[llvm-commits] [llvm] r135037 - in /llvm/trunk: include/llvm/ExecutionEngine/RuntimeDyld.h lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
Danil Malyshev
dmalyshev at accesssoftek.com
Wed Jul 13 00:57:59 PDT 2011
Author: danil
Date: Wed Jul 13 02:57:58 2011
New Revision: 135037
URL: http://llvm.org/viewvc/llvm-project?rev=135037&view=rev
Log:
Add to RuntimeDyld support different object formats
Added:
llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
Modified:
llvm/trunk/include/llvm/ExecutionEngine/RuntimeDyld.h
llvm/trunk/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt
llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
Modified: llvm/trunk/include/llvm/ExecutionEngine/RuntimeDyld.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/ExecutionEngine/RuntimeDyld.h?rev=135037&r1=135036&r2=135037&view=diff
==============================================================================
--- llvm/trunk/include/llvm/ExecutionEngine/RuntimeDyld.h (original)
+++ llvm/trunk/include/llvm/ExecutionEngine/RuntimeDyld.h Wed Jul 13 02:57:58 2011
@@ -53,6 +53,7 @@
// RuntimeDyldImpl is the actual class. RuntimeDyld is just the public
// interface.
RuntimeDyldImpl *Dyld;
+ RTDyldMemoryManager *MM;
public:
RuntimeDyld(RTDyldMemoryManager*);
~RuntimeDyld();
Modified: llvm/trunk/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt?rev=135037&r1=135036&r2=135037&view=diff
==============================================================================
--- llvm/trunk/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt (original)
+++ llvm/trunk/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt Wed Jul 13 02:57:58 2011
@@ -1,3 +1,4 @@
add_llvm_library(LLVMRuntimeDyld
RuntimeDyld.cpp
+ RuntimeDyldMachO.cpp
)
Modified: llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp?rev=135037&r1=135036&r2=135037&view=diff
==============================================================================
--- llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp (original)
+++ llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp Wed Jul 13 02:57:58 2011
@@ -1,4 +1,4 @@
-//===-- RuntimeDyld.h - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
+//===-- RuntimeDyld.cpp - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
@@ -12,118 +12,15 @@
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "dyld"
-#include "llvm/ADT/OwningPtr.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringMap.h"
-#include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/ADT/Twine.h"
-#include "llvm/ExecutionEngine/RuntimeDyld.h"
-#include "llvm/Object/MachOObject.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/Format.h"
-#include "llvm/Support/Memory.h"
-#include "llvm/Support/MemoryBuffer.h"
-#include "llvm/Support/system_error.h"
-#include "llvm/Support/raw_ostream.h"
+#include "RuntimeDyldImpl.h"
using namespace llvm;
using namespace llvm::object;
// Empty out-of-line virtual destructor as the key function.
RTDyldMemoryManager::~RTDyldMemoryManager() {}
+RuntimeDyldImpl::~RuntimeDyldImpl() {}
namespace llvm {
-class RuntimeDyldImpl {
- unsigned CPUType;
- unsigned CPUSubtype;
-
- // The MemoryManager to load objects into.
- RTDyldMemoryManager *MemMgr;
-
- // FIXME: This all assumes we're dealing with external symbols for anything
- // explicitly referenced. I.e., we can index by name and things
- // will work out. In practice, this may not be the case, so we
- // should find a way to effectively generalize.
-
- // For each function, we have a MemoryBlock of it's instruction data.
- StringMap<sys::MemoryBlock> Functions;
-
- // Master symbol table. As modules are loaded and external symbols are
- // resolved, their addresses are stored here.
- StringMap<uint8_t*> SymbolTable;
-
- // 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.
- struct RelocationEntry {
- std::string Target; // Object this relocation is contained in.
- uint64_t Offset; // Offset into the object 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.
- bool isResolved; // Has this relocation been resolved previously?
-
- RelocationEntry(StringRef t, uint64_t offset, uint32_t data, int64_t addend)
- : Target(t), Offset(offset), Data(data), Addend(addend),
- isResolved(false) {}
- };
- typedef SmallVector<RelocationEntry, 4> RelocationList;
- StringMap<RelocationList> Relocations;
-
- // FIXME: Also keep a map of all the relocations contained in an object. Use
- // this to dynamically answer whether all of the relocations in it have
- // been resolved or not.
-
- bool HasError;
- std::string ErrorStr;
-
- // Set the error state and record an error string.
- bool Error(const Twine &Msg) {
- ErrorStr = Msg.str();
- HasError = true;
- return true;
- }
-
- void extractFunction(StringRef Name, uint8_t *StartAddress,
- uint8_t *EndAddress);
- bool resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
- unsigned Type, unsigned Size);
- bool resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
- unsigned Type, unsigned Size);
- bool resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
- unsigned Type, unsigned Size);
-
- 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);
-
-public:
- RuntimeDyldImpl(RTDyldMemoryManager *mm) : MemMgr(mm), HasError(false) {}
-
- bool loadObject(MemoryBuffer *InputBuffer);
-
- void *getSymbolAddress(StringRef Name) {
- // FIXME: Just look up as a function for now. Overly simple of course.
- // Work in progress.
- return SymbolTable.lookup(Name);
- }
-
- void resolveRelocations();
-
- void reassignSymbolAddress(StringRef Name, uint8_t *Addr);
-
- // Is the linker in an error state?
- bool hasError() { return HasError; }
-
- // Mark the error condition as handled and continue.
- void clearError() { HasError = false; }
-
- // Get the error message.
- StringRef getErrorString() { return ErrorStr; }
-};
void RuntimeDyldImpl::extractFunction(StringRef Name, uint8_t *StartAddress,
uint8_t *EndAddress) {
@@ -144,472 +41,6 @@
DEBUG(dbgs() << " allocated to [" << Mem << ", " << Mem + Size << "]\n");
}
-bool RuntimeDyldImpl::
-resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
- unsigned Type, unsigned Size) {
- // This just dispatches to the proper target specific routine.
- switch (CPUType) {
- default: assert(0 && "Unsupported CPU type!");
- case mach::CTM_x86_64:
- return resolveX86_64Relocation((uintptr_t)Address, (uintptr_t)Value,
- isPCRel, Type, Size);
- case mach::CTM_ARM:
- return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value,
- isPCRel, Type, Size);
- }
- llvm_unreachable("");
-}
-
-bool RuntimeDyldImpl::
-resolveX86_64Relocation(uintptr_t Address, uintptr_t Value,
- bool isPCRel, unsigned Type,
- unsigned Size) {
- // If the relocation is PC-relative, the value to be encoded is the
- // pointer difference.
- if (isPCRel)
- // FIXME: It seems this value needs to be adjusted by 4 for an effective PC
- // address. Is that expected? Only for branches, perhaps?
- Value -= Address + 4;
-
- switch(Type) {
- default:
- llvm_unreachable("Invalid relocation type!");
- case macho::RIT_X86_64_Unsigned:
- case macho::RIT_X86_64_Branch: {
- // Mask in the target value a byte at a time (we don't have an alignment
- // guarantee for the target address, so this is safest).
- uint8_t *p = (uint8_t*)Address;
- for (unsigned i = 0; i < Size; ++i) {
- *p++ = (uint8_t)Value;
- Value >>= 8;
- }
- return false;
- }
- case macho::RIT_X86_64_Signed:
- case macho::RIT_X86_64_GOTLoad:
- case macho::RIT_X86_64_GOT:
- case macho::RIT_X86_64_Subtractor:
- case macho::RIT_X86_64_Signed1:
- case macho::RIT_X86_64_Signed2:
- case macho::RIT_X86_64_Signed4:
- case macho::RIT_X86_64_TLV:
- return Error("Relocation type not implemented yet!");
- }
- return false;
-}
-
-bool RuntimeDyldImpl::resolveARMRelocation(uintptr_t Address, uintptr_t Value,
- bool isPCRel, unsigned Type,
- unsigned Size) {
- // If the relocation is PC-relative, the value to be encoded is the
- // pointer difference.
- if (isPCRel) {
- Value -= Address;
- // ARM PCRel relocations have an effective-PC offset of two instructions
- // (four bytes in Thumb mode, 8 bytes in ARM mode).
- // FIXME: For now, assume ARM mode.
- Value -= 8;
- }
-
- switch(Type) {
- default:
- llvm_unreachable("Invalid relocation type!");
- case macho::RIT_Vanilla: {
- llvm_unreachable("Invalid relocation type!");
- // Mask in the target value a byte at a time (we don't have an alignment
- // guarantee for the target address, so this is safest).
- uint8_t *p = (uint8_t*)Address;
- for (unsigned i = 0; i < Size; ++i) {
- *p++ = (uint8_t)Value;
- Value >>= 8;
- }
- break;
- }
- case macho::RIT_ARM_Branch24Bit: {
- // 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*)Address;
- // The low two bits of the value are not encoded.
- Value >>= 2;
- // Mask the value to 24 bits.
- Value &= 0xffffff;
- // FIXME: If the destination is a Thumb function (and the instruction
- // is a non-predicated BL instruction), we need to change it to a BLX
- // instruction instead.
-
- // Insert the value into the instruction.
- *p = (*p & ~0xffffff) | Value;
- break;
- }
- case macho::RIT_ARM_ThumbBranch22Bit:
- case macho::RIT_ARM_ThumbBranch32Bit:
- case macho::RIT_ARM_Half:
- case macho::RIT_ARM_HalfDifference:
- case macho::RIT_Pair:
- case macho::RIT_Difference:
- case macho::RIT_ARM_LocalDifference:
- case macho::RIT_ARM_PreboundLazyPointer:
- return Error("Relocation type not implemented yet!");
- }
- return false;
-}
-
-bool RuntimeDyldImpl::
-loadSegment32(const MachOObject *Obj,
- const MachOObject::LoadCommandInfo *SegmentLCI,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
- InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
- Obj->ReadSegmentLoadCommand(*SegmentLCI, SegmentLC);
- if (!SegmentLC)
- return Error("unable to load segment load command");
-
- for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
- InMemoryStruct<macho::Section> Sect;
- Obj->ReadSection(*SegmentLCI, SectNum, Sect);
- if (!Sect)
- return Error("unable to load section: '" + Twine(SectNum) + "'");
-
- // FIXME: For the time being, we're only loading text segments.
- if (Sect->Flags != 0x80000400)
- continue;
-
- // Address and names of symbols in the section.
- typedef std::pair<uint64_t, StringRef> SymbolEntry;
- SmallVector<SymbolEntry, 64> Symbols;
- // Index of all the names, in this section or not. Used when we're
- // dealing with relocation entries.
- SmallVector<StringRef, 64> SymbolNames;
- for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
- InMemoryStruct<macho::SymbolTableEntry> STE;
- Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE);
- if (!STE)
- return Error("unable to read symbol: '" + Twine(i) + "'");
- if (STE->SectionIndex > SegmentLC->NumSections)
- return Error("invalid section index for symbol: '" + Twine(i) + "'");
- // Get the symbol name.
- StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
- SymbolNames.push_back(Name);
-
- // Just skip symbols not defined in this section.
- if ((unsigned)STE->SectionIndex - 1 != SectNum)
- continue;
-
- // FIXME: Check the symbol type and flags.
- if (STE->Type != 0xF) // external, defined in this section.
- continue;
- // Flags == 0x8 marks a thumb function for ARM, which is fine as it
- // doesn't require any special handling here.
- if (STE->Flags != 0x0 && STE->Flags != 0x8)
- continue;
-
- // Remember the symbol.
- Symbols.push_back(SymbolEntry(STE->Value, Name));
-
- DEBUG(dbgs() << "Function sym: '" << Name << "' @ " <<
- (Sect->Address + STE->Value) << "\n");
- }
- // Sort the symbols by address, just in case they didn't come in that way.
- array_pod_sort(Symbols.begin(), Symbols.end());
-
- // If there weren't any functions (odd, but just in case...)
- if (!Symbols.size())
- continue;
-
- // Extract the function data.
- uint8_t *Base = (uint8_t*)Obj->getData(SegmentLC->FileOffset,
- SegmentLC->FileSize).data();
- for (unsigned i = 0, e = Symbols.size() - 1; i != e; ++i) {
- uint64_t StartOffset = Sect->Address + Symbols[i].first;
- uint64_t EndOffset = Symbols[i + 1].first - 1;
- DEBUG(dbgs() << "Extracting function: " << Symbols[i].second
- << " from [" << StartOffset << ", " << EndOffset << "]\n");
- extractFunction(Symbols[i].second, Base + StartOffset, Base + EndOffset);
- }
- // The last symbol we do after since the end address is calculated
- // differently because there is no next symbol to reference.
- uint64_t StartOffset = Symbols[Symbols.size() - 1].first;
- uint64_t EndOffset = Sect->Size - 1;
- DEBUG(dbgs() << "Extracting function: " << Symbols[Symbols.size()-1].second
- << " from [" << StartOffset << ", " << EndOffset << "]\n");
- extractFunction(Symbols[Symbols.size()-1].second,
- Base + StartOffset, Base + EndOffset);
-
- // Now extract the relocation information for each function and process it.
- for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) {
- InMemoryStruct<macho::RelocationEntry> RE;
- Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE);
- if (RE->Word0 & macho::RF_Scattered)
- return Error("NOT YET IMPLEMENTED: scattered relocations.");
- // Word0 of the relocation is the offset into the section where the
- // relocation should be applied. We need to translate that into an
- // offset into a function since that's our atom.
- uint32_t Offset = RE->Word0;
- // Look for the function containing the address. This is used for JIT
- // code, so the number of functions in section is almost always going
- // to be very small (usually just one), so until we have use cases
- // where that's not true, just use a trivial linear search.
- unsigned SymbolNum;
- unsigned NumSymbols = Symbols.size();
- assert(NumSymbols > 0 && Symbols[0].first <= Offset &&
- "No symbol containing relocation!");
- for (SymbolNum = 0; SymbolNum < NumSymbols - 1; ++SymbolNum)
- if (Symbols[SymbolNum + 1].first > Offset)
- break;
- // Adjust the offset to be relative to the symbol.
- Offset -= Symbols[SymbolNum].first;
- // Get the name of the symbol containing the relocation.
- StringRef TargetName = SymbolNames[SymbolNum];
-
- bool isExtern = (RE->Word1 >> 27) & 1;
- // Figure out the source symbol of the relocation. If isExtern is true,
- // this relocation references the symbol table, otherwise it references
- // a section in the same object, numbered from 1 through NumSections
- // (SectionBases is [0, NumSections-1]).
- // FIXME: Some targets (ARM) use internal relocations even for
- // externally visible symbols, if the definition is in the same
- // file as the reference. We need to convert those back to by-name
- // references. We can resolve the address based on the section
- // offset and see if we have a symbol at that address. If we do,
- // use that; otherwise, puke.
- if (!isExtern)
- return Error("Internal relocations not supported.");
- uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value
- StringRef SourceName = SymbolNames[SourceNum];
-
- // FIXME: Get the relocation addend from the target address.
-
- // Now store the relocation information. Associate it with the source
- // symbol.
- Relocations[SourceName].push_back(RelocationEntry(TargetName,
- Offset,
- RE->Word1,
- 0 /*Addend*/));
- DEBUG(dbgs() << "Relocation at '" << TargetName << "' + " << Offset
- << " from '" << SourceName << "(Word1: "
- << format("0x%x", RE->Word1) << ")\n");
- }
- }
- return false;
-}
-
-
-bool RuntimeDyldImpl::
-loadSegment64(const MachOObject *Obj,
- const MachOObject::LoadCommandInfo *SegmentLCI,
- const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
- InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
- Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC);
- if (!Segment64LC)
- return Error("unable to load segment load command");
-
- for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) {
- InMemoryStruct<macho::Section64> Sect;
- Obj->ReadSection64(*SegmentLCI, SectNum, Sect);
- if (!Sect)
- return Error("unable to load section: '" + Twine(SectNum) + "'");
-
- // FIXME: For the time being, we're only loading text segments.
- if (Sect->Flags != 0x80000400)
- continue;
-
- // Address and names of symbols in the section.
- typedef std::pair<uint64_t, StringRef> SymbolEntry;
- SmallVector<SymbolEntry, 64> Symbols;
- // Index of all the names, in this section or not. Used when we're
- // dealing with relocation entries.
- SmallVector<StringRef, 64> SymbolNames;
- for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
- InMemoryStruct<macho::Symbol64TableEntry> STE;
- Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
- if (!STE)
- return Error("unable to read symbol: '" + Twine(i) + "'");
- if (STE->SectionIndex > Segment64LC->NumSections)
- return Error("invalid section index for symbol: '" + Twine(i) + "'");
- // Get the symbol name.
- StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
- SymbolNames.push_back(Name);
-
- // Just skip symbols not defined in this section.
- if ((unsigned)STE->SectionIndex - 1 != SectNum)
- continue;
-
- // FIXME: Check the symbol type and flags.
- if (STE->Type != 0xF) // external, defined in this section.
- continue;
- if (STE->Flags != 0x0)
- continue;
-
- // Remember the symbol.
- Symbols.push_back(SymbolEntry(STE->Value, Name));
-
- DEBUG(dbgs() << "Function sym: '" << Name << "' @ " <<
- (Sect->Address + STE->Value) << "\n");
- }
- // Sort the symbols by address, just in case they didn't come in that way.
- array_pod_sort(Symbols.begin(), Symbols.end());
-
- // If there weren't any functions (odd, but just in case...)
- if (!Symbols.size())
- continue;
-
- // Extract the function data.
- uint8_t *Base = (uint8_t*)Obj->getData(Segment64LC->FileOffset,
- Segment64LC->FileSize).data();
- for (unsigned i = 0, e = Symbols.size() - 1; i != e; ++i) {
- uint64_t StartOffset = Sect->Address + Symbols[i].first;
- uint64_t EndOffset = Symbols[i + 1].first - 1;
- DEBUG(dbgs() << "Extracting function: " << Symbols[i].second
- << " from [" << StartOffset << ", " << EndOffset << "]\n");
- extractFunction(Symbols[i].second, Base + StartOffset, Base + EndOffset);
- }
- // The last symbol we do after since the end address is calculated
- // differently because there is no next symbol to reference.
- uint64_t StartOffset = Symbols[Symbols.size() - 1].first;
- uint64_t EndOffset = Sect->Size - 1;
- DEBUG(dbgs() << "Extracting function: " << Symbols[Symbols.size()-1].second
- << " from [" << StartOffset << ", " << EndOffset << "]\n");
- extractFunction(Symbols[Symbols.size()-1].second,
- Base + StartOffset, Base + EndOffset);
-
- // Now extract the relocation information for each function and process it.
- for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) {
- InMemoryStruct<macho::RelocationEntry> RE;
- Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE);
- if (RE->Word0 & macho::RF_Scattered)
- return Error("NOT YET IMPLEMENTED: scattered relocations.");
- // Word0 of the relocation is the offset into the section where the
- // relocation should be applied. We need to translate that into an
- // offset into a function since that's our atom.
- uint32_t Offset = RE->Word0;
- // Look for the function containing the address. This is used for JIT
- // code, so the number of functions in section is almost always going
- // to be very small (usually just one), so until we have use cases
- // where that's not true, just use a trivial linear search.
- unsigned SymbolNum;
- unsigned NumSymbols = Symbols.size();
- assert(NumSymbols > 0 && Symbols[0].first <= Offset &&
- "No symbol containing relocation!");
- for (SymbolNum = 0; SymbolNum < NumSymbols - 1; ++SymbolNum)
- if (Symbols[SymbolNum + 1].first > Offset)
- break;
- // Adjust the offset to be relative to the symbol.
- Offset -= Symbols[SymbolNum].first;
- // Get the name of the symbol containing the relocation.
- StringRef TargetName = SymbolNames[SymbolNum];
-
- bool isExtern = (RE->Word1 >> 27) & 1;
- // Figure out the source symbol of the relocation. If isExtern is true,
- // this relocation references the symbol table, otherwise it references
- // a section in the same object, numbered from 1 through NumSections
- // (SectionBases is [0, NumSections-1]).
- if (!isExtern)
- return Error("Internal relocations not supported.");
- uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value
- StringRef SourceName = SymbolNames[SourceNum];
-
- // FIXME: Get the relocation addend from the target address.
-
- // Now store the relocation information. Associate it with the source
- // symbol.
- Relocations[SourceName].push_back(RelocationEntry(TargetName,
- Offset,
- RE->Word1,
- 0 /*Addend*/));
- DEBUG(dbgs() << "Relocation at '" << TargetName << "' + " << Offset
- << " from '" << SourceName << "(Word1: "
- << format("0x%x", RE->Word1) << ")\n");
- }
- }
- return false;
-}
-
-bool RuntimeDyldImpl::loadObject(MemoryBuffer *InputBuffer) {
- // If the linker is in an error state, don't do anything.
- if (hasError())
- return true;
- // Load the Mach-O wrapper object.
- std::string ErrorStr;
- OwningPtr<MachOObject> Obj(
- MachOObject::LoadFromBuffer(InputBuffer, &ErrorStr));
- if (!Obj)
- return Error("unable to load object: '" + ErrorStr + "'");
-
- // Get the CPU type information from the header.
- const macho::Header &Header = Obj->getHeader();
-
- // FIXME: Error checking that the loaded object is compatible with
- // the system we're running on.
- CPUType = Header.CPUType;
- CPUSubtype = Header.CPUSubtype;
-
- // Validate that the load commands match what we expect.
- const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0,
- *DysymtabLCI = 0;
- for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
- const MachOObject::LoadCommandInfo &LCI = Obj->getLoadCommandInfo(i);
- switch (LCI.Command.Type) {
- case macho::LCT_Segment:
- case macho::LCT_Segment64:
- if (SegmentLCI)
- return Error("unexpected input object (multiple segments)");
- SegmentLCI = &LCI;
- break;
- case macho::LCT_Symtab:
- if (SymtabLCI)
- return Error("unexpected input object (multiple symbol tables)");
- SymtabLCI = &LCI;
- break;
- case macho::LCT_Dysymtab:
- if (DysymtabLCI)
- return Error("unexpected input object (multiple symbol tables)");
- DysymtabLCI = &LCI;
- break;
- default:
- return Error("unexpected input object (unexpected load command");
- }
- }
-
- if (!SymtabLCI)
- return Error("no symbol table found in object");
- if (!SegmentLCI)
- return Error("no symbol table found in object");
-
- // Read and register the symbol table data.
- InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
- Obj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
- if (!SymtabLC)
- return Error("unable to load symbol table load command");
- Obj->RegisterStringTable(*SymtabLC);
-
- // Read the dynamic link-edit information, if present (not present in static
- // objects).
- if (DysymtabLCI) {
- InMemoryStruct<macho::DysymtabLoadCommand> DysymtabLC;
- Obj->ReadDysymtabLoadCommand(*DysymtabLCI, DysymtabLC);
- if (!DysymtabLC)
- return Error("unable to load dynamic link-exit load command");
-
- // FIXME: We don't support anything interesting yet.
-// if (DysymtabLC->LocalSymbolsIndex != 0)
-// return Error("NOT YET IMPLEMENTED: local symbol entries");
-// if (DysymtabLC->ExternalSymbolsIndex != 0)
-// return Error("NOT YET IMPLEMENTED: non-external symbol entries");
-// if (DysymtabLC->UndefinedSymbolsIndex != SymtabLC->NumSymbolTableEntries)
-// return Error("NOT YET IMPLEMENTED: undefined symbol entries");
- }
-
- // Load the segment load command.
- if (SegmentLCI->Command.Type == macho::LCT_Segment) {
- if (loadSegment32(Obj.get(), SegmentLCI, SymtabLC))
- return true;
- } else {
- if (loadSegment64(Obj.get(), SegmentLCI, SymtabLC))
- return true;
- }
-
- return false;
-}
-
// Resolve the relocations for all symbols we currently know about.
void RuntimeDyldImpl::resolveRelocations() {
// Just iterate over the symbols in our symbol table and assign their
@@ -620,35 +51,11 @@
reassignSymbolAddress(i->getKey(), i->getValue());
}
-// Assign an address to a symbol name and resolve all the relocations
-// associated with it.
-void RuntimeDyldImpl::reassignSymbolAddress(StringRef Name, uint8_t *Addr) {
- // Assign the address in our symbol table.
- SymbolTable[Name] = Addr;
-
- RelocationList &Relocs = Relocations[Name];
- for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
- RelocationEntry &RE = Relocs[i];
- uint8_t *Target = SymbolTable[RE.Target] + RE.Offset;
- bool isPCRel = (RE.Data >> 24) & 1;
- unsigned Type = (RE.Data >> 28) & 0xf;
- unsigned Size = 1 << ((RE.Data >> 25) & 3);
-
- DEBUG(dbgs() << "Resolving relocation at '" << RE.Target
- << "' + " << RE.Offset << " (" << format("%p", Target) << ")"
- << " from '" << Name << " (" << format("%p", Addr) << ")"
- << "(" << (isPCRel ? "pcrel" : "absolute")
- << ", type: " << Type << ", Size: " << Size << ").\n");
-
- resolveRelocation(Target, Addr, isPCRel, Type, Size);
- RE.isResolved = true;
- }
-}
-
//===----------------------------------------------------------------------===//
// RuntimeDyld class implementation
-RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *MM) {
- Dyld = new RuntimeDyldImpl(MM);
+RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *mm) {
+ Dyld = 0;
+ MM = mm;
}
RuntimeDyld::~RuntimeDyld() {
@@ -656,6 +63,16 @@
}
bool RuntimeDyld::loadObject(MemoryBuffer *InputBuffer) {
+ if (!Dyld) {
+ if (RuntimeDyldMachO::isKnownFormat(InputBuffer))
+ Dyld = new RuntimeDyldMachO(MM);
+ else
+ report_fatal_error("Unknown object format!");
+ } else {
+ if(!Dyld->isCompatibleFormat(InputBuffer))
+ report_fatal_error("Incompatible object format!");
+ }
+
return Dyld->loadObject(InputBuffer);
}
Added: llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h?rev=135037&view=auto
==============================================================================
--- llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h (added)
+++ llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h Wed Jul 13 02:57:58 2011
@@ -0,0 +1,152 @@
+//===-- RuntimeDyldImpl.h - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Interface for the implementations of runtime dynamic linker facilities.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_RUNTIME_DYLD_IMPL_H
+#define LLVM_RUNTIME_DYLD_IMPL_H
+
+#include "llvm/ExecutionEngine/RuntimeDyld.h"
+#include "llvm/Object/MachOObject.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ExecutionEngine/ExecutionEngine.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/Memory.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/system_error.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+
+using namespace llvm;
+using namespace llvm::object;
+
+namespace llvm {
+class RuntimeDyldImpl {
+protected:
+ unsigned CPUType;
+ unsigned CPUSubtype;
+
+ // The MemoryManager to load objects into.
+ RTDyldMemoryManager *MemMgr;
+
+ // FIXME: This all assumes we're dealing with external symbols for anything
+ // explicitly referenced. I.e., we can index by name and things
+ // will work out. In practice, this may not be the case, so we
+ // should find a way to effectively generalize.
+
+ // For each function, we have a MemoryBlock of it's instruction data.
+ StringMap<sys::MemoryBlock> Functions;
+
+ // Master symbol table. As modules are loaded and external symbols are
+ // resolved, their addresses are stored here.
+ StringMap<uint8_t*> SymbolTable;
+
+ bool HasError;
+ std::string ErrorStr;
+
+ // Set the error state and record an error string.
+ bool Error(const Twine &Msg) {
+ ErrorStr = Msg.str();
+ HasError = true;
+ return true;
+ }
+
+ void extractFunction(StringRef Name, uint8_t *StartAddress,
+ uint8_t *EndAddress);
+
+public:
+ RuntimeDyldImpl(RTDyldMemoryManager *mm) : MemMgr(mm), HasError(false) {}
+
+ virtual ~RuntimeDyldImpl();
+
+ virtual bool loadObject(MemoryBuffer *InputBuffer) = 0;
+
+ void *getSymbolAddress(StringRef Name) {
+ // FIXME: Just look up as a function for now. Overly simple of course.
+ // Work in progress.
+ return SymbolTable.lookup(Name);
+ }
+
+ void resolveRelocations();
+
+ virtual void reassignSymbolAddress(StringRef Name, uint8_t *Addr) = 0;
+
+ // Is the linker in an error state?
+ bool hasError() { return HasError; }
+
+ // Mark the error condition as handled and continue.
+ void clearError() { HasError = false; }
+
+ // Get the error message.
+ StringRef getErrorString() { return ErrorStr; }
+
+ virtual bool isCompatibleFormat(const MemoryBuffer *InputBuffer) const = 0;
+};
+
+
+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.
+ struct RelocationEntry {
+ std::string Target; // Object this relocation is contained in.
+ uint64_t Offset; // Offset into the object 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.
+ bool isResolved; // Has this relocation been resolved previously?
+
+ RelocationEntry(StringRef t, uint64_t offset, uint32_t data, int64_t addend)
+ : Target(t), Offset(offset), Data(data), Addend(addend),
+ isResolved(false) {}
+ };
+ typedef SmallVector<RelocationEntry, 4> RelocationList;
+ StringMap<RelocationList> Relocations;
+
+ // FIXME: Also keep a map of all the relocations contained in an object. Use
+ // this to dynamically answer whether all of the relocations in it have
+ // been resolved or not.
+
+ bool resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
+ unsigned Type, unsigned Size);
+ bool resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
+ unsigned Type, unsigned Size);
+ bool resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
+ unsigned Type, unsigned Size);
+
+ 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);
+
+public:
+ RuntimeDyldMachO(RTDyldMemoryManager *mm) : RuntimeDyldImpl(mm) {}
+
+ bool loadObject(MemoryBuffer *InputBuffer);
+
+ void reassignSymbolAddress(StringRef Name, uint8_t *Addr);
+
+ static bool isKnownFormat(const MemoryBuffer *InputBuffer);
+
+ bool isCompatibleFormat(const MemoryBuffer *InputBuffer) const {
+ return isKnownFormat(InputBuffer);
+ };
+};
+
+} // end namespace llvm
+
+
+#endif
Added: llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp?rev=135037&view=auto
==============================================================================
--- llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp (added)
+++ llvm/trunk/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp Wed Jul 13 02:57:58 2011
@@ -0,0 +1,524 @@
+//===-- RuntimeDyldMachO.cpp - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Implementation of the MC-JIT runtime dynamic linker.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "dyld"
+#include "llvm/ADT/OwningPtr.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/STLExtras.h"
+#include "RuntimeDyldImpl.h"
+using namespace llvm;
+using namespace llvm::object;
+
+namespace llvm {
+
+bool RuntimeDyldMachO::
+resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
+ unsigned Type, unsigned Size) {
+ // This just dispatches to the proper target specific routine.
+ switch (CPUType) {
+ default: assert(0 && "Unsupported CPU type!");
+ case mach::CTM_x86_64:
+ return resolveX86_64Relocation((uintptr_t)Address, (uintptr_t)Value,
+ isPCRel, Type, Size);
+ case mach::CTM_ARM:
+ return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value,
+ isPCRel, Type, Size);
+ }
+ llvm_unreachable("");
+}
+
+bool RuntimeDyldMachO::
+resolveX86_64Relocation(uintptr_t Address, uintptr_t Value,
+ bool isPCRel, unsigned Type,
+ unsigned Size) {
+ // If the relocation is PC-relative, the value to be encoded is the
+ // pointer difference.
+ if (isPCRel)
+ // FIXME: It seems this value needs to be adjusted by 4 for an effective PC
+ // address. Is that expected? Only for branches, perhaps?
+ Value -= Address + 4;
+
+ switch(Type) {
+ default:
+ llvm_unreachable("Invalid relocation type!");
+ case macho::RIT_X86_64_Unsigned:
+ case macho::RIT_X86_64_Branch: {
+ // Mask in the target value a byte at a time (we don't have an alignment
+ // guarantee for the target address, so this is safest).
+ uint8_t *p = (uint8_t*)Address;
+ for (unsigned i = 0; i < Size; ++i) {
+ *p++ = (uint8_t)Value;
+ Value >>= 8;
+ }
+ return false;
+ }
+ case macho::RIT_X86_64_Signed:
+ case macho::RIT_X86_64_GOTLoad:
+ case macho::RIT_X86_64_GOT:
+ case macho::RIT_X86_64_Subtractor:
+ case macho::RIT_X86_64_Signed1:
+ case macho::RIT_X86_64_Signed2:
+ case macho::RIT_X86_64_Signed4:
+ case macho::RIT_X86_64_TLV:
+ return Error("Relocation type not implemented yet!");
+ }
+ return false;
+}
+
+bool RuntimeDyldMachO::resolveARMRelocation(uintptr_t Address, uintptr_t Value,
+ bool isPCRel, unsigned Type,
+ unsigned Size) {
+ // If the relocation is PC-relative, the value to be encoded is the
+ // pointer difference.
+ if (isPCRel) {
+ Value -= Address;
+ // ARM PCRel relocations have an effective-PC offset of two instructions
+ // (four bytes in Thumb mode, 8 bytes in ARM mode).
+ // FIXME: For now, assume ARM mode.
+ Value -= 8;
+ }
+
+ switch(Type) {
+ default:
+ llvm_unreachable("Invalid relocation type!");
+ case macho::RIT_Vanilla: {
+ llvm_unreachable("Invalid relocation type!");
+ // Mask in the target value a byte at a time (we don't have an alignment
+ // guarantee for the target address, so this is safest).
+ uint8_t *p = (uint8_t*)Address;
+ for (unsigned i = 0; i < Size; ++i) {
+ *p++ = (uint8_t)Value;
+ Value >>= 8;
+ }
+ break;
+ }
+ case macho::RIT_ARM_Branch24Bit: {
+ // 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*)Address;
+ // The low two bits of the value are not encoded.
+ Value >>= 2;
+ // Mask the value to 24 bits.
+ Value &= 0xffffff;
+ // FIXME: If the destination is a Thumb function (and the instruction
+ // is a non-predicated BL instruction), we need to change it to a BLX
+ // instruction instead.
+
+ // Insert the value into the instruction.
+ *p = (*p & ~0xffffff) | Value;
+ break;
+ }
+ case macho::RIT_ARM_ThumbBranch22Bit:
+ case macho::RIT_ARM_ThumbBranch32Bit:
+ case macho::RIT_ARM_Half:
+ case macho::RIT_ARM_HalfDifference:
+ case macho::RIT_Pair:
+ case macho::RIT_Difference:
+ case macho::RIT_ARM_LocalDifference:
+ case macho::RIT_ARM_PreboundLazyPointer:
+ return Error("Relocation type not implemented yet!");
+ }
+ return false;
+}
+
+bool RuntimeDyldMachO::
+loadSegment32(const MachOObject *Obj,
+ const MachOObject::LoadCommandInfo *SegmentLCI,
+ const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
+ InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
+ Obj->ReadSegmentLoadCommand(*SegmentLCI, SegmentLC);
+ if (!SegmentLC)
+ return Error("unable to load segment load command");
+
+ for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
+ InMemoryStruct<macho::Section> Sect;
+ Obj->ReadSection(*SegmentLCI, SectNum, Sect);
+ if (!Sect)
+ return Error("unable to load section: '" + Twine(SectNum) + "'");
+
+ // FIXME: For the time being, we're only loading text segments.
+ if (Sect->Flags != 0x80000400)
+ continue;
+
+ // Address and names of symbols in the section.
+ typedef std::pair<uint64_t, StringRef> SymbolEntry;
+ SmallVector<SymbolEntry, 64> Symbols;
+ // Index of all the names, in this section or not. Used when we're
+ // dealing with relocation entries.
+ SmallVector<StringRef, 64> SymbolNames;
+ for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
+ InMemoryStruct<macho::SymbolTableEntry> STE;
+ Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE);
+ if (!STE)
+ return Error("unable to read symbol: '" + Twine(i) + "'");
+ if (STE->SectionIndex > SegmentLC->NumSections)
+ return Error("invalid section index for symbol: '" + Twine(i) + "'");
+ // Get the symbol name.
+ StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
+ SymbolNames.push_back(Name);
+
+ // Just skip symbols not defined in this section.
+ if ((unsigned)STE->SectionIndex - 1 != SectNum)
+ continue;
+
+ // FIXME: Check the symbol type and flags.
+ if (STE->Type != 0xF) // external, defined in this section.
+ continue;
+ // Flags == 0x8 marks a thumb function for ARM, which is fine as it
+ // doesn't require any special handling here.
+ if (STE->Flags != 0x0 && STE->Flags != 0x8)
+ continue;
+
+ // Remember the symbol.
+ Symbols.push_back(SymbolEntry(STE->Value, Name));
+
+ DEBUG(dbgs() << "Function sym: '" << Name << "' @ " <<
+ (Sect->Address + STE->Value) << "\n");
+ }
+ // Sort the symbols by address, just in case they didn't come in that way.
+ array_pod_sort(Symbols.begin(), Symbols.end());
+
+ // If there weren't any functions (odd, but just in case...)
+ if (!Symbols.size())
+ continue;
+
+ // Extract the function data.
+ uint8_t *Base = (uint8_t*)Obj->getData(SegmentLC->FileOffset,
+ SegmentLC->FileSize).data();
+ for (unsigned i = 0, e = Symbols.size() - 1; i != e; ++i) {
+ uint64_t StartOffset = Sect->Address + Symbols[i].first;
+ uint64_t EndOffset = Symbols[i + 1].first - 1;
+ DEBUG(dbgs() << "Extracting function: " << Symbols[i].second
+ << " from [" << StartOffset << ", " << EndOffset << "]\n");
+ extractFunction(Symbols[i].second, Base + StartOffset, Base + EndOffset);
+ }
+ // The last symbol we do after since the end address is calculated
+ // differently because there is no next symbol to reference.
+ uint64_t StartOffset = Symbols[Symbols.size() - 1].first;
+ uint64_t EndOffset = Sect->Size - 1;
+ DEBUG(dbgs() << "Extracting function: " << Symbols[Symbols.size()-1].second
+ << " from [" << StartOffset << ", " << EndOffset << "]\n");
+ extractFunction(Symbols[Symbols.size()-1].second,
+ Base + StartOffset, Base + EndOffset);
+
+ // Now extract the relocation information for each function and process it.
+ for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) {
+ InMemoryStruct<macho::RelocationEntry> RE;
+ Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE);
+ if (RE->Word0 & macho::RF_Scattered)
+ return Error("NOT YET IMPLEMENTED: scattered relocations.");
+ // Word0 of the relocation is the offset into the section where the
+ // relocation should be applied. We need to translate that into an
+ // offset into a function since that's our atom.
+ uint32_t Offset = RE->Word0;
+ // Look for the function containing the address. This is used for JIT
+ // code, so the number of functions in section is almost always going
+ // to be very small (usually just one), so until we have use cases
+ // where that's not true, just use a trivial linear search.
+ unsigned SymbolNum;
+ unsigned NumSymbols = Symbols.size();
+ assert(NumSymbols > 0 && Symbols[0].first <= Offset &&
+ "No symbol containing relocation!");
+ for (SymbolNum = 0; SymbolNum < NumSymbols - 1; ++SymbolNum)
+ if (Symbols[SymbolNum + 1].first > Offset)
+ break;
+ // Adjust the offset to be relative to the symbol.
+ Offset -= Symbols[SymbolNum].first;
+ // Get the name of the symbol containing the relocation.
+ StringRef TargetName = SymbolNames[SymbolNum];
+
+ bool isExtern = (RE->Word1 >> 27) & 1;
+ // Figure out the source symbol of the relocation. If isExtern is true,
+ // this relocation references the symbol table, otherwise it references
+ // a section in the same object, numbered from 1 through NumSections
+ // (SectionBases is [0, NumSections-1]).
+ // FIXME: Some targets (ARM) use internal relocations even for
+ // externally visible symbols, if the definition is in the same
+ // file as the reference. We need to convert those back to by-name
+ // references. We can resolve the address based on the section
+ // offset and see if we have a symbol at that address. If we do,
+ // use that; otherwise, puke.
+ if (!isExtern)
+ return Error("Internal relocations not supported.");
+ uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value
+ StringRef SourceName = SymbolNames[SourceNum];
+
+ // FIXME: Get the relocation addend from the target address.
+
+ // Now store the relocation information. Associate it with the source
+ // symbol.
+ Relocations[SourceName].push_back(RelocationEntry(TargetName,
+ Offset,
+ RE->Word1,
+ 0 /*Addend*/));
+ DEBUG(dbgs() << "Relocation at '" << TargetName << "' + " << Offset
+ << " from '" << SourceName << "(Word1: "
+ << format("0x%x", RE->Word1) << ")\n");
+ }
+ }
+ return false;
+}
+
+
+bool RuntimeDyldMachO::
+loadSegment64(const MachOObject *Obj,
+ const MachOObject::LoadCommandInfo *SegmentLCI,
+ const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
+ InMemoryStruct<macho::Segment64LoadCommand> Segment64LC;
+ Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC);
+ if (!Segment64LC)
+ return Error("unable to load segment load command");
+
+ for (unsigned SectNum = 0; SectNum != Segment64LC->NumSections; ++SectNum) {
+ InMemoryStruct<macho::Section64> Sect;
+ Obj->ReadSection64(*SegmentLCI, SectNum, Sect);
+ if (!Sect)
+ return Error("unable to load section: '" + Twine(SectNum) + "'");
+
+ // FIXME: For the time being, we're only loading text segments.
+ if (Sect->Flags != 0x80000400)
+ continue;
+
+ // Address and names of symbols in the section.
+ typedef std::pair<uint64_t, StringRef> SymbolEntry;
+ SmallVector<SymbolEntry, 64> Symbols;
+ // Index of all the names, in this section or not. Used when we're
+ // dealing with relocation entries.
+ SmallVector<StringRef, 64> SymbolNames;
+ for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
+ InMemoryStruct<macho::Symbol64TableEntry> STE;
+ Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE);
+ if (!STE)
+ return Error("unable to read symbol: '" + Twine(i) + "'");
+ if (STE->SectionIndex > Segment64LC->NumSections)
+ return Error("invalid section index for symbol: '" + Twine(i) + "'");
+ // Get the symbol name.
+ StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
+ SymbolNames.push_back(Name);
+
+ // Just skip symbols not defined in this section.
+ if ((unsigned)STE->SectionIndex - 1 != SectNum)
+ continue;
+
+ // FIXME: Check the symbol type and flags.
+ if (STE->Type != 0xF) // external, defined in this section.
+ continue;
+ if (STE->Flags != 0x0)
+ continue;
+
+ // Remember the symbol.
+ Symbols.push_back(SymbolEntry(STE->Value, Name));
+
+ DEBUG(dbgs() << "Function sym: '" << Name << "' @ " <<
+ (Sect->Address + STE->Value) << "\n");
+ }
+ // Sort the symbols by address, just in case they didn't come in that way.
+ array_pod_sort(Symbols.begin(), Symbols.end());
+
+ // If there weren't any functions (odd, but just in case...)
+ if (!Symbols.size())
+ continue;
+
+ // Extract the function data.
+ uint8_t *Base = (uint8_t*)Obj->getData(Segment64LC->FileOffset,
+ Segment64LC->FileSize).data();
+ for (unsigned i = 0, e = Symbols.size() - 1; i != e; ++i) {
+ uint64_t StartOffset = Sect->Address + Symbols[i].first;
+ uint64_t EndOffset = Symbols[i + 1].first - 1;
+ DEBUG(dbgs() << "Extracting function: " << Symbols[i].second
+ << " from [" << StartOffset << ", " << EndOffset << "]\n");
+ extractFunction(Symbols[i].second, Base + StartOffset, Base + EndOffset);
+ }
+ // The last symbol we do after since the end address is calculated
+ // differently because there is no next symbol to reference.
+ uint64_t StartOffset = Symbols[Symbols.size() - 1].first;
+ uint64_t EndOffset = Sect->Size - 1;
+ DEBUG(dbgs() << "Extracting function: " << Symbols[Symbols.size()-1].second
+ << " from [" << StartOffset << ", " << EndOffset << "]\n");
+ extractFunction(Symbols[Symbols.size()-1].second,
+ Base + StartOffset, Base + EndOffset);
+
+ // Now extract the relocation information for each function and process it.
+ for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) {
+ InMemoryStruct<macho::RelocationEntry> RE;
+ Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE);
+ if (RE->Word0 & macho::RF_Scattered)
+ return Error("NOT YET IMPLEMENTED: scattered relocations.");
+ // Word0 of the relocation is the offset into the section where the
+ // relocation should be applied. We need to translate that into an
+ // offset into a function since that's our atom.
+ uint32_t Offset = RE->Word0;
+ // Look for the function containing the address. This is used for JIT
+ // code, so the number of functions in section is almost always going
+ // to be very small (usually just one), so until we have use cases
+ // where that's not true, just use a trivial linear search.
+ unsigned SymbolNum;
+ unsigned NumSymbols = Symbols.size();
+ assert(NumSymbols > 0 && Symbols[0].first <= Offset &&
+ "No symbol containing relocation!");
+ for (SymbolNum = 0; SymbolNum < NumSymbols - 1; ++SymbolNum)
+ if (Symbols[SymbolNum + 1].first > Offset)
+ break;
+ // Adjust the offset to be relative to the symbol.
+ Offset -= Symbols[SymbolNum].first;
+ // Get the name of the symbol containing the relocation.
+ StringRef TargetName = SymbolNames[SymbolNum];
+
+ bool isExtern = (RE->Word1 >> 27) & 1;
+ // Figure out the source symbol of the relocation. If isExtern is true,
+ // this relocation references the symbol table, otherwise it references
+ // a section in the same object, numbered from 1 through NumSections
+ // (SectionBases is [0, NumSections-1]).
+ if (!isExtern)
+ return Error("Internal relocations not supported.");
+ uint32_t SourceNum = RE->Word1 & 0xffffff; // 24-bit value
+ StringRef SourceName = SymbolNames[SourceNum];
+
+ // FIXME: Get the relocation addend from the target address.
+
+ // Now store the relocation information. Associate it with the source
+ // symbol.
+ Relocations[SourceName].push_back(RelocationEntry(TargetName,
+ Offset,
+ RE->Word1,
+ 0 /*Addend*/));
+ DEBUG(dbgs() << "Relocation at '" << TargetName << "' + " << Offset
+ << " from '" << SourceName << "(Word1: "
+ << format("0x%x", RE->Word1) << ")\n");
+ }
+ }
+ return false;
+}
+
+bool RuntimeDyldMachO::loadObject(MemoryBuffer *InputBuffer) {
+ // If the linker is in an error state, don't do anything.
+ if (hasError())
+ return true;
+ // Load the Mach-O wrapper object.
+ std::string ErrorStr;
+ OwningPtr<MachOObject> Obj(
+ MachOObject::LoadFromBuffer(InputBuffer, &ErrorStr));
+ if (!Obj)
+ return Error("unable to load object: '" + ErrorStr + "'");
+
+ // Get the CPU type information from the header.
+ const macho::Header &Header = Obj->getHeader();
+
+ // FIXME: Error checking that the loaded object is compatible with
+ // the system we're running on.
+ CPUType = Header.CPUType;
+ CPUSubtype = Header.CPUSubtype;
+
+ // Validate that the load commands match what we expect.
+ const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0,
+ *DysymtabLCI = 0;
+ for (unsigned i = 0; i != Header.NumLoadCommands; ++i) {
+ const MachOObject::LoadCommandInfo &LCI = Obj->getLoadCommandInfo(i);
+ switch (LCI.Command.Type) {
+ case macho::LCT_Segment:
+ case macho::LCT_Segment64:
+ if (SegmentLCI)
+ return Error("unexpected input object (multiple segments)");
+ SegmentLCI = &LCI;
+ break;
+ case macho::LCT_Symtab:
+ if (SymtabLCI)
+ return Error("unexpected input object (multiple symbol tables)");
+ SymtabLCI = &LCI;
+ break;
+ case macho::LCT_Dysymtab:
+ if (DysymtabLCI)
+ return Error("unexpected input object (multiple symbol tables)");
+ DysymtabLCI = &LCI;
+ break;
+ default:
+ return Error("unexpected input object (unexpected load command");
+ }
+ }
+
+ if (!SymtabLCI)
+ return Error("no symbol table found in object");
+ if (!SegmentLCI)
+ return Error("no symbol table found in object");
+
+ // Read and register the symbol table data.
+ InMemoryStruct<macho::SymtabLoadCommand> SymtabLC;
+ Obj->ReadSymtabLoadCommand(*SymtabLCI, SymtabLC);
+ if (!SymtabLC)
+ return Error("unable to load symbol table load command");
+ Obj->RegisterStringTable(*SymtabLC);
+
+ // Read the dynamic link-edit information, if present (not present in static
+ // objects).
+ if (DysymtabLCI) {
+ InMemoryStruct<macho::DysymtabLoadCommand> DysymtabLC;
+ Obj->ReadDysymtabLoadCommand(*DysymtabLCI, DysymtabLC);
+ if (!DysymtabLC)
+ return Error("unable to load dynamic link-exit load command");
+
+ // FIXME: We don't support anything interesting yet.
+// if (DysymtabLC->LocalSymbolsIndex != 0)
+// return Error("NOT YET IMPLEMENTED: local symbol entries");
+// if (DysymtabLC->ExternalSymbolsIndex != 0)
+// return Error("NOT YET IMPLEMENTED: non-external symbol entries");
+// if (DysymtabLC->UndefinedSymbolsIndex != SymtabLC->NumSymbolTableEntries)
+// return Error("NOT YET IMPLEMENTED: undefined symbol entries");
+ }
+
+ // Load the segment load command.
+ if (SegmentLCI->Command.Type == macho::LCT_Segment) {
+ if (loadSegment32(Obj.get(), SegmentLCI, SymtabLC))
+ return true;
+ } else {
+ if (loadSegment64(Obj.get(), SegmentLCI, SymtabLC))
+ return true;
+ }
+
+ return false;
+}
+
+// Assign an address to a symbol name and resolve all the relocations
+// associated with it.
+void RuntimeDyldMachO::reassignSymbolAddress(StringRef Name, uint8_t *Addr) {
+ // Assign the address in our symbol table.
+ SymbolTable[Name] = Addr;
+
+ RelocationList &Relocs = Relocations[Name];
+ for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
+ RelocationEntry &RE = Relocs[i];
+ uint8_t *Target = SymbolTable[RE.Target] + RE.Offset;
+ bool isPCRel = (RE.Data >> 24) & 1;
+ unsigned Type = (RE.Data >> 28) & 0xf;
+ unsigned Size = 1 << ((RE.Data >> 25) & 3);
+
+ DEBUG(dbgs() << "Resolving relocation at '" << RE.Target
+ << "' + " << RE.Offset << " (" << format("%p", Target) << ")"
+ << " from '" << Name << " (" << format("%p", Addr) << ")"
+ << "(" << (isPCRel ? "pcrel" : "absolute")
+ << ", type: " << Type << ", Size: " << Size << ").\n");
+
+ resolveRelocation(Target, Addr, isPCRel, Type, Size);
+ RE.isResolved = true;
+ }
+}
+
+bool RuntimeDyldMachO::isKnownFormat(const MemoryBuffer *InputBuffer) {
+ StringRef Magic = InputBuffer->getBuffer().slice(0, 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;
+}
+
+} // end namespace llvm
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