1 //===- GCOVProfiling.cpp - Insert edge counters for gcov profiling --------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This pass implements GCOV-style profiling. When this pass is run it emits
11 // "gcno" files next to the existing source, and instruments the code that runs
12 // to records the edges between blocks that run and emit a complementary "gcda"
15 //===----------------------------------------------------------------------===//
17 #include "llvm/Transforms/Instrumentation.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/ADT/Hashing.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/ADT/Statistic.h"
22 #include "llvm/ADT/StringExtras.h"
23 #include "llvm/ADT/StringMap.h"
24 #include "llvm/ADT/UniqueVector.h"
25 #include "llvm/IR/DebugInfo.h"
26 #include "llvm/IR/DebugLoc.h"
27 #include "llvm/IR/IRBuilder.h"
28 #include "llvm/IR/InstIterator.h"
29 #include "llvm/IR/Instructions.h"
30 #include "llvm/IR/IntrinsicInst.h"
31 #include "llvm/IR/Module.h"
32 #include "llvm/Pass.h"
33 #include "llvm/Support/CommandLine.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Support/FileSystem.h"
36 #include "llvm/Support/Path.h"
37 #include "llvm/Support/raw_ostream.h"
38 #include "llvm/Transforms/Utils/ModuleUtils.h"
45 #define DEBUG_TYPE "insert-gcov-profiling"
47 static cl::opt<std::string>
48 DefaultGCOVVersion("default-gcov-version", cl::init("402*"), cl::Hidden,
51 GCOVOptions GCOVOptions::getDefault() {
53 Options.EmitNotes = true;
54 Options.EmitData = true;
55 Options.UseCfgChecksum = false;
56 Options.NoRedZone = false;
57 Options.FunctionNamesInData = true;
59 if (DefaultGCOVVersion.size() != 4) {
60 llvm::report_fatal_error(std::string("Invalid -default-gcov-version: ") +
63 memcpy(Options.Version, DefaultGCOVVersion.c_str(), 4);
70 class GCOVProfiler : public ModulePass {
73 GCOVProfiler() : ModulePass(ID), Options(GCOVOptions::getDefault()) {
76 GCOVProfiler(const GCOVOptions &Options) : ModulePass(ID), Options(Options){
77 assert((Options.EmitNotes || Options.EmitData) &&
78 "GCOVProfiler asked to do nothing?");
81 const char *getPassName() const override {
82 return "GCOV Profiler";
87 ReversedVersion[0] = Options.Version[3];
88 ReversedVersion[1] = Options.Version[2];
89 ReversedVersion[2] = Options.Version[1];
90 ReversedVersion[3] = Options.Version[0];
91 ReversedVersion[4] = '\0';
92 initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
94 bool runOnModule(Module &M) override;
96 // Create the .gcno files for the Module based on DebugInfo.
97 void emitProfileNotes();
99 // Modify the program to track transitions along edges and call into the
100 // profiling runtime to emit .gcda files when run.
101 bool emitProfileArcs();
103 // Get pointers to the functions in the runtime library.
104 Constant *getStartFileFunc();
105 Constant *getIncrementIndirectCounterFunc();
106 Constant *getEmitFunctionFunc();
107 Constant *getEmitArcsFunc();
108 Constant *getSummaryInfoFunc();
109 Constant *getDeleteWriteoutFunctionListFunc();
110 Constant *getDeleteFlushFunctionListFunc();
111 Constant *getEndFileFunc();
113 // Create or retrieve an i32 state value that is used to represent the
114 // pred block number for certain non-trivial edges.
115 GlobalVariable *getEdgeStateValue();
117 // Produce a table of pointers to counters, by predecessor and successor
119 GlobalVariable *buildEdgeLookupTable(Function *F,
120 GlobalVariable *Counter,
121 const UniqueVector<BasicBlock *>&Preds,
122 const UniqueVector<BasicBlock*>&Succs);
124 // Add the function to write out all our counters to the global destructor
126 Function *insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*,
128 Function *insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
129 void insertIndirectCounterIncrement();
131 std::string mangleName(DICompileUnit CU, const char *NewStem);
135 // Reversed, NUL-terminated copy of Options.Version.
136 char ReversedVersion[5];
137 // Checksum, produced by hash of EdgeDestinations
138 SmallVector<uint32_t, 4> FileChecksums;
142 SmallVector<std::unique_ptr<GCOVFunction>, 16> Funcs;
146 char GCOVProfiler::ID = 0;
147 INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling",
148 "Insert instrumentation for GCOV profiling", false, false)
150 ModulePass *llvm::createGCOVProfilerPass(const GCOVOptions &Options) {
151 return new GCOVProfiler(Options);
154 static StringRef getFunctionName(DISubprogram SP) {
155 if (!SP.getLinkageName().empty())
156 return SP.getLinkageName();
163 static const char *const LinesTag;
164 static const char *const FunctionTag;
165 static const char *const BlockTag;
166 static const char *const EdgeTag;
170 void writeBytes(const char *Bytes, int Size) {
171 os->write(Bytes, Size);
174 void write(uint32_t i) {
175 writeBytes(reinterpret_cast<char*>(&i), 4);
178 // Returns the length measured in 4-byte blocks that will be used to
179 // represent this string in a GCOV file
180 static unsigned lengthOfGCOVString(StringRef s) {
181 // A GCOV string is a length, followed by a NUL, then between 0 and 3 NULs
182 // padding out to the next 4-byte word. The length is measured in 4-byte
183 // words including padding, not bytes of actual string.
184 return (s.size() / 4) + 1;
187 void writeGCOVString(StringRef s) {
188 uint32_t Len = lengthOfGCOVString(s);
190 writeBytes(s.data(), s.size());
192 // Write 1 to 4 bytes of NUL padding.
193 assert((unsigned)(4 - (s.size() % 4)) > 0);
194 assert((unsigned)(4 - (s.size() % 4)) <= 4);
195 writeBytes("\0\0\0\0", 4 - (s.size() % 4));
200 const char *const GCOVRecord::LinesTag = "\0\0\x45\x01";
201 const char *const GCOVRecord::FunctionTag = "\0\0\0\1";
202 const char *const GCOVRecord::BlockTag = "\0\0\x41\x01";
203 const char *const GCOVRecord::EdgeTag = "\0\0\x43\x01";
208 // Constructed only by requesting it from a GCOVBlock, this object stores a
209 // list of line numbers and a single filename, representing lines that belong
211 class GCOVLines : public GCOVRecord {
213 void addLine(uint32_t Line) {
214 assert(Line != 0 && "Line zero is not a valid real line number.");
215 Lines.push_back(Line);
218 uint32_t length() const {
219 // Here 2 = 1 for string length + 1 for '0' id#.
220 return lengthOfGCOVString(Filename) + 2 + Lines.size();
225 writeGCOVString(Filename);
226 for (int i = 0, e = Lines.size(); i != e; ++i)
230 GCOVLines(StringRef F, raw_ostream *os)
237 SmallVector<uint32_t, 32> Lines;
241 // Represent a basic block in GCOV. Each block has a unique number in the
242 // function, number of lines belonging to each block, and a set of edges to
244 class GCOVBlock : public GCOVRecord {
246 GCOVLines &getFile(StringRef Filename) {
247 GCOVLines *&Lines = LinesByFile[Filename];
249 Lines = new GCOVLines(Filename, os);
254 void addEdge(GCOVBlock &Successor) {
255 OutEdges.push_back(&Successor);
260 SmallVector<StringMapEntry<GCOVLines *> *, 32> SortedLinesByFile;
261 for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
262 E = LinesByFile.end(); I != E; ++I) {
263 Len += I->second->length();
264 SortedLinesByFile.push_back(&*I);
267 writeBytes(LinesTag, 4);
271 std::sort(SortedLinesByFile.begin(), SortedLinesByFile.end(),
272 [](StringMapEntry<GCOVLines *> *LHS,
273 StringMapEntry<GCOVLines *> *RHS) {
274 return LHS->getKey() < RHS->getKey();
276 for (SmallVectorImpl<StringMapEntry<GCOVLines *> *>::iterator
277 I = SortedLinesByFile.begin(), E = SortedLinesByFile.end();
279 (*I)->getValue()->writeOut();
285 DeleteContainerSeconds(LinesByFile);
289 friend class GCOVFunction;
291 GCOVBlock(uint32_t Number, raw_ostream *os)
297 StringMap<GCOVLines *> LinesByFile;
298 SmallVector<GCOVBlock *, 4> OutEdges;
301 // A function has a unique identifier, a checksum (we leave as zero) and a
302 // set of blocks and a map of edges between blocks. This is the only GCOV
303 // object users can construct, the blocks and lines will be rooted here.
304 class GCOVFunction : public GCOVRecord {
306 GCOVFunction(DISubprogram SP, raw_ostream *os, uint32_t Ident,
307 bool UseCfgChecksum) :
308 SP(SP), Ident(Ident), UseCfgChecksum(UseCfgChecksum), CfgChecksum(0) {
311 Function *F = SP.getFunction();
312 DEBUG(dbgs() << "Function: " << getFunctionName(SP) << "\n");
314 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
315 Blocks[BB] = new GCOVBlock(i++, os);
317 ReturnBlock = new GCOVBlock(i++, os);
319 std::string FunctionNameAndLine;
320 raw_string_ostream FNLOS(FunctionNameAndLine);
321 FNLOS << getFunctionName(SP) << SP.getLineNumber();
323 FuncChecksum = hash_value(FunctionNameAndLine);
327 DeleteContainerSeconds(Blocks);
331 GCOVBlock &getBlock(BasicBlock *BB) {
335 GCOVBlock &getReturnBlock() {
339 std::string getEdgeDestinations() {
340 std::string EdgeDestinations;
341 raw_string_ostream EDOS(EdgeDestinations);
342 Function *F = Blocks.begin()->first->getParent();
343 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
344 GCOVBlock &Block = *Blocks[I];
345 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i)
346 EDOS << Block.OutEdges[i]->Number;
348 return EdgeDestinations;
351 uint32_t getFuncChecksum() {
355 void setCfgChecksum(uint32_t Checksum) {
356 CfgChecksum = Checksum;
360 writeBytes(FunctionTag, 4);
361 uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(getFunctionName(SP)) +
362 1 + lengthOfGCOVString(SP.getFilename()) + 1;
370 writeGCOVString(getFunctionName(SP));
371 writeGCOVString(SP.getFilename());
372 write(SP.getLineNumber());
374 // Emit count of blocks.
375 writeBytes(BlockTag, 4);
376 write(Blocks.size() + 1);
377 for (int i = 0, e = Blocks.size() + 1; i != e; ++i) {
378 write(0); // No flags on our blocks.
380 DEBUG(dbgs() << Blocks.size() << " blocks.\n");
382 // Emit edges between blocks.
383 if (Blocks.empty()) return;
384 Function *F = Blocks.begin()->first->getParent();
385 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
386 GCOVBlock &Block = *Blocks[I];
387 if (Block.OutEdges.empty()) continue;
389 writeBytes(EdgeTag, 4);
390 write(Block.OutEdges.size() * 2 + 1);
392 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) {
393 DEBUG(dbgs() << Block.Number << " -> " << Block.OutEdges[i]->Number
395 write(Block.OutEdges[i]->Number);
396 write(0); // no flags
400 // Emit lines for each block.
401 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
402 Blocks[I]->writeOut();
409 uint32_t FuncChecksum;
411 uint32_t CfgChecksum;
412 DenseMap<BasicBlock *, GCOVBlock *> Blocks;
413 GCOVBlock *ReturnBlock;
417 std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) {
418 if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
419 for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
420 MDNode *N = GCov->getOperand(i);
421 if (N->getNumOperands() != 2) continue;
422 MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
423 MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
424 if (!GCovFile || !CompileUnit) continue;
425 if (CompileUnit == CU) {
426 SmallString<128> Filename = GCovFile->getString();
427 sys::path::replace_extension(Filename, NewStem);
428 return Filename.str();
433 SmallString<128> Filename = CU.getFilename();
434 sys::path::replace_extension(Filename, NewStem);
435 StringRef FName = sys::path::filename(Filename);
436 SmallString<128> CurPath;
437 if (sys::fs::current_path(CurPath)) return FName;
438 sys::path::append(CurPath, FName.str());
439 return CurPath.str();
442 bool GCOVProfiler::runOnModule(Module &M) {
444 Ctx = &M.getContext();
446 if (Options.EmitNotes) emitProfileNotes();
447 if (Options.EmitData) return emitProfileArcs();
451 static bool functionHasLines(Function *F) {
452 // Check whether this function actually has any source lines. Not only
453 // do these waste space, they also can crash gcov.
454 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
455 for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
457 // Debug intrinsic locations correspond to the location of the
458 // declaration, not necessarily any statements or expressions.
459 if (isa<DbgInfoIntrinsic>(I)) continue;
461 const DebugLoc &Loc = I->getDebugLoc();
462 if (Loc.isUnknown()) continue;
464 // Artificial lines such as calls to the global constructors.
465 if (Loc.getLine() == 0) continue;
473 void GCOVProfiler::emitProfileNotes() {
474 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
475 if (!CU_Nodes) return;
477 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
478 // Each compile unit gets its own .gcno file. This means that whether we run
479 // this pass over the original .o's as they're produced, or run it after
480 // LTO, we'll generate the same .gcno files.
482 DICompileUnit CU(CU_Nodes->getOperand(i));
483 std::string ErrorInfo;
484 raw_fd_ostream out(mangleName(CU, "gcno").c_str(), ErrorInfo,
486 std::string EdgeDestinations;
488 DIArray SPs = CU.getSubprograms();
489 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
490 DISubprogram SP(SPs.getElement(i));
491 assert((!SP || SP.isSubprogram()) &&
492 "A MDNode in subprograms of a CU should be null or a DISubprogram.");
496 Function *F = SP.getFunction();
498 if (!functionHasLines(F)) continue;
500 // gcov expects every function to start with an entry block that has a
501 // single successor, so split the entry block to make sure of that.
502 BasicBlock &EntryBlock = F->getEntryBlock();
503 BasicBlock::iterator It = EntryBlock.begin();
504 while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
506 EntryBlock.splitBasicBlock(It);
509 make_unique<GCOVFunction>(SP, &out, i, Options.UseCfgChecksum));
510 GCOVFunction &Func = *Funcs.back();
512 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
513 GCOVBlock &Block = Func.getBlock(BB);
514 TerminatorInst *TI = BB->getTerminator();
515 if (int successors = TI->getNumSuccessors()) {
516 for (int i = 0; i != successors; ++i) {
517 Block.addEdge(Func.getBlock(TI->getSuccessor(i)));
519 } else if (isa<ReturnInst>(TI)) {
520 Block.addEdge(Func.getReturnBlock());
524 for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
526 // Debug intrinsic locations correspond to the location of the
527 // declaration, not necessarily any statements or expressions.
528 if (isa<DbgInfoIntrinsic>(I)) continue;
530 const DebugLoc &Loc = I->getDebugLoc();
531 if (Loc.isUnknown()) continue;
533 // Artificial lines such as calls to the global constructors.
534 if (Loc.getLine() == 0) continue;
536 if (Line == Loc.getLine()) continue;
537 Line = Loc.getLine();
538 if (SP != getDISubprogram(Loc.getScope(*Ctx))) continue;
540 GCOVLines &Lines = Block.getFile(SP.getFilename());
541 Lines.addLine(Loc.getLine());
544 EdgeDestinations += Func.getEdgeDestinations();
547 FileChecksums.push_back(hash_value(EdgeDestinations));
548 out.write("oncg", 4);
549 out.write(ReversedVersion, 4);
550 out.write(reinterpret_cast<char*>(&FileChecksums.back()), 4);
552 for (auto &Func : Funcs) {
553 Func->setCfgChecksum(FileChecksums.back());
557 out.write("\0\0\0\0\0\0\0\0", 8); // EOF
562 bool GCOVProfiler::emitProfileArcs() {
563 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
564 if (!CU_Nodes) return false;
567 bool InsertIndCounterIncrCode = false;
568 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
569 DICompileUnit CU(CU_Nodes->getOperand(i));
570 DIArray SPs = CU.getSubprograms();
571 SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
572 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
573 DISubprogram SP(SPs.getElement(i));
574 assert((!SP || SP.isSubprogram()) &&
575 "A MDNode in subprograms of a CU should be null or a DISubprogram.");
578 Function *F = SP.getFunction();
580 if (!functionHasLines(F)) continue;
581 if (!Result) Result = true;
583 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
584 TerminatorInst *TI = BB->getTerminator();
585 if (isa<ReturnInst>(TI))
588 Edges += TI->getNumSuccessors();
591 ArrayType *CounterTy =
592 ArrayType::get(Type::getInt64Ty(*Ctx), Edges);
593 GlobalVariable *Counters =
594 new GlobalVariable(*M, CounterTy, false,
595 GlobalValue::InternalLinkage,
596 Constant::getNullValue(CounterTy),
598 CountersBySP.push_back(std::make_pair(Counters, (MDNode*)SP));
600 UniqueVector<BasicBlock *> ComplexEdgePreds;
601 UniqueVector<BasicBlock *> ComplexEdgeSuccs;
604 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
605 TerminatorInst *TI = BB->getTerminator();
606 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
608 if (Successors == 1) {
609 IRBuilder<> Builder(BB->getFirstInsertionPt());
610 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
612 Value *Count = Builder.CreateLoad(Counter);
613 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
614 Builder.CreateStore(Count, Counter);
615 } else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
616 IRBuilder<> Builder(BI);
617 Value *Sel = Builder.CreateSelect(BI->getCondition(),
618 Builder.getInt64(Edge),
619 Builder.getInt64(Edge + 1));
620 SmallVector<Value *, 2> Idx;
621 Idx.push_back(Builder.getInt64(0));
623 Value *Counter = Builder.CreateInBoundsGEP(Counters, Idx);
624 Value *Count = Builder.CreateLoad(Counter);
625 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
626 Builder.CreateStore(Count, Counter);
628 ComplexEdgePreds.insert(BB);
629 for (int i = 0; i != Successors; ++i)
630 ComplexEdgeSuccs.insert(TI->getSuccessor(i));
637 if (!ComplexEdgePreds.empty()) {
638 GlobalVariable *EdgeTable =
639 buildEdgeLookupTable(F, Counters,
640 ComplexEdgePreds, ComplexEdgeSuccs);
641 GlobalVariable *EdgeState = getEdgeStateValue();
643 for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
644 IRBuilder<> Builder(ComplexEdgePreds[i + 1]->getFirstInsertionPt());
645 Builder.CreateStore(Builder.getInt32(i), EdgeState);
648 for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
649 // Call runtime to perform increment.
650 IRBuilder<> Builder(ComplexEdgeSuccs[i+1]->getFirstInsertionPt());
651 Value *CounterPtrArray =
652 Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
653 i * ComplexEdgePreds.size());
655 // Build code to increment the counter.
656 InsertIndCounterIncrCode = true;
657 Builder.CreateCall2(getIncrementIndirectCounterFunc(),
658 EdgeState, CounterPtrArray);
663 Function *WriteoutF = insertCounterWriteout(CountersBySP);
664 Function *FlushF = insertFlush(CountersBySP);
666 // Create a small bit of code that registers the "__llvm_gcov_writeout" to
667 // be executed at exit and the "__llvm_gcov_flush" function to be executed
668 // when "__gcov_flush" is called.
669 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
670 Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
671 "__llvm_gcov_init", M);
672 F->setUnnamedAddr(true);
673 F->setLinkage(GlobalValue::InternalLinkage);
674 F->addFnAttr(Attribute::NoInline);
675 if (Options.NoRedZone)
676 F->addFnAttr(Attribute::NoRedZone);
678 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
679 IRBuilder<> Builder(BB);
681 FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
683 PointerType::get(FTy, 0),
684 PointerType::get(FTy, 0)
686 FTy = FunctionType::get(Builder.getVoidTy(), Params, false);
688 // Initialize the environment and register the local writeout and flush
690 Constant *GCOVInit = M->getOrInsertFunction("llvm_gcov_init", FTy);
691 Builder.CreateCall2(GCOVInit, WriteoutF, FlushF);
692 Builder.CreateRetVoid();
694 appendToGlobalCtors(*M, F, 0);
697 if (InsertIndCounterIncrCode)
698 insertIndirectCounterIncrement();
703 // All edges with successors that aren't branches are "complex", because it
704 // requires complex logic to pick which counter to update.
705 GlobalVariable *GCOVProfiler::buildEdgeLookupTable(
707 GlobalVariable *Counters,
708 const UniqueVector<BasicBlock *> &Preds,
709 const UniqueVector<BasicBlock *> &Succs) {
710 // TODO: support invoke, threads. We rely on the fact that nothing can modify
711 // the whole-Module pred edge# between the time we set it and the time we next
712 // read it. Threads and invoke make this untrue.
714 // emit [(succs * preds) x i64*], logically [succ x [pred x i64*]].
715 size_t TableSize = Succs.size() * Preds.size();
716 Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
717 ArrayType *EdgeTableTy = ArrayType::get(Int64PtrTy, TableSize);
719 std::unique_ptr<Constant * []> EdgeTable(new Constant *[TableSize]);
720 Constant *NullValue = Constant::getNullValue(Int64PtrTy);
721 for (size_t i = 0; i != TableSize; ++i)
722 EdgeTable[i] = NullValue;
725 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
726 TerminatorInst *TI = BB->getTerminator();
727 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
728 if (Successors > 1 && !isa<BranchInst>(TI) && !isa<ReturnInst>(TI)) {
729 for (int i = 0; i != Successors; ++i) {
730 BasicBlock *Succ = TI->getSuccessor(i);
731 IRBuilder<> Builder(Succ);
732 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
734 EdgeTable[((Succs.idFor(Succ)-1) * Preds.size()) +
735 (Preds.idFor(BB)-1)] = cast<Constant>(Counter);
741 ArrayRef<Constant*> V(&EdgeTable[0], TableSize);
742 GlobalVariable *EdgeTableGV =
744 *M, EdgeTableTy, true, GlobalValue::InternalLinkage,
745 ConstantArray::get(EdgeTableTy, V),
746 "__llvm_gcda_edge_table");
747 EdgeTableGV->setUnnamedAddr(true);
751 Constant *GCOVProfiler::getStartFileFunc() {
753 Type::getInt8PtrTy(*Ctx), // const char *orig_filename
754 Type::getInt8PtrTy(*Ctx), // const char version[4]
755 Type::getInt32Ty(*Ctx), // uint32_t checksum
757 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
758 return M->getOrInsertFunction("llvm_gcda_start_file", FTy);
761 Constant *GCOVProfiler::getIncrementIndirectCounterFunc() {
762 Type *Int32Ty = Type::getInt32Ty(*Ctx);
763 Type *Int64Ty = Type::getInt64Ty(*Ctx);
765 Int32Ty->getPointerTo(), // uint32_t *predecessor
766 Int64Ty->getPointerTo()->getPointerTo() // uint64_t **counters
768 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
769 return M->getOrInsertFunction("__llvm_gcov_indirect_counter_increment", FTy);
772 Constant *GCOVProfiler::getEmitFunctionFunc() {
774 Type::getInt32Ty(*Ctx), // uint32_t ident
775 Type::getInt8PtrTy(*Ctx), // const char *function_name
776 Type::getInt32Ty(*Ctx), // uint32_t func_checksum
777 Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
778 Type::getInt32Ty(*Ctx), // uint32_t cfg_checksum
780 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
781 return M->getOrInsertFunction("llvm_gcda_emit_function", FTy);
784 Constant *GCOVProfiler::getEmitArcsFunc() {
786 Type::getInt32Ty(*Ctx), // uint32_t num_counters
787 Type::getInt64PtrTy(*Ctx), // uint64_t *counters
789 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
790 return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy);
793 Constant *GCOVProfiler::getSummaryInfoFunc() {
794 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
795 return M->getOrInsertFunction("llvm_gcda_summary_info", FTy);
798 Constant *GCOVProfiler::getDeleteWriteoutFunctionListFunc() {
799 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
800 return M->getOrInsertFunction("llvm_delete_writeout_function_list", FTy);
803 Constant *GCOVProfiler::getDeleteFlushFunctionListFunc() {
804 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
805 return M->getOrInsertFunction("llvm_delete_flush_function_list", FTy);
808 Constant *GCOVProfiler::getEndFileFunc() {
809 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
810 return M->getOrInsertFunction("llvm_gcda_end_file", FTy);
813 GlobalVariable *GCOVProfiler::getEdgeStateValue() {
814 GlobalVariable *GV = M->getGlobalVariable("__llvm_gcov_global_state_pred");
816 GV = new GlobalVariable(*M, Type::getInt32Ty(*Ctx), false,
817 GlobalValue::InternalLinkage,
818 ConstantInt::get(Type::getInt32Ty(*Ctx),
820 "__llvm_gcov_global_state_pred");
821 GV->setUnnamedAddr(true);
826 Function *GCOVProfiler::insertCounterWriteout(
827 ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
828 FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
829 Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
831 WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
832 "__llvm_gcov_writeout", M);
833 WriteoutF->setUnnamedAddr(true);
834 WriteoutF->addFnAttr(Attribute::NoInline);
835 if (Options.NoRedZone)
836 WriteoutF->addFnAttr(Attribute::NoRedZone);
838 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
839 IRBuilder<> Builder(BB);
841 Constant *StartFile = getStartFileFunc();
842 Constant *EmitFunction = getEmitFunctionFunc();
843 Constant *EmitArcs = getEmitArcsFunc();
844 Constant *SummaryInfo = getSummaryInfoFunc();
845 Constant *EndFile = getEndFileFunc();
847 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
849 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
850 DICompileUnit CU(CU_Nodes->getOperand(i));
851 std::string FilenameGcda = mangleName(CU, "gcda");
852 uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
853 Builder.CreateCall3(StartFile,
854 Builder.CreateGlobalStringPtr(FilenameGcda),
855 Builder.CreateGlobalStringPtr(ReversedVersion),
856 Builder.getInt32(CfgChecksum));
857 for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
858 DISubprogram SP(CountersBySP[j].second);
859 uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
861 EmitFunction, Builder.getInt32(j),
862 Options.FunctionNamesInData ?
863 Builder.CreateGlobalStringPtr(getFunctionName(SP)) :
864 Constant::getNullValue(Builder.getInt8PtrTy()),
865 Builder.getInt32(FuncChecksum),
866 Builder.getInt8(Options.UseCfgChecksum),
867 Builder.getInt32(CfgChecksum));
869 GlobalVariable *GV = CountersBySP[j].first;
871 cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
872 Builder.CreateCall2(EmitArcs,
873 Builder.getInt32(Arcs),
874 Builder.CreateConstGEP2_64(GV, 0, 0));
876 Builder.CreateCall(SummaryInfo);
877 Builder.CreateCall(EndFile);
881 Builder.CreateRetVoid();
885 void GCOVProfiler::insertIndirectCounterIncrement() {
887 cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
888 Fn->setUnnamedAddr(true);
889 Fn->setLinkage(GlobalValue::InternalLinkage);
890 Fn->addFnAttr(Attribute::NoInline);
891 if (Options.NoRedZone)
892 Fn->addFnAttr(Attribute::NoRedZone);
894 // Create basic blocks for function.
895 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", Fn);
896 IRBuilder<> Builder(BB);
898 BasicBlock *PredNotNegOne = BasicBlock::Create(*Ctx, "", Fn);
899 BasicBlock *CounterEnd = BasicBlock::Create(*Ctx, "", Fn);
900 BasicBlock *Exit = BasicBlock::Create(*Ctx, "exit", Fn);
902 // uint32_t pred = *predecessor;
903 // if (pred == 0xffffffff) return;
904 Argument *Arg = Fn->arg_begin();
905 Arg->setName("predecessor");
906 Value *Pred = Builder.CreateLoad(Arg, "pred");
907 Value *Cond = Builder.CreateICmpEQ(Pred, Builder.getInt32(0xffffffff));
908 BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
910 Builder.SetInsertPoint(PredNotNegOne);
912 // uint64_t *counter = counters[pred];
913 // if (!counter) return;
914 Value *ZExtPred = Builder.CreateZExt(Pred, Builder.getInt64Ty());
915 Arg = std::next(Fn->arg_begin());
916 Arg->setName("counters");
917 Value *GEP = Builder.CreateGEP(Arg, ZExtPred);
918 Value *Counter = Builder.CreateLoad(GEP, "counter");
919 Cond = Builder.CreateICmpEQ(Counter,
920 Constant::getNullValue(
921 Builder.getInt64Ty()->getPointerTo()));
922 Builder.CreateCondBr(Cond, Exit, CounterEnd);
925 Builder.SetInsertPoint(CounterEnd);
926 Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
927 Builder.getInt64(1));
928 Builder.CreateStore(Add, Counter);
929 Builder.CreateBr(Exit);
931 // Fill in the exit block.
932 Builder.SetInsertPoint(Exit);
933 Builder.CreateRetVoid();
936 Function *GCOVProfiler::
937 insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
938 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
939 Function *FlushF = M->getFunction("__llvm_gcov_flush");
941 FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
942 "__llvm_gcov_flush", M);
944 FlushF->setLinkage(GlobalValue::InternalLinkage);
945 FlushF->setUnnamedAddr(true);
946 FlushF->addFnAttr(Attribute::NoInline);
947 if (Options.NoRedZone)
948 FlushF->addFnAttr(Attribute::NoRedZone);
950 BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
952 // Write out the current counters.
953 Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
954 assert(WriteoutF && "Need to create the writeout function first!");
956 IRBuilder<> Builder(Entry);
957 Builder.CreateCall(WriteoutF);
959 // Zero out the counters.
960 for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
961 I = CountersBySP.begin(), E = CountersBySP.end();
963 GlobalVariable *GV = I->first;
964 Constant *Null = Constant::getNullValue(GV->getType()->getElementType());
965 Builder.CreateStore(Null, GV);
968 Type *RetTy = FlushF->getReturnType();
969 if (RetTy == Type::getVoidTy(*Ctx))
970 Builder.CreateRetVoid();
971 else if (RetTy->isIntegerTy())
972 // Used if __llvm_gcov_flush was implicitly declared.
973 Builder.CreateRet(ConstantInt::get(RetTy, 0));
975 report_fatal_error("invalid return type for __llvm_gcov_flush");