Changeset 116129 in webkit

Timestamp:

May 4, 2012 11:28:05 AM (12 years ago)

Author:

tony@chromium.org

Message:

fix bit packing in FillLayer on Windows
​https://bugs.webkit.org/show_bug.cgi?id=85636

Reviewed by Ryosuke Niwa.

Use unsigned for all bit packed types. I manually verified that
the current uses of these member variables always assign true or false.

No new tests, adding a compile assert to verify bit packing.

• rendering/style/FillLayer.cpp:

(SameSizeAsFillLayer): Added compile assert.
(WebCore):
(WebCore::FillLayer::FillLayer): Reorder m_sizeLength so bit packed fields are adjacent.
(WebCore::FillLayer::operator=): Ditto.

• rendering/style/FillLayer.h:

(FillLayer): Convert bools to unsigned to match other bit packed fields.

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• rendering/style/FillLayer.cpp (modified) (7 diffs)
• rendering/style/FillLayer.h (modified) (2 diffs)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2012-05-04  Tony Chang  <tony@chromium.org>
+
+        fix bit packing in FillLayer on Windows
+        https://bugs.webkit.org/show_bug.cgi?id=85636
+
+        Reviewed by Ryosuke Niwa.
+
+        Use unsigned for all bit packed types. I manually verified that
+        the current uses of these member variables always assign true or false.
+
+        No new tests, adding a compile assert to verify bit packing.
+
+        * rendering/style/FillLayer.cpp:
+        (SameSizeAsFillLayer): Added compile assert.
+        (WebCore):
+        (WebCore::FillLayer::FillLayer): Reorder m_sizeLength so bit packed fields are adjacent.
+        (WebCore::FillLayer::operator=): Ditto.
+        * rendering/style/FillLayer.h:
+        (FillLayer): Convert bools to unsigned to match other bit packed fields.
+
 2012-05-04  Tommy Widenflycht  <tommyw@google.com>
 

trunk/Source/WebCore/rendering/style/FillLayer.cpp

@@ -24 +24 @@
 
 namespace WebCore {
+
+struct SameSizeAsFillLayer {
+    FillLayer* m_next;
+
+    RefPtr<StyleImage> m_image;
+
+    Length m_xPosition;
+    Length m_yPosition;
+
+    LengthSize m_sizeLength;
+
+    unsigned m_bitfields;
+};
+
+COMPILE_ASSERT(sizeof(FillLayer) == sizeof(SameSizeAsFillLayer), FillLayer_should_stay_small);
 
 FillLayer::FillLayer(EFillLayerType type)
@@ -30 +45 @@
     , m_xPosition(FillLayer::initialFillXPosition(type))
     , m_yPosition(FillLayer::initialFillYPosition(type))
+    , m_sizeLength(FillLayer::initialFillSizeLength(type))
     , m_attachment(FillLayer::initialFillAttachment(type))
     , m_clip(FillLayer::initialFillClip(type))
@@ -37 +53 @@
     , m_composite(FillLayer::initialFillComposite(type))
     , m_sizeType(SizeNone)
-    , m_sizeLength(FillLayer::initialFillSizeLength(type))
     , m_imageSet(false)
     , m_attachmentSet(false)
@@ -56 +71 @@
     , m_xPosition(o.m_xPosition)
     , m_yPosition(o.m_yPosition)
+    , m_sizeLength(o.m_sizeLength)
     , m_attachment(o.m_attachment)
     , m_clip(o.m_clip)
@@ -63 +79 @@
     , m_composite(o.m_composite)
     , m_sizeType(o.m_sizeType)
-    , m_sizeLength(o.m_sizeLength)
     , m_imageSet(o.m_imageSet)
     , m_attachmentSet(o.m_attachmentSet)
@@ -92 +107 @@
     m_xPosition = o.m_xPosition;
     m_yPosition = o.m_yPosition;
+    m_sizeLength = o.m_sizeLength;
     m_attachment = o.m_attachment;
     m_clip = o.m_clip;
@@ -99 +115 @@
     m_repeatY = o.m_repeatY;
     m_sizeType = o.m_sizeType;
-    m_sizeLength = o.m_sizeLength;
 
     m_imageSet = o.m_imageSet;

trunk/Source/WebCore/rendering/style/FillLayer.h

@@ -175 +175 @@
     Length m_yPosition;
 
+    LengthSize m_sizeLength;
+
     unsigned m_attachment : 2; // EFillAttachment
     unsigned m_clip : 2; // EFillBox
@@ -183 +185 @@
     unsigned m_sizeType : 2; // EFillSizeType
     
-    LengthSize m_sizeLength;
-
-    bool m_imageSet : 1;
-    bool m_attachmentSet : 1;
-    bool m_clipSet : 1;
-    bool m_originSet : 1;
-    bool m_repeatXSet : 1;
-    bool m_repeatYSet : 1;
-    bool m_xPosSet : 1;
-    bool m_yPosSet : 1;
-    bool m_compositeSet : 1;
+    unsigned m_imageSet : 1;
+    unsigned m_attachmentSet : 1;
+    unsigned m_clipSet : 1;
+    unsigned m_originSet : 1;
+    unsigned m_repeatXSet : 1;
+    unsigned m_repeatYSet : 1;
+    unsigned m_xPosSet : 1;
+    unsigned m_yPosSet : 1;
+    unsigned m_compositeSet : 1;
     
     unsigned m_type : 1; // EFillLayerType