llvm/tools/llvm-prof/llvm-prof.cpp
2010-08-06 18:33:48 +00:00

289 lines
9.6 KiB
C++

//===- llvm-prof.cpp - Read in and process llvmprof.out data files --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tools is meant for use with the various LLVM profiling instrumentation
// passes. It reads in the data file produced by executing an instrumented
// program, and outputs a nice report.
//
//===----------------------------------------------------------------------===//
#include "llvm/InstrTypes.h"
#include "llvm/LLVMContext.h"
#include "llvm/Module.h"
#include "llvm/PassManager.h"
#include "llvm/Assembly/AsmAnnotationWriter.h"
#include "llvm/Analysis/ProfileInfo.h"
#include "llvm/Analysis/ProfileInfoLoader.h"
#include "llvm/Analysis/Passes.h"
#include "llvm/Bitcode/ReaderWriter.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Format.h"
#include "llvm/System/Signals.h"
#include <algorithm>
#include <iomanip>
#include <map>
#include <set>
using namespace llvm;
namespace {
cl::opt<std::string>
BitcodeFile(cl::Positional, cl::desc("<program bitcode file>"),
cl::Required);
cl::opt<std::string>
ProfileDataFile(cl::Positional, cl::desc("<llvmprof.out file>"),
cl::Optional, cl::init("llvmprof.out"));
cl::opt<bool>
PrintAnnotatedLLVM("annotated-llvm",
cl::desc("Print LLVM code with frequency annotations"));
cl::alias PrintAnnotated2("A", cl::desc("Alias for --annotated-llvm"),
cl::aliasopt(PrintAnnotatedLLVM));
cl::opt<bool>
PrintAllCode("print-all-code",
cl::desc("Print annotated code for the entire program"));
}
// PairSecondSort - A sorting predicate to sort by the second element of a pair.
template<class T>
struct PairSecondSortReverse
: public std::binary_function<std::pair<T, double>,
std::pair<T, double>, bool> {
bool operator()(const std::pair<T, double> &LHS,
const std::pair<T, double> &RHS) const {
return LHS.second > RHS.second;
}
};
static double ignoreMissing(double w) {
if (w == ProfileInfo::MissingValue) return 0;
return w;
}
namespace {
class ProfileAnnotator : public AssemblyAnnotationWriter {
ProfileInfo &PI;
public:
ProfileAnnotator(ProfileInfo& pi) : PI(pi) {}
virtual void emitFunctionAnnot(const Function *F, raw_ostream &OS) {
double w = PI.getExecutionCount(F);
if (w != ProfileInfo::MissingValue) {
OS << ";;; %" << F->getName() << " called "<<(unsigned)w
<<" times.\n;;;\n";
}
}
virtual void emitBasicBlockStartAnnot(const BasicBlock *BB,
raw_ostream &OS) {
double w = PI.getExecutionCount(BB);
if (w != ProfileInfo::MissingValue) {
if (w != 0) {
OS << "\t;;; Basic block executed " << (unsigned)w << " times.\n";
} else {
OS << "\t;;; Never executed!\n";
}
}
}
virtual void emitBasicBlockEndAnnot(const BasicBlock *BB, raw_ostream &OS) {
// Figure out how many times each successor executed.
std::vector<std::pair<ProfileInfo::Edge, double> > SuccCounts;
const TerminatorInst *TI = BB->getTerminator();
for (unsigned s = 0, e = TI->getNumSuccessors(); s != e; ++s) {
BasicBlock* Succ = TI->getSuccessor(s);
double w = ignoreMissing(PI.getEdgeWeight(std::make_pair(BB, Succ)));
if (w != 0)
SuccCounts.push_back(std::make_pair(std::make_pair(BB, Succ), w));
}
if (!SuccCounts.empty()) {
OS << "\t;;; Out-edge counts:";
for (unsigned i = 0, e = SuccCounts.size(); i != e; ++i)
OS << " [" << (SuccCounts[i]).second << " -> "
<< (SuccCounts[i]).first.second->getName() << "]";
OS << "\n";
}
}
};
}
namespace {
/// ProfileInfoPrinterPass - Helper pass to dump the profile information for
/// a module.
//
// FIXME: This should move elsewhere.
class ProfileInfoPrinterPass : public ModulePass {
ProfileInfoLoader &PIL;
public:
static char ID; // Class identification, replacement for typeinfo.
explicit ProfileInfoPrinterPass(ProfileInfoLoader &_PIL)
: ModulePass(ID), PIL(_PIL) {}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequired<ProfileInfo>();
}
bool runOnModule(Module &M);
};
}
char ProfileInfoPrinterPass::ID = 0;
bool ProfileInfoPrinterPass::runOnModule(Module &M) {
ProfileInfo &PI = getAnalysis<ProfileInfo>();
std::map<const Function *, unsigned> FuncFreqs;
std::map<const BasicBlock*, unsigned> BlockFreqs;
std::map<ProfileInfo::Edge, unsigned> EdgeFreqs;
// Output a report. Eventually, there will be multiple reports selectable on
// the command line, for now, just keep things simple.
// Emit the most frequent function table...
std::vector<std::pair<Function*, double> > FunctionCounts;
std::vector<std::pair<BasicBlock*, double> > Counts;
for (Module::iterator FI = M.begin(), FE = M.end(); FI != FE; ++FI) {
if (FI->isDeclaration()) continue;
double w = ignoreMissing(PI.getExecutionCount(FI));
FunctionCounts.push_back(std::make_pair(FI, w));
for (Function::iterator BB = FI->begin(), BBE = FI->end();
BB != BBE; ++BB) {
double w = ignoreMissing(PI.getExecutionCount(BB));
Counts.push_back(std::make_pair(BB, w));
}
}
// Sort by the frequency, backwards.
sort(FunctionCounts.begin(), FunctionCounts.end(),
PairSecondSortReverse<Function*>());
double TotalExecutions = 0;
for (unsigned i = 0, e = FunctionCounts.size(); i != e; ++i)
TotalExecutions += FunctionCounts[i].second;
outs() << "===" << std::string(73, '-') << "===\n"
<< "LLVM profiling output for execution";
if (PIL.getNumExecutions() != 1) outs() << "s";
outs() << ":\n";
for (unsigned i = 0, e = PIL.getNumExecutions(); i != e; ++i) {
outs() << " ";
if (e != 1) outs() << i+1 << ". ";
outs() << PIL.getExecution(i) << "\n";
}
outs() << "\n===" << std::string(73, '-') << "===\n";
outs() << "Function execution frequencies:\n\n";
// Print out the function frequencies...
outs() << " ## Frequency\n";
for (unsigned i = 0, e = FunctionCounts.size(); i != e; ++i) {
if (FunctionCounts[i].second == 0) {
outs() << "\n NOTE: " << e-i << " function"
<< (e-i-1 ? "s were" : " was") << " never executed!\n";
break;
}
outs() << format("%3d", i+1) << ". "
<< format("%5.2g", FunctionCounts[i].second) << "/"
<< format("%g", TotalExecutions) << " "
<< FunctionCounts[i].first->getNameStr() << "\n";
}
std::set<Function*> FunctionsToPrint;
TotalExecutions = 0;
for (unsigned i = 0, e = Counts.size(); i != e; ++i)
TotalExecutions += Counts[i].second;
// Sort by the frequency, backwards.
sort(Counts.begin(), Counts.end(),
PairSecondSortReverse<BasicBlock*>());
outs() << "\n===" << std::string(73, '-') << "===\n";
outs() << "Top 20 most frequently executed basic blocks:\n\n";
// Print out the function frequencies...
outs() <<" ## %% \tFrequency\n";
unsigned BlocksToPrint = Counts.size();
if (BlocksToPrint > 20) BlocksToPrint = 20;
for (unsigned i = 0; i != BlocksToPrint; ++i) {
if (Counts[i].second == 0) break;
Function *F = Counts[i].first->getParent();
outs() << format("%3d", i+1) << ". "
<< format("%5g", Counts[i].second/(double)TotalExecutions*100) << "% "
<< format("%5.0f", Counts[i].second) << "/"
<< format("%g", TotalExecutions) << "\t"
<< F->getNameStr() << "() - "
<< Counts[i].first->getNameStr() << "\n";
FunctionsToPrint.insert(F);
}
if (PrintAnnotatedLLVM || PrintAllCode) {
outs() << "\n===" << std::string(73, '-') << "===\n";
outs() << "Annotated LLVM code for the module:\n\n";
ProfileAnnotator PA(PI);
if (FunctionsToPrint.empty() || PrintAllCode)
M.print(outs(), &PA);
else
// Print just a subset of the functions.
for (std::set<Function*>::iterator I = FunctionsToPrint.begin(),
E = FunctionsToPrint.end(); I != E; ++I)
(*I)->print(outs(), &PA);
}
return false;
}
int main(int argc, char **argv) {
// Print a stack trace if we signal out.
sys::PrintStackTraceOnErrorSignal();
PrettyStackTraceProgram X(argc, argv);
LLVMContext &Context = getGlobalContext();
llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
cl::ParseCommandLineOptions(argc, argv, "llvm profile dump decoder\n");
// Read in the bitcode file...
std::string ErrorMessage;
Module *M = 0;
if (MemoryBuffer *Buffer = MemoryBuffer::getFileOrSTDIN(BitcodeFile,
&ErrorMessage)) {
M = ParseBitcodeFile(Buffer, Context, &ErrorMessage);
delete Buffer;
}
if (M == 0) {
errs() << argv[0] << ": " << BitcodeFile << ": "
<< ErrorMessage << "\n";
return 1;
}
// Read the profiling information. This is redundant since we load it again
// using the standard profile info provider pass, but for now this gives us
// access to additional information not exposed via the ProfileInfo
// interface.
ProfileInfoLoader PIL(argv[0], ProfileDataFile, *M);
// Run the printer pass.
PassManager PassMgr;
PassMgr.add(createProfileLoaderPass(ProfileDataFile));
PassMgr.add(new ProfileInfoPrinterPass(PIL));
PassMgr.run(*M);
return 0;
}