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Add to RuntimeDyld support different object formats
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135037 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Danil Malyshev
@ -53,6 +53,7 @@ class RuntimeDyld {
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// RuntimeDyldImpl is the actual class. RuntimeDyld is just the public
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// RuntimeDyldImpl is the actual class. RuntimeDyld is just the public
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// interface.
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// interface.
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RuntimeDyldImpl *Dyld;
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RuntimeDyldImpl *Dyld;
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RTDyldMemoryManager *MM;
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public:
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public:
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RuntimeDyld(RTDyldMemoryManager*);
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RuntimeDyld(RTDyldMemoryManager*);
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~RuntimeDyld();
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~RuntimeDyld();
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@ -1,3 +1,4 @@
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add_llvm_library(LLVMRuntimeDyld
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add_llvm_library(LLVMRuntimeDyld
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RuntimeDyld.cpp
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RuntimeDyld.cpp
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RuntimeDyldMachO.cpp
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)
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)
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@ -1,4 +1,4 @@
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//===-- RuntimeDyld.h - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
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//===-- RuntimeDyld.cpp - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
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//
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//
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// The LLVM Compiler Infrastructure
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// The LLVM Compiler Infrastructure
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//
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//
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@ -12,118 +12,15 @@
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//===----------------------------------------------------------------------===//
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//===----------------------------------------------------------------------===//
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#define DEBUG_TYPE "dyld"
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#define DEBUG_TYPE "dyld"
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#include "llvm/ADT/OwningPtr.h"
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#include "RuntimeDyldImpl.h"
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/ADT/StringMap.h"
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#include "llvm/ADT/StringRef.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/Twine.h"
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#include "llvm/ExecutionEngine/RuntimeDyld.h"
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#include "llvm/Object/MachOObject.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/ErrorHandling.h"
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#include "llvm/Support/Format.h"
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#include "llvm/Support/Memory.h"
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#include "llvm/Support/MemoryBuffer.h"
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#include "llvm/Support/system_error.h"
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#include "llvm/Support/raw_ostream.h"
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using namespace llvm;
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using namespace llvm;
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using namespace llvm::object;
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using namespace llvm::object;
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// Empty out-of-line virtual destructor as the key function.
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// Empty out-of-line virtual destructor as the key function.
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RTDyldMemoryManager::~RTDyldMemoryManager() {}
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RTDyldMemoryManager::~RTDyldMemoryManager() {}
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RuntimeDyldImpl::~RuntimeDyldImpl() {}
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namespace llvm {
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namespace llvm {
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class RuntimeDyldImpl {
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unsigned CPUType;
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unsigned CPUSubtype;
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// The MemoryManager to load objects into.
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RTDyldMemoryManager *MemMgr;
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// FIXME: This all assumes we're dealing with external symbols for anything
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// explicitly referenced. I.e., we can index by name and things
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// will work out. In practice, this may not be the case, so we
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// should find a way to effectively generalize.
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// For each function, we have a MemoryBlock of it's instruction data.
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StringMap<sys::MemoryBlock> Functions;
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// Master symbol table. As modules are loaded and external symbols are
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// resolved, their addresses are stored here.
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StringMap<uint8_t*> SymbolTable;
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// For each symbol, keep a list of relocations based on it. Anytime
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// its address is reassigned (the JIT re-compiled the function, e.g.),
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// the relocations get re-resolved.
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struct RelocationEntry {
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std::string Target; // Object this relocation is contained in.
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uint64_t Offset; // Offset into the object for the relocation.
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uint32_t Data; // Second word of the raw macho relocation entry.
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int64_t Addend; // Addend encoded in the instruction itself, if any.
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bool isResolved; // Has this relocation been resolved previously?
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RelocationEntry(StringRef t, uint64_t offset, uint32_t data, int64_t addend)
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: Target(t), Offset(offset), Data(data), Addend(addend),
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isResolved(false) {}
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};
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typedef SmallVector<RelocationEntry, 4> RelocationList;
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StringMap<RelocationList> Relocations;
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// FIXME: Also keep a map of all the relocations contained in an object. Use
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// this to dynamically answer whether all of the relocations in it have
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// been resolved or not.
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bool HasError;
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std::string ErrorStr;
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// Set the error state and record an error string.
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bool Error(const Twine &Msg) {
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ErrorStr = Msg.str();
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HasError = true;
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return true;
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}
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void extractFunction(StringRef Name, uint8_t *StartAddress,
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uint8_t *EndAddress);
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bool resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
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unsigned Type, unsigned Size);
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bool resolveX86_64Relocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
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unsigned Type, unsigned Size);
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bool resolveARMRelocation(uintptr_t Address, uintptr_t Value, bool isPCRel,
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unsigned Type, unsigned Size);
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bool loadSegment32(const MachOObject *Obj,
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const MachOObject::LoadCommandInfo *SegmentLCI,
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const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
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bool loadSegment64(const MachOObject *Obj,
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const MachOObject::LoadCommandInfo *SegmentLCI,
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const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC);
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public:
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RuntimeDyldImpl(RTDyldMemoryManager *mm) : MemMgr(mm), HasError(false) {}
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bool loadObject(MemoryBuffer *InputBuffer);
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void *getSymbolAddress(StringRef Name) {
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// FIXME: Just look up as a function for now. Overly simple of course.
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// Work in progress.
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return SymbolTable.lookup(Name);
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}
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void resolveRelocations();
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void reassignSymbolAddress(StringRef Name, uint8_t *Addr);
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// Is the linker in an error state?
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bool hasError() { return HasError; }
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// Mark the error condition as handled and continue.
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void clearError() { HasError = false; }
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// Get the error message.
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StringRef getErrorString() { return ErrorStr; }
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};
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void RuntimeDyldImpl::extractFunction(StringRef Name, uint8_t *StartAddress,
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void RuntimeDyldImpl::extractFunction(StringRef Name, uint8_t *StartAddress,
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uint8_t *EndAddress) {
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uint8_t *EndAddress) {
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@ -144,472 +41,6 @@ void RuntimeDyldImpl::extractFunction(StringRef Name, uint8_t *StartAddress,
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DEBUG(dbgs() << " allocated to [" << Mem << ", " << Mem + Size << "]\n");
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DEBUG(dbgs() << " allocated to [" << Mem << ", " << Mem + Size << "]\n");
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}
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}
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bool RuntimeDyldImpl::
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resolveRelocation(uint8_t *Address, uint8_t *Value, bool isPCRel,
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unsigned Type, unsigned Size) {
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// This just dispatches to the proper target specific routine.
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switch (CPUType) {
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default: assert(0 && "Unsupported CPU type!");
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case mach::CTM_x86_64:
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return resolveX86_64Relocation((uintptr_t)Address, (uintptr_t)Value,
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isPCRel, Type, Size);
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case mach::CTM_ARM:
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return resolveARMRelocation((uintptr_t)Address, (uintptr_t)Value,
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isPCRel, Type, Size);
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}
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llvm_unreachable("");
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}
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bool RuntimeDyldImpl::
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resolveX86_64Relocation(uintptr_t Address, uintptr_t Value,
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bool isPCRel, unsigned Type,
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unsigned Size) {
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// If the relocation is PC-relative, the value to be encoded is the
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// pointer difference.
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if (isPCRel)
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// FIXME: It seems this value needs to be adjusted by 4 for an effective PC
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// address. Is that expected? Only for branches, perhaps?
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Value -= Address + 4;
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switch(Type) {
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default:
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llvm_unreachable("Invalid relocation type!");
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case macho::RIT_X86_64_Unsigned:
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case macho::RIT_X86_64_Branch: {
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// Mask in the target value a byte at a time (we don't have an alignment
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// guarantee for the target address, so this is safest).
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uint8_t *p = (uint8_t*)Address;
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for (unsigned i = 0; i < Size; ++i) {
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*p++ = (uint8_t)Value;
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Value >>= 8;
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}
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return false;
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}
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case macho::RIT_X86_64_Signed:
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case macho::RIT_X86_64_GOTLoad:
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case macho::RIT_X86_64_GOT:
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case macho::RIT_X86_64_Subtractor:
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case macho::RIT_X86_64_Signed1:
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case macho::RIT_X86_64_Signed2:
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case macho::RIT_X86_64_Signed4:
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case macho::RIT_X86_64_TLV:
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return Error("Relocation type not implemented yet!");
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}
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return false;
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}
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bool RuntimeDyldImpl::resolveARMRelocation(uintptr_t Address, uintptr_t Value,
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bool isPCRel, unsigned Type,
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unsigned Size) {
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// If the relocation is PC-relative, the value to be encoded is the
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// pointer difference.
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if (isPCRel) {
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Value -= Address;
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// ARM PCRel relocations have an effective-PC offset of two instructions
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// (four bytes in Thumb mode, 8 bytes in ARM mode).
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// FIXME: For now, assume ARM mode.
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Value -= 8;
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}
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switch(Type) {
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default:
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llvm_unreachable("Invalid relocation type!");
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case macho::RIT_Vanilla: {
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llvm_unreachable("Invalid relocation type!");
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// Mask in the target value a byte at a time (we don't have an alignment
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// guarantee for the target address, so this is safest).
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uint8_t *p = (uint8_t*)Address;
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for (unsigned i = 0; i < Size; ++i) {
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*p++ = (uint8_t)Value;
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Value >>= 8;
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}
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break;
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}
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case macho::RIT_ARM_Branch24Bit: {
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// Mask the value into the target address. We know instructions are
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// 32-bit aligned, so we can do it all at once.
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uint32_t *p = (uint32_t*)Address;
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// The low two bits of the value are not encoded.
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Value >>= 2;
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// Mask the value to 24 bits.
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Value &= 0xffffff;
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// FIXME: If the destination is a Thumb function (and the instruction
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// is a non-predicated BL instruction), we need to change it to a BLX
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// instruction instead.
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// Insert the value into the instruction.
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*p = (*p & ~0xffffff) | Value;
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break;
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}
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case macho::RIT_ARM_ThumbBranch22Bit:
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case macho::RIT_ARM_ThumbBranch32Bit:
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case macho::RIT_ARM_Half:
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case macho::RIT_ARM_HalfDifference:
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case macho::RIT_Pair:
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case macho::RIT_Difference:
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case macho::RIT_ARM_LocalDifference:
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case macho::RIT_ARM_PreboundLazyPointer:
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return Error("Relocation type not implemented yet!");
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}
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return false;
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}
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bool RuntimeDyldImpl::
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loadSegment32(const MachOObject *Obj,
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const MachOObject::LoadCommandInfo *SegmentLCI,
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const InMemoryStruct<macho::SymtabLoadCommand> &SymtabLC) {
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InMemoryStruct<macho::SegmentLoadCommand> SegmentLC;
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Obj->ReadSegmentLoadCommand(*SegmentLCI, SegmentLC);
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if (!SegmentLC)
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return Error("unable to load segment load command");
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for (unsigned SectNum = 0; SectNum != SegmentLC->NumSections; ++SectNum) {
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InMemoryStruct<macho::Section> Sect;
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Obj->ReadSection(*SegmentLCI, SectNum, Sect);
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if (!Sect)
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return Error("unable to load section: '" + Twine(SectNum) + "'");
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// FIXME: For the time being, we're only loading text segments.
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if (Sect->Flags != 0x80000400)
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continue;
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// Address and names of symbols in the section.
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typedef std::pair<uint64_t, StringRef> SymbolEntry;
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SmallVector<SymbolEntry, 64> Symbols;
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// Index of all the names, in this section or not. Used when we're
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// dealing with relocation entries.
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SmallVector<StringRef, 64> SymbolNames;
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for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) {
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InMemoryStruct<macho::SymbolTableEntry> STE;
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Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE);
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if (!STE)
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return Error("unable to read symbol: '" + Twine(i) + "'");
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if (STE->SectionIndex > SegmentLC->NumSections)
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return Error("invalid section index for symbol: '" + Twine(i) + "'");
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// Get the symbol name.
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StringRef Name = Obj->getStringAtIndex(STE->StringIndex);
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SymbolNames.push_back(Name);
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// Just skip symbols not defined in this section.
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if ((unsigned)STE->SectionIndex - 1 != SectNum)
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continue;
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// FIXME: Check the symbol type and flags.
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if (STE->Type != 0xF) // external, defined in this section.
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continue;
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// Flags == 0x8 marks a thumb function for ARM, which is fine as it
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// doesn't require any special handling here.
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if (STE->Flags != 0x0 && STE->Flags != 0x8)
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continue;
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// Remember the symbol.
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Symbols.push_back(SymbolEntry(STE->Value, Name));
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DEBUG(dbgs() << "Function sym: '" << Name << "' @ " <<
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(Sect->Address + STE->Value) << "\n");
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}
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// Sort the symbols by address, just in case they didn't come in that way.
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array_pod_sort(Symbols.begin(), Symbols.end());
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// If there weren't any functions (odd, but just in case...)
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if (!Symbols.size())
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continue;
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// Extract the function data.
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uint8_t *Base = (uint8_t*)Obj->getData(SegmentLC->FileOffset,
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SegmentLC->FileSize).data();
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for (unsigned i = 0, e = Symbols.size() - 1; i != e; ++i) {
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uint64_t StartOffset = Sect->Address + Symbols[i].first;
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uint64_t EndOffset = Symbols[i + 1].first - 1;
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DEBUG(dbgs() << "Extracting function: " << Symbols[i].second
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<< " from [" << StartOffset << ", " << EndOffset << "]\n");
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extractFunction(Symbols[i].second, Base + StartOffset, Base + EndOffset);
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}
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// The last symbol we do after since the end address is calculated
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// differently because there is no next symbol to reference.
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uint64_t StartOffset = Symbols[Symbols.size() - 1].first;
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uint64_t EndOffset = Sect->Size - 1;
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DEBUG(dbgs() << "Extracting function: " << Symbols[Symbols.size()-1].second
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<< " from [" << StartOffset << ", " << EndOffset << "]\n");
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extractFunction(Symbols[Symbols.size()-1].second,
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Base + StartOffset, Base + EndOffset);
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// Now extract the relocation information for each function and process it.
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for (unsigned j = 0; j != Sect->NumRelocationTableEntries; ++j) {
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InMemoryStruct<macho::RelocationEntry> RE;
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Obj->ReadRelocationEntry(Sect->RelocationTableOffset, j, RE);
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if (RE->Word0 & macho::RF_Scattered)
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return Error("NOT YET IMPLEMENTED: scattered relocations.");
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// Word0 of the relocation is the offset into the section where the
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// relocation should be applied. We need to translate that into an
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// 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.
|
// Resolve the relocations for all symbols we currently know about.
|
||||||
void RuntimeDyldImpl::resolveRelocations() {
|
void RuntimeDyldImpl::resolveRelocations() {
|
||||||
// Just iterate over the symbols in our symbol table and assign their
|
// Just iterate over the symbols in our symbol table and assign their
|
||||||
@ -620,35 +51,11 @@ void RuntimeDyldImpl::resolveRelocations() {
|
|||||||
reassignSymbolAddress(i->getKey(), i->getValue());
|
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 class implementation
|
||||||
RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *MM) {
|
RuntimeDyld::RuntimeDyld(RTDyldMemoryManager *mm) {
|
||||||
Dyld = new RuntimeDyldImpl(MM);
|
Dyld = 0;
|
||||||
|
MM = mm;
|
||||||
}
|
}
|
||||||
|
|
||||||
RuntimeDyld::~RuntimeDyld() {
|
RuntimeDyld::~RuntimeDyld() {
|
||||||
@ -656,6 +63,16 @@ RuntimeDyld::~RuntimeDyld() {
|
|||||||
}
|
}
|
||||||
|
|
||||||
bool RuntimeDyld::loadObject(MemoryBuffer *InputBuffer) {
|
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);
|
return Dyld->loadObject(InputBuffer);
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|||||||
152
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
Normal file
152
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
Normal file
@ -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
|
||||||
524
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
Normal file
524
lib/ExecutionEngine/RuntimeDyld/RuntimeDyldMachO.cpp
Normal file
@ -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
|
||||||
Reference in New Issue
Block a user