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Diffstat (limited to 'tools/bugpoint/CodeGeneratorBug.cpp')
| -rw-r--r-- | tools/bugpoint/CodeGeneratorBug.cpp | 311 |
1 files changed, 0 insertions, 311 deletions
diff --git a/tools/bugpoint/CodeGeneratorBug.cpp b/tools/bugpoint/CodeGeneratorBug.cpp deleted file mode 100644 index 60c8bf4d3c..0000000000 --- a/tools/bugpoint/CodeGeneratorBug.cpp +++ /dev/null @@ -1,311 +0,0 @@ -//===- CodeGeneratorBug.cpp - Debug code generation bugs ------------------===// -// -// 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 program code generation debugging support. -// -//===----------------------------------------------------------------------===// - -#include "BugDriver.h" -#include "ListReducer.h" -#include "llvm/Constants.h" -#include "llvm/DerivedTypes.h" -#include "llvm/GlobalValue.h" -#include "llvm/iMemory.h" -#include "llvm/iTerminators.h" -#include "llvm/iOther.h" -#include "llvm/Module.h" -#include "llvm/Pass.h" -#include "llvm/Analysis/Verifier.h" -#include "llvm/Support/Mangler.h" -#include "llvm/Transforms/Utils/BasicBlockUtils.h" -#include "llvm/Transforms/Utils/Cloning.h" -#include "llvm/Transforms/Utils/Linker.h" -#include "Support/CommandLine.h" -#include "Support/Debug.h" -#include "Support/StringExtras.h" -#include "Support/FileUtilities.h" -using namespace llvm; - -namespace llvm { - extern cl::list<std::string> InputArgv; - - class ReduceMisCodegenFunctions : public ListReducer<Function*> { - BugDriver &BD; - public: - ReduceMisCodegenFunctions(BugDriver &bd) : BD(bd) {} - - virtual TestResult doTest(std::vector<Function*> &Prefix, - std::vector<Function*> &Suffix) { - if (!Prefix.empty() && TestFuncs(Prefix)) - return KeepPrefix; - if (!Suffix.empty() && TestFuncs(Suffix)) - return KeepSuffix; - return NoFailure; - } - - bool TestFuncs(const std::vector<Function*> &CodegenTest, - bool KeepFiles = false); - }; -} - -bool ReduceMisCodegenFunctions::TestFuncs(const std::vector<Function*> &Funcs, - bool KeepFiles) { - std::cout << "Testing functions: "; - PrintFunctionList(Funcs); - std::cout << "\t"; - - // Clone the module for the two halves of the program we want. - Module *SafeModule = CloneModule(BD.getProgram()); - - // The JIT must extract the 'main' function. - std::vector<Function*> RealFuncs(Funcs); - if (BD.isExecutingJIT()) { - if (Function *F = BD.Program->getMainFunction()) - RealFuncs.push_back(F); - } - Module *TestModule = SplitFunctionsOutOfModule(SafeModule, RealFuncs); - - // This is only applicable if we are debugging the JIT: - // Find all external functions in the Safe modules that are actually used - // (called or taken address of), and make them call the JIT wrapper instead - if (BD.isExecutingJIT()) { - // Must delete `main' from Safe module if it has it - Function *safeMain = SafeModule->getNamedFunction("main"); - assert(safeMain && "`main' function not found in safe module!"); - DeleteFunctionBody(safeMain); - - // Add an external function "getPointerToNamedFunction" that JIT provides - // Prototype: void *getPointerToNamedFunction(const char* Name) - std::vector<const Type*> Params; - Params.push_back(PointerType::get(Type::SByteTy)); // std::string& - FunctionType *resolverTy = FunctionType::get(PointerType::get(Type::VoidTy), - Params, false /* isVarArg */); - Function *resolverFunc = new Function(resolverTy, - GlobalValue::ExternalLinkage, - "getPointerToNamedFunction", - SafeModule); - - // Use the function we just added to get addresses of functions we need - // Iterate over the global declarations in the Safe module - for (Module::iterator F=SafeModule->begin(),E=SafeModule->end(); F!=E; ++F){ - if (F->isExternal() && !F->use_empty() && &*F != resolverFunc && - F->getIntrinsicID() == 0 /* ignore intrinsics */ && - // Don't forward functions which are external in the test module too. - !TestModule->getNamedFunction(F->getName())->isExternal()) { - // If it has a non-zero use list, - // 1. Add a string constant with its name to the global file - Constant *InitArray = ConstantArray::get(F->getName()); - GlobalVariable *funcName = - new GlobalVariable(InitArray->getType(), true /* isConstant */, - GlobalValue::InternalLinkage, InitArray, - F->getName() + "_name", SafeModule); - - // 2. Use `GetElementPtr *funcName, 0, 0' to convert the string to an - // sbyte* so it matches the signature of the resolver function. - std::vector<Constant*> GEPargs(2, Constant::getNullValue(Type::IntTy)); - - // 3. Replace all uses of `func' with calls to resolver by: - // (a) Iterating through the list of uses of this function - // (b) Insert a cast instruction in front of each use - // (c) Replace use of old call with new call - - // GetElementPtr *funcName, ulong 0, ulong 0 - Value *GEP = - ConstantExpr::getGetElementPtr(ConstantPointerRef::get(funcName), - GEPargs); - std::vector<Value*> ResolverArgs; - ResolverArgs.push_back(GEP); - - // Insert code at the beginning of the function - while (!F->use_empty()) - if (Instruction *Inst = dyn_cast<Instruction>(F->use_back())) { - // call resolver(GetElementPtr...) - CallInst *resolve = new CallInst(resolverFunc, ResolverArgs, - "resolver", Inst); - // cast the result from the resolver to correctly-typed function - CastInst *castResolver = - new CastInst(resolve, PointerType::get(F->getFunctionType()), - "resolverCast", Inst); - // actually use the resolved function - Inst->replaceUsesOfWith(F, castResolver); - } else { - // FIXME: need to take care of cases where a function is used by - // something other than an instruction; e.g., global variable - // initializers and constant expressions. - std::cerr << "UNSUPPORTED: Non-instruction is using an external " - << "function, " << F->getName() << "().\n"; - abort(); - } - } - } - } - - if (verifyModule(*SafeModule) || verifyModule(*TestModule)) { - std::cerr << "Bugpoint has a bug, an corrupted a module!!\n"; - abort(); - } - - // Remove all functions from the Test module EXCEPT for the ones specified in - // Funcs. We know which ones these are because they are non-external in - // ToOptimize, but external in ToNotOptimize. - // - for (Module::iterator I = TestModule->begin(), E = TestModule->end();I!=E;++I) - if (!I->isExternal()) { - Function *TNOF = SafeModule->getFunction(I->getName(), - I->getFunctionType()); - assert(TNOF && "Function doesn't exist in ToNotOptimize module??"); - if (!TNOF->isExternal()) - DeleteFunctionBody(I); - } - - // Clean up the modules, removing extra cruft that we don't need anymore... - TestModule = BD.performFinalCleanups(TestModule); - - std::string TestModuleBC = getUniqueFilename("bugpoint.test.bc"); - if (BD.writeProgramToFile(TestModuleBC, TestModule)) { - std::cerr << "Error writing bytecode to `" << TestModuleBC << "'\nExiting."; - exit(1); - } - delete TestModule; - - // Make the shared library - std::string SafeModuleBC = getUniqueFilename("bugpoint.safe.bc"); - - if (BD.writeProgramToFile(SafeModuleBC, SafeModule)) { - std::cerr << "Error writing bytecode to `" << SafeModuleBC << "'\nExiting."; - exit(1); - } - std::string SharedObject = BD.compileSharedObject(SafeModuleBC); - delete SafeModule; - - // Run the code generator on the `Test' code, loading the shared library. - // The function returns whether or not the new output differs from reference. - int Result = BD.diffProgram(TestModuleBC, SharedObject, false); - - if (Result) - std::cerr << ": still failing!\n"; - else - std::cerr << ": didn't fail.\n"; - - if (KeepFiles) { - std::cout << "You can reproduce the problem with the command line: \n"; - if (BD.isExecutingJIT()) { - std::cout << " lli -load " << SharedObject << " " << TestModuleBC; - } else { - std::cout << " llc " << TestModuleBC << " -o " << TestModuleBC << ".s\n"; - std::cout << " gcc " << SharedObject << " " << TestModuleBC - << ".s -o " << TestModuleBC << ".exe -Wl,-R.\n"; - std::cout << " " << TestModuleBC << ".exe"; - } - for (unsigned i=0, e = InputArgv.size(); i != e; ++i) - std::cout << " " << InputArgv[i]; - std::cout << "\n"; - std::cout << "The shared object was created with:\n llc -march=c " - << SafeModuleBC << " -o temporary.c\n" - << " gcc -xc temporary.c -O2 -o " << SharedObject -#if defined(sparc) || defined(__sparc__) || defined(__sparcv9) - << " -G" // Compile a shared library, `-G' for Sparc -#else - << " -shared" // `-shared' for Linux/X86, maybe others -#endif - << " -fno-strict-aliasing\n"; - } else { - removeFile(TestModuleBC); - removeFile(SafeModuleBC); - removeFile(SharedObject); - } - return Result; -} - -static void DisambiguateGlobalSymbols(Module *M) { - // Try not to cause collisions by minimizing chances of renaming an - // already-external symbol, so take in external globals and functions as-is. - // The code should work correctly without disambiguation (assuming the same - // mangler is used by the two code generators), but having symbols with the - // same name causes warnings to be emitted by the code generator. - Mangler Mang(*M); - DEBUG(std::cerr << "Disambiguating globals (external-only)\n"); - for (Module::giterator I = M->gbegin(), E = M->gend(); I != E; ++I) - I->setName(Mang.getValueName(I)); - DEBUG(std::cerr << "Disambiguating functions (external-only)\n"); - for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I) - I->setName(Mang.getValueName(I)); -} - - -bool BugDriver::debugCodeGenerator() { - if ((void*)cbe == (void*)Interpreter) { - std::string Result = executeProgramWithCBE("bugpoint.cbe.out"); - std::cout << "\n*** The C backend cannot match the reference diff, but it " - << "is used as the 'known good'\n code generator, so I can't" - << " debug it. Perhaps you have a front-end problem?\n As a" - << " sanity check, I left the result of executing the program " - << "with the C backend\n in this file for you: '" - << Result << "'.\n"; - return true; - } - - // See if we can pin down which functions are being miscompiled... - // First, build a list of all of the non-external functions in the program. - std::vector<Function*> MisCodegenFunctions; - for (Module::iterator I = Program->begin(), E = Program->end(); I != E; ++I) - if (!I->isExternal()) - MisCodegenFunctions.push_back(I); - - // If we are executing the JIT, we *must* keep the function `main' in the - // module that is passed in, and not the shared library. However, we still - // want to be able to debug the `main' function alone. Thus, we create a new - // function `main' which just calls the old one. - if (isExecutingJIT()) { - // Get the `main' function - Function *oldMain = Program->getNamedFunction("main"); - assert(oldMain && "`main' function not found in program!"); - // Rename it - oldMain->setName("llvm_old_main"); - // Create a NEW `main' function with same type - Function *newMain = new Function(oldMain->getFunctionType(), - GlobalValue::ExternalLinkage, - "main", Program); - // Call the old main function and return its result - BasicBlock *BB = new BasicBlock("entry", newMain); - std::vector<Value*> args; - for (Function::aiterator I = newMain->abegin(), E = newMain->aend(), - OI = oldMain->abegin(); I != E; ++I, ++OI) { - I->setName(OI->getName()); // Copy argument names from oldMain - args.push_back(I); - } - CallInst *call = new CallInst(oldMain, args); - BB->getInstList().push_back(call); - - // if the type of old function wasn't void, return value of call - if (oldMain->getReturnType() != Type::VoidTy) { - new ReturnInst(call, BB); - } else { - new ReturnInst(0, BB); - } - } - - DisambiguateGlobalSymbols(Program); - - // Do the reduction... - if (!ReduceMisCodegenFunctions(*this).reduceList(MisCodegenFunctions)) { - std::cerr << "*** Execution matches reference output! " - << "bugpoint can't help you with your problem!\n"; - return false; - } - - std::cout << "\n*** The following functions are being miscompiled: "; - PrintFunctionList(MisCodegenFunctions); - std::cout << "\n"; - - // Output a bunch of bytecode files for the user... - ReduceMisCodegenFunctions(*this).TestFuncs(MisCodegenFunctions, true); - - return false; -} |