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-rw-r--r--lib/ExecutionEngine/JITLink/MachOAtomGraphBuilder.cpp411
1 files changed, 0 insertions, 411 deletions
diff --git a/lib/ExecutionEngine/JITLink/MachOAtomGraphBuilder.cpp b/lib/ExecutionEngine/JITLink/MachOAtomGraphBuilder.cpp
deleted file mode 100644
index 1501c7ad0bc5..000000000000
--- a/lib/ExecutionEngine/JITLink/MachOAtomGraphBuilder.cpp
+++ /dev/null
@@ -1,411 +0,0 @@
-//=--------- MachOAtomGraphBuilder.cpp - MachO AtomGraph builder ----------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// Generic MachO AtomGraph buliding code.
-//
-//===----------------------------------------------------------------------===//
-
-#include "MachOAtomGraphBuilder.h"
-
-#define DEBUG_TYPE "jitlink"
-
-namespace llvm {
-namespace jitlink {
-
-MachOAtomGraphBuilder::~MachOAtomGraphBuilder() {}
-
-Expected<std::unique_ptr<AtomGraph>> MachOAtomGraphBuilder::buildGraph() {
- if (auto Err = parseSections())
- return std::move(Err);
-
- if (auto Err = addAtoms())
- return std::move(Err);
-
- if (auto Err = addRelocations())
- return std::move(Err);
-
- return std::move(G);
-}
-
-MachOAtomGraphBuilder::MachOAtomGraphBuilder(const object::MachOObjectFile &Obj)
- : Obj(Obj),
- G(llvm::make_unique<AtomGraph>(Obj.getFileName(), getPointerSize(Obj),
- getEndianness(Obj))) {}
-
-void MachOAtomGraphBuilder::addCustomAtomizer(StringRef SectionName,
- CustomAtomizeFunction Atomizer) {
- assert(!CustomAtomizeFunctions.count(SectionName) &&
- "Custom atomizer for this section already exists");
- CustomAtomizeFunctions[SectionName] = std::move(Atomizer);
-}
-
-bool MachOAtomGraphBuilder::areLayoutLocked(const Atom &A, const Atom &B) {
- // If these atoms are the same then they're trivially "locked".
- if (&A == &B)
- return true;
-
- // If A and B are different, check whether either is undefined. (in which
- // case they are not locked).
- if (!A.isDefined() || !B.isDefined())
- return false;
-
- // A and B are different, but they're both defined atoms. We need to check
- // whether they're part of the same alt_entry chain.
- auto &DA = static_cast<const DefinedAtom &>(A);
- auto &DB = static_cast<const DefinedAtom &>(B);
-
- auto AStartItr = AltEntryStarts.find(&DA);
- if (AStartItr == AltEntryStarts.end()) // If A is not in a chain bail out.
- return false;
-
- auto BStartItr = AltEntryStarts.find(&DB);
- if (BStartItr == AltEntryStarts.end()) // If B is not in a chain bail out.
- return false;
-
- // A and B are layout locked if they're in the same chain.
- return AStartItr->second == BStartItr->second;
-}
-
-unsigned
-MachOAtomGraphBuilder::getPointerSize(const object::MachOObjectFile &Obj) {
- return Obj.is64Bit() ? 8 : 4;
-}
-
-support::endianness
-MachOAtomGraphBuilder::getEndianness(const object::MachOObjectFile &Obj) {
- return Obj.isLittleEndian() ? support::little : support::big;
-}
-
-MachOAtomGraphBuilder::MachOSection &MachOAtomGraphBuilder::getCommonSection() {
- if (!CommonSymbolsSection) {
- auto Prot = static_cast<sys::Memory::ProtectionFlags>(
- sys::Memory::MF_READ | sys::Memory::MF_WRITE);
- auto &GenericSection = G->createSection("<common>", 1, Prot, true);
- CommonSymbolsSection = MachOSection(GenericSection);
- }
- return *CommonSymbolsSection;
-}
-
-Error MachOAtomGraphBuilder::parseSections() {
- for (auto &SecRef : Obj.sections()) {
- assert((SecRef.getAlignment() <= std::numeric_limits<uint32_t>::max()) &&
- "Section alignment does not fit in 32 bits");
-
- StringRef Name;
- if (auto EC = SecRef.getName(Name))
- return errorCodeToError(EC);
-
- unsigned SectionIndex = SecRef.getIndex() + 1;
-
- uint32_t Align = SecRef.getAlignment();
- if (!isPowerOf2_32(Align))
- return make_error<JITLinkError>("Section " + Name +
- " has non-power-of-2 "
- "alignment");
-
- // FIXME: Get real section permissions
- // How, exactly, on MachO?
- sys::Memory::ProtectionFlags Prot;
- if (SecRef.isText())
- Prot = static_cast<sys::Memory::ProtectionFlags>(sys::Memory::MF_READ |
- sys::Memory::MF_EXEC);
- else
- Prot = static_cast<sys::Memory::ProtectionFlags>(sys::Memory::MF_READ |
- sys::Memory::MF_WRITE);
-
- auto &GenericSection = G->createSection(Name, Align, Prot, SecRef.isBSS());
-
- LLVM_DEBUG({
- dbgs() << "Adding section " << Name << ": "
- << format("0x%016" PRIx64, SecRef.getAddress())
- << ", align: " << SecRef.getAlignment() << "\n";
- });
-
- assert(!Sections.count(SectionIndex) && "Section index already in use");
-
- auto &MachOSec =
- Sections
- .try_emplace(SectionIndex, GenericSection, SecRef.getAddress(),
- SecRef.getAlignment())
- .first->second;
-
- if (!SecRef.isVirtual()) {
- // If this section has content then record it.
- Expected<StringRef> Content = SecRef.getContents();
- if (!Content)
- return Content.takeError();
- if (Content->size() != SecRef.getSize())
- return make_error<JITLinkError>("Section content size does not match "
- "declared size for " +
- Name);
- MachOSec.setContent(*Content);
- } else {
- // If this is a zero-fill section then just record the size.
- MachOSec.setZeroFill(SecRef.getSize());
- }
-
- uint32_t SectionFlags =
- Obj.is64Bit() ? Obj.getSection64(SecRef.getRawDataRefImpl()).flags
- : Obj.getSection(SecRef.getRawDataRefImpl()).flags;
-
- MachOSec.setNoDeadStrip(SectionFlags & MachO::S_ATTR_NO_DEAD_STRIP);
- }
-
- return Error::success();
-}
-
-// Adds atoms with identified start addresses (but not lengths) for all named
-// atoms.
-// Also, for every section that contains named atoms, but does not have an
-// atom at offset zero of that section, constructs an anonymous atom covering
-// that range.
-Error MachOAtomGraphBuilder::addNonCustomAtoms() {
- using AddrToAtomMap = std::map<JITTargetAddress, DefinedAtom *>;
- DenseMap<MachOSection *, AddrToAtomMap> SecToAtoms;
-
- DenseMap<MachOSection *, unsigned> FirstOrdinal;
- std::vector<DefinedAtom *> AltEntryAtoms;
-
- DenseSet<StringRef> ProcessedSymbols; // Used to check for duplicate defs.
-
- for (auto SymI = Obj.symbol_begin(), SymE = Obj.symbol_end(); SymI != SymE;
- ++SymI) {
- object::SymbolRef Sym(SymI->getRawDataRefImpl(), &Obj);
-
- auto Name = Sym.getName();
- if (!Name)
- return Name.takeError();
-
- // Bail out on duplicate definitions: There should never be more than one
- // definition for a symbol in a given object file.
- if (ProcessedSymbols.count(*Name))
- return make_error<JITLinkError>("Duplicate definition within object: " +
- *Name);
- else
- ProcessedSymbols.insert(*Name);
-
- auto Addr = Sym.getAddress();
- if (!Addr)
- return Addr.takeError();
-
- auto SymType = Sym.getType();
- if (!SymType)
- return SymType.takeError();
-
- auto Flags = Sym.getFlags();
-
- if (Flags & object::SymbolRef::SF_Undefined) {
- LLVM_DEBUG(dbgs() << "Adding undef atom \"" << *Name << "\"\n");
- G->addExternalAtom(*Name);
- continue;
- } else if (Flags & object::SymbolRef::SF_Absolute) {
- LLVM_DEBUG(dbgs() << "Adding absolute \"" << *Name << "\" addr: "
- << format("0x%016" PRIx64, *Addr) << "\n");
- auto &A = G->addAbsoluteAtom(*Name, *Addr);
- A.setGlobal(Flags & object::SymbolRef::SF_Global);
- A.setExported(Flags & object::SymbolRef::SF_Exported);
- A.setWeak(Flags & object::SymbolRef::SF_Weak);
- continue;
- } else if (Flags & object::SymbolRef::SF_Common) {
- LLVM_DEBUG({
- dbgs() << "Adding common \"" << *Name
- << "\" addr: " << format("0x%016" PRIx64, *Addr) << "\n";
- });
- auto &A =
- G->addCommonAtom(getCommonSection().getGenericSection(), *Name, *Addr,
- std::max(Sym.getAlignment(), 1U),
- Obj.getCommonSymbolSize(Sym.getRawDataRefImpl()));
- A.setGlobal(Flags & object::SymbolRef::SF_Global);
- A.setExported(Flags & object::SymbolRef::SF_Exported);
- continue;
- }
-
- LLVM_DEBUG(dbgs() << "Adding defined atom \"" << *Name << "\"\n");
-
- // This atom is neither undefined nor absolute, so it must be defined in
- // this object. Get its section index.
- auto SecItr = Sym.getSection();
- if (!SecItr)
- return SecItr.takeError();
-
- uint64_t SectionIndex = (*SecItr)->getIndex() + 1;
-
- LLVM_DEBUG(dbgs() << " to section index " << SectionIndex << "\n");
-
- auto SecByIndexItr = Sections.find(SectionIndex);
- if (SecByIndexItr == Sections.end())
- return make_error<JITLinkError>("Unrecognized section index in macho");
-
- auto &Sec = SecByIndexItr->second;
-
- auto &DA = G->addDefinedAtom(Sec.getGenericSection(), *Name, *Addr,
- std::max(Sym.getAlignment(), 1U));
-
- DA.setGlobal(Flags & object::SymbolRef::SF_Global);
- DA.setExported(Flags & object::SymbolRef::SF_Exported);
- DA.setWeak(Flags & object::SymbolRef::SF_Weak);
-
- DA.setCallable(*SymType & object::SymbolRef::ST_Function);
-
- // Check NDesc flags.
- {
- uint16_t NDesc = 0;
- if (Obj.is64Bit())
- NDesc = Obj.getSymbol64TableEntry(SymI->getRawDataRefImpl()).n_desc;
- else
- NDesc = Obj.getSymbolTableEntry(SymI->getRawDataRefImpl()).n_desc;
-
- // Record atom for alt-entry post-processing (where the layout-next
- // constraints will be added).
- if (NDesc & MachO::N_ALT_ENTRY)
- AltEntryAtoms.push_back(&DA);
-
- // If this atom has a no-dead-strip attr attached then mark it live.
- if (NDesc & MachO::N_NO_DEAD_STRIP)
- DA.setLive(true);
- }
-
- LLVM_DEBUG({
- dbgs() << " Added " << *Name
- << " addr: " << format("0x%016" PRIx64, *Addr)
- << ", align: " << DA.getAlignment()
- << ", section: " << Sec.getGenericSection().getName() << "\n";
- });
-
- auto &SecAtoms = SecToAtoms[&Sec];
- SecAtoms[DA.getAddress() - Sec.getAddress()] = &DA;
- }
-
- // Add anonymous atoms.
- for (auto &KV : Sections) {
- auto &S = KV.second;
-
- // Skip empty sections.
- if (S.empty())
- continue;
-
- // Skip sections with custom handling.
- if (CustomAtomizeFunctions.count(S.getName()))
- continue;
-
- auto SAI = SecToAtoms.find(&S);
-
- // If S is not in the SecToAtoms map then it contained no named atom. Add
- // one anonymous atom to cover the whole section.
- if (SAI == SecToAtoms.end()) {
- SecToAtoms[&S][0] = &G->addAnonymousAtom(
- S.getGenericSection(), S.getAddress(), S.getAlignment());
- continue;
- }
-
- // Otherwise, check whether this section had an atom covering offset zero.
- // If not, add one.
- auto &SecAtoms = SAI->second;
- if (!SecAtoms.count(0))
- SecAtoms[0] = &G->addAnonymousAtom(S.getGenericSection(), S.getAddress(),
- S.getAlignment());
- }
-
- LLVM_DEBUG(dbgs() << "MachOGraphBuilder setting atom content\n");
-
- // Set atom contents and any section-based flags.
- for (auto &KV : SecToAtoms) {
- auto &S = *KV.first;
- auto &SecAtoms = KV.second;
-
- // Iterate the atoms in reverse order and set up their contents.
- JITTargetAddress LastAtomAddr = S.getSize();
- for (auto I = SecAtoms.rbegin(), E = SecAtoms.rend(); I != E; ++I) {
- auto Offset = I->first;
- auto &A = *I->second;
- LLVM_DEBUG({
- dbgs() << " " << A << " to [ " << S.getAddress() + Offset << " .. "
- << S.getAddress() + LastAtomAddr << " ]\n";
- });
-
- if (S.isZeroFill())
- A.setZeroFill(LastAtomAddr - Offset);
- else
- A.setContent(S.getContent().substr(Offset, LastAtomAddr - Offset));
-
- // If the section has no-dead-strip set then mark the atom as live.
- if (S.isNoDeadStrip())
- A.setLive(true);
-
- LastAtomAddr = Offset;
- }
- }
-
- LLVM_DEBUG(dbgs() << "Adding alt-entry starts\n");
-
- // Sort alt-entry atoms by address in ascending order.
- llvm::sort(AltEntryAtoms.begin(), AltEntryAtoms.end(),
- [](const DefinedAtom *LHS, const DefinedAtom *RHS) {
- return LHS->getAddress() < RHS->getAddress();
- });
-
- // Process alt-entry atoms in address order to build the table of alt-entry
- // atoms to alt-entry chain starts.
- for (auto *DA : AltEntryAtoms) {
- assert(!AltEntryStarts.count(DA) && "Duplicate entry in AltEntryStarts");
-
- // DA is an alt-entry atom. Look for the predecessor atom that it is locked
- // to, bailing out if we do not find one.
- auto AltEntryPred = G->findAtomByAddress(DA->getAddress() - 1);
- if (!AltEntryPred)
- return AltEntryPred.takeError();
-
- // Add a LayoutNext edge from the predecessor to this atom.
- AltEntryPred->setLayoutNext(*DA);
-
- // Check to see whether the predecessor itself is an alt-entry atom.
- auto AltEntryStartItr = AltEntryStarts.find(&*AltEntryPred);
- if (AltEntryStartItr != AltEntryStarts.end()) {
- // If the predecessor was an alt-entry atom then re-use its value.
- LLVM_DEBUG({
- dbgs() << " " << *DA << " -> " << *AltEntryStartItr->second
- << " (based on existing entry for " << *AltEntryPred << ")\n";
- });
- AltEntryStarts[DA] = AltEntryStartItr->second;
- } else {
- // If the predecessor does not have an entry then add an entry for this
- // atom (i.e. the alt_entry atom) and a self-reference entry for the
- /// predecessory atom that is the start of this chain.
- LLVM_DEBUG({
- dbgs() << " " << *AltEntryPred << " -> " << *AltEntryPred << "\n"
- << " " << *DA << " -> " << *AltEntryPred << "\n";
- });
- AltEntryStarts[&*AltEntryPred] = &*AltEntryPred;
- AltEntryStarts[DA] = &*AltEntryPred;
- }
- }
-
- return Error::success();
-}
-
-Error MachOAtomGraphBuilder::addAtoms() {
- // Add all named atoms.
- if (auto Err = addNonCustomAtoms())
- return Err;
-
- // Process special sections.
- for (auto &KV : Sections) {
- auto &S = KV.second;
- auto HI = CustomAtomizeFunctions.find(S.getGenericSection().getName());
- if (HI != CustomAtomizeFunctions.end()) {
- auto &Atomize = HI->second;
- if (auto Err = Atomize(S))
- return Err;
- }
- }
-
- return Error::success();
-}
-
-} // end namespace jitlink
-} // end namespace llvm
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