add a new BF->LLVM translator, contributed by Sterling Stein.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41881 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/examples/BrainF/BrainFDriver.cpp b/examples/BrainF/BrainFDriver.cpp
new file mode 100644
index 0000000..7d29fe6
--- /dev/null
+++ b/examples/BrainF/BrainFDriver.cpp
@@ -0,0 +1,156 @@
+//===-- BrainFDriver.cpp - BrainF compiler driver -----------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by Sterling Stein and is distributed under the
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===--------------------------------------------------------------------===//
+//
+// This program converts the BrainF language into LLVM assembly,
+// which it can then run using the JIT or output as BitCode.
+//
+// This implementation has a tape of 65536 bytes,
+// with the head starting in the middle.
+// Range checking is off by default, so be careful.
+// It can be enabled with -abc.
+//
+// Use:
+// ./BrainF -jit prog.bf #Run program now
+// ./BrainF -jit -abc prog.bf #Run program now safely
+// ./BrainF prog.bf #Write as BitCode
+//
+// lli prog.bf.bc #Run generated BitCode
+// llvm-ld -native -o=prog prog.bf.bc #Compile BitCode into native executable
+//
+//===--------------------------------------------------------------------===//
+
+#include "BrainF.h"
+#include "llvm/Constants.h"
+#include "llvm/ModuleProvider.h"
+#include "llvm/Analysis/Verifier.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/ExecutionEngine/GenericValue.h"
+#include "llvm/ExecutionEngine/JIT.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ManagedStatic.h"
+#include <fstream>
+#include <iostream>
+
+using namespace llvm;
+
+//Command line options
+
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input brainf>"));
+
+static cl::opt<std::string>
+OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"));
+
+static cl::opt<bool>
+ArrayBoundsChecking("abc", cl::desc("Enable array bounds checking"));
+
+static cl::opt<bool>
+JIT("jit", cl::desc("Run program Just-In-Time"));
+
+
+//Add main function so can be fully compiled
+void addMainFunction(Module *mod) {
+ //define i32 @main(i32 %argc, i8 **%argv)
+ Function *main_func = cast<Function>(mod->
+ getOrInsertFunction("main", IntegerType::Int32Ty, IntegerType::Int32Ty,
+ PointerType::get(PointerType::get(
+ IntegerType::Int8Ty)), NULL));
+ {
+ Function::arg_iterator args = main_func->arg_begin();
+ Value *arg_0 = args++;
+ arg_0->setName("argc");
+ Value *arg_1 = args++;
+ arg_1->setName("argv");
+ }
+
+ //main.0:
+ BasicBlock *bb = new BasicBlock("main.0", main_func);
+
+ //call void @brainf()
+ {
+ CallInst *brainf_call = new CallInst(mod->getFunction("brainf"),
+ "", bb);
+ brainf_call->setTailCall(false);
+ }
+
+ //ret i32 0
+ new ReturnInst(ConstantInt::get(APInt(32, 0)), bb);
+}
+
+int main(int argc, char **argv) {
+ cl::ParseCommandLineOptions(argc, argv, " BrainF compiler\n");
+
+ if (InputFilename == "") {
+ cerr<<"Error: You must specify the filename of the program to "
+ "be compiled. Use --help to see the options.\n";
+ abort();
+ }
+
+ //Get the output stream
+ std::ostream *out = &std::cout;
+ if (!JIT) {
+ if (OutputFilename == "") {
+ std::string base = InputFilename;
+ if (InputFilename == "-") {base = "a";}
+
+ //Use default filename
+ const char *suffix = ".bc";
+ OutputFilename = base+suffix;
+ }
+ if (OutputFilename != "-") {
+ out = new std::
+ ofstream(OutputFilename.c_str(),
+ std::ios::out | std::ios::trunc | std::ios::binary);
+ }
+ }
+
+ //Get the input stream
+ std::istream *in = &std::cin;
+ if (InputFilename != "-") {
+ in = new std::ifstream(InputFilename.c_str());
+ }
+
+ //Gather the compile flags
+ BrainF::CompileFlags cf = BrainF::flag_off;
+ if (ArrayBoundsChecking) {
+ cf = BrainF::CompileFlags(cf | BrainF::flag_arraybounds);
+ }
+
+ //Read the BrainF program
+ BrainF bf;
+ Module *mod = bf.parse(in, 65536, cf); //64 KiB
+ if (in != &std::cin) {delete in;}
+ addMainFunction(mod);
+
+ //Verify generated code
+ if (verifyModule(*mod)) {
+ cerr<<"Error: module failed verification. This shouldn't happen.\n";
+ abort();
+ }
+
+ //Write it out
+ if (JIT) {
+ cout<<"------- Running JIT -------\n";
+ ExistingModuleProvider *mp = new ExistingModuleProvider(mod);
+ ExecutionEngine *ee = ExecutionEngine::create(mp, false);
+ std::vector<GenericValue> args;
+ Function *brainf_func = mod->getFunction("brainf");
+ GenericValue gv = ee->runFunction(brainf_func, args);
+ } else {
+ WriteBitcodeToFile(mod, *out);
+ }
+
+ //Clean up
+ if (out != &std::cout) {delete out;}
+ delete mod;
+
+ llvm_shutdown();
+
+ return 0;
+}