Mark temporary paths created by SkCanvas for clipping as volatile

src/core/SkCanvas.cpp

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapDevice.h"
 #include "SkCanvas.h"
 #include "SkCanvasPriv.h"
@@ skipping 1593 matching lines @@
         fClipStack->clipDevRect(devR, op, isAA);
         fMCRec->fRasterClip.op(devR, this->getTopLayerBounds(), op, isAA);
     } else {
         // since we're rotated or some such thing, we convert the rect to a path
         // and clip against that, since it can handle any matrix. However, to
         // avoid recursion in the case where we are subclassed (e.g. Pictures)
         // we explicitly call "our" version of clipPath.
         SkPath  path;
 
         path.addRect(rect);
+        path.setIsVolatile(true);
         this->SkCanvas::onClipPath(path, op, edgeStyle);
     }
 
     fDeviceClipBounds = qr_clip_bounds(fMCRec->fRasterClip.getBounds());
 }
 
 void SkCanvas::clipRRect(const SkRRect& rrect, SkRegion::Op op, bool doAA) {
     this->checkForDeferredSave();
     ClipEdgeStyle edgeStyle = doAA ? kSoft_ClipEdgeStyle : kHard_ClipEdgeStyle;
     if (rrect.isRect()) {
@@ skipping 16 matching lines @@
         fClipStack->clipDevRRect(transformedRRect, op, kSoft_ClipEdgeStyle == edgeStyle);
 
         fMCRec->fRasterClip.op(transformedRRect, this->getTopLayerBounds(), op,
                                kSoft_ClipEdgeStyle == edgeStyle);
         fDeviceClipBounds = qr_clip_bounds(fMCRec->fRasterClip.getBounds());
         return;
     }
 
     SkPath path;
     path.addRRect(rrect);
+    path.setIsVolatile(true);
     // call the non-virtual version
     this->SkCanvas::onClipPath(path, op, edgeStyle);
 }
 
 void SkCanvas::clipPath(const SkPath& path, SkRegion::Op op, bool doAA) {
     this->checkForDeferredSave();
     ClipEdgeStyle edgeStyle = doAA ? kSoft_ClipEdgeStyle : kHard_ClipEdgeStyle;
 
     if (!path.isInverseFillType() && fMCRec->fMatrix.rectStaysRect()) {
         SkRect r;
@@ skipping 36 matching lines @@
 #endif
 
     AutoValidateClip avc(this);
 
     fDeviceCMDirty = true;
     if (!fAllowSoftClip) {
         edgeStyle = kHard_ClipEdgeStyle;
     }
 
     SkPath devPath;
-    path.transform(fMCRec->fMatrix, &devPath);
+    if (fMCRec->fMatrix.isIdentity()) {
+        devPath = path;
+    } else {
+        path.transform(fMCRec->fMatrix, &devPath);
+        devPath.setIsVolatile(true);
+    }
 
     // Check if the transfomation, or the original path itself
     // made us empty. Note this can also happen if we contained NaN
     // values. computing the bounds detects this, and will set our
     // bounds to empty if that is the case. (see SkRect::set(pts, count))
     if (devPath.getBounds().isEmpty()) {
         // resetting the path will remove any NaN or other wanky values
         // that might upset our scan converter.
         devPath.reset();
     }
@@ skipping 1675 matching lines @@
 
 SkAutoCanvasMatrixPaint::~SkAutoCanvasMatrixPaint() {
     fCanvas->restoreToCount(fSaveCount);
 }
 
 #ifdef SK_SUPPORT_LEGACY_NEW_SURFACE_API
 SkSurface* SkCanvas::newSurface(const SkImageInfo& info, const SkSurfaceProps* props) {
     return this->makeSurface(info, props).release();
 }
 #endif