Bug 743047 - Make the script atoms HeapPointers; r=billm

These are only initialized and then read from, but we need to barrier the init
so that we will have a remembered set entry for atoms that are in the nursery.

--HG--
extra : rebase_source : 9a5a1eb3e0c76d4624a978627ff901d336b0c540

js/src/jsatom.cpp

@@ -502,8 +502,10 @@ js_DumpAtoms(JSContext *cx, FILE *fp)
 
 JS_STATIC_ASSERT(TEMP_SIZE_START >= sizeof(JSHashTable));
 
+namespace js {
+
 void
-js_InitAtomMap(JSContext *cx, AtomIndexMap *indices, JSAtom **atoms)
+InitAtomMap(JSContext *cx, AtomIndexMap *indices, HeapPtrAtom *atoms)
 {
     if (indices->isMap()) {
         typedef AtomIndexMap::WordMap WordMap;
@@ -512,7 +514,7 @@ js_InitAtomMap(JSContext *cx, AtomIndexMap *indices, JSAtom **atoms)
             JSAtom *atom = r.front().key;
             jsatomid index = r.front().value;
             JS_ASSERT(index < indices->count());
-            atoms[index] = atom;
+            atoms[index].init(atom);
         }
     } else {
         for (const AtomIndexMap::InlineElem *it = indices->asInline(), *end = indices->inlineEnd();
@@ -521,13 +523,11 @@ js_InitAtomMap(JSContext *cx, AtomIndexMap *indices, JSAtom **atoms)
             if (!atom)
                 continue;
             JS_ASSERT(it->value < indices->count());
-            atoms[it->value] = atom;
+            atoms[it->value].init(atom);
         }
     }
 }
 
-namespace js {
-
 bool
 IndexToIdSlow(JSContext *cx, uint32_t index, jsid *idp)
 {

js/src/jsatom.h

@@ -470,15 +470,15 @@ inline bool
 js_InternNonIntElementId(JSContext *cx, JSObject *obj, const js::Value &idval,
                          jsid *idp, js::Value *vp);
 
+namespace js {
+
 /*
  * For all unmapped atoms recorded in al, add a mapping from the atom's index
  * to its address. map->length must already be set to the number of atoms in
  * the list and map->vector must point to pre-allocated memory.
  */
 extern void
-js_InitAtomMap(JSContext *cx, js::AtomIndexMap *indices, JSAtom **atoms);
-
-namespace js {
+InitAtomMap(JSContext *cx, AtomIndexMap *indices, HeapPtrAtom *atoms);
 
 template<XDRMode mode>
 bool

js/src/jscntxtinlines.h

@@ -390,7 +390,7 @@ CallSetter(JSContext *cx, JSObject *obj, jsid id, StrictPropertyOp op, unsigned
     return CallJSPropertyOpSetter(cx, op, obj, id, strict, vp);
 }
 
-static inline JSAtom **
+static inline HeapPtrAtom *
 FrameAtomBase(JSContext *cx, js::StackFrame *fp)
 {
     return fp->script()->atoms;

js/src/jsinterp.cpp

@@ -1509,7 +1509,7 @@ js::Interpret(JSContext *cx, StackFrame *entryFrame, InterpMode interpMode)
      * access. For less frequent object loads we have to recover the segment
      * from atoms pointer first.
      */
-    JSAtom **atoms = script->atoms;
+    HeapPtrAtom *atoms = script->atoms;
 
 #if JS_HAS_GENERATORS
     if (JS_UNLIKELY(regs.fp()->isGeneratorFrame())) {

js/src/jsscript.cpp

@@ -674,8 +674,16 @@ js::XDRScript(XDRState<mode> *xdr, JSScript **scriptp, JSScript *parentScript)
     }
 
     for (i = 0; i != natoms; ++i) {
-        if (!XDRAtom(xdr, &script->atoms[i]))
-            return false;
+        if (mode == XDR_DECODE) {
+            JSAtom *tmp = NULL;
+            if (!XDRAtom(xdr, &tmp))
+                return false;
+            script->atoms[i].init(tmp);
+        } else {
+            JSAtom *tmp = script->atoms[i];
+            if (!XDRAtom(xdr, &tmp))
+                return false;
+        }
     }
 
     /*
@@ -1106,7 +1114,7 @@ JSScript::NewScript(JSContext *cx, uint32_t length, uint32_t nsrcnotes, uint32_t
 
     if (natoms != 0) {
         script->natoms = natoms;
-        script->atoms = reinterpret_cast<JSAtom **>(cursor);
+        script->atoms = reinterpret_cast<HeapPtrAtom *>(cursor);
         cursor += natoms * sizeof(script->atoms[0]);
     }
 
@@ -1205,7 +1213,7 @@ JSScript::NewScriptFromEmitter(JSContext *cx, BytecodeEmitter *bce)
     nfixed = bce->inFunction() ? bce->bindings.countVars() : 0;
     JS_ASSERT(nfixed < SLOTNO_LIMIT);
     script->nfixed = uint16_t(nfixed);
-    js_InitAtomMap(cx, bce->atomIndices.getMap(), script->atoms);
+    InitAtomMap(cx, bce->atomIndices.getMap(), script->atoms);
 
     filename = bce->parser->tokenStream.getFilename();
     if (filename) {
@@ -1828,7 +1836,7 @@ JSScript::markChildren(JSTracer *trc)
 
     for (uint32_t i = 0; i < natoms; ++i) {
         if (atoms[i])
-            MarkStringUnbarriered(trc, &atoms[i], "atom");
+            MarkString(trc, &atoms[i], "atom");
     }
 
     if (JSScript::isValidOffset(objectsOffset)) {

js/src/jsscript.h

@@ -409,7 +409,7 @@ struct JSScript : public js::gc::Cell
                                    comment above NewScript() for details) */
 
     const char      *filename;  /* source filename or null */
-    JSAtom          **atoms;    /* maps immediate index to literal struct */
+    js::HeapPtrAtom *atoms;     /* maps immediate index to literal struct */
 
     JSPrincipals    *principals;/* principals for this script */
     JSPrincipals    *originPrincipals; /* see jsapi.h 'originPrincipals' comment */
@@ -755,7 +755,7 @@ struct JSScript : public js::gc::Cell
         return isValidOffset(closedVarsOffset) ? closedVars()->length : 0;
     }
 
-    JSAtom *getAtom(size_t index) {
+    js::HeapPtrAtom &getAtom(size_t index) const {
         JS_ASSERT(index < natoms);
         return atoms[index];
     }