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/IR/InstrTypes.h"
18 #include "llvm/IR/Module.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)85 ProfileInfoLoader::ProfileInfoLoader(const char *ToolName,
86 const std::string &Filename)
87 : Filename(Filename) {
88 FILE *F = fopen(Filename.c_str(), "rb");
89 if (F == 0) {
90 errs() << ToolName << ": Error opening '" << Filename << "': ";
91 perror(0);
92 exit(1);
93 }
94
95 // Keep reading packets until we run out of them.
96 unsigned PacketType;
97 while (fread(&PacketType, sizeof(unsigned), 1, F) == 1) {
98 // If the low eight bits of the packet are zero, we must be dealing with an
99 // endianness mismatch. Byteswap all words read from the profiling
100 // information.
101 bool ShouldByteSwap = (char)PacketType == 0;
102 PacketType = ByteSwap(PacketType, ShouldByteSwap);
103
104 switch (PacketType) {
105 case ArgumentInfo: {
106 unsigned ArgLength;
107 if (fread(&ArgLength, sizeof(unsigned), 1, F) != 1) {
108 errs() << ToolName << ": arguments packet truncated!\n";
109 perror(0);
110 exit(1);
111 }
112 ArgLength = ByteSwap(ArgLength, ShouldByteSwap);
113
114 // Read in the arguments...
115 std::vector<char> Chars(ArgLength+4);
116
117 if (ArgLength)
118 if (fread(&Chars[0], (ArgLength+3) & ~3, 1, F) != 1) {
119 errs() << ToolName << ": arguments packet truncated!\n";
120 perror(0);
121 exit(1);
122 }
123 CommandLines.push_back(std::string(&Chars[0], &Chars[ArgLength]));
124 break;
125 }
126
127 case FunctionInfo:
128 ReadProfilingBlock(ToolName, F, ShouldByteSwap, FunctionCounts);
129 break;
130
131 case BlockInfo:
132 ReadProfilingBlock(ToolName, F, ShouldByteSwap, BlockCounts);
133 break;
134
135 case EdgeInfo:
136 ReadProfilingBlock(ToolName, F, ShouldByteSwap, EdgeCounts);
137 break;
138
139 case OptEdgeInfo:
140 ReadProfilingBlock(ToolName, F, ShouldByteSwap, OptimalEdgeCounts);
141 break;
142
143 case BBTraceInfo:
144 ReadProfilingBlock(ToolName, F, ShouldByteSwap, BBTrace);
145 break;
146
147 default:
148 errs() << ToolName << ": Unknown packet type #" << PacketType << "!\n";
149 exit(1);
150 }
151 }
152
153 fclose(F);
154 }
155
156