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 #define DEBUG_TYPE "insert-gcov-profiling"
19 #include "llvm/Transforms/Instrumentation.h"
20 #include "ProfilingUtils.h"
21 #include "llvm/ADT/DenseMap.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/ADT/Statistic.h"
24 #include "llvm/ADT/StringExtras.h"
25 #include "llvm/ADT/StringMap.h"
26 #include "llvm/ADT/UniqueVector.h"
27 #include "llvm/DebugInfo.h"
28 #include "llvm/IR/IRBuilder.h"
29 #include "llvm/IR/Instructions.h"
30 #include "llvm/IR/Module.h"
31 #include "llvm/Pass.h"
32 #include "llvm/Support/CommandLine.h"
33 #include "llvm/Support/Debug.h"
34 #include "llvm/Support/DebugLoc.h"
35 #include "llvm/Support/InstIterator.h"
36 #include "llvm/Support/PathV2.h"
37 #include "llvm/Support/raw_ostream.h"
38 #include "llvm/Transforms/Utils/ModuleUtils.h"
43 static cl::opt<std::string>
44 DefaultGCOVVersion("default-gcov-version", cl::init("402*"), cl::Hidden,
47 GCOVOptions GCOVOptions::getDefault() {
49 Options.EmitNotes = true;
50 Options.EmitData = true;
51 Options.UseCfgChecksum = false;
52 Options.NoRedZone = false;
53 Options.FunctionNamesInData = true;
55 if (DefaultGCOVVersion.size() != 4) {
56 llvm::report_fatal_error(std::string("Invalid -default-gcov-version: ") +
59 memcpy(Options.Version, DefaultGCOVVersion.c_str(), 4);
64 class GCOVProfiler : public ModulePass {
67 GCOVProfiler() : ModulePass(ID), Options(GCOVOptions::getDefault()) {
68 ReversedVersion[0] = Options.Version[3];
69 ReversedVersion[1] = Options.Version[2];
70 ReversedVersion[2] = Options.Version[1];
71 ReversedVersion[3] = Options.Version[0];
72 ReversedVersion[4] = '\0';
73 initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
75 GCOVProfiler(const GCOVOptions &Options) : ModulePass(ID), Options(Options){
76 assert((Options.EmitNotes || Options.EmitData) &&
77 "GCOVProfiler asked to do nothing?");
78 ReversedVersion[0] = Options.Version[3];
79 ReversedVersion[1] = Options.Version[2];
80 ReversedVersion[2] = Options.Version[1];
81 ReversedVersion[3] = Options.Version[0];
82 ReversedVersion[4] = '\0';
83 initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
85 virtual const char *getPassName() const {
86 return "GCOV Profiler";
90 bool runOnModule(Module &M);
92 // Create the .gcno files for the Module based on DebugInfo.
93 void emitProfileNotes();
95 // Modify the program to track transitions along edges and call into the
96 // profiling runtime to emit .gcda files when run.
97 bool emitProfileArcs();
99 // Get pointers to the functions in the runtime library.
100 Constant *getStartFileFunc();
101 Constant *getIncrementIndirectCounterFunc();
102 Constant *getEmitFunctionFunc();
103 Constant *getEmitArcsFunc();
104 Constant *getEndFileFunc();
106 // Create or retrieve an i32 state value that is used to represent the
107 // pred block number for certain non-trivial edges.
108 GlobalVariable *getEdgeStateValue();
110 // Produce a table of pointers to counters, by predecessor and successor
112 GlobalVariable *buildEdgeLookupTable(Function *F,
113 GlobalVariable *Counter,
114 const UniqueVector<BasicBlock *>&Preds,
115 const UniqueVector<BasicBlock*>&Succs);
117 // Add the function to write out all our counters to the global destructor
119 void insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
120 void insertIndirectCounterIncrement();
121 void insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
123 std::string mangleName(DICompileUnit CU, const char *NewStem);
127 // Reversed, NUL-terminated copy of Options.Version.
128 char ReversedVersion[5];
135 char GCOVProfiler::ID = 0;
136 INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling",
137 "Insert instrumentation for GCOV profiling", false, false)
139 ModulePass *llvm::createGCOVProfilerPass(const GCOVOptions &Options) {
140 return new GCOVProfiler(Options);
146 static const char *LinesTag;
147 static const char *FunctionTag;
148 static const char *BlockTag;
149 static const char *EdgeTag;
153 void writeBytes(const char *Bytes, int Size) {
154 os->write(Bytes, Size);
157 void write(uint32_t i) {
158 writeBytes(reinterpret_cast<char*>(&i), 4);
161 // Returns the length measured in 4-byte blocks that will be used to
162 // represent this string in a GCOV file
163 unsigned lengthOfGCOVString(StringRef s) {
164 // A GCOV string is a length, followed by a NUL, then between 0 and 3 NULs
165 // padding out to the next 4-byte word. The length is measured in 4-byte
166 // words including padding, not bytes of actual string.
167 return (s.size() / 4) + 1;
170 void writeGCOVString(StringRef s) {
171 uint32_t Len = lengthOfGCOVString(s);
173 writeBytes(s.data(), s.size());
175 // Write 1 to 4 bytes of NUL padding.
176 assert((unsigned)(4 - (s.size() % 4)) > 0);
177 assert((unsigned)(4 - (s.size() % 4)) <= 4);
178 writeBytes("\0\0\0\0", 4 - (s.size() % 4));
183 const char *GCOVRecord::LinesTag = "\0\0\x45\x01";
184 const char *GCOVRecord::FunctionTag = "\0\0\0\1";
185 const char *GCOVRecord::BlockTag = "\0\0\x41\x01";
186 const char *GCOVRecord::EdgeTag = "\0\0\x43\x01";
191 // Constructed only by requesting it from a GCOVBlock, this object stores a
192 // list of line numbers and a single filename, representing lines that belong
194 class GCOVLines : public GCOVRecord {
196 void addLine(uint32_t Line) {
197 Lines.push_back(Line);
201 // Here 2 = 1 for string length + 1 for '0' id#.
202 return lengthOfGCOVString(Filename) + 2 + Lines.size();
207 writeGCOVString(Filename);
208 for (int i = 0, e = Lines.size(); i != e; ++i)
212 GCOVLines(StringRef F, raw_ostream *os)
219 SmallVector<uint32_t, 32> Lines;
222 // Represent a basic block in GCOV. Each block has a unique number in the
223 // function, number of lines belonging to each block, and a set of edges to
225 class GCOVBlock : public GCOVRecord {
227 GCOVLines &getFile(StringRef Filename) {
228 GCOVLines *&Lines = LinesByFile[Filename];
230 Lines = new GCOVLines(Filename, os);
235 void addEdge(GCOVBlock &Successor) {
236 OutEdges.push_back(&Successor);
241 for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
242 E = LinesByFile.end(); I != E; ++I) {
243 Len += I->second->length();
246 writeBytes(LinesTag, 4);
249 for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
250 E = LinesByFile.end(); I != E; ++I)
251 I->second->writeOut();
257 DeleteContainerSeconds(LinesByFile);
261 friend class GCOVFunction;
263 GCOVBlock(uint32_t Number, raw_ostream *os)
269 StringMap<GCOVLines *> LinesByFile;
270 SmallVector<GCOVBlock *, 4> OutEdges;
273 // A function has a unique identifier, a checksum (we leave as zero) and a
274 // set of blocks and a map of edges between blocks. This is the only GCOV
275 // object users can construct, the blocks and lines will be rooted here.
276 class GCOVFunction : public GCOVRecord {
278 GCOVFunction(DISubprogram SP, raw_ostream *os, uint32_t Ident,
279 bool UseCfgChecksum) {
282 Function *F = SP.getFunction();
283 DEBUG(dbgs() << "Function: " << F->getName() << "\n");
285 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
286 Blocks[BB] = new GCOVBlock(i++, os);
288 ReturnBlock = new GCOVBlock(i++, os);
290 writeBytes(FunctionTag, 4);
291 uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(SP.getName()) +
292 1 + lengthOfGCOVString(SP.getFilename()) + 1;
297 write(0); // lineno checksum
299 write(0); // cfg checksum
300 writeGCOVString(SP.getName());
301 writeGCOVString(SP.getFilename());
302 write(SP.getLineNumber());
306 DeleteContainerSeconds(Blocks);
310 GCOVBlock &getBlock(BasicBlock *BB) {
314 GCOVBlock &getReturnBlock() {
319 // Emit count of blocks.
320 writeBytes(BlockTag, 4);
321 write(Blocks.size() + 1);
322 for (int i = 0, e = Blocks.size() + 1; i != e; ++i) {
323 write(0); // No flags on our blocks.
325 DEBUG(dbgs() << Blocks.size() << " blocks.\n");
327 // Emit edges between blocks.
328 for (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(),
329 E = Blocks.end(); I != E; ++I) {
330 GCOVBlock &Block = *I->second;
331 if (Block.OutEdges.empty()) continue;
333 writeBytes(EdgeTag, 4);
334 write(Block.OutEdges.size() * 2 + 1);
336 for (int i = 0, e = Block.OutEdges.size(); i != e; ++i) {
337 DEBUG(dbgs() << Block.Number << " -> " << Block.OutEdges[i]->Number
339 write(Block.OutEdges[i]->Number);
340 write(0); // no flags
344 // Emit lines for each block.
345 for (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(),
346 E = Blocks.end(); I != E; ++I) {
347 I->second->writeOut();
352 DenseMap<BasicBlock *, GCOVBlock *> Blocks;
353 GCOVBlock *ReturnBlock;
357 std::string GCOVProfiler::mangleName(DICompileUnit CU, const char *NewStem) {
358 if (NamedMDNode *GCov = M->getNamedMetadata("llvm.gcov")) {
359 for (int i = 0, e = GCov->getNumOperands(); i != e; ++i) {
360 MDNode *N = GCov->getOperand(i);
361 if (N->getNumOperands() != 2) continue;
362 MDString *GCovFile = dyn_cast<MDString>(N->getOperand(0));
363 MDNode *CompileUnit = dyn_cast<MDNode>(N->getOperand(1));
364 if (!GCovFile || !CompileUnit) continue;
365 if (CompileUnit == CU) {
366 SmallString<128> Filename = GCovFile->getString();
367 sys::path::replace_extension(Filename, NewStem);
368 return Filename.str();
373 SmallString<128> Filename = CU.getFilename();
374 sys::path::replace_extension(Filename, NewStem);
375 return sys::path::filename(Filename.str());
378 bool GCOVProfiler::runOnModule(Module &M) {
380 Ctx = &M.getContext();
382 if (Options.EmitNotes) emitProfileNotes();
383 if (Options.EmitData) return emitProfileArcs();
387 void GCOVProfiler::emitProfileNotes() {
388 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
389 if (!CU_Nodes) return;
391 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
392 // Each compile unit gets its own .gcno file. This means that whether we run
393 // this pass over the original .o's as they're produced, or run it after
394 // LTO, we'll generate the same .gcno files.
396 DICompileUnit CU(CU_Nodes->getOperand(i));
397 std::string ErrorInfo;
398 outs() << "outputting gcno to: " << mangleName(CU, "gcno") << "\n";
399 raw_fd_ostream out(mangleName(CU, "gcno").c_str(), ErrorInfo,
400 raw_fd_ostream::F_Binary);
401 out.write("oncg", 4);
402 out.write(ReversedVersion, 4);
403 out.write("MVLL", 4);
405 DIArray SPs = CU.getSubprograms();
406 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
407 DISubprogram SP(SPs.getElement(i));
408 if (!SP.Verify()) continue;
410 Function *F = SP.getFunction();
412 GCOVFunction Func(SP, &out, i, Options.UseCfgChecksum);
414 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
415 GCOVBlock &Block = Func.getBlock(BB);
416 TerminatorInst *TI = BB->getTerminator();
417 if (int successors = TI->getNumSuccessors()) {
418 for (int i = 0; i != successors; ++i) {
419 Block.addEdge(Func.getBlock(TI->getSuccessor(i)));
421 } else if (isa<ReturnInst>(TI)) {
422 Block.addEdge(Func.getReturnBlock());
426 for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
428 const DebugLoc &Loc = I->getDebugLoc();
429 if (Loc.isUnknown()) continue;
430 if (Line == Loc.getLine()) continue;
431 Line = Loc.getLine();
432 if (SP != getDISubprogram(Loc.getScope(*Ctx))) continue;
434 GCOVLines &Lines = Block.getFile(SP.getFilename());
435 Lines.addLine(Loc.getLine());
440 out.write("\0\0\0\0\0\0\0\0", 8); // EOF
445 bool GCOVProfiler::emitProfileArcs() {
446 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
447 if (!CU_Nodes) return false;
450 bool InsertIndCounterIncrCode = false;
451 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
452 DICompileUnit CU(CU_Nodes->getOperand(i));
453 DIArray SPs = CU.getSubprograms();
454 SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
455 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
456 DISubprogram SP(SPs.getElement(i));
457 if (!SP.Verify()) continue;
458 Function *F = SP.getFunction();
460 if (!Result) Result = true;
462 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
463 TerminatorInst *TI = BB->getTerminator();
464 if (isa<ReturnInst>(TI))
467 Edges += TI->getNumSuccessors();
470 ArrayType *CounterTy =
471 ArrayType::get(Type::getInt64Ty(*Ctx), Edges);
472 GlobalVariable *Counters =
473 new GlobalVariable(*M, CounterTy, false,
474 GlobalValue::InternalLinkage,
475 Constant::getNullValue(CounterTy),
477 CountersBySP.push_back(std::make_pair(Counters, (MDNode*)SP));
479 UniqueVector<BasicBlock *> ComplexEdgePreds;
480 UniqueVector<BasicBlock *> ComplexEdgeSuccs;
483 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
484 TerminatorInst *TI = BB->getTerminator();
485 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
487 IRBuilder<> Builder(TI);
489 if (Successors == 1) {
490 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
492 Value *Count = Builder.CreateLoad(Counter);
493 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
494 Builder.CreateStore(Count, Counter);
495 } else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
496 Value *Sel = Builder.CreateSelect(BI->getCondition(),
497 Builder.getInt64(Edge),
498 Builder.getInt64(Edge + 1));
499 SmallVector<Value *, 2> Idx;
500 Idx.push_back(Builder.getInt64(0));
502 Value *Counter = Builder.CreateInBoundsGEP(Counters, Idx);
503 Value *Count = Builder.CreateLoad(Counter);
504 Count = Builder.CreateAdd(Count, Builder.getInt64(1));
505 Builder.CreateStore(Count, Counter);
507 ComplexEdgePreds.insert(BB);
508 for (int i = 0; i != Successors; ++i)
509 ComplexEdgeSuccs.insert(TI->getSuccessor(i));
515 if (!ComplexEdgePreds.empty()) {
516 GlobalVariable *EdgeTable =
517 buildEdgeLookupTable(F, Counters,
518 ComplexEdgePreds, ComplexEdgeSuccs);
519 GlobalVariable *EdgeState = getEdgeStateValue();
521 for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
522 IRBuilder<> Builder(ComplexEdgePreds[i+1]->getTerminator());
523 Builder.CreateStore(Builder.getInt32(i), EdgeState);
525 for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
526 // call runtime to perform increment
527 BasicBlock::iterator InsertPt =
528 ComplexEdgeSuccs[i+1]->getFirstInsertionPt();
529 IRBuilder<> Builder(InsertPt);
530 Value *CounterPtrArray =
531 Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
532 i * ComplexEdgePreds.size());
534 // Build code to increment the counter.
535 InsertIndCounterIncrCode = true;
536 Builder.CreateCall2(getIncrementIndirectCounterFunc(),
537 EdgeState, CounterPtrArray);
542 insertCounterWriteout(CountersBySP);
543 insertFlush(CountersBySP);
546 if (InsertIndCounterIncrCode)
547 insertIndirectCounterIncrement();
552 // All edges with successors that aren't branches are "complex", because it
553 // requires complex logic to pick which counter to update.
554 GlobalVariable *GCOVProfiler::buildEdgeLookupTable(
556 GlobalVariable *Counters,
557 const UniqueVector<BasicBlock *> &Preds,
558 const UniqueVector<BasicBlock *> &Succs) {
559 // TODO: support invoke, threads. We rely on the fact that nothing can modify
560 // the whole-Module pred edge# between the time we set it and the time we next
561 // read it. Threads and invoke make this untrue.
563 // emit [(succs * preds) x i64*], logically [succ x [pred x i64*]].
564 size_t TableSize = Succs.size() * Preds.size();
565 Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
566 ArrayType *EdgeTableTy = ArrayType::get(Int64PtrTy, TableSize);
568 OwningArrayPtr<Constant *> EdgeTable(new Constant*[TableSize]);
569 Constant *NullValue = Constant::getNullValue(Int64PtrTy);
570 for (size_t i = 0; i != TableSize; ++i)
571 EdgeTable[i] = NullValue;
574 for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
575 TerminatorInst *TI = BB->getTerminator();
576 int Successors = isa<ReturnInst>(TI) ? 1 : TI->getNumSuccessors();
577 if (Successors > 1 && !isa<BranchInst>(TI) && !isa<ReturnInst>(TI)) {
578 for (int i = 0; i != Successors; ++i) {
579 BasicBlock *Succ = TI->getSuccessor(i);
580 IRBuilder<> Builder(Succ);
581 Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
583 EdgeTable[((Succs.idFor(Succ)-1) * Preds.size()) +
584 (Preds.idFor(BB)-1)] = cast<Constant>(Counter);
590 ArrayRef<Constant*> V(&EdgeTable[0], TableSize);
591 GlobalVariable *EdgeTableGV =
593 *M, EdgeTableTy, true, GlobalValue::InternalLinkage,
594 ConstantArray::get(EdgeTableTy, V),
595 "__llvm_gcda_edge_table");
596 EdgeTableGV->setUnnamedAddr(true);
600 Constant *GCOVProfiler::getStartFileFunc() {
602 Type::getInt8PtrTy(*Ctx), // const char *orig_filename
603 Type::getInt8PtrTy(*Ctx), // const char version[4]
605 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
606 return M->getOrInsertFunction("llvm_gcda_start_file", FTy);
609 Constant *GCOVProfiler::getIncrementIndirectCounterFunc() {
610 Type *Int32Ty = Type::getInt32Ty(*Ctx);
611 Type *Int64Ty = Type::getInt64Ty(*Ctx);
613 Int32Ty->getPointerTo(), // uint32_t *predecessor
614 Int64Ty->getPointerTo()->getPointerTo() // uint64_t **counters
616 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
617 return M->getOrInsertFunction("__llvm_gcov_indirect_counter_increment", FTy);
620 Constant *GCOVProfiler::getEmitFunctionFunc() {
622 Type::getInt32Ty(*Ctx), // uint32_t ident
623 Type::getInt8PtrTy(*Ctx), // const char *function_name
624 Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
626 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
627 return M->getOrInsertFunction("llvm_gcda_emit_function", FTy);
630 Constant *GCOVProfiler::getEmitArcsFunc() {
632 Type::getInt32Ty(*Ctx), // uint32_t num_counters
633 Type::getInt64PtrTy(*Ctx), // uint64_t *counters
635 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, false);
636 return M->getOrInsertFunction("llvm_gcda_emit_arcs", FTy);
639 Constant *GCOVProfiler::getEndFileFunc() {
640 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
641 return M->getOrInsertFunction("llvm_gcda_end_file", FTy);
644 GlobalVariable *GCOVProfiler::getEdgeStateValue() {
645 GlobalVariable *GV = M->getGlobalVariable("__llvm_gcov_global_state_pred");
647 GV = new GlobalVariable(*M, Type::getInt32Ty(*Ctx), false,
648 GlobalValue::InternalLinkage,
649 ConstantInt::get(Type::getInt32Ty(*Ctx),
651 "__llvm_gcov_global_state_pred");
652 GV->setUnnamedAddr(true);
657 void GCOVProfiler::insertCounterWriteout(
658 ArrayRef<std::pair<GlobalVariable *, MDNode *> > CountersBySP) {
659 FunctionType *WriteoutFTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
660 Function *WriteoutF = M->getFunction("__llvm_gcov_writeout");
662 WriteoutF = Function::Create(WriteoutFTy, GlobalValue::InternalLinkage,
663 "__llvm_gcov_writeout", M);
664 WriteoutF->setUnnamedAddr(true);
665 WriteoutF->addFnAttr(Attribute::NoInline);
666 if (Options.NoRedZone)
667 WriteoutF->addFnAttr(Attribute::NoRedZone);
669 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
670 IRBuilder<> Builder(BB);
672 Constant *StartFile = getStartFileFunc();
673 Constant *EmitFunction = getEmitFunctionFunc();
674 Constant *EmitArcs = getEmitArcsFunc();
675 Constant *EndFile = getEndFileFunc();
677 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
679 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
680 DICompileUnit CU(CU_Nodes->getOperand(i));
681 std::string FilenameGcda = mangleName(CU, "gcda");
682 Builder.CreateCall2(StartFile,
683 Builder.CreateGlobalStringPtr(FilenameGcda),
684 Builder.CreateGlobalStringPtr(ReversedVersion));
685 for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
686 DISubprogram SP(CountersBySP[j].second);
687 Builder.CreateCall3(EmitFunction,
689 Options.FunctionNamesInData ?
690 Builder.CreateGlobalStringPtr(SP.getName()) :
691 Constant::getNullValue(Builder.getInt8PtrTy()),
692 Builder.getInt8(Options.UseCfgChecksum));
694 GlobalVariable *GV = CountersBySP[j].first;
696 cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
697 Builder.CreateCall2(EmitArcs,
698 Builder.getInt32(Arcs),
699 Builder.CreateConstGEP2_64(GV, 0, 0));
701 Builder.CreateCall(EndFile);
704 Builder.CreateRetVoid();
706 // Create a small bit of code that registers the "__llvm_gcov_writeout"
707 // function to be executed at exit.
708 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
709 Function *F = Function::Create(FTy, GlobalValue::InternalLinkage,
710 "__llvm_gcov_init", M);
711 F->setUnnamedAddr(true);
712 F->setLinkage(GlobalValue::InternalLinkage);
713 F->addFnAttr(Attribute::NoInline);
714 if (Options.NoRedZone)
715 F->addFnAttr(Attribute::NoRedZone);
717 BB = BasicBlock::Create(*Ctx, "entry", F);
718 Builder.SetInsertPoint(BB);
720 FTy = FunctionType::get(Builder.getInt32Ty(),
721 PointerType::get(FTy, 0), false);
722 Constant *AtExitFn = M->getOrInsertFunction("atexit", FTy);
723 Builder.CreateCall(AtExitFn, WriteoutF);
724 Builder.CreateRetVoid();
726 appendToGlobalCtors(*M, F, 0);
729 void GCOVProfiler::insertIndirectCounterIncrement() {
731 cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
732 Fn->setUnnamedAddr(true);
733 Fn->setLinkage(GlobalValue::InternalLinkage);
734 Fn->addFnAttr(Attribute::NoInline);
735 if (Options.NoRedZone)
736 Fn->addFnAttr(Attribute::NoRedZone);
738 // Create basic blocks for function.
739 BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", Fn);
740 IRBuilder<> Builder(BB);
742 BasicBlock *PredNotNegOne = BasicBlock::Create(*Ctx, "", Fn);
743 BasicBlock *CounterEnd = BasicBlock::Create(*Ctx, "", Fn);
744 BasicBlock *Exit = BasicBlock::Create(*Ctx, "exit", Fn);
746 // uint32_t pred = *predecessor;
747 // if (pred == 0xffffffff) return;
748 Argument *Arg = Fn->arg_begin();
749 Arg->setName("predecessor");
750 Value *Pred = Builder.CreateLoad(Arg, "pred");
751 Value *Cond = Builder.CreateICmpEQ(Pred, Builder.getInt32(0xffffffff));
752 BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
754 Builder.SetInsertPoint(PredNotNegOne);
756 // uint64_t *counter = counters[pred];
757 // if (!counter) return;
758 Value *ZExtPred = Builder.CreateZExt(Pred, Builder.getInt64Ty());
759 Arg = llvm::next(Fn->arg_begin());
760 Arg->setName("counters");
761 Value *GEP = Builder.CreateGEP(Arg, ZExtPred);
762 Value *Counter = Builder.CreateLoad(GEP, "counter");
763 Cond = Builder.CreateICmpEQ(Counter,
764 Constant::getNullValue(
765 Builder.getInt64Ty()->getPointerTo()));
766 Builder.CreateCondBr(Cond, Exit, CounterEnd);
769 Builder.SetInsertPoint(CounterEnd);
770 Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
771 Builder.getInt64(1));
772 Builder.CreateStore(Add, Counter);
773 Builder.CreateBr(Exit);
775 // Fill in the exit block.
776 Builder.SetInsertPoint(Exit);
777 Builder.CreateRetVoid();
781 insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
782 FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
783 Function *FlushF = M->getFunction("__gcov_flush");
785 FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
788 FlushF->setLinkage(GlobalValue::InternalLinkage);
789 FlushF->setUnnamedAddr(true);
790 FlushF->addFnAttr(Attribute::NoInline);
791 if (Options.NoRedZone)
792 FlushF->addFnAttr(Attribute::NoRedZone);
794 BasicBlock *Entry = BasicBlock::Create(*Ctx, "entry", FlushF);
796 // Write out the current counters.
797 Constant *WriteoutF = M->getFunction("__llvm_gcov_writeout");
798 assert(WriteoutF && "Need to create the writeout function first!");
800 IRBuilder<> Builder(Entry);
801 Builder.CreateCall(WriteoutF);
803 // Zero out the counters.
804 for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
805 I = CountersBySP.begin(), E = CountersBySP.end();
807 GlobalVariable *GV = I->first;
808 Constant *Null = Constant::getNullValue(GV->getType()->getElementType());
809 Builder.CreateStore(Null, GV);
812 Type *RetTy = FlushF->getReturnType();
813 if (RetTy == Type::getVoidTy(*Ctx))
814 Builder.CreateRetVoid();
815 else if (RetTy->isIntegerTy())
816 // Used if __gcov_flush was implicitly declared.
817 Builder.CreateRet(ConstantInt::get(RetTy, 0));
819 report_fatal_error("invalid return type for __gcov_flush");