
case FK_Data_2:
case FK_Data_4:
case FK_Data_8:
case FK_PCRel_4:
case FK_SecRel_4:
return Value;
default:
llvm_unreachable("unhandled fixup kind");
}
}
unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
AArch64MCExpr::VariantKind RefKind =
static_cast<AArch64MCExpr::VariantKind>(Target.getRefKind());
AArch64MCExpr::VariantKind SymLoc = AArch64MCExpr::getSymbolLoc(RefKind);
bool IsNC = AArch64MCExpr::isNotChecked(RefKind);
assert((!Target.getSymA() ||
Target.getSymA()->getKind() == MCSymbolRefExpr::VK_None) &&
"Should only be expression-level modifiers here");
assert((!Target.getSymB() ||
Target.getSymB()->getKind() == MCSymbolRefExpr::VK_None) &&
"Should only be expression-level modifiers here");
if (IsPCRel) {
switch ((unsigned)Fixup.getKind()) {
case FK_Data_1:
Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
return ELF::R_AARCH64_NONE;
case FK_Data_2:
return R_CLS(PREL16);
case FK_Data_4:
return R_CLS(PREL32);
case FK_Data_8:
if (IsILP32) {
Ctx.reportError(Fixup.getLoc(), "ILP32 8 byte PC relative data "
"relocation not supported (LP64 eqv: PREL64)");
return ELF::R_AARCH64_NONE;
} else
return ELF::R_AARCH64_PREL64;
case AArch64::fixup_aarch64_pcrel_adr_imm21:
assert(SymLoc == AArch64MCExpr::VK_NONE && "unexpected ADR relocation");
return R_CLS(ADR_PREL_LO21);
case AArch64::fixup_aarch64_pcrel_adrp_imm21:
if (SymLoc == AArch64MCExpr::VK_ABS && !IsNC)
return R_CLS(ADR_PREL_PG_HI21);
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC) {
if (IsILP32) {
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 32-bit pcrel ADRP instruction "
"VK_ABS VK_NC");
return ELF::R_AARCH64_NONE;
} else {
return ELF::R_AARCH64_ADR_PREL_PG_HI21_NC;
}
}
if (SymLoc == AArch64MCExpr::VK_GOT && !IsNC)
return R_CLS(ADR_GOT_PAGE);
if (SymLoc == AArch64MCExpr::VK_GOTTPREL && !IsNC)
return R_CLS(TLSIE_ADR_GOTTPREL_PAGE21);
if (SymLoc == AArch64MCExpr::VK_TLSDESC && !IsNC)
return R_CLS(TLSDESC_ADR_PAGE21);
Ctx.reportError(Fixup.getLoc(),
"invalid symbol kind for ADRP relocation");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_pcrel_branch26:
return R_CLS(JUMP26);
case AArch64::fixup_aarch64_pcrel_call26:
return R_CLS(CALL26);
case AArch64::fixup_aarch64_ldr_pcrel_imm19:
if (SymLoc == AArch64MCExpr::VK_GOTTPREL)
return R_CLS(TLSIE_LD_GOTTPREL_PREL19);
return R_CLS(LD_PREL_LO19);
case AArch64::fixup_aarch64_pcrel_branch14:
return R_CLS(TSTBR14);
case AArch64::fixup_aarch64_pcrel_branch19:
return R_CLS(CONDBR19);
default:
Ctx.reportError(Fixup.getLoc(), "Unsupported pc-relative fixup kind");
return ELF::R_AARCH64_NONE;
}
} else {
if (IsILP32 && isNonILP32reloc(Fixup, RefKind, Ctx))
return ELF::R_AARCH64_NONE;
switch ((unsigned)Fixup.getKind()) {
case FK_Data_1:
Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
return ELF::R_AARCH64_NONE;
case FK_Data_2:
return R_CLS(ABS16);
case FK_Data_4:
return R_CLS(ABS32);
case FK_Data_8:
if (IsILP32) {
Ctx.reportError(Fixup.getLoc(), "ILP32 8 byte absolute data "
"relocation not supported (LP64 eqv: ABS64)");
return ELF::R_AARCH64_NONE;
} else
return ELF::R_AARCH64_ABS64;
case AArch64::fixup_aarch64_add_imm12:
if (RefKind == AArch64MCExpr::VK_DTPREL_HI12)
return R_CLS(TLSLD_ADD_DTPREL_HI12);
if (RefKind == AArch64MCExpr::VK_TPREL_HI12)
return R_CLS(TLSLE_ADD_TPREL_HI12);
if (RefKind == AArch64MCExpr::VK_DTPREL_LO12_NC)
return R_CLS(TLSLD_ADD_DTPREL_LO12_NC);
if (RefKind == AArch64MCExpr::VK_DTPREL_LO12)
return R_CLS(TLSLD_ADD_DTPREL_LO12);
if (RefKind == AArch64MCExpr::VK_TPREL_LO12_NC)
return R_CLS(TLSLE_ADD_TPREL_LO12_NC);
if (RefKind == AArch64MCExpr::VK_TPREL_LO12)
return R_CLS(TLSLE_ADD_TPREL_LO12);
if (RefKind == AArch64MCExpr::VK_TLSDESC_LO12)
return R_CLS(TLSDESC_ADD_LO12);
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(ADD_ABS_LO12_NC);
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for add (uimm12) instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale1:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(LDST8_ABS_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return R_CLS(TLSLD_LDST8_DTPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return R_CLS(TLSLD_LDST8_DTPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return R_CLS(TLSLE_LDST8_TPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return R_CLS(TLSLE_LDST8_TPREL_LO12_NC);
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 8-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale2:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(LDST16_ABS_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return R_CLS(TLSLD_LDST16_DTPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return R_CLS(TLSLD_LDST16_DTPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return R_CLS(TLSLE_LDST16_TPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return R_CLS(TLSLE_LDST16_TPREL_LO12_NC);
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 16-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale4:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(LDST32_ABS_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return R_CLS(TLSLD_LDST32_DTPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return R_CLS(TLSLD_LDST32_DTPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return R_CLS(TLSLE_LDST32_TPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return R_CLS(TLSLE_LDST32_TPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_GOT && IsNC) {
if (IsILP32) {
return ELF::R_AARCH64_P32_LD32_GOT_LO12_NC;
} else {
Ctx.reportError(Fixup.getLoc(),
"LP64 4 byte unchecked GOT load/store relocation "
"not supported (ILP32 eqv: LD32_GOT_LO12_NC");
return ELF::R_AARCH64_NONE;
}
}
if (SymLoc == AArch64MCExpr::VK_GOT && !IsNC) {
if (IsILP32) {
Ctx.reportError(Fixup.getLoc(),
"ILP32 4 byte checked GOT load/store relocation "
"not supported (unchecked eqv: LD32_GOT_LO12_NC)");
} else {
Ctx.reportError(Fixup.getLoc(),
"LP64 4 byte checked GOT load/store relocation "
"not supported (unchecked/ILP32 eqv: "
"LD32_GOT_LO12_NC)");
}
return ELF::R_AARCH64_NONE;
}
if (SymLoc == AArch64MCExpr::VK_GOTTPREL && IsNC) {
if (IsILP32) {
return ELF::R_AARCH64_P32_TLSIE_LD32_GOTTPREL_LO12_NC;
} else {
Ctx.reportError(Fixup.getLoc(), "LP64 32-bit load/store "
"relocation not supported (ILP32 eqv: "
"TLSIE_LD32_GOTTPREL_LO12_NC)");
return ELF::R_AARCH64_NONE;
}
}
if (SymLoc == AArch64MCExpr::VK_TLSDESC && !IsNC) {
if (IsILP32) {
return ELF::R_AARCH64_P32_TLSDESC_LD32_LO12;
} else {
Ctx.reportError(Fixup.getLoc(),
"LP64 4 byte TLSDESC load/store relocation "
"not supported (ILP32 eqv: TLSDESC_LD64_LO12)");
return ELF::R_AARCH64_NONE;
}
}
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 32-bit load/store instruction "
"fixup_aarch64_ldst_imm12_scale4");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale8:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(LDST64_ABS_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_GOT && IsNC) {
if (!IsILP32) {
return ELF::R_AARCH64_LD64_GOT_LO12_NC;
} else {
Ctx.reportError(Fixup.getLoc(), "ILP32 64-bit load/store "
"relocation not supported (LP64 eqv: "
"LD64_GOT_LO12_NC)");
return ELF::R_AARCH64_NONE;
}
}
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return R_CLS(TLSLD_LDST64_DTPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return R_CLS(TLSLD_LDST64_DTPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return R_CLS(TLSLE_LDST64_TPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return R_CLS(TLSLE_LDST64_TPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_GOTTPREL && IsNC) {
if (!IsILP32) {
return ELF::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC;
} else {
Ctx.reportError(Fixup.getLoc(), "ILP32 64-bit load/store "
"relocation not supported (LP64 eqv: "
"TLSIE_LD64_GOTTPREL_LO12_NC)");
return ELF::R_AARCH64_NONE;
}
}
if (SymLoc == AArch64MCExpr::VK_TLSDESC) {
if (!IsILP32) {
return ELF::R_AARCH64_TLSDESC_LD64_LO12;
} else {
Ctx.reportError(Fixup.getLoc(), "ILP32 64-bit load/store "
"relocation not supported (LP64 eqv: "
"TLSDESC_LD64_LO12)");
return ELF::R_AARCH64_NONE;
}
}
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 64-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale16:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return R_CLS(LDST128_ABS_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return R_CLS(TLSLD_LDST128_DTPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return R_CLS(TLSLD_LDST128_DTPREL_LO12_NC);
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return R_CLS(TLSLE_LDST128_TPREL_LO12);
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return R_CLS(TLSLE_LDST128_TPREL_LO12_NC);
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 128-bit load/store instruction");
return ELF::R_AARCH64_NONE;
// ILP32 case not reached here, tested with isNonILP32reloc
case AArch64::fixup_aarch64_movw:
if (RefKind == AArch64MCExpr::VK_ABS_G3)
return ELF::R_AARCH64_MOVW_UABS_G3;
if (RefKind == AArch64MCExpr::VK_ABS_G2)
return ELF::R_AARCH64_MOVW_UABS_G2;
if (RefKind == AArch64MCExpr::VK_ABS_G2_S)
return ELF::R_AARCH64_MOVW_SABS_G2;
if (RefKind == AArch64MCExpr::VK_ABS_G2_NC)
return ELF::R_AARCH64_MOVW_UABS_G2_NC;
if (RefKind == AArch64MCExpr::VK_ABS_G1)
return R_CLS(MOVW_UABS_G1);
if (RefKind == AArch64MCExpr::VK_ABS_G1_S)
return ELF::R_AARCH64_MOVW_SABS_G1;
if (RefKind == AArch64MCExpr::VK_ABS_G1_NC)
return ELF::R_AARCH64_MOVW_UABS_G1_NC;
if (RefKind == AArch64MCExpr::VK_ABS_G0)
return R_CLS(MOVW_UABS_G0);
if (RefKind == AArch64MCExpr::VK_ABS_G0_S)
return R_CLS(MOVW_SABS_G0);
if (RefKind == AArch64MCExpr::VK_ABS_G0_NC)
return R_CLS(MOVW_UABS_G0_NC);
if (RefKind == AArch64MCExpr::VK_DTPREL_G2)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G2;
if (RefKind == AArch64MCExpr::VK_DTPREL_G1)
return R_CLS(TLSLD_MOVW_DTPREL_G1);
if (RefKind == AArch64MCExpr::VK_DTPREL_G1_NC)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G1_NC;
if (RefKind == AArch64MCExpr::VK_DTPREL_G0)
return R_CLS(TLSLD_MOVW_DTPREL_G0);
if (RefKind == AArch64MCExpr::VK_DTPREL_G0_NC)
return R_CLS(TLSLD_MOVW_DTPREL_G0_NC);
if (RefKind == AArch64MCExpr::VK_TPREL_G2)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G2;
if (RefKind == AArch64MCExpr::VK_TPREL_G1)
return R_CLS(TLSLE_MOVW_TPREL_G1);
if (RefKind == AArch64MCExpr::VK_TPREL_G1_NC)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC;
if (RefKind == AArch64MCExpr::VK_TPREL_G0)
return R_CLS(TLSLE_MOVW_TPREL_G0);
if (RefKind == AArch64MCExpr::VK_TPREL_G0_NC)
return R_CLS(TLSLE_MOVW_TPREL_G0_NC);
if (RefKind == AArch64MCExpr::VK_GOTTPREL_G1)
return ELF::R_AARCH64_TLSIE_MOVW_GOTTPREL_G1;
if (RefKind == AArch64MCExpr::VK_GOTTPREL_G0_NC)
return ELF::R_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for movz/movk instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_tlsdesc_call:
return R_CLS(TLSDESC_CALL);
default:
Ctx.reportError(Fixup.getLoc(), "Unknown ELF relocation type");
return ELF::R_AARCH64_NONE;
}
}
llvm_unreachable("Unimplemented fixup -> relocation");
}
unsigned X86WinCOFFObjectWriter::getRelocType(MCContext &Ctx,
const MCValue &Target,
const MCFixup &Fixup,
bool IsCrossSection,
const MCAsmBackend &MAB) const {
unsigned FixupKind = Fixup.getKind();
if (IsCrossSection) {
if (FixupKind != FK_Data_4 && FixupKind != llvm::X86::reloc_signed_4byte) {
Ctx.reportError(Fixup.getLoc(), "Cannot represent this expression");
return COFF::IMAGE_REL_AMD64_ADDR32;
}
FixupKind = FK_PCRel_4;
}
MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ?
MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
if (getMachine() == COFF::IMAGE_FILE_MACHINE_AMD64) {
switch (FixupKind) {
case FK_PCRel_4:
case X86::reloc_riprel_4byte:
case X86::reloc_riprel_4byte_movq_load:
case X86::reloc_riprel_4byte_relax:
case X86::reloc_riprel_4byte_relax_rex:
case X86::reloc_branch_4byte_pcrel:
return COFF::IMAGE_REL_AMD64_REL32;
case FK_Data_4:
case X86::reloc_signed_4byte:
case X86::reloc_signed_4byte_relax:
if (Modifier == MCSymbolRefExpr::VK_COFF_IMGREL32)
return COFF::IMAGE_REL_AMD64_ADDR32NB;
if (Modifier == MCSymbolRefExpr::VK_SECREL)
return COFF::IMAGE_REL_AMD64_SECREL;
return COFF::IMAGE_REL_AMD64_ADDR32;
case FK_Data_8:
return COFF::IMAGE_REL_AMD64_ADDR64;
case FK_SecRel_2:
return COFF::IMAGE_REL_AMD64_SECTION;
case FK_SecRel_4:
return COFF::IMAGE_REL_AMD64_SECREL;
default:
Ctx.reportError(Fixup.getLoc(), "unsupported relocation type");
return COFF::IMAGE_REL_AMD64_ADDR32;
}
} else if (getMachine() == COFF::IMAGE_FILE_MACHINE_I386) {
switch (FixupKind) {
case FK_PCRel_4:
case X86::reloc_riprel_4byte:
case X86::reloc_riprel_4byte_movq_load:
return COFF::IMAGE_REL_I386_REL32;
case FK_Data_4:
case X86::reloc_signed_4byte:
case X86::reloc_signed_4byte_relax:
if (Modifier == MCSymbolRefExpr::VK_COFF_IMGREL32)
return COFF::IMAGE_REL_I386_DIR32NB;
if (Modifier == MCSymbolRefExpr::VK_SECREL)
return COFF::IMAGE_REL_AMD64_SECREL;
return COFF::IMAGE_REL_I386_DIR32;
case FK_SecRel_2:
return COFF::IMAGE_REL_I386_SECTION;
case FK_SecRel_4:
return COFF::IMAGE_REL_I386_SECREL;
default:
Ctx.reportError(Fixup.getLoc(), "unsupported relocation type");
return COFF::IMAGE_REL_I386_DIR32;
}
} else
llvm_unreachable("Unsupported COFF machine type.");
}
static unsigned adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
MCContext *Ctx = NULL) {
unsigned Kind = Fixup.getKind();
switch (Kind) {
default:
llvm_unreachable("Unknown fixup kind!");
case FK_Data_1:
case FK_Data_2:
case FK_Data_4:
return Value;
case ARM::fixup_arm_movt_hi16:
Value >>= 16;
// Fallthrough
case ARM::fixup_arm_movw_lo16:
case ARM::fixup_arm_movt_hi16_pcrel:
case ARM::fixup_arm_movw_lo16_pcrel: {
unsigned Hi4 = (Value & 0xF000) >> 12;
unsigned Lo12 = Value & 0x0FFF;
// inst{19-16} = Hi4;
// inst{11-0} = Lo12;
Value = (Hi4 << 16) | (Lo12);
return Value;
}
case ARM::fixup_t2_movt_hi16:
Value >>= 16;
// Fallthrough
case ARM::fixup_t2_movw_lo16:
case ARM::fixup_t2_movt_hi16_pcrel: //FIXME: Shouldn't this be shifted like
// the other hi16 fixup?
case ARM::fixup_t2_movw_lo16_pcrel: {
unsigned Hi4 = (Value & 0xF000) >> 12;
unsigned i = (Value & 0x800) >> 11;
unsigned Mid3 = (Value & 0x700) >> 8;
unsigned Lo8 = Value & 0x0FF;
// inst{19-16} = Hi4;
// inst{26} = i;
// inst{14-12} = Mid3;
// inst{7-0} = Lo8;
Value = (Hi4 << 16) | (i << 26) | (Mid3 << 12) | (Lo8);
uint64_t swapped = (Value & 0xFFFF0000) >> 16;
swapped |= (Value & 0x0000FFFF) << 16;
return swapped;
}
case ARM::fixup_arm_ldst_pcrel_12:
// ARM PC-relative values are offset by 8.
Value -= 4;
// FALLTHROUGH
case ARM::fixup_t2_ldst_pcrel_12: {
// Offset by 4, adjusted by two due to the half-word ordering of thumb.
Value -= 4;
bool isAdd = true;
if ((int64_t)Value < 0) {
Value = -Value;
isAdd = false;
}
if (Ctx && Value >= 4096)
Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value |= isAdd << 23;
// Same addressing mode as fixup_arm_pcrel_10,
// but with 16-bit halfwords swapped.
if (Kind == ARM::fixup_t2_ldst_pcrel_12) {
uint64_t swapped = (Value & 0xFFFF0000) >> 16;
swapped |= (Value & 0x0000FFFF) << 16;
return swapped;
}
return Value;
}
case ARM::fixup_thumb_adr_pcrel_10:
return ((Value - 4) >> 2) & 0xff;
case ARM::fixup_arm_adr_pcrel_12: {
// ARM PC-relative values are offset by 8.
Value -= 8;
unsigned opc = 4; // bits {24-21}. Default to add: 0b0100
if ((int64_t)Value < 0) {
Value = -Value;
opc = 2; // 0b0010
}
if (Ctx && ARM_AM::getSOImmVal(Value) == -1)
Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
// Encode the immediate and shift the opcode into place.
return ARM_AM::getSOImmVal(Value) | (opc << 21);
}
case ARM::fixup_t2_adr_pcrel_12: {
Value -= 4;
unsigned opc = 0;
if ((int64_t)Value < 0) {
Value = -Value;
opc = 5;
}
uint32_t out = (opc << 21);
out |= (Value & 0x800) << 15;
out |= (Value & 0x700) << 4;
out |= (Value & 0x0FF);
uint64_t swapped = (out & 0xFFFF0000) >> 16;
swapped |= (out & 0x0000FFFF) << 16;
return swapped;
}
case ARM::fixup_arm_condbranch:
case ARM::fixup_arm_uncondbranch:
case ARM::fixup_arm_uncondbl:
case ARM::fixup_arm_condbl:
case ARM::fixup_arm_blx:
// These values don't encode the low two bits since they're always zero.
// Offset by 8 just as above.
return 0xffffff & ((Value - 8) >> 2);
case ARM::fixup_t2_uncondbranch: {
Value = Value - 4;
Value >>= 1; // Low bit is not encoded.
uint32_t out = 0;
bool I = Value & 0x800000;
bool J1 = Value & 0x400000;
bool J2 = Value & 0x200000;
J1 ^= I;
J2 ^= I;
out |= I << 26; // S bit
out |= !J1 << 13; // J1 bit
out |= !J2 << 11; // J2 bit
out |= (Value & 0x1FF800) << 5; // imm6 field
out |= (Value & 0x0007FF); // imm11 field
uint64_t swapped = (out & 0xFFFF0000) >> 16;
swapped |= (out & 0x0000FFFF) << 16;
return swapped;
}
case ARM::fixup_t2_condbranch: {
Value = Value - 4;
Value >>= 1; // Low bit is not encoded.
uint64_t out = 0;
out |= (Value & 0x80000) << 7; // S bit
out |= (Value & 0x40000) >> 7; // J2 bit
out |= (Value & 0x20000) >> 4; // J1 bit
out |= (Value & 0x1F800) << 5; // imm6 field
out |= (Value & 0x007FF); // imm11 field
uint32_t swapped = (out & 0xFFFF0000) >> 16;
swapped |= (out & 0x0000FFFF) << 16;
return swapped;
}
case ARM::fixup_arm_thumb_bl: {
// The value doesn't encode the low bit (always zero) and is offset by
// four. The 32-bit immediate value is encoded as
// imm32 = SignExtend(S:I1:I2:imm10:imm11:0)
// where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
// The value is encoded into disjoint bit positions in the destination
// opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
// J = either J1 or J2 bit
//
// BL: xxxxxSIIIIIIIIII xxJxJIIIIIIIIIII
//
// Note that the halfwords are stored high first, low second; so we need
// to transpose the fixup value here to map properly.
uint32_t offset = (Value - 4) >> 1;
uint32_t signBit = (offset & 0x800000) >> 23;
uint32_t I1Bit = (offset & 0x400000) >> 22;
uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
uint32_t I2Bit = (offset & 0x200000) >> 21;
uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
uint32_t imm10Bits = (offset & 0x1FF800) >> 11;
uint32_t imm11Bits = (offset & 0x000007FF);
uint32_t Binary = 0;
uint32_t firstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10Bits);
uint32_t secondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
(uint16_t)imm11Bits);
Binary |= secondHalf << 16;
Binary |= firstHalf;
return Binary;
}
case ARM::fixup_arm_thumb_blx: {
// The value doesn't encode the low two bits (always zero) and is offset by
// four (see fixup_arm_thumb_cp). The 32-bit immediate value is encoded as
// imm32 = SignExtend(S:I1:I2:imm10H:imm10L:00)
// where I1 = NOT(J1 ^ S) and I2 = NOT(J2 ^ S).
// The value is encoded into disjoint bit positions in the destination
// opcode. x = unchanged, I = immediate value bit, S = sign extension bit,
// J = either J1 or J2 bit, 0 = zero.
//
// BLX: xxxxxSIIIIIIIIII xxJxJIIIIIIIIII0
//
// Note that the halfwords are stored high first, low second; so we need
// to transpose the fixup value here to map properly.
uint32_t offset = (Value - 2) >> 2;
uint32_t signBit = (offset & 0x400000) >> 22;
uint32_t I1Bit = (offset & 0x200000) >> 21;
uint32_t J1Bit = (I1Bit ^ 0x1) ^ signBit;
uint32_t I2Bit = (offset & 0x100000) >> 20;
uint32_t J2Bit = (I2Bit ^ 0x1) ^ signBit;
uint32_t imm10HBits = (offset & 0xFFC00) >> 10;
uint32_t imm10LBits = (offset & 0x3FF);
uint32_t Binary = 0;
uint32_t firstHalf = (((uint16_t)signBit << 10) | (uint16_t)imm10HBits);
uint32_t secondHalf = (((uint16_t)J1Bit << 13) | ((uint16_t)J2Bit << 11) |
((uint16_t)imm10LBits) << 1);
Binary |= secondHalf << 16;
Binary |= firstHalf;
return Binary;
}
case ARM::fixup_arm_thumb_cp:
// Offset by 4, and don't encode the low two bits. Two bytes of that
// 'off by 4' is implicitly handled by the half-word ordering of the
// Thumb encoding, so we only need to adjust by 2 here.
return ((Value - 2) >> 2) & 0xff;
case ARM::fixup_arm_thumb_cb: {
// Offset by 4 and don't encode the lower bit, which is always 0.
uint32_t Binary = (Value - 4) >> 1;
return ((Binary & 0x20) << 4) | ((Binary & 0x1f) << 3);
}
case ARM::fixup_arm_thumb_br:
// Offset by 4 and don't encode the lower bit, which is always 0.
return ((Value - 4) >> 1) & 0x7ff;
case ARM::fixup_arm_thumb_bcc:
// Offset by 4 and don't encode the lower bit, which is always 0.
return ((Value - 4) >> 1) & 0xff;
case ARM::fixup_arm_pcrel_10_unscaled: {
Value = Value - 8; // ARM fixups offset by an additional word and don't
// need to adjust for the half-word ordering.
bool isAdd = true;
if ((int64_t)Value < 0) {
Value = -Value;
isAdd = false;
}
// The value has the low 4 bits encoded in [3:0] and the high 4 in [11:8].
if (Ctx && Value >= 256)
Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value = (Value & 0xf) | ((Value & 0xf0) << 4);
return Value | (isAdd << 23);
}
case ARM::fixup_arm_pcrel_10:
Value = Value - 4; // ARM fixups offset by an additional word and don't
// need to adjust for the half-word ordering.
// Fall through.
case ARM::fixup_t2_pcrel_10: {
// Offset by 4, adjusted by two due to the half-word ordering of thumb.
Value = Value - 4;
bool isAdd = true;
if ((int64_t)Value < 0) {
Value = -Value;
isAdd = false;
}
// These values don't encode the low two bits since they're always zero.
Value >>= 2;
if (Ctx && Value >= 256)
Ctx->FatalError(Fixup.getLoc(), "out of range pc-relative fixup value");
Value |= isAdd << 23;
// Same addressing mode as fixup_arm_pcrel_10, but with 16-bit halfwords
// swapped.
if (Kind == ARM::fixup_t2_pcrel_10) {
uint32_t swapped = (Value & 0xFFFF0000) >> 16;
swapped |= (Value & 0x0000FFFF) << 16;
return swapped;
}
return Value;
}
void ARMMachObjectWriter::
RecordARMScatteredHalfRelocation(MachObjectWriter *Writer,
const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
const MCFixup &Fixup,
MCValue Target,
uint64_t &FixedValue) {
uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
unsigned Type = MachO::ARM_RELOC_HALF;
// See <reloc.h>.
const MCSymbol *A = &Target.getSymA()->getSymbol();
const MCSymbolData *A_SD = &Asm.getSymbolData(*A);
if (!A_SD->getFragment())
Asm.getContext().FatalError(Fixup.getLoc(),
"symbol '" + A->getName() +
"' can not be undefined in a subtraction expression");
uint32_t Value = Writer->getSymbolAddress(A_SD, Layout);
uint32_t Value2 = 0;
uint64_t SecAddr =
Writer->getSectionAddress(A_SD->getFragment()->getParent());
FixedValue += SecAddr;
if (const MCSymbolRefExpr *B = Target.getSymB()) {
const MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol());
if (!B_SD->getFragment())
Asm.getContext().FatalError(Fixup.getLoc(),
"symbol '" + B->getSymbol().getName() +
"' can not be undefined in a subtraction expression");
// Select the appropriate difference relocation type.
Type = MachO::ARM_RELOC_HALF_SECTDIFF;
Value2 = Writer->getSymbolAddress(B_SD, Layout);
FixedValue -= Writer->getSectionAddress(B_SD->getFragment()->getParent());
}
// Relocations are written out in reverse order, so the PAIR comes first.
// ARM_RELOC_HALF and ARM_RELOC_HALF_SECTDIFF abuse the r_length field:
//
// For these two r_type relocations they always have a pair following them and
// the r_length bits are used differently. The encoding of the r_length is as
// follows:
// low bit of r_length:
// 0 - :lower16: for movw instructions
// 1 - :upper16: for movt instructions
// high bit of r_length:
// 0 - arm instructions
// 1 - thumb instructions
// the other half of the relocated expression is in the following pair
// relocation entry in the low 16 bits of r_address field.
unsigned ThumbBit = 0;
unsigned MovtBit = 0;
switch ((unsigned)Fixup.getKind()) {
default: break;
case ARM::fixup_arm_movt_hi16:
MovtBit = 1;
// The thumb bit shouldn't be set in the 'other-half' bit of the
// relocation, but it will be set in FixedValue if the base symbol
// is a thumb function. Clear it out here.
if (Asm.isThumbFunc(A))
FixedValue &= 0xfffffffe;
break;
case ARM::fixup_t2_movt_hi16:
if (Asm.isThumbFunc(A))
FixedValue &= 0xfffffffe;
MovtBit = 1;
// Fallthrough
case ARM::fixup_t2_movw_lo16:
ThumbBit = 1;
break;
}
if (Type == MachO::ARM_RELOC_HALF_SECTDIFF) {
uint32_t OtherHalf = MovtBit
? (FixedValue & 0xffff) : ((FixedValue & 0xffff0000) >> 16);
MachO::any_relocation_info MRE;
MRE.r_word0 = ((OtherHalf << 0) |
(MachO::ARM_RELOC_PAIR << 24) |
(MovtBit << 28) |
(ThumbBit << 29) |
(IsPCRel << 30) |
MachO::R_SCATTERED);
MRE.r_word1 = Value2;
Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
}
void AArch64MachObjectWriter::RecordRelocation(
MachObjectWriter *Writer, MCAssembler &Asm, const MCAsmLayout &Layout,
const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target,
uint64_t &FixedValue) {
unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
// See <reloc.h>.
uint32_t FixupOffset = Layout.getFragmentOffset(Fragment);
unsigned Log2Size = 0;
int64_t Value = 0;
unsigned Index = 0;
unsigned Type = 0;
unsigned Kind = Fixup.getKind();
const MCSymbolData *RelSymbol = nullptr;
FixupOffset += Fixup.getOffset();
// AArch64 pcrel relocation addends do not include the section offset.
if (IsPCRel)
FixedValue += FixupOffset;
// ADRP fixups use relocations for the whole symbol value and only
// put the addend in the instruction itself. Clear out any value the
// generic code figured out from the sybmol definition.
if (Kind == AArch64::fixup_aarch64_pcrel_adrp_imm21)
FixedValue = 0;
// imm19 relocations are for conditional branches, which require
// assembler local symbols. If we got here, that's not what we have,
// so complain loudly.
if (Kind == AArch64::fixup_aarch64_pcrel_branch19) {
Asm.getContext().FatalError(Fixup.getLoc(),
"conditional branch requires assembler-local"
" label. '" +
Target.getSymA()->getSymbol().getName() +
"' is external.");
return;
}
// 14-bit branch relocations should only target internal labels, and so
// should never get here.
if (Kind == AArch64::fixup_aarch64_pcrel_branch14) {
Asm.getContext().FatalError(Fixup.getLoc(),
"Invalid relocation on conditional branch!");
return;
}
if (!getAArch64FixupKindMachOInfo(Fixup, Type, Target.getSymA(), Log2Size,
Asm)) {
Asm.getContext().FatalError(Fixup.getLoc(), "unknown AArch64 fixup kind!");
return;
}
Value = Target.getConstant();
if (Target.isAbsolute()) { // constant
// FIXME: Should this always be extern?
// SymbolNum of 0 indicates the absolute section.
Type = MachO::ARM64_RELOC_UNSIGNED;
if (IsPCRel) {
Asm.getContext().FatalError(Fixup.getLoc(),
"PC relative absolute relocation!");
// FIXME: x86_64 sets the type to a branch reloc here. Should we do
// something similar?
}
} else if (Target.getSymB()) { // A - B + constant
const MCSymbol *A = &Target.getSymA()->getSymbol();
const MCSymbolData &A_SD = Asm.getSymbolData(*A);
const MCSymbolData *A_Base = Asm.getAtom(&A_SD);
const MCSymbol *B = &Target.getSymB()->getSymbol();
const MCSymbolData &B_SD = Asm.getSymbolData(*B);
const MCSymbolData *B_Base = Asm.getAtom(&B_SD);
// Check for "_foo@got - .", which comes through here as:
// Ltmp0:
// ... _foo@got - Ltmp0
if (Target.getSymA()->getKind() == MCSymbolRefExpr::VK_GOT &&
Target.getSymB()->getKind() == MCSymbolRefExpr::VK_None &&
Layout.getSymbolOffset(&B_SD) ==
Layout.getFragmentOffset(Fragment) + Fixup.getOffset()) {
// SymB is the PC, so use a PC-rel pointer-to-GOT relocation.
Type = MachO::ARM64_RELOC_POINTER_TO_GOT;
IsPCRel = 1;
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 = (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
Writer->addRelocation(A_Base, Fragment->getParent(), MRE);
return;
} else if (Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None ||
Target.getSymB()->getKind() != MCSymbolRefExpr::VK_None)
// Otherwise, neither symbol can be modified.
Asm.getContext().FatalError(Fixup.getLoc(),
"unsupported relocation of modified symbol");
// We don't support PCrel relocations of differences.
if (IsPCRel)
Asm.getContext().FatalError(Fixup.getLoc(),
"unsupported pc-relative relocation of "
"difference");
// AArch64 always uses external relocations. If there is no symbol to use as
// a base address (a local symbol with no preceding non-local symbol),
// error out.
//
// FIXME: We should probably just synthesize an external symbol and use
// that.
if (!A_Base)
Asm.getContext().FatalError(
Fixup.getLoc(),
"unsupported relocation of local symbol '" + A->getName() +
"'. Must have non-local symbol earlier in section.");
if (!B_Base)
Asm.getContext().FatalError(
Fixup.getLoc(),
"unsupported relocation of local symbol '" + B->getName() +
"'. Must have non-local symbol earlier in section.");
if (A_Base == B_Base && A_Base)
Asm.getContext().FatalError(Fixup.getLoc(),
"unsupported relocation with identical base");
Value += (!A_SD.getFragment() ? 0
: Writer->getSymbolAddress(&A_SD, Layout)) -
(!A_Base || !A_Base->getFragment()
? 0
: Writer->getSymbolAddress(A_Base, Layout));
Value -= (!B_SD.getFragment() ? 0
: Writer->getSymbolAddress(&B_SD, Layout)) -
(!B_Base || !B_Base->getFragment()
? 0
: Writer->getSymbolAddress(B_Base, Layout));
Type = MachO::ARM64_RELOC_UNSIGNED;
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 = (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
Writer->addRelocation(A_Base, Fragment->getParent(), MRE);
RelSymbol = B_Base;
Type = MachO::ARM64_RELOC_SUBTRACTOR;
} else { // A + constant
const MCSymbol *Symbol = &Target.getSymA()->getSymbol();
const MCSectionMachO &Section = static_cast<const MCSectionMachO &>(
Fragment->getParent()->getSection());
bool CanUseLocalRelocation =
canUseLocalRelocation(Section, *Symbol, Log2Size);
if (Symbol->isTemporary() && (Value || !CanUseLocalRelocation)) {
const MCSection &Sec = Symbol->getSection();
if (!Asm.getContext().getAsmInfo()->isSectionAtomizableBySymbols(Sec))
Asm.addLocalUsedInReloc(*Symbol);
}
const MCSymbolData &SD = Asm.getSymbolData(*Symbol);
const MCSymbolData *Base = Asm.getAtom(&SD);
// If the symbol is a variable and we weren't able to get a Base for it
// (i.e., it's not in the symbol table associated with a section) resolve
// the relocation based its expansion instead.
if (Symbol->isVariable() && !Base) {
// If the evaluation is an absolute value, just use that directly
// to keep things easy.
int64_t Res;
if (SD.getSymbol().getVariableValue()->EvaluateAsAbsolute(
Res, Layout, Writer->getSectionAddressMap())) {
FixedValue = Res;
return;
}
// FIXME: Will the Target we already have ever have any data in it
// we need to preserve and merge with the new Target? How about
// the FixedValue?
if (!Symbol->getVariableValue()->EvaluateAsRelocatable(Target, &Layout,
&Fixup))
Asm.getContext().FatalError(Fixup.getLoc(),
"unable to resolve variable '" +
Symbol->getName() + "'");
return RecordRelocation(Writer, Asm, Layout, Fragment, Fixup, Target,
FixedValue);
}
// Relocations inside debug sections always use local relocations when
// possible. This seems to be done because the debugger doesn't fully
// understand relocation entries and expects to find values that
// have already been fixed up.
if (Symbol->isInSection()) {
if (Section.hasAttribute(MachO::S_ATTR_DEBUG))
Base = nullptr;
}
// AArch64 uses external relocations as much as possible. For debug
// sections, and for pointer-sized relocations (.quad), we allow section
// relocations. It's code sections that run into trouble.
if (Base) {
RelSymbol = Base;
// Add the local offset, if needed.
if (Base != &SD)
Value += Layout.getSymbolOffset(&SD) - Layout.getSymbolOffset(Base);
} else if (Symbol->isInSection()) {
if (!CanUseLocalRelocation)
Asm.getContext().FatalError(
Fixup.getLoc(),
"unsupported relocation of local symbol '" + Symbol->getName() +
"'. Must have non-local symbol earlier in section.");
// Adjust the relocation to be section-relative.
// The index is the section ordinal (1-based).
const MCSectionData &SymSD =
Asm.getSectionData(SD.getSymbol().getSection());
Index = SymSD.getOrdinal() + 1;
Value += Writer->getSymbolAddress(&SD, Layout);
if (IsPCRel)
Value -= Writer->getFragmentAddress(Fragment, Layout) +
Fixup.getOffset() + (1ULL << Log2Size);
} else {
// Resolve constant variables.
if (SD.getSymbol().isVariable()) {
int64_t Res;
if (SD.getSymbol().getVariableValue()->EvaluateAsAbsolute(
Res, Layout, Writer->getSectionAddressMap())) {
FixedValue = Res;
return;
}
}
Asm.getContext().FatalError(Fixup.getLoc(),
"unsupported relocation of variable '" +
Symbol->getName() + "'");
}
}
// If the relocation kind is Branch26, Page21, or Pageoff12, any addend
// is represented via an Addend relocation, not encoded directly into
// the instruction.
if ((Type == MachO::ARM64_RELOC_BRANCH26 ||
Type == MachO::ARM64_RELOC_PAGE21 ||
Type == MachO::ARM64_RELOC_PAGEOFF12) &&
Value) {
assert((Value & 0xff000000) == 0 && "Added relocation out of range!");
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 =
(Index << 0) | (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
Writer->addRelocation(RelSymbol, Fragment->getParent(), MRE);
// Now set up the Addend relocation.
Type = MachO::ARM64_RELOC_ADDEND;
Index = Value;
RelSymbol = nullptr;
IsPCRel = 0;
Log2Size = 2;
// Put zero into the instruction itself. The addend is in the relocation.
Value = 0;
}
// If there's any addend left to handle, encode it in the instruction.
FixedValue = Value;
// struct relocation_info (8 bytes)
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 =
(Index << 0) | (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
Writer->addRelocation(RelSymbol, Fragment->getParent(), MRE);
}
bool AArch64MachObjectWriter::getAArch64FixupKindMachOInfo(
const MCFixup &Fixup, unsigned &RelocType, const MCSymbolRefExpr *Sym,
unsigned &Log2Size, const MCAssembler &Asm) {
RelocType = unsigned(MachO::ARM64_RELOC_UNSIGNED);
Log2Size = ~0U;
switch ((unsigned)Fixup.getKind()) {
default:
return false;
case FK_Data_1:
Log2Size = llvm::Log2_32(1);
return true;
case FK_Data_2:
Log2Size = llvm::Log2_32(2);
return true;
case FK_Data_4:
Log2Size = llvm::Log2_32(4);
if (Sym->getKind() == MCSymbolRefExpr::VK_GOT)
RelocType = unsigned(MachO::ARM64_RELOC_POINTER_TO_GOT);
return true;
case FK_Data_8:
Log2Size = llvm::Log2_32(8);
if (Sym->getKind() == MCSymbolRefExpr::VK_GOT)
RelocType = unsigned(MachO::ARM64_RELOC_POINTER_TO_GOT);
return true;
case AArch64::fixup_aarch64_add_imm12:
case AArch64::fixup_aarch64_ldst_imm12_scale1:
case AArch64::fixup_aarch64_ldst_imm12_scale2:
case AArch64::fixup_aarch64_ldst_imm12_scale4:
case AArch64::fixup_aarch64_ldst_imm12_scale8:
case AArch64::fixup_aarch64_ldst_imm12_scale16:
Log2Size = llvm::Log2_32(4);
switch (Sym->getKind()) {
default:
llvm_unreachable("Unexpected symbol reference variant kind!");
case MCSymbolRefExpr::VK_PAGEOFF:
RelocType = unsigned(MachO::ARM64_RELOC_PAGEOFF12);
return true;
case MCSymbolRefExpr::VK_GOTPAGEOFF:
RelocType = unsigned(MachO::ARM64_RELOC_GOT_LOAD_PAGEOFF12);
return true;
case MCSymbolRefExpr::VK_TLVPPAGEOFF:
RelocType = unsigned(MachO::ARM64_RELOC_TLVP_LOAD_PAGEOFF12);
return true;
}
case AArch64::fixup_aarch64_pcrel_adrp_imm21:
Log2Size = llvm::Log2_32(4);
// This encompasses the relocation for the whole 21-bit value.
switch (Sym->getKind()) {
default:
Asm.getContext().FatalError(Fixup.getLoc(),
"ADR/ADRP relocations must be GOT relative");
case MCSymbolRefExpr::VK_PAGE:
RelocType = unsigned(MachO::ARM64_RELOC_PAGE21);
return true;
case MCSymbolRefExpr::VK_GOTPAGE:
RelocType = unsigned(MachO::ARM64_RELOC_GOT_LOAD_PAGE21);
return true;
case MCSymbolRefExpr::VK_TLVPPAGE:
RelocType = unsigned(MachO::ARM64_RELOC_TLVP_LOAD_PAGE21);
return true;
}
return true;
case AArch64::fixup_aarch64_pcrel_branch26:
case AArch64::fixup_aarch64_pcrel_call26:
Log2Size = llvm::Log2_32(4);
RelocType = unsigned(MachO::ARM64_RELOC_BRANCH26);
return true;
}
}
static uint64_t adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
MCContext &Ctx) {
unsigned Kind = Fixup.getKind();
switch (Kind) {
default:
llvm_unreachable("Unknown fixup kind!");
case RISCV::fixup_riscv_got_hi20:
llvm_unreachable("Relocation should be unconditionally forced\n");
case FK_Data_1:
case FK_Data_2:
case FK_Data_4:
case FK_Data_8:
return Value;
case RISCV::fixup_riscv_lo12_i:
case RISCV::fixup_riscv_pcrel_lo12_i:
case RISCV::fixup_riscv_tprel_lo12_i:
return Value & 0xfff;
case RISCV::fixup_riscv_lo12_s:
case RISCV::fixup_riscv_pcrel_lo12_s:
case RISCV::fixup_riscv_tprel_lo12_s:
return (((Value >> 5) & 0x7f) << 25) | ((Value & 0x1f) << 7);
case RISCV::fixup_riscv_hi20:
case RISCV::fixup_riscv_pcrel_hi20:
case RISCV::fixup_riscv_tprel_hi20:
// Add 1 if bit 11 is 1, to compensate for low 12 bits being negative.
return ((Value + 0x800) >> 12) & 0xfffff;
case RISCV::fixup_riscv_jal: {
if (!isInt<21>(Value))
Ctx.reportError(Fixup.getLoc(), "fixup value out of range");
if (Value & 0x1)
Ctx.reportError(Fixup.getLoc(), "fixup value must be 2-byte aligned");
// Need to produce imm[19|10:1|11|19:12] from the 21-bit Value.
unsigned Sbit = (Value >> 20) & 0x1;
unsigned Hi8 = (Value >> 12) & 0xff;
unsigned Mid1 = (Value >> 11) & 0x1;
unsigned Lo10 = (Value >> 1) & 0x3ff;
// Inst{31} = Sbit;
// Inst{30-21} = Lo10;
// Inst{20} = Mid1;
// Inst{19-12} = Hi8;
Value = (Sbit << 19) | (Lo10 << 9) | (Mid1 << 8) | Hi8;
return Value;
}
case RISCV::fixup_riscv_branch: {
if (!isInt<13>(Value))
Ctx.reportError(Fixup.getLoc(), "fixup value out of range");
if (Value & 0x1)
Ctx.reportError(Fixup.getLoc(), "fixup value must be 2-byte aligned");
// Need to extract imm[12], imm[10:5], imm[4:1], imm[11] from the 13-bit
// Value.
unsigned Sbit = (Value >> 12) & 0x1;
unsigned Hi1 = (Value >> 11) & 0x1;
unsigned Mid6 = (Value >> 5) & 0x3f;
unsigned Lo4 = (Value >> 1) & 0xf;
// Inst{31} = Sbit;
// Inst{30-25} = Mid6;
// Inst{11-8} = Lo4;
// Inst{7} = Hi1;
Value = (Sbit << 31) | (Mid6 << 25) | (Lo4 << 8) | (Hi1 << 7);
return Value;
}
case RISCV::fixup_riscv_call:
case RISCV::fixup_riscv_call_plt: {
// Jalr will add UpperImm with the sign-extended 12-bit LowerImm,
// we need to add 0x800ULL before extract upper bits to reflect the
// effect of the sign extension.
uint64_t UpperImm = (Value + 0x800ULL) & 0xfffff000ULL;
uint64_t LowerImm = Value & 0xfffULL;
return UpperImm | ((LowerImm << 20) << 32);
}
case RISCV::fixup_riscv_rvc_jump: {
// Need to produce offset[11|4|9:8|10|6|7|3:1|5] from the 11-bit Value.
unsigned Bit11 = (Value >> 11) & 0x1;
unsigned Bit4 = (Value >> 4) & 0x1;
unsigned Bit9_8 = (Value >> 8) & 0x3;
unsigned Bit10 = (Value >> 10) & 0x1;
unsigned Bit6 = (Value >> 6) & 0x1;
unsigned Bit7 = (Value >> 7) & 0x1;
unsigned Bit3_1 = (Value >> 1) & 0x7;
unsigned Bit5 = (Value >> 5) & 0x1;
Value = (Bit11 << 10) | (Bit4 << 9) | (Bit9_8 << 7) | (Bit10 << 6) |
(Bit6 << 5) | (Bit7 << 4) | (Bit3_1 << 1) | Bit5;
return Value;
}
case RISCV::fixup_riscv_rvc_branch: {
// Need to produce offset[8|4:3], [reg 3 bit], offset[7:6|2:1|5]
unsigned Bit8 = (Value >> 8) & 0x1;
unsigned Bit7_6 = (Value >> 6) & 0x3;
unsigned Bit5 = (Value >> 5) & 0x1;
unsigned Bit4_3 = (Value >> 3) & 0x3;
unsigned Bit2_1 = (Value >> 1) & 0x3;
Value = (Bit8 << 12) | (Bit4_3 << 10) | (Bit7_6 << 5) | (Bit2_1 << 3) |
(Bit5 << 2);
return Value;
}
}
}
void ELFObjectWriter::recordRelocation(MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
const MCFixup &Fixup, MCValue Target,
uint64_t &FixedValue) {
MCAsmBackend &Backend = Asm.getBackend();
bool IsPCRel = Backend.getFixupKindInfo(Fixup.getKind()).Flags &
MCFixupKindInfo::FKF_IsPCRel;
const MCSectionELF &FixupSection = cast<MCSectionELF>(*Fragment->getParent());
uint64_t C = Target.getConstant();
uint64_t FixupOffset = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
MCContext &Ctx = Asm.getContext();
if (const MCSymbolRefExpr *RefB = Target.getSymB()) {
// Let A, B and C being the components of Target and R be the location of
// the fixup. If the fixup is not pcrel, we want to compute (A - B + C).
// If it is pcrel, we want to compute (A - B + C - R).
// In general, ELF has no relocations for -B. It can only represent (A + C)
// or (A + C - R). If B = R + K and the relocation is not pcrel, we can
// replace B to implement it: (A - R - K + C)
if (IsPCRel) {
Ctx.reportError(
Fixup.getLoc(),
"No relocation available to represent this relative expression");
return;
}
const auto &SymB = cast<MCSymbolELF>(RefB->getSymbol());
if (SymB.isUndefined()) {
Ctx.reportError(Fixup.getLoc(),
Twine("symbol '") + SymB.getName() +
"' can not be undefined in a subtraction expression");
return;
}
assert(!SymB.isAbsolute() && "Should have been folded");
const MCSection &SecB = SymB.getSection();
if (&SecB != &FixupSection) {
Ctx.reportError(Fixup.getLoc(),
"Cannot represent a difference across sections");
return;
}
uint64_t SymBOffset = Layout.getSymbolOffset(SymB);
uint64_t K = SymBOffset - FixupOffset;
IsPCRel = true;
C -= K;
}
// We either rejected the fixup or folded B into C at this point.
const MCSymbolRefExpr *RefA = Target.getSymA();
const auto *SymA = RefA ? cast<MCSymbolELF>(&RefA->getSymbol()) : nullptr;
bool ViaWeakRef = false;
if (SymA && SymA->isVariable()) {
const MCExpr *Expr = SymA->getVariableValue();
if (const auto *Inner = dyn_cast<MCSymbolRefExpr>(Expr)) {
if (Inner->getKind() == MCSymbolRefExpr::VK_WEAKREF) {
SymA = cast<MCSymbolELF>(&Inner->getSymbol());
ViaWeakRef = true;
}
}
}
unsigned Type = getRelocType(Ctx, Target, Fixup, IsPCRel);
uint64_t OriginalC = C;
bool RelocateWithSymbol = shouldRelocateWithSymbol(Asm, RefA, SymA, C, Type);
if (!RelocateWithSymbol && SymA && !SymA->isUndefined())
C += Layout.getSymbolOffset(*SymA);
uint64_t Addend = 0;
if (hasRelocationAddend()) {
Addend = C;
C = 0;
}
FixedValue = C;
if (!RelocateWithSymbol) {
const MCSection *SecA =
(SymA && !SymA->isUndefined()) ? &SymA->getSection() : nullptr;
auto *ELFSec = cast_or_null<MCSectionELF>(SecA);
const auto *SectionSymbol =
ELFSec ? cast<MCSymbolELF>(ELFSec->getBeginSymbol()) : nullptr;
if (SectionSymbol)
SectionSymbol->setUsedInReloc();
ELFRelocationEntry Rec(FixupOffset, SectionSymbol, Type, Addend, SymA,
OriginalC);
Relocations[&FixupSection].push_back(Rec);
return;
}
const auto *RenamedSymA = SymA;
if (SymA) {
if (const MCSymbolELF *R = Renames.lookup(SymA))
RenamedSymA = R;
if (ViaWeakRef)
RenamedSymA->setIsWeakrefUsedInReloc();
else
RenamedSymA->setUsedInReloc();
}
ELFRelocationEntry Rec(FixupOffset, RenamedSymA, Type, Addend, SymA,
OriginalC);
Relocations[&FixupSection].push_back(Rec);
}
bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout,
const MCFixup &Fixup, const MCFragment *DF,
MCValue &Target, uint64_t &Value) const {
++stats::evaluateFixup;
// FIXME: This code has some duplication with recordRelocation. We should
// probably merge the two into a single callback that tries to evaluate a
// fixup and records a relocation if one is needed.
const MCExpr *Expr = Fixup.getValue();
if (!Expr->evaluateAsRelocatable(Target, &Layout, &Fixup))
getContext().reportFatalError(Fixup.getLoc(), "expected relocatable expression");
bool IsPCRel = Backend.getFixupKindInfo(
Fixup.getKind()).Flags & MCFixupKindInfo::FKF_IsPCRel;
bool IsResolved;
if (IsPCRel) {
if (Target.getSymB()) {
IsResolved = false;
} else if (!Target.getSymA()) {
IsResolved = false;
} else {
const MCSymbolRefExpr *A = Target.getSymA();
const MCSymbol &SA = A->getSymbol();
if (A->getKind() != MCSymbolRefExpr::VK_None || SA.isUndefined()) {
IsResolved = false;
} else {
IsResolved = getWriter().isSymbolRefDifferenceFullyResolvedImpl(
*this, SA, *DF, false, true);
}
}
} else {
IsResolved = Target.isAbsolute();
}
Value = Target.getConstant();
if (const MCSymbolRefExpr *A = Target.getSymA()) {
const MCSymbol &Sym = A->getSymbol();
if (Sym.isDefined())
Value += Layout.getSymbolOffset(Sym);
}
if (const MCSymbolRefExpr *B = Target.getSymB()) {
const MCSymbol &Sym = B->getSymbol();
if (Sym.isDefined())
Value -= Layout.getSymbolOffset(Sym);
}
bool ShouldAlignPC = Backend.getFixupKindInfo(Fixup.getKind()).Flags &
MCFixupKindInfo::FKF_IsAlignedDownTo32Bits;
assert((ShouldAlignPC ? IsPCRel : true) &&
"FKF_IsAlignedDownTo32Bits is only allowed on PC-relative fixups!");
if (IsPCRel) {
uint32_t Offset = Layout.getFragmentOffset(DF) + Fixup.getOffset();
// A number of ARM fixups in Thumb mode require that the effective PC
// address be determined as the 32-bit aligned version of the actual offset.
if (ShouldAlignPC) Offset &= ~0x3;
Value -= Offset;
}
// Let the backend adjust the fixup value if necessary, including whether
// we need a relocation.
Backend.processFixupValue(*this, Layout, Fixup, DF, Target, Value,
IsResolved);
return IsResolved;
}
bool X86MachObjectWriter::RecordScatteredRelocation(MachObjectWriter *Writer,
const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
const MCFixup &Fixup,
MCValue Target,
unsigned Log2Size,
uint64_t &FixedValue) {
uint64_t OriginalFixedValue = FixedValue;
uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
unsigned Type = MachO::GENERIC_RELOC_VANILLA;
// See <reloc.h>.
const MCSymbol *A = &Target.getSymA()->getSymbol();
const MCSymbolData *A_SD = &Asm.getSymbolData(*A);
if (!A_SD->getFragment())
report_fatal_error("symbol '" + A->getName() +
"' can not be undefined in a subtraction expression",
false);
uint32_t Value = Writer->getSymbolAddress(A_SD, Layout);
uint64_t SecAddr = Writer->getSectionAddress(A_SD->getFragment()->getParent());
FixedValue += SecAddr;
uint32_t Value2 = 0;
if (const MCSymbolRefExpr *B = Target.getSymB()) {
const MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol());
if (!B_SD->getFragment())
report_fatal_error("symbol '" + B->getSymbol().getName() +
"' can not be undefined in a subtraction expression",
false);
// Select the appropriate difference relocation type.
//
// Note that there is no longer any semantic difference between these two
// relocation types from the linkers point of view, this is done solely for
// pedantic compatibility with 'as'.
Type = A_SD->isExternal() ? (unsigned)MachO::GENERIC_RELOC_SECTDIFF :
(unsigned)MachO::GENERIC_RELOC_LOCAL_SECTDIFF;
Value2 = Writer->getSymbolAddress(B_SD, Layout);
FixedValue -= Writer->getSectionAddress(B_SD->getFragment()->getParent());
}
// Relocations are written out in reverse order, so the PAIR comes first.
if (Type == MachO::GENERIC_RELOC_SECTDIFF ||
Type == MachO::GENERIC_RELOC_LOCAL_SECTDIFF) {
// If the offset is too large to fit in a scattered relocation,
// we're hosed. It's an unfortunate limitation of the MachO format.
if (FixupOffset > 0xffffff) {
char Buffer[32];
format("0x%x", FixupOffset).print(Buffer, sizeof(Buffer));
Asm.getContext().FatalError(Fixup.getLoc(),
Twine("Section too large, can't encode "
"r_address (") + Buffer +
") into 24 bits of scattered "
"relocation entry.");
llvm_unreachable("fatal error returned?!");
}
MachO::any_relocation_info MRE;
MRE.r_word0 = ((0 << 0) | // r_address
(MachO::GENERIC_RELOC_PAIR << 24) | // r_type
(Log2Size << 28) |
(IsPCRel << 30) |
MachO::R_SCATTERED);
MRE.r_word1 = Value2;
Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
} else {
// If the offset is more than 24-bits, it won't fit in a scattered
// relocation offset field, so we fall back to using a non-scattered
// relocation. This is a bit risky, as if the offset reaches out of
// the block and the linker is doing scattered loading on this
// symbol, things can go badly.
//
// Required for 'as' compatibility.
if (FixupOffset > 0xffffff) {
FixedValue = OriginalFixedValue;
return false;
}
}
MachO::any_relocation_info MRE;
MRE.r_word0 = ((FixupOffset << 0) |
(Type << 24) |
(Log2Size << 28) |
(IsPCRel << 30) |
MachO::R_SCATTERED);
MRE.r_word1 = Value;
Writer->addRelocation(nullptr, Fragment->getParent(), MRE);
return true;
}
unsigned ARMELFObjectWriter::GetRelocTypeInner(const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel,
MCContext &Ctx) const {
MCSymbolRefExpr::VariantKind Modifier = Target.getAccessVariant();
if (IsPCRel) {
switch ((unsigned)Fixup.getKind()) {
default:
Ctx.reportFatalError(Fixup.getLoc(), "unsupported relocation on symbol");
return ELF::R_ARM_NONE;
case FK_Data_4:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_REL32;
case MCSymbolRefExpr::VK_GOTTPOFF:
return ELF::R_ARM_TLS_IE32;
case MCSymbolRefExpr::VK_ARM_GOT_PREL:
return ELF::R_ARM_GOT_PREL;
case MCSymbolRefExpr::VK_ARM_PREL31:
return ELF::R_ARM_PREL31;
}
case ARM::fixup_arm_blx:
case ARM::fixup_arm_uncondbl:
switch (Modifier) {
case MCSymbolRefExpr::VK_PLT:
return ELF::R_ARM_CALL;
case MCSymbolRefExpr::VK_TLSCALL:
return ELF::R_ARM_TLS_CALL;
default:
return ELF::R_ARM_CALL;
}
case ARM::fixup_arm_condbl:
case ARM::fixup_arm_condbranch:
case ARM::fixup_arm_uncondbranch:
return ELF::R_ARM_JUMP24;
case ARM::fixup_t2_condbranch:
return ELF::R_ARM_THM_JUMP19;
case ARM::fixup_t2_uncondbranch:
return ELF::R_ARM_THM_JUMP24;
case ARM::fixup_arm_movt_hi16:
return ELF::R_ARM_MOVT_PREL;
case ARM::fixup_arm_movw_lo16:
return ELF::R_ARM_MOVW_PREL_NC;
case ARM::fixup_t2_movt_hi16:
return ELF::R_ARM_THM_MOVT_PREL;
case ARM::fixup_t2_movw_lo16:
return ELF::R_ARM_THM_MOVW_PREL_NC;
case ARM::fixup_arm_thumb_br:
return ELF::R_ARM_THM_JUMP11;
case ARM::fixup_arm_thumb_bcc:
return ELF::R_ARM_THM_JUMP8;
case ARM::fixup_arm_thumb_bl:
case ARM::fixup_arm_thumb_blx:
switch (Modifier) {
case MCSymbolRefExpr::VK_TLSCALL:
return ELF::R_ARM_THM_TLS_CALL;
default:
return ELF::R_ARM_THM_CALL;
}
}
}
switch ((unsigned)Fixup.getKind()) {
default:
Ctx.reportFatalError(Fixup.getLoc(), "unsupported relocation on symbol");
return ELF::R_ARM_NONE;
case FK_Data_1:
switch (Modifier) {
default:
llvm_unreachable("unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_ABS8;
}
case FK_Data_2:
switch (Modifier) {
default:
llvm_unreachable("unsupported modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_ABS16;
}
case FK_Data_4:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_ARM_NONE:
return ELF::R_ARM_NONE;
case MCSymbolRefExpr::VK_GOT:
return ELF::R_ARM_GOT_BREL;
case MCSymbolRefExpr::VK_TLSGD:
return ELF::R_ARM_TLS_GD32;
case MCSymbolRefExpr::VK_TPOFF:
return ELF::R_ARM_TLS_LE32;
case MCSymbolRefExpr::VK_GOTTPOFF:
return ELF::R_ARM_TLS_IE32;
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_ABS32;
case MCSymbolRefExpr::VK_GOTOFF:
return ELF::R_ARM_GOTOFF32;
case MCSymbolRefExpr::VK_ARM_GOT_PREL:
return ELF::R_ARM_GOT_PREL;
case MCSymbolRefExpr::VK_ARM_TARGET1:
return ELF::R_ARM_TARGET1;
case MCSymbolRefExpr::VK_ARM_TARGET2:
return ELF::R_ARM_TARGET2;
case MCSymbolRefExpr::VK_ARM_PREL31:
return ELF::R_ARM_PREL31;
case MCSymbolRefExpr::VK_ARM_SBREL:
return ELF::R_ARM_SBREL32;
case MCSymbolRefExpr::VK_ARM_TLSLDO:
return ELF::R_ARM_TLS_LDO32;
case MCSymbolRefExpr::VK_TLSCALL:
return ELF::R_ARM_TLS_CALL;
case MCSymbolRefExpr::VK_TLSDESC:
return ELF::R_ARM_TLS_GOTDESC;
case MCSymbolRefExpr::VK_TLSLDM:
return ELF::R_ARM_TLS_LDM32;
case MCSymbolRefExpr::VK_ARM_TLSDESCSEQ:
return ELF::R_ARM_TLS_DESCSEQ;
}
case ARM::fixup_arm_condbranch:
case ARM::fixup_arm_uncondbranch:
return ELF::R_ARM_JUMP24;
case ARM::fixup_arm_movt_hi16:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_MOVT_ABS;
case MCSymbolRefExpr::VK_ARM_SBREL:
return ELF::R_ARM_MOVT_BREL;
}
case ARM::fixup_arm_movw_lo16:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_MOVW_ABS_NC;
case MCSymbolRefExpr::VK_ARM_SBREL:
return ELF::R_ARM_MOVW_BREL_NC;
}
case ARM::fixup_t2_movt_hi16:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_THM_MOVT_ABS;
case MCSymbolRefExpr::VK_ARM_SBREL:
return ELF::R_ARM_THM_MOVT_BREL;
}
case ARM::fixup_t2_movw_lo16:
switch (Modifier) {
default:
llvm_unreachable("Unsupported Modifier");
case MCSymbolRefExpr::VK_None:
return ELF::R_ARM_THM_MOVW_ABS_NC;
case MCSymbolRefExpr::VK_ARM_SBREL:
return ELF::R_ARM_THM_MOVW_BREL_NC;
}
}
}
unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
const MCValue &Target,
const MCFixup &Fixup,
bool IsPCRel) const {
AArch64MCExpr::VariantKind RefKind =
static_cast<AArch64MCExpr::VariantKind>(Target.getRefKind());
AArch64MCExpr::VariantKind SymLoc = AArch64MCExpr::getSymbolLoc(RefKind);
bool IsNC = AArch64MCExpr::isNotChecked(RefKind);
assert((!Target.getSymA() ||
Target.getSymA()->getKind() == MCSymbolRefExpr::VK_None) &&
"Should only be expression-level modifiers here");
assert((!Target.getSymB() ||
Target.getSymB()->getKind() == MCSymbolRefExpr::VK_None) &&
"Should only be expression-level modifiers here");
if (IsPCRel) {
switch ((unsigned)Fixup.getKind()) {
case FK_Data_1:
Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
return ELF::R_AARCH64_NONE;
case FK_Data_2:
return ELF::R_AARCH64_PREL16;
case FK_Data_4:
return ELF::R_AARCH64_PREL32;
case FK_Data_8:
return ELF::R_AARCH64_PREL64;
case AArch64::fixup_aarch64_pcrel_adr_imm21:
assert(SymLoc == AArch64MCExpr::VK_NONE && "unexpected ADR relocation");
return ELF::R_AARCH64_ADR_PREL_LO21;
case AArch64::fixup_aarch64_pcrel_adrp_imm21:
if (SymLoc == AArch64MCExpr::VK_ABS && !IsNC)
return ELF::R_AARCH64_ADR_PREL_PG_HI21;
if (SymLoc == AArch64MCExpr::VK_GOT && !IsNC)
return ELF::R_AARCH64_ADR_GOT_PAGE;
if (SymLoc == AArch64MCExpr::VK_GOTTPREL && !IsNC)
return ELF::R_AARCH64_TLSIE_ADR_GOTTPREL_PAGE21;
if (SymLoc == AArch64MCExpr::VK_TLSDESC && !IsNC)
return ELF::R_AARCH64_TLSDESC_ADR_PAGE21;
Ctx.reportError(Fixup.getLoc(),
"invalid symbol kind for ADRP relocation");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_pcrel_branch26:
return ELF::R_AARCH64_JUMP26;
case AArch64::fixup_aarch64_pcrel_call26:
return ELF::R_AARCH64_CALL26;
case AArch64::fixup_aarch64_ldr_pcrel_imm19:
if (SymLoc == AArch64MCExpr::VK_GOTTPREL)
return ELF::R_AARCH64_TLSIE_LD_GOTTPREL_PREL19;
return ELF::R_AARCH64_LD_PREL_LO19;
case AArch64::fixup_aarch64_pcrel_branch14:
return ELF::R_AARCH64_TSTBR14;
case AArch64::fixup_aarch64_pcrel_branch19:
return ELF::R_AARCH64_CONDBR19;
default:
Ctx.reportError(Fixup.getLoc(), "Unsupported pc-relative fixup kind");
return ELF::R_AARCH64_NONE;
}
} else {
switch ((unsigned)Fixup.getKind()) {
case FK_Data_1:
Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
return ELF::R_AARCH64_NONE;
case FK_Data_2:
return ELF::R_AARCH64_ABS16;
case FK_Data_4:
return ELF::R_AARCH64_ABS32;
case FK_Data_8:
return ELF::R_AARCH64_ABS64;
case AArch64::fixup_aarch64_add_imm12:
if (RefKind == AArch64MCExpr::VK_DTPREL_HI12)
return ELF::R_AARCH64_TLSLD_ADD_DTPREL_HI12;
if (RefKind == AArch64MCExpr::VK_TPREL_HI12)
return ELF::R_AARCH64_TLSLE_ADD_TPREL_HI12;
if (RefKind == AArch64MCExpr::VK_DTPREL_LO12_NC)
return ELF::R_AARCH64_TLSLD_ADD_DTPREL_LO12_NC;
if (RefKind == AArch64MCExpr::VK_DTPREL_LO12)
return ELF::R_AARCH64_TLSLD_ADD_DTPREL_LO12;
if (RefKind == AArch64MCExpr::VK_TPREL_LO12_NC)
return ELF::R_AARCH64_TLSLE_ADD_TPREL_LO12_NC;
if (RefKind == AArch64MCExpr::VK_TPREL_LO12)
return ELF::R_AARCH64_TLSLE_ADD_TPREL_LO12;
if (RefKind == AArch64MCExpr::VK_TLSDESC_LO12)
return ELF::R_AARCH64_TLSDESC_ADD_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_ADD_ABS_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for add (uimm12) instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale1:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_LDST8_ABS_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return ELF::R_AARCH64_TLSLD_LDST8_DTPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return ELF::R_AARCH64_TLSLD_LDST8_DTPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return ELF::R_AARCH64_TLSLE_LDST8_TPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return ELF::R_AARCH64_TLSLE_LDST8_TPREL_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 8-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale2:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_LDST16_ABS_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return ELF::R_AARCH64_TLSLD_LDST16_DTPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return ELF::R_AARCH64_TLSLD_LDST16_DTPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return ELF::R_AARCH64_TLSLE_LDST16_TPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return ELF::R_AARCH64_TLSLE_LDST16_TPREL_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 16-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale4:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_LDST32_ABS_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return ELF::R_AARCH64_TLSLD_LDST32_DTPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return ELF::R_AARCH64_TLSLD_LDST32_DTPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return ELF::R_AARCH64_TLSLE_LDST32_TPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return ELF::R_AARCH64_TLSLE_LDST32_TPREL_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 32-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale8:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_LDST64_ABS_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_GOT && IsNC)
return ELF::R_AARCH64_LD64_GOT_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_DTPREL && !IsNC)
return ELF::R_AARCH64_TLSLD_LDST64_DTPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_DTPREL && IsNC)
return ELF::R_AARCH64_TLSLD_LDST64_DTPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_TPREL && !IsNC)
return ELF::R_AARCH64_TLSLE_LDST64_TPREL_LO12;
if (SymLoc == AArch64MCExpr::VK_TPREL && IsNC)
return ELF::R_AARCH64_TLSLE_LDST64_TPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_GOTTPREL && IsNC)
return ELF::R_AARCH64_TLSIE_LD64_GOTTPREL_LO12_NC;
if (SymLoc == AArch64MCExpr::VK_TLSDESC && IsNC)
return ELF::R_AARCH64_TLSDESC_LD64_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 64-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_ldst_imm12_scale16:
if (SymLoc == AArch64MCExpr::VK_ABS && IsNC)
return ELF::R_AARCH64_LDST128_ABS_LO12_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for 128-bit load/store instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_movw:
if (RefKind == AArch64MCExpr::VK_ABS_G3)
return ELF::R_AARCH64_MOVW_UABS_G3;
if (RefKind == AArch64MCExpr::VK_ABS_G2)
return ELF::R_AARCH64_MOVW_UABS_G2;
if (RefKind == AArch64MCExpr::VK_ABS_G2_S)
return ELF::R_AARCH64_MOVW_SABS_G2;
if (RefKind == AArch64MCExpr::VK_ABS_G2_NC)
return ELF::R_AARCH64_MOVW_UABS_G2_NC;
if (RefKind == AArch64MCExpr::VK_ABS_G1)
return ELF::R_AARCH64_MOVW_UABS_G1;
if (RefKind == AArch64MCExpr::VK_ABS_G1_S)
return ELF::R_AARCH64_MOVW_SABS_G1;
if (RefKind == AArch64MCExpr::VK_ABS_G1_NC)
return ELF::R_AARCH64_MOVW_UABS_G1_NC;
if (RefKind == AArch64MCExpr::VK_ABS_G0)
return ELF::R_AARCH64_MOVW_UABS_G0;
if (RefKind == AArch64MCExpr::VK_ABS_G0_S)
return ELF::R_AARCH64_MOVW_SABS_G0;
if (RefKind == AArch64MCExpr::VK_ABS_G0_NC)
return ELF::R_AARCH64_MOVW_UABS_G0_NC;
if (RefKind == AArch64MCExpr::VK_DTPREL_G2)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G2;
if (RefKind == AArch64MCExpr::VK_DTPREL_G1)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G1;
if (RefKind == AArch64MCExpr::VK_DTPREL_G1_NC)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G1_NC;
if (RefKind == AArch64MCExpr::VK_DTPREL_G0)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G0;
if (RefKind == AArch64MCExpr::VK_DTPREL_G0_NC)
return ELF::R_AARCH64_TLSLD_MOVW_DTPREL_G0_NC;
if (RefKind == AArch64MCExpr::VK_TPREL_G2)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G2;
if (RefKind == AArch64MCExpr::VK_TPREL_G1)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G1;
if (RefKind == AArch64MCExpr::VK_TPREL_G1_NC)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G1_NC;
if (RefKind == AArch64MCExpr::VK_TPREL_G0)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G0;
if (RefKind == AArch64MCExpr::VK_TPREL_G0_NC)
return ELF::R_AARCH64_TLSLE_MOVW_TPREL_G0_NC;
if (RefKind == AArch64MCExpr::VK_GOTTPREL_G1)
return ELF::R_AARCH64_TLSIE_MOVW_GOTTPREL_G1;
if (RefKind == AArch64MCExpr::VK_GOTTPREL_G0_NC)
return ELF::R_AARCH64_TLSIE_MOVW_GOTTPREL_G0_NC;
Ctx.reportError(Fixup.getLoc(),
"invalid fixup for movz/movk instruction");
return ELF::R_AARCH64_NONE;
case AArch64::fixup_aarch64_tlsdesc_call:
return ELF::R_AARCH64_TLSDESC_CALL;
default:
Ctx.reportError(Fixup.getLoc(), "Unknown ELF relocation type");
return ELF::R_AARCH64_NONE;
}
}
llvm_unreachable("Unimplemented fixup -> relocation");
}
void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
const MCFixup &Fixup,
MCValue Target,
uint64_t &FixedValue) {
assert(Target.getSymA() != NULL && "Relocation must reference a symbol!");
const MCSymbol &Symbol = Target.getSymA()->getSymbol();
const MCSymbol &A = Symbol.AliasedSymbol();
if (!Asm.hasSymbolData(A))
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + A.getName() + "' can not be undefined");
MCSymbolData &A_SD = Asm.getSymbolData(A);
MCSectionData const *SectionData = Fragment->getParent();
// Mark this symbol as requiring an entry in the symbol table.
assert(SectionMap.find(&SectionData->getSection()) != SectionMap.end() &&
"Section must already have been defined in ExecutePostLayoutBinding!");
assert(SymbolMap.find(&A_SD.getSymbol()) != SymbolMap.end() &&
"Symbol must already have been defined in ExecutePostLayoutBinding!");
COFFSection *coff_section = SectionMap[&SectionData->getSection()];
COFFSymbol *coff_symbol = SymbolMap[&A_SD.getSymbol()];
const MCSymbolRefExpr *SymB = Target.getSymB();
bool CrossSection = false;
if (SymB) {
const MCSymbol *B = &SymB->getSymbol();
MCSymbolData &B_SD = Asm.getSymbolData(*B);
if (!B_SD.getFragment())
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + B->getName() +
"' can not be undefined in a subtraction expression");
if (!A_SD.getFragment())
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + Symbol.getName() +
"' can not be undefined in a subtraction expression");
CrossSection = &Symbol.getSection() != &B->getSection();
// Offset of the symbol in the section
int64_t a = Layout.getSymbolOffset(&B_SD);
// Ofeset of the relocation in the section
int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
FixedValue = b - a;
// In the case where we have SymbA and SymB, we just need to store the delta
// between the two symbols. Update FixedValue to account for the delta, and
// skip recording the relocation.
if (!CrossSection)
return;
} else {
FixedValue = Target.getConstant();
}
COFFRelocation Reloc;
Reloc.Data.SymbolTableIndex = 0;
Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment);
// Turn relocations for temporary symbols into section relocations.
if (coff_symbol->MCData->getSymbol().isTemporary() || CrossSection) {
Reloc.Symb = coff_symbol->Section->Symbol;
FixedValue += Layout.getFragmentOffset(coff_symbol->MCData->Fragment)
+ coff_symbol->MCData->getOffset();
} else
Reloc.Symb = coff_symbol;
++Reloc.Symb->Relocations;
Reloc.Data.VirtualAddress += Fixup.getOffset();
Reloc.Data.Type = TargetObjectWriter->getRelocType(Target, Fixup,
CrossSection);
// FIXME: Can anyone explain what this does other than adjust for the size
// of the offset?
if (Reloc.Data.Type == COFF::IMAGE_REL_AMD64_REL32 ||
Reloc.Data.Type == COFF::IMAGE_REL_I386_REL32)
FixedValue += 4;
coff_section->Relocations.push_back(Reloc);
}
void WinCOFFObjectWriter::RecordRelocation(const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
const MCFixup &Fixup,
MCValue Target,
bool &IsPCRel,
uint64_t &FixedValue) {
assert(Target.getSymA() && "Relocation must reference a symbol!");
const MCSymbol &Symbol = Target.getSymA()->getSymbol();
const MCSymbol &A = Symbol.AliasedSymbol();
if (!Asm.hasSymbolData(A))
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + A.getName() + "' can not be undefined");
const MCSymbolData &A_SD = Asm.getSymbolData(A);
MCSectionData const *SectionData = Fragment->getParent();
// Mark this symbol as requiring an entry in the symbol table.
assert(SectionMap.find(&SectionData->getSection()) != SectionMap.end() &&
"Section must already have been defined in ExecutePostLayoutBinding!");
assert(SymbolMap.find(&A_SD.getSymbol()) != SymbolMap.end() &&
"Symbol must already have been defined in ExecutePostLayoutBinding!");
COFFSection *coff_section = SectionMap[&SectionData->getSection()];
COFFSymbol *coff_symbol = SymbolMap[&A_SD.getSymbol()];
const MCSymbolRefExpr *SymB = Target.getSymB();
bool CrossSection = false;
if (SymB) {
const MCSymbol *B = &SymB->getSymbol();
const MCSymbolData &B_SD = Asm.getSymbolData(*B);
if (!B_SD.getFragment())
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + B->getName() +
"' can not be undefined in a subtraction expression");
if (!A_SD.getFragment())
Asm.getContext().FatalError(
Fixup.getLoc(),
Twine("symbol '") + Symbol.getName() +
"' can not be undefined in a subtraction expression");
CrossSection = &Symbol.getSection() != &B->getSection();
// Offset of the symbol in the section
int64_t a = Layout.getSymbolOffset(&B_SD);
// Ofeset of the relocation in the section
int64_t b = Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
FixedValue = b - a;
// In the case where we have SymbA and SymB, we just need to store the delta
// between the two symbols. Update FixedValue to account for the delta, and
// skip recording the relocation.
if (!CrossSection)
return;
} else {
FixedValue = Target.getConstant();
}
COFFRelocation Reloc;
Reloc.Data.SymbolTableIndex = 0;
Reloc.Data.VirtualAddress = Layout.getFragmentOffset(Fragment);
// Turn relocations for temporary symbols into section relocations.
if (coff_symbol->MCData->getSymbol().isTemporary() || CrossSection) {
Reloc.Symb = coff_symbol->Section->Symbol;
FixedValue += Layout.getFragmentOffset(coff_symbol->MCData->Fragment)
+ coff_symbol->MCData->getOffset();
} else
Reloc.Symb = coff_symbol;
++Reloc.Symb->Relocations;
Reloc.Data.VirtualAddress += Fixup.getOffset();
Reloc.Data.Type = TargetObjectWriter->getRelocType(Target, Fixup,
CrossSection);
// FIXME: Can anyone explain what this does other than adjust for the size
// of the offset?
if ((Header.Machine == COFF::IMAGE_FILE_MACHINE_AMD64 &&
Reloc.Data.Type == COFF::IMAGE_REL_AMD64_REL32) ||
(Header.Machine == COFF::IMAGE_FILE_MACHINE_I386 &&
Reloc.Data.Type == COFF::IMAGE_REL_I386_REL32))
FixedValue += 4;
if (Header.Machine == COFF::IMAGE_FILE_MACHINE_ARMNT) {
switch (Reloc.Data.Type) {
case COFF::IMAGE_REL_ARM_ABSOLUTE:
case COFF::IMAGE_REL_ARM_ADDR32:
case COFF::IMAGE_REL_ARM_ADDR32NB:
case COFF::IMAGE_REL_ARM_TOKEN:
case COFF::IMAGE_REL_ARM_SECTION:
case COFF::IMAGE_REL_ARM_SECREL:
break;
case COFF::IMAGE_REL_ARM_BRANCH11:
case COFF::IMAGE_REL_ARM_BLX11:
// IMAGE_REL_ARM_BRANCH11 and IMAGE_REL_ARM_BLX11 are only used for
// pre-ARMv7, which implicitly rules it out of ARMNT (it would be valid
// for Windows CE).
case COFF::IMAGE_REL_ARM_BRANCH24:
case COFF::IMAGE_REL_ARM_BLX24:
case COFF::IMAGE_REL_ARM_MOV32A:
// IMAGE_REL_ARM_BRANCH24, IMAGE_REL_ARM_BLX24, IMAGE_REL_ARM_MOV32A are
// only used for ARM mode code, which is documented as being unsupported
// by Windows on ARM. Emperical proof indicates that masm is able to
// generate the relocations however the rest of the MSVC toolchain is
// unable to handle it.
llvm_unreachable("unsupported relocation");
break;
case COFF::IMAGE_REL_ARM_MOV32T:
break;
case COFF::IMAGE_REL_ARM_BRANCH20T:
case COFF::IMAGE_REL_ARM_BRANCH24T:
case COFF::IMAGE_REL_ARM_BLX23T:
// IMAGE_REL_BRANCH20T, IMAGE_REL_ARM_BRANCH24T, IMAGE_REL_ARM_BLX23T all
// perform a 4 byte adjustment to the relocation. Relative branches are
// offset by 4 on ARM, however, because there is no RELA relocations, all
// branches are offset by 4.
FixedValue = FixedValue + 4;
break;
}
}
coff_section->Relocations.push_back(Reloc);
}
// assumes IsILP32 is true
static bool isNonILP32reloc(const MCFixup &Fixup,
AArch64MCExpr::VariantKind RefKind,
MCContext &Ctx) {
if ((unsigned)Fixup.getKind() != AArch64::fixup_aarch64_movw)
return false;
switch(RefKind) {
case AArch64MCExpr::VK_ABS_G3:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_UABS_G3));
return true;
case AArch64MCExpr::VK_ABS_G2:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_UABS_G2));
return true;
case AArch64MCExpr::VK_ABS_G2_S:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_SABS_G2));
return true;
case AArch64MCExpr::VK_ABS_G2_NC:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_UABS_G2_NC));
return true;
case AArch64MCExpr::VK_ABS_G1_S:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_SABS_G1));
return true;
case AArch64MCExpr::VK_ABS_G1_NC:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(MOVW_UABS_G1_NC));
return true;
case AArch64MCExpr::VK_DTPREL_G2:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSLD_MOVW_DTPREL_G2));
return true;
case AArch64MCExpr::VK_DTPREL_G1_NC:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSLD_MOVW_DTPREL_G1_NC));
return true;
case AArch64MCExpr::VK_TPREL_G2:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSLE_MOVW_TPREL_G2));
return true;
case AArch64MCExpr::VK_TPREL_G1_NC:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSLE_MOVW_TPREL_G1_NC));
return true;
case AArch64MCExpr::VK_GOTTPREL_G1:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSIE_MOVW_GOTTPREL_G1));
return true;
case AArch64MCExpr::VK_GOTTPREL_G0_NC:
Ctx.reportError(Fixup.getLoc(), BAD_ILP32_MOV(TLSIE_MOVW_GOTTPREL_G0_NC));
return true;
default: return false;
}
return false;
}
void X86MachObjectWriter::RecordX86_64Relocation(
MachObjectWriter *Writer, MCAssembler &Asm, const MCAsmLayout &Layout,
const MCFragment *Fragment, const MCFixup &Fixup, MCValue Target,
uint64_t &FixedValue) {
unsigned IsPCRel = Writer->isFixupKindPCRel(Asm, Fixup.getKind());
unsigned IsRIPRel = isFixupKindRIPRel(Fixup.getKind());
unsigned Log2Size = getFixupKindLog2Size(Fixup.getKind());
// See <reloc.h>.
uint32_t FixupOffset =
Layout.getFragmentOffset(Fragment) + Fixup.getOffset();
uint32_t FixupAddress =
Writer->getFragmentAddress(Fragment, Layout) + Fixup.getOffset();
int64_t Value = 0;
unsigned Index = 0;
unsigned IsExtern = 0;
unsigned Type = 0;
const MCSymbol *RelSymbol = nullptr;
Value = Target.getConstant();
if (IsPCRel) {
// Compensate for the relocation offset, Darwin x86_64 relocations only have
// the addend and appear to have attempted to define it to be the actual
// expression addend without the PCrel bias. However, instructions with data
// following the relocation are not accommodated for (see comment below
// regarding SIGNED{1,2,4}), so it isn't exactly that either.
Value += 1LL << Log2Size;
}
if (Target.isAbsolute()) { // constant
// SymbolNum of 0 indicates the absolute section.
Type = MachO::X86_64_RELOC_UNSIGNED;
// FIXME: I believe this is broken, I don't think the linker can understand
// it. I think it would require a local relocation, but I'm not sure if that
// would work either. The official way to get an absolute PCrel relocation
// is to use an absolute symbol (which we don't support yet).
if (IsPCRel) {
IsExtern = 1;
Type = MachO::X86_64_RELOC_BRANCH;
}
} else if (Target.getSymB()) { // A - B + constant
const MCSymbol *A = &Target.getSymA()->getSymbol();
if (A->isTemporary())
A = &Writer->findAliasedSymbol(*A);
const MCSymbolData &A_SD = Asm.getSymbolData(*A);
const MCSymbol *A_Base = Asm.getAtom(&A_SD);
const MCSymbol *B = &Target.getSymB()->getSymbol();
if (B->isTemporary())
B = &Writer->findAliasedSymbol(*B);
const MCSymbolData &B_SD = Asm.getSymbolData(*B);
const MCSymbol *B_Base = Asm.getAtom(&B_SD);
// Neither symbol can be modified.
if (Target.getSymA()->getKind() != MCSymbolRefExpr::VK_None ||
Target.getSymB()->getKind() != MCSymbolRefExpr::VK_None)
report_fatal_error("unsupported relocation of modified symbol", false);
// We don't support PCrel relocations of differences. Darwin 'as' doesn't
// implement most of these correctly.
if (IsPCRel)
report_fatal_error("unsupported pc-relative relocation of difference",
false);
// The support for the situation where one or both of the symbols would
// require a local relocation is handled just like if the symbols were
// external. This is certainly used in the case of debug sections where the
// section has only temporary symbols and thus the symbols don't have base
// symbols. This is encoded using the section ordinal and non-extern
// relocation entries.
// Darwin 'as' doesn't emit correct relocations for this (it ends up with a
// single SIGNED relocation); reject it for now. Except the case where both
// symbols don't have a base, equal but both NULL.
if (A_Base == B_Base && A_Base)
report_fatal_error("unsupported relocation with identical base", false);
// A subtraction expression where either symbol is undefined is a
// non-relocatable expression.
if (A->isUndefined() || B->isUndefined()) {
StringRef Name = A->isUndefined() ? A->getName() : B->getName();
Asm.getContext().FatalError(Fixup.getLoc(),
"unsupported relocation with subtraction expression, symbol '" +
Name + "' can not be undefined in a subtraction expression");
}
Value +=
Writer->getSymbolAddress(&A_SD, Layout) -
(!A_Base ? 0 : Writer->getSymbolAddress(&A_Base->getData(), Layout));
Value -=
Writer->getSymbolAddress(&B_SD, Layout) -
(!B_Base ? 0 : Writer->getSymbolAddress(&B_Base->getData(), Layout));
if (!A_Base)
Index = A_SD.getFragment()->getParent()->getOrdinal() + 1;
Type = MachO::X86_64_RELOC_UNSIGNED;
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 =
(Index << 0) | (IsPCRel << 24) | (Log2Size << 25) | (Type << 28);
Writer->addRelocation(A_Base, Fragment->getParent(), MRE);
if (B_Base)
RelSymbol = B_Base;
else
Index = B_SD.getFragment()->getParent()->getOrdinal() + 1;
Type = MachO::X86_64_RELOC_SUBTRACTOR;
} else {
const MCSymbol *Symbol = &Target.getSymA()->getSymbol();
if (Symbol->isTemporary() && Value) {
const MCSection &Sec = Symbol->getSection();
if (!Asm.getContext().getAsmInfo()->isSectionAtomizableBySymbols(Sec))
Asm.addLocalUsedInReloc(*Symbol);
}
const MCSymbolData &SD = Asm.getSymbolData(*Symbol);
RelSymbol = Asm.getAtom(&SD);
// Relocations inside debug sections always use local relocations when
// possible. This seems to be done because the debugger doesn't fully
// understand x86_64 relocation entries, and expects to find values that
// have already been fixed up.
if (Symbol->isInSection()) {
const MCSectionMachO &Section = static_cast<const MCSectionMachO&>(
Fragment->getParent()->getSection());
if (Section.hasAttribute(MachO::S_ATTR_DEBUG))
RelSymbol = nullptr;
}
// x86_64 almost always uses external relocations, except when there is no
// symbol to use as a base address (a local symbol with no preceding
// non-local symbol).
if (RelSymbol) {
// Add the local offset, if needed.
if (&RelSymbol->getData() != &SD)
Value += Layout.getSymbolOffset(&SD) -
Layout.getSymbolOffset(&RelSymbol->getData());
} else if (Symbol->isInSection() && !Symbol->isVariable()) {
// The index is the section ordinal (1-based).
Index = SD.getFragment()->getParent()->getOrdinal() + 1;
Value += Writer->getSymbolAddress(&SD, Layout);
if (IsPCRel)
Value -= FixupAddress + (1 << Log2Size);
} else if (Symbol->isVariable()) {
const MCExpr *Value = Symbol->getVariableValue();
int64_t Res;
bool isAbs = Value->EvaluateAsAbsolute(Res, Layout,
Writer->getSectionAddressMap());
if (isAbs) {
FixedValue = Res;
return;
} else {
report_fatal_error("unsupported relocation of variable '" +
Symbol->getName() + "'", false);
}
} else {
report_fatal_error("unsupported relocation of undefined symbol '" +
Symbol->getName() + "'", false);
}
MCSymbolRefExpr::VariantKind Modifier = Target.getSymA()->getKind();
if (IsPCRel) {
if (IsRIPRel) {
if (Modifier == MCSymbolRefExpr::VK_GOTPCREL) {
// x86_64 distinguishes movq foo@GOTPCREL so that the linker can
// rewrite the movq to an leaq at link time if the symbol ends up in
// the same linkage unit.
if (unsigned(Fixup.getKind()) == X86::reloc_riprel_4byte_movq_load)
Type = MachO::X86_64_RELOC_GOT_LOAD;
else
Type = MachO::X86_64_RELOC_GOT;
} else if (Modifier == MCSymbolRefExpr::VK_TLVP) {
Type = MachO::X86_64_RELOC_TLV;
} else if (Modifier != MCSymbolRefExpr::VK_None) {
report_fatal_error("unsupported symbol modifier in relocation",
false);
} else {
Type = MachO::X86_64_RELOC_SIGNED;
// The Darwin x86_64 relocation format has a problem where it cannot
// encode an address (L<foo> + <constant>) which is outside the atom
// containing L<foo>. Generally, this shouldn't occur but it does
// happen when we have a RIPrel instruction with data following the
// relocation entry (e.g., movb $012, L0(%rip)). Even with the PCrel
// adjustment Darwin x86_64 uses, the offset is still negative and the
// linker has no way to recognize this.
//
// To work around this, Darwin uses several special relocation types
// to indicate the offsets. However, the specification or
// implementation of these seems to also be incomplete; they should
// adjust the addend as well based on the actual encoded instruction
// (the additional bias), but instead appear to just look at the final
// offset.
switch (-(Target.getConstant() + (1LL << Log2Size))) {
case 1: Type = MachO::X86_64_RELOC_SIGNED_1; break;
case 2: Type = MachO::X86_64_RELOC_SIGNED_2; break;
case 4: Type = MachO::X86_64_RELOC_SIGNED_4; break;
}
}
} else {
if (Modifier != MCSymbolRefExpr::VK_None)
report_fatal_error("unsupported symbol modifier in branch "
"relocation", false);
Type = MachO::X86_64_RELOC_BRANCH;
}
} else {
if (Modifier == MCSymbolRefExpr::VK_GOT) {
Type = MachO::X86_64_RELOC_GOT;
} else if (Modifier == MCSymbolRefExpr::VK_GOTPCREL) {
// GOTPCREL is allowed as a modifier on non-PCrel instructions, in which
// case all we do is set the PCrel bit in the relocation entry; this is
// used with exception handling, for example. The source is required to
// include any necessary offset directly.
Type = MachO::X86_64_RELOC_GOT;
IsPCRel = 1;
} else if (Modifier == MCSymbolRefExpr::VK_TLVP) {
report_fatal_error("TLVP symbol modifier should have been rip-rel",
false);
} else if (Modifier != MCSymbolRefExpr::VK_None)
report_fatal_error("unsupported symbol modifier in relocation", false);
else {
Type = MachO::X86_64_RELOC_UNSIGNED;
unsigned Kind = Fixup.getKind();
if (Kind == X86::reloc_signed_4byte)
report_fatal_error("32-bit absolute addressing is not supported in "
"64-bit mode", false);
}
}
}
// x86_64 always writes custom values into the fixups.
FixedValue = Value;
// struct relocation_info (8 bytes)
MachO::any_relocation_info MRE;
MRE.r_word0 = FixupOffset;
MRE.r_word1 = (Index << 0) | (IsPCRel << 24) | (Log2Size << 25) |
(IsExtern << 27) | (Type << 28);
Writer->addRelocation(RelSymbol, Fragment->getParent(), MRE);
}
static uint64_t adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
MCContext *Ctx) {
unsigned Kind = Fixup.getKind();
int64_t SignedValue = static_cast<int64_t>(Value);
switch (Kind) {
default:
llvm_unreachable("Unknown fixup kind!");
case AArch64::fixup_aarch64_pcrel_adr_imm21:
if (Ctx && (SignedValue > 2097151 || SignedValue < -2097152))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
return AdrImmBits(Value & 0x1fffffULL);
case AArch64::fixup_aarch64_pcrel_adrp_imm21:
return AdrImmBits((Value & 0x1fffff000ULL) >> 12);
case AArch64::fixup_aarch64_ldr_pcrel_imm19:
case AArch64::fixup_aarch64_pcrel_branch19:
// Signed 21-bit immediate
if (SignedValue > 2097151 || SignedValue < -2097152)
if (Ctx) Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
if (Ctx && (Value & 0x3))
Ctx->reportError(Fixup.getLoc(), "fixup not sufficiently aligned");
// Low two bits are not encoded.
return (Value >> 2) & 0x7ffff;
case AArch64::fixup_aarch64_add_imm12:
case AArch64::fixup_aarch64_ldst_imm12_scale1:
// Unsigned 12-bit immediate
if (Ctx && Value >= 0x1000)
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
return Value;
case AArch64::fixup_aarch64_ldst_imm12_scale2:
// Unsigned 12-bit immediate which gets multiplied by 2
if (Ctx && (Value >= 0x2000))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
if (Ctx && (Value & 0x1))
Ctx->reportError(Fixup.getLoc(), "fixup must be 2-byte aligned");
return Value >> 1;
case AArch64::fixup_aarch64_ldst_imm12_scale4:
// Unsigned 12-bit immediate which gets multiplied by 4
if (Ctx && (Value >= 0x4000))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
if (Ctx && (Value & 0x3))
Ctx->reportError(Fixup.getLoc(), "fixup must be 4-byte aligned");
return Value >> 2;
case AArch64::fixup_aarch64_ldst_imm12_scale8:
// Unsigned 12-bit immediate which gets multiplied by 8
if (Ctx && (Value >= 0x8000))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
if (Ctx && (Value & 0x7))
Ctx->reportError(Fixup.getLoc(), "fixup must be 8-byte aligned");
return Value >> 3;
case AArch64::fixup_aarch64_ldst_imm12_scale16:
// Unsigned 12-bit immediate which gets multiplied by 16
if (Ctx && (Value >= 0x10000))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
if (Ctx && (Value & 0xf))
Ctx->reportError(Fixup.getLoc(), "fixup must be 16-byte aligned");
return Value >> 4;
case AArch64::fixup_aarch64_movw:
if (Ctx)
Ctx->reportError(Fixup.getLoc(),
"no resolvable MOVZ/MOVK fixups supported yet");
return Value;
case AArch64::fixup_aarch64_pcrel_branch14:
// Signed 16-bit immediate
if (Ctx && (SignedValue > 32767 || SignedValue < -32768))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
// Low two bits are not encoded (4-byte alignment assumed).
if (Ctx && (Value & 0x3))
Ctx->reportError(Fixup.getLoc(), "fixup not sufficiently aligned");
return (Value >> 2) & 0x3fff;
case AArch64::fixup_aarch64_pcrel_branch26:
case AArch64::fixup_aarch64_pcrel_call26:
// Signed 28-bit immediate
if (Ctx && (SignedValue > 134217727 || SignedValue < -134217728))
Ctx->reportError(Fixup.getLoc(), "fixup value out of range");
// Low two bits are not encoded (4-byte alignment assumed).
if (Ctx && (Value & 0x3))
Ctx->reportError(Fixup.getLoc(), "fixup not sufficiently aligned");
return (Value >> 2) & 0x3ffffff;
case FK_Data_1:
case FK_Data_2:
case FK_Data_4:
case FK_Data_8:
return Value;
}
}
