[RuntimeDyld] Skip relocations for external symbols with 64-bit address ~0ULL.
[oota-llvm.git] / lib / ExecutionEngine / RuntimeDyld / RuntimeDyldMachO.cpp
index ddd828244a53ad6bfa77c51907e83e9e49606c64..74b13d60a984f72a8a0288c0d91dd2703528555c 100644 (file)
 //===----------------------------------------------------------------------===//
 
 #include "RuntimeDyldMachO.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/StringRef.h"
-
-#include "Targets/RuntimeDyldMachOARM.h"
 #include "Targets/RuntimeDyldMachOAArch64.h"
+#include "Targets/RuntimeDyldMachOARM.h"
 #include "Targets/RuntimeDyldMachOI386.h"
 #include "Targets/RuntimeDyldMachOX86_64.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringRef.h"
 
 using namespace llvm;
 using namespace llvm::object;
 
 #define DEBUG_TYPE "dyld"
 
+namespace {
+
+class LoadedMachOObjectInfo
+    : public RuntimeDyld::LoadedObjectInfoHelper<LoadedMachOObjectInfo> {
+public:
+  LoadedMachOObjectInfo(RuntimeDyldImpl &RTDyld, unsigned BeginIdx,
+                        unsigned EndIdx)
+      : LoadedObjectInfoHelper(RTDyld, BeginIdx, EndIdx) {}
+
+  OwningBinary<ObjectFile>
+  getObjectForDebug(const ObjectFile &Obj) const override {
+    return OwningBinary<ObjectFile>();
+  }
+};
+
+}
+
 namespace llvm {
 
 int64_t RuntimeDyldMachO::memcpyAddend(const RelocationEntry &RE) const {
@@ -35,12 +51,11 @@ int64_t RuntimeDyldMachO::memcpyAddend(const RelocationEntry &RE) const {
 }
 
 RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
-    ObjectImage &ObjImg, const relocation_iterator &RI,
-    const RelocationEntry &RE, ObjSectionToIDMap &ObjSectionToID,
-    const SymbolTableMap &Symbols) {
+    const ObjectFile &BaseTObj, const relocation_iterator &RI,
+    const RelocationEntry &RE, ObjSectionToIDMap &ObjSectionToID) {
 
   const MachOObjectFile &Obj =
-      static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile());
+      static_cast<const MachOObjectFile &>(BaseTObj);
   MachO::any_relocation_info RelInfo =
       Obj.getRelocation(RI->getRawDataRefImpl());
   RelocationValueRef Value;
@@ -48,26 +63,24 @@ RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
   bool IsExternal = Obj.getPlainRelocationExternal(RelInfo);
   if (IsExternal) {
     symbol_iterator Symbol = RI->getSymbol();
-    StringRef TargetName;
-    Symbol->getName(TargetName);
-    SymbolTableMap::const_iterator SI = Symbols.find(TargetName.data());
-    if (SI != Symbols.end()) {
-      Value.SectionID = SI->second.first;
-      Value.Offset = SI->second.second + RE.Addend;
+    ErrorOr<StringRef> TargetNameOrErr = Symbol->getName();
+    if (std::error_code EC = TargetNameOrErr.getError())
+      report_fatal_error(EC.message());
+    StringRef TargetName = *TargetNameOrErr;
+    RTDyldSymbolTable::const_iterator SI =
+      GlobalSymbolTable.find(TargetName.data());
+    if (SI != GlobalSymbolTable.end()) {
+      const auto &SymInfo = SI->second;
+      Value.SectionID = SymInfo.getSectionID();
+      Value.Offset = SymInfo.getOffset() + RE.Addend;
     } else {
-      SI = GlobalSymbolTable.find(TargetName.data());
-      if (SI != GlobalSymbolTable.end()) {
-        Value.SectionID = SI->second.first;
-        Value.Offset = SI->second.second + RE.Addend;
-      } else {
-        Value.SymbolName = TargetName.data();
-        Value.Offset = RE.Addend;
-      }
+      Value.SymbolName = TargetName.data();
+      Value.Offset = RE.Addend;
     }
   } else {
-    SectionRef Sec = Obj.getRelocationSection(RelInfo);
+    SectionRef Sec = Obj.getAnyRelocationSection(RelInfo);
     bool IsCode = Sec.isText();
-    Value.SectionID = findOrEmitSection(ObjImg, Sec, IsCode, ObjSectionToID);
+    Value.SectionID = findOrEmitSection(Obj, Sec, IsCode, ObjSectionToID);
     uint64_t Addr = Sec.getAddress();
     Value.Offset = RE.Addend - Addr;
   }
@@ -76,19 +89,18 @@ RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
 }
 
 void RuntimeDyldMachO::makeValueAddendPCRel(RelocationValueRef &Value,
-                                            ObjectImage &ObjImg,
+                                            const ObjectFile &BaseTObj,
                                             const relocation_iterator &RI,
                                             unsigned OffsetToNextPC) {
   const MachOObjectFile &Obj =
-      static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile());
+      static_cast<const MachOObjectFile &>(BaseTObj);
   MachO::any_relocation_info RelInfo =
       Obj.getRelocation(RI->getRawDataRefImpl());
 
   bool IsPCRel = Obj.getAnyRelocationPCRel(RelInfo);
   if (IsPCRel) {
-    uint64_t RelocAddr = 0;
-    RI->getAddress(RelocAddr);
-    Value.Offset += RelocAddr + OffsetToNextPC;
+    ErrorOr<uint64_t> RelocAddr = RI->getAddress();
+    Value.Offset += *RelocAddr + OffsetToNextPC;
   }
 }
 
@@ -125,7 +137,7 @@ RuntimeDyldMachO::getSectionByAddress(const MachOObjectFile &Obj,
 
 // Populate __pointers section.
 void RuntimeDyldMachO::populateIndirectSymbolPointersSection(
-                                                    MachOObjectFile &Obj,
+                                                    const MachOObjectFile &Obj,
                                                     const SectionRef &PTSection,
                                                     unsigned PTSectionID) {
   assert(!Obj.is64Bit() &&
@@ -152,8 +164,10 @@ void RuntimeDyldMachO::populateIndirectSymbolPointersSection(
     unsigned SymbolIndex =
       Obj.getIndirectSymbolTableEntry(DySymTabCmd, FirstIndirectSymbol + i);
     symbol_iterator SI = Obj.getSymbolByIndex(SymbolIndex);
-    StringRef IndirectSymbolName;
-    SI->getName(IndirectSymbolName);
+    ErrorOr<StringRef> IndirectSymbolNameOrErr = SI->getName();
+    if (std::error_code EC = IndirectSymbolNameOrErr.getError())
+      report_fatal_error(EC.message());
+    StringRef IndirectSymbolName = *IndirectSymbolNameOrErr;
     DEBUG(dbgs() << "  " << IndirectSymbolName << ": index " << SymbolIndex
           << ", PT offset: " << PTEntryOffset << "\n");
     RelocationEntry RE(PTSectionID, PTEntryOffset,
@@ -163,46 +177,35 @@ void RuntimeDyldMachO::populateIndirectSymbolPointersSection(
   }
 }
 
-bool
-RuntimeDyldMachO::isCompatibleFormat(const ObjectBuffer *InputBuffer) const {
-  if (InputBuffer->getBufferSize() < 4)
-    return false;
-  StringRef Magic(InputBuffer->getBufferStart(), 4);
-  if (Magic == "\xFE\xED\xFA\xCE")
-    return true;
-  if (Magic == "\xCE\xFA\xED\xFE")
-    return true;
-  if (Magic == "\xFE\xED\xFA\xCF")
-    return true;
-  if (Magic == "\xCF\xFA\xED\xFE")
-    return true;
-  return false;
-}
-
-bool RuntimeDyldMachO::isCompatibleFile(const object::ObjectFile *Obj) const {
-  return Obj->isMachO();
+bool RuntimeDyldMachO::isCompatibleFile(const object::ObjectFile &Obj) const {
+  return Obj.isMachO();
 }
 
 template <typename Impl>
-void RuntimeDyldMachOCRTPBase<Impl>::finalizeLoad(ObjectImage &ObjImg,
+void RuntimeDyldMachOCRTPBase<Impl>::finalizeLoad(const ObjectFile &Obj,
                                                   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;
+  for (const auto &Section : Obj.sections()) {
     StringRef Name;
     Section.getName(Name);
-    if (Name == "__eh_frame")
-      EHFrameSID = i->second;
-    else if (Name == "__text")
-      TextSID = i->second;
+
+    // Force emission of the __text, __eh_frame, and __gcc_except_tab sections
+    // if they're present. Otherwise call down to the impl to handle other
+    // sections that have already been emitted.
+    if (Name == "__text")
+      TextSID = findOrEmitSection(Obj, Section, true, SectionMap);
+    else if (Name == "__eh_frame")
+      EHFrameSID = findOrEmitSection(Obj, Section, false, SectionMap);
     else if (Name == "__gcc_except_tab")
-      ExceptTabSID = i->second;
-    else
-      impl().finalizeSection(ObjImg, i->second, Section);
+      ExceptTabSID = findOrEmitSection(Obj, Section, true, SectionMap);
+    else {
+      auto I = SectionMap.find(Section);
+      if (I != SectionMap.end())
+        impl().finalizeSection(Obj, I->second, Section);
+    }
   }
   UnregisteredEHFrameSections.push_back(
     EHFrameRelatedSections(EHFrameSID, TextSID, ExceptTabSID));
@@ -216,17 +219,18 @@ unsigned char *RuntimeDyldMachOCRTPBase<Impl>::processFDE(unsigned char *P,
 
   DEBUG(dbgs() << "Processing FDE: Delta for text: " << DeltaForText
                << ", Delta for EH: " << DeltaForEH << "\n");
-  uint32_t Length = *((uint32_t *)P);
+  uint32_t Length = readBytesUnaligned(P, 4);
   P += 4;
   unsigned char *Ret = P + Length;
-  uint32_t Offset = *((uint32_t *)P);
+  uint32_t Offset = readBytesUnaligned(P, 4);
   if (Offset == 0) // is a CIE
     return Ret;
 
   P += 4;
-  TargetPtrT FDELocation = *((TargetPtrT*)P);
+  TargetPtrT FDELocation = readBytesUnaligned(P, sizeof(TargetPtrT));
   TargetPtrT NewLocation = FDELocation - DeltaForText;
-  *((TargetPtrT*)P) = NewLocation;
+  writeBytesUnaligned(NewLocation, P, sizeof(TargetPtrT));
+
   P += sizeof(TargetPtrT);
 
   // Skip the FDE address range
@@ -235,16 +239,17 @@ unsigned char *RuntimeDyldMachOCRTPBase<Impl>::processFDE(unsigned char *P,
   uint8_t Augmentationsize = *P;
   P += 1;
   if (Augmentationsize != 0) {
-    TargetPtrT LSDA = *((TargetPtrT *)P);
+    TargetPtrT LSDA = readBytesUnaligned(P, sizeof(TargetPtrT));
     TargetPtrT NewLSDA = LSDA - DeltaForEH;
-    *((TargetPtrT *)P) = NewLSDA;
+    writeBytesUnaligned(NewLSDA, P, sizeof(TargetPtrT));
   }
 
   return Ret;
 }
 
 static int64_t computeDelta(SectionEntry *A, SectionEntry *B) {
-  int64_t ObjDistance = A->ObjAddress - B->ObjAddress;
+  int64_t ObjDistance =
+    static_cast<int64_t>(A->ObjAddress) - static_cast<int64_t>(B->ObjAddress);
   int64_t MemDistance = A->LoadAddress - B->LoadAddress;
   return ObjDistance - MemDistance;
 }
@@ -252,8 +257,6 @@ static int64_t computeDelta(SectionEntry *A, SectionEntry *B) {
 template <typename Impl>
 void RuntimeDyldMachOCRTPBase<Impl>::registerEHFrames() {
 
-  if (!MemMgr)
-    return;
   for (int i = 0, e = UnregisteredEHFrameSections.size(); i != e; ++i) {
     EHFrameRelatedSections &SectionInfo = UnregisteredEHFrameSections[i];
     if (SectionInfo.EHFrameSID == RTDYLD_INVALID_SECTION_ID ||
@@ -276,23 +279,37 @@ void RuntimeDyldMachOCRTPBase<Impl>::registerEHFrames() {
       P = processFDE(P, DeltaForText, DeltaForEH);
     } while (P != End);
 
-    MemMgr->registerEHFrames(EHFrame->Address, EHFrame->LoadAddress,
-                             EHFrame->Size);
+    MemMgr.registerEHFrames(EHFrame->Address, EHFrame->LoadAddress,
+                            EHFrame->Size);
   }
   UnregisteredEHFrameSections.clear();
 }
 
 std::unique_ptr<RuntimeDyldMachO>
-llvm::RuntimeDyldMachO::create(Triple::ArchType Arch, RTDyldMemoryManager *MM) {
+RuntimeDyldMachO::create(Triple::ArchType Arch,
+                         RuntimeDyld::MemoryManager &MemMgr,
+                         RuntimeDyld::SymbolResolver &Resolver) {
   switch (Arch) {
   default:
     llvm_unreachable("Unsupported target for RuntimeDyldMachO.");
     break;
-  case Triple::arm: return make_unique<RuntimeDyldMachOARM>(MM);
-  case Triple::aarch64: return make_unique<RuntimeDyldMachOAArch64>(MM);
-  case Triple::x86: return make_unique<RuntimeDyldMachOI386>(MM);
-  case Triple::x86_64: return make_unique<RuntimeDyldMachOX86_64>(MM);
+  case Triple::arm:
+    return make_unique<RuntimeDyldMachOARM>(MemMgr, Resolver);
+  case Triple::aarch64:
+    return make_unique<RuntimeDyldMachOAArch64>(MemMgr, Resolver);
+  case Triple::x86:
+    return make_unique<RuntimeDyldMachOI386>(MemMgr, Resolver);
+  case Triple::x86_64:
+    return make_unique<RuntimeDyldMachOX86_64>(MemMgr, Resolver);
   }
 }
 
+std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
+RuntimeDyldMachO::loadObject(const object::ObjectFile &O) {
+  unsigned SectionStartIdx, SectionEndIdx;
+  std::tie(SectionStartIdx, SectionEndIdx) = loadObjectImpl(O);
+  return llvm::make_unique<LoadedMachOObjectInfo>(*this, SectionStartIdx,
+                                                  SectionEndIdx);
+}
+
 } // end namespace llvm