1 //===-- BrainFDriver.cpp - BrainF compiler driver -----------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===--------------------------------------------------------------------===// 9 // 10 // This program converts the BrainF language into LLVM assembly, 11 // which it can then run using the JIT or output as BitCode. 12 // 13 // This implementation has a tape of 65536 bytes, 14 // with the head starting in the middle. 15 // Range checking is off by default, so be careful. 16 // It can be enabled with -abc. 17 // 18 // Use: 19 // ./BrainF -jit prog.bf #Run program now 20 // ./BrainF -jit -abc prog.bf #Run program now safely 21 // ./BrainF prog.bf #Write as BitCode 22 // 23 // lli prog.bf.bc #Run generated BitCode 24 // 25 //===--------------------------------------------------------------------===// 26 27 #include "BrainF.h" 28 #include "llvm/Bitcode/ReaderWriter.h" 29 #include "llvm/ExecutionEngine/ExecutionEngine.h" 30 #include "llvm/ExecutionEngine/GenericValue.h" 31 #include "llvm/IR/Constants.h" 32 #include "llvm/IR/Verifier.h" 33 #include "llvm/Support/CommandLine.h" 34 #include "llvm/Support/FileSystem.h" 35 #include "llvm/Support/ManagedStatic.h" 36 #include "llvm/Support/TargetSelect.h" 37 #include "llvm/Support/raw_ostream.h" 38 #include <fstream> 39 #include <iostream> 40 using namespace llvm; 41 42 //Command line options 43 44 static cl::opt<std::string> 45 InputFilename(cl::Positional, cl::desc("<input brainf>")); 46 47 static cl::opt<std::string> 48 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename")); 49 50 static cl::opt<bool> 51 ArrayBoundsChecking("abc", cl::desc("Enable array bounds checking")); 52 53 static cl::opt<bool> 54 JIT("jit", cl::desc("Run program Just-In-Time")); 55 56 57 //Add main function so can be fully compiled 58 void addMainFunction(Module *mod) { 59 //define i32 @main(i32 %argc, i8 **%argv) 60 Function *main_func = cast<Function>(mod-> 61 getOrInsertFunction("main", IntegerType::getInt32Ty(mod->getContext()), 62 IntegerType::getInt32Ty(mod->getContext()), 63 PointerType::getUnqual(PointerType::getUnqual( 64 IntegerType::getInt8Ty(mod->getContext()))), NULL)); 65 { 66 Function::arg_iterator args = main_func->arg_begin(); 67 Value *arg_0 = args++; 68 arg_0->setName("argc"); 69 Value *arg_1 = args++; 70 arg_1->setName("argv"); 71 } 72 73 //main.0: 74 BasicBlock *bb = BasicBlock::Create(mod->getContext(), "main.0", main_func); 75 76 //call void @brainf() 77 { 78 CallInst *brainf_call = CallInst::Create(mod->getFunction("brainf"), 79 "", bb); 80 brainf_call->setTailCall(false); 81 } 82 83 //ret i32 0 84 ReturnInst::Create(mod->getContext(), 85 ConstantInt::get(mod->getContext(), APInt(32, 0)), bb); 86 } 87 88 int main(int argc, char **argv) { 89 cl::ParseCommandLineOptions(argc, argv, " BrainF compiler\n"); 90 91 LLVMContext &Context = getGlobalContext(); 92 93 if (InputFilename == "") { 94 errs() << "Error: You must specify the filename of the program to " 95 "be compiled. Use --help to see the options.\n"; 96 abort(); 97 } 98 99 //Get the output stream 100 raw_ostream *out = &outs(); 101 if (!JIT) { 102 if (OutputFilename == "") { 103 std::string base = InputFilename; 104 if (InputFilename == "-") { base = "a"; } 105 106 // Use default filename. 107 OutputFilename = base+".bc"; 108 } 109 if (OutputFilename != "-") { 110 std::error_code EC; 111 out = new raw_fd_ostream(OutputFilename, EC, sys::fs::F_None); 112 } 113 } 114 115 //Get the input stream 116 std::istream *in = &std::cin; 117 if (InputFilename != "-") 118 in = new std::ifstream(InputFilename.c_str()); 119 120 //Gather the compile flags 121 BrainF::CompileFlags cf = BrainF::flag_off; 122 if (ArrayBoundsChecking) 123 cf = BrainF::CompileFlags(cf | BrainF::flag_arraybounds); 124 125 //Read the BrainF program 126 BrainF bf; 127 std::unique_ptr<Module> Mod(bf.parse(in, 65536, cf, Context)); // 64 KiB 128 if (in != &std::cin) 129 delete in; 130 addMainFunction(Mod.get()); 131 132 //Verify generated code 133 if (verifyModule(*Mod)) { 134 errs() << "Error: module failed verification. This shouldn't happen.\n"; 135 abort(); 136 } 137 138 //Write it out 139 if (JIT) { 140 InitializeNativeTarget(); 141 142 outs() << "------- Running JIT -------\n"; 143 Module &M = *Mod; 144 ExecutionEngine *ee = EngineBuilder(std::move(Mod)).create(); 145 std::vector<GenericValue> args; 146 Function *brainf_func = M.getFunction("brainf"); 147 GenericValue gv = ee->runFunction(brainf_func, args); 148 } else { 149 WriteBitcodeToFile(Mod.get(), *out); 150 } 151 152 //Clean up 153 if (out != &outs()) 154 delete out; 155 156 llvm_shutdown(); 157 158 return 0; 159 } 160