-//===----------------------------------------------------------------------===//
-// LLVM extract Utility
+//===- extract.cpp - LLVM function extraction utility ---------------------===//
//
// This utility changes the input module to only contain a single function,
// which is primarily used for debugging transformations.
ExtractFunc("func", cl::desc("Specify function to extract"), cl::init("main"),
cl::value_desc("function"));
-
-struct FunctionExtractorPass : public Pass {
- 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);
-
- // 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;
- }
-
- // 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();
-
- // 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 RegisterPass<FunctionExtractorPass> X("extract", "Function Extractor");
-
-
int main(int argc, char **argv) {
cl::ParseCommandLineOptions(argc, argv, " llvm extractor\n");
std::auto_ptr<Module> M(ParseBytecodeFile(InputFilename));
if (M.get() == 0) {
- std::cerr << "bytecode didn't read correctly.\n";
+ 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;
}
// a little bit. Do this now.
//
PassManager Passes;
- Passes.add(new FunctionExtractorPass());
+ Passes.add(createFunctionExtractionPass(F)); // Extract the function
Passes.add(createGlobalDCEPass()); // Delete unreachable globals
- Passes.add(createConstantMergePass()); // Merge dup global constants
+ Passes.add(createFunctionResolvingPass()); // Delete prototypes
Passes.add(createDeadTypeEliminationPass()); // Remove dead types...
Passes.add(new WriteBytecodePass(&std::cout)); // Write bytecode to file...