+//===- 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.
+//
//===----------------------------------------------------------------------===//
-// LLVM extract Utility
//
// 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/GlobalVariable.h"
-#include "llvm/Function.h"
-#include "llvm/Transforms/IPO/GlobalDCE.h"
-#include "llvm/Transforms/ConstantMerge.h"
-#include "llvm/Transforms/CleanupGCCOutput.h"
-#include "Support/CommandLine.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/System/Signals.h"
+#include <iostream>
#include <memory>
+#include <fstream>
+using namespace llvm;
// InputFilename - The filename to read from.
-static cl::opt<string>
-InputFilename(cl::Positional, cl::desc("<input bytecode file>"),
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input bitcode file>"),
cl::init("-"), cl::value_desc("filename"));
-
-
-// ExtractFunc - The function to extract from the module... defaults to main.
-static cl::opt<string>
-ExtractFunc("func", cl::desc("Specify function to extract"), cl::init("main"),
- cl::value_desc("function"));
-
-
-struct FunctionExtractorPass : public Pass {
- const char *getPassName() const { return "Function Extractor"; }
-
- bool run(Module &M) {
- // Mark all global variables to be internal
- for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
- I->setInternalLinkage(true);
-
- Function *Named = 0;
-
- // Loop over all of the functions in the module, dropping all references in
- // functions that are not the named function.
- for (Module::iterator I = M.begin(), E = M.end(); I != E;)
- // Check to see if this is the named function!
- if (!Named && I->getName() == ExtractFunc) {
- // Yes, it is. Keep track of it...
- Named = I;
- // Make sure it's globally accessable...
- Named->setInternalLinkage(false);
+static cl::opt<std::string>
+OutputFilename("o", cl::desc("Specify output filename"),
+ cl::value_desc("filename"), cl::init("-"));
- // Remove the named function from the module.
- M.getFunctionList().remove(I);
- } else {
- // Nope it's not the named function, delete the body of the function
- I->dropAllReferences();
- ++I;
- }
+static cl::opt<bool>
+Force("f", cl::desc("Overwrite output files"));
- // All of the functions that still have uses now must be used by global
- // variables or the named function. Loop through them and create a new,
- // external function for the used ones... making all uses point to the new
- // functions.
- std::vector<Function*> NewFunctions;
-
- for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
- if (!I->use_empty()) {
- Function *New = new Function(I->getFunctionType(), false, I->getName());
- I->replaceAllUsesWith(New);
- NewFunctions.push_back(New);
- }
-
- // Now the module only has unused functions with their references dropped.
- // Delete them all now!
- M.getFunctionList().clear();
+static cl::opt<bool>
+DeleteFn("delete", cl::desc("Delete specified function from Module"));
- // Re-insert the named function...
- if (Named)
- M.getFunctionList().push_back(Named);
- else
- std::cerr << "Warning: Function '" << ExtractFunc << "' not found!\n";
-
- // Insert all of the function stubs...
- M.getFunctionList().insert(M.end(), NewFunctions.begin(),
- NewFunctions.end());
- return true;
- }
-};
+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... 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) {
- cl::ParseCommandLineOptions(argc, argv, " llvm extractor\n");
-
- std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
+ llvm_shutdown_obj X; // Call llvm_shutdown() on exit.
+ cl::ParseCommandLineOptions(argc, argv, "llvm extractor\n");
+ sys::PrintStackTraceOnErrorSignal();
+
+ 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) {
- std::cerr << "bytecode didn't read correctly.\n";
+ cerr << argv[0] << ": bitcode didn't read correctly.\n";
+ return 1;
+ }
+
+ // Figure out which function we should extract
+ Function *F = M.get()->getFunction(ExtractFunc);
+ if (F == 0) {
+ cerr << argv[0] << ": program doesn't contain function named '"
+ << ExtractFunc << "'!\n";
return 1;
}
- // In addition to just parsing the input from GCC, we also want to spiff it up
- // a little bit. Do this now.
- //
+ // 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 FunctionExtractorPass());
- Passes.add(createGlobalDCEPass()); // Delete unreachable globals
- Passes.add(createConstantMergePass()); // Merge dup global constants
- Passes.add(createCleanupGCCOutputPass()); // Fix gccisms
- Passes.add(new WriteBytecodePass(&std::cout)); // Write bytecode to file...
+ Passes.add(new TargetData(M.get())); // Use correct TargetData
+ // Either isolate the function or delete it from the Module
+ Passes.add(createFunctionExtractionPass(F, 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;
}