1 files changed, 106 insertions, 0 deletions
diff --git a/tools/llvm-extract/llvm-extract.cpp b/tools/llvm-extract/llvm-extract.cpp
new file mode 100644
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+++ b/tools/llvm-extract/llvm-extract.cpp
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+//===- llvm-extract.cpp - LLVM function extraction utility ----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and 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/Bytecode/Reader.h"
+#include "llvm/Bytecode/WriteBytecodePass.h"
+#include "llvm/Transforms/IPO.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/System/Signals.h"
+#include <memory>
+#include <fstream>
+using namespace llvm;
+
+// InputFilename - The filename to read from.
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input bytecode 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 function from Module"));
+
+// ExtractFunc - The function to extract from the module... defaults to main.
+static cl::opt<std::string>
+ExtractFunc("func", cl::desc("Specify function to extract"), cl::init("main"),
+            cl::value_desc("function"));
+
+int main(int argc, char **argv) {
+  try {
+    cl::ParseCommandLineOptions(argc, argv, " llvm extractor\n");
+    sys::PrintStackTraceOnErrorSignal();
+
+    std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
+    if (M.get() == 0) {
+      std::cerr << argv[0] << ": bytecode didn't read correctly.\n";
+      return 1;
+    }
+
+    // Figure out which function we should extract
+    Function *F = M.get()->getNamedFunction(ExtractFunc);
+    if (F == 0) {
+      std::cerr << argv[0] << ": program doesn't contain function named '"
+                << ExtractFunc << "'!\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("extract", M.get())); // Use correct TargetData
+    // Either isolate the function or delete it from the Module
+    Passes.add(createFunctionExtractionPass(F, DeleteFn));
+    Passes.add(createGlobalDCEPass());             // Delete unreachable globals
+    Passes.add(createFunctionResolvingPass());     // Delete prototypes
+    Passes.add(createDeadTypeEliminationPass());   // Remove dead types...
+
+    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!
+        std::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(new WriteBytecodePass(Out));  // Write bytecode to file...
+    Passes.run(*M.get());
+
+    if (Out != &std::cout)
+      delete Out;
+    return 0;
+  } catch (const std::string& msg) {
+    std::cerr << argv[0] << ": " << msg << "\n";
+  } catch (...) {
+    std::cerr << argv[0] << ": Unexpected unknown exception occurred.\n";
+  }
+  return 1;
+}