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llvm-project/llvm/lib/IR/GCOV.cpp

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//===- GCOV.cpp - LLVM coverage tool --------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// GCOV implements the interface to read and write coverage files that use
// 'gcov' format.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Debug.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/GCOV.h"
#include "llvm/Support/MemoryObject.h"
#include "llvm/Support/system_error.h"
#include <algorithm>
using namespace llvm;
//===----------------------------------------------------------------------===//
// GCOVFile implementation.
/// ~GCOVFile - Delete GCOVFile and its content.
GCOVFile::~GCOVFile() {
DeleteContainerPointers(Functions);
}
/// readGCNO - Read GCNO buffer.
bool GCOVFile::readGCNO(GCOVBuffer &Buffer) {
if (!Buffer.readGCNOFormat()) return false;
if (!Buffer.readGCOVVersion(Version)) return false;
if (!Buffer.readInt(Checksum)) return false;
while (true) {
if (!Buffer.readFunctionTag()) break;
GCOVFunction *GFun = new GCOVFunction(*this);
if (!GFun->readGCNO(Buffer, Version))
return false;
Functions.push_back(GFun);
}
GCNOInitialized = true;
return true;
}
/// readGCDA - Read GCDA buffer. It is required that readGCDA() can only be
/// called after readGCNO().
bool GCOVFile::readGCDA(GCOVBuffer &Buffer) {
assert(GCNOInitialized && "readGCDA() can only be called after readGCNO()");
if (!Buffer.readGCDAFormat()) return false;
GCOV::GCOVVersion GCDAVersion;
if (!Buffer.readGCOVVersion(GCDAVersion)) return false;
if (Version != GCDAVersion) {
errs() << "GCOV versions do not match.\n";
return false;
}
uint32_t GCDAChecksum;
if (!Buffer.readInt(GCDAChecksum)) return false;
if (Checksum != GCDAChecksum) {
errs() << "File checksums do not match: " << Checksum << " != "
<< GCDAChecksum << ".\n";
return false;
}
for (size_t i = 0, e = Functions.size(); i < e; ++i) {
if (!Buffer.readFunctionTag()) {
errs() << "Unexpected number of functions.\n";
return false;
}
if (!Functions[i]->readGCDA(Buffer, Version))
return false;
}
if (Buffer.readObjectTag()) {
uint32_t Length;
uint32_t Dummy;
if (!Buffer.readInt(Length)) return false;
if (!Buffer.readInt(Dummy)) return false; // checksum
if (!Buffer.readInt(Dummy)) return false; // num
if (!Buffer.readInt(RunCount)) return false;
Buffer.advanceCursor(Length-3);
}
while (Buffer.readProgramTag()) {
uint32_t Length;
if (!Buffer.readInt(Length)) return false;
Buffer.advanceCursor(Length);
++ProgramCount;
}
return true;
}
/// dump - Dump GCOVFile content to dbgs() for debugging purposes.
void GCOVFile::dump() const {
for (SmallVectorImpl<GCOVFunction *>::const_iterator I = Functions.begin(),
E = Functions.end(); I != E; ++I)
(*I)->dump();
}
/// collectLineCounts - Collect line counts. This must be used after
/// reading .gcno and .gcda files.
void GCOVFile::collectLineCounts(FileInfo &FI) {
for (SmallVectorImpl<GCOVFunction *>::iterator I = Functions.begin(),
E = Functions.end(); I != E; ++I)
(*I)->collectLineCounts(FI);
FI.setRunCount(RunCount);
FI.setProgramCount(ProgramCount);
}
//===----------------------------------------------------------------------===//
// GCOVFunction implementation.
/// ~GCOVFunction - Delete GCOVFunction and its content.
GCOVFunction::~GCOVFunction() {
DeleteContainerPointers(Blocks);
DeleteContainerPointers(Edges);
}
/// readGCNO - Read a function from the GCNO buffer. Return false if an error
/// occurs.
bool GCOVFunction::readGCNO(GCOVBuffer &Buff, GCOV::GCOVVersion Version) {
uint32_t Dummy;
if (!Buff.readInt(Dummy)) return false; // Function header length
if (!Buff.readInt(Ident)) return false;
if (!Buff.readInt(Checksum)) return false;
if (Version != GCOV::V402) {
uint32_t CfgChecksum;
if (!Buff.readInt(CfgChecksum)) return false;
if (Parent.getChecksum() != CfgChecksum) {
errs() << "File checksums do not match: " << Parent.getChecksum()
<< " != " << CfgChecksum << " in (" << Name << ").\n";
return false;
}
}
if (!Buff.readString(Name)) return false;
if (!Buff.readString(Filename)) return false;
if (!Buff.readInt(LineNumber)) return false;
// read blocks.
if (!Buff.readBlockTag()) {
errs() << "Block tag not found.\n";
return false;
}
uint32_t BlockCount;
if (!Buff.readInt(BlockCount)) return false;
for (uint32_t i = 0, e = BlockCount; i != e; ++i) {
if (!Buff.readInt(Dummy)) return false; // Block flags;
Blocks.push_back(new GCOVBlock(*this, i));
}
// read edges.
while (Buff.readEdgeTag()) {
uint32_t EdgeCount;
if (!Buff.readInt(EdgeCount)) return false;
EdgeCount = (EdgeCount - 1) / 2;
uint32_t BlockNo;
if (!Buff.readInt(BlockNo)) return false;
if (BlockNo >= BlockCount) {
errs() << "Unexpected block number: " << BlockNo << " (in " << Name
<< ").\n";
return false;
}
for (uint32_t i = 0, e = EdgeCount; i != e; ++i) {
uint32_t Dst;
if (!Buff.readInt(Dst)) return false;
GCOVEdge *Edge = new GCOVEdge(Blocks[BlockNo], Blocks[Dst]);
Edges.push_back(Edge);
Blocks[BlockNo]->addDstEdge(Edge);
Blocks[Dst]->addSrcEdge(Edge);
if (!Buff.readInt(Dummy)) return false; // Edge flag
}
}
// read line table.
while (Buff.readLineTag()) {
uint32_t LineTableLength;
if (!Buff.readInt(LineTableLength)) return false;
uint32_t EndPos = Buff.getCursor() + LineTableLength*4;
uint32_t BlockNo;
if (!Buff.readInt(BlockNo)) return false;
if (BlockNo >= BlockCount) {
errs() << "Unexpected block number: " << BlockNo << " (in " << Name
<< ").\n";
return false;
}
GCOVBlock *Block = Blocks[BlockNo];
if (!Buff.readInt(Dummy)) return false; // flag
while (Buff.getCursor() != (EndPos - 4)) {
StringRef F;
if (!Buff.readString(F)) return false;
if (Filename != F) {
errs() << "Multiple sources for a single basic block: " << Filename
<< " != " << F << " (in " << Name << ").\n";
return false;
}
if (Buff.getCursor() == (EndPos - 4)) break;
while (true) {
uint32_t Line;
if (!Buff.readInt(Line)) return false;
if (!Line) break;
Block->addLine(Line);
}
}
if (!Buff.readInt(Dummy)) return false; // flag
}
return true;
}
/// readGCDA - Read a function from the GCDA buffer. Return false if an error
/// occurs.
bool GCOVFunction::readGCDA(GCOVBuffer &Buff, GCOV::GCOVVersion Version) {
uint32_t Dummy;
if (!Buff.readInt(Dummy)) return false; // Function header length
uint32_t GCDAIdent;
if (!Buff.readInt(GCDAIdent)) return false;
if (Ident != GCDAIdent) {
errs() << "Function identifiers do not match: " << Ident << " != "
<< GCDAIdent << " (in " << Name << ").\n";
return false;
}
uint32_t GCDAChecksum;
if (!Buff.readInt(GCDAChecksum)) return false;
if (Checksum != GCDAChecksum) {
errs() << "Function checksums do not match: " << Checksum << " != "
<< GCDAChecksum << " (in " << Name << ").\n";
return false;
}
uint32_t CfgChecksum;
if (Version != GCOV::V402) {
if (!Buff.readInt(CfgChecksum)) return false;
if (Parent.getChecksum() != CfgChecksum) {
errs() << "File checksums do not match: " << Parent.getChecksum()
<< " != " << CfgChecksum << " (in " << Name << ").\n";
return false;
}
}
StringRef GCDAName;
if (!Buff.readString(GCDAName)) return false;
if (Name != GCDAName) {
errs() << "Function names do not match: " << Name << " != " << GCDAName
<< ".\n";
return false;
}
if (!Buff.readArcTag()) {
errs() << "Arc tag not found (in " << Name << ").\n";
return false;
}
uint32_t Count;
if (!Buff.readInt(Count)) return false;
Count /= 2;
// This for loop adds the counts for each block. A second nested loop is
// required to combine the edge counts that are contained in the GCDA file.
for (uint32_t BlockNo = 0; Count > 0; ++BlockNo) {
// The last block is always reserved for exit block
if (BlockNo >= Blocks.size()-1) {
errs() << "Unexpected number of edges (in " << Name << ").\n";
return false;
}
GCOVBlock &Block = *Blocks[BlockNo];
for (size_t EdgeNo = 0, End = Block.getNumDstEdges(); EdgeNo < End;
++EdgeNo) {
if (Count == 0) {
errs() << "Unexpected number of edges (in " << Name << ").\n";
return false;
}
uint64_t ArcCount;
if (!Buff.readInt64(ArcCount)) return false;
Block.addCount(EdgeNo, ArcCount);
--Count;
}
Block.sortDstEdges();
}
return true;
}
/// getEntryCount - Get the number of times the function was called by
/// retrieving the entry block's count.
uint64_t GCOVFunction::getEntryCount() const {
return Blocks.front()->getCount();
}
/// getExitCount - Get the number of times the function returned by retrieving
/// the exit block's count.
uint64_t GCOVFunction::getExitCount() const {
return Blocks.back()->getCount();
}
/// dump - Dump GCOVFunction content to dbgs() for debugging purposes.
void GCOVFunction::dump() const {
dbgs() << "===== " << Name << " @ " << Filename << ":" << LineNumber << "\n";
for (SmallVectorImpl<GCOVBlock *>::const_iterator I = Blocks.begin(),
E = Blocks.end(); I != E; ++I)
(*I)->dump();
}
/// collectLineCounts - Collect line counts. This must be used after
/// reading .gcno and .gcda files.
void GCOVFunction::collectLineCounts(FileInfo &FI) {
for (SmallVectorImpl<GCOVBlock *>::iterator I = Blocks.begin(),
E = Blocks.end(); I != E; ++I)
(*I)->collectLineCounts(FI);
FI.addFunctionLine(Filename, LineNumber, this);
}
//===----------------------------------------------------------------------===//
// GCOVBlock implementation.
/// ~GCOVBlock - Delete GCOVBlock and its content.
GCOVBlock::~GCOVBlock() {
SrcEdges.clear();
DstEdges.clear();
Lines.clear();
}
/// addCount - Add to block counter while storing the edge count. If the
/// destination has no outgoing edges, also update that block's count too.
void GCOVBlock::addCount(size_t DstEdgeNo, uint64_t N) {
assert(DstEdgeNo < DstEdges.size()); // up to caller to ensure EdgeNo is valid
DstEdges[DstEdgeNo]->Count = N;
Counter += N;
if (!DstEdges[DstEdgeNo]->Dst->getNumDstEdges())
DstEdges[DstEdgeNo]->Dst->Counter += N;
}
/// sortDstEdges - Sort destination edges by block number, nop if already
/// sorted. This is required for printing branch info in the correct order.
void GCOVBlock::sortDstEdges() {
if (!DstEdgesAreSorted) {
SortDstEdgesFunctor SortEdges;
std::stable_sort(DstEdges.begin(), DstEdges.end(), SortEdges);
}
}
/// collectLineCounts - Collect line counts. This must be used after
/// reading .gcno and .gcda files.
void GCOVBlock::collectLineCounts(FileInfo &FI) {
for (SmallVectorImpl<uint32_t>::iterator I = Lines.begin(),
E = Lines.end(); I != E; ++I)
FI.addBlockLine(Parent.getFilename(), *I, this);
}
/// dump - Dump GCOVBlock content to dbgs() for debugging purposes.
void GCOVBlock::dump() const {
dbgs() << "Block : " << Number << " Counter : " << Counter << "\n";
if (!SrcEdges.empty()) {
dbgs() << "\tSource Edges : ";
for (EdgeIterator I = SrcEdges.begin(), E = SrcEdges.end(); I != E; ++I) {
const GCOVEdge *Edge = *I;
dbgs() << Edge->Src->Number << " (" << Edge->Count << "), ";
}
dbgs() << "\n";
}
if (!DstEdges.empty()) {
dbgs() << "\tDestination Edges : ";
for (EdgeIterator I = DstEdges.begin(), E = DstEdges.end(); I != E; ++I) {
const GCOVEdge *Edge = *I;
dbgs() << Edge->Dst->Number << " (" << Edge->Count << "), ";
}
dbgs() << "\n";
}
if (!Lines.empty()) {
dbgs() << "\tLines : ";
for (SmallVectorImpl<uint32_t>::const_iterator I = Lines.begin(),
E = Lines.end(); I != E; ++I)
dbgs() << (*I) << ",";
dbgs() << "\n";
}
}
//===----------------------------------------------------------------------===//
// FileInfo implementation.
// Safe integer division, returns 0 if numerator is 0.
static uint32_t safeDiv(uint64_t Numerator, uint64_t Divisor) {
if (!Numerator)
return 0;
return Numerator/Divisor;
}
// This custom division function mimics gcov's branch ouputs:
// - Round to closest whole number
// - Only output 0% or 100% if it's exactly that value
static uint32_t branchDiv(uint64_t Numerator, uint64_t Divisor) {
if (!Numerator)
return 0;
if (Numerator == Divisor)
return 100;
uint8_t Res = (Numerator*100+Divisor/2) / Divisor;
if (Res == 0)
return 1;
if (Res == 100)
return 99;
return Res;
}
struct formatBranchInfo {
formatBranchInfo(const GCOVOptions &Options, uint64_t Count,
uint64_t Total) :
Options(Options), Count(Count), Total(Total) {}
void print(raw_ostream &OS) const {
if (!Total)
OS << "never executed";
else if (Options.BranchCount)
OS << "taken " << Count;
else
OS << "taken " << branchDiv(Count, Total) << "%";
}
const GCOVOptions &Options;
uint64_t Count;
uint64_t Total;
};
static raw_ostream &operator<<(raw_ostream &OS, const formatBranchInfo &FBI) {
FBI.print(OS);
return OS;
}
/// print - Print source files with collected line count information.
void FileInfo::print(StringRef GCNOFile, StringRef GCDAFile) {
for (StringMap<LineData>::const_iterator I = LineInfo.begin(),
E = LineInfo.end(); I != E; ++I) {
StringRef Filename = I->first();
OwningPtr<MemoryBuffer> Buff;
if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
errs() << Filename << ": " << ec.message() << "\n";
return;
}
StringRef AllLines = Buff->getBuffer();
std::string CovFilename = Filename.str() + ".gcov";
std::string ErrorInfo;
raw_fd_ostream OS(CovFilename.c_str(), ErrorInfo);
if (!ErrorInfo.empty())
errs() << ErrorInfo << "\n";
OS << " -: 0:Source:" << Filename << "\n";
OS << " -: 0:Graph:" << GCNOFile << "\n";
OS << " -: 0:Data:" << GCDAFile << "\n";
OS << " -: 0:Runs:" << RunCount << "\n";
OS << " -: 0:Programs:" << ProgramCount << "\n";
const LineData &Line = I->second;
GCOVCoverage FileCoverage(Filename);
for (uint32_t LineIndex = 0; !AllLines.empty(); ++LineIndex) {
if (Options.BranchInfo) {
FunctionLines::const_iterator FuncsIt = Line.Functions.find(LineIndex);
if (FuncsIt != Line.Functions.end())
printFunctionSummary(OS, FuncsIt->second);
}
BlockLines::const_iterator BlocksIt = Line.Blocks.find(LineIndex);
if (BlocksIt == Line.Blocks.end()) {
// No basic blocks are on this line. Not an executable line of code.
OS << " -:";
std::pair<StringRef, StringRef> P = AllLines.split('\n');
OS << format("%5u:", LineIndex+1) << P.first << "\n";
AllLines = P.second;
} else {
const BlockVector &Blocks = BlocksIt->second;
// Add up the block counts to form line counts.
DenseMap<const GCOVFunction *, bool> LineExecs;
uint64_t LineCount = 0;
for (BlockVector::const_iterator I = Blocks.begin(), E = Blocks.end();
I != E; ++I) {
const GCOVBlock *Block = *I;
if (Options.AllBlocks) {
// Only take the highest block count for that line.
uint64_t BlockCount = Block->getCount();
LineCount = LineCount > BlockCount ? LineCount : BlockCount;
} else {
// Sum up all of the block counts.
LineCount += Block->getCount();
}
if (Options.FuncCoverage) {
// This is a slightly convoluted way to most accurately gather line
// statistics for functions. Basically what is happening is that we
// don't want to count a single line with multiple blocks more than
// once. However, we also don't simply want to give the total line
// count to every function that starts on the line. Thus, what is
// happening here are two things:
// 1) Ensure that the number of logical lines is only incremented
// once per function.
// 2) If there are multiple blocks on the same line, ensure that the
// number of lines executed is incremented as long as at least
// one of the blocks are executed.
const GCOVFunction *Function = &Block->getParent();
if (FuncCoverages.find(Function) == FuncCoverages.end()) {
std::pair<const GCOVFunction *, GCOVCoverage>
KeyValue(Function, GCOVCoverage(Function->getName()));
FuncCoverages.insert(KeyValue);
}
GCOVCoverage &FuncCoverage = FuncCoverages.find(Function)->second;
if (LineExecs.find(Function) == LineExecs.end()) {
if (Block->getCount()) {
++FuncCoverage.LinesExec;
LineExecs[Function] = true;
} else {
LineExecs[Function] = false;
}
++FuncCoverage.LogicalLines;
} else if (!LineExecs[Function] && Block->getCount()) {
++FuncCoverage.LinesExec;
LineExecs[Function] = true;
}
}
}
if (LineCount == 0)
OS << " #####:";
else {
OS << format("%9" PRIu64 ":", LineCount);
++FileCoverage.LinesExec;
}
++FileCoverage.LogicalLines;
std::pair<StringRef, StringRef> P = AllLines.split('\n');
OS << format("%5u:", LineIndex+1) << P.first << "\n";
AllLines = P.second;
uint32_t BlockNo = 0;
uint32_t EdgeNo = 0;
for (BlockVector::const_iterator I = Blocks.begin(), E = Blocks.end();
I != E; ++I) {
const GCOVBlock *Block = *I;
// Only print block and branch information at the end of the block.
if (Block->getLastLine() != LineIndex+1)
continue;
if (Options.AllBlocks)
printBlockInfo(OS, *Block, LineIndex, BlockNo);
if (Options.BranchInfo) {
size_t NumEdges = Block->getNumDstEdges();
if (NumEdges > 1)
printBranchInfo(OS, *Block, FileCoverage, EdgeNo);
else if (Options.UncondBranch && NumEdges == 1)
printUncondBranchInfo(OS, EdgeNo, (*Block->dst_begin())->Count);
}
}
}
}
FileCoverages.push_back(FileCoverage);
}
// FIXME: There is no way to detect calls given current instrumentation.
if (Options.FuncCoverage)
printFuncCoverage();
printFileCoverage();
}
/// printFunctionSummary - Print function and block summary.
void FileInfo::printFunctionSummary(raw_fd_ostream &OS,
const FunctionVector &Funcs) const {
for (FunctionVector::const_iterator I = Funcs.begin(), E = Funcs.end();
I != E; ++I) {
const GCOVFunction *Func = *I;
uint64_t EntryCount = Func->getEntryCount();
uint32_t BlocksExec = 0;
for (GCOVFunction::BlockIterator I = Func->block_begin(),
E = Func->block_end(); I != E; ++I) {
const GCOVBlock *Block = *I;
if (Block->getNumDstEdges() && Block->getCount())
++BlocksExec;
}
OS << "function " << Func->getName() << " called " << EntryCount
<< " returned " << safeDiv(Func->getExitCount()*100, EntryCount)
<< "% blocks executed "
<< safeDiv(BlocksExec*100, Func->getNumBlocks()-1) << "%\n";
}
}
/// printBlockInfo - Output counts for each block.
void FileInfo::printBlockInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
uint32_t LineIndex, uint32_t &BlockNo) const {
if (Block.getCount() == 0)
OS << " $$$$$:";
else
OS << format("%9" PRIu64 ":", Block.getCount());
OS << format("%5u-block %2u\n", LineIndex+1, BlockNo++);
}
/// printBranchInfo - Print conditional branch probabilities.
void FileInfo::printBranchInfo(raw_fd_ostream &OS, const GCOVBlock &Block,
GCOVCoverage &Coverage, uint32_t &EdgeNo) {
SmallVector<uint64_t, 16> BranchCounts;
uint64_t TotalCounts = 0;
for (GCOVBlock::EdgeIterator I = Block.dst_begin(), E = Block.dst_end();
I != E; ++I) {
const GCOVEdge *Edge = *I;
BranchCounts.push_back(Edge->Count);
TotalCounts += Edge->Count;
if (Block.getCount()) ++Coverage.BranchesExec;
if (Edge->Count) ++Coverage.BranchesTaken;
++Coverage.Branches;
if (Options.FuncCoverage) {
const GCOVFunction *Function = &Block.getParent();
GCOVCoverage &FuncCoverage = FuncCoverages.find(Function)->second;
if (Block.getCount()) ++FuncCoverage.BranchesExec;
if (Edge->Count) ++FuncCoverage.BranchesTaken;
++FuncCoverage.Branches;
}
}
for (SmallVectorImpl<uint64_t>::const_iterator I = BranchCounts.begin(),
E = BranchCounts.end(); I != E; ++I) {
OS << format("branch %2u ", EdgeNo++)
<< formatBranchInfo(Options, *I, TotalCounts) << "\n";
}
}
/// printUncondBranchInfo - Print unconditional branch probabilities.
void FileInfo::printUncondBranchInfo(raw_fd_ostream &OS, uint32_t &EdgeNo,
uint64_t Count) const {
OS << format("unconditional %2u ", EdgeNo++)
<< formatBranchInfo(Options, Count, Count) << "\n";
}
// printCoverage - Print generic coverage info used by both printFuncCoverage
// and printFileCoverage.
void FileInfo::printCoverage(const GCOVCoverage &Coverage) const {
outs() << format("Lines executed:%.2f%% of %u\n",
double(Coverage.LinesExec)*100/Coverage.LogicalLines,
Coverage.LogicalLines);
if (Options.BranchInfo) {
if (Coverage.Branches) {
outs() << format("Branches executed:%.2f%% of %u\n",
double(Coverage.BranchesExec)*100/Coverage.Branches,
Coverage.Branches);
outs() << format("Taken at least once:%.2f%% of %u\n",
double(Coverage.BranchesTaken)*100/Coverage.Branches,
Coverage.Branches);
} else {
outs() << "No branches\n";
}
outs() << "No calls\n"; // to be consistent with gcov
}
}
// printFuncCoverage - Print per-function coverage info.
void FileInfo::printFuncCoverage() const {
for (MapVector<const GCOVFunction *, GCOVCoverage>::const_iterator I =
FuncCoverages.begin(), E = FuncCoverages.end(); I != E; ++I) {
const GCOVCoverage &Coverage = I->second;
outs() << "Function '" << Coverage.Name << "'\n";
printCoverage(Coverage);
outs() << "\n";
}
}
// printFileCoverage - Print per-file coverage info.
void FileInfo::printFileCoverage() const {
for (SmallVectorImpl<GCOVCoverage>::const_iterator I =
FileCoverages.begin(), E = FileCoverages.end(); I != E; ++I) {
const GCOVCoverage &Coverage = *I;
outs() << "File '" << Coverage.Name << "'\n";
printCoverage(Coverage);
outs() << Coverage.Name << ":creating '" << Coverage.Name
<< ".gcov'\n\n";
}
}
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