[simulator] Make reference redirection thread-safe.

In the simulators, the ExternalReference constructor rewrites external
addresses, which involves mutating a linked list rooted in the isolate.

We already construct external references concurrently (at least in Turbofan),
but the list mutation was not thread-safe (though no crashes are known). This
CL adds the necessary locking.

BUG=v8:6048

Review-Url: https://codereview.chromium.org/2852983002
Cr-Commit-Position: refs/heads/master@{#45014}

src/arm/simulator-arm.cc

@@ -803,6 +803,8 @@ void Simulator::TearDown(base::CustomMatcherHashMap* i_cache,
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address_of_swi_instruction();
 }

src/arm/simulator-arm.h

@@ -361,7 +361,7 @@ class Simulator {
   static CachePage* GetCachePage(base::CustomMatcherHashMap* i_cache,
                                  void* page);
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(
       Isolate* isolate, void* external_function,
       v8::internal::ExternalReference::Type type);

src/arm64/simulator-arm64.cc

@@ -801,6 +801,8 @@ void Simulator::DoRuntimeCall(Instruction* instr) {
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address_of_redirect_call();
 }

src/arm64/simulator-arm64.h

@@ -273,7 +273,7 @@ class Simulator : public DecoderVisitor {
 
   void ResetState();
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(Isolate* isolate,
                                          void* external_function,
                                          ExternalReference::Type type);

src/assembler.h

@@ -818,6 +818,7 @@ class ExternalReference BASE_EMBEDDED {
 
   static void SetUp();
 
+  // These functions must use the isolate in a thread-safe way.
   typedef void* ExternalReferenceRedirector(Isolate* isolate, void* original,
                                             Type type);
 

src/isolate.h

@@ -1250,6 +1250,9 @@ class Isolate {
 
 #ifdef USE_SIMULATOR
   base::Mutex* simulator_i_cache_mutex() { return &simulator_i_cache_mutex_; }
+  base::Mutex* simulator_redirection_mutex() {
+    return &simulator_redirection_mutex_;
+  }
 #endif
 
   void set_allow_atomics_wait(bool set) { allow_atomics_wait_ = set; }
@@ -1570,6 +1573,7 @@ class Isolate {
 
 #ifdef USE_SIMULATOR
   base::Mutex simulator_i_cache_mutex_;
+  base::Mutex simulator_redirection_mutex_;
 #endif
 
   bool allow_atomics_wait_;

src/mips/simulator-mips.cc

@@ -1016,6 +1016,8 @@ void Simulator::TearDown(base::CustomMatcherHashMap* i_cache,
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address_of_swi_instruction();
 }

src/mips/simulator-mips.h

@@ -463,7 +463,7 @@ class Simulator {
   // Exceptions.
   void SignalException(Exception e);
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(Isolate* isolate,
                                          void* external_function,
                                          ExternalReference::Type type);

src/mips64/simulator-mips64.cc

@@ -949,6 +949,8 @@ void Simulator::TearDown(base::CustomMatcherHashMap* i_cache,
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address_of_swi_instruction();
 }

src/mips64/simulator-mips64.h

@@ -493,7 +493,7 @@ class Simulator {
   // Exceptions.
   void SignalException(Exception e);
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(Isolate* isolate,
                                          void* external_function,
                                          ExternalReference::Type type);

src/ppc/simulator-ppc.cc

@@ -894,6 +894,8 @@ void Simulator::TearDown(base::CustomMatcherHashMap* i_cache,
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address();
 }

src/ppc/simulator-ppc.h

@@ -341,7 +341,7 @@ class Simulator {
   static CachePage* GetCachePage(base::CustomMatcherHashMap* i_cache,
                                  void* page);
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(
       Isolate* isolate, void* external_function,
       v8::internal::ExternalReference::Type type);

src/s390/simulator-s390.cc

@@ -1644,6 +1644,8 @@ void Simulator::TearDown(base::CustomMatcherHashMap* i_cache,
 void* Simulator::RedirectExternalReference(Isolate* isolate,
                                            void* external_function,
                                            ExternalReference::Type type) {
+  base::LockGuard<base::Mutex> lock_guard(
+      isolate->simulator_redirection_mutex());
   Redirection* redirection = Redirection::Get(isolate, external_function, type);
   return redirection->address();
 }

src/s390/simulator-s390.h

@@ -440,7 +440,7 @@ class Simulator {
   static CachePage* GetCachePage(base::CustomMatcherHashMap* i_cache,
                                  void* page);
 
-  // Runtime call support.
+  // Runtime call support. Uses the isolate in a thread-safe way.
   static void* RedirectExternalReference(
       Isolate* isolate, void* external_function,
       v8::internal::ExternalReference::Type type);