From 961f447726346d943c24076f999fd7b1d4df8bf7 Mon Sep 17 00:00:00 2001
From: Steve Fink <sfink@mozilla.com>
Date: Mon, 18 Mar 2019 21:37:05 +0000
Subject: [PATCH] Bug 1257982 - root some hashtables r=jonco

Differential Revision: https://phabricator.services.mozilla.com/D23620

--HG--
extra : moz-landing-system : lando
---
 js/src/frontend/ParseContext.h  | 23 +++++++++++++++++++----
 js/src/vm/Debugger.cpp          |  6 +++---
 js/src/vm/EnvironmentObject.cpp |  6 +++---
 3 files changed, 25 insertions(+), 10 deletions(-)

diff --git a/js/src/frontend/ParseContext.h b/js/src/frontend/ParseContext.h
index b56250ed5b15..6673b61e73ba 100644
--- a/js/src/frontend/ParseContext.h
+++ b/js/src/frontend/ParseContext.h
@@ -78,6 +78,11 @@ class UsedNameTracker {
 
     UsedNameInfo(UsedNameInfo&& other) : uses_(std::move(other.uses_)) {}
 
+    UsedNameInfo& operator=(UsedNameInfo&& other) {
+      uses_ = std::move(other.uses_);
+      return *this;
+    }
+
     bool noteUsedInScope(uint32_t scriptId, uint32_t scopeId) {
       if (uses_.empty() || uses_.back().scopeId < scopeId) {
         return uses_.append(Use{scriptId, scopeId});
@@ -105,11 +110,13 @@ class UsedNameTracker {
     }
   };
 
-  using UsedNameMap = HashMap<JSAtom*, UsedNameInfo, DefaultHasher<JSAtom*>>;
+  using UsedNameMap = GCHashMap<JSAtom*, UsedNameInfo, DefaultHasher<JSAtom*>>;
 
  private:
-  // The map of names to chains of uses.
-  UsedNameMap map_;
+  // The map of names to chains of uses. UsedNameTracker is not used in LIFO
+  // order with Rooteds, so must use PersistentRooted (for the arbitrary
+  // ordering capability, not for persistence.)
+  PersistentRooted<UsedNameMap> map_;
 
   // Monotonically increasing id for all nested scripts.
   uint32_t scriptCounter_;
@@ -119,7 +126,7 @@ class UsedNameTracker {
 
  public:
   explicit UsedNameTracker(JSContext* cx)
-      : map_(cx), scriptCounter_(0), scopeCounter_(0) {}
+      : map_(cx, cx), scriptCounter_(0), scopeCounter_(0) {}
 
   uint32_t nextScriptId() {
     MOZ_ASSERT(scriptCounter_ != UINT32_MAX,
@@ -665,4 +672,12 @@ class ParseContext : public Nestable<ParseContext> {
 
 }  // namespace js
 
+namespace JS {
+
+template <>
+struct GCPolicy<js::frontend::UsedNameTracker::UsedNameInfo>
+    : public IgnoreGCPolicy {};
+
+}  // namespace JS
+
 #endif  // frontend_ParseContext_h
diff --git a/js/src/vm/Debugger.cpp b/js/src/vm/Debugger.cpp
index 58af14f1d2af..2e11922c14ea 100644
--- a/js/src/vm/Debugger.cpp
+++ b/js/src/vm/Debugger.cpp
@@ -4538,7 +4538,7 @@ class MOZ_STACK_CLASS Debugger::ScriptQuery : public Debugger::QueryBase {
         hasLine(false),
         line(0),
         innermost(false),
-        innermostForRealm(cx->zone()),
+        innermostForRealm(cx, cx->zone()),
         scriptVector(cx, ScriptVector(cx)),
         lazyScriptVector(cx, LazyScriptVector(cx)),
         wasmInstanceVector(cx, WasmInstanceObjectVector(cx)) {}
@@ -4806,14 +4806,14 @@ class MOZ_STACK_CLASS Debugger::ScriptQuery : public Debugger::QueryBase {
   bool innermost;
 
   using RealmToScriptMap =
-      HashMap<Realm*, JSScript*, DefaultHasher<Realm*>, ZoneAllocPolicy>;
+      GCHashMap<Realm*, JSScript*, DefaultHasher<Realm*>, ZoneAllocPolicy>;
 
   /*
    * For 'innermost' queries, a map from realms to the innermost script
    * we've seen so far in that realm. (Template instantiation code size
    * explosion ho!)
    */
-  RealmToScriptMap innermostForRealm;
+  Rooted<RealmToScriptMap> innermostForRealm;
 
   /*
    * Accumulate the scripts in an Rooted<ScriptVector> and
diff --git a/js/src/vm/EnvironmentObject.cpp b/js/src/vm/EnvironmentObject.cpp
index 6d3d2e4fe56c..df21feeaacdf 100644
--- a/js/src/vm/EnvironmentObject.cpp
+++ b/js/src/vm/EnvironmentObject.cpp
@@ -3719,7 +3719,7 @@ bool js::GetFrameEnvironmentAndScope(JSContext* cx, AbstractFramePtr frame,
 
 #ifdef DEBUG
 
-typedef HashSet<PropertyName*> PropertyNameSet;
+using PropertyNameSet = GCHashSet<PropertyName*>;
 
 static bool RemoveReferencedNames(JSContext* cx, HandleScript script,
                                   PropertyNameSet& remainingNames) {
@@ -3797,7 +3797,7 @@ static bool RemoveReferencedNames(JSContext* cx, HandleScript script,
 static bool AnalyzeEntrainedVariablesInScript(JSContext* cx,
                                               HandleScript script,
                                               HandleScript innerScript) {
-  PropertyNameSet remainingNames(cx);
+  Rooted<PropertyNameSet> remainingNames(cx, cx);
 
   for (BindingIter bi(script); bi; bi++) {
     if (bi.closedOver()) {
@@ -3809,7 +3809,7 @@ static bool AnalyzeEntrainedVariablesInScript(JSContext* cx,
     }
   }
 
-  if (!RemoveReferencedNames(cx, innerScript, remainingNames)) {
+  if (!RemoveReferencedNames(cx, innerScript, remainingNames.get())) {
     return false;
   }