LLVM OpenMP* Runtime Library
kmp_stats_timing.cpp
1 
6 //===----------------------------------------------------------------------===//
7 //
8 // The LLVM Compiler Infrastructure
9 //
10 // This file is dual licensed under the MIT and the University of Illinois Open
11 // Source Licenses. See LICENSE.txt for details.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 
16 #include <stdlib.h>
17 #include <unistd.h>
18 
19 #include <iostream>
20 #include <iomanip>
21 #include <sstream>
22 
23 #include "kmp_stats_timing.h"
24 
25 using namespace std;
26 
27 #if KMP_OS_LINUX
28 # if KMP_MIC
29 double tsc_tick_count::tick_time()
30 {
31  // pretty bad assumption of 1GHz clock for MIC
32  return 1/((double)1000*1.e6);
33 }
34 # else
35 # include <string.h>
36 // Extract the value from the CPUID information
37 double tsc_tick_count::tick_time()
38 {
39  static double result = 0.0;
40 
41  if (result == 0.0)
42  {
43  int cpuinfo[4];
44  char brand[256];
45 
46  __cpuid(cpuinfo, 0x80000000);
47  memset(brand, 0, sizeof(brand));
48  int ids = cpuinfo[0];
49 
50  for (unsigned int i=2; i<(ids^0x80000000)+2; i++)
51  __cpuid(brand+(i-2)*sizeof(cpuinfo), i | 0x80000000);
52 
53  char * start = &brand[0];
54  for (;*start == ' '; start++)
55  ;
56 
57  char * end = brand + KMP_STRLEN(brand) - 3;
58  uint64_t multiplier;
59 
60  if (*end == 'M') multiplier = 1000LL*1000LL;
61  else if (*end == 'G') multiplier = 1000LL*1000LL*1000LL;
62  else if (*end == 'T') multiplier = 1000LL*1000LL*1000LL*1000LL;
63  else
64  {
65  cout << "Error determining multiplier '" << *end << "'\n";
66  exit (-1);
67  }
68  *end = 0;
69  while (*end != ' ') end--;
70  end++;
71 
72  double freq = strtod(end, &start);
73  if (freq == 0.0)
74  {
75  cout << "Error calculating frequency " << end << "\n";
76  exit (-1);
77  }
78 
79  result = ((double)1.0)/(freq * multiplier);
80  }
81  return result;
82 }
83 # endif
84 #endif
85 
86 static bool useSI = true;
87 
88 // Return a formatted string after normalising the value into
89 // engineering style and using a suitable unit prefix (e.g. ms, us, ns).
90 std::string formatSI(double interval, int width, char unit)
91 {
92  std::stringstream os;
93 
94  if (useSI)
95  {
96  // Preserve accuracy for small numbers, since we only multiply and the positive powers
97  // of ten are precisely representable.
98  static struct { double scale; char prefix; } ranges[] = {
99  {1.e12,'f'},
100  {1.e9, 'p'},
101  {1.e6, 'n'},
102  {1.e3, 'u'},
103  {1.0, 'm'},
104  {1.e-3,' '},
105  {1.e-6,'k'},
106  {1.e-9,'M'},
107  {1.e-12,'G'},
108  {1.e-15,'T'},
109  {1.e-18,'P'},
110  {1.e-21,'E'},
111  {1.e-24,'Z'},
112  {1.e-27,'Y'}
113  };
114 
115  if (interval == 0.0)
116  {
117  os << std::setw(width-3) << std::right << "0.00" << std::setw(3) << unit;
118  return os.str();
119  }
120 
121  bool negative = false;
122  if (interval < 0.0)
123  {
124  negative = true;
125  interval = -interval;
126  }
127 
128  for (int i=0; i<(int)(sizeof(ranges)/sizeof(ranges[0])); i++)
129  {
130  if (interval*ranges[i].scale < 1.e0)
131  {
132  interval = interval * 1000.e0 * ranges[i].scale;
133  os << std::fixed << std::setprecision(2) << std::setw(width-3) << std::right <<
134  (negative ? -interval : interval) << std::setw(2) << ranges[i].prefix << std::setw(1) << unit;
135 
136  return os.str();
137  }
138  }
139  }
140  os << std::setprecision(2) << std::fixed << std::right << std::setw(width-3) << interval << std::setw(3) << unit;
141 
142  return os.str();
143 }
144 
145 tsc_tick_count::tsc_interval_t computeLastInLastOutInterval(timePair * times, int nTimes)
146 {
147  timePair lastTimes = times[0];
148  tsc_tick_count * startp = lastTimes.get_startp();
149  tsc_tick_count * endp = lastTimes.get_endp();
150 
151  for (int i=1; i<nTimes; i++)
152  {
153  (*startp) = startp->later(times[i].get_start());
154  (*endp) = endp->later (times[i].get_end());
155  }
156 
157  return lastTimes.duration();
158 }
159 
160 std::string timePair::format() const
161 {
162  std::ostringstream oss;
163 
164  oss << start.getValue() << ":" << end.getValue() << " = " << (end-start).getValue();
165 
166  return oss.str();
167 }