Bug 1229277 - Introduce a map to match JSScript to script filenames instead of relying on ScriptSourceObject. r=nbp,jonco

--HG--
extra : rebase_source : 1c0c5cc201785e78dcae55313e9e25a1c862d7e1

js/src/jscompartment.cpp

@@ -85,6 +85,7 @@ JSCompartment::JSCompartment(Zone* zone, const JS::CompartmentOptions& options =
     randomKeyGenerator_(runtime_->forkRandomKeyGenerator()),
     watchpointMap(nullptr),
     scriptCountsMap(nullptr),
+    scriptNameMap(nullptr),
     debugScriptMap(nullptr),
     debugEnvs(nullptr),
     enumerators(nullptr),
@@ -115,6 +116,7 @@ JSCompartment::~JSCompartment()
     js_delete(jitCompartment_);
     js_delete(watchpointMap);
     js_delete(scriptCountsMap);
+    js_delete(scriptNameMap);
     js_delete(debugScriptMap);
     js_delete(debugEnvs);
     js_delete(objectMetadataTable);
@@ -810,6 +812,7 @@ JSCompartment::finishRoots()
         objectMetadataTable->clear();
 
     clearScriptCounts();
+    clearScriptNames();
 
     if (nonSyntacticLexicalEnvironments_)
         nonSyntacticLexicalEnvironments_->clear();
@@ -1008,6 +1011,14 @@ JSCompartment::fixupScriptMapsAfterMovingGC()
         }
     }
 
+    if (scriptNameMap) {
+        for (ScriptNameMap::Enum e(*scriptNameMap); !e.empty(); e.popFront()) {
+            JSScript* script = e.front().key();
+            if (!IsAboutToBeFinalizedUnbarriered(&script) && script != e.front().key())
+                e.rekeyFront(script);
+        }
+    }
+
     if (debugScriptMap) {
         for (DebugScriptMap::Enum e(*debugScriptMap); !e.empty(); e.popFront()) {
             JSScript* script = e.front().key();
@@ -1030,6 +1041,15 @@ JSCompartment::checkScriptMapsAfterMovingGC()
         }
     }
 
+    if (scriptNameMap) {
+        for (auto r = scriptNameMap->all(); !r.empty(); r.popFront()) {
+            JSScript* script = r.front().key();
+            CheckGCThingAfterMovingGC(script);
+            auto ptr = scriptNameMap->lookup(script);
+            MOZ_RELEASE_ASSERT(ptr.found() && &*ptr == &r.front());
+        }
+    }
+
     if (debugScriptMap) {
         for (auto r = debugScriptMap->all(); !r.empty(); r.popFront()) {
             JSScript* script = r.front().key();
@@ -1274,6 +1294,7 @@ JSCompartment::updateDebuggerObservesCoverage()
         return;
 
     clearScriptCounts();
+    clearScriptNames();
 }
 
 bool
@@ -1315,6 +1336,19 @@ JSCompartment::clearScriptCounts()
     scriptCountsMap = nullptr;
 }
 
+void
+JSCompartment::clearScriptNames()
+{
+    if (!scriptNameMap)
+        return;
+
+    for (ScriptNameMap::Range r = scriptNameMap->all(); !r.empty(); r.popFront())
+        js_delete(r.front().value());
+
+    js_delete(scriptNameMap);
+    scriptNameMap = nullptr;
+}
+
 void
 JSCompartment::clearBreakpointsIn(FreeOp* fop, js::Debugger* dbg, HandleObject handler)
 {

js/src/jscompartment.h

@@ -1090,6 +1090,7 @@ struct JSCompartment
     bool collectCoverageForDebug() const;
     bool collectCoverageForPGO() const;
     void clearScriptCounts();
+    void clearScriptNames();
 
     bool needsDelazificationForDebugger() const {
         return debugModeBits & DebuggerNeedsDelazification;
@@ -1116,6 +1117,7 @@ struct JSCompartment
     js::WatchpointMap* watchpointMap;
 
     js::ScriptCountsMap* scriptCountsMap;
+    js::ScriptNameMap* scriptNameMap;
 
     js::DebugScriptMap* debugScriptMap;
 

js/src/jsgc.cpp

@@ -7315,6 +7315,28 @@ gc::MergeCompartments(JSCompartment* source, JSCompartment* target)
 
     // Atoms which are marked in source's zone are now marked in target's zone.
     cx->atomMarking().adoptMarkedAtoms(target->zone(), source->zone());
+
+    // Merge script name maps in the target compartment's map.
+    if (cx->runtime()->lcovOutput().isEnabled()) {
+        AutoEnterOOMUnsafeRegion oomUnsafe;
+
+        if (!target->scriptNameMap) {
+            target->scriptNameMap = cx->new_<ScriptNameMap>();
+
+            if (!target->scriptNameMap)
+                oomUnsafe.crash("Failed to create a script name map.");
+
+            if (!target->scriptNameMap->init())
+                oomUnsafe.crash("Failed to initialize a script name map.");
+        }
+
+        for (ScriptNameMap::Range r = source->scriptNameMap->all(); !r.empty(); r.popFront()) {
+            JSScript* key = r.front().key();
+            const char* value = r.front().value();
+            if (!target->scriptNameMap->putNew(key, value))
+                oomUnsafe.crash("Failed to add an entry in the script name map.");
+        }
+    }
 }
 
 void

js/src/jsopcode.cpp

@@ -2966,7 +2966,6 @@ GenerateLcovInfo(JSContext* cx, JSCompartment* comp, GenericPrinter& out)
     coverage::LCovCompartment compCover;
     for (JSScript* topLevel: topScripts) {
         RootedScript topScript(cx, topLevel);
-        compCover.collectSourceFile(comp, &topScript->scriptSourceUnwrap());
 
         // We found the top-level script, visit all the functions reachable
         // from the top-level function, and delazify them.
@@ -2978,7 +2977,10 @@ GenerateLcovInfo(JSContext* cx, JSCompartment* comp, GenericPrinter& out)
         RootedFunction fun(cx);
         do {
             script = queue.popCopy();
-            compCover.collectCodeCoverageInfo(comp, script->sourceObject(), script);
+            if (!script->initScriptName(cx))
+                return false;
+            if (script->hasScriptName())
+                compCover.collectCodeCoverageInfo(comp, script);
 
             // Iterate from the last to the first object in order to have
             // the functions them visited in the opposite order when popping

js/src/jsscript.cpp

@@ -1159,6 +1159,15 @@ static inline ScriptCountsMap::Ptr GetScriptCountsMapEntry(JSScript* script)
     return p;
 }
 
+static inline ScriptNameMap::Ptr
+GetScriptNameMapEntry(JSScript* script)
+{
+    ScriptNameMap* map = script->compartment()->scriptNameMap;
+    auto p = map->lookup(script);
+    MOZ_ASSERT(p);
+    return p;
+}
+
 ScriptCounts&
 JSScript::getScriptCounts()
 {
@@ -1166,6 +1175,13 @@ JSScript::getScriptCounts()
     return *p->value();
 }
 
+const char*
+JSScript::getScriptName()
+{
+    auto p = GetScriptNameMapEntry(this);
+    return p->value();
+}
+
 js::PCCounts*
 ScriptCounts::maybeGetPCCounts(size_t offset) {
     PCCounts searched = PCCounts(offset);
@@ -1347,6 +1363,23 @@ JSScript::destroyScriptCounts(FreeOp* fop)
     }
 }
 
+void
+JSScript::destroyScriptName()
+{
+    auto p = GetScriptNameMapEntry(this);
+    compartment()->scriptNameMap->remove(p);
+}
+
+bool
+JSScript::hasScriptName()
+{
+    if (!compartment()->scriptNameMap)
+        return false;
+
+    auto p = compartment()->scriptNameMap->lookup(this);
+    return p.found();
+}
+
 void
 ScriptSourceObject::trace(JSTracer* trc, JSObject* obj)
 {
@@ -1367,12 +1400,6 @@ ScriptSourceObject::finalize(FreeOp* fop, JSObject* obj)
 {
     MOZ_ASSERT(fop->onActiveCooperatingThread());
     ScriptSourceObject* sso = &obj->as<ScriptSourceObject>();
-
-    // If code coverage is enabled, record the filename associated with this
-    // source object.
-    if (fop->runtime()->lcovOutput().isEnabled())
-        sso->compartment()->lcovOutput.collectSourceFile(sso->compartment(), sso);
-
     sso->source()->decref();
     sso->setReservedSlot(SOURCE_SLOT, PrivateValue(nullptr));
 }
@@ -2666,6 +2693,8 @@ JSScript::Create(JSContext* cx, const ReadOnlyCompileOptions& options,
     MOZ_ASSERT(script->getVersion() == options.version);     // assert that no overflow occurred
 
     script->setSourceObject(sourceObject);
+    if (cx->runtime()->lcovOutput().isEnabled() && !script->initScriptName(cx))
+        return nullptr;
     script->sourceStart_ = bufStart;
     script->sourceEnd_ = bufEnd;
     script->toStringStart_ = toStringStart;
@@ -2678,6 +2707,48 @@ JSScript::Create(JSContext* cx, const ReadOnlyCompileOptions& options,
     return script;
 }
 
+bool
+JSScript::initScriptName(JSContext* cx)
+{
+    MOZ_ASSERT(!hasScriptName());
+
+    if (!filename())
+        return true;
+
+    // Create compartment's scriptNameMap if necessary.
+    ScriptNameMap* map = compartment()->scriptNameMap;
+    if (!map) {
+        map = cx->new_<ScriptNameMap>();
+        if (!map) {
+            ReportOutOfMemory(cx);
+            return false;
+        }
+
+        if (!map->init()) {
+            js_delete(map);
+            ReportOutOfMemory(cx);
+            return false;
+        }
+
+        compartment()->scriptNameMap = map;
+    }
+
+    char* name = js_strdup(filename());
+    if (!name) {
+        ReportOutOfMemory(cx);
+        return false;
+    }
+
+    // Register the script name in the compartment's map.
+    if (!map->putNew(this, name)) {
+        js_delete(name);
+        ReportOutOfMemory(cx);
+        return false;
+    }
+
+    return true;
+}
+
 static inline uint8_t*
 AllocScriptData(JS::Zone* zone, size_t size)
 {
@@ -3090,8 +3161,10 @@ JSScript::finalize(FreeOp* fop)
 
     // Collect code coverage information for this script and all its inner
     // scripts, and store the aggregated information on the compartment.
-    if (fop->runtime()->lcovOutput().isEnabled())
-        compartment()->lcovOutput.collectCodeCoverageInfo(compartment(), sourceObject(), this);
+    if (fop->runtime()->lcovOutput().isEnabled() && hasScriptName()) {
+        compartment()->lcovOutput.collectCodeCoverageInfo(compartment(), this);
+        destroyScriptName();
+    }
 
     fop->runtime()->geckoProfiler().onScriptFinalized(this);
 

js/src/jsscript.h

@@ -240,6 +240,10 @@ typedef HashMap<JSScript*,
                 ScriptCounts*,
                 DefaultHasher<JSScript*>,
                 SystemAllocPolicy> ScriptCountsMap;
+typedef HashMap<JSScript*,
+                const char*,
+                DefaultHasher<JSScript*>,
+                SystemAllocPolicy> ScriptNameMap;
 
 class DebugScript
 {
@@ -1419,6 +1423,7 @@ class JSScript : public js::gc::TenuredCell
     void setIsDefaultClassConstructor() { isDefaultClassConstructor_ = true; }
 
     bool hasScriptCounts() const { return hasScriptCounts_; }
+    bool hasScriptName();
 
     bool hasFreezeConstraints() const { return hasFreezeConstraints_; }
     void setHasFreezeConstraints() { hasFreezeConstraints_ = true; }
@@ -1783,7 +1788,9 @@ class JSScript : public js::gc::TenuredCell
 
   public:
     bool initScriptCounts(JSContext* cx);
+    bool initScriptName(JSContext* cx);
     js::ScriptCounts& getScriptCounts();
+    const char* getScriptName();
     js::PCCounts* maybeGetPCCounts(jsbytecode* pc);
     const js::PCCounts* maybeGetThrowCounts(jsbytecode* pc);
     js::PCCounts* getThrowCounts(jsbytecode* pc);
@@ -1793,6 +1800,7 @@ class JSScript : public js::gc::TenuredCell
     js::jit::IonScriptCounts* getIonCounts();
     void releaseScriptCounts(js::ScriptCounts* counts);
     void destroyScriptCounts(js::FreeOp* fop);
+    void destroyScriptName();
     // The entry should be removed after using this function.
     void takeOverScriptCountsMapEntry(js::ScriptCounts* entryValue);
 

js/src/vm/CodeCoverage.cpp

@@ -63,9 +63,8 @@
 namespace js {
 namespace coverage {
 
-LCovSource::LCovSource(LifoAlloc* alloc, JSObject* sso)
-  : source_(sso),
-    outSF_(alloc),
+LCovSource::LCovSource(LifoAlloc* alloc, const char* name)
+  : name_(name),
     outFN_(alloc),
     outFNDA_(alloc),
     numFunctionsFound_(0),
@@ -76,7 +75,6 @@ LCovSource::LCovSource(LifoAlloc* alloc, JSObject* sso)
     outDA_(alloc),
     numLinesInstrumented_(0),
     numLinesHit_(0),
-    hasFilename_(false),
     hasTopLevelScript_(false)
 {
 }
@@ -85,10 +83,10 @@ void
 LCovSource::exportInto(GenericPrinter& out) const
 {
     // Only write if everything got recorded.
-    if (!hasFilename_ || !hasTopLevelScript_)
+    if (!hasTopLevelScript_)
         return;
 
-    outSF_.exportInto(out);
+    out.printf("SF:%s\n", name_);
 
     outFN_.exportInto(out);
     outFNDA_.exportInto(out);
@@ -106,17 +104,6 @@ LCovSource::exportInto(GenericPrinter& out) const
     out.put("end_of_record\n");
 }
 
-bool
-LCovSource::writeSourceFilename(ScriptSourceObject* sso)
-{
-    outSF_.printf("SF:%s\n", sso->source()->filename());
-    if (outSF_.hadOutOfMemory())
-        return false;
-
-    hasFilename_ = true;
-    return true;
-}
-
 bool
 LCovSource::writeScriptName(LSprinter& out, JSScript* script)
 {
@@ -404,8 +391,7 @@ LCovCompartment::LCovCompartment()
 }
 
 void
-LCovCompartment::collectCodeCoverageInfo(JSCompartment* comp, JSObject* sso,
-                                         JSScript* script)
+LCovCompartment::collectCodeCoverageInfo(JSCompartment* comp, JSScript* script)
 {
     // Skip any operation if we already some out-of memory issues.
     if (outTN_.hadOutOfMemory())
@@ -415,7 +401,7 @@ LCovCompartment::collectCodeCoverageInfo(JSCompartment* comp, JSObject* sso,
         return;
 
     // Get the existing source LCov summary, or create a new one.
-    LCovSource* source = lookupOrAdd(comp, sso);
+    LCovSource* source = lookupOrAdd(comp, script->getScriptName());
     if (!source)
         return;
 
@@ -426,31 +412,8 @@ LCovCompartment::collectCodeCoverageInfo(JSCompartment* comp, JSObject* sso,
     }
 }
 
-void
-LCovCompartment::collectSourceFile(JSCompartment* comp, ScriptSourceObject* sso)
-{
-    // Do not add sources if there is no file name associated to it.
-    if (!sso->source()->filename())
-        return;
-
-    // Skip any operation if we already some out-of memory issues.
-    if (outTN_.hadOutOfMemory())
-        return;
-
-    // Get the existing source LCov summary, or create a new one.
-    LCovSource* source = lookupOrAdd(comp, sso);
-    if (!source)
-        return;
-
-    // Write source filename into the LCovSource.
-    if (!source->writeSourceFilename(sso)) {
-        outTN_.reportOutOfMemory();
-        return;
-    }
-}
-
 LCovSource*
-LCovCompartment::lookupOrAdd(JSCompartment* comp, JSObject* sso)
+LCovCompartment::lookupOrAdd(JSCompartment* comp, const char* name)
 {
     // On the first call, write the compartment name, and allocate a LCovSource
     // vector in the LifoAlloc.
@@ -468,13 +431,13 @@ LCovCompartment::lookupOrAdd(JSCompartment* comp, JSObject* sso)
     } else {
         // Find the first matching source.
         for (LCovSource& source : *sources_) {
-            if (source.match(sso))
+            if (source.match(name))
                 return &source;
         }
     }
 
     // Allocate a new LCovSource for the current top-level.
-    if (!sources_->append(Move(LCovSource(&alloc_, sso)))) {
+    if (!sources_->append(Move(LCovSource(&alloc_, name)))) {
         outTN_.reportOutOfMemory();
         return nullptr;
     }

js/src/vm/CodeCoverage.h

@@ -28,16 +28,16 @@ class LCovCompartment;
 class LCovSource
 {
   public:
-    explicit LCovSource(LifoAlloc* alloc, JSObject* sso);
+    explicit LCovSource(LifoAlloc* alloc, const char* name);
 
-    // Whether the given script source object matches this LCovSource.
-    bool match(JSObject* sso) const {
-        return sso == source_;
+    // Whether the given script name matches this LCovSource.
+    bool match(const char* name) const {
+        return strcmp(name_, name) == 0;
     }
 
     // Whether the current source is complete and if it can be flushed.
     bool isComplete() const {
-        return hasFilename_ && hasTopLevelScript_;
+        return hasTopLevelScript_;
     }
 
     // Iterate over the bytecode and collect the lcov output based on the
@@ -48,19 +48,13 @@ class LCovSource
     // the runtime code coverage trace file.
     void exportInto(GenericPrinter& out) const;
 
-    // Write the script name in out.
-    bool writeSourceFilename(ScriptSourceObject* sso);
-
   private:
     // Write the script name in out.
     bool writeScriptName(LSprinter& out, JSScript* script);
 
   private:
-    // Weak pointer of the Script Source Object used by the current source.
-    JSObject *source_;
-
-    // LifoAlloc string which hold the filename of the source.
-    LSprinter outSF_;
+    // Name of the source file.
+    const char* name_;
 
     // LifoAlloc strings which hold the filename of each function as
     // well as the number of hits for each function.
@@ -80,7 +74,6 @@ class LCovSource
     size_t numLinesHit_;
 
     // Status flags.
-    bool hasFilename_ : 1;
     bool hasTopLevelScript_ : 1;
 };
 
@@ -90,10 +83,7 @@ class LCovCompartment
     LCovCompartment();
 
     // Collect code coverage information for the given source.
-    void collectCodeCoverageInfo(JSCompartment* comp, JSObject* sso, JSScript* topLevel);
-
-    // Create an ebtry for the current ScriptSourceObject.
-    void collectSourceFile(JSCompartment* comp, ScriptSourceObject* sso);
+    void collectCodeCoverageInfo(JSCompartment* comp, JSScript* topLevel);
 
     // Write the Lcov output in a buffer, such as the one associated with
     // the runtime code coverage trace file.
@@ -104,7 +94,7 @@ class LCovCompartment
     bool writeCompartmentName(JSCompartment* comp);
 
     // Return the LCovSource entry which matches the given ScriptSourceObject.
-    LCovSource* lookupOrAdd(JSCompartment* comp, JSObject* sso);
+    LCovSource* lookupOrAdd(JSCompartment* comp, const char* name);
 
   private:
     typedef mozilla::Vector<LCovSource, 16, LifoAllocPolicy<Fallible>> LCovSourceVector;