Bug 810192 - don't require a default constructor for Hash{Map,Set}; only construct objects for live elements (r=terrence)

js/public/Vector.h

@@ -512,6 +512,9 @@ template <class T, size_t N, class AllocPolicy>
 JS_ALWAYS_INLINE
 Vector<T, N, AllocPolicy>::Vector(MoveRef<Vector> rhs)
     : AllocPolicy(rhs)
+#ifdef DEBUG
+    , entered(false)
+#endif
 {
     mLength = rhs->mLength;
     mCapacity = rhs->mCapacity;

js/src/ion/IonAllocPolicy.h

@@ -94,6 +94,11 @@ class IonAllocPolicy
     void *malloc_(size_t bytes) {
         return GetIonContext()->temp->allocate(bytes);
     }
+    void *calloc_(size_t bytes) {
+        void *p = GetIonContext()->temp->allocate(bytes);
+        memset(p, 0, bytes);
+        return p;
+    }
     void *realloc_(void *p, size_t oldBytes, size_t bytes) {
         void *n = malloc_(bytes);
         if (!n)

js/src/jsalloc.h

@@ -18,6 +18,8 @@ namespace js {
  *  - public copy constructor, assignment, destructor
  *  - void *malloc_(size_t)
  *      Responsible for OOM reporting on NULL return value.
+ *  - void *calloc_(size_t)
+ *      Responsible for OOM reporting on NULL return value.
  *  - void *realloc_(size_t)
  *      Responsible for OOM reporting on NULL return value.
  *      The *used* bytes of the previous buffer is passed in
@@ -33,6 +35,7 @@ class SystemAllocPolicy
 {
   public:
     void *malloc_(size_t bytes) { return js_malloc(bytes); }
+    void *calloc_(size_t bytes) { return js_calloc(bytes); }
     void *realloc_(void *p, size_t oldBytes, size_t bytes) { return js_realloc(p, bytes); }
     void free_(void *p) { js_free(p); }
     void reportAllocOverflow() const {}
@@ -71,6 +74,13 @@ class TempAllocPolicy
         return p;
     }
 
+    void *calloc_(size_t bytes) {
+        void *p = js_calloc(bytes);
+        if (JS_UNLIKELY(!p))
+            p = onOutOfMemory(NULL, bytes);
+        return p;
+    }
+
     void *realloc_(void *p, size_t oldBytes, size_t bytes) {
         void *p2 = js_realloc(p, bytes);
         if (JS_UNLIKELY(!p2))

js/src/jsatom.h

@@ -38,8 +38,7 @@ HashId(jsid id)
     return mozilla::HashGeneric(JSID_BITS(id));
 }
 
-template<>
+struct JsidHasher
-struct DefaultHasher<jsid>
 {
     typedef jsid Lookup;
     static HashNumber hash(const Lookup &l) {

js/src/jscntxt.h

@@ -2194,6 +2194,7 @@ class RuntimeAllocPolicy
     RuntimeAllocPolicy(JSRuntime *rt) : runtime(rt) {}
     RuntimeAllocPolicy(JSContext *cx) : runtime(cx->runtime) {}
     void *malloc_(size_t bytes) { return runtime->malloc_(bytes); }
+    void *calloc_(size_t bytes) { return runtime->calloc_(bytes); }
     void *realloc_(void *p, size_t bytes) { return runtime->realloc_(p, bytes); }
     void free_(void *p) { js_free(p); }
     void reportAllocOverflow() const {}
@@ -2210,6 +2211,7 @@ class ContextAllocPolicy
     ContextAllocPolicy(JSContext *cx) : cx(cx) {}
     JSContext *context() const { return cx; }
     void *malloc_(size_t bytes) { return cx->malloc_(bytes); }
+    void *calloc_(size_t bytes) { return cx->calloc_(bytes); }
     void *realloc_(void *p, size_t oldBytes, size_t bytes) { return cx->realloc_(p, oldBytes, bytes); }
     void free_(void *p) { js_free(p); }
     void reportAllocOverflow() const { js_ReportAllocationOverflow(cx); }

js/src/jsgc.cpp

@@ -3249,10 +3249,11 @@ InCrossCompartmentMap(JSObject *src, Cell *dst, JSGCTraceKind dstKind)
 
     if (dstKind == JSTRACE_OBJECT) {
         Value key = ObjectValue(*static_cast<JSObject *>(dst));
-        WrapperMap::Ptr p = srccomp->crossCompartmentWrappers.lookup(key);
+        if (WrapperMap::Ptr p = srccomp->crossCompartmentWrappers.lookup(key)) {
             if (*p->value.unsafeGet() == ObjectValue(*src))
                 return true;
         }
+    }
 
     /*
      * If the cross-compartment edge is caused by the debugger, then we don't

js/src/json.cpp

@@ -630,7 +630,7 @@ js_Stringify(JSContext *cx, MutableHandleValue vp, JSObject *replacer_, Value sp
             if (replacer->isDenseArray())
                 len = Min(len, replacer->getDenseArrayCapacity());
 
-            HashSet<jsid> idSet(cx);
+            HashSet<jsid, JsidHasher> idSet(cx);
             if (!idSet.init(len))
                 return false;
 
@@ -667,7 +667,7 @@ js_Stringify(JSContext *cx, MutableHandleValue vp, JSObject *replacer_, Value sp
                 }
 
                 /* Step 4b(iv)(6). */
-                HashSet<jsid>::AddPtr p = idSet.lookupForAdd(id);
+                HashSet<jsid, JsidHasher>::AddPtr p = idSet.lookupForAdd(id);
                 if (!p) {
                     /* Step 4b(iv)(6)(a). */
                     if (!idSet.add(p, id) || !propertyList.append(id))

js/src/jspropertytree.cpp

@@ -148,7 +148,8 @@ PropertyTree::getChild(JSContext *cx, Shape *parent_, uint32_t nfixed, const Sta
         if (kid->matches(child))
             shape = kid;
     } else if (kidp->isHash()) {
-        shape = *kidp->toHash()->lookup(child);
+        if (KidsHash::Ptr p = kidp->toHash()->lookup(child))
+            shape = *p;
     } else {
         /* If kidp->isNull(), we always insert. */
     }

layout/style/nsNthIndexCache.h

@@ -55,6 +55,7 @@ private:
   class SystemAllocPolicy {
   public:
     void *malloc_(size_t bytes) { return ::malloc(bytes); }
+    void *calloc_(size_t bytes) { return ::calloc(bytes, 1); }
     void *realloc_(void *p, size_t bytes) { return ::realloc(p, bytes); }
     void free_(void *p) { ::free(p); }
     void reportAllocOverflow() const {}