1 files changed, 117 insertions, 0 deletions
diff --git a/js/src/jsapi-tests/testGCStoreBufferRemoval.cpp b/js/src/jsapi-tests/testGCStoreBufferRemoval.cpp
new file mode 100644
index 0000000000..81bf9356b5
--- /dev/null
+++ b/js/src/jsapi-tests/testGCStoreBufferRemoval.cpp
@@ -0,0 +1,117 @@
+/* -*- 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 "gc/Barrier.h"
+#include "jsapi-tests/tests.h"
+
+using namespace JS;
+using namespace js;
+
+struct AutoIgnoreRootingHazards {
+  // Force a nontrivial destructor so the compiler sees the whole RAII scope
+  static volatile int depth;
+  AutoIgnoreRootingHazards() { depth++; }
+  ~AutoIgnoreRootingHazards() { depth--; }
+} JS_HAZ_GC_SUPPRESSED;
+volatile int AutoIgnoreRootingHazards::depth = 0;
+
+BEGIN_TEST(testGCStoreBufferRemoval) {
+  // Sanity check - objects start in the nursery and then become tenured.
+  JS_GC(cx);
+  JS::RootedObject obj(cx, NurseryObject());
+  CHECK(js::gc::IsInsideNursery(obj.get()));
+  JS_GC(cx);
+  CHECK(!js::gc::IsInsideNursery(obj.get()));
+  JS::RootedObject tenuredObject(cx, obj);
+
+  // Hide the horrors herein from the static rooting analysis.
+  AutoIgnoreRootingHazards ignore;
+
+  // Test removal of store buffer entries added by HeapPtr<T>.
+  {
+    JSObject* badObject = reinterpret_cast<JSObject*>(1);
+    JSObject* punnedPtr = nullptr;
+    HeapPtr<JSObject*>* relocPtr =
+        reinterpret_cast<HeapPtr<JSObject*>*>(&punnedPtr);
+    new (relocPtr) HeapPtr<JSObject*>;
+    *relocPtr = NurseryObject();
+    relocPtr->~HeapPtr<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+
+    new (relocPtr) HeapPtr<JSObject*>;
+    *relocPtr = NurseryObject();
+    *relocPtr = tenuredObject;
+    relocPtr->~HeapPtr<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+
+    new (relocPtr) HeapPtr<JSObject*>;
+    *relocPtr = NurseryObject();
+    *relocPtr = nullptr;
+    relocPtr->~HeapPtr<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+  }
+
+  // Test removal of store buffer entries added by HeapPtr<Value>.
+  {
+    Value punnedValue;
+    HeapPtr<Value>* relocValue =
+        reinterpret_cast<HeapPtr<Value>*>(&punnedValue);
+    new (relocValue) HeapPtr<Value>;
+    *relocValue = ObjectValue(*NurseryObject());
+    relocValue->~HeapPtr<Value>();
+    punnedValue = js::PoisonedObjectValue(0x48);
+    JS_GC(cx);
+
+    new (relocValue) HeapPtr<Value>;
+    *relocValue = ObjectValue(*NurseryObject());
+    *relocValue = ObjectValue(*tenuredObject);
+    relocValue->~HeapPtr<Value>();
+    punnedValue = js::PoisonedObjectValue(0x48);
+    JS_GC(cx);
+
+    new (relocValue) HeapPtr<Value>;
+    *relocValue = ObjectValue(*NurseryObject());
+    *relocValue = NullValue();
+    relocValue->~HeapPtr<Value>();
+    punnedValue = js::PoisonedObjectValue(0x48);
+    JS_GC(cx);
+  }
+
+  // Test removal of store buffer entries added by Heap<T>.
+  {
+    JSObject* badObject = reinterpret_cast<JSObject*>(1);
+    JSObject* punnedPtr = nullptr;
+    Heap<JSObject*>* heapPtr = reinterpret_cast<Heap<JSObject*>*>(&punnedPtr);
+    new (heapPtr) Heap<JSObject*>;
+    *heapPtr = NurseryObject();
+    heapPtr->~Heap<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+
+    new (heapPtr) Heap<JSObject*>;
+    *heapPtr = NurseryObject();
+    *heapPtr = tenuredObject;
+    heapPtr->~Heap<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+
+    new (heapPtr) Heap<JSObject*>;
+    *heapPtr = NurseryObject();
+    *heapPtr = nullptr;
+    heapPtr->~Heap<JSObject*>();
+    punnedPtr = badObject;
+    JS_GC(cx);
+  }
+
+  return true;
+}
+
+JSObject* NurseryObject() { return JS_NewPlainObject(cx); }
+END_TEST(testGCStoreBufferRemoval)