1 files changed, 100 insertions, 0 deletions
diff --git a/js/src/jsapi-tests/testPreserveJitCode.cpp b/js/src/jsapi-tests/testPreserveJitCode.cpp
new file mode 100644
index 0000000000..e27e63f2d1
--- /dev/null
+++ b/js/src/jsapi-tests/testPreserveJitCode.cpp
@@ -0,0 +1,100 @@
+/* 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 "mozilla/Utf8.h"  // mozilla::Utf8Unit
+
+#include "jit/Ion.h"                      // js::jit::IsIonEnabled
+#include "js/CallAndConstruct.h"          // JS::CallFunction
+#include "js/CompilationAndEvaluation.h"  // JS::CompileFunction
+#include "js/GlobalObject.h"              // JS_NewGlobalObject
+#include "js/SourceText.h"                // JS::Source{Ownership,Text}
+#include "jsapi-tests/tests.h"
+#include "util/Text.h"
+
+#include "vm/JSObject-inl.h"
+#include "vm/JSScript-inl.h"
+
+using namespace JS;
+
+static void ScriptCallback(JSRuntime* rt, void* data, js::BaseScript* script,
+                           const JS::AutoRequireNoGC& nogc) {
+  unsigned& count = *static_cast<unsigned*>(data);
+  if (script->asJSScript()->hasIonScript()) {
+    ++count;
+  }
+}
+
+BEGIN_TEST(test_PreserveJitCode) {
+  CHECK(testPreserveJitCode(false, 0));
+  CHECK(testPreserveJitCode(true, 1));
+  return true;
+}
+
+unsigned countIonScripts(JSObject* global) {
+  unsigned count = 0;
+  js::IterateScripts(cx, global->nonCCWRealm(), &count, ScriptCallback);
+  return count;
+}
+
+bool testPreserveJitCode(bool preserveJitCode, unsigned remainingIonScripts) {
+  cx->runtime()->setOffthreadIonCompilationEnabled(false);
+
+  RootedObject global(cx, createTestGlobal(preserveJitCode));
+  CHECK(global);
+  JSAutoRealm ar(cx, global);
+
+  // The Ion JIT may be unavailable due to --disable-jit or lack of support
+  // for this platform.
+  if (!js::jit::IsIonEnabled(cx)) {
+    knownFail = true;
+  }
+
+  CHECK_EQUAL(countIonScripts(global), 0u);
+
+  static constexpr char source[] =
+      "var i = 0;\n"
+      "var sum = 0;\n"
+      "while (i < 10) {\n"
+      "    sum += i;\n"
+      "    ++i;\n"
+      "}\n"
+      "return sum;\n";
+  constexpr unsigned length = js_strlen(source);
+
+  JS::SourceText<mozilla::Utf8Unit> srcBuf;
+  CHECK(srcBuf.init(cx, source, length, JS::SourceOwnership::Borrowed));
+
+  JS::CompileOptions options(cx);
+  options.setFileAndLine(__FILE__, 1);
+
+  JS::RootedFunction fun(cx);
+  JS::RootedObjectVector emptyScopeChain(cx);
+  fun = JS::CompileFunction(cx, emptyScopeChain, options, "f", 0, nullptr,
+                            srcBuf);
+  CHECK(fun);
+
+  RootedValue value(cx);
+  for (unsigned i = 0; i < 1500; ++i) {
+    CHECK(JS_CallFunction(cx, global, fun, JS::HandleValueArray::empty(),
+                          &value));
+  }
+  CHECK_EQUAL(value.toInt32(), 45);
+  CHECK_EQUAL(countIonScripts(global), 1u);
+
+  NonIncrementalGC(cx, JS::GCOptions::Normal, GCReason::API);
+  CHECK_EQUAL(countIonScripts(global), remainingIonScripts);
+
+  NonIncrementalGC(cx, JS::GCOptions::Shrink, GCReason::API);
+  CHECK_EQUAL(countIonScripts(global), 0u);
+
+  return true;
+}
+
+JSObject* createTestGlobal(bool preserveJitCode) {
+  JS::RealmOptions options;
+  options.creationOptions().setPreserveJitCode(preserveJitCode);
+  return JS_NewGlobalObject(cx, getGlobalClass(), nullptr,
+                            JS::FireOnNewGlobalHook, options);
+}
+END_TEST(test_PreserveJitCode)