1 files changed, 61 insertions, 0 deletions
diff --git a/js/src/vm/RegExpStatics.cpp b/js/src/vm/RegExpStatics.cpp
new file mode 100644
index 0000000000..5eef2ffb38
--- /dev/null
+++ b/js/src/vm/RegExpStatics.cpp
@@ -0,0 +1,61 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "vm/RegExpStatics.h"
+
+#include "gc/Zone.h"
+#include "vm/RegExpShared.h"
+
+using namespace js;
+
+// static
+UniquePtr<RegExpStatics> RegExpStatics::create(JSContext* cx) {
+  return cx->make_unique<RegExpStatics>();
+}
+
+bool RegExpStatics::executeLazy(JSContext* cx) {
+  if (!pendingLazyEvaluation) {
+    return true;
+  }
+
+  MOZ_ASSERT(lazySource);
+  MOZ_ASSERT(matchesInput);
+  MOZ_ASSERT(lazyIndex != size_t(-1));
+
+  /* Retrieve or create the RegExpShared in this zone. */
+  Rooted<JSAtom*> source(cx, lazySource);
+  RootedRegExpShared shared(cx,
+                            cx->zone()->regExps().get(cx, source, lazyFlags));
+  if (!shared) {
+    return false;
+  }
+
+  /*
+   * It is not necessary to call aboutToWrite(): evaluation of
+   * implicit copies is safe.
+   */
+
+  /* Execute the full regular expression. */
+  Rooted<JSLinearString*> input(cx, matchesInput);
+  RegExpRunStatus status =
+      RegExpShared::execute(cx, &shared, input, lazyIndex, &this->matches);
+  if (status == RegExpRunStatus::Error) {
+    return false;
+  }
+
+  /*
+   * RegExpStatics are only updated on successful (matching) execution.
+   * Re-running the same expression must therefore produce a matching result.
+   */
+  MOZ_ASSERT(status == RegExpRunStatus::Success);
+
+  /* Unset lazy state and remove rooted values that now have no use. */
+  pendingLazyEvaluation = false;
+  lazySource = nullptr;
+  lazyIndex = size_t(-1);
+
+  return true;
+}