1 files changed, 135 insertions, 0 deletions
diff --git a/deps/v8/src/snapshot/static-roots-gen.cc b/deps/v8/src/snapshot/static-roots-gen.cc
new file mode 100644
index 0000000000..33614c6401
--- /dev/null
+++ b/deps/v8/src/snapshot/static-roots-gen.cc
@@ -0,0 +1,135 @@
+// Copyright 2018 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.
+
+#include "src/snapshot/static-roots-gen.h"
+
+#include <fstream>
+
+#include "src/common/globals.h"
+#include "src/common/ptr-compr-inl.h"
+#include "src/execution/isolate.h"
+#include "src/objects/instance-type-inl.h"
+#include "src/objects/instance-type.h"
+#include "src/objects/objects-definitions.h"
+#include "src/objects/visitors.h"
+#include "src/roots/roots-inl.h"
+#include "src/roots/roots.h"
+
+namespace v8 {
+namespace internal {
+
+class StaticRootsTableGenImpl {
+ public:
+  explicit StaticRootsTableGenImpl(Isolate* isolate) {
+    // Collect all roots
+    ReadOnlyRoots ro_roots(isolate);
+    {
+      RootIndex pos = RootIndex::kFirstReadOnlyRoot;
+#define ADD_ROOT(_, value, CamelName)                       \
+  {                                                         \
+    Tagged_t ptr = V8HeapCompressionScheme::CompressObject( \
+        ro_roots.unchecked_##value().ptr());                \
+    sorted_roots_[ptr].push_back(pos);                      \
+    camel_names_[RootIndex::k##CamelName] = #CamelName;     \
+    ++pos;                                                  \
+  }
+      READ_ONLY_ROOT_LIST(ADD_ROOT)
+#undef ADD_ROOT
+    }
+  }
+
+  const std::map<Tagged_t, std::list<RootIndex>>& sorted_roots() {
+    return sorted_roots_;
+  }
+
+  const std::string& camel_name(RootIndex idx) { return camel_names_.at(idx); }
+
+ private:
+  std::map<Tagged_t, std::list<RootIndex>> sorted_roots_;
+  std::unordered_map<RootIndex, std::string> camel_names_;
+};
+
+void StaticRootsTableGen::write(Isolate* isolate, const char* file) {
+  CHECK_WITH_MSG(!V8_STATIC_ROOTS_BOOL,
+                 "Re-generating the table of roots is only supported in builds "
+                 "with v8_enable_static_roots disabled");
+  CHECK(file);
+  static_assert(static_cast<int>(RootIndex::kFirstReadOnlyRoot) == 0);
+
+  std::ofstream out(file, std::ios::binary);
+
+  out << "// Copyright 2022 the V8 project authors. All rights reserved.\n"
+      << "// Use of this source code is governed by a BSD-style license "
+         "that can be\n"
+      << "// found in the LICENSE file.\n"
+      << "\n"
+      << "// This file is automatically generated by "
+         "`tools/dev/gen-static-roots.py`. Do\n// not edit manually.\n"
+      << "\n"
+      << "#ifndef V8_ROOTS_STATIC_ROOTS_H_\n"
+      << "#define V8_ROOTS_STATIC_ROOTS_H_\n"
+      << "\n"
+      << "#include \"src/common/globals.h\"\n"
+      << "\n"
+      << "#if V8_STATIC_ROOTS_BOOL\n"
+      << "\n"
+      << "#include \"src/objects/instance-type.h\"\n"
+      << "#include \"src/roots/roots.h\"\n"
+      << "\n"
+      << "// Disabling Wasm or Intl invalidates the contents of "
+         "static-roots.h.\n"
+      << "// TODO(olivf): To support static roots for multiple build "
+         "configurations we\n"
+      << "//              will need to generate target specific versions of "
+         "this file.\n"
+      << "static_assert(V8_ENABLE_WEBASSEMBLY);\n"
+      << "static_assert(V8_INTL_SUPPORT);\n"
+      << "\n"
+      << "namespace v8 {\n"
+      << "namespace internal {\n"
+      << "\n"
+      << "struct StaticReadOnlyRoot {\n";
+
+  // Output a symbol for every root. Ordered by ptr to make it easier to see the
+  // memory layout of the read only page.
+  const auto size = static_cast<int>(RootIndex::kReadOnlyRootsCount);
+  StaticRootsTableGenImpl gen(isolate);
+
+  for (auto& entry : gen.sorted_roots()) {
+    Tagged_t ptr = entry.first;
+    const std::list<RootIndex>& roots = entry.second;
+
+    for (RootIndex root : roots) {
+      static const char* kPreString = "  static constexpr Tagged_t k";
+      const std::string& name = gen.camel_name(root);
+      size_t ptr_len = ceil(log2(ptr) / 4.0);
+      // Full line is: "kPreString|name = 0x.....;"
+      size_t len = strlen(kPreString) + name.length() + 5 + ptr_len + 1;
+      out << kPreString << name << " =";
+      if (len > 80) out << "\n     ";
+      out << " 0x" << std::hex << ptr << std::dec << ";\n";
+    }
+  }
+  out << "};\n";
+
+  // Output in order of roots table
+  out << "\nstatic constexpr std::array<Tagged_t, " << size
+      << "> StaticReadOnlyRootsPointerTable = {\n";
+
+  {
+#define ENTRY(_1, _2, CamelName) \
+  out << "    StaticReadOnlyRoot::k" << #CamelName << ",\n";
+    READ_ONLY_ROOT_LIST(ENTRY)
+#undef ENTRY
+    out << "};\n";
+  }
+  out << "\n"
+      << "}  // namespace internal\n"
+      << "}  // namespace v8\n"
+      << "#endif  // V8_STATIC_ROOTS_BOOL\n"
+      << "#endif  // V8_ROOTS_STATIC_ROOTS_H_\n";
+}
+
+}  // namespace internal
+}  // namespace v8