//
//===----------------------------------------------------------------------===//
-#include "MCTargetDesc/X86FixupKinds.h"
#include "MCTargetDesc/X86MCTargetDesc.h"
-#include "llvm/MC/MCAssembler.h"
+#include "MCTargetDesc/X86FixupKinds.h"
+#include "llvm/ADT/Twine.h"
#include "llvm/MC/MCAsmLayout.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCMachObjectWriter.h"
#include "llvm/MC/MCSectionMachO.h"
#include "llvm/MC/MCValue.h"
-#include "llvm/ADT/Twine.h"
#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Object/MachOFormat.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/MachO.h"
using namespace llvm;
-using namespace llvm::object;
namespace {
class X86MachObjectWriter : public MCMachObjectTargetWriter {
- void RecordScatteredRelocation(MachObjectWriter *Writer,
+ bool RecordScatteredRelocation(MachObjectWriter *Writer,
const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
void RecordRelocation(MachObjectWriter *Writer,
const MCAssembler &Asm, const MCAsmLayout &Layout,
const MCFragment *Fragment, const MCFixup &Fixup,
- MCValue Target, uint64_t &FixedValue) {
+ MCValue Target, uint64_t &FixedValue) override {
if (Writer->is64Bit())
RecordX86_64Relocation(Writer, Asm, Layout, Fragment, Fixup, Target,
FixedValue);
if (Target.isAbsolute()) { // constant
// SymbolNum of 0 indicates the absolute section.
- Type = macho::RIT_X86_64_Unsigned;
+ Type = MachO::X86_64_RELOC_UNSIGNED;
Index = 0;
// FIXME: I believe this is broken, I don't think the linker can understand
// is to use an absolute symbol (which we don't support yet).
if (IsPCRel) {
IsExtern = 1;
- Type = macho::RIT_X86_64_Branch;
+ Type = MachO::X86_64_RELOC_BRANCH;
}
} else if (Target.getSymB()) { // A - B + constant
const MCSymbol *A = &Target.getSymA()->getSymbol();
- MCSymbolData &A_SD = Asm.getSymbolData(*A);
+ if (A->isTemporary())
+ A = &A->AliasedSymbol();
+ const MCSymbolData &A_SD = Asm.getSymbolData(*A);
const MCSymbolData *A_Base = Asm.getAtom(&A_SD);
const MCSymbol *B = &Target.getSymB()->getSymbol();
- MCSymbolData &B_SD = Asm.getSymbolData(*B);
+ if (B->isTemporary())
+ B = &B->AliasedSymbol();
+ const MCSymbolData &B_SD = Asm.getSymbolData(*B);
const MCSymbolData *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");
+ 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");
+ 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
// 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");
+ 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 == NULL ? 0 : Writer->getSymbolAddress(A_Base, Layout));
+ (!A_Base ? 0 : Writer->getSymbolAddress(A_Base, Layout));
Value -= Writer->getSymbolAddress(&B_SD, Layout) -
- (B_Base == NULL ? 0 : Writer->getSymbolAddress(B_Base, Layout));
+ (!B_Base ? 0 : Writer->getSymbolAddress(B_Base, Layout));
if (A_Base) {
Index = A_Base->getIndex();
Index = A_SD.getFragment()->getParent()->getOrdinal() + 1;
IsExtern = 0;
}
- Type = macho::RIT_X86_64_Unsigned;
-
- macho::RelocationEntry MRE;
- MRE.Word0 = FixupOffset;
- MRE.Word1 = ((Index << 0) |
- (IsPCRel << 24) |
- (Log2Size << 25) |
- (IsExtern << 27) |
- (Type << 28));
+ Type = MachO::X86_64_RELOC_UNSIGNED;
+
+ MachO::any_relocation_info MRE;
+ MRE.r_word0 = FixupOffset;
+ MRE.r_word1 = ((Index << 0) |
+ (IsPCRel << 24) |
+ (Log2Size << 25) |
+ (IsExtern << 27) |
+ (Type << 28));
Writer->addRelocation(Fragment->getParent(), MRE);
if (B_Base) {
Index = B_SD.getFragment()->getParent()->getOrdinal() + 1;
IsExtern = 0;
}
- Type = macho::RIT_X86_64_Subtractor;
+ Type = MachO::X86_64_RELOC_SUBTRACTOR;
} else {
const MCSymbol *Symbol = &Target.getSymA()->getSymbol();
- MCSymbolData &SD = Asm.getSymbolData(*Symbol);
+ const MCSymbolData &SD = Asm.getSymbolData(*Symbol);
const MCSymbolData *Base = Asm.getAtom(&SD);
// Relocations inside debug sections always use local relocations when
if (Symbol->isInSection()) {
const MCSectionMachO &Section = static_cast<const MCSectionMachO&>(
Fragment->getParent()->getSection());
- if (Section.hasAttribute(MCSectionMachO::S_ATTR_DEBUG))
- Base = 0;
+ if (Section.hasAttribute(MachO::S_ATTR_DEBUG))
+ Base = nullptr;
}
// x86_64 almost always uses external relocations, except when there is no
return;
} else {
report_fatal_error("unsupported relocation of variable '" +
- Symbol->getName() + "'");
+ Symbol->getName() + "'", false);
}
} else {
report_fatal_error("unsupported relocation of undefined symbol '" +
- Symbol->getName() + "'");
+ Symbol->getName() + "'", false);
}
MCSymbolRefExpr::VariantKind Modifier = Target.getSymA()->getKind();
// 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::RIT_X86_64_GOTLoad;
+ Type = MachO::X86_64_RELOC_GOT_LOAD;
else
- Type = macho::RIT_X86_64_GOT;
+ Type = MachO::X86_64_RELOC_GOT;
} else if (Modifier == MCSymbolRefExpr::VK_TLVP) {
- Type = macho::RIT_X86_64_TLV;
+ Type = MachO::X86_64_RELOC_TLV;
} else if (Modifier != MCSymbolRefExpr::VK_None) {
- report_fatal_error("unsupported symbol modifier in relocation");
+ report_fatal_error("unsupported symbol modifier in relocation",
+ false);
} else {
- Type = macho::RIT_X86_64_Signed;
+ 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
// (the additional bias), but instead appear to just look at the final
// offset.
switch (-(Target.getConstant() + (1LL << Log2Size))) {
- case 1: Type = macho::RIT_X86_64_Signed1; break;
- case 2: Type = macho::RIT_X86_64_Signed2; break;
- case 4: Type = macho::RIT_X86_64_Signed4; break;
+ 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");
+ "relocation", false);
- Type = macho::RIT_X86_64_Branch;
+ Type = MachO::X86_64_RELOC_BRANCH;
}
} else {
if (Modifier == MCSymbolRefExpr::VK_GOT) {
- Type = macho::RIT_X86_64_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::RIT_X86_64_GOT;
+ 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");
+ 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");
- else
- Type = macho::RIT_X86_64_Unsigned;
+ 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);
+ }
}
}
FixedValue = Value;
// struct relocation_info (8 bytes)
- macho::RelocationEntry MRE;
- MRE.Word0 = FixupOffset;
- MRE.Word1 = ((Index << 0) |
- (IsPCRel << 24) |
- (Log2Size << 25) |
- (IsExtern << 27) |
- (Type << 28));
+ MachO::any_relocation_info MRE;
+ MRE.r_word0 = FixupOffset;
+ MRE.r_word1 = ((Index << 0) |
+ (IsPCRel << 24) |
+ (Log2Size << 25) |
+ (IsExtern << 27) |
+ (Type << 28));
Writer->addRelocation(Fragment->getParent(), MRE);
}
-void X86MachObjectWriter::RecordScatteredRelocation(MachObjectWriter *Writer,
+bool X86MachObjectWriter::RecordScatteredRelocation(MachObjectWriter *Writer,
const MCAssembler &Asm,
const MCAsmLayout &Layout,
const MCFragment *Fragment,
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::RIT_Vanilla;
+ unsigned Type = MachO::GENERIC_RELOC_VANILLA;
// See <reloc.h>.
const MCSymbol *A = &Target.getSymA()->getSymbol();
- MCSymbolData *A_SD = &Asm.getSymbolData(*A);
+ 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");
+ "' 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());
uint32_t Value2 = 0;
if (const MCSymbolRefExpr *B = Target.getSymB()) {
- MCSymbolData *B_SD = &Asm.getSymbolData(B->getSymbol());
+ 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");
+ "' 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::RIT_Difference :
- (unsigned)macho::RIT_Generic_LocalDifference;
+ 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::RIT_Difference ||
- Type == macho::RIT_Generic_LocalDifference) {
- macho::RelocationEntry MRE;
- MRE.Word0 = ((0 << 0) |
- (macho::RIT_Pair << 24) |
- (Log2Size << 28) |
- (IsPCRel << 30) |
- macho::RF_Scattered);
- MRE.Word1 = Value2;
+ 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(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::RelocationEntry MRE;
- MRE.Word0 = ((FixupOffset << 0) |
- (Type << 24) |
- (Log2Size << 28) |
- (IsPCRel << 30) |
- macho::RF_Scattered);
- MRE.Word1 = Value;
+ 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(Fragment->getParent(), MRE);
+ return true;
}
void X86MachObjectWriter::RecordTLVPRelocation(MachObjectWriter *Writer,
unsigned IsPCRel = 0;
// Get the symbol data.
- MCSymbolData *SD_A = &Asm.getSymbolData(Target.getSymA()->getSymbol());
+ const MCSymbolData *SD_A = &Asm.getSymbolData(Target.getSymA()->getSymbol());
unsigned Index = SD_A->getIndex();
// We're only going to have a second symbol in pic mode and it'll be a
// If this is a subtraction then we're pcrel.
uint32_t FixupAddress =
Writer->getFragmentAddress(Fragment, Layout) + Fixup.getOffset();
- MCSymbolData *SD_B = &Asm.getSymbolData(Target.getSymB()->getSymbol());
+ const MCSymbolData *SD_B =
+ &Asm.getSymbolData(Target.getSymB()->getSymbol());
IsPCRel = 1;
FixedValue = (FixupAddress - Writer->getSymbolAddress(SD_B, Layout) +
Target.getConstant());
}
// struct relocation_info (8 bytes)
- macho::RelocationEntry MRE;
- MRE.Word0 = Value;
- MRE.Word1 = ((Index << 0) |
- (IsPCRel << 24) |
- (Log2Size << 25) |
- (1 << 27) | // Extern
- (macho::RIT_Generic_TLV << 28)); // Type
+ MachO::any_relocation_info MRE;
+ MRE.r_word0 = Value;
+ MRE.r_word1 = ((Index << 0) |
+ (IsPCRel << 24) |
+ (Log2Size << 25) |
+ (1 << 27) | // r_extern
+ (MachO::GENERIC_RELOC_TLV << 28)); // r_type
Writer->addRelocation(Fragment->getParent(), MRE);
}
// If this is a difference or a defined symbol plus an offset, then we need a
// scattered relocation entry. Differences always require scattered
// relocations.
- if (Target.getSymB())
- return RecordScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
- Target, Log2Size, FixedValue);
+ if (Target.getSymB()) {
+ RecordScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
+ Target, Log2Size, FixedValue);
+ return;
+ }
// Get the symbol data, if any.
- MCSymbolData *SD = 0;
+ const MCSymbolData *SD = nullptr;
if (Target.getSymA())
SD = &Asm.getSymbolData(Target.getSymA()->getSymbol());
uint32_t Offset = Target.getConstant();
if (IsPCRel)
Offset += 1 << Log2Size;
- if (Offset && SD && !Writer->doesSymbolRequireExternRelocation(SD))
- return RecordScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
- Target, Log2Size, FixedValue);
+ // Try to record the scattered relocation if needed. Fall back to non
+ // scattered if necessary (see comments in RecordScatteredRelocation()
+ // for details).
+ if (Offset && SD && !Writer->doesSymbolRequireExternRelocation(SD) &&
+ RecordScatteredRelocation(Writer, Asm, Layout, Fragment, Fixup,
+ Target, Log2Size, FixedValue))
+ return;
// See <reloc.h>.
uint32_t FixupOffset = Layout.getFragmentOffset(Fragment)+Fixup.getOffset();
//
// FIXME: Currently, these are never generated (see code below). I cannot
// find a case where they are actually emitted.
- Type = macho::RIT_Vanilla;
+ Type = MachO::GENERIC_RELOC_VANILLA;
} else {
// Resolve constant variables.
if (SD->getSymbol().isVariable()) {
// For external relocations, make sure to offset the fixup value to
// compensate for the addend of the symbol address, if it was
// undefined. This occurs with weak definitions, for example.
- if (!SD->Symbol->isUndefined())
+ if (!SD->getSymbol().isUndefined())
FixedValue -= Layout.getSymbolOffset(SD);
} else {
// The index is the section ordinal (1-based).
if (IsPCRel)
FixedValue -= Writer->getSectionAddress(Fragment->getParent());
- Type = macho::RIT_Vanilla;
+ Type = MachO::GENERIC_RELOC_VANILLA;
}
// struct relocation_info (8 bytes)
- macho::RelocationEntry MRE;
- MRE.Word0 = FixupOffset;
- MRE.Word1 = ((Index << 0) |
- (IsPCRel << 24) |
- (Log2Size << 25) |
- (IsExtern << 27) |
- (Type << 28));
+ MachO::any_relocation_info MRE;
+ MRE.r_word0 = FixupOffset;
+ MRE.r_word1 = ((Index << 0) |
+ (IsPCRel << 24) |
+ (Log2Size << 25) |
+ (IsExtern << 27) |
+ (Type << 28));
Writer->addRelocation(Fragment->getParent(), MRE);
}
projects / oota-llvm.git / blobdiff