Add m-esr52 at 52.6.0

1 files changed, 519 insertions, 0 deletions

diff --git a/js/src/vm/UbiNode.cpp b/js/src/vm/UbiNode.cpp
new file mode 100644
index 000000000..538011bff
--- /dev/null
+++ b/js/src/vm/UbiNode.cpp
@@ -0,0 +1,519 @@
+/* -*- 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/UbiNode.h"
+
+#include "mozilla/Assertions.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/Range.h"
+#include "mozilla/Scoped.h"
+
+#include <algorithm>
+
+#include "jscntxt.h"
+#include "jsobj.h"
+#include "jsscript.h"
+#include "jsstr.h"
+
+#include "jit/IonCode.h"
+#include "js/Debug.h"
+#include "js/TracingAPI.h"
+#include "js/TypeDecls.h"
+#include "js/Utility.h"
+#include "js/Vector.h"
+#include "vm/Debugger.h"
+#include "vm/EnvironmentObject.h"
+#include "vm/GlobalObject.h"
+#include "vm/Scope.h"
+#include "vm/Shape.h"
+#include "vm/String.h"
+#include "vm/Symbol.h"
+
+#include "jsobjinlines.h"
+#include "vm/Debugger-inl.h"
+
+using namespace js;
+
+using mozilla::Some;
+using mozilla::RangedPtr;
+using JS::DispatchTyped;
+using JS::HandleValue;
+using JS::Value;
+using JS::ZoneSet;
+using JS::ubi::AtomOrTwoByteChars;
+using JS::ubi::CoarseType;
+using JS::ubi::Concrete;
+using JS::ubi::Edge;
+using JS::ubi::EdgeRange;
+using JS::ubi::Node;
+using JS::ubi::EdgeVector;
+using JS::ubi::StackFrame;
+using JS::ubi::TracerConcrete;
+using JS::ubi::TracerConcreteWithCompartment;
+
+struct CopyToBufferMatcher
+{
+    RangedPtr<char16_t> destination;
+    size_t              maxLength;
+
+    CopyToBufferMatcher(RangedPtr<char16_t> destination, size_t maxLength)
+      : destination(destination)
+      , maxLength(maxLength)
+    { }
+
+    template<typename CharT>
+    static size_t
+    copyToBufferHelper(const CharT* src, RangedPtr<char16_t> dest, size_t length)
+    {
+        size_t i = 0;
+        for ( ; i < length; i++)
+            dest[i] = src[i];
+        return i;
+    }
+
+    size_t
+    match(JSAtom* atom)
+    {
+        if (!atom)
+            return 0;
+
+        size_t length = std::min(atom->length(), maxLength);
+        JS::AutoCheckCannotGC noGC;
+        return atom->hasTwoByteChars()
+            ? copyToBufferHelper(atom->twoByteChars(noGC), destination, length)
+            : copyToBufferHelper(atom->latin1Chars(noGC), destination, length);
+    }
+
+    size_t
+    match(const char16_t* chars)
+    {
+        if (!chars)
+            return 0;
+
+        size_t length = std::min(js_strlen(chars), maxLength);
+        return copyToBufferHelper(chars, destination, length);
+    }
+};
+
+size_t
+JS::ubi::AtomOrTwoByteChars::copyToBuffer(RangedPtr<char16_t> destination, size_t length)
+{
+    CopyToBufferMatcher m(destination, length);
+    return match(m);
+}
+
+struct LengthMatcher
+{
+    size_t
+    match(JSAtom* atom)
+    {
+        return atom ? atom->length() : 0;
+    }
+
+    size_t
+    match(const char16_t* chars)
+    {
+        return chars ? js_strlen(chars) : 0;
+    }
+};
+
+size_t
+JS::ubi::AtomOrTwoByteChars::length()
+{
+    LengthMatcher m;
+    return match(m);
+}
+
+size_t
+StackFrame::source(RangedPtr<char16_t> destination, size_t length) const
+{
+    auto s = source();
+    return s.copyToBuffer(destination, length);
+}
+
+size_t
+StackFrame::functionDisplayName(RangedPtr<char16_t> destination, size_t length) const
+{
+    auto name = functionDisplayName();
+    return name.copyToBuffer(destination, length);
+}
+
+size_t
+StackFrame::sourceLength()
+{
+    return source().length();
+}
+
+size_t
+StackFrame::functionDisplayNameLength()
+{
+    return functionDisplayName().length();
+}
+
+// All operations on null ubi::Nodes crash.
+CoarseType Concrete<void>::coarseType() const      { MOZ_CRASH("null ubi::Node"); }
+const char16_t* Concrete<void>::typeName() const   { MOZ_CRASH("null ubi::Node"); }
+JS::Zone* Concrete<void>::zone() const             { MOZ_CRASH("null ubi::Node"); }
+JSCompartment* Concrete<void>::compartment() const { MOZ_CRASH("null ubi::Node"); }
+
+UniquePtr<EdgeRange>
+Concrete<void>::edges(JSContext*, bool) const {
+    MOZ_CRASH("null ubi::Node");
+}
+
+Node::Size
+Concrete<void>::size(mozilla::MallocSizeOf mallocSizeof) const
+{
+    MOZ_CRASH("null ubi::Node");
+}
+
+struct Node::ConstructFunctor : public js::BoolDefaultAdaptor<Value, false> {
+    template <typename T> bool operator()(T* t, Node* node) { node->construct(t); return true; }
+};
+
+Node::Node(const JS::GCCellPtr &thing)
+{
+    DispatchTyped(ConstructFunctor(), thing, this);
+}
+
+Node::Node(HandleValue value)
+{
+    if (!DispatchTyped(ConstructFunctor(), value, this))
+        construct<void>(nullptr);
+}
+
+Value
+Node::exposeToJS() const
+{
+    Value v;
+
+    if (is<JSObject>()) {
+        JSObject& obj = *as<JSObject>();
+        if (obj.is<js::EnvironmentObject>()) {
+            v.setUndefined();
+        } else if (obj.is<JSFunction>() && js::IsInternalFunctionObject(obj)) {
+            v.setUndefined();
+        } else {
+            v.setObject(obj);
+        }
+    } else if (is<JSString>()) {
+        v.setString(as<JSString>());
+    } else if (is<JS::Symbol>()) {
+        v.setSymbol(as<JS::Symbol>());
+    } else {
+        v.setUndefined();
+    }
+
+    ExposeValueToActiveJS(v);
+
+    return v;
+}
+
+
+// A JS::CallbackTracer subclass that adds a Edge to a Vector for each
+// edge on which it is invoked.
+class EdgeVectorTracer : public JS::CallbackTracer {
+    // The vector to which we add Edges.
+    EdgeVector* vec;
+
+    // True if we should populate the edge's names.
+    bool wantNames;
+
+    void onChild(const JS::GCCellPtr& thing) override {
+        if (!okay)
+            return;
+
+        // Don't trace permanent atoms and well-known symbols that are owned by
+        // a parent JSRuntime.
+        if (thing.is<JSString>() && thing.as<JSString>().isPermanentAtom())
+            return;
+        if (thing.is<JS::Symbol>() && thing.as<JS::Symbol>().isWellKnownSymbol())
+            return;
+
+        char16_t* name16 = nullptr;
+        if (wantNames) {
+            // Ask the tracer to compute an edge name for us.
+            char buffer[1024];
+            getTracingEdgeName(buffer, sizeof(buffer));
+            const char* name = buffer;
+
+            // Convert the name to char16_t characters.
+            name16 = js_pod_malloc<char16_t>(strlen(name) + 1);
+            if (!name16) {
+                okay = false;
+                return;
+            }
+
+            size_t i;
+            for (i = 0; name[i]; i++)
+                name16[i] = name[i];
+            name16[i] = '\0';
+        }
+
+        // The simplest code is correct! The temporary Edge takes
+        // ownership of name; if the append succeeds, the vector element
+        // then takes ownership; if the append fails, then the temporary
+        // retains it, and its destructor will free it.
+        if (!vec->append(mozilla::Move(Edge(name16, Node(thing))))) {
+            okay = false;
+            return;
+        }
+    }
+
+  public:
+    // True if no errors (OOM, say) have yet occurred.
+    bool okay;
+
+    EdgeVectorTracer(JSRuntime* rt, EdgeVector* vec, bool wantNames)
+      : JS::CallbackTracer(rt),
+        vec(vec),
+        wantNames(wantNames),
+        okay(true)
+    { }
+};
+
+
+// An EdgeRange concrete class that simply holds a vector of Edges,
+// populated by the init method.
+class SimpleEdgeRange : public EdgeRange {
+    EdgeVector edges;
+    size_t i;
+
+    void settle() {
+        front_ = i < edges.length() ? &edges[i] : nullptr;
+    }
+
+  public:
+    explicit SimpleEdgeRange() : edges(), i(0) { }
+
+    bool init(JSRuntime* rt, void* thing, JS::TraceKind kind, bool wantNames = true) {
+        EdgeVectorTracer tracer(rt, &edges, wantNames);
+        js::TraceChildren(&tracer, thing, kind);
+        settle();
+        return tracer.okay;
+    }
+
+    void popFront() override { i++; settle(); }
+};
+
+
+template<typename Referent>
+JS::Zone*
+TracerConcrete<Referent>::zone() const
+{
+    return get().zoneFromAnyThread();
+}
+
+template JS::Zone* TracerConcrete<JSScript>::zone() const;
+template JS::Zone* TracerConcrete<js::LazyScript>::zone() const;
+template JS::Zone* TracerConcrete<js::Shape>::zone() const;
+template JS::Zone* TracerConcrete<js::BaseShape>::zone() const;
+template JS::Zone* TracerConcrete<js::ObjectGroup>::zone() const;
+template JS::Zone* TracerConcrete<js::Scope>::zone() const;
+template JS::Zone* TracerConcrete<JS::Symbol>::zone() const;
+template JS::Zone* TracerConcrete<JSString>::zone() const;
+
+template<typename Referent>
+UniquePtr<EdgeRange>
+TracerConcrete<Referent>::edges(JSContext* cx, bool wantNames) const {
+    UniquePtr<SimpleEdgeRange, JS::DeletePolicy<SimpleEdgeRange>> range(js_new<SimpleEdgeRange>());
+    if (!range)
+        return nullptr;
+
+    if (!range->init(cx, ptr, JS::MapTypeToTraceKind<Referent>::kind, wantNames))
+        return nullptr;
+
+    return UniquePtr<EdgeRange>(range.release());
+}
+
+template UniquePtr<EdgeRange> TracerConcrete<JSScript>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<js::LazyScript>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<js::Shape>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<js::BaseShape>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<js::ObjectGroup>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<js::Scope>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<JS::Symbol>::edges(JSContext* cx, bool wantNames) const;
+template UniquePtr<EdgeRange> TracerConcrete<JSString>::edges(JSContext* cx, bool wantNames) const;
+
+template<typename Referent>
+JSCompartment*
+TracerConcreteWithCompartment<Referent>::compartment() const
+{
+    return TracerBase::get().compartment();
+}
+
+template JSCompartment* TracerConcreteWithCompartment<JSScript>::compartment() const;
+
+bool
+Concrete<JSObject>::hasAllocationStack() const
+{
+    return !!js::Debugger::getObjectAllocationSite(get());
+}
+
+StackFrame
+Concrete<JSObject>::allocationStack() const
+{
+    MOZ_ASSERT(hasAllocationStack());
+    return StackFrame(js::Debugger::getObjectAllocationSite(get()));
+}
+
+const char*
+Concrete<JSObject>::jsObjectClassName() const
+{
+    return Concrete::get().getClass()->name;
+}
+
+bool
+Concrete<JSObject>::jsObjectConstructorName(JSContext* cx, UniqueTwoByteChars& outName) const
+{
+    JSAtom* name = Concrete::get().maybeConstructorDisplayAtom();
+    if (!name) {
+        outName.reset(nullptr);
+        return true;
+    }
+
+    auto len = JS_GetStringLength(name);
+    auto size = len + 1;
+
+    outName.reset(cx->pod_malloc<char16_t>(size * sizeof(char16_t)));
+    if (!outName)
+        return false;
+
+    mozilla::Range<char16_t> chars(outName.get(), size);
+    if (!JS_CopyStringChars(cx, chars, name))
+        return false;
+
+    outName[len] = '\0';
+    return true;
+}
+
+const char16_t Concrete<JS::Symbol>::concreteTypeName[] = u"JS::Symbol";
+const char16_t Concrete<JSScript>::concreteTypeName[] = u"JSScript";
+const char16_t Concrete<js::LazyScript>::concreteTypeName[] = u"js::LazyScript";
+const char16_t Concrete<js::jit::JitCode>::concreteTypeName[] = u"js::jit::JitCode";
+const char16_t Concrete<js::Shape>::concreteTypeName[] = u"js::Shape";
+const char16_t Concrete<js::BaseShape>::concreteTypeName[] = u"js::BaseShape";
+const char16_t Concrete<js::ObjectGroup>::concreteTypeName[] = u"js::ObjectGroup";
+const char16_t Concrete<js::Scope>::concreteTypeName[] = u"js::Scope";
+
+namespace JS {
+namespace ubi {
+
+RootList::RootList(JSContext* cx, Maybe<AutoCheckCannotGC>& noGC, bool wantNames /* = false */)
+  : noGC(noGC),
+    cx(cx),
+    edges(),
+    wantNames(wantNames)
+{ }
+
+
+bool
+RootList::init()
+{
+    EdgeVectorTracer tracer(cx, &edges, wantNames);
+    js::TraceRuntime(&tracer);
+    if (!tracer.okay)
+        return false;
+    noGC.emplace(cx);
+    return true;
+}
+
+bool
+RootList::init(CompartmentSet& debuggees)
+{
+    EdgeVector allRootEdges;
+    EdgeVectorTracer tracer(cx, &allRootEdges, wantNames);
+
+    ZoneSet debuggeeZones;
+    if (!debuggeeZones.init())
+        return false;
+    for (auto range = debuggees.all(); !range.empty(); range.popFront()) {
+        if (!debuggeeZones.put(range.front()->zone()))
+            return false;
+    }
+
+    js::TraceRuntime(&tracer);
+    if (!tracer.okay)
+        return false;
+    TraceIncomingCCWs(&tracer, debuggees);
+    if (!tracer.okay)
+        return false;
+
+    for (EdgeVector::Range r = allRootEdges.all(); !r.empty(); r.popFront()) {
+        Edge& edge = r.front();
+
+        JSCompartment* compartment = edge.referent.compartment();
+        if (compartment && !debuggees.has(compartment))
+            continue;
+
+        Zone* zone = edge.referent.zone();
+        if (zone && !debuggeeZones.has(zone))
+            continue;
+
+        if (!edges.append(mozilla::Move(edge)))
+            return false;
+    }
+
+    noGC.emplace(cx);
+    return true;
+}
+
+bool
+RootList::init(HandleObject debuggees)
+{
+    MOZ_ASSERT(debuggees && JS::dbg::IsDebugger(*debuggees));
+    js::Debugger* dbg = js::Debugger::fromJSObject(debuggees.get());
+
+    CompartmentSet debuggeeCompartments;
+    if (!debuggeeCompartments.init())
+        return false;
+
+    for (js::WeakGlobalObjectSet::Range r = dbg->allDebuggees(); !r.empty(); r.popFront()) {
+        if (!debuggeeCompartments.put(r.front()->compartment()))
+            return false;
+    }
+
+    if (!init(debuggeeCompartments))
+        return false;
+
+    // Ensure that each of our debuggee globals are in the root list.
+    for (js::WeakGlobalObjectSet::Range r = dbg->allDebuggees(); !r.empty(); r.popFront()) {
+        if (!addRoot(JS::ubi::Node(static_cast<JSObject*>(r.front())),
+                     u"debuggee global"))
+        {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+bool
+RootList::addRoot(Node node, const char16_t* edgeName)
+{
+    MOZ_ASSERT(noGC.isSome());
+    MOZ_ASSERT_IF(wantNames, edgeName);
+
+    UniqueTwoByteChars name;
+    if (edgeName) {
+        name = js::DuplicateString(edgeName);
+        if (!name)
+            return false;
+    }
+
+    return edges.append(mozilla::Move(Edge(name.release(), node)));
+}
+
+const char16_t Concrete<RootList>::concreteTypeName[] = u"JS::ubi::RootList";
+
+UniquePtr<EdgeRange>
+Concrete<RootList>::edges(JSContext* cx, bool wantNames) const {
+    MOZ_ASSERT_IF(wantNames, get().wantNames);
+    return UniquePtr<EdgeRange>(js_new<PreComputedEdgeRange>(get().edges));
+}
+
+} // namespace ubi
+} // namespace JS