llvm-6502/lib/Transforms/Instrumentation/GCOVProfiling.cpp
Chandler Carruth 0b8c9a80f2 Move all of the header files which are involved in modelling the LLVM IR
into their new header subdirectory: include/llvm/IR. This matches the
directory structure of lib, and begins to correct a long standing point
of file layout clutter in LLVM.

There are still more header files to move here, but I wanted to handle
them in separate commits to make tracking what files make sense at each
layer easier.

The only really questionable files here are the target intrinsic
tablegen files. But that's a battle I'd rather not fight today.

I've updated both CMake and Makefile build systems (I think, and my
tests think, but I may have missed something).

I've also re-sorted the includes throughout the project. I'll be
committing updates to Clang, DragonEgg, and Polly momentarily.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171366 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-02 11:36:10 +00:00

803 lines
28 KiB
C++

//===- 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.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "insert-gcov-profiling"
#include "llvm/Transforms/Instrumentation.h"
#include "ProfilingUtils.h"
#include "llvm/ADT/DenseMap.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/DebugInfo.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/DebugLoc.h"
#include "llvm/Support/InstIterator.h"
#include "llvm/Support/PathV2.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/ModuleUtils.h"
#include <string>
#include <utility>
using namespace llvm;
namespace {
class GCOVProfiler : public ModulePass {
public:
static char ID;
GCOVProfiler()
: ModulePass(ID), EmitNotes(true), EmitData(true), Use402Format(false),
UseExtraChecksum(false), NoRedZone(false) {
initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
}
GCOVProfiler(bool EmitNotes, bool EmitData, bool use402Format,
bool useExtraChecksum, bool NoRedZone_)
: ModulePass(ID), EmitNotes(EmitNotes), EmitData(EmitData),
Use402Format(use402Format), UseExtraChecksum(useExtraChecksum),
NoRedZone(NoRedZone_) {
assert((EmitNotes || EmitData) && "GCOVProfiler asked to do nothing?");
initializeGCOVProfilerPass(*PassRegistry::getPassRegistry());
}
virtual const char *getPassName() const {
return "GCOV Profiler";
}
private:
bool runOnModule(Module &M);
// Create the GCNO files for the Module based on DebugInfo.
void emitGCNO();
// 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 *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.
void insertCounterWriteout(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
void insertIndirectCounterIncrement();
void insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> >);
std::string mangleName(DICompileUnit CU, const char *NewStem);
bool EmitNotes;
bool EmitData;
bool Use402Format;
bool UseExtraChecksum;
bool NoRedZone;
Module *M;
LLVMContext *Ctx;
};
}
char GCOVProfiler::ID = 0;
INITIALIZE_PASS(GCOVProfiler, "insert-gcov-profiling",
"Insert instrumentation for GCOV profiling", false, false)
ModulePass *llvm::createGCOVProfilerPass(bool EmitNotes, bool EmitData,
bool Use402Format,
bool UseExtraChecksum,
bool NoRedZone) {
return new GCOVProfiler(EmitNotes, EmitData, Use402Format, UseExtraChecksum,
NoRedZone);
}
namespace {
class GCOVRecord {
protected:
static const char *LinesTag;
static const char *FunctionTag;
static const char *BlockTag;
static const char *EdgeTag;
GCOVRecord() {}
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
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 *GCOVRecord::LinesTag = "\0\0\x45\x01";
const char *GCOVRecord::FunctionTag = "\0\0\0\1";
const char *GCOVRecord::BlockTag = "\0\0\x41\x01";
const char *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) {
Lines.push_back(Line);
}
uint32_t length() {
// 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;
for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
E = LinesByFile.end(); I != E; ++I) {
Len += I->second->length();
}
writeBytes(LinesTag, 4);
write(Len);
write(Number);
for (StringMap<GCOVLines *>::iterator I = LinesByFile.begin(),
E = LinesByFile.end(); I != E; ++I)
I->second->writeOut();
write(0);
write(0);
}
~GCOVBlock() {
DeleteContainerSeconds(LinesByFile);
}
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(DISubprogram SP, raw_ostream *os,
bool Use402Format, bool UseExtraChecksum) {
this->os = os;
Function *F = SP.getFunction();
DEBUG(dbgs() << "Function: " << F->getName() << "\n");
uint32_t i = 0;
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
Blocks[BB] = new GCOVBlock(i++, os);
}
ReturnBlock = new GCOVBlock(i++, os);
writeBytes(FunctionTag, 4);
uint32_t BlockLen = 1 + 1 + 1 + lengthOfGCOVString(SP.getName()) +
1 + lengthOfGCOVString(SP.getFilename()) + 1;
if (UseExtraChecksum)
++BlockLen;
write(BlockLen);
uint32_t Ident = reinterpret_cast<intptr_t>((MDNode*)SP);
write(Ident);
write(0); // lineno checksum
if (UseExtraChecksum)
write(0); // cfg checksum
writeGCOVString(SP.getName());
writeGCOVString(SP.getFilename());
write(SP.getLineNumber());
}
~GCOVFunction() {
DeleteContainerSeconds(Blocks);
delete ReturnBlock;
}
GCOVBlock &getBlock(BasicBlock *BB) {
return *Blocks[BB];
}
GCOVBlock &getReturnBlock() {
return *ReturnBlock;
}
void writeOut() {
// 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.
for (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(),
E = Blocks.end(); I != E; ++I) {
GCOVBlock &Block = *I->second;
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 (DenseMap<BasicBlock *, GCOVBlock *>::iterator I = Blocks.begin(),
E = Blocks.end(); I != E; ++I) {
I->second->writeOut();
}
}
private:
DenseMap<BasicBlock *, GCOVBlock *> Blocks;
GCOVBlock *ReturnBlock;
};
}
std::string GCOVProfiler::mangleName(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);
return sys::path::filename(Filename.str());
}
bool GCOVProfiler::runOnModule(Module &M) {
this->M = &M;
Ctx = &M.getContext();
if (EmitNotes) emitGCNO();
if (EmitData) return emitProfileArcs();
return false;
}
void GCOVProfiler::emitGCNO() {
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.
DICompileUnit CU(CU_Nodes->getOperand(i));
std::string ErrorInfo;
raw_fd_ostream out(mangleName(CU, "gcno").c_str(), ErrorInfo,
raw_fd_ostream::F_Binary);
if (!Use402Format)
out.write("oncg*404MVLL", 12);
else
out.write("oncg*204MVLL", 12);
DIArray SPs = CU.getSubprograms();
for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
DISubprogram SP(SPs.getElement(i));
if (!SP.Verify()) continue;
Function *F = SP.getFunction();
if (!F) continue;
GCOVFunction Func(SP, &out, Use402Format, UseExtraChecksum);
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) {
const DebugLoc &Loc = I->getDebugLoc();
if (Loc.isUnknown()) continue;
if (Line == Loc.getLine()) continue;
Line = Loc.getLine();
if (SP != getDISubprogram(Loc.getScope(*Ctx))) continue;
GCOVLines &Lines = Block.getFile(SP.getFilename());
Lines.addLine(Loc.getLine());
}
}
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) {
DICompileUnit CU(CU_Nodes->getOperand(i));
DIArray SPs = CU.getSubprograms();
SmallVector<std::pair<GlobalVariable *, MDNode *>, 8> CountersBySP;
for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i) {
DISubprogram SP(SPs.getElement(i));
if (!SP.Verify()) continue;
Function *F = SP.getFunction();
if (!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, (MDNode*)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) {
IRBuilder<> Builder(TI);
if (Successors == 1) {
Value *Counter = Builder.CreateConstInBoundsGEP2_64(Counters, 0,
Edge);
Value *Count = Builder.CreateLoad(Counter);
Count = Builder.CreateAdd(Count,
ConstantInt::get(Type::getInt64Ty(*Ctx),1));
Builder.CreateStore(Count, Counter);
} else if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
Value *Sel = Builder.CreateSelect(
BI->getCondition(),
ConstantInt::get(Type::getInt64Ty(*Ctx), Edge),
ConstantInt::get(Type::getInt64Ty(*Ctx), Edge + 1));
SmallVector<Value *, 2> Idx;
Idx.push_back(Constant::getNullValue(Type::getInt64Ty(*Ctx)));
Idx.push_back(Sel);
Value *Counter = Builder.CreateInBoundsGEP(Counters, Idx);
Value *Count = Builder.CreateLoad(Counter);
Count = Builder.CreateAdd(Count,
ConstantInt::get(Type::getInt64Ty(*Ctx),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();
Type *Int32Ty = Type::getInt32Ty(*Ctx);
for (int i = 0, e = ComplexEdgePreds.size(); i != e; ++i) {
IRBuilder<> Builder(ComplexEdgePreds[i+1]->getTerminator());
Builder.CreateStore(ConstantInt::get(Int32Ty, i), EdgeState);
}
for (int i = 0, e = ComplexEdgeSuccs.size(); i != e; ++i) {
// call runtime to perform increment
BasicBlock::iterator InsertPt =
ComplexEdgeSuccs[i+1]->getFirstInsertionPt();
IRBuilder<> Builder(InsertPt);
Value *CounterPtrArray =
Builder.CreateConstInBoundsGEP2_64(EdgeTable, 0,
i * ComplexEdgePreds.size());
// Build code to increment the counter.
InsertIndCounterIncrCode = true;
Builder.CreateCall2(getIncrementIndirectCounterFunc(),
EdgeState, CounterPtrArray);
}
}
}
insertCounterWriteout(CountersBySP);
insertFlush(CountersBySP);
}
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);
OwningArrayPtr<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;
}
ArrayRef<Constant*> V(&EdgeTable[0], TableSize);
GlobalVariable *EdgeTableGV =
new GlobalVariable(
*M, EdgeTableTy, true, GlobalValue::InternalLinkage,
ConstantArray::get(EdgeTableTy, V),
"__llvm_gcda_edge_table");
EdgeTableGV->setUnnamedAddr(true);
return EdgeTableGV;
}
Constant *GCOVProfiler::getStartFileFunc() {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx),
Type::getInt8PtrTy(*Ctx), 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[2] = {
Type::getInt32Ty(*Ctx), // uint32_t ident
Type::getInt8PtrTy(*Ctx), // const char *function_name
};
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::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;
}
void 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 (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 *EndFile = getEndFileFunc();
NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
if (CU_Nodes) {
for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
DICompileUnit CU(CU_Nodes->getOperand(i));
std::string FilenameGcda = mangleName(CU, "gcda");
Builder.CreateCall(StartFile,
Builder.CreateGlobalStringPtr(FilenameGcda));
for (ArrayRef<std::pair<GlobalVariable *, MDNode *> >::iterator
I = CountersBySP.begin(), E = CountersBySP.end();
I != E; ++I) {
DISubprogram SP(I->second);
intptr_t ident = reinterpret_cast<intptr_t>(I->second);
Builder.CreateCall2(EmitFunction,
ConstantInt::get(Type::getInt32Ty(*Ctx), ident),
Builder.CreateGlobalStringPtr(SP.getName()));
GlobalVariable *GV = I->first;
unsigned Arcs =
cast<ArrayType>(GV->getType()->getElementType())->getNumElements();
Builder.CreateCall2(EmitArcs,
ConstantInt::get(Type::getInt32Ty(*Ctx), Arcs),
Builder.CreateConstGEP2_64(GV, 0, 0));
}
Builder.CreateCall(EndFile);
}
}
Builder.CreateRetVoid();
// Create a small bit of code that registers the "__llvm_gcov_writeout"
// function to be executed at exit.
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 (NoRedZone)
F->addFnAttr(Attribute::NoRedZone);
BB = BasicBlock::Create(*Ctx, "entry", F);
Builder.SetInsertPoint(BB);
FTy = FunctionType::get(Type::getInt32Ty(*Ctx),
PointerType::get(FTy, 0), false);
Constant *AtExitFn = M->getOrInsertFunction("atexit", FTy);
Builder.CreateCall(AtExitFn, WriteoutF);
Builder.CreateRetVoid();
appendToGlobalCtors(*M, F, 0);
}
void GCOVProfiler::insertIndirectCounterIncrement() {
Function *Fn =
cast<Function>(GCOVProfiler::getIncrementIndirectCounterFunc());
Fn->setUnnamedAddr(true);
Fn->setLinkage(GlobalValue::InternalLinkage);
Fn->addFnAttr(Attribute::NoInline);
if (NoRedZone)
Fn->addFnAttr(Attribute::NoRedZone);
Type *Int32Ty = Type::getInt32Ty(*Ctx);
Type *Int64Ty = Type::getInt64Ty(*Ctx);
Constant *NegOne = ConstantInt::get(Int32Ty, 0xffffffff);
// 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, NegOne);
BranchInst::Create(Exit, PredNotNegOne, Cond, BB);
Builder.SetInsertPoint(PredNotNegOne);
// uint64_t *counter = counters[pred];
// if (!counter) return;
Value *ZExtPred = Builder.CreateZExt(Pred, Int64Ty);
Arg = llvm::next(Fn->arg_begin());
Arg->setName("counters");
Value *GEP = Builder.CreateGEP(Arg, ZExtPred);
Value *Counter = Builder.CreateLoad(GEP, "counter");
Cond = Builder.CreateICmpEQ(Counter,
Constant::getNullValue(Int64Ty->getPointerTo()));
Builder.CreateCondBr(Cond, Exit, CounterEnd);
// ++*counter;
Builder.SetInsertPoint(CounterEnd);
Value *Add = Builder.CreateAdd(Builder.CreateLoad(Counter),
ConstantInt::get(Int64Ty, 1));
Builder.CreateStore(Add, Counter);
Builder.CreateBr(Exit);
// Fill in the exit block.
Builder.SetInsertPoint(Exit);
Builder.CreateRetVoid();
}
void GCOVProfiler::
insertFlush(ArrayRef<std::pair<GlobalVariable*, MDNode*> > CountersBySP) {
FunctionType *FTy = FunctionType::get(Type::getVoidTy(*Ctx), false);
Function *FlushF = M->getFunction("__gcov_flush");
if (!FlushF)
FlushF = Function::Create(FTy, GlobalValue::InternalLinkage,
"__gcov_flush", M);
else
FlushF->setLinkage(GlobalValue::InternalLinkage);
FlushF->setUnnamedAddr(true);
FlushF->addFnAttr(Attribute::NoInline);
if (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 __gcov_flush was implicitly declared.
Builder.CreateRet(ConstantInt::get(RetTy, 0));
else
report_fatal_error("invalid return type for __gcov_flush");
}