1 files changed, 93 insertions, 0 deletions
diff --git a/js/src/vm/UbiNodeShortestPaths.cpp b/js/src/vm/UbiNodeShortestPaths.cpp
new file mode 100644
index 000000000..a1a293997
--- /dev/null
+++ b/js/src/vm/UbiNodeShortestPaths.cpp
@@ -0,0 +1,93 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * 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 "js/UbiNodeShortestPaths.h"
+
+#include "mozilla/Maybe.h"
+#include "mozilla/Move.h"
+
+#include "jsstr.h"
+
+namespace JS {
+namespace ubi {
+
+JS_PUBLIC_API(BackEdge::Ptr)
+BackEdge::clone() const
+{
+    BackEdge::Ptr clone(js_new<BackEdge>());
+    if (!clone)
+        return nullptr;
+
+    clone->predecessor_ = predecessor();
+    if (name()) {
+        clone->name_ = js::DuplicateString(name().get());
+        if (!clone->name_)
+            return nullptr;
+    }
+    return mozilla::Move(clone);
+}
+
+#ifdef DEBUG
+
+static void
+dumpNode(const JS::ubi::Node& node)
+{
+    fprintf(stderr, "    %p ", (void*) node.identifier());
+    js_fputs(node.typeName(), stderr);
+    if (node.coarseType() == JS::ubi::CoarseType::Object) {
+        if (const char* clsName = node.jsObjectClassName())
+            fprintf(stderr, " [object %s]", clsName);
+    }
+    fputc('\n', stderr);
+}
+
+JS_PUBLIC_API(void)
+dumpPaths(JSContext* cx, Node node, uint32_t maxNumPaths /* = 10 */)
+{
+    mozilla::Maybe<AutoCheckCannotGC> nogc;
+
+    JS::ubi::RootList rootList(cx, nogc, true);
+    MOZ_ASSERT(rootList.init());
+
+    NodeSet targets;
+    bool ok = targets.init() && targets.putNew(node);
+    MOZ_ASSERT(ok);
+
+    auto paths = ShortestPaths::Create(cx, nogc.ref(), maxNumPaths, &rootList, mozilla::Move(targets));
+    MOZ_ASSERT(paths.isSome());
+
+    int i = 0;
+    ok = paths->forEachPath(node, [&](Path& path) {
+        fprintf(stderr, "Path %d:\n", i++);
+        for (auto backEdge : path) {
+            dumpNode(backEdge->predecessor());
+            fprintf(stderr, "            |\n");
+            fprintf(stderr, "            |\n");
+            fprintf(stderr, "        '");
+
+            const char16_t* name = backEdge->name().get();
+            if (!name)
+                name = u"<no edge name>";
+            js_fputs(name, stderr);
+            fprintf(stderr, "'\n");
+
+            fprintf(stderr, "            |\n");
+            fprintf(stderr, "            V\n");
+        }
+
+        dumpNode(node);
+        fputc('\n', stderr);
+        return true;
+    });
+    MOZ_ASSERT(ok);
+
+    if (i == 0)
+        fprintf(stderr, "No retaining paths found.\n");
+}
+#endif
+
+} // namespace ubi
+} // namespace JS