Add a skeleton driver for new machine code level fun. llvm-mc is meant

to be a test driver of other components in the system, which will develop
over time.

llvm-svn: 73732

llvm/tools/llvm-mc/llvm-mc.cpp

@@ -0,0 +1,61 @@
+//===-- llvm-dis.cpp - The low-level LLVM disassembler --------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This utility may be invoked in the following manner:
+//  llvm-dis [options]      - Read LLVM bitcode from stdin, write asm to stdout
+//  llvm-dis [options] x.bc - Read LLVM bitcode from the x.bc file, write asm
+//                            to the x.ll file.
+//  Options:
+//      --help   - Output information about command line switches
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/PrettyStackTrace.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/System/Signals.h"
+using namespace llvm;
+
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input file>"), cl::init("-"));
+
+static cl::opt<std::string>
+OutputFilename("o", cl::desc("Output filename"),
+               cl::value_desc("filename"));
+
+int main(int argc, char **argv) {
+  // Print a stack trace if we signal out.
+  sys::PrintStackTraceOnErrorSignal();
+  PrettyStackTraceProgram X(argc, argv);
+  
+  llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
+
+  cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
+
+  std::string ErrorMessage;
+  
+  MemoryBuffer *Buffer
+    = MemoryBuffer::getFileOrSTDIN(InputFilename, &ErrorMessage);
+
+  if (Buffer == 0) {
+    errs() << argv[0] << ": ";
+    if (ErrorMessage.size())
+      errs() << ErrorMessage << "\n";
+    else
+      errs() << "input file didn't read correctly.\n";
+    return 1;
+  }
+  
+  
+  
+  return 0;
+}
+