lib/Analysis/ProfileInfoLoader.cpp - llvm - Git at Google

 //===- ProfileInfoLoad.cpp - Load profile information from disk -----------===//
 //
 //                      The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // The ProfileInfoLoader class is used to load and represent profiling
 // information read in from the dump file.
 //
 //===----------------------------------------------------------------------===//

 #include "llvm/Analysis/ProfileInfoLoader.h"
 #include "llvm/Analysis/ProfileInfoTypes.h"
 #include "llvm/Module.h"
 #include "llvm/InstrTypes.h"
 #include "llvm/Support/Streams.h"
 #include <cstdio>
 #include <map>
 using namespace llvm;

 // ByteSwap - Byteswap 'Var' if 'Really' is true.
 //
 static inline unsigned ByteSwap(unsigned Var, bool Really) {
   if (!Really) return Var;
   return ((Var & (255<< 0)) << 24) |
          ((Var & (255<< 8)) <<  8) |
          ((Var & (255<<16)) >>  8) |
          ((Var & (255<<24)) >> 24);
 }

 static void ReadProfilingBlock(const char *ToolName, FILE *F,
                                bool ShouldByteSwap,
                                std::vector<unsigned> &Data) {
   // Read the number of entries...
   unsigned NumEntries;
   if (fread(&NumEntries, sizeof(unsigned), 1, F) != 1) {
     cerr << ToolName << ": data packet truncated!\n";
     perror(0);
     exit(1);
   }
   NumEntries = ByteSwap(NumEntries, ShouldByteSwap);

   // Read the counts...
   std::vector<unsigned> TempSpace(NumEntries);

   // Read in the block of data...
   if (fread(&TempSpace[0], sizeof(unsigned)*NumEntries, 1, F) != 1) {
     cerr << ToolName << ": data packet truncated!\n";
     perror(0);
     exit(1);
   }

   // Make sure we have enough space...
   if (Data.size() < NumEntries)
     Data.resize(NumEntries);

   // Accumulate the data we just read into the data.
   if (!ShouldByteSwap) {
     for (unsigned i = 0; i != NumEntries; ++i)
       Data[i] += TempSpace[i];
   } else {
     for (unsigned i = 0; i != NumEntries; ++i)
       Data[i] += ByteSwap(TempSpace[i], true);
   }
 }

 // ProfileInfoLoader ctor - Read the specified profiling data file, exiting the
 // program if the file is invalid or broken.
 //
 ProfileInfoLoader::ProfileInfoLoader(const char *ToolName,
                                      const std::string &Filename,
                                      Module &TheModule) : M(TheModule) {
   FILE *F = fopen(Filename.c_str(), "r");
   if (F == 0) {
     cerr << ToolName << ": Error opening '" << Filename << "': ";
     perror(0);
     exit(1);
   }

   // Keep reading packets until we run out of them.
   unsigned PacketType;
   while (fread(&PacketType, sizeof(unsigned), 1, F) == 1) {
     // If the low eight bits of the packet are zero, we must be dealing with an
     // endianness mismatch.  Byteswap all words read from the profiling
     // information.
     bool ShouldByteSwap = (char)PacketType == 0;
     PacketType = ByteSwap(PacketType, ShouldByteSwap);

     switch (PacketType) {
     case ArgumentInfo: {
       unsigned ArgLength;
       if (fread(&ArgLength, sizeof(unsigned), 1, F) != 1) {
         cerr << ToolName << ": arguments packet truncated!\n";
         perror(0);
         exit(1);
       }
       ArgLength = ByteSwap(ArgLength, ShouldByteSwap);

       // Read in the arguments...
       std::vector<char> Chars(ArgLength+4);

       if (ArgLength)
         if (fread(&Chars[0], (ArgLength+3) & ~3, 1, F) != 1) {
           cerr << ToolName << ": arguments packet truncated!\n";
           perror(0);
           exit(1);
         }
       CommandLines.push_back(std::string(&Chars[0], &Chars[ArgLength]));
       break;
     }

     case FunctionInfo:
       ReadProfilingBlock(ToolName, F, ShouldByteSwap, FunctionCounts);
       break;

     case BlockInfo:
       ReadProfilingBlock(ToolName, F, ShouldByteSwap, BlockCounts);
       break;

     case EdgeInfo:
       ReadProfilingBlock(ToolName, F, ShouldByteSwap, EdgeCounts);
       break;

     case BBTraceInfo:
       ReadProfilingBlock(ToolName, F, ShouldByteSwap, BBTrace);
       break;

     default:
       cerr << ToolName << ": Unknown packet type #" << PacketType << "!\n";
       exit(1);
     }
   }

   fclose(F);
 }


 // getFunctionCounts - This method is used by consumers of function counting
 // information.  If we do not directly have function count information, we
 // compute it from other, more refined, types of profile information.
 //
 void ProfileInfoLoader::getFunctionCounts(std::vector<std::pair<Function*,
                                                       unsigned> > &Counts) {
   if (FunctionCounts.empty()) {
     if (hasAccurateBlockCounts()) {
       // Synthesize function frequency information from the number of times
       // their entry blocks were executed.
       std::vector<std::pair<BasicBlock*, unsigned> > BlockCounts;
       getBlockCounts(BlockCounts);

       for (unsigned i = 0, e = BlockCounts.size(); i != e; ++i)
         if (&BlockCounts[i].first->getParent()->getEntryBlock() ==
             BlockCounts[i].first)
           Counts.push_back(std::make_pair(BlockCounts[i].first->getParent(),
                                           BlockCounts[i].second));
     } else {
       cerr << "Function counts are not available!\n";
     }
     return;
   }

   unsigned Counter = 0;
   for (Module::iterator I = M.begin(), E = M.end();
        I != E && Counter != FunctionCounts.size(); ++I)
     if (!I->isDeclaration())
       Counts.push_back(std::make_pair(I, FunctionCounts[Counter++]));
 }

 // getBlockCounts - This method is used by consumers of block counting
 // information.  If we do not directly have block count information, we
 // compute it from other, more refined, types of profile information.
 //
 void ProfileInfoLoader::getBlockCounts(std::vector<std::pair<BasicBlock*,
                                                          unsigned> > &Counts) {
   if (BlockCounts.empty()) {
     if (hasAccurateEdgeCounts()) {
       // Synthesize block count information from edge frequency information.
       // The block execution frequency is equal to the sum of the execution
       // frequency of all outgoing edges from a block.
       //
       // If a block has no successors, this will not be correct, so we have to
       // special case it. :(
       std::vector<std::pair<Edge, unsigned> > EdgeCounts;
       getEdgeCounts(EdgeCounts);

       std::map<BasicBlock*, unsigned> InEdgeFreqs;

       BasicBlock *LastBlock = 0;
       TerminatorInst *TI = 0;
       for (unsigned i = 0, e = EdgeCounts.size(); i != e; ++i) {
         if (EdgeCounts[i].first.first != LastBlock) {
           LastBlock = EdgeCounts[i].first.first;
           TI = LastBlock->getTerminator();
           Counts.push_back(std::make_pair(LastBlock, 0));
         }
         Counts.back().second += EdgeCounts[i].second;
         unsigned SuccNum = EdgeCounts[i].first.second;
         if (SuccNum >= TI->getNumSuccessors()) {
           static bool Warned = false;
           if (!Warned) {
             cerr << "WARNING: profile info doesn't seem to match"
                  << " the program!\n";
             Warned = true;
           }
         } else {
           // If this successor has no successors of its own, we will never
           // compute an execution count for that block.  Remember the incoming
           // edge frequencies to add later.
           BasicBlock *Succ = TI->getSuccessor(SuccNum);
           if (Succ->getTerminator()->getNumSuccessors() == 0)
             InEdgeFreqs[Succ] += EdgeCounts[i].second;
         }
       }

       // Now we have to accumulate information for those blocks without
       // successors into our table.
       for (std::map<BasicBlock*, unsigned>::iterator I = InEdgeFreqs.begin(),
              E = InEdgeFreqs.end(); I != E; ++I) {
         unsigned i = 0;
         for (; i != Counts.size() && Counts[i].first != I->first; ++i)
           /*empty*/;
         if (i == Counts.size()) Counts.push_back(std::make_pair(I->first, 0));
         Counts[i].second += I->second;
       }

     } else {
       cerr << "Block counts are not available!\n";
     }
     return;
   }

   unsigned Counter = 0;
   for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F)
     for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
       Counts.push_back(std::make_pair(BB, BlockCounts[Counter++]));
       if (Counter == BlockCounts.size())
         return;
     }
 }

 // getEdgeCounts - This method is used by consumers of edge counting
 // information.  If we do not directly have edge count information, we compute
 // it from other, more refined, types of profile information.
 //
 void ProfileInfoLoader::getEdgeCounts(std::vector<std::pair<Edge,
                                                   unsigned> > &Counts) {
   if (EdgeCounts.empty()) {
     cerr << "Edge counts not available, and no synthesis "
          << "is implemented yet!\n";
     return;
   }

   unsigned Counter = 0;
   for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F)
     for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
       for (unsigned i = 0, e = BB->getTerminator()->getNumSuccessors();
            i != e; ++i) {
         Counts.push_back(std::make_pair(Edge(BB, i), EdgeCounts[Counter++]));
         if (Counter == EdgeCounts.size())
           return;
       }
 }

 // getBBTrace - This method is used by consumers of basic-block trace
 // information.
 //
 void ProfileInfoLoader::getBBTrace(std::vector<BasicBlock *> &Trace) {
   if (BBTrace.empty ()) {
     cerr << "Basic block trace is not available!\n";
     return;
   }
   cerr << "Basic block trace loading is not implemented yet!\n";
 }
	//===- ProfileInfoLoad.cpp - Load profile information from disk -----------===//
	//
	// The LLVM Compiler Infrastructure
	//
	// This file is distributed under the University of Illinois Open Source
	// License. See LICENSE.TXT for details.
	//
	//===----------------------------------------------------------------------===//
	//
	// The ProfileInfoLoader class is used to load and represent profiling
	// information read in from the dump file.
	//
	//===----------------------------------------------------------------------===//

	#include "llvm/Analysis/ProfileInfoLoader.h"
	#include "llvm/Analysis/ProfileInfoTypes.h"
	#include "llvm/Module.h"
	#include "llvm/InstrTypes.h"
	#include "llvm/Support/Streams.h"
	#include <cstdio>
	#include <map>
	using namespace llvm;

	// ByteSwap - Byteswap 'Var' if 'Really' is true.
	//
	static inline unsigned ByteSwap(unsigned Var, bool Really) {
	if (!Really) return Var;
	return ((Var & (255<< 0)) << 24) \|
	((Var & (255<< 8)) << 8) \|
	((Var & (255<<16)) >> 8) \|
	((Var & (255<<24)) >> 24);
	}

	static void ReadProfilingBlock(const char ToolName, FILE F,
	bool ShouldByteSwap,
	std::vector<unsigned> &Data) {
	// Read the number of entries...
	unsigned NumEntries;
	if (fread(&NumEntries, sizeof(unsigned), 1, F) != 1) {
	cerr << ToolName << ": data packet truncated!\n";
	perror(0);
	exit(1);
	}
	NumEntries = ByteSwap(NumEntries, ShouldByteSwap);

	// Read the counts...
	std::vector<unsigned> TempSpace(NumEntries);

	// Read in the block of data...
	if (fread(&TempSpace[0], sizeof(unsigned)*NumEntries, 1, F) != 1) {
	cerr << ToolName << ": data packet truncated!\n";
	perror(0);
	exit(1);
	}

	// Make sure we have enough space...
	if (Data.size() < NumEntries)
	Data.resize(NumEntries);

	// Accumulate the data we just read into the data.
	if (!ShouldByteSwap) {
	for (unsigned i = 0; i != NumEntries; ++i)
	Data[i] += TempSpace[i];
	} else {
	for (unsigned i = 0; i != NumEntries; ++i)
	Data[i] += ByteSwap(TempSpace[i], true);
	}
	}

	// ProfileInfoLoader ctor - Read the specified profiling data file, exiting the
	// program if the file is invalid or broken.
	//
	ProfileInfoLoader::ProfileInfoLoader(const char *ToolName,
	const std::string &Filename,
	Module &TheModule) : M(TheModule) {
	FILE *F = fopen(Filename.c_str(), "r");
	if (F == 0) {
	cerr << ToolName << ": Error opening '" << Filename << "': ";
	perror(0);
	exit(1);
	}

	// Keep reading packets until we run out of them.
	unsigned PacketType;
	while (fread(&PacketType, sizeof(unsigned), 1, F) == 1) {
	// If the low eight bits of the packet are zero, we must be dealing with an
	// endianness mismatch. Byteswap all words read from the profiling
	// information.
	bool ShouldByteSwap = (char)PacketType == 0;
	PacketType = ByteSwap(PacketType, ShouldByteSwap);

	switch (PacketType) {
	case ArgumentInfo: {
	unsigned ArgLength;
	if (fread(&ArgLength, sizeof(unsigned), 1, F) != 1) {
	cerr << ToolName << ": arguments packet truncated!\n";
	perror(0);
	exit(1);
	}
	ArgLength = ByteSwap(ArgLength, ShouldByteSwap);

	// Read in the arguments...
	std::vector<char> Chars(ArgLength+4);

	if (ArgLength)
	if (fread(&Chars[0], (ArgLength+3) & ~3, 1, F) != 1) {
	cerr << ToolName << ": arguments packet truncated!\n";
	perror(0);
	exit(1);
	}
	CommandLines.push_back(std::string(&Chars[0], &Chars[ArgLength]));
	break;
	}

	case FunctionInfo:
	ReadProfilingBlock(ToolName, F, ShouldByteSwap, FunctionCounts);
	break;

	case BlockInfo:
	ReadProfilingBlock(ToolName, F, ShouldByteSwap, BlockCounts);
	break;

	case EdgeInfo:
	ReadProfilingBlock(ToolName, F, ShouldByteSwap, EdgeCounts);
	break;

	case BBTraceInfo:
	ReadProfilingBlock(ToolName, F, ShouldByteSwap, BBTrace);
	break;

	default:
	cerr << ToolName << ": Unknown packet type #" << PacketType << "!\n";
	exit(1);
	}
	}

	fclose(F);
	}


	// getFunctionCounts - This method is used by consumers of function counting
	// information. If we do not directly have function count information, we
	// compute it from other, more refined, types of profile information.
	//
	void ProfileInfoLoader::getFunctionCounts(std::vector<std::pair<Function*,
	unsigned> > &Counts) {
	if (FunctionCounts.empty()) {
	if (hasAccurateBlockCounts()) {
	// Synthesize function frequency information from the number of times
	// their entry blocks were executed.
	std::vector<std::pair<BasicBlock*, unsigned> > BlockCounts;
	getBlockCounts(BlockCounts);

	for (unsigned i = 0, e = BlockCounts.size(); i != e; ++i)
	if (&BlockCounts[i].first->getParent()->getEntryBlock() ==
	BlockCounts[i].first)
	Counts.push_back(std::make_pair(BlockCounts[i].first->getParent(),
	BlockCounts[i].second));
	} else {
	cerr << "Function counts are not available!\n";
	}
	return;
	}

	unsigned Counter = 0;
	for (Module::iterator I = M.begin(), E = M.end();
	I != E && Counter != FunctionCounts.size(); ++I)
	if (!I->isDeclaration())
	Counts.push_back(std::make_pair(I, FunctionCounts[Counter++]));
	}

	// getBlockCounts - This method is used by consumers of block counting
	// information. If we do not directly have block count information, we
	// compute it from other, more refined, types of profile information.
	//
	void ProfileInfoLoader::getBlockCounts(std::vector<std::pair<BasicBlock*,
	unsigned> > &Counts) {
	if (BlockCounts.empty()) {
	if (hasAccurateEdgeCounts()) {
	// Synthesize block count information from edge frequency information.
	// The block execution frequency is equal to the sum of the execution
	// frequency of all outgoing edges from a block.
	//
	// If a block has no successors, this will not be correct, so we have to
	// special case it. :(
	std::vector<std::pair<Edge, unsigned> > EdgeCounts;
	getEdgeCounts(EdgeCounts);

	std::map<BasicBlock*, unsigned> InEdgeFreqs;

	BasicBlock *LastBlock = 0;
	TerminatorInst *TI = 0;
	for (unsigned i = 0, e = EdgeCounts.size(); i != e; ++i) {
	if (EdgeCounts[i].first.first != LastBlock) {
	LastBlock = EdgeCounts[i].first.first;
	TI = LastBlock->getTerminator();
	Counts.push_back(std::make_pair(LastBlock, 0));
	}
	Counts.back().second += EdgeCounts[i].second;
	unsigned SuccNum = EdgeCounts[i].first.second;
	if (SuccNum >= TI->getNumSuccessors()) {
	static bool Warned = false;
	if (!Warned) {
	cerr << "WARNING: profile info doesn't seem to match"
	<< " the program!\n";
	Warned = true;
	}
	} else {
	// If this successor has no successors of its own, we will never
	// compute an execution count for that block. Remember the incoming
	// edge frequencies to add later.
	BasicBlock *Succ = TI->getSuccessor(SuccNum);
	if (Succ->getTerminator()->getNumSuccessors() == 0)
	InEdgeFreqs[Succ] += EdgeCounts[i].second;
	}
	}

	// Now we have to accumulate information for those blocks without
	// successors into our table.
	for (std::map<BasicBlock*, unsigned>::iterator I = InEdgeFreqs.begin(),
	E = InEdgeFreqs.end(); I != E; ++I) {
	unsigned i = 0;
	for (; i != Counts.size() && Counts[i].first != I->first; ++i)
	/empty/;
	if (i == Counts.size()) Counts.push_back(std::make_pair(I->first, 0));
	Counts[i].second += I->second;
	}

	} else {
	cerr << "Block counts are not available!\n";
	}
	return;
	}

	unsigned Counter = 0;
	for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F)
	for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
	Counts.push_back(std::make_pair(BB, BlockCounts[Counter++]));
	if (Counter == BlockCounts.size())
	return;
	}
	}

	// getEdgeCounts - This method is used by consumers of edge counting
	// information. If we do not directly have edge count information, we compute
	// it from other, more refined, types of profile information.
	//
	void ProfileInfoLoader::getEdgeCounts(std::vector<std::pair<Edge,
	unsigned> > &Counts) {
	if (EdgeCounts.empty()) {
	cerr << "Edge counts not available, and no synthesis "
	<< "is implemented yet!\n";
	return;
	}

	unsigned Counter = 0;
	for (Module::iterator F = M.begin(), E = M.end(); F != E; ++F)
	for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
	for (unsigned i = 0, e = BB->getTerminator()->getNumSuccessors();
	i != e; ++i) {
	Counts.push_back(std::make_pair(Edge(BB, i), EdgeCounts[Counter++]));
	if (Counter == EdgeCounts.size())
	return;
	}
	}

	// getBBTrace - This method is used by consumers of basic-block trace
	// information.
	//
	void ProfileInfoLoader::getBBTrace(std::vector<BasicBlock *> &Trace) {
	if (BBTrace.empty ()) {
	cerr << "Basic block trace is not available!\n";
	return;
	}
	cerr << "Basic block trace loading is not implemented yet!\n";
	}