From 3825531912eb365a28d55459f6b00041a026179b Mon Sep 17 00:00:00 2001
From: Luke Wagner <luke@mozilla.com>
Date: Thu, 14 Feb 2013 15:08:15 -0800
Subject: [PATCH] Bug 841619 - Factor out an ArrayBufferObject::changeContents
 from uninlineData (r=sfink)

--HG--
extra : rebase_source : 0f3828f1cd07e447540b28ba38f02e2bdd75aa04
---
 js/src/jstypedarray.cpp | 48 ++++++++++++++++++++++-------------------
 js/src/jstypedarray.h   |  1 +
 2 files changed, 27 insertions(+), 22 deletions(-)

diff --git a/js/src/jstypedarray.cpp b/js/src/jstypedarray.cpp
index 707dbfcdb4fe..e6e05266386e 100644
--- a/js/src/jstypedarray.cpp
+++ b/js/src/jstypedarray.cpp
@@ -273,36 +273,40 @@ GetViewList(ArrayBufferObject *obj)
 #endif
 }
 
+void
+ArrayBufferObject::changeContents(ObjectElements *newHeader)
+{
+   // Grab out data before invalidating it.
+   uint32_t byteLengthCopy = byteLength();
+   uintptr_t oldDataPointer = uintptr_t(dataPointer());
+   JSObject *viewListHead = *GetViewList(this);
+
+   // Update all views.
+   uintptr_t newDataPointer = uintptr_t(newHeader->elements());
+   for (JSObject *view = viewListHead; view; view = NextView(view)) {
+       uintptr_t newDataPtr = uintptr_t(view->getPrivate()) - oldDataPointer + newDataPointer;
+       view->setPrivate(reinterpret_cast<uint8_t*>(newDataPtr));
+   }
+
+   // Change to the new header (now, so we can use GetViewList).
+   elements = newHeader->elements();
+
+   // Initialize 'newHeader'.
+   ArrayBufferObject::setElementsHeader(newHeader, byteLengthCopy);
+   *GetViewList(this) = viewListHead;
+}
+
 bool
 ArrayBufferObject::uninlineData(JSContext *maybecx)
 {
    if (hasDynamicElements())
        return true;
 
-   // Grab out data before invalidating it
-   uint32_t bytes = byteLength();
-   uintptr_t oldPointer = uintptr_t(dataPointer());
-   JSObject *view = *GetViewList(this);
-   JSObject *viewListHead = view;
-
-   ObjectElements *header = AllocateArrayBufferContents(maybecx, bytes,
-                                                        reinterpret_cast<uint8_t*>(oldPointer));
-   if (!header)
+   ObjectElements *newHeader = AllocateArrayBufferContents(maybecx, byteLength(), dataPointer());
+   if (!newHeader)
        return false;
-   elements = header->elements();
-   setElementsHeader(getElementsHeader(), bytes);
-
-   // Update all views
-   uintptr_t newPointer = uintptr_t(dataPointer());
-   while (view) {
-       uintptr_t newDataPtr = uintptr_t(view->getPrivate()) - oldPointer + newPointer;
-       view->setPrivate(reinterpret_cast<uint8_t*>(newDataPtr));
-       view = NextView(view);
-   }
-
-   // Restore the list of views
-   *GetViewList(this) = viewListHead;
 
+   changeContents(newHeader);
    return true;
 }
 
diff --git a/js/src/jstypedarray.h b/js/src/jstypedarray.h
index ccafea0b21ec..140278956f47 100644
--- a/js/src/jstypedarray.h
+++ b/js/src/jstypedarray.h
@@ -146,6 +146,7 @@ class ArrayBufferObject : public JSObject
     void addView(RawObject view);
 
     bool allocateSlots(JSContext *cx, uint32_t size, uint8_t *contents = NULL);
+    void changeContents(ObjectElements *newHeader);
 
     /*
      * Ensure that the data is not stored inline. Used when handing back a