Use variable length key (rather than accumulated matrix) as save layer hoisting key

src/core/SkRecordDraw.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkLayerInfo.h"
 #include "SkRecordDraw.h"
 #include "SkPatchUtils.h"
@@ skipping 664 matching lines @@
             dst.fLocalMat = src.fLocalMat;
             dst.fPreMat = src.fPreMat;
             dst.fPreMat.postConcat(fFillBounds.ctm());
             if (src.fPaint) {
                 dst.fPaint = SkNEW_ARGS(SkPaint, (*src.fPaint));
             }
             dst.fSaveLayerOpID = src.fSaveLayerOpID;
             dst.fRestoreOpID = src.fRestoreOpID;
             dst.fHasNestedLayers = src.fHasNestedLayers;
             dst.fIsNested = fSaveLayersInStack > 0 || src.fIsNested;
+
+            dst.fKeySize = fSaveLayerOpStack.count() + src.fKeySize;
+            dst.fKey = SkNEW_ARRAY(int, dst.fKeySize);
+            memcpy(dst.fKey, fSaveLayerOpStack.begin(), fSaveLayerOpStack.count() * sizeof(int));
+            memcpy(&dst.fKey[fSaveLayerOpStack.count()], src.fKey, src.fKeySize * sizeof(int));
         }
     }
 
     // Inform all the saveLayers already on the stack that they now have a
     // nested saveLayer inside them
     void updateStackForSaveLayer() {
         for (int index = fSaveLayerStack.count() - 1; index >= 0; --index) {
             if (fSaveLayerStack[index].fHasNestedSaveLayer) {
                 break;
             }
@@ skipping 35 matching lines @@
         block.fBounds = fFillBounds.getBounds(sli.fStartIndex);
         block.fLocalMat = fFillBounds.ctm();
         block.fPreMat = SkMatrix::I();
         if (sli.fPaint) {
             block.fPaint = SkNEW_ARGS(SkPaint, (*sli.fPaint));
         }
         block.fSaveLayerOpID = sli.fStartIndex;
         block.fRestoreOpID = fFillBounds.currentOp();
         block.fHasNestedLayers = sli.fHasNestedSaveLayer;
         block.fIsNested = fSaveLayersInStack > 0;
+
+        block.fKeySize = fSaveLayerOpStack.count();
+        block.fKey = SkNEW_ARRAY(int, block.fKeySize);
+        memcpy(block.fKey, fSaveLayerOpStack.begin(), block.fKeySize * sizeof(int));
     }
 
     // Used to collect saveLayer information for layer hoisting
-    int                   fSaveLayersInStack;
+    int                      fSaveLayersInStack;
     SkTDArray<SaveLayerInfo> fSaveLayerStack;
-    SkLayerInfo*          fAccelData;
+    SkTDArray<int>           fSaveLayerOpStack;
+    SkLayerInfo*             fAccelData;
 
     SkRecords::FillBounds fFillBounds;
 };
 
 }  // namespace SkRecords
 
 void SkRecordFillBounds(const SkRect& cullRect, const SkRecord& record, SkBBoxHierarchy* bbh) {
     SkRecords::FillBounds visitor(cullRect, record);
 
     for (unsigned curOp = 0; curOp < record.count(); curOp++) {
         visitor.setCurrentOp(curOp);
         record.visit<void>(curOp, visitor);
     }
 
     visitor.cleanUp(bbh);
 }
 
 void SkRecordComputeLayers(const SkRect& cullRect, const SkRecord& record,
                            SkBBoxHierarchy* bbh, SkLayerInfo* data) {
     SkRecords::CollectLayers visitor(cullRect, record, data);
 
     for (unsigned curOp = 0; curOp < record.count(); curOp++) {
         visitor.setCurrentOp(curOp);
         record.visit<void>(curOp, visitor);
     }
 
     visitor.cleanUp(bbh);
 }