Split nodes and edges into separate arrays in heap snapshot serialization.

test/cctest/test-heap-profiler.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 //
 // Tests for heap profiler
 
 #include "v8.h"
 
 #include "cctest.h"
 #include "heap-profiler.h"
 #include "snapshot.h"
 #include "utils-inl.h"
@@ skipping 595 matching lines @@
   env->Global()->Set(v8_str("json_snapshot"), json_string);
   v8::Local<v8::Value> snapshot_parse_result = CompileRun(
       "var parsed = JSON.parse(json_snapshot); true;");
   CHECK(!snapshot_parse_result.IsEmpty());
 
   // Verify that snapshot object has required fields.
   v8::Local<v8::Object> parsed_snapshot =
       env->Global()->Get(v8_str("parsed"))->ToObject();
   CHECK(parsed_snapshot->Has(v8_str("snapshot")));
   CHECK(parsed_snapshot->Has(v8_str("nodes")));
+  CHECK(parsed_snapshot->Has(v8_str("edges")));
   CHECK(parsed_snapshot->Has(v8_str("strings")));
 
   // Get node and edge "member" offsets.
   v8::Local<v8::Value> meta_analysis_result = CompileRun(
-      "var parsed_meta = parsed.nodes[0];\n"
-      "var children_count_offset ="
-      "    parsed_meta.fields.indexOf('children_count');\n"
-      "var children_offset ="
-      "    parsed_meta.fields.indexOf('children');\n"
-      "var children_meta ="
-      "    parsed_meta.types[children_offset];\n"
-      "var child_fields_count = children_meta.fields.length;\n"
-      "var child_type_offset ="
-      "    children_meta.fields.indexOf('type');\n"
-      "var child_name_offset ="
-      "    children_meta.fields.indexOf('name_or_index');\n"
-      "var child_to_node_offset ="
-      "    children_meta.fields.indexOf('to_node');\n"
+      "var meta = parsed.nodes[0];\n"
+      "var edges_index_offset = meta.node_fields.indexOf('edges_index');\n"
+      "var node_fields_count = meta.node_fields.length;\n"
+      "var edge_fields_count = meta.edge_fields.length;\n"
+      "var edge_type_offset = meta.edge_fields.indexOf('type');\n"
+      "var edge_name_offset = meta.edge_fields.indexOf('name_or_index');\n"
+      "var edge_to_node_offset = meta.edge_fields.indexOf('to_node');\n"
       "var property_type ="
-      "    children_meta.types[child_type_offset].indexOf('property');\n"
+      "    meta.edge_types[edge_type_offset].indexOf('property');\n"
       "var shortcut_type ="
-      "    children_meta.types[child_type_offset].indexOf('shortcut');");
+      "    meta.edge_types[edge_type_offset].indexOf('shortcut');\n"
+      "parsed.nodes = parsed.nodes.slice(1);\n"

[mnaganov (inactive), 2012/04/10 22:28:09]

Why is this needed?

[alexeif, 2012/04/11 12:49:57]

it's not needed anymore. I removed the meta node from nodes array.

+      "parsed.nodes.concat(0, 0, 0, 0, 0, 0, parsed.edges.length);");
   CHECK(!meta_analysis_result.IsEmpty());
 
   // A helper function for processing encoded nodes.
   CompileRun(
       "function GetChildPosByProperty(pos, prop_name, prop_type) {\n"
       "  var nodes = parsed.nodes;\n"
+      "  var edges = parsed.edges;\n"
       "  var strings = parsed.strings;\n"
-      "  for (var i = 0,\n"
-      "      count = nodes[pos + children_count_offset] * child_fields_count;\n"
-      "      i < count; i += child_fields_count) {\n"
-      "    var child_pos = pos + children_offset + i;\n"
-      "    if (nodes[child_pos + child_type_offset] === prop_type\n"
-      "       && strings[nodes[child_pos + child_name_offset]] === prop_name)\n"
-      "        return nodes[child_pos + child_to_node_offset];\n"
+      "  for (var i = nodes[pos + edges_index_offset],\n"
+      "      count = nodes[pos + node_fields_count + edges_index_offset];\n"
+      "      i < count; i += edge_fields_count) {\n"
+      "    if (edges[i + edge_type_offset] === prop_type\n"
+      "        && strings[edges[i + edge_name_offset]] === prop_name)\n"
+      "      return edges[i + edge_to_node_offset];\n"
       "  }\n"
       "  return null;\n"
       "}\n");
   // Get the string index using the path: <root> -> <global>.b.x.s
   v8::Local<v8::Value> string_obj_pos_val = CompileRun(
       "GetChildPosByProperty(\n"
       "  GetChildPosByProperty(\n"
       "    GetChildPosByProperty("
-      "      parsed.nodes[1 + children_offset + child_to_node_offset],"
-      "      \"b\",shortcut_type),\n"
+      "      parsed.edges[parsed.nodes[edges_index_offset]"
+      "                   + edge_to_node_offset],"
+      "      \"b\", shortcut_type),\n"
       "    \"x\", property_type),"
       "  \"s\", property_type)");
   CHECK(!string_obj_pos_val.IsEmpty());
   int string_obj_pos =
       static_cast<int>(string_obj_pos_val->ToNumber()->Value());
   v8::Local<v8::Object> nodes_array =
       parsed_snapshot->Get(v8_str("nodes"))->ToObject();
   int string_index = static_cast<int>(
       nodes_array->Get(string_obj_pos + 1)->ToNumber()->Value());
   CHECK_GT(string_index, 0);
@@ skipping 693 matching lines @@
   // Dipose the persistent handles in a different order.
   p_AAA.Dispose();
   CHECK_EQ(global_handle_count + 2,
            v8::HeapProfiler::GetPersistentHandleCount());
   p_CCC.Dispose();
   CHECK_EQ(global_handle_count + 1,
            v8::HeapProfiler::GetPersistentHandleCount());
   p_BBB.Dispose();
   CHECK_EQ(global_handle_count, v8::HeapProfiler::GetPersistentHandleCount());
 }