[RuntimeDyld][COFF] Add external symbol resolution support to RuntimeDyldCOFF.

[oota-llvm.git] / lib / ExecutionEngine / RuntimeDyld / Targets / RuntimeDyldCOFFX86_64.h

diff --git a/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
index fe5ae90fc86b090dcda3e1bbe7b49ee32035142e..478665ea3d011ed7ce33ae76c1a02fca5004ba47 100644 (file)
--- a/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
+++ b/lib/ExecutionEngine/RuntimeDyld/Targets/RuntimeDyldCOFFX86_64.h
@@ -18,7 +18,7 @@
 #include "llvm/Support/COFF.h"
 #include "../RuntimeDyldCOFF.h"
 
 #include "llvm/Support/COFF.h"
 #include "../RuntimeDyldCOFF.h"
 

-using namespace llvm;
+#define DEBUG_TYPE "dyld"

 
 namespace llvm {
 
 
 namespace llvm {
 


@@ -32,25 +32,181 @@ private:
   SmallVector<SID, 2> RegisteredEHFrameSections;
 
 public:
   SmallVector<SID, 2> RegisteredEHFrameSections;
 
 public:

-  RuntimeDyldCOFFX86_64(RTDyldMemoryManager *MM) : RuntimeDyldCOFF(MM) {}
+  RuntimeDyldCOFFX86_64(RuntimeDyld::MemoryManager &MM,
+                        RuntimeDyld::SymbolResolver &Resolver)
+    : RuntimeDyldCOFF(MM, Resolver) {}

 
   unsigned getMaxStubSize() override {
     return 6; // 2-byte jmp instruction + 32-bit relative address
   }
 
 
   unsigned getMaxStubSize() override {
     return 6; // 2-byte jmp instruction + 32-bit relative address
   }
 

-  void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override;
+  // The target location for the relocation is described by RE.SectionID and
+  // RE.Offset.  RE.SectionID can be used to find the SectionEntry.  Each
+  // SectionEntry has three members describing its location.
+  // SectionEntry::Address is the address at which the section has been loaded
+  // into memory in the current (host) process.  SectionEntry::LoadAddress is
+  // the address that the section will have in the target process.
+  // SectionEntry::ObjAddress is the address of the bits for this section in the
+  // original emitted object image (also in the current address space).
+  //
+  // Relocations will be applied as if the section were loaded at
+  // SectionEntry::LoadAddress, but they will be applied at an address based
+  // on SectionEntry::Address.  SectionEntry::ObjAddress will be used to refer
+  // to Target memory contents if they are required for value calculations.
+  //
+  // The Value parameter here is the load address of the symbol for the
+  // relocation to be applied.  For relocations which refer to symbols in the
+  // current object Value will be the LoadAddress of the section in which
+  // the symbol resides (RE.Addend provides additional information about the
+  // symbol location).  For external symbols, Value will be the address of the
+  // symbol in the target address space.
+  void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override {
+    const SectionEntry &Section = Sections[RE.SectionID];
+    uint8_t *Target = Section.Address + RE.Offset;
+
+    switch (RE.RelType) {
+
+    case COFF::IMAGE_REL_AMD64_REL32:
+    case COFF::IMAGE_REL_AMD64_REL32_1:
+    case COFF::IMAGE_REL_AMD64_REL32_2:
+    case COFF::IMAGE_REL_AMD64_REL32_3:
+    case COFF::IMAGE_REL_AMD64_REL32_4:
+    case COFF::IMAGE_REL_AMD64_REL32_5: {
+      uint32_t *TargetAddress = (uint32_t *)Target;
+      uint64_t FinalAddress = Section.LoadAddress + RE.Offset;
+      // Delta is the distance from the start of the reloc to the end of the
+      // instruction with the reloc.
+      uint64_t Delta = 4 + (RE.RelType - COFF::IMAGE_REL_AMD64_REL32);
+      Value -= FinalAddress + Delta;
+      uint64_t Result = Value + RE.Addend;
+      assert(((int64_t)Result <= INT32_MAX) && "Relocation overflow");
+      assert(((int64_t)Result >= INT32_MIN) && "Relocation underflow");
+      *TargetAddress = Result;
+      break;
+    }
+
+    case COFF::IMAGE_REL_AMD64_ADDR32NB: {
+      // Note ADDR32NB requires a well-established notion of
+      // image base. This address must be less than or equal
+      // to every section's load address, and all sections must be
+      // within a 32 bit offset from the base.
+      //
+      // For now we just set these to zero.
+      uint32_t *TargetAddress = (uint32_t *)Target;
+      *TargetAddress = 0;
+      break;
+    }
+
+    case COFF::IMAGE_REL_AMD64_ADDR64: {
+      uint64_t *TargetAddress = (uint64_t *)Target;
+      *TargetAddress = Value + RE.Addend;
+      break;
+    }
+
+    default:
+      llvm_unreachable("Relocation type not implemented yet!");
+      break;
+    }
+  }

 
   relocation_iterator processRelocationRef(unsigned SectionID,
                                            relocation_iterator RelI,
                                            const ObjectFile &Obj,
                                            ObjSectionToIDMap &ObjSectionToID,
 
   relocation_iterator processRelocationRef(unsigned SectionID,
                                            relocation_iterator RelI,
                                            const ObjectFile &Obj,
                                            ObjSectionToIDMap &ObjSectionToID,

-                                           StubMap &Stubs) override;
+                                           StubMap &Stubs) override {
+    // If possible, find the symbol referred to in the relocation,
+    // and the section that contains it.
+    symbol_iterator Symbol = RelI->getSymbol();
+    if (Symbol == Obj.symbol_end())
+      report_fatal_error("Unknown symbol in relocation");
+    section_iterator SecI(Obj.section_end());
+    Symbol->getSection(SecI);
+    // If there is no section, this must be an external reference.
+    const bool IsExtern = SecI == Obj.section_end();
+
+    // Determine the Addend used to adjust the relocation value.
+    uint64_t RelType;
+    Check(RelI->getType(RelType));
+    uint64_t Offset;
+    Check(RelI->getOffset(Offset));
+    uint64_t Addend = 0;
+    SectionEntry &Section = Sections[SectionID];
+    uintptr_t ObjTarget = Section.ObjAddress + Offset;
+
+    switch (RelType) {
+
+    case COFF::IMAGE_REL_AMD64_REL32:
+    case COFF::IMAGE_REL_AMD64_REL32_1:
+    case COFF::IMAGE_REL_AMD64_REL32_2:
+    case COFF::IMAGE_REL_AMD64_REL32_3:
+    case COFF::IMAGE_REL_AMD64_REL32_4:
+    case COFF::IMAGE_REL_AMD64_REL32_5:
+    case COFF::IMAGE_REL_AMD64_ADDR32NB: {
+      uint32_t *Displacement = (uint32_t *)ObjTarget;
+      Addend = *Displacement;
+      break;
+    }
+
+    case COFF::IMAGE_REL_AMD64_ADDR64: {
+      uint64_t *Displacement = (uint64_t *)ObjTarget;
+      Addend = *Displacement;
+      break;
+    }
+
+    default:
+      break;
+    }
+
+    StringRef TargetName;
+    Symbol->getName(TargetName);
+
+    DEBUG(dbgs() << "\t\tIn Section " << SectionID << " Offset " << Offset
+                 << " RelType: " << RelType << " TargetName: " << TargetName
+                 << " Addend " << Addend << "\n");
+
+    if (IsExtern) {
+      RelocationEntry RE(SectionID, Offset, RelType, Addend);
+      addRelocationForSymbol(RE, TargetName);
+    } else {
+      bool IsCode = SecI->isText();
+      unsigned TargetSectionID =
+          findOrEmitSection(Obj, *SecI, IsCode, ObjSectionToID);
+      uint64_t TargetOffset = getSymbolOffset(*Symbol);
+      RelocationEntry RE(SectionID, Offset, RelType, TargetOffset + Addend);
+      addRelocationForSection(RE, TargetSectionID);
+    }
+
+    return ++RelI;
+  }

 
   unsigned getStubAlignment() override { return 1; }
 
   unsigned getStubAlignment() override { return 1; }

-  void registerEHFrames() override;
-  void deregisterEHFrames() override;
+  void registerEHFrames() override {
+    for (auto const &EHFrameSID : UnregisteredEHFrameSections) {
+      uint8_t *EHFrameAddr = Sections[EHFrameSID].Address;
+      uint64_t EHFrameLoadAddr = Sections[EHFrameSID].LoadAddress;
+      size_t EHFrameSize = Sections[EHFrameSID].Size;
+      MemMgr.registerEHFrames(EHFrameAddr, EHFrameLoadAddr, EHFrameSize);
+      RegisteredEHFrameSections.push_back(EHFrameSID);
+    }
+    UnregisteredEHFrameSections.clear();
+  }
+  void deregisterEHFrames() override {
+    // Stub
+  }

   void finalizeLoad(const ObjectFile &Obj,
   void finalizeLoad(const ObjectFile &Obj,

-                    ObjSectionToIDMap &SectionMap) override;
+                    ObjSectionToIDMap &SectionMap) override {
+    // Look for and record the EH frame section IDs.
+    for (const auto &SectionPair : SectionMap) {
+      const SectionRef &Section = SectionPair.first;
+      StringRef Name;
+      Check(Section.getName(Name));
+      // Note unwind info is split across .pdata and .xdata, so this
+      // may not be sufficiently general for all users.
+      if (Name == ".xdata") {
+        UnregisteredEHFrameSections.push_back(SectionPair.second);
+      }
+    }
+  }

 };
 
 } // end namespace llvm
 };
 
 } // end namespace llvm