1 files changed, 136 insertions, 0 deletions
diff --git a/tools/llvm-extract/llvm-extract.cpp b/tools/llvm-extract/llvm-extract.cpp
new file mode 100644
index 000000000000..46840f2e223a
--- /dev/null
+++ b/tools/llvm-extract/llvm-extract.cpp
@@ -0,0 +1,136 @@
+//===- llvm-extract.cpp - LLVM function extraction utility ----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This utility changes the input module to only contain a single function,
+// which is primarily used for debugging transformations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Module.h"
+#include "llvm/PassManager.h"
+#include "llvm/Bitcode/ReaderWriter.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/PrettyStackTrace.h"
+#include "llvm/System/Signals.h"
+#include <iostream>
+#include <memory>
+#include <fstream>
+using namespace llvm;
+
+// InputFilename - The filename to read from.
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
+              cl::init("-"), cl::value_desc("filename"));
+
+static cl::opt<std::string>
+OutputFilename("o", cl::desc("Specify output filename"),
+               cl::value_desc("filename"), cl::init("-"));
+
+static cl::opt<bool>
+Force("f", cl::desc("Overwrite output files"));
+
+static cl::opt<bool>
+DeleteFn("delete", cl::desc("Delete specified Globals from Module"));
+
+static cl::opt<bool>
+Relink("relink",
+       cl::desc("Turn external linkage for callees of function to delete"));
+
+// ExtractFunc - The function to extract from the module... 
+static cl::opt<std::string>
+ExtractFunc("func", cl::desc("Specify function to extract"), cl::init(""),
+            cl::value_desc("function"));
+
+// ExtractGlobal - The global to extract from the module...
+static cl::opt<std::string>
+ExtractGlobal("glob", cl::desc("Specify global to extract"), cl::init(""),
+              cl::value_desc("global"));
+
+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 extractor\n");
+
+  std::auto_ptr<Module> M;
+  
+  MemoryBuffer *Buffer = MemoryBuffer::getFileOrSTDIN(InputFilename);
+  if (Buffer == 0) {
+    cerr << argv[0] << ": Error reading file '" + InputFilename + "'\n";
+    return 1;
+  } else {
+    M.reset(ParseBitcodeFile(Buffer));
+  }
+  delete Buffer;
+  
+  if (M.get() == 0) {
+    cerr << argv[0] << ": bitcode didn't read correctly.\n";
+    return 1;
+  }
+
+  // Figure out which function we should extract
+  GlobalVariable *G = !ExtractGlobal.empty() ?
+    M.get()->getNamedGlobal(ExtractGlobal) : 0;
+
+  // Figure out which function we should extract
+  if (ExtractFunc.empty() && ExtractGlobal.empty()) ExtractFunc = "main";
+  Function *F = M.get()->getFunction(ExtractFunc);
+
+  if (F == 0 && G == 0) {
+    cerr << argv[0] << ": program doesn't contain function named '"
+         << ExtractFunc << "' or a global named '" << ExtractGlobal << "'!\n";
+    return 1;
+  }
+
+  // In addition to deleting all other functions, we also want to spiff it
+  // up a little bit.  Do this now.
+  PassManager Passes;
+  Passes.add(new TargetData(M.get())); // Use correct TargetData
+  // Either isolate the function or delete it from the Module
+  std::vector<GlobalValue*> GVs;
+  if (F) GVs.push_back(F);
+  if (G) GVs.push_back(G);
+
+  Passes.add(createGVExtractionPass(GVs, DeleteFn, Relink));
+  if (!DeleteFn)
+    Passes.add(createGlobalDCEPass());           // Delete unreachable globals
+  Passes.add(createDeadTypeEliminationPass());   // Remove dead types...
+  Passes.add(createStripDeadPrototypesPass());   // Remove dead func decls
+
+  std::ostream *Out = 0;
+
+  if (OutputFilename != "-") {  // Not stdout?
+    if (!Force && std::ifstream(OutputFilename.c_str())) {
+      // If force is not specified, make sure not to overwrite a file!
+      cerr << argv[0] << ": error opening '" << OutputFilename
+           << "': file exists!\n"
+           << "Use -f command line argument to force output\n";
+      return 1;
+    }
+    std::ios::openmode io_mode = std::ios::out | std::ios::trunc |
+                                 std::ios::binary;
+    Out = new std::ofstream(OutputFilename.c_str(), io_mode);
+  } else {                      // Specified stdout
+    // FIXME: cout is not binary!
+    Out = &std::cout;
+  }
+
+  Passes.add(CreateBitcodeWriterPass(*Out));
+  Passes.run(*M.get());
+
+  if (Out != &std::cout)
+    delete Out;
+  return 0;
+}