explicitly initialize all entries in array of SkBaseMatrix, since we can't say

trunk/src/core/SkPixelRef.cpp

 
 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkPixelRef.h"
 #include "SkFlattenableBuffers.h"
 #include "SkThread.h"
 
 SK_DEFINE_INST_COUNT(SkPixelRef)
 
-// must be a power-of-2. undef to just use 1 mutex
-#define PIXELREF_MUTEX_RING_COUNT       32
 
-#ifdef PIXELREF_MUTEX_RING_COUNT
-    static int32_t gPixelRefMutexRingIndex;
-    static SK_DECLARE_MUTEX_ARRAY(gPixelRefMutexRing, PIXELREF_MUTEX_RING_COUNT);
-#else
-    SK_DECLARE_STATIC_MUTEX(gPixelRefMutex);
+#ifdef SK_USE_POSIX_THREADS
+
+    static SkBaseMutex gPixelRefMutexRing[] = {
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },

[bungeman-skia, 2013/04/11 21:47:06]

Since we always want this to be a power of two, would it be cleaner to say
something like 

#define DOUBLE(x) x x
#define ONE { PTHREAD_MUTEX_INITIALIZER },
#define THIRTY_TWO DOUBLE(DOUBLE(DOUBLE(DOUBLE(DOUBLE(ONE)))))

it might make the intent clearer, but isn't necessary.

+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+        { PTHREAD_MUTEX_INITIALIZER }, { PTHREAD_MUTEX_INITIALIZER },
+    };
+
+    // must be a power-of-2. undef to just use 1 mutex

[bungeman-skia, 2013/04/11 21:47:06]

SK_COMPILE_ASSERT the size if a power of 2?

Do the assert outside this ifdef since this always needs to be true.

+    #define PIXELREF_MUTEX_RING_COUNT SK_ARRAY_COUNT(gPixelRefMutexRing)
+
+#else // not pthreads
+
+    // must be a power-of-2. undef to just use 1 mutex
+    #define PIXELREF_MUTEX_RING_COUNT       32
+    static SkBaseMutex gPixelRefMutexRing[PIXELREF_MUTEX_RING_COUNT];
+
 #endif
 
 static SkBaseMutex* get_default_mutex() {
-#ifdef PIXELREF_MUTEX_RING_COUNT
+    static int32_t gPixelRefMutexRingIndex;
+
     // atomic_inc might be overkill here. It may be fine if once in a while
     // we hit a race-condition and two subsequent calls get the same index...
     int index = sk_atomic_inc(&gPixelRefMutexRingIndex);
     return &gPixelRefMutexRing[index & (PIXELREF_MUTEX_RING_COUNT - 1)];
-#else
-    return &gPixelRefMutex;
-#endif
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 int32_t SkNextPixelRefGenerationID();
 
 int32_t SkNextPixelRefGenerationID() {
     static int32_t  gPixelRefGenerationID;
     // do a loop in case our global wraps around, as we never want to
     // return a 0
@@ skipping 135 matching lines @@
 
 #ifdef SK_BUILD_FOR_ANDROID
 void SkPixelRef::globalRef(void* data) {
     this->ref();
 }
 
 void SkPixelRef::globalUnref() {
     this->unref();
 }
 #endif