Bug 1293419 - Make the trace logger use js::Thread instead of PRThread; r=terrence

This also introduces a hasher for js::Thread::Id.

js/src/threading/Thread.h

@@ -9,6 +9,7 @@
 
 #include "mozilla/Atomics.h"
 #include "mozilla/Attributes.h"
+#include "mozilla/HashFunctions.h"
 #include "mozilla/IndexSequence.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Tuple.h"
@@ -36,8 +37,11 @@ class ThreadTrampoline;
 class Thread
 {
 public:
+  struct Hasher;
+
   class Id
   {
+    friend struct Hasher;
     class PlatformData;
     void* platformData_[2];
 
@@ -68,6 +72,18 @@ public:
     size_t stackSize() const { return stackSize_; }
   };
 
+  // A js::HashTable hash policy for keying hash tables by js::Thread::Id.
+  struct Hasher
+  {
+    typedef Id Lookup;
+
+    static HashNumber hash(const Lookup& l);
+
+    static bool match(const Id& key, const Lookup& lookup) {
+      return key == lookup;
+    }
+  };
+
   // Create a Thread in an initially unjoinable state. A thread of execution can
   // be created for this Thread by calling |init|. Some of the thread's
   // properties may be controlled by passing options to this constructor.

js/src/threading/posix/Thread.cpp

@@ -37,6 +37,12 @@ class js::Thread::Id::PlatformData
   bool hasThread;
 };
 
+/* static */ js::HashNumber
+js::Thread::Hasher::hash(const Lookup& l)
+{
+  return mozilla::HashBytes(&l.platformData()->ptThread, sizeof(pthread_t));
+}
+
 inline js::Thread::Id::PlatformData*
 js::Thread::Id::platformData()
 {

js/src/threading/windows/Thread.cpp

@@ -21,6 +21,12 @@ class js::Thread::Id::PlatformData
   unsigned id;
 };
 
+/* static */ js::HashNumber
+js::Thread::Hasher::hash(const Lookup& l)
+{
+  return mozilla::HashBytes(l.platformData_, sizeof(l.platformData_));
+}
+
 inline js::Thread::Id::PlatformData*
 js::Thread::Id::platformData()
 {

js/src/vm/TraceLogging.cpp

@@ -893,14 +893,13 @@ TraceLoggerThreadState::forMainThread(PerThreadData* mainThread)
 TraceLoggerThread*
 js::TraceLoggerForCurrentThread()
 {
-    PRThread* thread = PR_GetCurrentThread();
     if (!EnsureTraceLoggerState())
         return nullptr;
-    return traceLoggerState->forThread(thread);
+    return traceLoggerState->forThread(ThisThread::GetId());
 }
 
 TraceLoggerThread*
-TraceLoggerThreadState::forThread(PRThread* thread)
+TraceLoggerThreadState::forThread(const Thread::Id& thread)
 {
     MOZ_ASSERT(initialized);
 

js/src/vm/TraceLogging.h

@@ -16,6 +16,7 @@
 #include "js/TypeDecls.h"
 #include "js/Vector.h"
 #include "threading/Mutex.h"
+#include "threading/Thread.h"
 #include "vm/TraceLoggingGraph.h"
 #include "vm/TraceLoggingTypes.h"
 
@@ -294,9 +295,9 @@ class TraceLoggerThread
 class TraceLoggerThreadState
 {
 #ifdef JS_TRACE_LOGGING
-    typedef HashMap<PRThread*,
+    typedef HashMap<Thread::Id,
                     TraceLoggerThread*,
-                    PointerHasher<PRThread*, 3>,
+                    Thread::Hasher,
                     SystemAllocPolicy> ThreadLoggerHashMap;
     typedef Vector<TraceLoggerThread*, 1, js::SystemAllocPolicy > MainThreadLoggers;
 
@@ -330,7 +331,7 @@ class TraceLoggerThreadState
 
     TraceLoggerThread* forMainThread(JSRuntime* runtime);
     TraceLoggerThread* forMainThread(jit::CompileRuntime* runtime);
-    TraceLoggerThread* forThread(PRThread* thread);
+    TraceLoggerThread* forThread(const Thread::Id& thread);
 
     bool isTextIdEnabled(uint32_t textId) {
         if (textId < TraceLogger_Last)