Rename fletch -> dartino

pkg/fletchc/lib/program_info.dart

Index: pkg/fletchc/lib/program_info.dart
diff --git a/pkg/fletchc/lib/program_info.dart b/pkg/fletchc/lib/program_info.dart
deleted file mode 100644
index dfdecba005ab7536855b665341cf46a5054befef..0000000000000000000000000000000000000000
--- a/pkg/fletchc/lib/program_info.dart
+++ /dev/null
@@ -1,876 +0,0 @@
-// Copyright (c) 2015, the Dartino project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE.md file.
-
-library fletchc.program_info;
-
-import 'dart:async' show
-    Future,
-    Stream,
-    StreamSink;
-
-import 'dart:io' as io;
-
-import 'dart:io' show
-    BytesBuilder;
-
-import 'dart:convert' show
-    JSON,
-    LineSplitter,
-    UTF8;
-
-import 'dart:typed_data' show
-    Int32List,
-    Uint8List,
-    ByteData,
-    Endianness;
-
-import 'package:persistent/persistent.dart' show
-    Pair;
-
-import 'vm_commands.dart' show
-    WriteSnapshotResult;
-
-import 'fletch_system.dart' show
-    FletchClass,
-    FletchFunction,
-    FletchSystem;
-
-import 'src/fletch_selector.dart' show
-    FletchSelector;
-
-enum Configuration {
-  Offset64BitsDouble,
-  Offset64BitsFloat,
-  Offset32BitsDouble,
-  Offset32BitsFloat,
-}
-
-class ProgramInfo {
-  final List<String> _strings;
-
-  // Maps selector-id -> string-id
-  final List<int> _selectorNames;
-
-  // Maps configuration -> offset -> string-id
-  final Map<Configuration, Map<int, int>> _classNames;
-
-  // Maps configuration -> offset -> string-id
-  final Map<Configuration, Map<int, int>> _functionNames;
-
-  // Snapshot hashtag for validation.
-  final hashtag;
-
-  ProgramInfo(this._strings, this._selectorNames,
-              this._classNames, this._functionNames,
-              this.hashtag);
-
-  String classNameOfFunction(Configuration conf, int functionOffset) {
-    return _getString(_classNames[conf][functionOffset]);
-  }
-
-  String functionName(Configuration conf, int functionOffset) {
-    return _getString(_functionNames[conf][functionOffset]);
-  }
-
-  String className(Configuration conf, int classOffset) {
-    return _getString(_classNames[conf][classOffset]);
-  }
-
-  String selectorName(FletchSelector selector) {
-    return _getString(_selectorNames[selector.id]);
-  }
-
-  String _getString(int stringId) {
-    String name = null;
-    if (stringId != null && stringId != -1) {
-      name = _strings[stringId];
-      if (name == '') name = null;
-    }
-    return name;
-  }
-}
-
-abstract class ProgramInfoJson {
-  static String encode(ProgramInfo info, {List<Configuration> enabledConfigs}) {
-    if (enabledConfigs == null) {
-      enabledConfigs = Configuration.values;
-    }
-
-    Map<String, List<int>> buildTables(
-        Map<Configuration, Map<int, int>> offset2stringIds) {
-
-      List<int> convertMap(Configuration conf) {
-        if (enabledConfigs.contains(conf)) {
-          var map = offset2stringIds[conf];
-          List<int> list = new List<int>(map.length * 2);
-          int offset = 0;
-          map.forEach((int a, int b) {
-            list[offset++] = a;
-            list[offset++] = b;
-          });
-          return list;
-        } else {
-          return const [];
-        }
-      }
-
-      return {
-        'b64double': convertMap(Configuration.Offset64BitsDouble),
-        'b64float':  convertMap(Configuration.Offset64BitsFloat),
-        'b32double': convertMap(Configuration.Offset32BitsDouble),
-        'b32float':  convertMap(Configuration.Offset32BitsFloat),
-      };
-    }
-
-    return JSON.encode({
-      'strings': info._strings,
-      'selectors': info._selectorNames,
-      'class-names': buildTables(info._classNames),
-      'function-names' : buildTables(info._functionNames),
-      'hashtag': info.hashtag,
-    });
-  }
-
-  static ProgramInfo decode(String string) {
-    var json = JSON.decode(string);
-
-    Map<int, int> convertList(List<int> list) {
-      Map<int, int> map = {};
-      for (int i = 0; i < list.length; i += 2) {
-        map[list[i]] = list[i + 1];
-      }
-      return map;
-    }
-
-    var classNames = {
-      Configuration.Offset64BitsDouble :
-          convertList(json['class-names']['b64double']),
-      Configuration.Offset64BitsFloat:
-          convertList(json['class-names']['b64float']),
-      Configuration.Offset32BitsDouble :
-          convertList(json['class-names']['b32double']),
-      Configuration.Offset32BitsFloat :
-          convertList(json['class-names']['b32float']),
-    };
-
-    var functionNames = {
-      Configuration.Offset64BitsDouble :
-          convertList(json['function-names']['b64double']),
-      Configuration.Offset64BitsFloat:
-          convertList(json['function-names']['b64float']),
-      Configuration.Offset32BitsDouble :
-          convertList(json['function-names']['b32double']),
-      Configuration.Offset32BitsFloat :
-          convertList(json['function-names']['b32float']),
-    };
-
-    return new ProgramInfo(
-        json['strings'], json['selectors'],
-        classNames, functionNames,
-        json['hashtag']);
-  }
-}
-
-abstract class ProgramInfoBinary {
-  static const int _INVALID_INDEX = 0xffffff;
-  static final int _HEADER_LENGTH = 4 * (2 + 2 * Configuration.values.length);
-
-  static List<int> encode(ProgramInfo info,
-                          {List<Configuration> enabledConfigs}) {
-    if (enabledConfigs == null) {
-      enabledConfigs = Configuration.values;
-    }
-
-    List<int> stringOffsetsInStringTable = [];
-
-    void ensureEncodableAs24Bit(int number) {
-      if (number >= ((1 << 24) - 1)) {
-        throw new Exception(
-            "The binary program information format cannot encode offsets "
-            "larger than 16 MB (24 bits) at the moment.");
-      }
-    }
-
-    List<int> buildStringTable() {
-      BytesBuilder builder = new BytesBuilder();
-      for (int i = 0; i < info._strings.length; i++) {
-        stringOffsetsInStringTable.add(builder.length);
-        String name = info._strings[i];
-        if (name != null) {
-          builder.add(UTF8.encode(name));
-        }
-        builder.addByte(0);
-      }
-      return builder.takeBytes();
-    }
-
-    List<int> buildSelectorTable(List<int> stringIds) {
-      Uint8List bytes = new Uint8List(3 * stringIds.length);
-
-      int offset = 0;
-
-      void writeByte(int byte) {
-        bytes[offset++] = byte;
-      }
-
-      void writeNumber(int number) {
-        ensureEncodableAs24Bit(number);
-
-        // 0xffffff means -1
-        if (number == -1) number = _INVALID_INDEX;
-
-        writeByte(number & 0xff);
-        writeByte((number >> 8) & 0xff);
-        writeByte((number >> 16) & 0xff);
-      }
-
-      // We write tuples [program-offset, string-table-offset].
-      // So the user can use binary search using a program offset to find the
-      // string offset.
-      for (int i = 0; i < stringIds.length; i++) {
-        int stringId = stringIds[i];
-
-        if (stringId != -1) {
-          int stringOffset = stringOffsetsInStringTable[stringId];
-          writeNumber(stringOffset);
-        } else {
-          writeNumber(-1);
-        }
-      }
-
-      assert(offset == bytes.length);
-
-      return bytes;
-    }
-
-    List<int> buildOffsetTable(Map<int, int> map) {
-      Uint8List bytes = new Uint8List(2 * 3 * map.length);
-
-      int offset = 0;
-
-      void writeByte(int byte) {
-        bytes[offset++] = byte;
-      }
-
-      void writeNumber(int number) {
-        // 0xffffff means -1
-        ensureEncodableAs24Bit(number);
-
-        if (number == -1) number = _INVALID_INDEX;
-
-        writeByte(number & 0xff);
-        writeByte((number >> 8) & 0xff);
-        writeByte((number >> 16) & 0xff);
-      }
-
-      // We write tuples [program-offset, string-table-offset].
-      // So the user can use binary search using a program offset to find the
-      // string offset.
-      List<int> offsets = map.keys.toList()..sort();
-      for (int i = 0; i < offsets.length; i++) {
-        int offset = offsets[i];
-        int stringId = map[offset];
-
-        // We only make an entry for [offset] if there is a known string.
-        if (stringId != -1) {
-          int stringOffset = stringOffsetsInStringTable[stringId];
-          writeNumber(offset);
-          writeNumber(stringOffset);
-        }
-      }
-
-      return new Uint8List.view(bytes.buffer, 0, offset);
-    }
-
-    List<List<int>> tables = [];
-    tables.add(buildStringTable());
-    tables.add(buildSelectorTable(info._selectorNames));
-    for (Configuration conf in Configuration.values) {
-      if (enabledConfigs.contains(conf)) {
-        List<int> offsetTable = buildOffsetTable(info._classNames[conf]);
-        tables.add(offsetTable);
-      } else {
-        tables.add([]);
-      }
-    }
-    for (Configuration conf in Configuration.values) {
-      if (enabledConfigs.contains(conf)) {
-        List<int> offsetTable = buildOffsetTable(info._functionNames[conf]);
-        tables.add(offsetTable);
-      } else {
-        tables.add([]);
-      }
-    }
-
-    int tableLengths = tables.map((t) => t.length).fold(0, (a, b) => a + b);
-    int length = _HEADER_LENGTH + tableLengths;
-
-    Uint8List bytes = new Uint8List(length);
-    ByteData header = new ByteData.view(bytes.buffer);
-
-    int offset = 0;
-    writeLength(List<int> data) {
-      header.setUint32(offset, data.length, Endianness.LITTLE_ENDIAN);
-      offset += 4;
-    }
-    writeTable(List<int> data) {
-      bytes.setRange(offset, offset + data.length, data);
-      offset += data.length;
-    }
-
-    tables.forEach(writeLength);
-    assert(offset == _HEADER_LENGTH);
-    tables.forEach(writeTable);
-
-    return bytes;
-  }
-
-  static ProgramInfo decode(List<int> data) {
-    Uint8List bytes = new Uint8List.fromList(data);
-    ByteData header = new ByteData.view(bytes.buffer);
-
-    int offset = 0;
-    int readLength() {
-      int length = header.getUint32(offset, Endianness.LITTLE_ENDIAN);
-      offset += 4;
-      return length;
-    }
-    List<int> readTable(int length) {
-      var view = new Uint8List.view(bytes.buffer, offset, length);
-      offset += length;
-      return view;
-    }
-
-    Map<int, int> stringOffsetToIndex = {};
-    List<String> buildStringDecodingTable(List<int> data) {
-      List<String> strings = [];
-      int start = 0;
-      while (start < data.length) {
-        stringOffsetToIndex[start] = strings.length;
-
-        int end = start;
-        while (data[end] != 0) end++;
-
-        strings.add(UTF8.decode(data.sublist(start, end)));
-        start = end + 1;
-      }
-      return strings;
-    }
-
-    List<int> decodeSelectors(List<int> data) {
-      assert(data.length % 3 == 0);
-      List<int> indices = new List(data.length ~/ 3);
-      for (int offset = 0; offset < data.length; offset += 3) {
-        int number =
-            data[offset] | (data[offset + 1] << 8) | (data[offset + 2] << 16);
-        if (number == _INVALID_INDEX) number = -1;
-        if (number != -1) number = stringOffsetToIndex[number];
-        indices[offset ~/ 3] = number;
-      }
-      return indices;
-    }
-
-    Map<int, int> decodeTable(List<int> data) {
-      assert(data.length % 6 == 0);
-      Map<int, int> offset2stringId = {};
-      for (int offset = 0; offset < data.length; offset += 6) {
-        int programOffset =
-            data[offset] |
-            (data[offset + 1] << 8) |
-            (data[offset + 2] << 16);
-        int stringOffset =
-            data[offset + 3] |
-            (data[offset + 4] << 8) |
-            (data[offset + 5] << 16);
-
-        if (programOffset != _INVALID_INDEX && stringOffset != _INVALID_INDEX) {
-          offset2stringId[programOffset] = stringOffsetToIndex[stringOffset];
-        } else {
-          offset2stringId[programOffset] = -1;
-        }
-      }
-      return offset2stringId;
-    }
-
-    int stringTableLength = readLength();
-    int selectorTableLength = readLength();
-
-    Map<Configuration, int> classTableLengths = {};
-    Configuration.values.forEach(
-        (conf) => classTableLengths[conf] = readLength());
-
-    Map<Configuration, int> functionTableLengths = {};
-    Configuration.values.forEach(
-        (conf) => functionTableLengths[conf] = readLength());
-
-    List<int> stringTable = readTable(stringTableLength);
-
-    List<String> strings = buildStringDecodingTable(stringTable);
-    List<int> selectorTable = decodeSelectors(readTable(selectorTableLength));
-
-    Map<Configuration, Map<int, int>> classNames = {};
-    Configuration.values.forEach((conf) {
-      classNames[conf] = decodeTable(readTable(classTableLengths[conf]));
-    });
-
-    Map<Configuration, Map<int, int>> functionNames = {};
-    Configuration.values.forEach((conf) {
-      functionNames[conf] = decodeTable(readTable(functionTableLengths[conf]));
-    });
-
-    assert(offset == (_HEADER_LENGTH +
-                      stringTableLength +
-                      selectorTableLength +
-                      classTableLengths.values.fold(0, (a, b) => a + b) +
-                      functionTableLengths.values.fold(0, (a, b) => a + b)));
-
-    return new ProgramInfo(
-        strings,
-        selectorTable,
-        classNames,
-        functionNames,
-        0);  // hashtag for shapshot is not supported for binary format.
-  }
-}
-
-ProgramInfo buildProgramInfo(FletchSystem system, WriteSnapshotResult result) {
-  List<String> strings = [];
-  Map<String, int> stringIndices = {};
-  List<int> selectors = [];
-
-  int newName(String name) {
-    if (name == null) return -1;
-
-    var index = stringIndices[name];
-    if (index == null) {
-      index = strings.length;
-      strings.add(name);
-      stringIndices[name] = index;
-    }
-    return index;
-  }
-
-  void setIndex(List<int> list, int index, value) {
-    while (list.length <= index) {
-      list.add(-1);
-    }
-    list[index] = value;
-  }
-
-  system.symbolByFletchSelectorId.forEach((Pair<int, String> pair) {
-    setIndex(selectors, pair.fst, newName(pair.snd));
-  });
-
-  Map<int, FletchClass> functionId2Class = {};
-  system.classesById.forEach((Pair<int, FletchClass> pair) {
-    FletchClass klass = pair.snd;
-    klass.methodTable.forEach((Pair<int, int> pair) {
-      int functionId = pair.snd;
-      functionId2Class[functionId] = klass;
-    });
-  });
-
-  Map<Configuration, Map<int, int>> newTable() {
-    return <Configuration, Map<int, int>>{
-      Configuration.Offset64BitsDouble : <int,int>{},
-      Configuration.Offset64BitsFloat : <int,int>{},
-      Configuration.Offset32BitsDouble : <int,int>{},
-      Configuration.Offset32BitsFloat : <int,int>{},
-    };
-  }
-
-  fillTable(Map<Configuration, Map<int, int>> dst,
-            Int32List list,
-            String symbol(int id)) {
-    for (int offset = 0; offset < list.length; offset += 5) {
-      int id = list[offset + 0];
-      int stringId = newName(symbol(id));
-
-      if (stringId != -1) {
-        dst[Configuration.Offset64BitsDouble][list[offset + 1]] = stringId;
-        dst[Configuration.Offset64BitsFloat][list[offset + 2]] = stringId;
-        dst[Configuration.Offset32BitsDouble][list[offset + 3]] = stringId;
-        dst[Configuration.Offset32BitsFloat][list[offset + 4]] = stringId;
-      }
-    }
-  }
-
-  var functionNames = newTable();
-  var classNames = newTable();
-
-  fillTable(functionNames,
-            result.functionOffsetTable,
-            (id) => system.functionsById[id].name);
-  fillTable(classNames,
-            result.classOffsetTable,
-            (id) {
-    FletchClass klass = system.classesById[id];
-    if (klass == null) {
-      // Why do we get here?
-      return null;
-    }
-    return klass.name;
-  });
-  fillTable(classNames,
-            result.functionOffsetTable,
-            (id) {
-    FletchClass klass = functionId2Class[id];
-    if (klass != null) return klass.name;
-    return null;
-  });
-
-  return new ProgramInfo(strings, selectors, classNames,
-                         functionNames, result.hashtag);
-}
-
-final RegExp _FrameRegexp =
-    new RegExp(r'^Frame +([0-9]+): Function\(([0-9]+)\)$');
-
-final RegExp _NSMRegexp =
-    new RegExp(r'^NoSuchMethodError\(([0-9]+), ([0-9]+)\)$');
-
-Stream<String> decodeStackFrames(Configuration conf,
-                                 ProgramInfo info,
-                                 Stream<String> input) async* {
-  await for (String line in input) {
-    Match frameMatch = _FrameRegexp.firstMatch(line);
-    Match nsmMatch = _NSMRegexp.firstMatch(line);
-    if (frameMatch != null) {
-      String frameNr = frameMatch.group(1);
-      int functionOffset = int.parse(frameMatch.group(2));
-
-      String className = info.classNameOfFunction(conf, functionOffset);
-      String functionName = info.functionName(conf, functionOffset);
-
-      if (className == null) {
-        yield '   $frameNr: $functionName\n';
-      } else {
-        yield '   $frameNr: $className.$functionName\n';
-      }
-    } else if (nsmMatch != null) {
-      int classOffset = int.parse(nsmMatch.group(1));
-      FletchSelector selector =
-          new FletchSelector(int.parse(nsmMatch.group(2)));
-      String functionName = info.selectorName(selector);
-      String className = info.className(conf, classOffset);
-
-      if (className != null && functionName != null) {
-        yield 'NoSuchMethodError: $className.$functionName\n';
-      } else if (functionName != null) {
-        yield 'NoSuchMethodError: $functionName\n';
-      } else {
-        yield 'NoSuchMethodError: <unknown method>\n';
-      }
-    } else {
-      yield '$line\n';
-    }
-  }
-}
-
-Future<int> decodeProgramMain(
-    List<String> arguments,
-    Stream<List<int>> input,
-    StreamSink<List<int>> output) async {
-
-  usage(message) {
-    print("Invalid arguments: $message");
-    print("Usage: ${io.Platform.script} "
-          "<32/64> <float/double> <snapshot.info.{json/bin}>");
-  }
-
-  if (arguments.length != 3) {
-    usage("Exactly 3 arguments must be supplied");
-    return 1;
-  }
-
-  String bits = arguments[0];
-  if (!['32', '64'].contains(bits)) {
-    usage("Bit width must be 32 or 64.");
-    return 1;
-  }
-
-  String floatOrDouble = arguments[1];
-  if (!['float', 'double'].contains(floatOrDouble)) {
-    usage("Floating point argument must be 'float' or 'double'.");
-    return 1;
-  }
-
-  String filename = arguments[2];
-  bool isJsonFile = filename.endsWith('.json');
-  bool isBinFile = filename.endsWith('.bin');
-  if (!isJsonFile && !isBinFile) {
-    usage("The program info file must end in '.bin' or '.json' "
-          "(was: '$filename').");
-    return 1;
-  }
-
-  io.File file = new io.File(filename);
-  if (!await file.exists()) {
-    usage("The file '$filename' does not exist.");
-    return 1;
-  }
-
-  ProgramInfo info;
-
-  if (isJsonFile) {
-    info = ProgramInfoJson.decode(await file.readAsString());
-  } else {
-    info = ProgramInfoBinary.decode(await file.readAsBytes());
-  }
-
-  Stream<String> inputLines =
-      input.transform(UTF8.decoder).transform(new LineSplitter());
-
-  Configuration conf = _getConfiguration(bits, floatOrDouble);
-  Stream<String> decodedFrames = decodeStackFrames(conf, info, inputLines);
-  await decodedFrames.transform(UTF8.encoder).pipe(output);
-
-  return 0;
-}
-
-
-// We are only interested in two kind of lines in the fletch.ticks file.
-final RegExp tickRegexp =
-    new RegExp(r'^0x([0-9a-f]+),0x([0-9a-f]+),0x([0-9a-f]+)');
-final RegExp propertyRegexp = new RegExp(r'^(\w+)=(.*$)');
-
-// Tick contains information from a line matching tickRegexp.
-class Tick {
-  final int pc;  // The actual program counter where the tick occurred.
-  final int bcp;  // The bytecode pointer relative to program heap start.
-  final int hashtag;
-  Tick(this.pc, this.bcp,this.hashtag);
-}
-
-// Property contains information from a line matching propertyRegexp.
-class Property {
-  final String name;
-  final String value;
-  Property(this.name, this.value);
-}
-
-// FunctionInfo captures profiler information for a function.
-class FunctionInfo {
-  int ticks = 0;  // Accumulated number of ticks.
-  final String name;  // Name that indentifies the function.
-
-  FunctionInfo(this.name);
-
-  int Percent(int total_ticks) => ticks * 100 ~/ total_ticks;
-  
-  void Print(int total_ticks) {
-    print(" -${Percent(total_ticks).toString().padLeft(3, ' ')}% $name");
-  }
-
-  static String ComputeName(String function_name, String class_name) {
-    if (class_name == null) return function_name;
-    return "$class_name.$function_name";
-  }
-}
-
-Stream decode(Stream<List<int>> input) async* {
-  Stream<String> inputLines =
-      input.transform(UTF8.decoder).transform(new LineSplitter());
-  await for (String line in inputLines) {
-    Match t = tickRegexp.firstMatch(line);
-    if (t != null) {
-      int pc = int.parse(t.group(1), radix: 16);
-      int offset = 0;
-      int hashtag = 0;
-      if (t.groupCount > 1) {
-        offset = int.parse(t.group(2), radix: 16);
-        hashtag = int.parse(t.group(3), radix: 16);
-      } 
-      yield new Tick(pc, offset, hashtag);
-    } else {
-      t = propertyRegexp.firstMatch(line);
-      if (t != null) yield new Property(t.group(1), t.group(2));
-    }
-  }
-}
-
-// Binary search for named entry start.
-NamedEntry findEntry(List<NamedEntry> functions, Tick t) {
-  int low = 0;
-  int high = functions.length - 1;
-  while (low + 1 < high) {
-    int i = low + ((high - low) ~/ 2);
-    NamedEntry current = functions[i];
-    if (current.offset < t.bcp) {
-      low = i;
-    } else {
-      high = i;
-    }
-  }
-  return functions[low];
-}
-
-// NamedEntry captures a named entry caputred in the .info.json file.
-class NamedEntry {
-  final int offset;
-  final String name;
-  NamedEntry(this.offset, this.name);
-}
-
-class Profile {
-  final String sample_filename;
-  final String info_filename;
-  Profile(this.sample_filename,this.info_filename);
-
-  // Tick information.
-  int total_ticks = 0;
-  int runtime_ticks = 0;
-  int interpreter_ticks = 0;
-  int discarded_ticks = 0;
-  int other_snapshot_ticks = 0;
-
-  // Memory model.
-  String model;
-
-  // All the ticks.
-  List<Tick> ticks = <Tick>[];
-
-  // The resulting histogram.
-  List<FunctionInfo> histogram;
-
-  void Print() {
-    print("# Tick based profiler result.");
-  
-    for (FunctionInfo func in histogram) {
-      if (func.Percent(total_ticks) < 2) break;
-      func.Print(total_ticks);
-    }
-    
-    print("# ticks in interpreter=${interpreter_ticks}");
-    if (runtime_ticks > 0) print("  runtime=${runtime_ticks}");
-    if (discarded_ticks > 0) print("  discarded=${discarded_ticks}");
-    if (other_snapshot_ticks> 0) {
-      print("  other_snapshot=${other_snapshot_ticks}");
-    }
-  }
-}
-
-Future<Profile> decodeTickSamples(
-    List<String> arguments,
-    Stream<List<int>> input,
-    StreamSink<List<int>> output) async {
-
-  usage(message) {
-    print("Invalid arguments: $message");
-    print("Usage: ${io.Platform.script} <fletch.ticks> <snapshot.info.json>");
-  }
-
-  if (arguments.length != 2) {
-    usage("Exactly 2 arguments must be supplied");
-    return null;
-  }
-
-  String sample_filename = arguments[0];
-  io.File sample_file = new io.File(sample_filename);
-  if (!await sample_file.exists()) {
-    usage("The file '$sample_filename' does not exist.");
-    return null;
-  }
-   
-  String info_filename = arguments[1];
-  if (!info_filename.endsWith('.info.json')) {
-    usage("The program info file must end in '.info.json' "
-          "(was: '$info_filename').");
-    return null;
-  }
-
-  io.File info_file = new io.File(info_filename);
-  if (!await info_file.exists()) {
-    usage("The file '$info_filename' does not exist.");
-    return null;
-  }
-
-  ProgramInfo info = ProgramInfoJson.decode(await info_file.readAsString());
-  Profile profile = new Profile(sample_filename, info_filename);
-
-  // Process the tick sample file.
-  await for (var t in decode(sample_file.openRead())) {
-    if (t is Tick) {
-      profile.ticks.add(t);
-    } else if (t is Property) {
-      if (t.name == 'discarded') profile.discarded_ticks = int.parse(t.value);
-      if (t.name == 'model') profile.model = t.value;
-    }
-  }
-  if (profile.model == null) {
-    print("Memory model absent in sample file.");
-    return null;
-  }
-
-  // Compute the configuration key based on the memory model.
-  Configuration conf;
-  String model = profile.model;
-  if (model == 'b64double') {
-    conf = Configuration.Offset64BitsDouble;
-  } else if (model == 'b64float') {
-    conf = Configuration.Offset64BitsFloat;  
-  } else if (model == 'b32double') {
-    conf = Configuration.Offset32BitsDouble;
-  } else if (model == 'b32float') {
-    conf = Configuration.Offset32BitsFloat;
-  } else {
-    print("Memory model in sample file ${model} cannot be recognized.");
-    return null;
-  }
-
-  // Compute a offset sorted list of Function entries.
-  List<NamedEntry> functions = new List<NamedEntry>();
-  Map<int,int> fnames = info._functionNames[conf];
-  fnames.forEach((key, value) {
-     functions.add(new NamedEntry(key, info._getString(value)));
-  });
-  functions.sort((a, b) => a.offset - b.offset);
-
-  // Compute a offset sorted list of Class entries.
-  List<NamedEntry> classes = new List<NamedEntry>();
-  Map<int,int> cnames = info._classNames[conf];
-  cnames.forEach((key, value) {
-     classes.add(new NamedEntry(key, info._getString(value)));
-  });
-  classes.sort((a, b) => a.offset - b.offset);
-  
-  Map<String,FunctionInfo> results = <String,FunctionInfo>{};
-  for (Tick t in profile.ticks) {
-    profile.total_ticks++;
-    if (t.bcp == 0) {
-      profile.runtime_ticks++;
-    } else if (t.hashtag != info.hashtag) {
-      profile.other_snapshot_ticks++;
-    } else {
-      profile.interpreter_ticks++;
-      NamedEntry fe = findEntry(functions, t);
-      if (fe?.name != null) {
-        NamedEntry ce = findEntry(classes, t);
-        String key = FunctionInfo.ComputeName(fe.name, ce?.name);
-        FunctionInfo f =
-            results.putIfAbsent(key, () => new FunctionInfo(key));
-        f.ticks++;
-      }
-    }
-  }
-
-  // Sort the values into the histogram.
-  List<FunctionInfo> histogram =
-    new List<FunctionInfo>.from(results.values);
-  histogram.sort((a,b) { return b.ticks - a.ticks; });
-  profile.histogram = histogram;
-
-  return profile;
-}
-
-Configuration _getConfiguration(bits, floatOrDouble) {
-  if (bits == '64') {
-    if (floatOrDouble == 'float') return Configuration.Offset64BitsFloat;
-    else if (floatOrDouble == 'double') return Configuration.Offset64BitsDouble;
-  } else if (bits == '32') {
-    if (floatOrDouble == 'float') return Configuration.Offset32BitsFloat;
-    else if (floatOrDouble == 'double') return Configuration.Offset32BitsDouble;
-  }
-  throw 'Invalid arguments';
-}