1 files changed, 109 insertions, 0 deletions
diff --git a/layout/generic/nsFrameState.cpp b/layout/generic/nsFrameState.cpp
new file mode 100644
index 0000000000..2e5463e2d3
--- /dev/null
+++ b/layout/generic/nsFrameState.cpp
@@ -0,0 +1,109 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* constants for frame state bits and a type to store them in a uint64_t */
+
+#include "nsFrameState.h"
+
+#include "nsBlockFrame.h"
+#include "nsFlexContainerFrame.h"
+#include "nsGridContainerFrame.h"
+#include "nsGfxScrollFrame.h"
+#include "nsIFrame.h"
+#include "nsImageFrame.h"
+#include "nsInlineFrame.h"
+#include "nsPageFrame.h"
+#include "nsPlaceholderFrame.h"
+#include "nsRubyTextFrame.h"
+#include "nsRubyTextContainerFrame.h"
+#include "nsTableCellFrame.h"
+#include "nsTableRowFrame.h"
+#include "nsTableRowGroupFrame.h"
+#include "nsTextFrame.h"
+#include "mozilla/ISVGDisplayableFrame.h"
+#include "mozilla/SVGContainerFrame.h"
+
+namespace mozilla {
+
+#ifdef DEBUG
+nsCString GetFrameState(nsIFrame* aFrame) {
+  nsCString result;
+  AutoTArray<const char*, 3> groups;
+
+  nsFrameState state = aFrame->GetStateBits();
+
+  if (state == nsFrameState(0)) {
+    result.Assign('0');
+    return result;
+  }
+
+#  define FRAME_STATE_GROUP_CLASS(name_, class_)                        \
+    {                                                                   \
+      class_* frame = do_QueryFrame(aFrame);                            \
+      if (frame &&                                                      \
+          (groups.IsEmpty() || strcmp(groups.LastElement(), #name_))) { \
+        groups.AppendElement(#name_);                                   \
+      }                                                                 \
+    }
+#  define FRAME_STATE_BIT(group_, value_, name_)                            \
+    if ((state & NS_FRAME_STATE_BIT(value_)) && groups.Contains(#group_)) { \
+      if (!result.IsEmpty()) {                                              \
+        result.InsertLiteral(" | ", 0);                                     \
+      }                                                                     \
+      result.InsertLiteral(#name_, 0);                                      \
+      state = state & ~NS_FRAME_STATE_BIT(value_);                          \
+    }
+#  include "nsFrameStateBits.h"
+#  undef FRAME_STATE_GROUP_CLASS
+#  undef FRAME_STATE_BIT
+
+  if (state) {
+    result.AppendPrintf(" | 0x%0" PRIx64, static_cast<uint64_t>(state));
+  }
+
+  return result;
+}
+
+void PrintFrameState(nsIFrame* aFrame) {
+  printf("%s\n", GetFrameState(aFrame).get());
+}
+
+enum class FrameStateGroupId {
+#  define FRAME_STATE_GROUP_NAME(name_) name_,
+#  include "nsFrameStateBits.h"
+#  undef FRAME_STATE_GROUP_NAME
+
+  LENGTH
+};
+
+void DebugVerifyFrameStateBits() {
+  // Build an array of all of the bits used by each group.  While
+  // building this we assert that a bit isn't used multiple times within
+  // the same group.
+  nsFrameState bitsUsedPerGroup[size_t(FrameStateGroupId::LENGTH)] = {
+      nsFrameState(0)};
+
+#  define FRAME_STATE_BIT(group_, value_, name_)                           \
+    {                                                                      \
+      auto bit = NS_FRAME_STATE_BIT(value_);                               \
+      size_t group = size_t(FrameStateGroupId::group_);                    \
+      MOZ_ASSERT(!(bitsUsedPerGroup[group] & bit), #name_                  \
+                 " must not use a bit already declared within its group"); \
+      bitsUsedPerGroup[group] |= bit;                                      \
+    }
+
+#  include "nsFrameStateBits.h"
+#  undef FRAME_STATE_BIT
+
+  // FIXME: Can we somehow check across the groups as well???  In other
+  // words, find the pairs of groups that could be used on the same
+  // frame (Generic paired with everything else, and a few other pairs),
+  // and check that we don't have bits in common between those pairs.
+}
+
+#endif
+
+}  // namespace mozilla