1 //===- ProfileInfoLoad.cpp - Load profile information from disk -----------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // The ProfileInfoLoader class is used to load and represent profiling
11 // information read in from the dump file.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/Analysis/ProfileInfoLoader.h"
16 #include "llvm/Analysis/ProfileInfoTypes.h"
17 #include "llvm/Module.h"
18 #include "llvm/InstrTypes.h"
19 #include "llvm/Support/raw_ostream.h"
20 #include <cstdio>
21 #include <cstdlib>
22 using namespace llvm;
23
24 // ByteSwap - Byteswap 'Var' if 'Really' is true.
25 //
ByteSwap(unsigned Var,bool Really)26 static inline unsigned ByteSwap(unsigned Var, bool Really) {
27 if (!Really) return Var;
28 return ((Var & (255U<< 0U)) << 24U) |
29 ((Var & (255U<< 8U)) << 8U) |
30 ((Var & (255U<<16U)) >> 8U) |
31 ((Var & (255U<<24U)) >> 24U);
32 }
33
AddCounts(unsigned A,unsigned B)34 static unsigned AddCounts(unsigned A, unsigned B) {
35 // If either value is undefined, use the other.
36 if (A == ProfileInfoLoader::Uncounted) return B;
37 if (B == ProfileInfoLoader::Uncounted) return A;
38 return A + B;
39 }
40
ReadProfilingBlock(const char * ToolName,FILE * F,bool ShouldByteSwap,std::vector<unsigned> & Data)41 static void ReadProfilingBlock(const char *ToolName, FILE *F,
42 bool ShouldByteSwap,
43 std::vector<unsigned> &Data) {
44 // Read the number of entries...
45 unsigned NumEntries;
46 if (fread(&NumEntries, sizeof(unsigned), 1, F) != 1) {
47 errs() << ToolName << ": data packet truncated!\n";
48 perror(0);
49 exit(1);
50 }
51 NumEntries = ByteSwap(NumEntries, ShouldByteSwap);
52
53 // Read the counts...
54 std::vector<unsigned> TempSpace(NumEntries);
55
56 // Read in the block of data...
57 if (fread(&TempSpace[0], sizeof(unsigned)*NumEntries, 1, F) != 1) {
58 errs() << ToolName << ": data packet truncated!\n";
59 perror(0);
60 exit(1);
61 }
62
63 // Make sure we have enough space... The space is initialised to -1 to
64 // facitiltate the loading of missing values for OptimalEdgeProfiling.
65 if (Data.size() < NumEntries)
66 Data.resize(NumEntries, ProfileInfoLoader::Uncounted);
67
68 // Accumulate the data we just read into the data.
69 if (!ShouldByteSwap) {
70 for (unsigned i = 0; i != NumEntries; ++i) {
71 Data[i] = AddCounts(TempSpace[i], Data[i]);
72 }
73 } else {
74 for (unsigned i = 0; i != NumEntries; ++i) {
75 Data[i] = AddCounts(ByteSwap(TempSpace[i], true), Data[i]);
76 }
77 }
78 }
79
80 const unsigned ProfileInfoLoader::Uncounted = ~0U;
81
82 // ProfileInfoLoader ctor - Read the specified profiling data file, exiting the
83 // program if the file is invalid or broken.
84 //
ProfileInfoLoader(const char * ToolName,const std::string & Filename,Module & TheModule)85 ProfileInfoLoader::ProfileInfoLoader(const char *ToolName,
86 const std::string &Filename,
87 Module &TheModule) :
88 Filename(Filename),
89 M(TheModule), Warned(false) {
90 FILE *F = fopen(Filename.c_str(), "rb");
91 if (F == 0) {
92 errs() << ToolName << ": Error opening '" << Filename << "': ";
93 perror(0);
94 exit(1);
95 }
96
97 // Keep reading packets until we run out of them.
98 unsigned PacketType;
99 while (fread(&PacketType, sizeof(unsigned), 1, F) == 1) {
100 // If the low eight bits of the packet are zero, we must be dealing with an
101 // endianness mismatch. Byteswap all words read from the profiling
102 // information.
103 bool ShouldByteSwap = (char)PacketType == 0;
104 PacketType = ByteSwap(PacketType, ShouldByteSwap);
105
106 switch (PacketType) {
107 case ArgumentInfo: {
108 unsigned ArgLength;
109 if (fread(&ArgLength, sizeof(unsigned), 1, F) != 1) {
110 errs() << ToolName << ": arguments packet truncated!\n";
111 perror(0);
112 exit(1);
113 }
114 ArgLength = ByteSwap(ArgLength, ShouldByteSwap);
115
116 // Read in the arguments...
117 std::vector<char> Chars(ArgLength+4);
118
119 if (ArgLength)
120 if (fread(&Chars[0], (ArgLength+3) & ~3, 1, F) != 1) {
121 errs() << ToolName << ": arguments packet truncated!\n";
122 perror(0);
123 exit(1);
124 }
125 CommandLines.push_back(std::string(&Chars[0], &Chars[ArgLength]));
126 break;
127 }
128
129 case FunctionInfo:
130 ReadProfilingBlock(ToolName, F, ShouldByteSwap, FunctionCounts);
131 break;
132
133 case BlockInfo:
134 ReadProfilingBlock(ToolName, F, ShouldByteSwap, BlockCounts);
135 break;
136
137 case EdgeInfo:
138 ReadProfilingBlock(ToolName, F, ShouldByteSwap, EdgeCounts);
139 break;
140
141 case OptEdgeInfo:
142 ReadProfilingBlock(ToolName, F, ShouldByteSwap, OptimalEdgeCounts);
143 break;
144
145 case BBTraceInfo:
146 ReadProfilingBlock(ToolName, F, ShouldByteSwap, BBTrace);
147 break;
148
149 default:
150 errs() << ToolName << ": Unknown packet type #" << PacketType << "!\n";
151 exit(1);
152 }
153 }
154
155 fclose(F);
156 }
157
158