From 6e56331ed99e5b96de940dfdc53e438eef521a2e Mon Sep 17 00:00:00 2001 From: Jim Grosbach Date: Mon, 21 Mar 2011 22:15:52 +0000 Subject: Library-ize the dyld components of llvm-rtdyld. Move the dynamic linking functionality of the llvm-rtdyld program into an ExecutionEngine support library. Update llvm-rtdyld to just load an object file into memory, use the library to process it, then run the _main() function, if one is found. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128031 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/ExecutionEngine/Makefile | 2 +- lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt | 3 + lib/ExecutionEngine/RuntimeDyld/Makefile | 13 + lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp | 329 ++++++++++++++++++++++++ 4 files changed, 346 insertions(+), 1 deletion(-) create mode 100644 lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt create mode 100644 lib/ExecutionEngine/RuntimeDyld/Makefile create mode 100644 lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp (limited to 'lib/ExecutionEngine') diff --git a/lib/ExecutionEngine/Makefile b/lib/ExecutionEngine/Makefile index 1858d77661..9a649a52cf 100644 --- a/lib/ExecutionEngine/Makefile +++ b/lib/ExecutionEngine/Makefile @@ -8,6 +8,6 @@ ##===----------------------------------------------------------------------===## LEVEL = ../.. LIBRARYNAME = LLVMExecutionEngine -PARALLEL_DIRS = Interpreter JIT MCJIT +PARALLEL_DIRS = Interpreter JIT MCJIT RuntimeDyld include $(LEVEL)/Makefile.common diff --git a/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt b/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt new file mode 100644 index 0000000000..9e53f8757e --- /dev/null +++ b/lib/ExecutionEngine/RuntimeDyld/CMakeLists.txt @@ -0,0 +1,3 @@ +add_llvm_library(LLVMRuntimeDyld + RuntimeDyld.cpp + ) diff --git a/lib/ExecutionEngine/RuntimeDyld/Makefile b/lib/ExecutionEngine/RuntimeDyld/Makefile new file mode 100644 index 0000000000..5d6f26d950 --- /dev/null +++ b/lib/ExecutionEngine/RuntimeDyld/Makefile @@ -0,0 +1,13 @@ +##===- lib/ExecutionEngine/MCJIT/Makefile ------------------*- Makefile -*-===## +# +# The LLVM Compiler Infrastructure +# +# This file is distributed under the University of Illinois Open Source +# License. See LICENSE.TXT for details. +# +##===----------------------------------------------------------------------===## + +LEVEL = ../../.. +LIBRARYNAME = LLVMRuntimeDyld + +include $(LEVEL)/Makefile.common diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp new file mode 100644 index 0000000000..4fb017d757 --- /dev/null +++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp @@ -0,0 +1,329 @@ +//===-- RuntimeDyld.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. +// +//===----------------------------------------------------------------------===// +// +// Implementation of the MC-JIT runtime dynamic linker. +// +//===----------------------------------------------------------------------===// + +#include "llvm/ADT/OwningPtr.h" +#include "llvm/ADT/StringMap.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Twine.h" +#include "llvm/ExecutionEngine/RuntimeDyld.h" +#include "llvm/Object/MachOObject.h" +#include "llvm/Support/Memory.h" +#include "llvm/Support/MemoryBuffer.h" +#include "llvm/Support/system_error.h" +using namespace llvm; +using namespace llvm::object; + +namespace llvm { +class RuntimeDyldImpl { + // Master symbol table. As modules are loaded and external symbols are + // resolved, their addresses are stored here. + StringMap SymbolTable; + + // FIXME: Should have multiple data blocks, one for each loaded chunk of + // compiled code. + sys::MemoryBlock Data; + + 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; + } + + bool loadSegment32(const MachOObject *Obj, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC); + bool loadSegment64(const MachOObject *Obj, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC); + +public: + bool loadObject(MemoryBuffer *InputBuffer); + + void *getSymbolAddress(StringRef Name) { + // Use lookup() rather than [] because we don't want to add an entry + // if there isn't one already, which the [] operator does. + return SymbolTable.lookup(Name); + } + + sys::MemoryBlock getMemoryBlock() { return Data; } + + // 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; } +}; + + + +bool RuntimeDyldImpl:: +loadSegment32(const MachOObject *Obj, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC) { + InMemoryStruct Segment32LC; + Obj->ReadSegmentLoadCommand(*SegmentLCI, Segment32LC); + if (!Segment32LC) + return Error("unable to load segment load command"); + + // Map the segment into memory. + std::string ErrorStr; + Data = sys::Memory::AllocateRWX(Segment32LC->VMSize, 0, &ErrorStr); + if (!Data.base()) + return Error("unable to allocate memory block: '" + ErrorStr + "'"); + memcpy(Data.base(), Obj->getData(Segment32LC->FileOffset, + Segment32LC->FileSize).data(), + Segment32LC->FileSize); + memset((char*)Data.base() + Segment32LC->FileSize, 0, + Segment32LC->VMSize - Segment32LC->FileSize); + + // Bind the section indices to address. + void **SectionBases = new void*[Segment32LC->NumSections]; + for (unsigned i = 0; i != Segment32LC->NumSections; ++i) { + InMemoryStruct Sect; + Obj->ReadSection(*SegmentLCI, i, Sect); + if (!Sect) + return Error("unable to load section: '" + Twine(i) + "'"); + + // FIXME: We don't support relocations yet. + if (Sect->NumRelocationTableEntries != 0) + return Error("not yet implemented: relocations!"); + + // FIXME: Improve check. + if (Sect->Flags != 0x80000400) + return Error("unsupported section type!"); + + SectionBases[i] = (char*) Data.base() + Sect->Address; + } + + // Bind all the symbols to address. + for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { + InMemoryStruct STE; + Obj->ReadSymbolTableEntry(SymtabLC->SymbolTableOffset, i, STE); + if (!STE) + return Error("unable to read symbol: '" + Twine(i) + "'"); + if (STE->SectionIndex == 0) + return Error("unexpected undefined symbol!"); + + unsigned Index = STE->SectionIndex - 1; + if (Index >= Segment32LC->NumSections) + return Error("invalid section index for symbol: '" + Twine() + "'"); + + // Get the symbol name. + StringRef Name = Obj->getStringAtIndex(STE->StringIndex); + + // Get the section base address. + void *SectionBase = SectionBases[Index]; + + // Get the symbol address. + void *Address = (char*) SectionBase + STE->Value; + + // FIXME: Check the symbol type and flags. + if (STE->Type != 0xF) + return Error("unexpected symbol type!"); + if (STE->Flags != 0x0) + return Error("unexpected symbol type!"); + + SymbolTable[Name] = Address; + } + + delete SectionBases; + return false; +} + + +bool RuntimeDyldImpl:: +loadSegment64(const MachOObject *Obj, + const MachOObject::LoadCommandInfo *SegmentLCI, + const InMemoryStruct &SymtabLC) { + InMemoryStruct Segment64LC; + Obj->ReadSegment64LoadCommand(*SegmentLCI, Segment64LC); + if (!Segment64LC) + return Error("unable to load segment load command"); + + // Map the segment into memory. + std::string ErrorStr; + Data = sys::Memory::AllocateRWX(Segment64LC->VMSize, 0, &ErrorStr); + if (!Data.base()) + return Error("unable to allocate memory block: '" + ErrorStr + "'"); + memcpy(Data.base(), Obj->getData(Segment64LC->FileOffset, + Segment64LC->FileSize).data(), + Segment64LC->FileSize); + memset((char*)Data.base() + Segment64LC->FileSize, 0, + Segment64LC->VMSize - Segment64LC->FileSize); + + // Bind the section indices to address. + void **SectionBases = new void*[Segment64LC->NumSections]; + for (unsigned i = 0; i != Segment64LC->NumSections; ++i) { + InMemoryStruct Sect; + Obj->ReadSection64(*SegmentLCI, i, Sect); + if (!Sect) + return Error("unable to load section: '" + Twine(i) + "'"); + + // FIXME: We don't support relocations yet. + if (Sect->NumRelocationTableEntries != 0) + return Error("not yet implemented: relocations!"); + + // FIXME: Improve check. + if (Sect->Flags != 0x80000400) + return Error("unsupported section type!"); + + SectionBases[i] = (char*) Data.base() + Sect->Address; + } + + // Bind all the symbols to address. + for (unsigned i = 0; i != SymtabLC->NumSymbolTableEntries; ++i) { + InMemoryStruct STE; + Obj->ReadSymbol64TableEntry(SymtabLC->SymbolTableOffset, i, STE); + if (!STE) + return Error("unable to read symbol: '" + Twine(i) + "'"); + if (STE->SectionIndex == 0) + return Error("unexpected undefined symbol!"); + + unsigned Index = STE->SectionIndex - 1; + if (Index >= Segment64LC->NumSections) + return Error("invalid section index for symbol: '" + Twine() + "'"); + + // Get the symbol name. + StringRef Name = Obj->getStringAtIndex(STE->StringIndex); + + // Get the section base address. + void *SectionBase = SectionBases[Index]; + + // Get the symbol address. + void *Address = (char*) SectionBase + STE->Value; + + // FIXME: Check the symbol type and flags. + if (STE->Type != 0xF) + return Error("unexpected symbol type!"); + if (STE->Flags != 0x0) + return Error("unexpected symbol type!"); + + SymbolTable[Name] = Address; + } + + delete SectionBases; + return false; +} + + + +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 Obj( + MachOObject::LoadFromBuffer(InputBuffer, &ErrorStr)); + if (!Obj) + return Error("unable to load object: '" + ErrorStr + "'"); + + // Validate that the load commands match what we expect. + const MachOObject::LoadCommandInfo *SegmentLCI = 0, *SymtabLCI = 0, + *DysymtabLCI = 0; + for (unsigned i = 0; i != Obj->getHeader().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 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 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; +} + + +//===----------------------------------------------------------------------===// +// RuntimeDyld class implementation +RuntimeDyld::RuntimeDyld() { + Dyld = new RuntimeDyldImpl; +} + +RuntimeDyld::~RuntimeDyld() { + delete Dyld; +} + +bool RuntimeDyld::loadObject(MemoryBuffer *InputBuffer) { + return Dyld->loadObject(InputBuffer); +} + +void *RuntimeDyld::getSymbolAddress(StringRef Name) { + return Dyld->getSymbolAddress(Name); +} + +sys::MemoryBlock RuntimeDyld::getMemoryBlock() { + return Dyld->getMemoryBlock(); +} + +} // end namespace llvm -- cgit v1.2.3