1 files changed, 449 insertions, 0 deletions
diff --git a/js/src/debugger/DebuggerMemory.cpp b/js/src/debugger/DebuggerMemory.cpp
new file mode 100644
index 0000000000..43ad1ea18e
--- /dev/null
+++ b/js/src/debugger/DebuggerMemory.cpp
@@ -0,0 +1,449 @@
+/* -*- 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 "debugger/DebuggerMemory.h"
+
+#include "mozilla/Maybe.h"
+#include "mozilla/Vector.h"
+
+#include <stdlib.h>
+#include <utility>
+
+#include "builtin/MapObject.h"
+#include "debugger/Debugger.h"
+#include "gc/Marking.h"
+#include "js/AllocPolicy.h"
+#include "js/Debug.h"
+#include "js/friend/ErrorMessages.h"  // js::GetErrorMessage, JSMSG_*
+#include "js/PropertySpec.h"
+#include "js/TracingAPI.h"
+#include "js/UbiNode.h"
+#include "js/UbiNodeCensus.h"
+#include "js/Utility.h"
+#include "vm/GlobalObject.h"
+#include "vm/JSContext.h"
+#include "vm/PlainObject.h"  // js::PlainObject
+#include "vm/Realm.h"
+#include "vm/SavedStacks.h"
+
+#include "debugger/Debugger-inl.h"
+#include "vm/NativeObject-inl.h"
+
+using namespace js;
+
+using mozilla::Maybe;
+using mozilla::Nothing;
+
+/* static */
+DebuggerMemory* DebuggerMemory::create(JSContext* cx, Debugger* dbg) {
+  Value memoryProtoValue =
+      dbg->object->getReservedSlot(Debugger::JSSLOT_DEBUG_MEMORY_PROTO);
+  RootedObject memoryProto(cx, &memoryProtoValue.toObject());
+  Rooted<DebuggerMemory*> memory(
+      cx, NewObjectWithGivenProto<DebuggerMemory>(cx, memoryProto));
+  if (!memory) {
+    return nullptr;
+  }
+
+  dbg->object->setReservedSlot(Debugger::JSSLOT_DEBUG_MEMORY_INSTANCE,
+                               ObjectValue(*memory));
+  memory->setReservedSlot(JSSLOT_DEBUGGER, ObjectValue(*dbg->object));
+
+  return memory;
+}
+
+Debugger* DebuggerMemory::getDebugger() {
+  const Value& dbgVal = getReservedSlot(JSSLOT_DEBUGGER);
+  return Debugger::fromJSObject(&dbgVal.toObject());
+}
+
+/* static */
+bool DebuggerMemory::construct(JSContext* cx, unsigned argc, Value* vp) {
+  JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_NO_CONSTRUCTOR,
+                            "Debugger.Source");
+  return false;
+}
+
+/* static */ const JSClass DebuggerMemory::class_ = {
+    "Memory", JSCLASS_HAS_PRIVATE | JSCLASS_HAS_RESERVED_SLOTS(JSSLOT_COUNT)};
+
+/* static */
+DebuggerMemory* DebuggerMemory::checkThis(JSContext* cx, CallArgs& args) {
+  const Value& thisValue = args.thisv();
+
+  if (!thisValue.isObject()) {
+    JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+                              JSMSG_OBJECT_REQUIRED,
+                              InformalValueTypeName(thisValue));
+    return nullptr;
+  }
+
+  JSObject& thisObject = thisValue.toObject();
+  if (!thisObject.is<DebuggerMemory>()) {
+    JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+                              JSMSG_INCOMPATIBLE_PROTO, class_.name, "method",
+                              thisObject.getClass()->name);
+    return nullptr;
+  }
+
+  // Check for Debugger.Memory.prototype, which has the same class as
+  // Debugger.Memory instances, however doesn't actually represent an instance
+  // of Debugger.Memory. It is the only object that is<DebuggerMemory>() but
+  // doesn't have a Debugger instance.
+  if (thisObject.as<DebuggerMemory>()
+          .getReservedSlot(JSSLOT_DEBUGGER)
+          .isUndefined()) {
+    JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+                              JSMSG_INCOMPATIBLE_PROTO, class_.name, "method",
+                              "prototype object");
+    return nullptr;
+  }
+
+  return &thisObject.as<DebuggerMemory>();
+}
+
+struct MOZ_STACK_CLASS DebuggerMemory::CallData {
+  JSContext* cx;
+  const CallArgs& args;
+
+  Handle<DebuggerMemory*> memory;
+
+  CallData(JSContext* cx, const CallArgs& args, Handle<DebuggerMemory*> memory)
+      : cx(cx), args(args), memory(memory) {}
+
+  // Accessor properties of Debugger.Memory.prototype.
+
+  bool setTrackingAllocationSites();
+  bool getTrackingAllocationSites();
+  bool setMaxAllocationsLogLength();
+  bool getMaxAllocationsLogLength();
+  bool setAllocationSamplingProbability();
+  bool getAllocationSamplingProbability();
+  bool getAllocationsLogOverflowed();
+  bool getOnGarbageCollection();
+  bool setOnGarbageCollection();
+
+  // Function properties of Debugger.Memory.prototype.
+
+  bool takeCensus();
+  bool drainAllocationsLog();
+
+  using Method = bool (CallData::*)();
+
+  template <Method MyMethod>
+  static bool ToNative(JSContext* cx, unsigned argc, Value* vp);
+};
+
+template <DebuggerMemory::CallData::Method MyMethod>
+/* static */
+bool DebuggerMemory::CallData::ToNative(JSContext* cx, unsigned argc,
+                                        Value* vp) {
+  CallArgs args = CallArgsFromVp(argc, vp);
+
+  Rooted<DebuggerMemory*> memory(cx, DebuggerMemory::checkThis(cx, args));
+  if (!memory) {
+    return false;
+  }
+
+  CallData data(cx, args, memory);
+  return (data.*MyMethod)();
+}
+
+static bool undefined(const CallArgs& args) {
+  args.rval().setUndefined();
+  return true;
+}
+
+bool DebuggerMemory::CallData::setTrackingAllocationSites() {
+  if (!args.requireAtLeast(cx, "(set trackingAllocationSites)", 1)) {
+    return false;
+  }
+
+  Debugger* dbg = memory->getDebugger();
+  bool enabling = ToBoolean(args[0]);
+
+  if (enabling == dbg->trackingAllocationSites) {
+    return undefined(args);
+  }
+
+  dbg->trackingAllocationSites = enabling;
+
+  if (enabling) {
+    if (!dbg->addAllocationsTrackingForAllDebuggees(cx)) {
+      dbg->trackingAllocationSites = false;
+      return false;
+    }
+  } else {
+    dbg->removeAllocationsTrackingForAllDebuggees();
+  }
+
+  return undefined(args);
+}
+
+bool DebuggerMemory::CallData::getTrackingAllocationSites() {
+  args.rval().setBoolean(memory->getDebugger()->trackingAllocationSites);
+  return true;
+}
+
+bool DebuggerMemory::CallData::drainAllocationsLog() {
+  Debugger* dbg = memory->getDebugger();
+
+  if (!dbg->trackingAllocationSites) {
+    JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+                              JSMSG_NOT_TRACKING_ALLOCATIONS,
+                              "drainAllocationsLog");
+    return false;
+  }
+
+  size_t length = dbg->allocationsLog.length();
+
+  RootedArrayObject result(cx, NewDenseFullyAllocatedArray(cx, length));
+  if (!result) {
+    return false;
+  }
+  result->ensureDenseInitializedLength(0, length);
+
+  for (size_t i = 0; i < length; i++) {
+    RootedPlainObject obj(cx, NewBuiltinClassInstance<PlainObject>(cx));
+    if (!obj) {
+      return false;
+    }
+
+    // Don't pop the AllocationsLogEntry yet. The queue's links are followed
+    // by the GC to find the AllocationsLogEntry, but are not barriered, so
+    // we must edit them with great care. Use the queue entry in place, and
+    // then pop and delete together.
+    Debugger::AllocationsLogEntry& entry = dbg->allocationsLog.front();
+
+    RootedValue frame(cx, ObjectOrNullValue(entry.frame));
+    if (!DefineDataProperty(cx, obj, cx->names().frame, frame)) {
+      return false;
+    }
+
+    double when =
+        (entry.when - mozilla::TimeStamp::ProcessCreation()).ToMilliseconds();
+    RootedValue timestampValue(cx, NumberValue(when));
+    if (!DefineDataProperty(cx, obj, cx->names().timestamp, timestampValue)) {
+      return false;
+    }
+
+    RootedString className(
+        cx, Atomize(cx, entry.className, strlen(entry.className)));
+    if (!className) {
+      return false;
+    }
+    RootedValue classNameValue(cx, StringValue(className));
+    if (!DefineDataProperty(cx, obj, cx->names().class_, classNameValue)) {
+      return false;
+    }
+
+    RootedValue size(cx, NumberValue(entry.size));
+    if (!DefineDataProperty(cx, obj, cx->names().size, size)) {
+      return false;
+    }
+
+    RootedValue inNursery(cx, BooleanValue(entry.inNursery));
+    if (!DefineDataProperty(cx, obj, cx->names().inNursery, inNursery)) {
+      return false;
+    }
+
+    result->setDenseElement(i, ObjectValue(*obj));
+
+    // Pop the front queue entry, and delete it immediately, so that the GC
+    // sees the AllocationsLogEntry's HeapPtr barriers run atomically with
+    // the change to the graph (the queue link).
+    dbg->allocationsLog.popFront();
+  }
+
+  dbg->allocationsLogOverflowed = false;
+  args.rval().setObject(*result);
+  return true;
+}
+
+bool DebuggerMemory::CallData::getMaxAllocationsLogLength() {
+  args.rval().setInt32(memory->getDebugger()->maxAllocationsLogLength);
+  return true;
+}
+
+bool DebuggerMemory::CallData::setMaxAllocationsLogLength() {
+  if (!args.requireAtLeast(cx, "(set maxAllocationsLogLength)", 1)) {
+    return false;
+  }
+
+  int32_t max;
+  if (!ToInt32(cx, args[0], &max)) {
+    return false;
+  }
+
+  if (max < 1) {
+    JS_ReportErrorNumberASCII(
+        cx, GetErrorMessage, nullptr, JSMSG_UNEXPECTED_TYPE,
+        "(set maxAllocationsLogLength)'s parameter", "not a positive integer");
+    return false;
+  }
+
+  Debugger* dbg = memory->getDebugger();
+  dbg->maxAllocationsLogLength = max;
+
+  while (dbg->allocationsLog.length() > dbg->maxAllocationsLogLength) {
+    dbg->allocationsLog.popFront();
+  }
+
+  args.rval().setUndefined();
+  return true;
+}
+
+bool DebuggerMemory::CallData::getAllocationSamplingProbability() {
+  args.rval().setDouble(memory->getDebugger()->allocationSamplingProbability);
+  return true;
+}
+
+bool DebuggerMemory::CallData::setAllocationSamplingProbability() {
+  if (!args.requireAtLeast(cx, "(set allocationSamplingProbability)", 1)) {
+    return false;
+  }
+
+  double probability;
+  if (!ToNumber(cx, args[0], &probability)) {
+    return false;
+  }
+
+  // Careful!  This must also reject NaN.
+  if (!(0.0 <= probability && probability <= 1.0)) {
+    JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+                              JSMSG_UNEXPECTED_TYPE,
+                              "(set allocationSamplingProbability)'s parameter",
+                              "not a number between 0 and 1");
+    return false;
+  }
+
+  Debugger* dbg = memory->getDebugger();
+  if (dbg->allocationSamplingProbability != probability) {
+    dbg->allocationSamplingProbability = probability;
+
+    // If this is a change any debuggees would observe, have all debuggee
+    // realms recompute their sampling probabilities.
+    if (dbg->trackingAllocationSites) {
+      for (auto r = dbg->debuggees.all(); !r.empty(); r.popFront()) {
+        r.front()->realm()->chooseAllocationSamplingProbability();
+      }
+    }
+  }
+
+  args.rval().setUndefined();
+  return true;
+}
+
+bool DebuggerMemory::CallData::getAllocationsLogOverflowed() {
+  args.rval().setBoolean(memory->getDebugger()->allocationsLogOverflowed);
+  return true;
+}
+
+bool DebuggerMemory::CallData::getOnGarbageCollection() {
+  return Debugger::getGarbageCollectionHook(cx, args, *memory->getDebugger());
+}
+
+bool DebuggerMemory::CallData::setOnGarbageCollection() {
+  return Debugger::setGarbageCollectionHook(cx, args, *memory->getDebugger());
+}
+
+/* Debugger.Memory.prototype.takeCensus */
+
+JS_PUBLIC_API void JS::dbg::SetDebuggerMallocSizeOf(
+    JSContext* cx, mozilla::MallocSizeOf mallocSizeOf) {
+  cx->runtime()->debuggerMallocSizeOf = mallocSizeOf;
+}
+
+JS_PUBLIC_API mozilla::MallocSizeOf JS::dbg::GetDebuggerMallocSizeOf(
+    JSContext* cx) {
+  return cx->runtime()->debuggerMallocSizeOf;
+}
+
+using JS::ubi::Census;
+using JS::ubi::CountBasePtr;
+using JS::ubi::CountTypePtr;
+
+// The takeCensus function works in three phases:
+//
+// 1) We examine the 'breakdown' property of our 'options' argument, and
+//    use that to build a CountType tree.
+//
+// 2) We create a count node for the root of our CountType tree, and then walk
+//    the heap, counting each node we find, expanding our tree of counts as we
+//    go.
+//
+// 3) We walk the tree of counts and produce JavaScript objects reporting the
+//    accumulated results.
+bool DebuggerMemory::CallData::takeCensus() {
+  Census census(cx);
+  CountTypePtr rootType;
+
+  RootedObject options(cx);
+  if (args.get(0).isObject()) {
+    options = &args[0].toObject();
+  }
+
+  if (!JS::ubi::ParseCensusOptions(cx, census, options, rootType)) {
+    return false;
+  }
+
+  JS::ubi::RootedCount rootCount(cx, rootType->makeCount());
+  if (!rootCount) {
+    return false;
+  }
+  JS::ubi::CensusHandler handler(census, rootCount,
+                                 cx->runtime()->debuggerMallocSizeOf);
+
+  Debugger* dbg = memory->getDebugger();
+  RootedObject dbgObj(cx, dbg->object);
+
+  // Populate our target set of debuggee zones.
+  for (WeakGlobalObjectSet::Range r = dbg->allDebuggees(); !r.empty();
+       r.popFront()) {
+    if (!census.targetZones.put(r.front()->zone())) {
+      return false;
+    }
+  }
+
+  {
+    Maybe<JS::AutoCheckCannotGC> maybeNoGC;
+    JS::ubi::RootList rootList(cx, maybeNoGC);
+    if (!rootList.init(dbgObj)) {
+      ReportOutOfMemory(cx);
+      return false;
+    }
+
+    JS::ubi::CensusTraversal traversal(cx, handler, maybeNoGC.ref());
+    traversal.wantNames = false;
+
+    if (!traversal.addStart(JS::ubi::Node(&rootList)) ||
+        !traversal.traverse()) {
+      ReportOutOfMemory(cx);
+      return false;
+    }
+  }
+
+  return handler.report(cx, args.rval());
+}
+
+/* Debugger.Memory property and method tables. */
+
+/* static */ const JSPropertySpec DebuggerMemory::properties[] = {
+    JS_DEBUG_PSGS("trackingAllocationSites", getTrackingAllocationSites,
+                  setTrackingAllocationSites),
+    JS_DEBUG_PSGS("maxAllocationsLogLength", getMaxAllocationsLogLength,
+                  setMaxAllocationsLogLength),
+    JS_DEBUG_PSGS("allocationSamplingProbability",
+                  getAllocationSamplingProbability,
+                  setAllocationSamplingProbability),
+    JS_DEBUG_PSG("allocationsLogOverflowed", getAllocationsLogOverflowed),
+    JS_DEBUG_PSGS("onGarbageCollection", getOnGarbageCollection,
+                  setOnGarbageCollection),
+    JS_PS_END};
+
+/* static */ const JSFunctionSpec DebuggerMemory::methods[] = {
+    JS_DEBUG_FN("drainAllocationsLog", drainAllocationsLog, 0),
+    JS_DEBUG_FN("takeCensus", takeCensus, 0), JS_FS_END};