[MCJIT] Add a 'decodeAddend' method to RuntimeDyldMachO and teach
[oota-llvm.git] / lib / ExecutionEngine / RuntimeDyld / RuntimeDyldMachO.h
index 48a7253242fa40c7bfc6492ba3e001289eae9969..7d1dc0263db026b1731340fd2a4a441bc30c304c 100644 (file)
 #ifndef LLVM_RUNTIME_DYLD_MACHO_H
 #define LLVM_RUNTIME_DYLD_MACHO_H
 
-#include "llvm/ADT/IndexedMap.h"
-#include "llvm/Object/MachOObject.h"
-#include "llvm/Support/Format.h"
+#include "ObjectImageCommon.h"
 #include "RuntimeDyldImpl.h"
+#include "llvm/Object/MachO.h"
+#include "llvm/Support/Format.h"
+
+#define DEBUG_TYPE "dyld"
 
 using namespace llvm;
 using namespace llvm::object;
 
-
 namespace llvm {
 class RuntimeDyldMachO : public RuntimeDyldImpl {
-
-  // For each symbol, keep a list of relocations based on it. Anytime
-  // its address is reassigned (the JIT re-compiled the function, e.g.),
-  // the relocations get re-resolved.
-  // The symbol (or section) the relocation is sourced from is the Key
-  // in the relocation list where it's stored.
-  struct RelocationEntry {
-    unsigned    SectionID;  // Section the relocation is contained in.
-    uint64_t    Offset;     // Offset into the section for the relocation.
-    uint32_t    Data;       // Second word of the raw macho relocation entry.
-    int64_t     Addend;     // Addend encoded in the instruction itself, if any,
-                            // plus the offset into the source section for
-                            // the symbol once the relocation is resolvable.
-
-    RelocationEntry(unsigned id, uint64_t offset, uint32_t data, int64_t addend)
-      : SectionID(id), Offset(offset), Data(data), Addend(addend) {}
+protected:
+  struct SectionOffsetPair {
+    unsigned SectionID;
+    uint64_t Offset;
   };
-  typedef SmallVector<RelocationEntry, 4> RelocationList;
-
-  // For each section, keep a list of referrers in that section that are clients
-  // of relocations in other sections.  Whenever a relocation gets created,
-  // create a corresponding referrer.  Whenever relocations are re-resolved,
-  // re-resolve the referrers' relocations as well.
-  struct Referrer {
-    unsigned    SectionID;  // Section whose RelocationList contains the relocation.
-    uint32_t    Index;      // Index of the RelocatonEntry in that RelocationList.
-
-    Referrer(unsigned id, uint32_t index)
-      : SectionID(id), Index(index) {}
+
+  struct EHFrameRelatedSections {
+    EHFrameRelatedSections()
+        : EHFrameSID(RTDYLD_INVALID_SECTION_ID),
+          TextSID(RTDYLD_INVALID_SECTION_ID),
+          ExceptTabSID(RTDYLD_INVALID_SECTION_ID) {}
+    EHFrameRelatedSections(SID EH, SID T, SID Ex)
+        : EHFrameSID(EH), TextSID(T), ExceptTabSID(Ex) {}
+    SID EHFrameSID;
+    SID TextSID;
+    SID ExceptTabSID;
   };
-  typedef SmallVector<Referrer, 4> ReferrerList;
-
-  // Relocations to sections already loaded. Indexed by SectionID which is the
-  // source of the address. The target where the address will be writen is
-  // SectionID/Offset in the relocation itself.
-  IndexedMap<RelocationList> Relocations;
-  // Referrers corresponding to Relocations.
-  IndexedMap<ReferrerList> Referrers;
-  // Relocations to symbols that are not yet resolved. Must be external
-  // relocations by definition. Indexed by symbol name.
-  StringMap<RelocationList> UnresolvedRelocations;
-
-  bool resolveRelocation(uint8_t *LocalAddress,
-                         uint64_t FinalAddress,
-                         uint64_t Value,
-                         bool isPCRel,
-                         unsigned Type,
-                         unsigned Size,
-                         int64_t Addend);
-  bool resolveI386Relocation(uint8_t *LocalAddress,
-                             uint64_t FinalAddress,
-                             uint64_t Value,
-                             bool isPCRel,
-                             unsigned Type,
-                             unsigned Size,
-                             int64_t Addend);
-  bool resolveX86_64Relocation(uint8_t *LocalAddress,
-                               uint64_t FinalAddress,
-                               uint64_t Value,
-                               bool isPCRel,
-                               unsigned Type,
-                               unsigned Size,
-                               int64_t Addend);
-  bool resolveARMRelocation(uint8_t *LocalAddress,
-                            uint64_t FinalAddress,
-                            uint64_t Value,
-                            bool isPCRel,
-                            unsigned Type,
-                            unsigned Size,
-                            int64_t Addend);
-
-  bool loadSegment32(const MachOObject *Obj,
-                     const MachOObject::LoadCommandInfo *SegmentLCI,
-                     const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
-  bool loadSegment64(const MachOObject *Obj,
-                     const MachOObject::LoadCommandInfo *SegmentLCI,
-                     const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
-  bool processSymbols32(const MachOObject *Obj,
-                      SmallVectorImpl<unsigned> &SectionMap,
-                      SmallVectorImpl<StringRef> &SymbolNames,
-                      const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
-  bool processSymbols64(const MachOObject *Obj,
-                      SmallVectorImpl<unsigned> &SectionMap,
-                      SmallVectorImpl<StringRef> &SymbolNames,
-                      const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
-
-  void resolveSymbol(StringRef Name);
 
-public:
+  // When a module is loaded we save the SectionID of the EH frame section
+  // in a table until we receive a request to register all unregistered
+  // EH frame sections with the memory manager.
+  SmallVector<EHFrameRelatedSections, 2> UnregisteredEHFrameSections;
+
   RuntimeDyldMachO(RTDyldMemoryManager *mm) : RuntimeDyldImpl(mm) {}
 
-  bool loadObject(MemoryBuffer *InputBuffer);
+  /// Extract the addend encoded in the instruction.
+  uint64_t decodeAddend(uint8_t *LocalAddress, unsigned NumBytes,
+                        uint32_t RelType) const;
+
+  /// Construct a RelocationValueRef representing the relocation target.
+  /// For Symbols in known sections, this will return a RelocationValueRef
+  /// representing a (SectionID, Offset) pair.
+  /// For Symbols whose section is not known, this will return a
+  /// (SymbolName, Offset) pair, where the Offset is taken from the instruction
+  /// immediate (held in RE.Addend).
+  /// In both cases the Addend field is *NOT* fixed up to be PC-relative. That
+  /// should be done by the caller where appropriate by calling makePCRel on
+  /// the RelocationValueRef.
+  RelocationValueRef getRelocationValueRef(ObjectImage &ObjImg,
+                                           const relocation_iterator &RI,
+                                           const RelocationEntry &RE,
+                                           ObjSectionToIDMap &ObjSectionToID,
+                                           const SymbolTableMap &Symbols);
+
+  /// Make the RelocationValueRef addend PC-relative.
+  void makeValueAddendPCRel(RelocationValueRef &Value, ObjectImage &ObjImg,
+                            const relocation_iterator &RI);
+
+  /// Dump information about the relocation entry (RE) and resolved value.
+  void dumpRelocationToResolve(const RelocationEntry &RE, uint64_t Value) const;
+
+public:
+  /// Create an ObjectImage from the given ObjectBuffer.
+  static ObjectImage *createObjectImage(ObjectBuffer *InputBuffer) {
+    return new ObjectImageCommon(InputBuffer);
+  }
+
+  /// Create an ObjectImage from the given ObjectFile.
+  static ObjectImage *
+  createObjectImageFromFile(std::unique_ptr<object::ObjectFile> InputObject) {
+    return new ObjectImageCommon(std::move(InputObject));
+  }
+
+  /// Create a RuntimeDyldMachO instance for the given target architecture.
+  static std::unique_ptr<RuntimeDyldMachO> create(Triple::ArchType Arch,
+                                                  RTDyldMemoryManager *mm);
+
+  /// Write the least significant 'Size' bytes in 'Value' out at the address
+  /// pointed to by Addr. Check for overflow.
+  bool writeBytesUnaligned(uint8_t *Addr, uint64_t Value, unsigned Size);
 
-  void reassignSectionAddress(unsigned SectionID, uint64_t Addr);
+  SectionEntry &getSection(unsigned SectionID) { return Sections[SectionID]; }
 
-  static bool isKnownFormat(const MemoryBuffer *InputBuffer);
+  bool isCompatibleFormat(const ObjectBuffer *Buffer) const override;
+  bool isCompatibleFile(const object::ObjectFile *Obj) const override;
+  void registerEHFrames() override;
+};
 
-  bool isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
-    return isKnownFormat(InputBuffer);
+/// RuntimeDyldMachOTarget - Templated base class for generic MachO linker
+/// algorithms and data structures.
+///
+/// Concrete, target specific sub-classes can be accessed via the impl()
+/// methods. (i.e. the RuntimeDyldMachO hierarchy uses the Curiously
+/// Recurring Template Idiom). Concrete subclasses for each target
+/// can be found in ./Targets.
+template <typename Impl>
+class RuntimeDyldMachOCRTPBase : public RuntimeDyldMachO {
+private:
+  Impl &impl() { return static_cast<Impl &>(*this); }
+  const Impl &impl() const { return static_cast<const Impl &>(*this); }
+
+protected:
+
+  /// Parse the given relocation, which must be a non-scattered, and
+  /// return a RelocationEntry representing the information. The 'Addend' field
+  /// will contain the unmodified instruction immediate.
+  RelocationEntry getBasicRelocationEntry(unsigned SectionID,
+                                          ObjectImage &ObjImg,
+                                          const relocation_iterator &RI) const {
+    const MachOObjectFile &Obj =
+      static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile());
+    MachO::any_relocation_info RelInfo =
+      Obj.getRelocation(RI->getRawDataRefImpl());
+
+    const SectionEntry &Section = Sections[SectionID];
+    bool IsPCRel = Obj.getAnyRelocationPCRel(RelInfo);
+    unsigned Size = Obj.getAnyRelocationLength(RelInfo);
+    uint64_t Offset;
+    RI->getOffset(Offset);
+    uint8_t *LocalAddress = Section.Address + Offset;
+    unsigned NumBytes = 1 << Size;
+    uint32_t RelType = Obj.getAnyRelocationType(RelInfo);
+    uint64_t Addend = impl().decodeAddend(LocalAddress, NumBytes, RelType);
+
+    return RelocationEntry(SectionID, Offset, RelType, Addend, IsPCRel, Size);
+  }
+
+public:
+  RuntimeDyldMachOCRTPBase(RTDyldMemoryManager *mm) : RuntimeDyldMachO(mm) {}
+
+  void finalizeLoad(ObjectImage &ObjImg, ObjSectionToIDMap &SectionMap) {
+    unsigned EHFrameSID = RTDYLD_INVALID_SECTION_ID;
+    unsigned TextSID = RTDYLD_INVALID_SECTION_ID;
+    unsigned ExceptTabSID = RTDYLD_INVALID_SECTION_ID;
+    ObjSectionToIDMap::iterator i, e;
+
+    for (i = SectionMap.begin(), e = SectionMap.end(); i != e; ++i) {
+      const SectionRef &Section = i->first;
+      StringRef Name;
+      Section.getName(Name);
+      if (Name == "__eh_frame")
+        EHFrameSID = i->second;
+      else if (Name == "__text")
+        TextSID = i->second;
+      else if (Name == "__gcc_except_tab")
+        ExceptTabSID = i->second;
+      else
+        impl().finalizeSection(ObjImg, i->second, Section);
+    }
+    UnregisteredEHFrameSections.push_back(
+        EHFrameRelatedSections(EHFrameSID, TextSID, ExceptTabSID));
   }
 };
 
 } // end namespace llvm
 
+#undef DEBUG_TYPE
+
 #endif