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Diffstat (limited to 'lib/Analysis/ProfileDataLoader.cpp')
-rw-r--r-- | lib/Analysis/ProfileDataLoader.cpp | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/lib/Analysis/ProfileDataLoader.cpp b/lib/Analysis/ProfileDataLoader.cpp new file mode 100644 index 0000000..0006492 --- /dev/null +++ b/lib/Analysis/ProfileDataLoader.cpp @@ -0,0 +1,186 @@ +//===- ProfileDataLoader.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 ProfileDataLoader class is used to load raw profiling data from the dump +// file. +// +//===----------------------------------------------------------------------===// + +#include "llvm/Module.h" +#include "llvm/InstrTypes.h" +#include "llvm/Analysis/ProfileDataLoader.h" +#include "llvm/Analysis/ProfileDataTypes.h" +#include "llvm/Support/raw_ostream.h" +#include <cstdio> +#include <cstdlib> +using namespace llvm; + +namespace llvm { + +template<> +char ProfileDataT<Function,BasicBlock>::ID = 0; + +raw_ostream& operator<<(raw_ostream &O, const Function *F) { + return O << F->getName(); +} + +raw_ostream& operator<<(raw_ostream &O, const BasicBlock *BB) { + return O << BB->getName(); +} + +raw_ostream& operator<<(raw_ostream &O, std::pair<const BasicBlock *, const BasicBlock *> E) { + O << "("; + + if (E.first) + O << E.first; + else + O << "0"; + + O << ","; + + if (E.second) + O << E.second; + else + O << "0"; + + return O << ")"; +} + +} // namespace llvm + +/// ByteSwap - Byteswap 'Var' if 'Really' is true. Required when the compiler +/// host and target have different endianness. +static inline unsigned ByteSwap(unsigned Var, bool Really) { + if (!Really) return Var; + return ((Var & (255U<< 0U)) << 24U) | + ((Var & (255U<< 8U)) << 8U) | + ((Var & (255U<<16U)) >> 8U) | + ((Var & (255U<<24U)) >> 24U); +} + +/// AddCounts - Add 'A' and 'B', accounting for the fact that the value of one +/// (or both) may not be defined. +static unsigned AddCounts(unsigned A, unsigned B) { + // If either value is undefined, use the other. + // Undefined + undefined = undefined. + if (A == ProfileDataLoader::Uncounted) return B; + if (B == ProfileDataLoader::Uncounted) return A; + + // Saturate to the maximum storable value. This could change taken/nottaken + // ratios, but is presumably better than wrapping and thus potentially + // inverting ratios. + unsigned long long tmp = (unsigned long long)A + (unsigned long long)B; + if (tmp > (unsigned long long)ProfileDataLoader::MaxCount) + tmp = ProfileDataLoader::MaxCount; + return (unsigned)tmp; +} + +/// ReadProfilingData - Load 'NumEntries' items of type 'T' from file 'F' +template <typename T> +static void ReadProfilingData(const char *ToolName, FILE *F, + std::vector<T> &Data, size_t NumEntries) { + // Read in the block of data... + if (fread(&Data[0], sizeof(T), NumEntries, F) != NumEntries) { + errs() << ToolName << ": profiling data truncated!\n"; + perror(0); + exit(1); + } +} + +/// ReadProfilingNumEntries - Read how many entries are in this profiling data +/// packet. +static unsigned ReadProfilingNumEntries(const char *ToolName, FILE *F, + bool ShouldByteSwap) { + std::vector<unsigned> NumEntries(1); + ReadProfilingData<unsigned>(ToolName, F, NumEntries, 1); + return ByteSwap(NumEntries[0], ShouldByteSwap); +} + +/// ReadProfilingBlock - Read the number of entries in the next profiling data +/// packet and then accumulate the entries into 'Data'. +static void ReadProfilingBlock(const char *ToolName, FILE *F, + bool ShouldByteSwap, + std::vector<unsigned> &Data) { + // Read the number of entries... + unsigned NumEntries = ReadProfilingNumEntries(ToolName, F, ShouldByteSwap); + + // Read in the data. + std::vector<unsigned> TempSpace(NumEntries); + ReadProfilingData<unsigned>(ToolName, F, TempSpace, (size_t)NumEntries); + + // Make sure we have enough space ... + if (Data.size() < NumEntries) + Data.resize(NumEntries, ProfileDataLoader::Uncounted); + + // Accumulate the data we just read into the existing data. + for (unsigned i = 0; i < NumEntries; ++i) { + Data[i] = AddCounts(ByteSwap(TempSpace[i], ShouldByteSwap), Data[i]); + } +} + +/// ReadProfilingArgBlock - Read the command line arguments that the progam was +/// run with when the current profiling data packet(s) were generated. +static void ReadProfilingArgBlock(const char *ToolName, FILE *F, + bool ShouldByteSwap, + std::vector<std::string> &CommandLines) { + // Read the number of bytes ... + unsigned ArgLength = ReadProfilingNumEntries(ToolName, F, ShouldByteSwap); + + // Read in the arguments (if there are any to read). Round up the length to + // the nearest 4-byte multiple. + std::vector<char> Args(ArgLength+4); + if (ArgLength) + ReadProfilingData<char>(ToolName, F, Args, (ArgLength+3) & ~3); + + // Store the arguments. + CommandLines.push_back(std::string(&Args[0], &Args[ArgLength])); +} + +const unsigned ProfileDataLoader::Uncounted = ~0U; +const unsigned ProfileDataLoader::MaxCount = ~0U - 1U; + +/// ProfileDataLoader ctor - Read the specified profiling data file, exiting +/// the program if the file is invalid or broken. +ProfileDataLoader::ProfileDataLoader(const char *ToolName, + const std::string &Filename) + : Filename(Filename) { + FILE *F = fopen(Filename.c_str(), "rb"); + if (F == 0) { + errs() << 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. This can happen when the compiler host and target have + // different endianness. + bool ShouldByteSwap = (char)PacketType == 0; + PacketType = ByteSwap(PacketType, ShouldByteSwap); + + switch (PacketType) { + case ArgumentInfo: + ReadProfilingArgBlock(ToolName, F, ShouldByteSwap, CommandLines); + break; + + case EdgeInfo: + ReadProfilingBlock(ToolName, F, ShouldByteSwap, EdgeCounts); + break; + + default: + errs() << ToolName << ": Unknown packet type #" << PacketType << "!\n"; + exit(1); + } + } + + fclose(F); +} |