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 string_ostream FnNameLine;
320 FnNameLine << getFunctionName(SP) << SP.getLineNumber();
321 FuncChecksum = hash_value(FnNameLine.str());
325 DeleteContainerSeconds(Blocks);
329 GCOVBlock &getBlock(BasicBlock *BB) {
333 GCOVBlock &getReturnBlock() {
337 std::string getEdgeDestinations() {
338 string_ostream EdgeDestinations;
339 Function *F = Blocks.begin()->first->getParent();
340 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
341 GCOVBlock &Block = *Blocks[I];
342 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i)
343 EdgeDestinations << Block.OutEdges[i]->Number;
345 return EdgeDestinations.str();
348 uint32_t getFuncChecksum() {
352 void setCfgChecksum(uint32_t Checksum) {
353 CfgChecksum = Checksum;
357 writeBytes(FunctionTag, 4);
358 uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(getFunctionName(SP)) +
359 1 + lengthOfGCOVString(SP.getFilename()) + 1;
367 writeGCOVString(getFunctionName(SP));
368 writeGCOVString(SP.getFilename());
369 write(SP.getLineNumber());
371 // Emit count of blocks.
372 writeBytes(BlockTag, 4);
373 write(Blocks.size() + 1);
374 for (int i = 0, e = Blocks.size() + 1; i != e; ++i) {
375 write(0); // No flags on our blocks.
377 DEBUG(dbgs() << Blocks.size() << " blocks.\n");
379 // Emit edges between blocks.
380 if (Blocks.empty()) return;
381 Function *F = Blocks.begin()->first->getParent();
382 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
383 GCOVBlock &Block = *Blocks[I];
384 if (Block.OutEdges.empty()) continue;
386 writeBytes(EdgeTag, 4);
387 write(Block.OutEdges.size() * 2 + 1);
389 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) {
390 DEBUG(dbgs() << Block.Number << " -> " << Block.OutEdges[i]->Number
392 write(Block.OutEdges[i]->Number);
393 write(0); // no flags
397 // Emit lines for each block.
398 for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
399 Blocks[I]->writeOut();
406 uint32_t FuncChecksum;
408 uint32_t CfgChecksum;
409 DenseMap<BasicBlock *, GCOVBlock *> Blocks;
410 GCOVBlock *ReturnBlock;
414 std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) {
415 if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
416 for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
417 MDNode *N = GCov->getOperand(i);
418 if (N->getNumOperands() != 2) continue;
419 MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
420 MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
421 if (!GCovFile || !CompileUnit) continue;
422 if (CompileUnit == CU) {
423 SmallString<128> Filename = GCovFile->getString();
424 sys::path::replace_extension(Filename, NewStem);
425 return Filename.str();
430 SmallString<128> Filename = CU.getFilename();
431 sys::path::replace_extension(Filename, NewStem);
432 StringRef FName = sys::path::filename(Filename);
433 SmallString<128> CurPath;
434 if (sys::fs::current_path(CurPath)) return FName;
435 sys::path::append(CurPath, FName.str());
436 return CurPath.str();
439 bool GCOVProfiler::runOnModule(Module &M) {
441 Ctx = &M.getContext();
443 if (Options.EmitNotes) emitProfileNotes();
444 if (Options.EmitData) return emitProfileArcs();
448 static bool functionHasLines(Function *F) {
449 // Check whether this function actually has any source lines. Not only
450 // do these waste space, they also can crash gcov.
451 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
452 for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
454 // Debug intrinsic locations correspond to the location of the
455 // declaration, not necessarily any statements or expressions.
456 if (isa<DbgInfoIntrinsic>(I)) continue;
458 const DebugLoc &Loc = I->getDebugLoc();
459 if (Loc.isUnknown()) continue;
461 // Artificial lines such as calls to the global constructors.
462 if (Loc.getLine() == 0) continue;
470 void GCOVProfiler::emitProfileNotes() {
471 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
472 if (!CU_Nodes) return;
474 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
475 // Each compile unit gets its own .gcno file. This means that whether we run
476 // this pass over the original .o's as they're produced, or run it after
477 // LTO, we'll generate the same .gcno files.
479 DICompileUnit CU(CU_Nodes->getOperand(i));
480 std::string ErrorInfo;
481 raw_fd_ostream out(mangleName(CU, "gcno").c_str(), ErrorInfo,
483 std::string EdgeDestinations;
485 DIArray SPs = CU.getSubprograms();
486 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
487 DISubprogram SP(SPs.getElement(i));
488 assert((!SP || SP.isSubprogram()) &&
489 "A MDNode in subprograms of a CU should be null or a DISubprogram.");
493 Function *F = SP.getFunction();
495 if (!functionHasLines(F)) continue;
497 // gcov expects every function to start with an entry block that has a
498 // single successor, so split the entry block to make sure of that.
499 BasicBlock &EntryBlock = F->getEntryBlock();
500 BasicBlock::iterator It = EntryBlock.begin();
501 while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
503 EntryBlock.splitBasicBlock(It);
506 make_unique<GCOVFunction>(SP, &out, i, Options.UseCfgChecksum));
507 GCOVFunction &Func = *Funcs.back();
509 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
510 GCOVBlock &Block = Func.getBlock(BB);
511 TerminatorInst *TI = BB->getTerminator();
512 if (int successors = TI->getNumSuccessors()) {
513 for (int i = 0; i != successors; ++i) {
514 Block.addEdge(Func.getBlock(TI->getSuccessor(i)));
516 } else if (isa<ReturnInst>(TI)) {
517 Block.addEdge(Func.getReturnBlock());
521 for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
523 // Debug intrinsic locations correspond to the location of the
524 // declaration, not necessarily any statements or expressions.
525 if (isa<DbgInfoIntrinsic>(I)) continue;
527 const DebugLoc &Loc = I->getDebugLoc();
528 if (Loc.isUnknown()) continue;
530 // Artificial lines such as calls to the global constructors.
531 if (Loc.getLine() == 0) continue;
533 if (Line == Loc.getLine()) continue;
534 Line = Loc.getLine();
535 if (SP != getDISubprogram(Loc.getScope(*Ctx))) continue;
537 GCOVLines &Lines = Block.getFile(SP.getFilename());
538 Lines.addLine(Loc.getLine());
541 EdgeDestinations += Func.getEdgeDestinations();
544 FileChecksums.push_back(hash_value(EdgeDestinations));
545 out.write("oncg", 4);
546 out.write(ReversedVersion, 4);
547 out.write(reinterpret_cast<char*>(&FileChecksums.back()), 4);
549 for (auto &Func : Funcs) {
550 Func->setCfgChecksum(FileChecksums.back());
554 out.write("\0\0\0\0\0\0\0\0", 8); // EOF
559 bool GCOVProfiler::emitProfileArcs() {
560 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
561 if (!CU_Nodes) return false;
564 bool InsertIndCounterIncrCode = false;
565 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
566 DICompileUnit CU(CU_Nodes->getOperand(i));
567 DIArray SPs = CU.getSubprograms();
568 SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
569 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
570 DISubprogram SP(SPs.getElement(i));
571 assert((!SP || SP.isSubprogram()) &&
572 "A MDNode in subprograms of a CU should be null or a DISubprogram.");
575 Function *F = SP.getFunction();
577 if (!functionHasLines(F)) continue;
578 if (!Result) Result = true;
580 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
581 TerminatorInst *TI = BB->getTerminator();
582 if (isa<ReturnInst>(TI))
585 Edges += TI->getNumSuccessors();
588 ArrayType *CounterTy =
589 ArrayType::get(Type::getInt64Ty(*Ctx), Edges);
590 GlobalVariable *Counters =
591 new GlobalVariable(*M, CounterTy, false,
592 GlobalValue::InternalLinkage,
593 Constant::getNullValue(CounterTy),
595 CountersBySP.push_back(std::make_pair(Counters, (MDNode*)SP));
597 UniqueVector<BasicBlock *> ComplexEdgePreds;
598 UniqueVector<BasicBlock *> ComplexEdgeSuccs;
601 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
602 TerminatorInst *TI = BB->getTerminator();
603 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
605 if (Successors == 1) {
606 IRBuilder<> Builder(BB->getFirstInsertionPt());
607 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
609 Value *Count = Builder.CreateLoad(Counter);
610 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
611 Builder.CreateStore(Count, Counter);
612 } else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
613 IRBuilder<> Builder(BI);
614 Value *Sel = Builder.CreateSelect(BI->getCondition(),
615 Builder.getInt64(Edge),
616 Builder.getInt64(Edge + 1));
617 SmallVector<Value *, 2> Idx;
618 Idx.push_back(Builder.getInt64(0));
620 Value *Counter = Builder.CreateInBoundsGEP(Counters, Idx);
621 Value *Count = Builder.CreateLoad(Counter);
622 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
623 Builder.CreateStore(Count, Counter);
625 ComplexEdgePreds.insert(BB);
626 for (int i = 0; i != Successors; ++i)
627 ComplexEdgeSuccs.insert(TI->getSuccessor(i));
634 if (!ComplexEdgePreds.empty()) {
635 GlobalVariable *EdgeTable =
636 buildEdgeLookupTable(F, Counters,
637 ComplexEdgePreds, ComplexEdgeSuccs);
638 GlobalVariable *EdgeState = getEdgeStateValue();
640 for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
641 IRBuilder<> Builder(ComplexEdgePreds[i + 1]->getFirstInsertionPt());
642 Builder.CreateStore(Builder.getInt32(i), EdgeState);
645 for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
646 // Call runtime to perform increment.
647 IRBuilder<> Builder(ComplexEdgeSuccs[i+1]->getFirstInsertionPt());
648 Value *CounterPtrArray =
649 Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
650 i * ComplexEdgePreds.size());
652 // Build code to increment the counter.
653 InsertIndCounterIncrCode = true;
654 Builder.CreateCall2(getIncrementIndirectCounterFunc(),
655 EdgeState, CounterPtrArray);
660 Function *WriteoutF = insertCounterWriteout(CountersBySP);
661 Function *FlushF = insertFlush(CountersBySP);
663 // Create a small bit of code that registers the "__llvm_gcov_writeout" to
664 // be executed at exit and the "__llvm_gcov_flush" function to be executed
665 // when "__gcov_flush" is called.
666 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
667 Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
668 "__llvm_gcov_init", M);
669 F->setUnnamedAddr(true);
670 F->setLinkage(GlobalValue::InternalLinkage);
671 F->addFnAttr(Attribute::NoInline);
672 if (Options.NoRedZone)
673 F->addFnAttr(Attribute::NoRedZone);
675 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
676 IRBuilder<> Builder(BB);
678 FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
680 PointerType::get(FTy, 0),
681 PointerType::get(FTy, 0)
683 FTy = FunctionType::get(Builder.getVoidTy(), Params, false);
685 // Initialize the environment and register the local writeout and flush
687 Constant *GCOVInit = M->getOrInsertFunction("llvm_gcov_init", FTy);
688 Builder.CreateCall2(GCOVInit, WriteoutF, FlushF);
689 Builder.CreateRetVoid();
691 appendToGlobalCtors(*M, F, 0);
694 if (InsertIndCounterIncrCode)
695 insertIndirectCounterIncrement();
700 // All edges with successors that aren't branches are "complex", because it
701 // requires complex logic to pick which counter to update.
702 GlobalVariable *GCOVProfiler::buildEdgeLookupTable(
704 GlobalVariable *Counters,
705 const UniqueVector<BasicBlock *> &Preds,
706 const UniqueVector<BasicBlock *> &Succs) {
707 // TODO: support invoke, threads. We rely on the fact that nothing can modify
708 // the whole-Module pred edge# between the time we set it and the time we next
709 // read it. Threads and invoke make this untrue.
711 // emit [(succs * preds) x i64*], logically [succ x [pred x i64*]].
712 size_t TableSize = Succs.size() * Preds.size();
713 Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
714 ArrayType *EdgeTableTy = ArrayType::get(Int64PtrTy, TableSize);
716 std::unique_ptr<Constant * []> EdgeTable(new Constant *[TableSize]);
717 Constant *NullValue = Constant::getNullValue(Int64PtrTy);
718 for (size_t i = 0; i != TableSize; ++i)
719 EdgeTable[i] = NullValue;
722 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
723 TerminatorInst *TI = BB->getTerminator();
724 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
725 if (Successors > 1 && !isa<BranchInst>(TI) && !isa<ReturnInst>(TI)) {
726 for (int i = 0; i != Successors; ++i) {
727 BasicBlock *Succ = TI->getSuccessor(i);
728 IRBuilder<> Builder(Succ);
729 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
731 EdgeTable[((Succs.idFor(Succ)-1) * Preds.size()) +
732 (Preds.idFor(BB)-1)] = cast<Constant>(Counter);
738 ArrayRef<Constant*> V(&EdgeTable[0], TableSize);
739 GlobalVariable *EdgeTableGV =
741 *M, EdgeTableTy, true, GlobalValue::InternalLinkage,
742 ConstantArray::get(EdgeTableTy, V),
743 "__llvm_gcda_edge_table");
744 EdgeTableGV->setUnnamedAddr(true);
748 Constant *GCOVProfiler::getStartFileFunc() {
750 Type::getInt8PtrTy(*Ctx), // const char *orig_filename
751 Type::getInt8PtrTy(*Ctx), // const char version[4]
752 Type::getInt32Ty(*Ctx), // uint32_t checksum
754 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
755 return M->getOrInsertFunction("llvm_gcda_start_file", FTy);
758 Constant *GCOVProfiler::getIncrementIndirectCounterFunc() {
759 Type *Int32Ty = Type::getInt32Ty(*Ctx);
760 Type *Int64Ty = Type::getInt64Ty(*Ctx);
762 Int32Ty->getPointerTo(), // uint32_t *predecessor
763 Int64Ty->getPointerTo()->getPointerTo() // uint64_t **counters
765 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
766 return M->getOrInsertFunction("__llvm_gcov_indirect_counter_increment", FTy);
769 Constant *GCOVProfiler::getEmitFunctionFunc() {
771 Type::getInt32Ty(*Ctx), // uint32_t ident
772 Type::getInt8PtrTy(*Ctx), // const char *function_name
773 Type::getInt32Ty(*Ctx), // uint32_t func_checksum
774 Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
775 Type::getInt32Ty(*Ctx), // uint32_t cfg_checksum
777 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
778 return M->getOrInsertFunction("llvm_gcda_emit_function", FTy);
781 Constant *GCOVProfiler::getEmitArcsFunc() {
783 Type::getInt32Ty(*Ctx), // uint32_t num_counters
784 Type::getInt64PtrTy(*Ctx), // uint64_t *counters
786 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
787 return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy);
790 Constant *GCOVProfiler::getSummaryInfoFunc() {
791 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
792 return M->getOrInsertFunction("llvm_gcda_summary_info", FTy);
795 Constant *GCOVProfiler::getDeleteWriteoutFunctionListFunc() {
796 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
797 return M->getOrInsertFunction("llvm_delete_writeout_function_list", FTy);
800 Constant *GCOVProfiler::getDeleteFlushFunctionListFunc() {
801 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
802 return M->getOrInsertFunction("llvm_delete_flush_function_list", FTy);
805 Constant *GCOVProfiler::getEndFileFunc() {
806 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
807 return M->getOrInsertFunction("llvm_gcda_end_file", FTy);
810 GlobalVariable *GCOVProfiler::getEdgeStateValue() {
811 GlobalVariable *GV = M->getGlobalVariable("__llvm_gcov_global_state_pred");
813 GV = new GlobalVariable(*M, Type::getInt32Ty(*Ctx), false,
814 GlobalValue::InternalLinkage,
815 ConstantInt::get(Type::getInt32Ty(*Ctx),
817 "__llvm_gcov_global_state_pred");
818 GV->setUnnamedAddr(true);
823 Function *GCOVProfiler::insertCounterWriteout(
824 ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
825 FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
826 Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
828 WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
829 "__llvm_gcov_writeout", M);
830 WriteoutF->setUnnamedAddr(true);
831 WriteoutF->addFnAttr(Attribute::NoInline);
832 if (Options.NoRedZone)
833 WriteoutF->addFnAttr(Attribute::NoRedZone);
835 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
836 IRBuilder<> Builder(BB);
838 Constant *StartFile = getStartFileFunc();
839 Constant *EmitFunction = getEmitFunctionFunc();
840 Constant *EmitArcs = getEmitArcsFunc();
841 Constant *SummaryInfo = getSummaryInfoFunc();
842 Constant *EndFile = getEndFileFunc();
844 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
846 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
847 DICompileUnit CU(CU_Nodes->getOperand(i));
848 std::string FilenameGcda = mangleName(CU, "gcda");
849 uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
850 Builder.CreateCall3(StartFile,
851 Builder.CreateGlobalStringPtr(FilenameGcda),
852 Builder.CreateGlobalStringPtr(ReversedVersion),
853 Builder.getInt32(CfgChecksum));
854 for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
855 DISubprogram SP(CountersBySP[j].second);
856 uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
858 EmitFunction, Builder.getInt32(j),
859 Options.FunctionNamesInData ?
860 Builder.CreateGlobalStringPtr(getFunctionName(SP)) :
861 Constant::getNullValue(Builder.getInt8PtrTy()),
862 Builder.getInt32(FuncChecksum),
863 Builder.getInt8(Options.UseCfgChecksum),
864 Builder.getInt32(CfgChecksum));
866 GlobalVariable *GV = CountersBySP[j].first;
868 cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
869 Builder.CreateCall2(EmitArcs,
870 Builder.getInt32(Arcs),
871 Builder.CreateConstGEP2_64(GV, 0, 0));
873 Builder.CreateCall(SummaryInfo);
874 Builder.CreateCall(EndFile);
878 Builder.CreateRetVoid();
882 void GCOVProfiler::insertIndirectCounterIncrement() {
884 cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
885 Fn->setUnnamedAddr(true);
886 Fn->setLinkage(GlobalValue::InternalLinkage);
887 Fn->addFnAttr(Attribute::NoInline);
888 if (Options.NoRedZone)
889 Fn->addFnAttr(Attribute::NoRedZone);
891 // Create basic blocks for function.
892 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", Fn);
893 IRBuilder<> Builder(BB);
895 BasicBlock *PredNotNegOne = BasicBlock::Create(*Ctx, "", Fn);
896 BasicBlock *CounterEnd = BasicBlock::Create(*Ctx, "", Fn);
897 BasicBlock *Exit = BasicBlock::Create(*Ctx, "exit", Fn);
899 // uint32_t pred = *predecessor;
900 // if (pred == 0xffffffff) return;
901 Argument *Arg = Fn->arg_begin();
902 Arg->setName("predecessor");
903 Value *Pred = Builder.CreateLoad(Arg, "pred");
904 Value *Cond = Builder.CreateICmpEQ(Pred, Builder.getInt32(0xffffffff));
905 BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
907 Builder.SetInsertPoint(PredNotNegOne);
909 // uint64_t *counter = counters[pred];
910 // if (!counter) return;
911 Value *ZExtPred = Builder.CreateZExt(Pred, Builder.getInt64Ty());
912 Arg = std::next(Fn->arg_begin());
913 Arg->setName("counters");
914 Value *GEP = Builder.CreateGEP(Arg, ZExtPred);
915 Value *Counter = Builder.CreateLoad(GEP, "counter");
916 Cond = Builder.CreateICmpEQ(Counter,
917 Constant::getNullValue(
918 Builder.getInt64Ty()->getPointerTo()));
919 Builder.CreateCondBr(Cond, Exit, CounterEnd);
922 Builder.SetInsertPoint(CounterEnd);
923 Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
924 Builder.getInt64(1));
925 Builder.CreateStore(Add, Counter);
926 Builder.CreateBr(Exit);
928 // Fill in the exit block.
929 Builder.SetInsertPoint(Exit);
930 Builder.CreateRetVoid();
933 Function *GCOVProfiler::
934 insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
935 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
936 Function *FlushF = M->getFunction("__llvm_gcov_flush");
938 FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
939 "__llvm_gcov_flush", M);
941 FlushF->setLinkage(GlobalValue::InternalLinkage);
942 FlushF->setUnnamedAddr(true);
943 FlushF->addFnAttr(Attribute::NoInline);
944 if (Options.NoRedZone)
945 FlushF->addFnAttr(Attribute::NoRedZone);
947 BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
949 // Write out the current counters.
950 Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
951 assert(WriteoutF && "Need to create the writeout function first!");
953 IRBuilder<> Builder(Entry);
954 Builder.CreateCall(WriteoutF);
956 // Zero out the counters.
957 for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
958 I = CountersBySP.begin(), E = CountersBySP.end();
960 GlobalVariable *GV = I->first;
961 Constant *Null = Constant::getNullValue(GV->getType()->getElementType());
962 Builder.CreateStore(Null, GV);
965 Type *RetTy = FlushF->getReturnType();
966 if (RetTy == Type::getVoidTy(*Ctx))
967 Builder.CreateRetVoid();
968 else if (RetTy->isIntegerTy())
969 // Used if __llvm_gcov_flush was implicitly declared.
970 Builder.CreateRet(ConstantInt::get(RetTy, 0));
972 report_fatal_error("invalid return type for __llvm_gcov_flush");