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diff --git a/contrib/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp b/contrib/llvm/lib/Transforms/Instrumentation/GCOVProfiling.cpp
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+//===- 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.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Instrumentation.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Hashing.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/IR/DebugInfo.h"
+#include "llvm/IR/DebugLoc.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/InstIterator.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Utils/ModuleUtils.h"
+#include <algorithm>
+#include <memory>
+#include <string>
+#include <utility>
+using namespace llvm;
+
+#define DEBUG_TYPE "insert-gcov-profiling"
+
+static cl::opt<std::string>
+DefaultGCOVVersion("default-gcov-version", cl::init("402*"), cl::Hidden,
+ cl::ValueRequired);
+static cl::opt<bool> DefaultExitBlockBeforeBody("gcov-exit-block-before-body",
+ cl::init(false), cl::Hidden);
+
+GCOVOptions GCOVOptions::getDefault() {
+ GCOVOptions Options;
+ Options.EmitNotes = true;
+ Options.EmitData = true;
+ Options.UseCfgChecksum = false;
+ Options.NoRedZone = false;
+ Options.FunctionNamesInData = true;
+ Options.ExitBlockBeforeBody = DefaultExitBlockBeforeBody;
+
+ if (DefaultGCOVVersion.size() != 4) {
+ llvm::report_fatal_error(std::string("Invalid -default-gcov-version: ") +
+ DefaultGCOVVersion);
+ }
+ memcpy(Options.Version, DefaultGCOVVersion.c_str(), 4);
+ return Options;
+}
+
+namespace {
+ class GCOVFunction;
+
+ class GCOVProfiler : public ModulePass {
+ public:
+ static char ID;
+ GCOVProfiler() : GCOVProfiler(GCOVOptions::getDefault()) {}
+ GCOVProfiler(const GCOVOptions &Opts) : ModulePass(ID), Options(Opts) {
+ assert((Options.EmitNotes || Options.EmitData) &&
+ "GCOVProfiler asked to do nothing?");
+ ReversedVersion[0] = Options.Version[3];
+ ReversedVersion[1] = Options.Version[2];
+ ReversedVersion[2] = Options.Version[1];
+ ReversedVersion[3] = Options.Version[0];
+ ReversedVersion[4] = '\0';
+ initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
+ }
+ const char *getPassName() const override {
+ return "GCOV Profiler";
+ }
+
+ private:
+ bool runOnModule(Module &M) override;
+
+ // Create the .gcno files for the Module based on DebugInfo.
+ void emitProfileNotes();
+
+ // 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 *getSummaryInfoFunc();
+ Constant *getDeleteWriteoutFunctionListFunc();
+ Constant *getDeleteFlushFunctionListFunc();
+ 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.
+ Function *insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*,
+ MDNode*> >);
+ Function *insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
+ void insertIndirectCounterIncrement();
+
+ std::string mangleName(const DICompileUnit *CU, const char *NewStem);
+
+ GCOVOptions Options;
+
+ // Reversed, NUL-terminated copy of Options.Version.
+ char ReversedVersion[5];
+ // Checksum, produced by hash of EdgeDestinations
+ SmallVector<uint32_t, 4> FileChecksums;
+
+ Module *M;
+ LLVMContext *Ctx;
+ SmallVector<std::unique_ptr<GCOVFunction>, 16> Funcs;
+ };
+} // namespace
+
+char GCOVProfiler::ID = 0;
+INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling",
+ "Insert instrumentation for GCOV profiling", false, false)
+
+ModulePass *llvm::createGCOVProfilerPass(const GCOVOptions &Options) {
+ return new GCOVProfiler(Options);
+}
+
+static StringRef getFunctionName(const DISubprogram *SP) {
+ if (!SP->getLinkageName().empty())
+ return SP->getLinkageName();
+ return SP->getName();
+}
+
+namespace {
+ class GCOVRecord {
+ protected:
+ static const char *const LinesTag;
+ static const char *const FunctionTag;
+ static const char *const BlockTag;
+ static const char *const EdgeTag;
+
+ GCOVRecord() = default;
+
+ 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
+ static 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 *const GCOVRecord::LinesTag = "\0\0\x45\x01";
+ const char *const GCOVRecord::FunctionTag = "\0\0\0\1";
+ const char *const GCOVRecord::BlockTag = "\0\0\x41\x01";
+ const char *const 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) {
+ assert(Line != 0 && "Line zero is not a valid real line number.");
+ Lines.push_back(Line);
+ }
+
+ uint32_t length() const {
+ // 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;
+ SmallVector<StringMapEntry<GCOVLines *> *, 32> SortedLinesByFile;
+ for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
+ E = LinesByFile.end(); I != E; ++I) {
+ Len += I->second->length();
+ SortedLinesByFile.push_back(&*I);
+ }
+
+ writeBytes(LinesTag, 4);
+ write(Len);
+ write(Number);
+
+ std::sort(SortedLinesByFile.begin(), SortedLinesByFile.end(),
+ [](StringMapEntry<GCOVLines *> *LHS,
+ StringMapEntry<GCOVLines *> *RHS) {
+ return LHS->getKey() < RHS->getKey();
+ });
+ for (SmallVectorImpl<StringMapEntry<GCOVLines *> *>::iterator
+ I = SortedLinesByFile.begin(), E = SortedLinesByFile.end();
+ I != E; ++I)
+ (*I)->getValue()->writeOut();
+ write(0);
+ write(0);
+ }
+
+ ~GCOVBlock() {
+ DeleteContainerSeconds(LinesByFile);
+ }
+
+ GCOVBlock(const GCOVBlock &RHS) : GCOVRecord(RHS), Number(RHS.Number) {
+ // Only allow copy before edges and lines have been added. After that,
+ // there are inter-block pointers (eg: edges) that won't take kindly to
+ // blocks being copied or moved around.
+ assert(LinesByFile.empty());
+ assert(OutEdges.empty());
+ }
+
+ 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(const DISubprogram *SP, raw_ostream *os, uint32_t Ident,
+ bool UseCfgChecksum, bool ExitBlockBeforeBody)
+ : SP(SP), Ident(Ident), UseCfgChecksum(UseCfgChecksum), CfgChecksum(0),
+ ReturnBlock(1, os) {
+ this->os = os;
+
+ Function *F = SP->getFunction();
+ DEBUG(dbgs() << "Function: " << getFunctionName(SP) << "\n");
+
+ uint32_t i = 0;
+ for (auto &BB : *F) {
+ // Skip index 1 if it's assigned to the ReturnBlock.
+ if (i == 1 && ExitBlockBeforeBody)
+ ++i;
+ Blocks.insert(std::make_pair(&BB, GCOVBlock(i++, os)));
+ }
+ if (!ExitBlockBeforeBody)
+ ReturnBlock.Number = i;
+
+ std::string FunctionNameAndLine;
+ raw_string_ostream FNLOS(FunctionNameAndLine);
+ FNLOS << getFunctionName(SP) << SP->getLine();
+ FNLOS.flush();
+ FuncChecksum = hash_value(FunctionNameAndLine);
+ }
+
+ GCOVBlock &getBlock(BasicBlock *BB) {
+ return Blocks.find(BB)->second;
+ }
+
+ GCOVBlock &getReturnBlock() {
+ return ReturnBlock;
+ }
+
+ std::string getEdgeDestinations() {
+ std::string EdgeDestinations;
+ raw_string_ostream EDOS(EdgeDestinations);
+ Function *F = Blocks.begin()->first->getParent();
+ for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
+ GCOVBlock &Block = getBlock(I);
+ for (int i = 0, e = Block.OutEdges.size(); i != e; ++i)
+ EDOS << Block.OutEdges[i]->Number;
+ }
+ return EdgeDestinations;
+ }
+
+ uint32_t getFuncChecksum() {
+ return FuncChecksum;
+ }
+
+ void setCfgChecksum(uint32_t Checksum) {
+ CfgChecksum = Checksum;
+ }
+
+ void writeOut() {
+ writeBytes(FunctionTag, 4);
+ uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(getFunctionName(SP)) +
+ 1 + lengthOfGCOVString(SP->getFilename()) + 1;
+ if (UseCfgChecksum)
+ ++BlockLen;
+ write(BlockLen);
+ write(Ident);
+ write(FuncChecksum);
+ if (UseCfgChecksum)
+ write(CfgChecksum);
+ writeGCOVString(getFunctionName(SP));
+ writeGCOVString(SP->getFilename());
+ write(SP->getLine());
+
+ // 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.
+ if (Blocks.empty()) return;
+ Function *F = Blocks.begin()->first->getParent();
+ for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
+ GCOVBlock &Block = getBlock(I);
+ 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 (Function::iterator I = F->begin(), E = F->end(); I != E; ++I) {
+ getBlock(I).writeOut();
+ }
+ }
+
+ private:
+ const DISubprogram *SP;
+ uint32_t Ident;
+ uint32_t FuncChecksum;
+ bool UseCfgChecksum;
+ uint32_t CfgChecksum;
+ DenseMap<BasicBlock *, GCOVBlock> Blocks;
+ GCOVBlock ReturnBlock;
+ };
+} // namespace
+
+std::string GCOVProfiler::mangleName(const 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);
+ StringRef FName = sys::path::filename(Filename);
+ SmallString<128> CurPath;
+ if (sys::fs::current_path(CurPath)) return FName;
+ sys::path::append(CurPath, FName);
+ return CurPath.str();
+}
+
+bool GCOVProfiler::runOnModule(Module &M) {
+ this->M = &M;
+ Ctx = &M.getContext();
+
+ if (Options.EmitNotes) emitProfileNotes();
+ if (Options.EmitData) return emitProfileArcs();
+ return false;
+}
+
+static bool functionHasLines(Function *F) {
+ // Check whether this function actually has any source lines. Not only
+ // do these waste space, they also can crash gcov.
+ for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
+ for (BasicBlock::iterator I = BB->begin(), IE = BB->end();
+ I != IE; ++I) {
+ // Debug intrinsic locations correspond to the location of the
+ // declaration, not necessarily any statements or expressions.
+ if (isa<DbgInfoIntrinsic>(I)) continue;
+
+ const DebugLoc &Loc = I->getDebugLoc();
+ if (!Loc)
+ continue;
+
+ // Artificial lines such as calls to the global constructors.
+ if (Loc.getLine() == 0) continue;
+
+ return true;
+ }
+ }
+ return false;
+}
+
+void GCOVProfiler::emitProfileNotes() {
+ 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.
+
+ auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
+ std::error_code EC;
+ raw_fd_ostream out(mangleName(CU, "gcno"), EC, sys::fs::F_None);
+ std::string EdgeDestinations;
+
+ unsigned FunctionIdent = 0;
+ for (auto *SP : CU->getSubprograms()) {
+ Function *F = SP->getFunction();
+ if (!F) continue;
+ if (!functionHasLines(F)) continue;
+
+ // gcov expects every function to start with an entry block that has a
+ // single successor, so split the entry block to make sure of that.
+ BasicBlock &EntryBlock = F->getEntryBlock();
+ BasicBlock::iterator It = EntryBlock.begin();
+ while (isa<AllocaInst>(*It) || isa<DbgInfoIntrinsic>(*It))
+ ++It;
+ EntryBlock.splitBasicBlock(It);
+
+ Funcs.push_back(make_unique<GCOVFunction>(SP, &out, FunctionIdent++,
+ Options.UseCfgChecksum,
+ Options.ExitBlockBeforeBody));
+ GCOVFunction &Func = *Funcs.back();
+
+ 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) {
+ // Debug intrinsic locations correspond to the location of the
+ // declaration, not necessarily any statements or expressions.
+ if (isa<DbgInfoIntrinsic>(I)) continue;
+
+ const DebugLoc &Loc = I->getDebugLoc();
+ if (!Loc)
+ continue;
+
+ // Artificial lines such as calls to the global constructors.
+ if (Loc.getLine() == 0) continue;
+
+ if (Line == Loc.getLine()) continue;
+ Line = Loc.getLine();
+ if (SP != getDISubprogram(Loc.getScope()))
+ continue;
+
+ GCOVLines &Lines = Block.getFile(SP->getFilename());
+ Lines.addLine(Loc.getLine());
+ }
+ }
+ EdgeDestinations += Func.getEdgeDestinations();
+ }
+
+ FileChecksums.push_back(hash_value(EdgeDestinations));
+ out.write("oncg", 4);
+ out.write(ReversedVersion, 4);
+ out.write(reinterpret_cast<char*>(&FileChecksums.back()), 4);
+
+ for (auto &Func : Funcs) {
+ Func->setCfgChecksum(FileChecksums.back());
+ 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) {
+ auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
+ SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
+ for (auto *SP : CU->getSubprograms()) {
+ Function *F = SP->getFunction();
+ if (!F) continue;
+ if (!functionHasLines(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, 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) {
+ if (Successors == 1) {
+ IRBuilder<> Builder(BB->getFirstInsertionPt());
+ Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
+ Edge);
+ Value *Count = Builder.CreateLoad(Counter);
+ Count = Builder.CreateAdd(Count, Builder.getInt64(1));
+ Builder.CreateStore(Count, Counter);
+ } else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
+ IRBuilder<> Builder(BI);
+ Value *Sel = Builder.CreateSelect(BI->getCondition(),
+ Builder.getInt64(Edge),
+ Builder.getInt64(Edge + 1));
+ SmallVector<Value *, 2> Idx;
+ Idx.push_back(Builder.getInt64(0));
+ Idx.push_back(Sel);
+ Value *Counter = Builder.CreateInBoundsGEP(Counters->getValueType(),
+ Counters, Idx);
+ Value *Count = Builder.CreateLoad(Counter);
+ Count = Builder.CreateAdd(Count, Builder.getInt64(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();
+
+ for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
+ IRBuilder<> Builder(ComplexEdgePreds[i + 1]->getFirstInsertionPt());
+ Builder.CreateStore(Builder.getInt32(i), EdgeState);
+ }
+
+ for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
+ // Call runtime to perform increment.
+ IRBuilder<> Builder(ComplexEdgeSuccs[i+1]->getFirstInsertionPt());
+ Value *CounterPtrArray =
+ Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
+ i * ComplexEdgePreds.size());
+
+ // Build code to increment the counter.
+ InsertIndCounterIncrCode = true;
+ Builder.CreateCall(getIncrementIndirectCounterFunc(),
+ {EdgeState, CounterPtrArray});
+ }
+ }
+ }
+
+ Function *WriteoutF = insertCounterWriteout(CountersBySP);
+ Function *FlushF = insertFlush(CountersBySP);
+
+ // Create a small bit of code that registers the "__llvm_gcov_writeout" to
+ // be executed at exit and the "__llvm_gcov_flush" function to be executed
+ // when "__gcov_flush" is called.
+ 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);
+ F->addFnAttr(Attribute::NoInline);
+ if (Options.NoRedZone)
+ F->addFnAttr(Attribute::NoRedZone);
+
+ BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", F);
+ IRBuilder<> Builder(BB);
+
+ FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
+ Type *Params[] = {
+ PointerType::get(FTy, 0),
+ PointerType::get(FTy, 0)
+ };
+ FTy = FunctionType::get(Builder.getVoidTy(), Params, false);
+
+ // Initialize the environment and register the local writeout and flush
+ // functions.
+ Constant *GCOVInit = M->getOrInsertFunction("llvm_gcov_init", FTy);
+ Builder.CreateCall(GCOVInit, {WriteoutF, FlushF});
+ Builder.CreateRetVoid();
+
+ appendToGlobalCtors(*M, F, 0);
+ }
+
+ 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*]].
+ size_t TableSize = Succs.size() * Preds.size();
+ Type *Int64PtrTy = Type::getInt64PtrTy(*Ctx);
+ ArrayType *EdgeTableTy = ArrayType::get(Int64PtrTy, TableSize);
+
+ std::unique_ptr<Constant * []> EdgeTable(new Constant *[TableSize]);
+ Constant *NullValue = Constant::getNullValue(Int64PtrTy);
+ for (size_t i = 0; i != TableSize; ++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;
+ }
+
+ GlobalVariable *EdgeTableGV =
+ new GlobalVariable(
+ *M, EdgeTableTy, true, GlobalValue::InternalLinkage,
+ ConstantArray::get(EdgeTableTy,
+ makeArrayRef(&EdgeTable[0],TableSize)),
+ "__llvm_gcda_edge_table");
+ EdgeTableGV->setUnnamedAddr(true);
+ return EdgeTableGV;
+}
+
+Constant *GCOVProfiler::getStartFileFunc() {
+ Type *Args[] = {
+ Type::getInt8PtrTy(*Ctx), // const char *orig_filename
+ Type::getInt8PtrTy(*Ctx), // const char version[4]
+ Type::getInt32Ty(*Ctx), // uint32_t checksum
+ };
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), Args, 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[] = {
+ Type::getInt32Ty(*Ctx), // uint32_t ident
+ Type::getInt8PtrTy(*Ctx), // const char *function_name
+ Type::getInt32Ty(*Ctx), // uint32_t func_checksum
+ Type::getInt8Ty(*Ctx), // uint8_t use_extra_checksum
+ Type::getInt32Ty(*Ctx), // uint32_t cfg_checksum
+ };
+ 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::getSummaryInfoFunc() {
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
+ return M->getOrInsertFunction("llvm_gcda_summary_info", FTy);
+}
+
+Constant *GCOVProfiler::getDeleteWriteoutFunctionListFunc() {
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
+ return M->getOrInsertFunction("llvm_delete_writeout_function_list", FTy);
+}
+
+Constant *GCOVProfiler::getDeleteFlushFunctionListFunc() {
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
+ return M->getOrInsertFunction("llvm_delete_flush_function_list", 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;
+}
+
+Function *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);
+ WriteoutF->addFnAttr(Attribute::NoInline);
+ if (Options.NoRedZone)
+ WriteoutF->addFnAttr(Attribute::NoRedZone);
+
+ BasicBlock *BB = BasicBlock::Create(*Ctx, "entry", WriteoutF);
+ IRBuilder<> Builder(BB);
+
+ Constant *StartFile = getStartFileFunc();
+ Constant *EmitFunction = getEmitFunctionFunc();
+ Constant *EmitArcs = getEmitArcsFunc();
+ Constant *SummaryInfo = getSummaryInfoFunc();
+ 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) {
+ auto *CU = cast<DICompileUnit>(CU_Nodes->getOperand(i));
+ std::string FilenameGcda = mangleName(CU, "gcda");
+ uint32_t CfgChecksum = FileChecksums.empty() ? 0 : FileChecksums[i];
+ Builder.CreateCall(StartFile,
+ {Builder.CreateGlobalStringPtr(FilenameGcda),
+ Builder.CreateGlobalStringPtr(ReversedVersion),
+ Builder.getInt32(CfgChecksum)});
+ for (unsigned j = 0, e = CountersBySP.size(); j != e; ++j) {
+ auto *SP = cast_or_null<DISubprogram>(CountersBySP[j].second);
+ uint32_t FuncChecksum = Funcs.empty() ? 0 : Funcs[j]->getFuncChecksum();
+ Builder.CreateCall(
+ EmitFunction,
+ {Builder.getInt32(j),
+ Options.FunctionNamesInData
+ ? Builder.CreateGlobalStringPtr(getFunctionName(SP))
+ : Constant::getNullValue(Builder.getInt8PtrTy()),
+ Builder.getInt32(FuncChecksum),
+ Builder.getInt8(Options.UseCfgChecksum),
+ Builder.getInt32(CfgChecksum)});
+
+ GlobalVariable *GV = CountersBySP[j].first;
+ unsigned Arcs =
+ cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
+ Builder.CreateCall(EmitArcs, {Builder.getInt32(Arcs),
+ Builder.CreateConstGEP2_64(GV, 0, 0)});
+ }
+ Builder.CreateCall(SummaryInfo, {});
+ Builder.CreateCall(EndFile, {});
+ }
+ }
+
+ Builder.CreateRetVoid();
+ return WriteoutF;
+}
+
+void GCOVProfiler::insertIndirectCounterIncrement() {
+ Function *Fn =
+ cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
+ Fn->setUnnamedAddr(true);
+ Fn->setLinkage(GlobalValue::InternalLinkage);
+ Fn->addFnAttr(Attribute::NoInline);
+ if (Options.NoRedZone)
+ Fn->addFnAttr(Attribute::NoRedZone);
+
+ // 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, Builder.getInt32(0xffffffff));
+ BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
+
+ Builder.SetInsertPoint(PredNotNegOne);
+
+ // uint64_t *counter = counters[pred];
+ // if (!counter) return;
+ Value *ZExtPred = Builder.CreateZExt(Pred, Builder.getInt64Ty());
+ Arg = std::next(Fn->arg_begin());
+ Arg->setName("counters");
+ Value *GEP = Builder.CreateGEP(Type::getInt64PtrTy(*Ctx), Arg, ZExtPred);
+ Value *Counter = Builder.CreateLoad(GEP, "counter");
+ Cond = Builder.CreateICmpEQ(Counter,
+ Constant::getNullValue(
+ Builder.getInt64Ty()->getPointerTo()));
+ Builder.CreateCondBr(Cond, Exit, CounterEnd);
+
+ // ++*counter;
+ Builder.SetInsertPoint(CounterEnd);
+ Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
+ Builder.getInt64(1));
+ Builder.CreateStore(Add, Counter);
+ Builder.CreateBr(Exit);
+
+ // Fill in the exit block.
+ Builder.SetInsertPoint(Exit);
+ Builder.CreateRetVoid();
+}
+
+Function *GCOVProfiler::
+insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
+ FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
+ Function *FlushF = M->getFunction("__llvm_gcov_flush");
+ if (!FlushF)
+ FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
+ "__llvm_gcov_flush", M);
+ else
+ FlushF->setLinkage(GlobalValue::InternalLinkage);
+ FlushF->setUnnamedAddr(true);
+ FlushF->addFnAttr(Attribute::NoInline);
+ if (Options.NoRedZone)
+ FlushF->addFnAttr(Attribute::NoRedZone);
+
+ 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 __llvm_gcov_flush was implicitly declared.
+ Builder.CreateRet(ConstantInt::get(RetTy, 0));
+ else
+ report_fatal_error("invalid return type for __llvm_gcov_flush");
+
+ return FlushF;
+}
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