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/ADT/APInt.h" 29 #include "llvm/Bitcode/ReaderWriter.h" 30 #include "llvm/ExecutionEngine/ExecutionEngine.h" 31 #include "llvm/ExecutionEngine/GenericValue.h" 32 #include "llvm/IR/BasicBlock.h" 33 #include "llvm/IR/Constants.h" 34 #include "llvm/IR/DerivedTypes.h" 35 #include "llvm/IR/Function.h" 36 #include "llvm/IR/Instructions.h" 37 #include "llvm/IR/LLVMContext.h" 38 #include "llvm/IR/Module.h" 39 #include "llvm/IR/Value.h" 40 #include "llvm/IR/Verifier.h" 41 #include "llvm/Support/Casting.h" 42 #include "llvm/Support/CommandLine.h" 43 #include "llvm/Support/FileSystem.h" 44 #include "llvm/Support/ManagedStatic.h" 45 #include "llvm/Support/TargetSelect.h" 46 #include "llvm/Support/raw_ostream.h" 47 #include <algorithm> 48 #include <cstdlib> 49 #include <fstream> 50 #include <iostream> 51 #include <memory> 52 #include <string> 53 #include <system_error> 54 #include <vector> 55 56 using namespace llvm; 57 58 //Command line options 59 60 static cl::opt<std::string> 61 InputFilename(cl::Positional, cl::desc("<input brainf>")); 62 63 static cl::opt<std::string> 64 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename")); 65 66 static cl::opt<bool> 67 ArrayBoundsChecking("abc", cl::desc("Enable array bounds checking")); 68 69 static cl::opt<bool> 70 JIT("jit", cl::desc("Run program Just-In-Time")); 71 72 //Add main function so can be fully compiled 73 void addMainFunction(Module *mod) { 74 //define i32 @main(i32 %argc, i8 **%argv) 75 Function *main_func = cast<Function>(mod-> 76 getOrInsertFunction("main", IntegerType::getInt32Ty(mod->getContext()), 77 IntegerType::getInt32Ty(mod->getContext()), 78 PointerType::getUnqual(PointerType::getUnqual( 79 IntegerType::getInt8Ty(mod->getContext()))), NULL)); 80 { 81 Function::arg_iterator args = main_func->arg_begin(); 82 Value *arg_0 = &*args++; 83 arg_0->setName("argc"); 84 Value *arg_1 = &*args++; 85 arg_1->setName("argv"); 86 } 87 88 //main.0: 89 BasicBlock *bb = BasicBlock::Create(mod->getContext(), "main.0", main_func); 90 91 //call void @brainf() 92 { 93 CallInst *brainf_call = CallInst::Create(mod->getFunction("brainf"), 94 "", bb); 95 brainf_call->setTailCall(false); 96 } 97 98 //ret i32 0 99 ReturnInst::Create(mod->getContext(), 100 ConstantInt::get(mod->getContext(), APInt(32, 0)), bb); 101 } 102 103 int main(int argc, char **argv) { 104 cl::ParseCommandLineOptions(argc, argv, " BrainF compiler\n"); 105 106 LLVMContext Context; 107 108 if (InputFilename == "") { 109 errs() << "Error: You must specify the filename of the program to " 110 "be compiled. Use --help to see the options.\n"; 111 abort(); 112 } 113 114 //Get the output stream 115 raw_ostream *out = &outs(); 116 if (!JIT) { 117 if (OutputFilename == "") { 118 std::string base = InputFilename; 119 if (InputFilename == "-") { base = "a"; } 120 121 // Use default filename. 122 OutputFilename = base+".bc"; 123 } 124 if (OutputFilename != "-") { 125 std::error_code EC; 126 out = new raw_fd_ostream(OutputFilename, EC, sys::fs::F_None); 127 } 128 } 129 130 //Get the input stream 131 std::istream *in = &std::cin; 132 if (InputFilename != "-") 133 in = new std::ifstream(InputFilename.c_str()); 134 135 //Gather the compile flags 136 BrainF::CompileFlags cf = BrainF::flag_off; 137 if (ArrayBoundsChecking) 138 cf = BrainF::CompileFlags(cf | BrainF::flag_arraybounds); 139 140 //Read the BrainF program 141 BrainF bf; 142 std::unique_ptr<Module> Mod(bf.parse(in, 65536, cf, Context)); // 64 KiB 143 if (in != &std::cin) 144 delete in; 145 addMainFunction(Mod.get()); 146 147 //Verify generated code 148 if (verifyModule(*Mod)) { 149 errs() << "Error: module failed verification. This shouldn't happen.\n"; 150 abort(); 151 } 152 153 //Write it out 154 if (JIT) { 155 InitializeNativeTarget(); 156 157 outs() << "------- Running JIT -------\n"; 158 Module &M = *Mod; 159 ExecutionEngine *ee = EngineBuilder(std::move(Mod)).create(); 160 std::vector<GenericValue> args; 161 Function *brainf_func = M.getFunction("brainf"); 162 GenericValue gv = ee->runFunction(brainf_func, args); 163 } else { 164 WriteBitcodeToFile(Mod.get(), *out); 165 } 166 167 //Clean up 168 if (out != &outs()) 169 delete out; 170 171 llvm_shutdown(); 172 173 return 0; 174 } 175
