| //===- ExtractFunction.cpp - Extract a function from Program --------------===// |
| // |
| // 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 file implements a method that extracts a function from program, cleans |
| // it up, and returns it as a new module. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "BugDriver.h" |
| #include "llvm/Constant.h" |
| #include "llvm/Module.h" |
| #include "llvm/PassManager.h" |
| #include "llvm/Pass.h" |
| #include "llvm/Type.h" |
| #include "llvm/Analysis/Verifier.h" |
| #include "llvm/Transforms/IPO.h" |
| #include "llvm/Transforms/Scalar.h" |
| #include "llvm/Transforms/Utils/Cloning.h" |
| #include "llvm/Target/TargetData.h" |
| #include "Support/CommandLine.h" |
| |
| bool DisableSimplifyCFG = false; |
| |
| namespace { |
| cl::opt<bool> |
| NoADCE("disable-adce", |
| cl::desc("Do not use the -adce pass to reduce testcases")); |
| cl::opt<bool> |
| NoDCE ("disable-dce", |
| cl::desc("Do not use the -dce pass to reduce testcases")); |
| cl::opt<bool, true> |
| NoSCFG("disable-simplifycfg", cl::location(DisableSimplifyCFG), |
| cl::desc("Do not use the -simplifycfg pass to reduce testcases")); |
| cl::opt<bool> |
| NoFinalCleanup("disable-final-cleanup", |
| cl::desc("Disable the final cleanup phase of narrowing")); |
| } |
| |
| /// deleteInstructionFromProgram - This method clones the current Program and |
| /// deletes the specified instruction from the cloned module. It then runs a |
| /// series of cleanup passes (ADCE and SimplifyCFG) to eliminate any code which |
| /// depends on the value. The modified module is then returned. |
| /// |
| Module *BugDriver::deleteInstructionFromProgram(Instruction *I, |
| unsigned Simplification) const { |
| Module *Result = CloneModule(Program); |
| |
| BasicBlock *PBB = I->getParent(); |
| Function *PF = PBB->getParent(); |
| |
| Module::iterator RFI = Result->begin(); // Get iterator to corresponding fn |
| std::advance(RFI, std::distance(Program->begin(), Module::iterator(PF))); |
| |
| Function::iterator RBI = RFI->begin(); // Get iterator to corresponding BB |
| std::advance(RBI, std::distance(PF->begin(), Function::iterator(PBB))); |
| |
| BasicBlock::iterator RI = RBI->begin(); // Get iterator to corresponding inst |
| std::advance(RI, std::distance(PBB->begin(), BasicBlock::iterator(I))); |
| I = RI; // Got the corresponding instruction! |
| |
| // If this instruction produces a value, replace any users with null values |
| if (I->getType() != Type::VoidTy) |
| I->replaceAllUsesWith(Constant::getNullValue(I->getType())); |
| |
| // Remove the instruction from the program. |
| I->getParent()->getInstList().erase(I); |
| |
| // Spiff up the output a little bit. |
| PassManager Passes; |
| // Make sure that the appropriate target data is always used... |
| Passes.add(new TargetData("bugpoint", Result)); |
| |
| if (Simplification > 2 && !NoADCE) |
| Passes.add(createAggressiveDCEPass()); // Remove dead code... |
| //Passes.add(createInstructionCombiningPass()); |
| if (Simplification > 1 && !NoDCE) |
| Passes.add(createDeadCodeEliminationPass()); |
| if (Simplification && !DisableSimplifyCFG) |
| Passes.add(createCFGSimplificationPass()); // Delete dead control flow |
| |
| Passes.add(createVerifierPass()); |
| Passes.run(*Result); |
| return Result; |
| } |
| |
| /// performFinalCleanups - This method clones the current Program and performs |
| /// a series of cleanups intended to get rid of extra cruft on the module |
| /// before handing it to the user... |
| /// |
| void BugDriver::performFinalCleanups(Module *M, bool MayModifySemantics) const { |
| // Allow disabling these passes if they crash bugpoint. |
| // |
| // FIXME: This should eventually run these passes in a pass list to prevent |
| // them from being able to crash bugpoint at all! |
| // |
| if (NoFinalCleanup) return; |
| |
| // Make all functions external, so GlobalDCE doesn't delete them... |
| for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) |
| I->setLinkage(GlobalValue::ExternalLinkage); |
| |
| PassManager CleanupPasses; |
| // Make sure that the appropriate target data is always used... |
| CleanupPasses.add(new TargetData("bugpoint", M)); |
| CleanupPasses.add(createFunctionResolvingPass()); |
| CleanupPasses.add(createGlobalDCEPass()); |
| CleanupPasses.add(createDeadTypeEliminationPass()); |
| CleanupPasses.add(createDeadArgEliminationPass(MayModifySemantics)); |
| CleanupPasses.add(createVerifierPass()); |
| CleanupPasses.run(*M); |
| } |