From 35fdeb7b373e416ff00c54abef12e786963af725 Mon Sep 17 00:00:00 2001 From: Jim Grosbach Date: Fri, 18 Mar 2011 18:54:32 +0000 Subject: [PATCH] Add llvm-rtdyld support for loading 32-bit code. Factor out the 64-bit specific bits into a helper function and add an equivalent that loads the 32-bit sections. This allows using llvm-rtdyld on ARM. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127892 91177308-0d34-0410-b5e6-96231b3b80d8 --- tools/llvm-rtdyld/llvm-rtdyld.cpp | 224 +++++++++++++++++++++--------- 1 file changed, 158 insertions(+), 66 deletions(-) diff --git a/tools/llvm-rtdyld/llvm-rtdyld.cpp b/tools/llvm-rtdyld/llvm-rtdyld.cpp index 42b6f633f10..6de5742a6a3 100644 --- a/tools/llvm-rtdyld/llvm-rtdyld.cpp +++ b/tools/llvm-rtdyld/llvm-rtdyld.cpp @@ -51,6 +51,157 @@ static int Error(const Twine &Msg) { } /* *** */ +static bool +loadSegment32(const MachOObject *Obj, + sys::MemoryBlock &Data, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC, + StringMap &SymbolTable) { + InMemoryStruct Segment32LC; + Obj->ReadSegmentLoadCommand(*SegmentLCI, Segment32LC); + if (!Segment32LC) + return Error("unable to load segment load command"); + + // Map the segment into memory. + std::string ErrorStr; + Data = sys::Memory::AllocateRWX(Segment32LC->VMSize, 0, &ErrorStr); + if (!Data.base()) + return Error("unable to allocate memory block: '" + ErrorStr + "'"); + memcpy(Data.base(), Obj->getData(Segment32LC->FileOffset, + Segment32LC->FileSize).data(), + Segment32LC->FileSize); + memset((char*)Data.base() + Segment32LC->FileSize, 0, + Segment32LC->VMSize - Segment32LC->FileSize); + + // Bind the section indices to address. + void **SectionBases = new void*[Segment32LC->NumSections]; + for (unsigned i = 0; i != Segment32LC->NumSections; ++i) { + InMemoryStruct Sect; + Obj->ReadSection(*SegmentLCI, i, Sect); + if (!Sect) + return Error("unable to load section: '" + Twine(i) + "'"); + + // FIXME: We don't support relocations yet. + if (Sect->NumRelocationTableEntries != 0) + return Error("not yet implemented: relocations!"); + + // FIXME: Improve check. + if (Sect->Flags != 0x80000400) + return Error("unsupported section type!"); + + SectionBases[i] = (char*) Data.base() + Sect->Address; + } + + // Bind all the symbols to address. + for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { + InMemoryStruct STE; + Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE); + if (!STE) + return Error("unable to read symbol: '" + Twine(i) + "'"); + if (STE->SectionIndex == 0) + return Error("unexpected undefined symbol!"); + + unsigned Index = STE->SectionIndex - 1; + if (Index >= Segment32LC->NumSections) + return Error("invalid section index for symbol: '" + Twine() + "'"); + + // Get the symbol name. + StringRef Name = Obj->getStringAtIndex(STE->StringIndex); + + // Get the section base address. + void *SectionBase = SectionBases[Index]; + + // Get the symbol address. + void *Address = (char*) SectionBase + STE->Value; + + // FIXME: Check the symbol type and flags. + if (STE->Type != 0xF) + return Error("unexpected symbol type!"); + if (STE->Flags != 0x0) + return Error("unexpected symbol type!"); + + SymbolTable[Name] = Address; + } + + delete SectionBases; + return false; +} + +static bool +loadSegment64(const MachOObject *Obj, + sys::MemoryBlock &Data, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC, + StringMap &SymbolTable) { + InMemoryStruct Segment64LC; + Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC); + if (!Segment64LC) + return Error("unable to load segment load command"); + + // Map the segment into memory. + std::string ErrorStr; + Data = sys::Memory::AllocateRWX(Segment64LC->VMSize, 0, &ErrorStr); + if (!Data.base()) + return Error("unable to allocate memory block: '" + ErrorStr + "'"); + memcpy(Data.base(), Obj->getData(Segment64LC->FileOffset, + Segment64LC->FileSize).data(), + Segment64LC->FileSize); + memset((char*)Data.base() + Segment64LC->FileSize, 0, + Segment64LC->VMSize - Segment64LC->FileSize); + + // Bind the section indices to address. + void **SectionBases = new void*[Segment64LC->NumSections]; + for (unsigned i = 0; i != Segment64LC->NumSections; ++i) { + InMemoryStruct Sect; + Obj->ReadSection64(*SegmentLCI, i, Sect); + if (!Sect) + return Error("unable to load section: '" + Twine(i) + "'"); + + // FIXME: We don't support relocations yet. + if (Sect->NumRelocationTableEntries != 0) + return Error("not yet implemented: relocations!"); + + // FIXME: Improve check. + if (Sect->Flags != 0x80000400) + return Error("unsupported section type!"); + + SectionBases[i] = (char*) Data.base() + Sect->Address; + } + + // Bind all the symbols to address. + for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { + InMemoryStruct STE; + Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE); + if (!STE) + return Error("unable to read symbol: '" + Twine(i) + "'"); + if (STE->SectionIndex == 0) + return Error("unexpected undefined symbol!"); + + unsigned Index = STE->SectionIndex - 1; + if (Index >= Segment64LC->NumSections) + return Error("invalid section index for symbol: '" + Twine() + "'"); + + // Get the symbol name. + StringRef Name = Obj->getStringAtIndex(STE->StringIndex); + + // Get the section base address. + void *SectionBase = SectionBases[Index]; + + // Get the symbol address. + void *Address = (char*) SectionBase + STE->Value; + + // FIXME: Check the symbol type and flags. + if (STE->Type != 0xF) + return Error("unexpected symbol type!"); + if (STE->Flags != 0x0) + return Error("unexpected symbol type!"); + + SymbolTable[Name] = Address; + } + + delete SectionBases; + return false; +} static int executeInput() { // Load the input memory buffer. @@ -122,73 +273,14 @@ static int executeInput() { } // Load the segment load command. - if (SegmentLCI->Command.Type != macho::LCT_Segment64) - return Error("Segment32 not yet implemented!"); - InMemoryStruct Segment64LC; - Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC); - if (!Segment64LC) - return Error("unable to load segment load command"); - - // Map the segment into memory. - sys::MemoryBlock Data = sys::Memory::AllocateRWX(Segment64LC->VMSize, - 0, &ErrorStr); - if (!Data.base()) - return Error("unable to allocate memory block: '" + ErrorStr + "'"); - memcpy(Data.base(), Obj->getData(Segment64LC->FileOffset, - Segment64LC->FileSize).data(), - Segment64LC->FileSize); - memset((char*)Data.base() + Segment64LC->FileSize, 0, - Segment64LC->VMSize - Segment64LC->FileSize); - - // Bind the section indices to address. - void **SectionBases = new void*[Segment64LC->NumSections]; - for (unsigned i = 0; i != Segment64LC->NumSections; ++i) { - InMemoryStruct Sect; - Obj->ReadSection64(*SegmentLCI, i, Sect); - if (!Sect) - return Error("unable to load section: '" + Twine(i) + "'"); - - // FIXME: We don't support relocations yet. - if (Sect->NumRelocationTableEntries != 0) - return Error("not yet implemented: relocations!"); - - // FIXME: Improve check. - if (Sect->Flags != 0x80000400) - return Error("unsupported section type!"); - - SectionBases[i] = (char*) Data.base() + Sect->Address; - } - - // Bind all the symbols to address. + sys::MemoryBlock Data; StringMap SymbolTable; - for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { - InMemoryStruct STE; - Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE); - if (!STE) - return Error("unable to read symbol: '" + Twine(i) + "'"); - if (STE->SectionIndex == 0) - return Error("unexpected undefined symbol!"); - - unsigned Index = STE->SectionIndex - 1; - if (Index >= Segment64LC->NumSections) - return Error("invalid section index for symbol: '" + Twine() + "'"); - - // Get the symbol name. - StringRef Name = Obj->getStringAtIndex(STE->StringIndex); - - // Get the section base address. - void *SectionBase = SectionBases[Index]; - - // Get the symbol address. - void *Address = (char*) SectionBase + STE->Value; - - // FIXME: Check the symbol type and flags. - if (STE->Type != 0xF) - return Error("unexpected symbol type!"); - if (STE->Flags != 0x0) - return Error("unexpected symbol type!"); - - SymbolTable[Name] = Address; + if (SegmentLCI->Command.Type == macho::LCT_Segment) { + if (loadSegment32(Obj.get(), Data, SegmentLCI, SymtabLC, SymbolTable)) + return true; + } else { + if (loadSegment64(Obj.get(), Data, SegmentLCI, SymtabLC, SymbolTable)) + return true; } // Get the address of "_main".