summaryrefslogtreecommitdiff
path: root/lib/Analysis/ProfileInfoLoader.cpp
blob: 4a9e17cd86af372fd797120e75f6ef31c48a7c95 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
//===- 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/InstrTypes.h"
#include "llvm/Module.h"
#include "llvm/Support/raw_ostream.h"
#include <cstdio>
#include <cstdlib>
using namespace llvm;

// ByteSwap - Byteswap 'Var' if 'Really' is true.
//
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);
}

static unsigned AddCounts(unsigned A, unsigned B) {
  // If either value is undefined, use the other.
  if (A == ProfileInfoLoader::Uncounted) return B;
  if (B == ProfileInfoLoader::Uncounted) return A;
  return A + B;
}

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) {
    errs() << 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) {
    errs() << ToolName << ": data packet truncated!\n";
    perror(0);
    exit(1);
  }

  // Make sure we have enough space... The space is initialised to -1 to
  // facitiltate the loading of missing values for OptimalEdgeProfiling.
  if (Data.size() < NumEntries)
    Data.resize(NumEntries, ProfileInfoLoader::Uncounted);

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

const unsigned ProfileInfoLoader::Uncounted = ~0U;

// 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)
  : 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.
    bool ShouldByteSwap = (char)PacketType == 0;
    PacketType = ByteSwap(PacketType, ShouldByteSwap);

    switch (PacketType) {
    case ArgumentInfo: {
      unsigned ArgLength;
      if (fread(&ArgLength, sizeof(unsigned), 1, F) != 1) {
        errs() << 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) {
          errs() << 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 OptEdgeInfo:
      ReadProfilingBlock(ToolName, F, ShouldByteSwap, OptimalEdgeCounts);
      break;

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

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

  fclose(F);
}