| //===- GCOVProfiling.cpp - Insert edge counters for gcov profiling --------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This pass implements GCOV-style profiling. When this pass is run it emits |
| // "gcno" files next to the existing source, and instruments the code that runs |
| // to records the edges between blocks that run and emit a complementary "gcda" |
| // file on exit. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "insert-gcov-profiling" |
| |
| #include "ProfilingUtils.h" |
| #include "llvm/Transforms/Instrumentation.h" |
| #include "llvm/DebugInfo.h" |
| #include "llvm/IRBuilder.h" |
| #include "llvm/Instructions.h" |
| #include "llvm/Module.h" |
| #include "llvm/Pass.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/ADT/StringExtras.h" |
| #include "llvm/ADT/StringMap.h" |
| #include "llvm/ADT/UniqueVector.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/DebugLoc.h" |
| #include "llvm/Support/InstIterator.h" |
| #include "llvm/Support/PathV2.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/Transforms/Utils/ModuleUtils.h" |
| #include <string> |
| #include <utility> |
| using namespace llvm; |
| |
| namespace { |
| class GCOVProfiler : public ModulePass { |
| public: |
| static char ID; |
| GCOVProfiler() |
| : ModulePass(ID), EmitNotes(true), EmitData(true), Use402Format(false), |
| UseExtraChecksum(false) { |
| initializeGCOVProfilerPass(*PassRegistry::getPassRegistry()); |
| } |
| GCOVProfiler(bool EmitNotes, bool EmitData, bool use402Format = false, |
| bool useExtraChecksum = false) |
| : ModulePass(ID), EmitNotes(EmitNotes), EmitData(EmitData), |
| Use402Format(use402Format), UseExtraChecksum(useExtraChecksum) { |
| assert((EmitNotes || EmitData) && "GCOVProfiler asked to do nothing?"); |
| initializeGCOVProfilerPass(*PassRegistry::getPassRegistry()); |
| } |
| virtual const char *getPassName() const { |
| return "GCOV Profiler"; |
| } |
| private: |
| bool runOnModule(Module &M); |
| |
| // Create the GCNO files for the Module based on DebugInfo. |
| void emitGCNO(); |
| |
| // Modify the program to track transitions along edges and call into the |
| // profiling runtime to emit .gcda files when run. |
| bool emitProfileArcs(); |
| |
| // Get pointers to the functions in the runtime library. |
| Constant *getStartFileFunc(); |
| Constant *getIncrementIndirectCounterFunc(); |
| Constant *getEmitFunctionFunc(); |
| Constant *getEmitArcsFunc(); |
| Constant *getEndFileFunc(); |
| |
| // Create or retrieve an i32 state value that is used to represent the |
| // pred block number for certain non-trivial edges. |
| GlobalVariable *getEdgeStateValue(); |
| |
| // Produce a table of pointers to counters, by predecessor and successor |
| // block number. |
| GlobalVariable *buildEdgeLookupTable(Function *F, |
| GlobalVariable *Counter, |
| const UniqueVector<BasicBlock *> &Preds, |
| const UniqueVector<BasicBlock *> &Succs); |
| |
| // Add the function to write out all our counters to the global destructor |
| // list. |
| void insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*, MDNode*> >); |
| void insertIndirectCounterIncrement(); |
| void insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >); |
| |
| std::string mangleName(DICompileUnit CU, const char *NewStem); |
| |
| bool EmitNotes; |
| bool EmitData; |
| bool Use402Format; |
| bool UseExtraChecksum; |
| |
| Module *M; |
| LLVMContext *Ctx; |
| }; |
| } |
| |
| char GCOVProfiler::ID = 0; |
| INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling", |
| "Insert instrumentation for GCOV profiling", false, false) |
| |
| ModulePass *llvm::createGCOVProfilerPass(bool EmitNotes, bool EmitData, |
| bool Use402Format, |
| bool UseExtraChecksum) { |
| return new GCOVProfiler(EmitNotes, EmitData, Use402Format, UseExtraChecksum); |
| } |
| |
| namespace { |
| class GCOVRecord { |
| protected: |
| static const char *LinesTag; |
| static const char *FunctionTag; |
| static const char *BlockTag; |
| static const char *EdgeTag; |
| |
| GCOVRecord() {} |
| |
| void writeBytes(const char *Bytes, int Size) { |
| os->write(Bytes, Size); |
| } |
| |
| void write(uint32_t i) { |
| writeBytes(reinterpret_cast<char*>(&i), 4); |
| } |
| |
| // Returns the length measured in 4-byte blocks that will be used to |
| // represent this string in a GCOV file |
| unsigned lengthOfGCOVString(StringRef s) { |
| // A GCOV string is a length, followed by a NUL, then between 0 and 3 NULs |
| // padding out to the next 4-byte word. The length is measured in 4-byte |
| // words including padding, not bytes of actual string. |
| return (s.size() / 4) + 1; |
| } |
| |
| void writeGCOVString(StringRef s) { |
| uint32_t Len = lengthOfGCOVString(s); |
| write(Len); |
| writeBytes(s.data(), s.size()); |
| |
| // Write 1 to 4 bytes of NUL padding. |
| assert((unsigned)(4 - (s.size() % 4)) > 0); |
| assert((unsigned)(4 - (s.size() % 4)) <= 4); |
| writeBytes("\0\0\0\0", 4 - (s.size() % 4)); |
| } |
| |
| raw_ostream *os; |
| }; |
| const char *GCOVRecord::LinesTag = "\0\0\x45\x01"; |
| const char *GCOVRecord::FunctionTag = "\0\0\0\1"; |
| const char *GCOVRecord::BlockTag = "\0\0\x41\x01"; |
| const char *GCOVRecord::EdgeTag = "\0\0\x43\x01"; |
| |
| class GCOVFunction; |
| class GCOVBlock; |
| |
| // Constructed only by requesting it from a GCOVBlock, this object stores a |
| // list of line numbers and a single filename, representing lines that belong |
| // to the block. |
| class GCOVLines : public GCOVRecord { |
| public: |
| void addLine(uint32_t Line) { |
| Lines.push_back(Line); |
| } |
| |
| uint32_t length() { |
| // Here 2 = 1 for string length + 1 for '0' id#. |
| return lengthOfGCOVString(Filename) + 2 + Lines.size(); |
| } |
| |
| void writeOut() { |
| write(0); |
| writeGCOVString(Filename); |
| for (int i = 0, e = Lines.size(); i != e; ++i) |
| write(Lines[i]); |
| } |
| |
| GCOVLines(StringRef F, raw_ostream *os) |
| : Filename(F) { |
| this->os = os; |
| } |
| |
| private: |
| StringRef Filename; |
| SmallVector<uint32_t, 32> Lines; |
| }; |
| |
| // Represent a basic block in GCOV. Each block has a unique number in the |
| // function, number of lines belonging to each block, and a set of edges to |
| // other blocks. |
| class GCOVBlock : public GCOVRecord { |
| public: |
| GCOVLines &getFile(StringRef Filename) { |
| GCOVLines *&Lines = LinesByFile[Filename]; |
| if (!Lines) { |
| Lines = new GCOVLines(Filename, os); |
| } |
| return *Lines; |
| } |
| |
| void addEdge(GCOVBlock &Successor) { |
| OutEdges.push_back(&Successor); |
| } |
| |
| void writeOut() { |
| uint32_t Len = 3; |
| for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(), |
| E = LinesByFile.end(); I != E; ++I) { |
| Len += I->second->length(); |
| } |
| |
| writeBytes(LinesTag, 4); |
| write(Len); |
| write(Number); |
| for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(), |
| E = LinesByFile.end(); I != E; ++I) |
| I->second->writeOut(); |
| write(0); |
| write(0); |
| } |
| |
| ~GCOVBlock() { |
| DeleteContainerSeconds(LinesByFile); |
| } |
| |
| private: |
| friend class GCOVFunction; |
| |
| GCOVBlock(uint32_t Number, raw_ostream *os) |
| : Number(Number) { |
| this->os = os; |
| } |
| |
| uint32_t Number; |
| StringMap<GCOVLines *> LinesByFile; |
| SmallVector<GCOVBlock *, 4> OutEdges; |
| }; |
| |
| // A function has a unique identifier, a checksum (we leave as zero) and a |
| // set of blocks and a map of edges between blocks. This is the only GCOV |
| // object users can construct, the blocks and lines will be rooted here. |
| class GCOVFunction : public GCOVRecord { |
| public: |
| GCOVFunction(DISubprogram SP, raw_ostream *os, |
| bool Use402Format, bool UseExtraChecksum) { |
| this->os = os; |
| |
| Function *F = SP.getFunction(); |
| DEBUG(dbgs() << "Function: " << F->getName() << "\n"); |
| uint32_t i = 0; |
| for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { |
| Blocks[BB] = new GCOVBlock(i++, os); |
| } |
| ReturnBlock = new GCOVBlock(i++, os); |
| |
| writeBytes(FunctionTag, 4); |
| uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(SP.getName()) + |
| 1 + lengthOfGCOVString(SP.getFilename()) + 1; |
| if (UseExtraChecksum) |
| ++BlockLen; |
| write(BlockLen); |
| uint32_t Ident = reinterpret_cast<intptr_t>((MDNode*)SP); |
| write(Ident); |
| write(0); // lineno checksum |
| if (UseExtraChecksum) |
| write(0); // cfg checksum |
| writeGCOVString(SP.getName()); |
| writeGCOVString(SP.getFilename()); |
| write(SP.getLineNumber()); |
| } |
| |
| ~GCOVFunction() { |
| DeleteContainerSeconds(Blocks); |
| delete ReturnBlock; |
| } |
| |
| GCOVBlock &getBlock(BasicBlock *BB) { |
| return *Blocks[BB]; |
| } |
| |
| GCOVBlock &getReturnBlock() { |
| return *ReturnBlock; |
| } |
| |
| void writeOut() { |
| // Emit count of blocks. |
| writeBytes(BlockTag, 4); |
| write(Blocks.size() + 1); |
| for (int i = 0, e = Blocks.size() + 1; i != e; ++i) { |
| write(0); // No flags on our blocks. |
| } |
| DEBUG(dbgs() << Blocks.size() << " blocks.\n"); |
| |
| // Emit edges between blocks. |
| for (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(), |
| E = Blocks.end(); I != E; ++I) { |
| GCOVBlock &Block = *I->second; |
| if (Block.OutEdges.empty()) continue; |
| |
| writeBytes(EdgeTag, 4); |
| write(Block.OutEdges.size() * 2 + 1); |
| write(Block.Number); |
| for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) { |
| DEBUG(dbgs() << Block.Number << " -> " << Block.OutEdges[i]->Number |
| << "\n"); |
| write(Block.OutEdges[i]->Number); |
| write(0); // no flags |
| } |
| } |
| |
| // Emit lines for each block. |
| for (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(), |
| E = Blocks.end(); I != E; ++I) { |
| I->second->writeOut(); |
| } |
| } |
| |
| private: |
| DenseMap<BasicBlock *, GCOVBlock *> Blocks; |
| GCOVBlock *ReturnBlock; |
| }; |
| } |
| |
| std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) { |
| if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) { |
| for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) { |
| MDNode *N = GCov->getOperand(i); |
| if (N->getNumOperands() != 2) continue; |
| MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0)); |
| MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1)); |
| if (!GCovFile || !CompileUnit) continue; |
| if (CompileUnit == CU) { |
| SmallString<128> Filename = GCovFile->getString(); |
| sys::path::replace_extension(Filename, NewStem); |
| return Filename.str(); |
| } |
| } |
| } |
| |
| SmallString<128> Filename = CU.getFilename(); |
| sys::path::replace_extension(Filename, NewStem); |
| return sys::path::filename(Filename.str()); |
| } |
| |
| bool GCOVProfiler::runOnModule(Module &M) { |
| this->M = &M; |
| Ctx = &M.getContext(); |
| |
| if (EmitNotes) emitGCNO(); |
| if (EmitData) return emitProfileArcs(); |
| return false; |
| } |
| |
| void GCOVProfiler::emitGCNO() { |
| NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); |
| if (!CU_Nodes) return; |
| |
| for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { |
| // Each compile unit gets its own .gcno file. This means that whether we run |
| // this pass over the original .o's as they're produced, or run it after |
| // LTO, we'll generate the same .gcno files. |
| |
| DICompileUnit CU(CU_Nodes->getOperand(i)); |
| std::string ErrorInfo; |
| raw_fd_ostream out(mangleName(CU, "gcno").c_str(), ErrorInfo, |
| raw_fd_ostream::F_Binary); |
| if (!Use402Format) |
| out.write("oncg*404MVLL", 12); |
| else |
| out.write("oncg*204MVLL", 12); |
| |
| DIArray SPs = CU.getSubprograms(); |
| for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) { |
| DISubprogram SP(SPs.getElement(i)); |
| if (!SP.Verify()) continue; |
| |
| Function *F = SP.getFunction(); |
| if (!F) continue; |
| GCOVFunction Func(SP, &out, Use402Format, UseExtraChecksum); |
| |
| for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { |
| GCOVBlock &Block = Func.getBlock(BB); |
| TerminatorInst *TI = BB->getTerminator(); |
| if (int successors = TI->getNumSuccessors()) { |
| for (int i = 0; i != successors; ++i) { |
| Block.addEdge(Func.getBlock(TI->getSuccessor(i))); |
| } |
| } else if (isa<ReturnInst>(TI)) { |
| Block.addEdge(Func.getReturnBlock()); |
| } |
| |
| uint32_t Line = 0; |
| for (BasicBlock::iterator I = BB->begin(), IE = BB->end(); |
| I != IE; ++I) { |
| const DebugLoc &Loc = I->getDebugLoc(); |
| if (Loc.isUnknown()) continue; |
| if (Line == Loc.getLine()) continue; |
| Line = Loc.getLine(); |
| if (SP != getDISubprogram(Loc.getScope(*Ctx))) continue; |
| |
| GCOVLines &Lines = Block.getFile(SP.getFilename()); |
| Lines.addLine(Loc.getLine()); |
| } |
| } |
| Func.writeOut(); |
| } |
| out.write("\0\0\0\0\0\0\0\0", 8); // EOF |
| out.close(); |
| } |
| } |
| |
| bool GCOVProfiler::emitProfileArcs() { |
| NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); |
| if (!CU_Nodes) return false; |
| |
| bool Result = false; |
| bool InsertIndCounterIncrCode = false; |
| for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { |
| DICompileUnit CU(CU_Nodes->getOperand(i)); |
| DIArray SPs = CU.getSubprograms(); |
| SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP; |
| for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) { |
| DISubprogram SP(SPs.getElement(i)); |
| if (!SP.Verify()) continue; |
| Function *F = SP.getFunction(); |
| if (!F) continue; |
| if (!Result) Result = true; |
| unsigned Edges = 0; |
| for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { |
| TerminatorInst *TI = BB->getTerminator(); |
| if (isa<ReturnInst>(TI)) |
| ++Edges; |
| else |
| Edges += TI->getNumSuccessors(); |
| } |
| |
| ArrayType *CounterTy = |
| ArrayType::get(Type::getInt64Ty(*Ctx), Edges); |
| GlobalVariable *Counters = |
| new GlobalVariable(*M, CounterTy, false, |
| GlobalValue::InternalLinkage, |
| Constant::getNullValue(CounterTy), |
| "__llvm_gcov_ctr"); |
| CountersBySP.push_back(std::make_pair(Counters, (MDNode*)SP)); |
| |
| UniqueVector<BasicBlock *> ComplexEdgePreds; |
| UniqueVector<BasicBlock *> ComplexEdgeSuccs; |
| |
| unsigned Edge = 0; |
| for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { |
| TerminatorInst *TI = BB->getTerminator(); |
| int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors(); |
| if (Successors) { |
| IRBuilder<> Builder(TI); |
| |
| if (Successors == 1) { |
| Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0, |
| Edge); |
| Value *Count = Builder.CreateLoad(Counter); |
| Count = Builder.CreateAdd(Count, |
| ConstantInt::get(Type::getInt64Ty(*Ctx),1)); |
| Builder.CreateStore(Count, Counter); |
| } else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) { |
| Value *Sel = Builder.CreateSelect( |
| BI->getCondition(), |
| ConstantInt::get(Type::getInt64Ty(*Ctx), Edge), |
| ConstantInt::get(Type::getInt64Ty(*Ctx), Edge + 1)); |
| SmallVector<Value *, 2> Idx; |
| Idx.push_back(Constant::getNullValue(Type::getInt64Ty(*Ctx))); |
| Idx.push_back(Sel); |
| Value *Counter = Builder.CreateInBoundsGEP(Counters, Idx); |
| Value *Count = Builder.CreateLoad(Counter); |
| Count = Builder.CreateAdd(Count, |
| ConstantInt::get(Type::getInt64Ty(*Ctx),1)); |
| Builder.CreateStore(Count, Counter); |
| } else { |
| ComplexEdgePreds.insert(BB); |
| for (int i = 0; i != Successors; ++i) |
| ComplexEdgeSuccs.insert(TI->getSuccessor(i)); |
| } |
| Edge += Successors; |
| } |
| } |
| |
| if (!ComplexEdgePreds.empty()) { |
| GlobalVariable *EdgeTable = |
| buildEdgeLookupTable(F, Counters, |
| ComplexEdgePreds, ComplexEdgeSuccs); |
| GlobalVariable *EdgeState = getEdgeStateValue(); |
| |
| Type *Int32Ty = Type::getInt32Ty(*Ctx); |
| for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) { |
| IRBuilder<> Builder(ComplexEdgePreds[i+1]->getTerminator()); |
| Builder.CreateStore(ConstantInt::get(Int32Ty, i), EdgeState); |
| } |
| for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) { |
| // call runtime to perform increment |
| BasicBlock::iterator InsertPt = |
| ComplexEdgeSuccs[i+1]->getFirstInsertionPt(); |
| IRBuilder<> Builder(InsertPt); |
| Value *CounterPtrArray = |
| Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0, |
| i * ComplexEdgePreds.size()); |
| |
| // Build code to increment the counter. |
| InsertIndCounterIncrCode = true; |
| Builder.CreateCall2(getIncrementIndirectCounterFunc(), |
| EdgeState, CounterPtrArray); |
| } |
| } |
| } |
| |
| insertCounterWriteout(CountersBySP); |
| insertFlush(CountersBySP); |
| } |
| |
| if (InsertIndCounterIncrCode) |
| insertIndirectCounterIncrement(); |
| |
| return Result; |
| } |
| |
| // All edges with successors that aren't branches are "complex", because it |
| // requires complex logic to pick which counter to update. |
| GlobalVariable *GCOVProfiler::buildEdgeLookupTable( |
| Function *F, |
| GlobalVariable *Counters, |
| const UniqueVector<BasicBlock *> &Preds, |
| const UniqueVector<BasicBlock *> &Succs) { |
| // TODO: support invoke, threads. We rely on the fact that nothing can modify |
| // the whole-Module pred edge# between the time we set it and the time we next |
| // read it. Threads and invoke make this untrue. |
| |
| // emit [(succs * preds) x i64*], logically [succ x [pred x i64*]]. |
| Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx); |
| ArrayType *EdgeTableTy = ArrayType::get( |
| Int64PtrTy, Succs.size() * Preds.size()); |
| |
| Constant **EdgeTable = new Constant*[Succs.size() * Preds.size()]; |
| Constant *NullValue = Constant::getNullValue(Int64PtrTy); |
| for (int i = 0, ie = Succs.size() * Preds.size(); i != ie; ++i) |
| EdgeTable[i] = NullValue; |
| |
| unsigned Edge = 0; |
| for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) { |
| TerminatorInst *TI = BB->getTerminator(); |
| int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors(); |
| if (Successors > 1 && !isa<BranchInst>(TI) && !isa<ReturnInst>(TI)) { |
| for (int i = 0; i != Successors; ++i) { |
| BasicBlock *Succ = TI->getSuccessor(i); |
| IRBuilder<> builder(Succ); |
| Value *Counter = builder.CreateConstInBoundsGEP2_64(Counters, 0, |
| Edge + i); |
| EdgeTable[((Succs.idFor(Succ)-1) * Preds.size()) + |
| (Preds.idFor(BB)-1)] = cast<Constant>(Counter); |
| } |
| } |
| Edge += Successors; |
| } |
| |
| ArrayRef<Constant*> V(&EdgeTable[0], Succs.size() * Preds.size()); |
| GlobalVariable *EdgeTableGV = |
| new GlobalVariable( |
| *M, EdgeTableTy, true, GlobalValue::InternalLinkage, |
| ConstantArray::get(EdgeTableTy, V), |
| "__llvm_gcda_edge_table"); |
| EdgeTableGV->setUnnamedAddr(true); |
| return EdgeTableGV; |
| } |
| |
| Constant *GCOVProfiler::getStartFileFunc() { |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), |
| Type::getInt8PtrTy(*Ctx), false); |
| return M->getOrInsertFunction("llvm_gcda_start_file", FTy); |
| } |
| |
| Constant *GCOVProfiler::getIncrementIndirectCounterFunc() { |
| Type *Int32Ty = Type::getInt32Ty(*Ctx); |
| Type *Int64Ty = Type::getInt64Ty(*Ctx); |
| Type *Args[] = { |
| Int32Ty->getPointerTo(), // uint32_t *predecessor |
| Int64Ty->getPointerTo()->getPointerTo() // uint64_t **counters |
| }; |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false); |
| return M->getOrInsertFunction("__llvm_gcov_indirect_counter_increment", FTy); |
| } |
| |
| Constant *GCOVProfiler::getEmitFunctionFunc() { |
| Type *Args[2] = { |
| Type::getInt32Ty(*Ctx), // uint32_t ident |
| Type::getInt8PtrTy(*Ctx), // const char *function_name |
| }; |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false); |
| return M->getOrInsertFunction("llvm_gcda_emit_function", FTy); |
| } |
| |
| Constant *GCOVProfiler::getEmitArcsFunc() { |
| Type *Args[] = { |
| Type::getInt32Ty(*Ctx), // uint32_t num_counters |
| Type::getInt64PtrTy(*Ctx), // uint64_t *counters |
| }; |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), |
| Args, false); |
| return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy); |
| } |
| |
| Constant *GCOVProfiler::getEndFileFunc() { |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false); |
| return M->getOrInsertFunction("llvm_gcda_end_file", FTy); |
| } |
| |
| GlobalVariable *GCOVProfiler::getEdgeStateValue() { |
| GlobalVariable *GV = M->getGlobalVariable("__llvm_gcov_global_state_pred"); |
| if (!GV) { |
| GV = new GlobalVariable(*M, Type::getInt32Ty(*Ctx), false, |
| GlobalValue::InternalLinkage, |
| ConstantInt::get(Type::getInt32Ty(*Ctx), |
| 0xffffffff), |
| "__llvm_gcov_global_state_pred"); |
| GV->setUnnamedAddr(true); |
| } |
| return GV; |
| } |
| |
| void GCOVProfiler::insertCounterWriteout( |
| ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) { |
| FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false); |
| Function *WriteoutF = M->getFunction("__llvm_gcov_writeout"); |
| if (!WriteoutF) |
| WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage, |
| "__llvm_gcov_writeout", M); |
| WriteoutF->setUnnamedAddr(true); |
| |
| BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF); |
| IRBuilder<> Builder(BB); |
| |
| Constant *StartFile = getStartFileFunc(); |
| Constant *EmitFunction = getEmitFunctionFunc(); |
| Constant *EmitArcs = getEmitArcsFunc(); |
| Constant *EndFile = getEndFileFunc(); |
| |
| NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu"); |
| if (CU_Nodes) { |
| for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) { |
| DICompileUnit CU(CU_Nodes->getOperand(i)); |
| std::string FilenameGcda = mangleName(CU, "gcda"); |
| Builder.CreateCall(StartFile, |
| Builder.CreateGlobalStringPtr(FilenameGcda)); |
| for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator |
| I = CountersBySP.begin(), E = CountersBySP.end(); |
| I != E; ++I) { |
| DISubprogram SP(I->second); |
| intptr_t ident = reinterpret_cast<intptr_t>(I->second); |
| Builder.CreateCall2(EmitFunction, |
| ConstantInt::get(Type::getInt32Ty(*Ctx), ident), |
| Builder.CreateGlobalStringPtr(SP.getName())); |
| |
| GlobalVariable *GV = I->first; |
| unsigned Arcs = |
| cast<ArrayType>(GV->getType()->getElementType())->getNumElements(); |
| Builder.CreateCall2(EmitArcs, |
| ConstantInt::get(Type::getInt32Ty(*Ctx), Arcs), |
| Builder.CreateConstGEP2_64(GV, 0, 0)); |
| } |
| Builder.CreateCall(EndFile); |
| } |
| } |
| Builder.CreateRetVoid(); |
| |
| // Create a small bit of code that registers the "__llvm_gcov_writeout" |
| // function to be executed at exit. |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false); |
| Function *F = Function::Create(FTy, GlobalValue::InternalLinkage, |
| "__llvm_gcov_init", M); |
| F->setUnnamedAddr(true); |
| F->setLinkage(GlobalValue::InternalLinkage); |
| Attributes::Builder B; |
| B.addAttribute(Attributes::NoInline); |
| F->addFnAttr(Attributes::get(B)); |
| |
| BB = BasicBlock::Create(*Ctx, "entry", F); |
| Builder.SetInsertPoint(BB); |
| |
| FTy = FunctionType::get(Type::getInt32Ty(*Ctx), |
| PointerType::get(FTy, 0), false); |
| Constant *AtExitFn = M->getOrInsertFunction("atexit", FTy); |
| Builder.CreateCall(AtExitFn, WriteoutF); |
| Builder.CreateRetVoid(); |
| |
| appendToGlobalCtors(*M, F, 0); |
| } |
| |
| void GCOVProfiler::insertIndirectCounterIncrement() { |
| Function *Fn = |
| cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc()); |
| Fn->setUnnamedAddr(true); |
| Fn->setLinkage(GlobalValue::InternalLinkage); |
| Attributes::Builder B; |
| B.addAttribute(Attributes::NoInline); |
| Fn->addFnAttr(Attributes::get(B)); |
| |
| Type *Int32Ty = Type::getInt32Ty(*Ctx); |
| Type *Int64Ty = Type::getInt64Ty(*Ctx); |
| Constant *NegOne = ConstantInt::get(Int32Ty, 0xffffffff); |
| |
| // Create basic blocks for function. |
| BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", Fn); |
| IRBuilder<> Builder(BB); |
| |
| BasicBlock *PredNotNegOne = BasicBlock::Create(*Ctx, "", Fn); |
| BasicBlock *CounterEnd = BasicBlock::Create(*Ctx, "", Fn); |
| BasicBlock *Exit = BasicBlock::Create(*Ctx, "exit", Fn); |
| |
| // uint32_t pred = *predecessor; |
| // if (pred == 0xffffffff) return; |
| Argument *Arg = Fn->arg_begin(); |
| Arg->setName("predecessor"); |
| Value *Pred = Builder.CreateLoad(Arg, "pred"); |
| Value *Cond = Builder.CreateICmpEQ(Pred, NegOne); |
| BranchInst::Create(Exit, PredNotNegOne, Cond, BB); |
| |
| Builder.SetInsertPoint(PredNotNegOne); |
| |
| // uint64_t *counter = counters[pred]; |
| // if (!counter) return; |
| Value *ZExtPred = Builder.CreateZExt(Pred, Int64Ty); |
| Arg = llvm::next(Fn->arg_begin()); |
| Arg->setName("counters"); |
| Value *GEP = Builder.CreateGEP(Arg, ZExtPred); |
| Value *Counter = Builder.CreateLoad(GEP, "counter"); |
| Cond = Builder.CreateICmpEQ(Counter, |
| Constant::getNullValue(Int64Ty->getPointerTo())); |
| Builder.CreateCondBr(Cond, Exit, CounterEnd); |
| |
| // ++*counter; |
| Builder.SetInsertPoint(CounterEnd); |
| Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter), |
| ConstantInt::get(Int64Ty, 1)); |
| Builder.CreateStore(Add, Counter); |
| Builder.CreateBr(Exit); |
| |
| // Fill in the exit block. |
| Builder.SetInsertPoint(Exit); |
| Builder.CreateRetVoid(); |
| } |
| |
| void GCOVProfiler:: |
| insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) { |
| FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false); |
| Function *FlushF = M->getFunction("__gcov_flush"); |
| if (!FlushF) |
| FlushF = Function::Create(FTy, GlobalValue::InternalLinkage, |
| "__gcov_flush", M); |
| else |
| FlushF->setLinkage(GlobalValue::InternalLinkage); |
| FlushF->setUnnamedAddr(true); |
| |
| BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF); |
| |
| // Write out the current counters. |
| Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout"); |
| assert(WriteoutF && "Need to create the writeout function first!"); |
| |
| IRBuilder<> Builder(Entry); |
| Builder.CreateCall(WriteoutF); |
| |
| // Zero out the counters. |
| for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator |
| I = CountersBySP.begin(), E = CountersBySP.end(); |
| I != E; ++I) { |
| GlobalVariable *GV = I->first; |
| Constant *Null = Constant::getNullValue(GV->getType()->getElementType()); |
| Builder.CreateStore(Null, GV); |
| } |
| |
| Type *RetTy = FlushF->getReturnType(); |
| if (RetTy == Type::getVoidTy(*Ctx)) |
| Builder.CreateRetVoid(); |
| else if (RetTy->isIntegerTy()) |
| // Used if __gcov_flush was implicitly declared. |
| Builder.CreateRet(ConstantInt::get(RetTy, 0)); |
| else |
| report_fatal_error("invalid return type for __gcov_flush"); |
| } |