Support customizable units in output

Author: gonzalobg

src/Unit.h

@@ -0,0 +1,51 @@
+#pragma once
+#include <iostream>
+
+enum { MegaByte, GigaByte, MibiByte, GibiByte };
+
+// Units for output:
+struct Unit {
+  int value;
+  Unit(int v) : value(v) {}
+  double fmt(double bytes) {
+    switch(value) {
+    case MibiByte: return pow(2.0, -20.0) * bytes;
+    case MegaByte: return 1.0E-6 * bytes;
+    case GibiByte: return pow(2.0, -30.0) * bytes;
+    case GigaByte: return 1.0E-9 * bytes;
+    default: std::cerr << "Unimplemented!" << std::endl; abort();
+    }
+  }
+  char const* str() {
+    switch(value) {
+    case MibiByte: return "MiB";
+    case MegaByte: return "MB";
+    case GibiByte: return "GiB";
+    case GigaByte: return "GB";
+    default: std::cerr << "Unimplemented!" << std::endl; abort();
+    }
+  }
+  Unit kibi() {
+    switch(value) {
+    case MegaByte: return Unit(MibiByte);
+    case GigaByte: return Unit(GibiByte);
+    default: return *this;
+    }
+  }
+  Unit byte() {
+    switch(value) {
+    case MibiByte: return Unit(MegaByte);
+    case GibiByte: return Unit(GigaByte);
+    default: return *this;
+    }
+  }
+  char const* lower() {
+    switch(value) {
+    case MibiByte: return "mibytes";
+    case MegaByte: return "mbytes";
+    case GibiByte: return "gibytes";
+    case GigaByte: return "gbytes";
+    default: std::cerr << "Unimplemented!" << std::endl; abort();
+    }
+  }
+};

src/main.cpp

@@ -18,6 +18,7 @@
 
 #include "Stream.h"
 #include "StreamModels.h"
+#include "Unit.h"
 
 using namespace std;
 
@@ -27,7 +28,7 @@ unsigned int num_times = 100;
 unsigned int deviceIndex = 0;
 bool use_float = false;
 bool output_as_csv = false;
-bool mibibytes = false;
+Unit unit = MegaByte;
 string csv_separator = ",";
 
 // Benchmarks:
@@ -86,9 +87,6 @@ void check_solution(const unsigned int ntimes, vector<T>& a, vector<T>& b, vecto
 template <typename T>
 void run();
 
-// Units for output:
-enum class Unit { Mega, Giga };
-
 void parseArguments(int argc, char *argv[]);
 
 int main(int argc, char *argv[])
@@ -155,31 +153,16 @@ void run()
   streamsize ss = cout.precision();
 
   // Formatting utilities:
-  auto fmt_unit = [](double bytes, Unit unit = Unit::Mega) {
-    switch(unit) {
-    case Unit::Mega: return (mibibytes? pow(2.0, -20.0) : 1.0E-6) * bytes;
-    case Unit::Giga: return (mibibytes? pow(2.0, -30.0) : 1.0E-9) * bytes;
-    default: cerr << "Unimplemented!" << endl; abort();
-    }
-  };
-  auto unit_label = [](Unit unit = Unit::Mega) {
-    switch(unit) {
-    case Unit::Mega: return mibibytes? "MiB" : "MB";
-    case Unit::Giga: return mibibytes? "GiB" : "GB";
-    default: cerr << "Unimplemented!" << endl; abort();
-    }
-  };
-  auto fmt_bw = [&](size_t weight, double dt, Unit unit = Unit::Mega) {
-    return fmt_unit((weight * sizeof(T) * ARRAY_SIZE)/dt, unit);
+  auto fmt_bw = [&](size_t weight, double dt) {
+    return unit.fmt((weight * sizeof(T) * ARRAY_SIZE)/dt);
   };
-  // Output formatting:
   auto fmt_csv_header = [] {
     cout
       << "function" << csv_separator
       << "num_times" << csv_separator
       << "n_elements" << csv_separator
       << "sizeof" << csv_separator
-      << ((mibibytes) ? "max_mibytes_per_sec" : "max_mbytes_per_sec") << csv_separator
+      << "max_" << unit.lower() << "_per_sec" << csv_separator
       << "min_runtime" << csv_separator
       << "max_runtime" << csv_separator
       << "avg_runtime" << endl;
@@ -224,10 +207,8 @@ void run()
 
     size_t nbytes = ARRAY_SIZE*sizeof(T);
     cout << setprecision(1) << fixed
-	 << "Array size: " << fmt_unit(nbytes, Unit::Mega) << " " << unit_label(Unit::Mega)
-	 << " (=" << fmt_unit(nbytes, Unit::Giga) << " " << unit_label(Unit::Giga) << ")" << endl;
-    cout << "Total size: " << fmt_unit(3.0*nbytes, Unit::Mega) << " " << unit_label(Unit::Mega)
-	 << " (=" << fmt_unit(3.0*nbytes, Unit::Giga) << " " << unit_label(Unit::Giga) << ")" << endl;
+	 << "Array size: " << unit.fmt(nbytes) << " " << unit.str() << endl;
+    cout << "Total size: " << unit.fmt(3.0*nbytes) << " " << unit.str() << endl;
     cout.precision(ss);
   }
 
@@ -256,22 +237,14 @@ void run()
   {
     cout << "Init: "
       << setw(7)
-      << initElapsedS
-      << " s (="
-      << initBWps
-      << (mibibytes ? " MiBytes/sec" : " MBytes/sec")
-      << ")" << endl;
+      << initElapsedS << " s (=" << initBWps << " " << unit.str() << "/s" << ")" << endl;
     cout << "Read: "
       << setw(7)
-      << readElapsedS
-      << " s (="
-      << readBWps
-      << (mibibytes ? " MiBytes/sec" : " MBytes/sec")
-      << ")" << endl;
+      << readElapsedS << " s (=" << readBWps << " " << unit.str() << "/s" << ")" << endl;
 
     cout
       << left << setw(12) << "Function"
-      << left << setw(12) << ((mibibytes) ? "MiBytes/sec" : "MBytes/sec")
+      << left << setw(12) << (string(unit.str()) + "/s")
       << left << setw(12) << "Min (sec)"
       << left << setw(12) << "Max"
       << left << setw(12) << "Average"
@@ -459,7 +432,19 @@ void parseArguments(int argc, char *argv[])
     }
     else if (!string("--mibibytes").compare(argv[i]))
     {
-      mibibytes = true;
+      unit = Unit(MibiByte);
+    }
+    else if (!string("--megabytes").compare(argv[i]))
+    {
+      unit = Unit(MegaByte);
+    }
+    else if (!string("--gibibytes").compare(argv[i]))
+    {
+      unit = Unit(GibiByte);
+    }
+    else if (!string("--gigabytes").compare(argv[i]))
+    {
+      unit = Unit(GigaByte);
     }
     else if (!string("--help").compare(argv[i]) ||
              !string("-h").compare(argv[i]))
@@ -476,7 +461,10 @@ void parseArguments(int argc, char *argv[])
       cout << "  -o  --only       NAME    Only run one benchmark (see --print-names)" << endl;
       cout << "      --print-names        Prints all available benchmark names" << endl;
       cout << "      --csv                Output as csv table" << endl;
+      cout << "      --megabytes          Use MB=10^6 for bandwidth calculation (default)" << endl;
       cout << "      --mibibytes          Use MiB=2^20 for bandwidth calculation (default MB=10^6)" << endl;
+      cout << "      --gigibytes          Use GiB=2^30 for bandwidth calculation (default MB=10^6)" << endl;
+      cout << "      --gigabytes          Use GB=10^9 for bandwidth calculation (default MB=10^6)" << endl;
       cout << endl;
       exit(EXIT_SUCCESS);
     }