1 files changed, 63 insertions, 0 deletions
diff --git a/deps/v8/tools/debug_helper/gen-heap-constants.py b/deps/v8/tools/debug_helper/gen-heap-constants.py
new file mode 100644
index 0000000000..0fd575a994
--- /dev/null
+++ b/deps/v8/tools/debug_helper/gen-heap-constants.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python
+# Copyright 2019 the V8 project authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""This program writes a C++ file that can be used to look up whether a given
+address matches known object locations. The first argument is the directory
+containing the file v8heapconst.py; the second argument is the output .cc file.
+"""
+
+import sys
+sys.path.insert(0, sys.argv[1])
+import v8heapconst
+
+out = """
+#include <cstdint>
+#include <string>
+
+namespace v8_debug_helper_internal {
+"""
+
+def iterate_objects(target_space, camel_space_name):
+  global out
+  result = []
+  for (space, offset), (instance_type, name) in v8heapconst.KNOWN_MAPS.items():
+    if space == target_space:
+      result.append((offset, name))
+  for (space, offset), name in v8heapconst.KNOWN_OBJECTS.items():
+    if space == target_space:
+      result.append((offset, name))
+  out = out + '\nstd::string FindKnownObjectIn' + camel_space_name \
+      + '(uintptr_t offset) {\n  switch (offset) {\n'
+  for offset, name in result:
+    out = out + '    case ' + str(offset) + ': return "' + name + '";\n'
+  out = out + '    default: return "";\n  }\n}\n'
+
+iterate_objects('map_space', 'MapSpace')
+iterate_objects('read_only_space', 'ReadOnlySpace')
+iterate_objects('old_space', 'OldSpace')
+
+def iterate_maps(target_space, camel_space_name):
+  global out
+  out = out + '\nint FindKnownMapInstanceTypeIn' + camel_space_name \
+      + '(uintptr_t offset) {\n  switch (offset) {\n'
+  for (space, offset), (instance_type, name) in v8heapconst.KNOWN_MAPS.items():
+    if space == target_space:
+      out = out + '    case ' + str(offset) + ': return ' + str(instance_type) \
+          + ';\n'
+  out = out + '    default: return -1;\n  }\n}\n'
+
+iterate_maps('map_space', 'MapSpace')
+iterate_maps('read_only_space', 'ReadOnlySpace')
+
+out = out + '\n}\n'
+
+try:
+  with open(sys.argv[2], "r") as out_file:
+    if out == out_file.read():
+      sys.exit(0)  # No modification needed.
+except:
+  pass  # File probably doesn't exist; write it.
+with open(sys.argv[2], "w") as out_file:
+  out_file.write(out)