Don't return error_code from function that never fails.
[oota-llvm.git] / lib / ExecutionEngine / RuntimeDyld / Targets / RuntimeDyldMachOARM.h
index dc8acfef5b7dc666b4b5f44f629f371895a495fc..0d9445e84f099c0921126143480c5022de31ed03 100644 (file)
@@ -25,7 +25,9 @@ public:
 
   typedef uint32_t TargetPtrT;
 
-  RuntimeDyldMachOARM(RTDyldMemoryManager *MM) : RuntimeDyldMachOCRTPBase(MM) {}
+  RuntimeDyldMachOARM(RuntimeDyld::MemoryManager &MM,
+                      RuntimeDyld::SymbolResolver &Resolver)
+    : RuntimeDyldMachOCRTPBase(MM, Resolver) {}
 
   unsigned getMaxStubSize() override { return 8; }
 
@@ -39,8 +41,7 @@ public:
       default:
         return memcpyAddend(RE);
       case MachO::ARM_RELOC_BR24: {
-        uint32_t Temp;
-        memcpy(&Temp, LocalAddress, 4);
+        uint32_t Temp = readBytesUnaligned(LocalAddress, 4);
         Temp &= 0x00ffffff; // Mask out the opcode.
         // Now we've got the shifted immediate, shift by 2, sign extend and ret.
         return SignExtend32<26>(Temp << 2);
@@ -50,23 +51,30 @@ public:
 
   relocation_iterator
   processRelocationRef(unsigned SectionID, relocation_iterator RelI,
-                       ObjectImage &ObjImg, ObjSectionToIDMap &ObjSectionToID,
-                       const SymbolTableMap &Symbols, StubMap &Stubs) override {
+                       const ObjectFile &BaseObjT,
+                       ObjSectionToIDMap &ObjSectionToID,
+                       StubMap &Stubs) override {
     const MachOObjectFile &Obj =
-        static_cast<const MachOObjectFile &>(*ObjImg.getObjectFile());
+        static_cast<const MachOObjectFile &>(BaseObjT);
     MachO::any_relocation_info RelInfo =
         Obj.getRelocation(RelI->getRawDataRefImpl());
+    uint32_t RelType = Obj.getAnyRelocationType(RelInfo);
 
-    if (Obj.isRelocationScattered(RelInfo))
-      return ++++RelI;
+    if (Obj.isRelocationScattered(RelInfo)) {
+      if (RelType == MachO::ARM_RELOC_HALF_SECTDIFF)
+        return processHALFSECTDIFFRelocation(SectionID, RelI, Obj,
+                                             ObjSectionToID);
+      else
+        return ++++RelI;
+    }
 
-    RelocationEntry RE(getRelocationEntry(SectionID, ObjImg, RelI));
+    RelocationEntry RE(getRelocationEntry(SectionID, Obj, RelI));
     RE.Addend = decodeAddend(RE);
     RelocationValueRef Value(
-        getRelocationValueRef(ObjImg, RelI, RE, ObjSectionToID, Symbols));
+        getRelocationValueRef(Obj, RelI, RE, ObjSectionToID));
 
     if (RE.IsPCRel)
-      makeValueAddendPCRel(Value, ObjImg, RelI, 8);
+      makeValueAddendPCRel(Value, Obj, RelI, 8);
 
     if ((RE.RelType & 0xf) == MachO::ARM_RELOC_BR24)
       processBranchRelocation(RE, Value, Stubs);
@@ -106,7 +114,6 @@ public:
     case MachO::ARM_RELOC_BR24: {
       // Mask the value into the target address. We know instructions are
       // 32-bit aligned, so we can do it all at once.
-      uint32_t *p = (uint32_t *)LocalAddress;
       Value += RE.Addend;
       // The low two bits of the value are not encoded.
       Value >>= 2;
@@ -117,13 +124,30 @@ public:
       // instruction instead.
 
       // Insert the value into the instruction.
-      *p = (*p & ~0xffffff) | FinalValue;
+      uint32_t Temp = readBytesUnaligned(LocalAddress, 4);
+      writeBytesUnaligned((Temp & ~0xffffff) | FinalValue, LocalAddress, 4);
+
       break;
     }
+    case MachO::ARM_RELOC_HALF_SECTDIFF: {
+      uint64_t SectionABase = Sections[RE.Sections.SectionA].LoadAddress;
+      uint64_t SectionBBase = Sections[RE.Sections.SectionB].LoadAddress;
+      assert((Value == SectionABase || Value == SectionBBase) &&
+             "Unexpected HALFSECTDIFF relocation value.");
+      Value = SectionABase - SectionBBase + RE.Addend;
+      if (RE.Size & 0x1) // :upper16:
+        Value = (Value >> 16);
+      Value &= 0xffff;
+
+      uint32_t Insn = readBytesUnaligned(LocalAddress, 4);
+      Insn = (Insn & 0xfff0f000) | ((Value & 0xf000) << 4) | (Value & 0x0fff);
+      writeBytesUnaligned(Insn, LocalAddress, 4);
+      break;
+    }
+
     case MachO::ARM_THUMB_RELOC_BR22:
     case MachO::ARM_THUMB_32BIT_BRANCH:
     case MachO::ARM_RELOC_HALF:
-    case MachO::ARM_RELOC_HALF_SECTDIFF:
     case MachO::ARM_RELOC_PAIR:
     case MachO::ARM_RELOC_SECTDIFF:
     case MachO::ARM_RELOC_LOCAL_SECTDIFF:
@@ -133,10 +157,18 @@ public:
     }
   }
 
-  void finalizeSection(ObjectImage &ObjImg, unsigned SectionID,
-                       const SectionRef &Section) {}
+  void finalizeSection(const ObjectFile &Obj, unsigned SectionID,
+                       const SectionRef &Section) {
+    StringRef Name;
+    Section.getName(Name);
+
+    if (Name == "__nl_symbol_ptr")
+      populateIndirectSymbolPointersSection(cast<MachOObjectFile>(Obj),
+                                            Section, SectionID);
+  }
 
 private:
+
   void processBranchRelocation(const RelocationEntry &RE,
                                const RelocationValueRef &Value,
                                StubMap &Stubs) {
@@ -166,6 +198,78 @@ private:
                              RE.IsPCRel, RE.Size);
     resolveRelocation(TargetRE, (uint64_t)Addr);
   }
+
+  relocation_iterator
+  processHALFSECTDIFFRelocation(unsigned SectionID, relocation_iterator RelI,
+                                const ObjectFile &BaseTObj,
+                                ObjSectionToIDMap &ObjSectionToID) {
+    const MachOObjectFile &MachO =
+        static_cast<const MachOObjectFile&>(BaseTObj);
+    MachO::any_relocation_info RE =
+        MachO.getRelocation(RelI->getRawDataRefImpl());
+
+
+    // For a half-diff relocation the length bits actually record whether this
+    // is a movw/movt, and whether this is arm or thumb.
+    // Bit 0 indicates movw (b0 == 0) or movt (b0 == 1).
+    // Bit 1 indicates arm (b1 == 0) or thumb (b1 == 1).
+    unsigned HalfDiffKindBits = MachO.getAnyRelocationLength(RE);
+    if (HalfDiffKindBits & 0x2)
+      llvm_unreachable("Thumb not yet supported.");
+
+    SectionEntry &Section = Sections[SectionID];
+    uint32_t RelocType = MachO.getAnyRelocationType(RE);
+    bool IsPCRel = MachO.getAnyRelocationPCRel(RE);
+    uint64_t Offset = RelI->getOffset();
+    uint8_t *LocalAddress = Section.Address + Offset;
+    int64_t Immediate = readBytesUnaligned(LocalAddress, 4); // Copy the whole instruction out.
+    Immediate = ((Immediate >> 4) & 0xf000) | (Immediate & 0xfff);
+
+    ++RelI;
+    MachO::any_relocation_info RE2 =
+      MachO.getRelocation(RelI->getRawDataRefImpl());
+    uint32_t AddrA = MachO.getScatteredRelocationValue(RE);
+    section_iterator SAI = getSectionByAddress(MachO, AddrA);
+    assert(SAI != MachO.section_end() && "Can't find section for address A");
+    uint64_t SectionABase = SAI->getAddress();
+    uint64_t SectionAOffset = AddrA - SectionABase;
+    SectionRef SectionA = *SAI;
+    bool IsCode = SectionA.isText();
+    uint32_t SectionAID =
+        findOrEmitSection(MachO, SectionA, IsCode, ObjSectionToID);
+
+    uint32_t AddrB = MachO.getScatteredRelocationValue(RE2);
+    section_iterator SBI = getSectionByAddress(MachO, AddrB);
+    assert(SBI != MachO.section_end() && "Can't find section for address B");
+    uint64_t SectionBBase = SBI->getAddress();
+    uint64_t SectionBOffset = AddrB - SectionBBase;
+    SectionRef SectionB = *SBI;
+    uint32_t SectionBID =
+        findOrEmitSection(MachO, SectionB, IsCode, ObjSectionToID);
+
+    uint32_t OtherHalf = MachO.getAnyRelocationAddress(RE2) & 0xffff;
+    unsigned Shift = (HalfDiffKindBits & 0x1) ? 16 : 0;
+    uint32_t FullImmVal = (Immediate << Shift) | (OtherHalf << (16 - Shift));
+    int64_t Addend = FullImmVal - (AddrA - AddrB);
+
+    // addend = Encoded - Expected
+    //        = Encoded - (AddrA - AddrB)
+
+    DEBUG(dbgs() << "Found SECTDIFF: AddrA: " << AddrA << ", AddrB: " << AddrB
+                 << ", Addend: " << Addend << ", SectionA ID: " << SectionAID
+                 << ", SectionAOffset: " << SectionAOffset
+                 << ", SectionB ID: " << SectionBID
+                 << ", SectionBOffset: " << SectionBOffset << "\n");
+    RelocationEntry R(SectionID, Offset, RelocType, Addend, SectionAID,
+                      SectionAOffset, SectionBID, SectionBOffset, IsPCRel,
+                      HalfDiffKindBits);
+
+    addRelocationForSection(R, SectionAID);
+    addRelocationForSection(R, SectionBID);
+
+    return ++RelI;
+  }
+
 };
 }