static int generateobj(boost::shared_ptr<llvm::tool_output_file> Out , llvm::Module * module) { llvm::PassManager PM; llvm::TargetOptions Options; std::string Err; llvm::Triple TheTriple(module->getTargetTriple()); if (TheTriple.getTriple().empty()) TheTriple.setTriple(llvm::sys::getDefaultTargetTriple()); const llvm::Target* TheTarget = llvm::TargetRegistry::lookupTarget(TheTriple.getTriple(), Err); std::string MCPU,FeaturesStr; llvm::TargetMachine * machineTarget = TheTarget->createTargetMachine(TheTriple.getTriple(), MCPU, FeaturesStr, Options); // Figure out where we are going to send the output... llvm::formatted_raw_ostream FOS(Out->os()); if (machineTarget->addPassesToEmitFile(PM, FOS, llvm::TargetMachine::CGFT_ObjectFile,true)) { std::cerr << " target does not support generation of this" << " file type!\n"; return 1; } PM.run(*module); return 0; }
static Triple getTriple(const object::MachOObjectFile &Obj) { Triple TheTriple("unknown-unknown-unknown"); TheTriple.setArch(Triple::ArchType(Obj.getArch())); TheTriple.setObjectFormat(Triple::MachO); return TheTriple; }
static MCAsmInfo *createCheerpMCAsmInfo(const MCRegisterInfo &T, StringRef TT) { Triple TheTriple(TT); return new CheerpMCAsmInfo(TheTriple); }
int main(int ac, char **av) { SourceMgr SrcMgr; //LLVMInitializeX86TargetInfo(); llvm::InitializeAllTargetInfos(); //LLVMInitializeX86AsmParser(); llvm::InitializeAllTargetMCs(); //LLVMInitializeX86TargetMC(); llvm::InitializeAllAsmParsers(); //LLVMInitializeX86AsmParser(); llvm::InitializeAllDisassemblers(); //LLVMInitializeX86Disassembler(); // arg0: // llvm::Target encapsulating the "x86_64-apple-darwin14.5.0" information // see /lib/Support/Triple.cpp for the details //spec = llvm::sys::getDefaultTargetTriple(); //std::string machSpec = "x86_64-apple-windows"; // will produce a COFF //std::string machSpec = "x86_64-apple-darwin14.5.0"; // will produce a Mach-O std::string machSpec = "arm-none-none-eabi"; // //std::string machSpec = "x86_64-apple-darwin"; //std::string machSpec = "x86_64-thumb-linux-gnu"; //std::string machSpec = "x86_64-unknown-linux-gnu"; printf("machine spec: %s\n", machSpec.c_str()); machSpec = Triple::normalize(machSpec); printf("machine spec (normalized): %s\n", machSpec.c_str()); Triple TheTriple(machSpec); // Get the target specific parser. std::string Error; const Target *TheTarget = TargetRegistry::lookupTarget(/*arch*/"", TheTriple, Error); if (!TheTarget) { errs() << Error; return -1; } machSpec = TheTriple.getTriple(); printf("machine spec (returned): %s\n", machSpec.c_str()); printf("Target.getName(): %s\n", TheTarget->getName()); printf("Target.getShortDescription(): %s\n", TheTarget->getShortDescription()); /* from the target we get almost everything */ std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(machSpec)); std::unique_ptr<MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, machSpec)); std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo()); /* describes target instruction set */ MCSubtargetInfo *STI = TheTarget->createMCSubtargetInfo(machSpec, "", ""); /* subtarget instr set */ MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*MRI, machSpec, /* specific CPU */ ""); // arg0: // llvm::SourceMgr (Support/SourceMgr.h) that holds assembler source // has vector of llvm::SrcBuffer encaps (Support/MemoryBuffer.h) and vector of include dirs //std::string asmSrc = ".org 0x100, 0xAA\nfoo:\nxor %eax, %ebx\npush %rbp\njmp foo\nrdtsc\n"; //std::string asmSrc = ".text\n" "ldr pc, data_foo\n" "\n" "data_foo:\n" " .int 0x8\n" "\n" "loop:\n" "b loop\n"; //std::string asmSrc = ".text\n" "mov r2, r1\n"; std::string asmSrc = ".text\n" "ldr pc, data_foo\n" "data_foo:\n" ".int 0x8\n" "loop:\n" "b loop\n"; std::unique_ptr<MemoryBuffer> memBuf = MemoryBuffer::getMemBuffer(asmSrc); SrcMgr.AddNewSourceBuffer(std::move(memBuf), SMLoc()); // arg1: the machine code context MCObjectFileInfo MOFI; MCContext Ctx(MAI.get(), MRI.get(), &MOFI, &SrcMgr); MOFI.InitMCObjectFileInfo(TheTriple, Reloc::Default, CodeModel::Default, Ctx); // this is the assembler interface // -methods per .s statements (emit bytes, handle directive, etc.) // -remembers current section // -implementations that write a .s, or .o in various formats // // 1. the output stream ... a formatted_raw_ostream wraps a raw_ostream to provide // tracking of line and column position for padding and shit // // but raw_ostream is abstract and is implemented by raw_fd_ostream, raw_string_ostream, etc. /* output stream: raw_svector_ostream is a raw_pwrite_stream is a raw_ostream since a SmallString is SmallVector (svector) we can use this and retrieve bytes later with its .data() method */ SmallString<1024> smallString; raw_svector_ostream rso(smallString); /* code emitter needs 1) instruction set info 2) register info */ MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx); MCStreamer *as = TheTarget->createMCObjectStreamer( TheTriple, /* Triple */ Ctx, /* the MCContext */ *MAB, /* the AsmBackend, (fixups, relaxation, objs and elfs) */ rso, /* output stream raw_pwrite_stream */ CE, /* code emitter */ *STI, /* subtarget info */ true, /* relax all fixups */ true, /* incremental linker compatible */ false /* DWARFMustBeAtTheEnd */ ); std::string abi = "none"; MCTargetOptions toptions; toptions.MCUseDwarfDirectory = false; toptions.ABIName = abi; printf("trying to assemble, let's go..\n"); AssembleInput(TheTarget, SrcMgr, Ctx, *as, *MAI, *STI, *MCII, toptions); printf("done with AssembleInput()\n"); /* dump to file for debugging */ FILE *fp; fp = fopen("out.bin", "wb"); fwrite(smallString.data(), 1, smallString.size(), fp); fclose(fp); //int n = smallString.size(); int codeOffset=0, codeSize = 0; char *data = smallString.data(); if(*(uint32_t *)data == 0xFEEDFACF) { unsigned int idx = 0; idx += 0x20; /* skip mach_header_64 to first command */ idx += 0x48; /* advance into segment_command_64 to first section */ idx += 0x28; /* advance into section_64 to size */ uint64_t scn_size = *(uint64_t *)(data + idx); idx += 0x8; /* advance into section_64 to offset */ uint64_t scn_offset = *(uint64_t *)(data + idx); codeOffset = scn_offset; codeSize = scn_size; } else if(0==memcmp(data, "\x7F" "ELF\x01\x01\x01\x00", 8)) { /* assume four sections: NULL, .strtab, .text, .symtab */ uint32_t e_shoff = *(uint32_t *)(data + 0x20); uint32_t sh_offset = *(uint32_t *)(data + e_shoff + 2*0x28 + 0x10); /* second shdr */ uint32_t sh_size = *(uint32_t *)(data + e_shoff + 2*0x28 + 0x14); /* second shdr */ codeOffset = sh_offset; codeSize = sh_size; } else { printf("ERROR: couldn't identify type of output file\n"); } dump_bytes((unsigned char *)data + codeOffset, codeSize, 0); return 0; }