The Tor Browser: layout/generic/nsLineLayout.cpp@b8a032363ba2 (annotated)

layout/generic/nsLineLayout.cpp@b8a032363ba2 (annotated)

layout/generic/nsLineLayout.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* 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/. */
 /* state and methods used while laying out a single line of a block frame */
 // This has to be defined before nsLineLayout.h is included, because
 // nsLineLayout.h has a #include for plarena.h, which needs this defined:
 #define PL_ARENA_CONST_ALIGN_MASK (sizeof(void*)-1)
 #include "nsLineLayout.h"
 #include "SVGTextFrame.h"
 #include "nsBlockFrame.h"
 #include "nsStyleConsts.h"
 #include "nsContainerFrame.h"
 #include "nsFloatManager.h"
 #include "nsStyleContext.h"
 #include "nsPresContext.h"
 #include "nsRenderingContext.h"
 #include "nsGkAtoms.h"
 #include "nsIContent.h"
 #include "nsLayoutUtils.h"
 #include "nsTextFrame.h"
 #include "nsStyleStructInlines.h"
 #include "nsBidiPresUtils.h"
 #include <algorithm>
 #ifdef DEBUG
 #undef  NOISY_INLINEDIR_ALIGN
 #undef  NOISY_BLOCKDIR_ALIGN
 #undef  REALLY_NOISY_BLOCKDIR_ALIGN
 #undef  NOISY_REFLOW
 #undef  REALLY_NOISY_REFLOW
 #undef  NOISY_PUSHING
 #undef  REALLY_NOISY_PUSHING
 #undef  DEBUG_ADD_TEXT
 #undef  NOISY_MAX_ELEMENT_SIZE
 #undef  REALLY_NOISY_MAX_ELEMENT_SIZE
 #undef  NOISY_CAN_PLACE_FRAME
 #undef  NOISY_TRIM
 #undef  REALLY_NOISY_TRIM
 #endif
 using namespace mozilla;
 //----------------------------------------------------------------------
 #define FIX_BUG_50257
 nsLineLayout::nsLineLayout(nsPresContext* aPresContext,
                            nsFloatManager* aFloatManager,
                            const nsHTMLReflowState* aOuterReflowState,
                            const nsLineList::iterator* aLine)
   : mPresContext(aPresContext),
     mFloatManager(aFloatManager),
     mBlockReflowState(aOuterReflowState),
     mLastOptionalBreakContent(nullptr),
     mForceBreakContent(nullptr),
     mBlockRS(nullptr),/* XXX temporary */
     mLastOptionalBreakPriority(gfxBreakPriority::eNoBreak),
     mLastOptionalBreakContentOffset(-1),
     mForceBreakContentOffset(-1),
     mMinLineBSize(0),
     mTextIndent(0),
     mFirstLetterStyleOK(false),
     mIsTopOfPage(false),
     mImpactedByFloats(false),
     mLastFloatWasLetterFrame(false),
     mLineIsEmpty(false),
     mLineEndsInBR(false),
     mNeedBackup(false),
     mInFirstLine(false),
     mGotLineBox(false),
     mInFirstLetter(false),
     mHasBullet(false),
     mDirtyNextLine(false),
     mLineAtStart(false)
 {
   MOZ_ASSERT(aOuterReflowState, "aOuterReflowState must not be null");
   NS_ASSERTION(aFloatManager || aOuterReflowState->frame->GetType() ==
                                   nsGkAtoms::letterFrame,
                "float manager should be present");
   MOZ_COUNT_CTOR(nsLineLayout);
   // Stash away some style data that we need
   nsBlockFrame* blockFrame = do_QueryFrame(aOuterReflowState->frame);
   if (blockFrame)
     mStyleText = blockFrame->StyleTextForLineLayout();
   else
     mStyleText = aOuterReflowState->frame->StyleText();
   mLineNumber = 0;
   mTotalPlacedFrames = 0;
   mBStartEdge = 0;
   mTrimmableWidth = 0;
   mInflationMinFontSize =
     nsLayoutUtils::InflationMinFontSizeFor(aOuterReflowState->frame);
   // Instead of always pre-initializing the free-lists for frames and
   // spans, we do it on demand so that situations that only use a few
   // frames and spans won't waste a lot of time in unneeded
   // initialization.
   PL_INIT_ARENA_POOL(&mArena, "nsLineLayout", 1024);
   mFrameFreeList = nullptr;
   mSpanFreeList = nullptr;
   mCurrentSpan = mRootSpan = nullptr;
   mSpanDepth = 0;
   if (aLine) {
     mGotLineBox = true;
     mLineBox = *aLine;
   }
 }
 nsLineLayout::~nsLineLayout()
 {
   MOZ_COUNT_DTOR(nsLineLayout);
   NS_ASSERTION(nullptr == mRootSpan, "bad line-layout user");
   PL_FinishArenaPool(&mArena);
 }
 // Find out if the frame has a non-null prev-in-flow, i.e., whether it
 // is a continuation.
 inline bool
 HasPrevInFlow(nsIFrame *aFrame)
 {
   nsIFrame *prevInFlow = aFrame->GetPrevInFlow();
   return prevInFlow != nullptr;
 }
 void
 nsLineLayout::BeginLineReflow(nscoord aICoord, nscoord aBCoord,
                               nscoord aISize, nscoord aBSize,
                               bool aImpactedByFloats,
                               bool aIsTopOfPage,
                               WritingMode aWritingMode,
                               nscoord aContainerWidth)
 {
   NS_ASSERTION(nullptr == mRootSpan, "bad linelayout user");
   NS_WARN_IF_FALSE(aISize != NS_UNCONSTRAINEDSIZE,
                    "have unconstrained width; this should only result from "
                    "very large sizes, not attempts at intrinsic width "
                    "calculation");
 #ifdef DEBUG
   if ((aISize != NS_UNCONSTRAINEDSIZE) && CRAZY_SIZE(aISize)) {
     nsFrame::ListTag(stdout, mBlockReflowState->frame);
     printf(": Init: bad caller: width WAS %d(0x%x)\n",
            aISize, aISize);
   }
   if ((aBSize != NS_UNCONSTRAINEDSIZE) && CRAZY_SIZE(aBSize)) {
     nsFrame::ListTag(stdout, mBlockReflowState->frame);
     printf(": Init: bad caller: height WAS %d(0x%x)\n",
            aBSize, aBSize);
   }
 #endif
 #ifdef NOISY_REFLOW
   nsFrame::ListTag(stdout, mBlockReflowState->frame);
   printf(": BeginLineReflow: %d,%d,%d,%d impacted=%s %s\n",
          aICoord, aBCoord, aISize, aBSize,
          aImpactedByFloats?"true":"false",
          aIsTopOfPage ? "top-of-page" : "");
 #endif
 #ifdef DEBUG
   mSpansAllocated = mSpansFreed = mFramesAllocated = mFramesFreed = 0;
 #endif
   mFirstLetterStyleOK = false;
   mIsTopOfPage = aIsTopOfPage;
   mImpactedByFloats = aImpactedByFloats;
   mTotalPlacedFrames = 0;
   mLineIsEmpty = true;
   mLineAtStart = true;
   mLineEndsInBR = false;
   mSpanDepth = 0;
   mMaxStartBoxBSize = mMaxEndBoxBSize = 0;
   if (mGotLineBox) {
     mLineBox->ClearHasBullet();
   }
   PerSpanData* psd = NewPerSpanData();
   mCurrentSpan = mRootSpan = psd;
   psd->mReflowState = mBlockReflowState;
   psd->mIStart = aICoord;
   psd->mICoord = aICoord;
   psd->mIEnd = aICoord + aISize;
   mContainerWidth = aContainerWidth;
   // If we're in a constrained height frame, then we don't allow a
   // max line box width to take effect.
   if (!(LineContainerFrame()->GetStateBits() &
         NS_FRAME_IN_CONSTRAINED_HEIGHT)) {
     // If the available size is greater than the maximum line box width (if
     // specified), then we need to adjust the line box width to be at the max
     // possible width.
     nscoord maxLineBoxWidth =
       LineContainerFrame()->PresContext()->PresShell()->MaxLineBoxWidth();
     if (maxLineBoxWidth > 0 &&
         psd->mIEnd - psd->mIStart > maxLineBoxWidth) {
       psd->mIEnd = psd->mIStart + maxLineBoxWidth;
     }
   }
   mBStartEdge = aBCoord;
   psd->mNoWrap =
     !mStyleText->WhiteSpaceCanWrapStyle() || LineContainerFrame()->IsSVGText();
   psd->mWritingMode = aWritingMode;
   // If this is the first line of a block then see if the text-indent
   // property amounts to anything.
   if (0 == mLineNumber && !HasPrevInFlow(mBlockReflowState->frame)) {
     const nsStyleCoord &textIndent = mStyleText->mTextIndent;
     nscoord pctBasis = 0;
     if (textIndent.HasPercent()) {
       pctBasis =
         nsHTMLReflowState::GetContainingBlockContentWidth(mBlockReflowState);
       if (mGotLineBox) {
         mLineBox->DisableResizeReflowOptimization();
       }
     }
     nscoord indent = nsRuleNode::ComputeCoordPercentCalc(textIndent, pctBasis);
     mTextIndent = indent;
     psd->mICoord += indent;
   }
 }
 void
 nsLineLayout::EndLineReflow()
 {
 #ifdef NOISY_REFLOW
   nsFrame::ListTag(stdout, mBlockReflowState->frame);
   printf(": EndLineReflow: width=%d\n", mRootSpan->mICoord - mRootSpan->mIStart);
 #endif
   FreeSpan(mRootSpan);
   mCurrentSpan = mRootSpan = nullptr;
   NS_ASSERTION(mSpansAllocated == mSpansFreed, "leak");
   NS_ASSERTION(mFramesAllocated == mFramesFreed, "leak");
 #if 0
   static int32_t maxSpansAllocated = NS_LINELAYOUT_NUM_SPANS;
   static int32_t maxFramesAllocated = NS_LINELAYOUT_NUM_FRAMES;
   if (mSpansAllocated > maxSpansAllocated) {
     printf("XXX: saw a line with %d spans\n", mSpansAllocated);
     maxSpansAllocated = mSpansAllocated;
   }
   if (mFramesAllocated > maxFramesAllocated) {
     printf("XXX: saw a line with %d frames\n", mFramesAllocated);
     maxFramesAllocated = mFramesAllocated;
   }
 #endif
 }
 // XXX swtich to a single mAvailLineWidth that we adjust as each frame
 // on the line is placed. Each span can still have a per-span mICoord that
 // tracks where a child frame is going in its span; they don't need a
 // per-span mIStart?
 void
 nsLineLayout::UpdateBand(const nsRect& aNewAvailSpace,
                          nsIFrame* aFloatFrame)
 {
   WritingMode lineWM = mRootSpan->mWritingMode;
   LogicalRect availSpace(lineWM, aNewAvailSpace, mContainerWidth);
 #ifdef REALLY_NOISY_REFLOW
   printf("nsLL::UpdateBand %d, %d, %d, %d, (logical %d, %d, %d, %d); frame=%p\n  will set mImpacted to true\n",
          aNewAvailSpace.x, aNewAvailSpace.y,
          aNewAvailSpace.width, aNewAvailSpace.height,
          availSpace.IStart(lineWM), availSpace.BStart(lineWM),
          availSpace.ISize(lineWM), availSpace.BSize(lineWM),
          aFloatFrame);
 #endif
 #ifdef DEBUG
   if ((availSpace.ISize(lineWM) != NS_UNCONSTRAINEDSIZE) &&
       CRAZY_SIZE(availSpace.ISize(lineWM))) {
     nsFrame::ListTag(stdout, mBlockReflowState->frame);
     printf(": UpdateBand: bad caller: ISize WAS %d(0x%x)\n",
            availSpace.ISize(lineWM), availSpace.ISize(lineWM));
   }
   if ((availSpace.BSize(lineWM) != NS_UNCONSTRAINEDSIZE) &&
       CRAZY_SIZE(availSpace.BSize(lineWM))) {
     nsFrame::ListTag(stdout, mBlockReflowState->frame);
     printf(": UpdateBand: bad caller: BSize WAS %d(0x%x)\n",
            availSpace.BSize(lineWM), availSpace.BSize(lineWM));
   }
 #endif
   // Compute the difference between last times width and the new width
   NS_WARN_IF_FALSE(mRootSpan->mIEnd != NS_UNCONSTRAINEDSIZE &&
                    aNewAvailSpace.width != NS_UNCONSTRAINEDSIZE,
                    "have unconstrained width; this should only result from "
                    "very large sizes, not attempts at intrinsic width "
                    "calculation");
   // The root span's mIStart moves to aICoord
   nscoord deltaICoord = availSpace.IStart(lineWM) - mRootSpan->mIStart;
   // The width of all spans changes by this much (the root span's
   // mIEnd moves to aICoord + aISize, its new width is aISize)
   nscoord deltaISize = availSpace.ISize(lineWM) -
                        (mRootSpan->mIEnd - mRootSpan->mIStart);
 #ifdef NOISY_REFLOW
   nsFrame::ListTag(stdout, mBlockReflowState->frame);
   printf(": UpdateBand: %d,%d,%d,%d deltaISize=%d deltaICoord=%d\n",
          aNewAvailSpace.x, aNewAvailSpace.y,
          aNewAvailSpace.width, aNewAvailSpace.height, deltaISize, deltaICoord);
 #endif
   // Update the root span position
   mRootSpan->mIStart += deltaICoord;
   mRootSpan->mIEnd += deltaICoord;
   mRootSpan->mICoord += deltaICoord;
   // Now update the right edges of the open spans to account for any
   // change in available space width
   for (PerSpanData* psd = mCurrentSpan; psd; psd = psd->mParent) {
     psd->mIEnd += deltaISize;
     psd->mContainsFloat = true;
 #ifdef NOISY_REFLOW
     printf("  span %p: oldIEnd=%d newIEnd=%d\n",
            psd, psd->mIEnd - deltaISize, psd->mIEnd);
 #endif
   }
   NS_ASSERTION(mRootSpan->mContainsFloat &&
                mRootSpan->mIStart == availSpace.IStart(lineWM) &&
                mRootSpan->mIEnd == availSpace.IEnd(lineWM),
                "root span was updated incorrectly?");
   // Update frame bounds
   // Note: Only adjust the outermost frames (the ones that are direct
   // children of the block), not the ones in the child spans. The reason
   // is simple: the frames in the spans have coordinates local to their
   // parent therefore they are moved when their parent span is moved.
   if (deltaICoord != 0) {
     for (PerFrameData* pfd = mRootSpan->mFirstFrame; pfd; pfd = pfd->mNext) {
       pfd->mBounds.IStart(lineWM) += deltaICoord;
     }
   }
   mBStartEdge = aNewAvailSpace.y;
   mImpactedByFloats = true;
   mLastFloatWasLetterFrame = nsGkAtoms::letterFrame == aFloatFrame->GetType();
 }
 nsLineLayout::PerSpanData*
 nsLineLayout::NewPerSpanData()
 {
   PerSpanData* psd = mSpanFreeList;
   if (!psd) {
     void *mem;
     PL_ARENA_ALLOCATE(mem, &mArena, sizeof(PerSpanData));
     if (!mem) {
       NS_RUNTIMEABORT("OOM");
     }
     psd = reinterpret_cast<PerSpanData*>(mem);
   }
   else {
     mSpanFreeList = psd->mNextFreeSpan;
   }
   psd->mParent = nullptr;
   psd->mFrame = nullptr;
   psd->mFirstFrame = nullptr;
   psd->mLastFrame = nullptr;
   psd->mContainsFloat = false;
   psd->mZeroEffectiveSpanBox = false;
   psd->mHasNonemptyContent = false;
 #ifdef DEBUG
   mSpansAllocated++;
 #endif
   return psd;
 }
 void
 nsLineLayout::BeginSpan(nsIFrame* aFrame,
                         const nsHTMLReflowState* aSpanReflowState,
                         nscoord aIStart, nscoord aIEnd,
                         nscoord* aBaseline)
 {
   NS_ASSERTION(aIEnd != NS_UNCONSTRAINEDSIZE,
                "should no longer be using unconstrained sizes");
 #ifdef NOISY_REFLOW
   nsFrame::IndentBy(stdout, mSpanDepth+1);
   nsFrame::ListTag(stdout, aFrame);
   printf(": BeginSpan leftEdge=%d rightEdge=%d\n", aIStart, aIEnd);
 #endif
   PerSpanData* psd = NewPerSpanData();
   // Link up span frame's pfd to point to its child span data
   PerFrameData* pfd = mCurrentSpan->mLastFrame;
   NS_ASSERTION(pfd->mFrame == aFrame, "huh?");
   pfd->mSpan = psd;
   // Init new span
   psd->mFrame = pfd;
   psd->mParent = mCurrentSpan;
   psd->mReflowState = aSpanReflowState;
   psd->mIStart = aIStart;
   psd->mICoord = aIStart;
   psd->mIEnd = aIEnd;
   psd->mBaseline = aBaseline;
   nsIFrame* frame = aSpanReflowState->frame;
   psd->mNoWrap = !frame->StyleText()->WhiteSpaceCanWrap(frame);
   psd->mWritingMode = aSpanReflowState->GetWritingMode();
   // Switch to new span
   mCurrentSpan = psd;
   mSpanDepth++;
 }
 nscoord
 nsLineLayout::EndSpan(nsIFrame* aFrame)
 {
   NS_ASSERTION(mSpanDepth > 0, "end-span without begin-span");
 #ifdef NOISY_REFLOW
   nsFrame::IndentBy(stdout, mSpanDepth);
   nsFrame::ListTag(stdout, aFrame);
   printf(": EndSpan width=%d\n", mCurrentSpan->mICoord - mCurrentSpan->mIStart);
 #endif
   PerSpanData* psd = mCurrentSpan;
   nscoord iSizeResult = psd->mLastFrame ? (psd->mICoord - psd->mIStart) : 0;
   mSpanDepth--;
   mCurrentSpan->mReflowState = nullptr;  // no longer valid so null it out!
   mCurrentSpan = mCurrentSpan->mParent;
   return iSizeResult;
 }
 int32_t
 nsLineLayout::GetCurrentSpanCount() const
 {
   NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user");
   int32_t count = 0;
   PerFrameData* pfd = mRootSpan->mFirstFrame;
   while (nullptr != pfd) {
     count++;
     pfd = pfd->mNext;
   }
   return count;
 }
 void
 nsLineLayout::SplitLineTo(int32_t aNewCount)
 {
   NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user");
 #ifdef REALLY_NOISY_PUSHING
   printf("SplitLineTo %d (current count=%d); before:\n", aNewCount,
          GetCurrentSpanCount());
   DumpPerSpanData(mRootSpan, 1);
 #endif
   PerSpanData* psd = mRootSpan;
   PerFrameData* pfd = psd->mFirstFrame;
   while (nullptr != pfd) {
     if (--aNewCount == 0) {
       // Truncate list at pfd (we keep pfd, but anything following is freed)
       PerFrameData* next = pfd->mNext;
       pfd->mNext = nullptr;
       psd->mLastFrame = pfd;
       // Now release all of the frames following pfd
       pfd = next;
       while (nullptr != pfd) {
         next = pfd->mNext;
         pfd->mNext = mFrameFreeList;
         mFrameFreeList = pfd;
 #ifdef DEBUG
         mFramesFreed++;
 #endif
         if (nullptr != pfd->mSpan) {
           FreeSpan(pfd->mSpan);
         }
         pfd = next;
       }
       break;
     }
     pfd = pfd->mNext;
   }
 #ifdef NOISY_PUSHING
   printf("SplitLineTo %d (current count=%d); after:\n", aNewCount,
          GetCurrentSpanCount());
   DumpPerSpanData(mRootSpan, 1);
 #endif
 }
 void
 nsLineLayout::PushFrame(nsIFrame* aFrame)
 {
   PerSpanData* psd = mCurrentSpan;
   NS_ASSERTION(psd->mLastFrame->mFrame == aFrame, "pushing non-last frame");
 #ifdef REALLY_NOISY_PUSHING
   nsFrame::IndentBy(stdout, mSpanDepth);
   printf("PushFrame %p, before:\n", psd);
   DumpPerSpanData(psd, 1);
 #endif
   // Take the last frame off of the span's frame list
   PerFrameData* pfd = psd->mLastFrame;
   if (pfd == psd->mFirstFrame) {
     // We are pushing away the only frame...empty the list
     psd->mFirstFrame = nullptr;
     psd->mLastFrame = nullptr;
   }
   else {
     PerFrameData* prevFrame = pfd->mPrev;
     prevFrame->mNext = nullptr;
     psd->mLastFrame = prevFrame;
   }
   // Now free it, and if it has a span, free that too
   pfd->mNext = mFrameFreeList;
   mFrameFreeList = pfd;
 #ifdef DEBUG
   mFramesFreed++;
 #endif
   if (nullptr != pfd->mSpan) {
     FreeSpan(pfd->mSpan);
   }
 #ifdef NOISY_PUSHING
   nsFrame::IndentBy(stdout, mSpanDepth);
   printf("PushFrame: %p after:\n", psd);
   DumpPerSpanData(psd, 1);
 #endif
 }
 void
 nsLineLayout::FreeSpan(PerSpanData* psd)
 {
   // Free its frames
   PerFrameData* pfd = psd->mFirstFrame;
   while (nullptr != pfd) {
     if (nullptr != pfd->mSpan) {
       FreeSpan(pfd->mSpan);
     }
     PerFrameData* next = pfd->mNext;
     pfd->mNext = mFrameFreeList;
     mFrameFreeList = pfd;
 #ifdef DEBUG
     mFramesFreed++;
 #endif
     pfd = next;
   }
   // Now put the span on the free list since it's free too
   psd->mNextFreeSpan = mSpanFreeList;
   mSpanFreeList = psd;
 #ifdef DEBUG
   mSpansFreed++;
 #endif
 }
 bool
 nsLineLayout::IsZeroBSize()
 {
   PerSpanData* psd = mCurrentSpan;
   PerFrameData* pfd = psd->mFirstFrame;
   while (nullptr != pfd) {
     if (0 != pfd->mBounds.BSize(psd->mWritingMode)) {
       return false;
     }
     pfd = pfd->mNext;
   }
   return true;
 }
 nsLineLayout::PerFrameData*
 nsLineLayout::NewPerFrameData(nsIFrame* aFrame)
 {
   PerFrameData* pfd = mFrameFreeList;
   if (!pfd) {
     void *mem;
     PL_ARENA_ALLOCATE(mem, &mArena, sizeof(PerFrameData));
     if (!mem) {
       NS_RUNTIMEABORT("OOM");
     }
     pfd = reinterpret_cast<PerFrameData*>(mem);
   }
   else {
     mFrameFreeList = pfd->mNext;
   }
   pfd->mSpan = nullptr;
   pfd->mNext = nullptr;
   pfd->mPrev = nullptr;
   pfd->mFlags = 0;  // all flags default to false
   pfd->mFrame = aFrame;
   WritingMode frameWM = aFrame->GetWritingMode();
   WritingMode lineWM = mRootSpan->mWritingMode;
   pfd->mBounds = LogicalRect(lineWM);
   pfd->mMargin = LogicalMargin(frameWM);
   pfd->mBorderPadding = LogicalMargin(frameWM);
   pfd->mOffsets = LogicalMargin(frameWM);
 #ifdef DEBUG
   pfd->mBlockDirAlign = 0xFF;
   mFramesAllocated++;
 #endif
   return pfd;
 }
 bool
 nsLineLayout::LineIsBreakable() const
 {
   // XXX mTotalPlacedFrames should go away and we should just use
   // mLineIsEmpty here instead
   if ((0 != mTotalPlacedFrames) || mImpactedByFloats) {
     return true;
   }
   return false;
 }
 // Checks all four sides for percentage units.  This means it should
 // only be used for things (margin, padding) where percentages on top
 // and bottom depend on the *width* just like percentages on left and
 // right.
 static bool
 HasPercentageUnitSide(const nsStyleSides& aSides)
 {
   NS_FOR_CSS_SIDES(side) {
     if (aSides.Get(side).HasPercent())
       return true;
   }
   return false;
 }
 static bool
 IsPercentageAware(const nsIFrame* aFrame)
 {
   NS_ASSERTION(aFrame, "null frame is not allowed");
   nsIAtom *fType = aFrame->GetType();
   if (fType == nsGkAtoms::textFrame) {
     // None of these things can ever be true for text frames.
     return false;
   }
   // Some of these things don't apply to non-replaced inline frames
   // (that is, fType == nsGkAtoms::inlineFrame), but we won't bother making
   // things unnecessarily complicated, since they'll probably be set
   // quite rarely.
   const nsStyleMargin* margin = aFrame->StyleMargin();
   if (HasPercentageUnitSide(margin->mMargin)) {
     return true;
   }
   const nsStylePadding* padding = aFrame->StylePadding();
   if (HasPercentageUnitSide(padding->mPadding)) {
     return true;
   }
   // Note that borders can't be aware of percentages
   const nsStylePosition* pos = aFrame->StylePosition();
   if ((pos->WidthDependsOnContainer() &&
        pos->mWidth.GetUnit() != eStyleUnit_Auto) ||
       pos->MaxWidthDependsOnContainer() ||
       pos->MinWidthDependsOnContainer() ||
       pos->OffsetHasPercent(NS_SIDE_RIGHT) ||
       pos->OffsetHasPercent(NS_SIDE_LEFT)) {
     return true;
   }
   if (eStyleUnit_Auto == pos->mWidth.GetUnit()) {
     // We need to check for frames that shrink-wrap when they're auto
     // width.
     const nsStyleDisplay* disp = aFrame->StyleDisplay();
     if (disp->mDisplay == NS_STYLE_DISPLAY_INLINE_BLOCK ||
         disp->mDisplay == NS_STYLE_DISPLAY_INLINE_TABLE ||
         fType == nsGkAtoms::HTMLButtonControlFrame ||
         fType == nsGkAtoms::gfxButtonControlFrame ||
         fType == nsGkAtoms::fieldSetFrame ||
         fType == nsGkAtoms::comboboxDisplayFrame) {
       return true;
     }
     // Per CSS 2.1, section 10.3.2:
     //   If 'height' and 'width' both have computed values of 'auto' and
     //   the element has an intrinsic ratio but no intrinsic height or
     //   width and the containing block's width does not itself depend
     //   on the replaced element's width, then the used value of 'width'
     //   is calculated from the constraint equation used for
     //   block-level, non-replaced elements in normal flow.
     nsIFrame *f = const_cast<nsIFrame*>(aFrame);
     if (f->GetIntrinsicRatio() != nsSize(0, 0) &&
         // Some percents are treated like 'auto', so check != coord
         pos->mHeight.GetUnit() != eStyleUnit_Coord) {
       const IntrinsicSize &intrinsicSize = f->GetIntrinsicSize();
       if (intrinsicSize.width.GetUnit() == eStyleUnit_None &&
           intrinsicSize.height.GetUnit() == eStyleUnit_None) {
         return true;
       }
     }
   }
   return false;
 }
 nsresult
 nsLineLayout::ReflowFrame(nsIFrame* aFrame,
                           nsReflowStatus& aReflowStatus,
                           nsHTMLReflowMetrics* aMetrics,
                           bool& aPushedFrame)
 {
   // Initialize OUT parameter
   aPushedFrame = false;
   PerFrameData* pfd = NewPerFrameData(aFrame);
   PerSpanData* psd = mCurrentSpan;
   psd->AppendFrame(pfd);
 #ifdef REALLY_NOISY_REFLOW
   nsFrame::IndentBy(stdout, mSpanDepth);
   printf("%p: Begin ReflowFrame pfd=%p ", psd, pfd);
   nsFrame::ListTag(stdout, aFrame);
   printf("\n");
 #endif
   mTextJustificationNumSpaces = 0;
   mTextJustificationNumLetters = 0;
   // Stash copies of some of the computed state away for later
   // (block-direction alignment, for example)
   WritingMode frameWM = aFrame->GetWritingMode();
   WritingMode lineWM = mRootSpan->mWritingMode;
   // NOTE: While the x coordinate remains relative to the parent span,
   // the y coordinate is fixed at the top edge for the line. During
   // BlockDirAlignFrames we will repair this so that the y coordinate
   // is properly set and relative to the appropriate span.
   pfd->mBounds.IStart(lineWM) = psd->mICoord;
   pfd->mBounds.BStart(lineWM) = mBStartEdge;
   // We want to guarantee that we always make progress when
   // formatting. Therefore, if the object being placed on the line is
   // too big for the line, but it is the only thing on the line and is not
   // impacted by a float, then we go ahead and place it anyway. (If the line
   // is impacted by one or more floats, then it is safe to break because
   // we can move the line down below float(s).)
   //
   // Capture this state *before* we reflow the frame in case it clears
   // the state out. We need to know how to treat the current frame
   // when breaking.
   bool notSafeToBreak = LineIsEmpty() && !mImpactedByFloats;
   // Figure out whether we're talking about a textframe here
   nsIAtom* frameType = aFrame->GetType();
   bool isText = frameType == nsGkAtoms::textFrame;
   // Compute the available size for the frame. This available width
   // includes room for the side margins.
   // For now, set the available height to unconstrained always.
   nsSize availSize(mBlockReflowState->ComputedWidth(), NS_UNCONSTRAINEDSIZE);
   // Inline-ish and text-ish things don't compute their width;
   // everything else does.  We need to give them an available width that
   // reflects the space left on the line.
   NS_WARN_IF_FALSE(psd->mIEnd != NS_UNCONSTRAINEDSIZE,
                    "have unconstrained width; this should only result from "
                    "very large sizes, not attempts at intrinsic width "
                    "calculation");
   nscoord availableSpaceOnLine = psd->mIEnd - psd->mICoord;
   // Setup reflow state for reflowing the frame
   Maybe<nsHTMLReflowState> reflowStateHolder;
   if (!isText) {
     reflowStateHolder.construct(mPresContext, *psd->mReflowState,
                                 aFrame, availSize);
     nsHTMLReflowState& reflowState = reflowStateHolder.ref();
     reflowState.mLineLayout = this;
     reflowState.mFlags.mIsTopOfPage = mIsTopOfPage;
     if (reflowState.ComputedWidth() == NS_UNCONSTRAINEDSIZE)
       reflowState.AvailableWidth() = availableSpaceOnLine;
     WritingMode stateWM = reflowState.GetWritingMode();
     pfd->mMargin =
       reflowState.ComputedLogicalMargin().ConvertTo(frameWM, stateWM);
     pfd->mBorderPadding =
       reflowState.ComputedLogicalBorderPadding().ConvertTo(frameWM, stateWM);
     pfd->SetFlag(PFD_RELATIVEPOS,
                  reflowState.mStyleDisplay->IsRelativelyPositionedStyle());
     if (pfd->GetFlag(PFD_RELATIVEPOS)) {
       pfd->mOffsets =
         reflowState.ComputedLogicalOffsets().ConvertTo(frameWM, stateWM);
     }
     // Calculate whether the the frame should have a start margin and
     // subtract the margin from the available width if necessary.
     // The margin will be applied to the starting inline coordinates of
     // the frame in CanPlaceFrame() after reflowing the frame.
     AllowForStartMargin(pfd, reflowState);
   }
   // if isText(), no need to propagate NS_FRAME_IS_DIRTY from the parent,
   // because reflow doesn't look at the dirty bits on the frame being reflowed.
   // See if this frame depends on the width of its containing block.  If
   // so, disable resize reflow optimizations for the line.  (Note that,
   // to be conservative, we do this if we *try* to fit a frame on a
   // line, even if we don't succeed.)  (Note also that we can only make
   // this IsPercentageAware check *after* we've constructed our
   // nsHTMLReflowState, because that construction may be what forces aFrame
   // to lazily initialize its (possibly-percent-valued) intrinsic size.)
   if (mGotLineBox && IsPercentageAware(aFrame)) {
     mLineBox->DisableResizeReflowOptimization();
   }
   // Let frame know that are reflowing it. Note that we don't bother
   // positioning the frame yet, because we're probably going to end up
   // moving it when we do the block-direction alignment
   aFrame->WillReflow(mPresContext);
   // Adjust spacemanager coordinate system for the frame.
   nsHTMLReflowMetrics metrics(lineWM);
 #ifdef DEBUG
   metrics.Width() = nscoord(0xdeadbeef);
   metrics.Height() = nscoord(0xdeadbeef);
 #endif
   nsRect physicalBounds = pfd->mBounds.GetPhysicalRect(lineWM, mContainerWidth);
   nscoord tx = physicalBounds.x;
   nscoord ty = physicalBounds.y;
   mFloatManager->Translate(tx, ty);
   int32_t savedOptionalBreakOffset;
   gfxBreakPriority savedOptionalBreakPriority;
   nsIContent* savedOptionalBreakContent =
     GetLastOptionalBreakPosition(&savedOptionalBreakOffset,
                                  &savedOptionalBreakPriority);
   if (!isText) {
     nsresult rv = aFrame->Reflow(mPresContext, metrics, reflowStateHolder.ref(),
                                  aReflowStatus);
     if (NS_FAILED(rv)) {
       NS_WARNING( "Reflow of frame failed in nsLineLayout" );
       return rv;
     }
   } else {
     static_cast<nsTextFrame*>(aFrame)->
       ReflowText(*this, availableSpaceOnLine, psd->mReflowState->rendContext,
                  metrics, aReflowStatus);
   }
   pfd->mJustificationNumSpaces = mTextJustificationNumSpaces;
   pfd->mJustificationNumLetters = mTextJustificationNumLetters;
   // See if the frame is a placeholderFrame and if it is process
   // the float. At the same time, check if the frame has any non-collapsed-away
   // content.
   bool placedFloat = false;
   bool isEmpty;
   if (!frameType) {
     isEmpty = pfd->mFrame->IsEmpty();
   } else {
     if (nsGkAtoms::placeholderFrame == frameType) {
       isEmpty = true;
       pfd->SetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE, true);
       nsIFrame* outOfFlowFrame = nsLayoutUtils::GetFloatFromPlaceholder(aFrame);
       if (outOfFlowFrame) {
         // Add mTrimmableWidth to the available width since if the line ends
         // here, the width of the inline content will be reduced by
         // mTrimmableWidth.
         nscoord availableWidth = psd->mIEnd - (psd->mICoord - mTrimmableWidth);
         if (psd->mNoWrap) {
           // If we place floats after inline content where there's
           // no break opportunity, we don't know how much additional
           // width is required for the non-breaking content after the float,
           // so we can't know whether the float plus that content will fit
           // on the line. So for now, don't place floats after inline
           // content where there's no break opportunity. This is incorrect
           // but hopefully rare. Fixing it will require significant
           // restructuring of line layout.
           // We might as well allow zero-width floats to be placed, though.
           availableWidth = 0;
         }
         placedFloat = AddFloat(outOfFlowFrame, availableWidth);
         NS_ASSERTION(!(outOfFlowFrame->GetType() == nsGkAtoms::letterFrame &&
                        GetFirstLetterStyleOK()),
                     "FirstLetterStyle set on line with floating first letter");
       }
     }
     else if (isText) {
       // Note non-empty text-frames for inline frame compatibility hackery
       pfd->SetFlag(PFD_ISTEXTFRAME, true);
       nsTextFrame* textFrame = static_cast<nsTextFrame*>(pfd->mFrame);
       isEmpty = !textFrame->HasNoncollapsedCharacters();
       if (!isEmpty) {
         pfd->SetFlag(PFD_ISNONEMPTYTEXTFRAME, true);
         nsIContent* content = textFrame->GetContent();
         const nsTextFragment* frag = content->GetText();
         if (frag) {
           pfd->SetFlag(PFD_ISNONWHITESPACETEXTFRAME,
                        !content->TextIsOnlyWhitespace());
         }
       }
     }
     else if (nsGkAtoms::brFrame == frameType) {
       pfd->SetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE, true);
       isEmpty = false;
     } else {
       if (nsGkAtoms::letterFrame==frameType) {
         pfd->SetFlag(PFD_ISLETTERFRAME, true);
       }
       if (pfd->mSpan) {
         isEmpty = !pfd->mSpan->mHasNonemptyContent && pfd->mFrame->IsSelfEmpty();
       } else {
         isEmpty = pfd->mFrame->IsEmpty();
       }
     }
   }
   mFloatManager->Translate(-tx, -ty);
   NS_ASSERTION(metrics.Width() >= 0, "bad width");
   NS_ASSERTION(metrics.Height() >= 0,"bad height");
   if (metrics.Width() < 0) metrics.Width() = 0;
   if (metrics.Height() < 0) metrics.Height() = 0;
 #ifdef DEBUG
   // Note: break-before means ignore the reflow metrics since the
   // frame will be reflowed another time.
   if (!NS_INLINE_IS_BREAK_BEFORE(aReflowStatus)) {
     if (CRAZY_SIZE(metrics.Width()) || CRAZY_SIZE(metrics.Height())) {
       printf("nsLineLayout: ");
       nsFrame::ListTag(stdout, aFrame);
       printf(" metrics=%d,%d!\n", metrics.Width(), metrics.Height());
     }
     if ((metrics.Width() == nscoord(0xdeadbeef)) ||
         (metrics.Height() == nscoord(0xdeadbeef))) {
       printf("nsLineLayout: ");
       nsFrame::ListTag(stdout, aFrame);
       printf(" didn't set w/h %d,%d!\n", metrics.Width(), metrics.Height());
     }
   }
 #endif
   // Unlike with non-inline reflow, the overflow area here does *not*
   // include the accumulation of the frame's bounds and its inline
   // descendants' bounds. Nor does it include the outline area; it's
   // just the union of the bounds of any absolute children. That is
   // added in later by nsLineLayout::ReflowInlineFrames.
   pfd->mOverflowAreas = metrics.mOverflowAreas;
   pfd->mBounds.ISize(lineWM) = metrics.ISize();
   pfd->mBounds.BSize(lineWM) = metrics.BSize();
   // Size the frame, but |RelativePositionFrames| will size the view.
   aFrame->SetSize(nsSize(metrics.Width(), metrics.Height()));
   // Tell the frame that we're done reflowing it
   aFrame->DidReflow(mPresContext,
                     isText ? nullptr : reflowStateHolder.addr(),
                     nsDidReflowStatus::FINISHED);
   if (aMetrics) {
     *aMetrics = metrics;
   }
   if (!NS_INLINE_IS_BREAK_BEFORE(aReflowStatus)) {
     // If frame is complete and has a next-in-flow, we need to delete
     // them now. Do not do this when a break-before is signaled because
     // the frame is going to get reflowed again (and may end up wanting
     // a next-in-flow where it ends up).
     if (NS_FRAME_IS_COMPLETE(aReflowStatus)) {
       nsIFrame* kidNextInFlow = aFrame->GetNextInFlow();
       if (nullptr != kidNextInFlow) {
         // Remove all of the childs next-in-flows. Make sure that we ask
         // the right parent to do the removal (it's possible that the
         // parent is not this because we are executing pullup code)
         nsContainerFrame* parent = static_cast<nsContainerFrame*>
                                                   (kidNextInFlow->GetParent());
         parent->DeleteNextInFlowChild(kidNextInFlow, true);
       }
     }
     // Check whether this frame breaks up text runs. All frames break up text
     // runs (hence return false here) except for text frames and inline containers.
     bool continuingTextRun = aFrame->CanContinueTextRun();
     // Clear any residual mTrimmableWidth if this isn't a text frame
     if (!continuingTextRun && !pfd->GetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE)) {
       mTrimmableWidth = 0;
     }
     // See if we can place the frame. If we can't fit it, then we
     // return now.
     bool optionalBreakAfterFits;
     NS_ASSERTION(isText ||
                  !reflowStateHolder.ref().IsFloating(),
                  "How'd we get a floated inline frame? "
                  "The frame ctor should've dealt with this.");
     if (CanPlaceFrame(pfd, notSafeToBreak, continuingTextRun,
                       savedOptionalBreakContent != nullptr, metrics,
                       aReflowStatus, &optionalBreakAfterFits)) {
       if (!isEmpty) {
         psd->mHasNonemptyContent = true;
         mLineIsEmpty = false;
         if (!pfd->mSpan) {
           // nonempty leaf content has been placed
           mLineAtStart = false;
         }
       }
       // Place the frame, updating aBounds with the final size and
       // location.  Then apply the bottom+right margins (as
       // appropriate) to the frame.
       PlaceFrame(pfd, metrics);
       PerSpanData* span = pfd->mSpan;
       if (span) {
         // The frame we just finished reflowing is an inline
         // container.  It needs its child frames aligned in the block direction,
         // so do most of it now.
         BlockDirAlignFrames(span);
       }
       if (!continuingTextRun) {
         if (!psd->mNoWrap && (!LineIsEmpty() || placedFloat)) {
           // record soft break opportunity after this content that can't be
           // part of a text run. This is not a text frame so we know
           // that offset INT32_MAX means "after the content".
           if (NotifyOptionalBreakPosition(aFrame->GetContent(), INT32_MAX, optionalBreakAfterFits, gfxBreakPriority::eNormalBreak)) {
             // If this returns true then we are being told to actually break here.
             aReflowStatus = NS_INLINE_LINE_BREAK_AFTER(aReflowStatus);
           }
         }
       }
     }
     else {
       PushFrame(aFrame);
       aPushedFrame = true;
       // Undo any saved break positions that the frame might have told us about,
       // since we didn't end up placing it
       RestoreSavedBreakPosition(savedOptionalBreakContent,
                                 savedOptionalBreakOffset,
                                 savedOptionalBreakPriority);
     }
   }
   else {
     PushFrame(aFrame);
   }
 #ifdef REALLY_NOISY_REFLOW
   nsFrame::IndentBy(stdout, mSpanDepth);
   printf("End ReflowFrame ");
   nsFrame::ListTag(stdout, aFrame);
   printf(" status=%x\n", aReflowStatus);
 #endif
   return NS_OK;
 }
 void
 nsLineLayout::AllowForStartMargin(PerFrameData* pfd,
                                   nsHTMLReflowState& aReflowState)
 {
   NS_ASSERTION(!aReflowState.IsFloating(),
                "How'd we get a floated inline frame? "
                "The frame ctor should've dealt with this.");
   WritingMode frameWM = pfd->mFrame->GetWritingMode();
   // Only apply start-margin on the first-in flow for inline frames,
   // and make sure to not apply it to any inline other than the first
   // in an ib split.  Note that the ib sibling (block-in-inline
   // sibling) annotations only live on the first continuation, but we
   // don't want to apply the start margin for later continuations
   // anyway.
   if (pfd->mFrame->GetPrevContinuation() ||
       pfd->mFrame->FrameIsNonFirstInIBSplit()) {
     // Zero this out so that when we compute the max-element-width of
     // the frame we will properly avoid adding in the starting margin.
     pfd->mMargin.IStart(frameWM) = 0;
   } else {
     NS_WARN_IF_FALSE(NS_UNCONSTRAINEDSIZE != aReflowState.AvailableWidth(),
                      "have unconstrained width; this should only result from "
                      "very large sizes, not attempts at intrinsic width "
                      "calculation");
     if (NS_UNCONSTRAINEDSIZE == aReflowState.ComputedWidth()) {
       // For inline-ish and text-ish things (which don't compute widths
       // in the reflow state), adjust available width to account for the
       // start margin. The end margin will be accounted for when we
       // finish flowing the frame.
       aReflowState.AvailableWidth() -= pfd->mMargin.IStart(frameWM);
     }
   }
 }
 nscoord
 nsLineLayout::GetCurrentFrameInlineDistanceFromBlock()
 {
   PerSpanData* psd;
   nscoord x = 0;
   for (psd = mCurrentSpan; psd; psd = psd->mParent) {
     x += psd->mICoord;
   }
   return x;
 }
 /**
  * See if the frame can be placed now that we know it's desired size.
  * We can always place the frame if the line is empty. Note that we
  * know that the reflow-status is not a break-before because if it was
  * ReflowFrame above would have returned false, preventing this method
  * from being called. The logic in this method assumes that.
  *
  * Note that there is no check against the Y coordinate because we
  * assume that the caller will take care of that.
  */
 bool
 nsLineLayout::CanPlaceFrame(PerFrameData* pfd,
                             bool aNotSafeToBreak,
                             bool aFrameCanContinueTextRun,
                             bool aCanRollBackBeforeFrame,
                             nsHTMLReflowMetrics& aMetrics,
                             nsReflowStatus& aStatus,
                             bool* aOptionalBreakAfterFits)
 {
   NS_PRECONDITION(pfd && pfd->mFrame, "bad args, null pointers for frame data");
   *aOptionalBreakAfterFits = true;
   WritingMode frameWM = pfd->mFrame->GetWritingMode();
   WritingMode lineWM = mRootSpan->mWritingMode;
   /*
    * We want to only apply the end margin if we're the last continuation and
    * either not in an {ib} split or the last inline in it.  In all other
    * cases we want to zero it out.  That means zeroing it out if any of these
    * conditions hold:
    * 1) The frame is not complete (in this case it will get a next-in-flow)
    * 2) The frame is complete but has a non-fluid continuation on its
    *    continuation chain.  Note that if it has a fluid continuation, that
    *    continuation will get destroyed later, so we don't want to drop the
    *    end-margin in that case.
    * 3) The frame is in an {ib} split and is not the last part.
    *
    * However, none of that applies if this is a letter frame (XXXbz why?)
    */
   if ((NS_FRAME_IS_NOT_COMPLETE(aStatus) ||
        pfd->mFrame->LastInFlow()->GetNextContinuation() ||
        pfd->mFrame->FrameIsNonLastInIBSplit())
       && !pfd->GetFlag(PFD_ISLETTERFRAME)) {
     pfd->mMargin.IEnd(frameWM) = 0;
   }
   // Convert the frame's margins to the line's writing mode and apply
   // the start margin to the frame bounds.
   LogicalMargin usedMargins = pfd->mMargin.ConvertTo(lineWM, frameWM);
   nscoord startMargin = usedMargins.IStart(lineWM);
   nscoord endMargin = usedMargins.IEnd(lineWM);
   pfd->mBounds.IStart(lineWM) += startMargin;
   PerSpanData* psd = mCurrentSpan;
   if (psd->mNoWrap) {
     // When wrapping is off, everything fits.
     return true;
   }
 #ifdef NOISY_CAN_PLACE_FRAME
   if (nullptr != psd->mFrame) {
     nsFrame::ListTag(stdout, psd->mFrame->mFrame);
   }
   else {
     nsFrame::ListTag(stdout, mBlockReflowState->frame);
   }
   printf(": aNotSafeToBreak=%s frame=", aNotSafeToBreak ? "true" : "false");
   nsFrame::ListTag(stdout, pfd->mFrame);
   printf(" frameWidth=%d, margins=%d,%d\n",
          pfd->mBounds.IEnd(lineWM) + endMargin - psd->mICoord,
          startMargin, endMargin);
 #endif
   // Set outside to true if the result of the reflow leads to the
   // frame sticking outside of our available area.
   bool outside = pfd->mBounds.IEnd(lineWM) - mTrimmableWidth + endMargin >
                  psd->mIEnd;
   if (!outside) {
     // If it fits, it fits
 #ifdef NOISY_CAN_PLACE_FRAME
     printf("   ==> inside\n");
 #endif
     return true;
   }
   *aOptionalBreakAfterFits = false;
   // When it doesn't fit, check for a few special conditions where we
   // allow it to fit anyway.
   if (0 == startMargin + pfd->mBounds.ISize(lineWM) + endMargin) {
     // Empty frames always fit right where they are
 #ifdef NOISY_CAN_PLACE_FRAME
     printf("   ==> empty frame fits\n");
 #endif
     return true;
   }
 #ifdef FIX_BUG_50257
   // another special case:  always place a BR
   if (nsGkAtoms::brFrame == pfd->mFrame->GetType()) {
 #ifdef NOISY_CAN_PLACE_FRAME
     printf("   ==> BR frame fits\n");
 #endif
     return true;
   }
 #endif
   if (aNotSafeToBreak) {
     // There are no frames on the line that take up width and the line is
     // not impacted by floats, so we must allow the current frame to be
     // placed on the line
 #ifdef NOISY_CAN_PLACE_FRAME
     printf("   ==> not-safe and not-impacted fits: ");
     while (nullptr != psd) {
       printf("<psd=%p x=%d left=%d> ", psd, psd->mICoord, psd->mIStart);
       psd = psd->mParent;
     }
     printf("\n");
 #endif
     return true;
   }
   // Special check for span frames
   if (pfd->mSpan && pfd->mSpan->mContainsFloat) {
     // If the span either directly or indirectly contains a float then
     // it fits. Why? It's kind of complicated, but here goes:
     //
     // 1. CanPlaceFrame is used for all frame placements on a line,
     // and in a span. This includes recursively placement of frames
     // inside of spans, and the span itself. Because the logic always
     // checks for room before proceeding (the code above here), the
     // only things on a line will be those things that "fit".
     //
     // 2. Before a float is placed on a line, the line has to be empty
     // (otherwise it's a "below current line" float and will be placed
     // after the line).
     //
     // Therefore, if the span directly or indirectly has a float
     // then it means that at the time of the placement of the float
     // the line was empty. Because of #1, only the frames that fit can
     // be added after that point, therefore we can assume that the
     // current span being placed has fit.
     //
     // So how do we get here and have a span that should already fit
     // and yet doesn't: Simple: span's that have the no-wrap attribute
     // set on them and contain a float and are placed where they
     // don't naturally fit.
     return true;
  }
   if (aFrameCanContinueTextRun) {
     // Let it fit, but we reserve the right to roll back.
     // Note that we usually won't get here because a text frame will break
     // itself to avoid exceeding the available width.
     // We'll only get here for text frames that couldn't break early enough.
 #ifdef NOISY_CAN_PLACE_FRAME
     printf("   ==> placing overflowing textrun, requesting backup\n");
 #endif
     // We will want to try backup.
     mNeedBackup = true;
     return true;
   }
 #ifdef NOISY_CAN_PLACE_FRAME
   printf("   ==> didn't fit\n");
 #endif
   aStatus = NS_INLINE_LINE_BREAK_BEFORE();
   return false;
 }
 /**
  * Place the frame. Update running counters.
  */
 void
 nsLineLayout::PlaceFrame(PerFrameData* pfd, nsHTMLReflowMetrics& aMetrics)
 {
   // Record ascent and update max-ascent and max-descent values
   if (aMetrics.TopAscent() == nsHTMLReflowMetrics::ASK_FOR_BASELINE)
     pfd->mAscent = pfd->mFrame->GetBaseline();
   else
     pfd->mAscent = aMetrics.TopAscent();
   // Advance to next inline coordinate
   WritingMode frameWM = pfd->mFrame->GetWritingMode();
   WritingMode lineWM = mRootSpan->mWritingMode;
   mCurrentSpan->mICoord = pfd->mBounds.IEnd(lineWM) +
                           pfd->mMargin.ConvertTo(lineWM, frameWM).IEnd(lineWM);
   // Count the number of non-placeholder frames on the line...
   if (pfd->mFrame->GetType() == nsGkAtoms::placeholderFrame) {
     NS_ASSERTION(pfd->mBounds.ISize(lineWM) == 0 &&
                  pfd->mBounds.BSize(lineWM) == 0,
                  "placeholders should have 0 width/height (checking "
                  "placeholders were never counted by the old code in "
                  "this function)");
   } else {
     mTotalPlacedFrames++;
   }
 }
 void
 nsLineLayout::AddBulletFrame(nsIFrame* aFrame,
                              const nsHTMLReflowMetrics& aMetrics)
 {
   NS_ASSERTION(mCurrentSpan == mRootSpan, "bad linelayout user");
   NS_ASSERTION(mGotLineBox, "must have line box");
   nsIFrame *blockFrame = mBlockReflowState->frame;
   NS_ASSERTION(blockFrame->IsFrameOfType(nsIFrame::eBlockFrame),
                "must be for block");
   if (!static_cast<nsBlockFrame*>(blockFrame)->BulletIsEmpty()) {
     mHasBullet = true;
     mLineBox->SetHasBullet();
   }
   PerFrameData* pfd = NewPerFrameData(aFrame);
   mRootSpan->AppendFrame(pfd);
   pfd->SetFlag(PFD_ISBULLET, true);
   if (aMetrics.TopAscent() == nsHTMLReflowMetrics::ASK_FOR_BASELINE)
     pfd->mAscent = aFrame->GetBaseline();
   else
     pfd->mAscent = aMetrics.TopAscent();
   // Note: block-coord value will be updated during block-direction alignment
   pfd->mBounds = LogicalRect(mRootSpan->mWritingMode,
                              aFrame->GetRect(), mContainerWidth);
   pfd->mOverflowAreas = aMetrics.mOverflowAreas;
 }
 #ifdef DEBUG
 void
 nsLineLayout::DumpPerSpanData(PerSpanData* psd, int32_t aIndent)
 {
   nsFrame::IndentBy(stdout, aIndent);
   printf("%p: left=%d x=%d right=%d\n", static_cast<void*>(psd),
          psd->mIStart, psd->mICoord, psd->mIEnd);
   PerFrameData* pfd = psd->mFirstFrame;
   while (nullptr != pfd) {
     nsFrame::IndentBy(stdout, aIndent+1);
     nsFrame::ListTag(stdout, pfd->mFrame);
     nsRect rect = pfd->mBounds.GetPhysicalRect(psd->mWritingMode,
                                                mContainerWidth);
     printf(" %d,%d,%d,%d\n", rect.x, rect.y, rect.width, rect.height);
     if (pfd->mSpan) {
       DumpPerSpanData(pfd->mSpan, aIndent + 1);
     }
     pfd = pfd->mNext;
   }
 }
 #endif
 #define VALIGN_OTHER  0
 #define VALIGN_TOP    1
 #define VALIGN_BOTTOM 2
 void
 nsLineLayout::BlockDirAlignLine()
 {
   // Synthesize a PerFrameData for the block frame
   PerFrameData rootPFD(mBlockReflowState->frame->GetWritingMode());
   rootPFD.mFrame = mBlockReflowState->frame;
   rootPFD.mAscent = 0;
   mRootSpan->mFrame = &rootPFD;
   // Partially place the children of the block frame. The baseline for
   // this operation is set to zero so that the y coordinates for all
   // of the placed children will be relative to there.
   PerSpanData* psd = mRootSpan;
   BlockDirAlignFrames(psd);
   // *** Note that comments here still use the anachronistic term "line-height"
   // when we really mean "size of the line in the block direction". This is
   // partly for brevity and partly to retain the association with the CSS
   // line-height property
   //
   // Compute the line-height. The line-height will be the larger of:
   //
   // [1] maxBCoord - minBCoord (the distance between the first child's
   // block-start edge and the last child's block-end edge)
   //
   // [2] the maximum logical box block size (since not every frame may have
   // participated in #1; for example: block-start/end aligned frames)
   //
   // [3] the minimum line height ("line-height" property set on the
   // block frame)
   nscoord lineBSize = psd->mMaxBCoord - psd->mMinBCoord;
   // Now that the line-height is computed, we need to know where the
   // baseline is in the line. Position baseline so that mMinBCoord is just
   // inside the start of the line box.
   nscoord baselineBCoord;
   if (psd->mMinBCoord < 0) {
     baselineBCoord = mBStartEdge - psd->mMinBCoord;
   }
   else {
     baselineBCoord = mBStartEdge;
   }
   // It's also possible that the line block-size isn't tall enough because
   // of block start/end aligned elements that were not accounted for in
   // min/max BCoord.
   //
   // The CSS2 spec doesn't really say what happens when to the
   // baseline in this situations. What we do is if the largest start
   // aligned box block size is greater than the line block-size then we leave
   // the baseline alone. If the largest end aligned box is greater
   // than the line block-size then we slide the baseline forward by the extra
   // amount.
   //
   // Navigator 4 gives precedence to the first top/bottom aligned
   // object.  We just let block end aligned objects win.
   if (lineBSize < mMaxEndBoxBSize) {
     // When the line is shorter than the maximum block start aligned box
     nscoord extra = mMaxEndBoxBSize - lineBSize;
     baselineBCoord += extra;
     lineBSize = mMaxEndBoxBSize;
   }
   if (lineBSize < mMaxStartBoxBSize) {
     lineBSize = mMaxStartBoxBSize;
   }
 #ifdef NOISY_BLOCKDIR_ALIGN
   printf("  [line]==> lineBSize=%d baselineBCoord=%d\n", lineBSize, baselineBCoord);
 #endif
   // Now position all of the frames in the root span. We will also
   // recurse over the child spans and place any block start/end aligned
   // frames we find.
   // XXX PERFORMANCE: set a bit per-span to avoid the extra work
   // (propagate it upward too)
   WritingMode lineWM = psd->mWritingMode;
   for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
     if (pfd->mBlockDirAlign == VALIGN_OTHER) {
       pfd->mBounds.BStart(lineWM) += baselineBCoord;
       pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
     }
   }
   PlaceStartEndFrames(psd, -mBStartEdge, lineBSize);
   // If the frame being reflowed has text decorations, we simulate the
   // propagation of those decorations to a line-level element by storing the
   // offset in a frame property on any child frames that are aligned in the
   // block direction somewhere other than the baseline. This property is then
   // used by nsTextFrame::GetTextDecorations when the same conditions are met.
   if (rootPFD.mFrame->StyleContext()->HasTextDecorationLines()) {
     for (const PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
       const nsIFrame *const f = pfd->mFrame;
       if (f->VerticalAlignEnum() != NS_STYLE_VERTICAL_ALIGN_BASELINE) {
         const nscoord offset = baselineBCoord - pfd->mBounds.BStart(lineWM);
         f->Properties().Set(nsIFrame::LineBaselineOffset(),
                             NS_INT32_TO_PTR(offset));
       }
     }
   }
   // Fill in returned line-box and max-element-width data
   mLineBox->SetBounds(lineWM,
                       psd->mIStart, mBStartEdge,
                       psd->mICoord - psd->mIStart, lineBSize,
                       mContainerWidth);
   mFinalLineBSize = lineBSize;
   mLineBox->SetAscent(baselineBCoord - mBStartEdge);
 #ifdef NOISY_BLOCKDIR_ALIGN
   printf(
     "  [line]==> bounds{x,y,w,h}={%d,%d,%d,%d} lh=%d a=%d\n",
     mLineBox->mBounds.IStart(lineWM), mLineBox->mBounds.BStart(lineWM),
     mLineBox->mBounds.ISize(lineWM), mLineBox->mBounds.BSize(lineWM),
     mFinalLineBSize, mLineBox->GetAscent());
 #endif
   // Undo root-span mFrame pointer to prevent brane damage later on...
   mRootSpan->mFrame = nullptr;
 }
 void
 nsLineLayout::PlaceStartEndFrames(PerSpanData* psd,
                                   nscoord aDistanceFromStart,
                                   nscoord aLineBSize)
 {
   for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
     PerSpanData* span = pfd->mSpan;
 #ifdef DEBUG
     NS_ASSERTION(0xFF != pfd->mBlockDirAlign, "umr");
 #endif
     WritingMode frameWM = pfd->mFrame->GetWritingMode();
     WritingMode lineWM = mRootSpan->mWritingMode;
     switch (pfd->mBlockDirAlign) {
       case VALIGN_TOP:
         if (span) {
           pfd->mBounds.BStart(lineWM) = -aDistanceFromStart - span->mMinBCoord;
         }
         else {
           pfd->mBounds.BStart(lineWM) =
             -aDistanceFromStart + pfd->mMargin.BStart(frameWM);
         }
         pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("    ");
         nsFrame::ListTag(stdout, pfd->mFrame);
         printf(": y=%d dTop=%d [bp.top=%d topLeading=%d]\n",
                pfd->mBounds.BStart(lineWM), aDistanceFromStart,
                span ? pfd->mBorderPadding.BStart(frameWM) : 0,
                span ? span->mBStartLeading : 0);
 #endif
         break;
       case VALIGN_BOTTOM:
         if (span) {
           // Compute bottom leading
           pfd->mBounds.BStart(lineWM) =
             -aDistanceFromStart + aLineBSize - span->mMaxBCoord;
         }
         else {
           pfd->mBounds.BStart(lineWM) = -aDistanceFromStart + aLineBSize -
             pfd->mMargin.BEnd(frameWM) - pfd->mBounds.BSize(lineWM);
         }
         pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("    ");
         nsFrame::ListTag(stdout, pfd->mFrame);
         printf(": y=%d\n", pfd->mBounds.BStart(lineWM));
 #endif
         break;
     }
     if (span) {
       nscoord fromStart = aDistanceFromStart + pfd->mBounds.BStart(lineWM);
       PlaceStartEndFrames(span, fromStart, aLineBSize);
     }
   }
 }
 static float
 GetInflationForBlockDirAlignment(nsIFrame* aFrame,
                                  nscoord aInflationMinFontSize)
 {
   if (aFrame->IsSVGText()) {
     const nsIFrame* container =
       nsLayoutUtils::GetClosestFrameOfType(aFrame, nsGkAtoms::svgTextFrame);
     NS_ASSERTION(container, "expected to find an ancestor SVGTextFrame");
     return
       static_cast<const SVGTextFrame*>(container)->GetFontSizeScaleFactor();
   }
   return nsLayoutUtils::FontSizeInflationInner(aFrame, aInflationMinFontSize);
 }
 #define BLOCKDIR_ALIGN_FRAMES_NO_MINIMUM nscoord_MAX
 #define BLOCKDIR_ALIGN_FRAMES_NO_MAXIMUM nscoord_MIN
 // Place frames in the block direction within a given span. Note: this doesn't
 // place block start/end aligned frames as those have to wait until the
 // entire line box block size is known. This is called after the span
 // frame has finished being reflowed so that we know its block size.
 void
 nsLineLayout::BlockDirAlignFrames(PerSpanData* psd)
 {
   // Get parent frame info
   PerFrameData* spanFramePFD = psd->mFrame;
   nsIFrame* spanFrame = spanFramePFD->mFrame;
   // Get the parent frame's font for all of the frames in this span
   nsRefPtr<nsFontMetrics> fm;
   float inflation =
     GetInflationForBlockDirAlignment(spanFrame, mInflationMinFontSize);
   nsLayoutUtils::GetFontMetricsForFrame(spanFrame, getter_AddRefs(fm),
                                         inflation);
   mBlockReflowState->rendContext->SetFont(fm);
   bool preMode = mStyleText->WhiteSpaceIsSignificant();
   // See if the span is an empty continuation. It's an empty continuation iff:
   // - it has a prev-in-flow
   // - it has no next in flow
   // - it's zero sized
   WritingMode frameWM = spanFramePFD->mFrame->GetWritingMode();
   WritingMode lineWM = mRootSpan->mWritingMode;
   bool emptyContinuation = psd != mRootSpan &&
     spanFrame->GetPrevInFlow() && !spanFrame->GetNextInFlow() &&
     spanFramePFD->mBounds.IsZeroSize();
 #ifdef NOISY_BLOCKDIR_ALIGN
   printf("[%sSpan]", (psd == mRootSpan)?"Root":"");
   nsFrame::ListTag(stdout, spanFrame);
   printf(": preMode=%s strictMode=%s w/h=%d,%d emptyContinuation=%s",
          preMode ? "yes" : "no",
          mPresContext->CompatibilityMode() != eCompatibility_NavQuirks ? "yes" : "no",
          spanFramePFD->mBounds.ISize(lineWM),
          spanFramePFD->mBounds.BSize(lineWM),
          emptyContinuation ? "yes" : "no");
   if (psd != mRootSpan) {
     WritingMode frameWM = spanFramePFD->mFrame->GetWritingMode();
     printf(" bp=%d,%d,%d,%d margin=%d,%d,%d,%d",
            spanFramePFD->mBorderPadding.Top(frameWM),
            spanFramePFD->mBorderPadding.Right(frameWM),
            spanFramePFD->mBorderPadding.Bottom(frameWM),
            spanFramePFD->mBorderPadding.Left(frameWM),
            spanFramePFD->mMargin.Top(frameWM),
            spanFramePFD->mMargin.Right(frameWM),
            spanFramePFD->mMargin.Bottom(frameWM),
            spanFramePFD->mMargin.Left(frameWM));
   }
   printf("\n");
 #endif
   // Compute the span's mZeroEffectiveSpanBox flag. What we are trying
   // to determine is how we should treat the span: should it act
   // "normally" according to css2 or should it effectively
   // "disappear".
   //
   // In general, if the document being processed is in full standards
   // mode then it should act normally (with one exception). The
   // exception case is when a span is continued and yet the span is
   // empty (e.g. compressed whitespace). For this kind of span we treat
   // it as if it were not there so that it doesn't impact the
   // line block-size.
   //
   // In almost standards mode or quirks mode, we should sometimes make
   // it disappear. The cases that matter are those where the span
   // contains no real text elements that would provide an ascent and
   // descent and height. However, if css style elements have been
   // applied to the span (border/padding/margin) so that it's clear the
   // document author is intending css2 behavior then we act as if strict
   // mode is set.
   //
   // This code works correctly for preMode, because a blank line
   // in PRE mode is encoded as a text node with a LF in it, since
   // text nodes with only whitespace are considered in preMode.
   //
   // Much of this logic is shared with the various implementations of
   // nsIFrame::IsEmpty since they need to duplicate the way it makes
   // some lines empty.  However, nsIFrame::IsEmpty can't be reused here
   // since this code sets zeroEffectiveSpanBox even when there are
   // non-empty children.
   bool zeroEffectiveSpanBox = false;
   // XXXldb If we really have empty continuations, then all these other
   // checks don't make sense for them.
   // XXXldb This should probably just use nsIFrame::IsSelfEmpty, assuming that
   // it agrees with this code.  (If it doesn't agree, it probably should.)
   if ((emptyContinuation ||
        mPresContext->CompatibilityMode() != eCompatibility_FullStandards) &&
       ((psd == mRootSpan) ||
        (spanFramePFD->mBorderPadding.IsEmpty() &&
         spanFramePFD->mMargin.IsEmpty()))) {
     // This code handles an issue with compatibility with non-css
     // conformant browsers. In particular, there are some cases
     // where the font-size and line-height for a span must be
     // ignored and instead the span must *act* as if it were zero
     // sized. In general, if the span contains any non-compressed
     // text then we don't use this logic.
     // However, this is not propagated outwards, since (in compatibility
     // mode) we don't want big line heights for things like
     // <p><font size="-1">Text</font></p>
     // We shouldn't include any whitespace that collapses, unless we're
     // preformatted (in which case it shouldn't, but the width=0 test is
     // perhaps incorrect).  This includes whitespace at the beginning of
     // a line and whitespace preceded (?) by other whitespace.
     // See bug 134580 and bug 155333.
     zeroEffectiveSpanBox = true;
     for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
       if (pfd->GetFlag(PFD_ISTEXTFRAME) &&
           (pfd->GetFlag(PFD_ISNONWHITESPACETEXTFRAME) || preMode ||
            pfd->mBounds.ISize(mRootSpan->mWritingMode) != 0)) {
         zeroEffectiveSpanBox = false;
         break;
       }
     }
   }
   psd->mZeroEffectiveSpanBox = zeroEffectiveSpanBox;
   // Setup baselineBCoord, minBCoord, and maxBCoord
   nscoord baselineBCoord, minBCoord, maxBCoord;
   if (psd == mRootSpan) {
     // Use a zero baselineBCoord since we don't yet know where the baseline
     // will be (until we know how tall the line is; then we will
     // know). In addition, use extreme values for the minBCoord and maxBCoord
     // values so that only the child frames will impact their values
     // (since these are children of the block, there is no span box to
     // provide initial values).
     baselineBCoord = 0;
     minBCoord = BLOCKDIR_ALIGN_FRAMES_NO_MINIMUM;
     maxBCoord = BLOCKDIR_ALIGN_FRAMES_NO_MAXIMUM;
 #ifdef NOISY_BLOCKDIR_ALIGN
     printf("[RootSpan]");
     nsFrame::ListTag(stdout, spanFrame);
     printf(": pass1 valign frames: topEdge=%d minLineBSize=%d zeroEffectiveSpanBox=%s\n",
            mBStartEdge, mMinLineBSize,
            zeroEffectiveSpanBox ? "yes" : "no");
 #endif
   }
   else {
     // Compute the logical block size for this span. The logical block size
     // is based on the "line-height" value, not the font-size. Also
     // compute the top leading.
     float inflation =
       GetInflationForBlockDirAlignment(spanFrame, mInflationMinFontSize);
     nscoord logicalBSize = nsHTMLReflowState::
       CalcLineHeight(spanFrame->GetContent(), spanFrame->StyleContext(),
                      mBlockReflowState->ComputedHeight(),
                      inflation);
     nscoord contentBSize = spanFramePFD->mBounds.BSize(lineWM) -
       spanFramePFD->mBorderPadding.BStart(frameWM) -
       spanFramePFD->mBorderPadding.BEnd(frameWM);
     // Special-case for a ::first-letter frame, set the line height to
     // the frame block size if the user has left line-height == normal
     if (spanFramePFD->GetFlag(PFD_ISLETTERFRAME) &&
         !spanFrame->GetPrevInFlow() &&
         spanFrame->StyleText()->mLineHeight.GetUnit() == eStyleUnit_Normal) {
       logicalBSize = spanFramePFD->mBounds.BSize(lineWM);
     }
     nscoord leading = logicalBSize - contentBSize;
     psd->mBStartLeading = leading / 2;
     psd->mBEndLeading = leading - psd->mBStartLeading;
     psd->mLogicalBSize = logicalBSize;
     if (zeroEffectiveSpanBox) {
       // When the span-box is to be ignored, zero out the initial
       // values so that the span doesn't impact the final line
       // height. The contents of the span can impact the final line
       // height.
       // Note that things are readjusted for this span after its children
       // are reflowed
       minBCoord = BLOCKDIR_ALIGN_FRAMES_NO_MINIMUM;
       maxBCoord = BLOCKDIR_ALIGN_FRAMES_NO_MAXIMUM;
     }
     else {
       // The initial values for the min and max block coord values are in the
       // span's coordinate space, and cover the logical block size of the span.
       // If there are child frames in this span that stick out of this area
       // then the minBCoord and maxBCoord are updated by the amount of logical
       // blockSize that is outside this range.
       minBCoord = spanFramePFD->mBorderPadding.BStart(frameWM) -
                   psd->mBStartLeading;
       maxBCoord = minBCoord + psd->mLogicalBSize;
     }
     // This is the distance from the top edge of the parents visual
     // box to the baseline. The span already computed this for us,
     // so just use it.
     *psd->mBaseline = baselineBCoord = spanFramePFD->mAscent;
 #ifdef NOISY_BLOCKDIR_ALIGN
     printf("[%sSpan]", (psd == mRootSpan)?"Root":"");
     nsFrame::ListTag(stdout, spanFrame);
     printf(": baseLine=%d logicalBSize=%d topLeading=%d h=%d bp=%d,%d zeroEffectiveSpanBox=%s\n",
            baselineBCoord, psd->mLogicalBSize, psd->mBStartLeading,
            spanFramePFD->mBounds.BSize(lineWM),
            spanFramePFD->mBorderPadding.Top(frameWM),
            spanFramePFD->mBorderPadding.Bottom(frameWM),
            zeroEffectiveSpanBox ? "yes" : "no");
 #endif
   }
   nscoord maxStartBoxBSize = 0;
   nscoord maxEndBoxBSize = 0;
   PerFrameData* pfd = psd->mFirstFrame;
   while (nullptr != pfd) {
     nsIFrame* frame = pfd->mFrame;
     WritingMode frameWM = frame->GetWritingMode();
     // sanity check (see bug 105168, non-reproducible crashes from null frame)
     NS_ASSERTION(frame, "null frame in PerFrameData - something is very very bad");
     if (!frame) {
       return;
     }
     // Compute the logical block size of the frame
     nscoord logicalBSize;
     PerSpanData* frameSpan = pfd->mSpan;
     if (frameSpan) {
       // For span frames the logical-block-size and start-leading were
       // pre-computed when the span was reflowed.
       logicalBSize = frameSpan->mLogicalBSize;
     }
     else {
       // For other elements the logical block size is the same as the
       // frame's block size plus its margins.
       logicalBSize = pfd->mBounds.BSize(lineWM) +
                      pfd->mMargin.BStartEnd(frameWM);
       if (logicalBSize < 0 &&
           mPresContext->CompatibilityMode() == eCompatibility_NavQuirks) {
         pfd->mAscent -= logicalBSize;
         logicalBSize = 0;
       }
     }
     // Get vertical-align property ("vertical-align" is the CSS name for
     // block-direction align)
     const nsStyleCoord& verticalAlign =
       frame->StyleTextReset()->mVerticalAlign;
     uint8_t verticalAlignEnum = frame->VerticalAlignEnum();
 #ifdef NOISY_BLOCKDIR_ALIGN
     printf("  [frame]");
     nsFrame::ListTag(stdout, frame);
     printf(": verticalAlignUnit=%d (enum == %d",
            verticalAlign.GetUnit(),
            ((eStyleUnit_Enumerated == verticalAlign.GetUnit())
             ? verticalAlign.GetIntValue()
             : -1));
     if (verticalAlignEnum != nsIFrame::eInvalidVerticalAlign) {
       printf(", after SVG dominant-baseline conversion == %d",
              verticalAlignEnum);
     }
     printf(")\n");
 #endif
     if (verticalAlignEnum != nsIFrame::eInvalidVerticalAlign) {
       switch (verticalAlignEnum) {
         default:
         case NS_STYLE_VERTICAL_ALIGN_BASELINE:
         {
           // The element's baseline is aligned with the baseline of
           // the parent.
           pfd->mBounds.BStart(lineWM) = baselineBCoord - pfd->mAscent;
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_SUB:
         {
           // Lower the baseline of the box to the subscript offset
           // of the parent's box. This is identical to the baseline
           // alignment except for the addition of the subscript
           // offset to the baseline BCoord.
           nscoord parentSubscript = fm->SubscriptOffset();
           nscoord revisedBaselineBCoord = baselineBCoord + parentSubscript;
           pfd->mBounds.BStart(lineWM) = revisedBaselineBCoord - pfd->mAscent;
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_SUPER:
         {
           // Raise the baseline of the box to the superscript offset
           // of the parent's box. This is identical to the baseline
           // alignment except for the subtraction of the superscript
           // offset to the baseline BCoord.
           nscoord parentSuperscript = fm->SuperscriptOffset();
           nscoord revisedBaselineBCoord = baselineBCoord - parentSuperscript;
           pfd->mBounds.BStart(lineWM) = revisedBaselineBCoord - pfd->mAscent;
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_TOP:
         {
           pfd->mBlockDirAlign = VALIGN_TOP;
           nscoord subtreeBSize = logicalBSize;
           if (frameSpan) {
             subtreeBSize = frameSpan->mMaxBCoord - frameSpan->mMinBCoord;
             NS_ASSERTION(subtreeBSize >= logicalBSize,
                          "unexpected subtree block size");
           }
           if (subtreeBSize > maxStartBoxBSize) {
             maxStartBoxBSize = subtreeBSize;
           }
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_BOTTOM:
         {
           pfd->mBlockDirAlign = VALIGN_BOTTOM;
           nscoord subtreeBSize = logicalBSize;
           if (frameSpan) {
             subtreeBSize = frameSpan->mMaxBCoord - frameSpan->mMinBCoord;
             NS_ASSERTION(subtreeBSize >= logicalBSize,
                          "unexpected subtree block size");
           }
           if (subtreeBSize > maxEndBoxBSize) {
             maxEndBoxBSize = subtreeBSize;
           }
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_MIDDLE:
         {
           // Align the midpoint of the frame with 1/2 the parents
           // x-height above the baseline.
           nscoord parentXHeight = fm->XHeight();
           if (frameSpan) {
             pfd->mBounds.BStart(lineWM) = baselineBCoord -
               (parentXHeight + pfd->mBounds.BSize(lineWM))/2;
           }
           else {
             pfd->mBounds.BStart(lineWM) = baselineBCoord -
               (parentXHeight + logicalBSize)/2 +
               pfd->mMargin.BStart(frameWM);
           }
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_TEXT_TOP:
         {
           // The top of the logical box is aligned with the top of
           // the parent element's text.
           nscoord parentAscent = fm->MaxAscent();
           if (frameSpan) {
             pfd->mBounds.BStart(lineWM) = baselineBCoord - parentAscent -
               pfd->mBorderPadding.BStart(frameWM) + frameSpan->mBStartLeading;
           }
           else {
             pfd->mBounds.BStart(lineWM) = baselineBCoord - parentAscent +
                                           pfd->mMargin.BStart(frameWM);
           }
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM:
         {
           // The bottom of the logical box is aligned with the
           // bottom of the parent elements text.
           nscoord parentDescent = fm->MaxDescent();
           if (frameSpan) {
             pfd->mBounds.BStart(lineWM) = baselineBCoord + parentDescent -
                                           pfd->mBounds.BSize(lineWM) +
                                           pfd->mBorderPadding.BEnd(frameWM) -
                                           frameSpan->mBEndLeading;
           }
           else {
             pfd->mBounds.BStart(lineWM) = baselineBCoord + parentDescent -
                                           pfd->mBounds.BSize(lineWM) -
                                           pfd->mMargin.BEnd(frameWM);
           }
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
         case NS_STYLE_VERTICAL_ALIGN_MIDDLE_WITH_BASELINE:
         {
           // Align the midpoint of the frame with the baseline of the parent.
           if (frameSpan) {
             pfd->mBounds.BStart(lineWM) = baselineBCoord -
                                           pfd->mBounds.BSize(lineWM)/2;
           }
           else {
             pfd->mBounds.BStart(lineWM) = baselineBCoord - logicalBSize/2 +
                                           pfd->mMargin.BStart(frameWM);
           }
           pfd->mBlockDirAlign = VALIGN_OTHER;
           break;
         }
       }
     } else {
       // We have either a coord, a percent, or a calc().
       nscoord pctBasis = 0;
       if (verticalAlign.HasPercent()) {
         // Percentages are like lengths, except treated as a percentage
         // of the elements line block size value.
         float inflation =
           GetInflationForBlockDirAlignment(frame, mInflationMinFontSize);
         pctBasis = nsHTMLReflowState::CalcLineHeight(frame->GetContent(),
           frame->StyleContext(), mBlockReflowState->ComputedBSize(),
           inflation);
       }
       nscoord offset =
         nsRuleNode::ComputeCoordPercentCalc(verticalAlign, pctBasis);
       // According to the CSS2 spec (10.8.1), a positive value
       // "raises" the box by the given distance while a negative value
       // "lowers" the box by the given distance (with zero being the
       // baseline). Since Y coordinates increase towards the bottom of
       // the screen we reverse the sign.
       nscoord revisedBaselineBCoord = baselineBCoord - offset;
       pfd->mBounds.BStart(lineWM) = revisedBaselineBCoord - pfd->mAscent;
       pfd->mBlockDirAlign = VALIGN_OTHER;
     }
     // Update minBCoord/maxBCoord for frames that we just placed. Do not factor
     // text into the equation.
     if (pfd->mBlockDirAlign == VALIGN_OTHER) {
       // Text frames do not contribute to the min/max Y values for the
       // line (instead their parent frame's font-size contributes).
       // XXXrbs -- relax this restriction because it causes text frames
       //           to jam together when 'font-size-adjust' is enabled
       //           and layout is using dynamic font heights (bug 20394)
       //        -- Note #1: With this code enabled and with the fact that we are not
       //           using Em[Ascent|Descent] as nsDimensions for text metrics in
       //           GFX mean that the discussion in bug 13072 cannot hold.
       //        -- Note #2: We still don't want empty-text frames to interfere.
       //           For example in quirks mode, avoiding empty text frames prevents
       //           "tall" lines around elements like <hr> since the rules of <hr>
       //           in quirks.css have pseudo text contents with LF in them.
 #if 0
       if (!pfd->GetFlag(PFD_ISTEXTFRAME)) {
 #else
       // Only consider non empty text frames when line-height=normal
       bool canUpdate = !pfd->GetFlag(PFD_ISTEXTFRAME);
       if (!canUpdate && pfd->GetFlag(PFD_ISNONWHITESPACETEXTFRAME)) {
         canUpdate =
           frame->StyleText()->mLineHeight.GetUnit() == eStyleUnit_Normal;
       }
       if (canUpdate) {
 #endif
         nscoord blockStart, blockEnd;
         if (frameSpan) {
           // For spans that were are now placing, use their position
           // plus their already computed min-Y and max-Y values for
           // computing blockStart and blockEnd.
           blockStart = pfd->mBounds.BStart(lineWM) + frameSpan->mMinBCoord;
           blockEnd = pfd->mBounds.BStart(lineWM) + frameSpan->mMaxBCoord;
         }
         else {
           blockStart = pfd->mBounds.BStart(lineWM) -
                        pfd->mMargin.BStart(frameWM);
           blockEnd = blockStart + logicalBSize;
         }
         if (!preMode &&
             mPresContext->CompatibilityMode() != eCompatibility_FullStandards &&
             !logicalBSize) {
           // Check if it's a BR frame that is not alone on its line (it
           // is given a block size of zero to indicate this), and if so reset
           // blockStart and blockEnd so that BR frames don't influence the line.
           if (nsGkAtoms::brFrame == frame->GetType()) {
             blockStart = BLOCKDIR_ALIGN_FRAMES_NO_MINIMUM;
             blockEnd = BLOCKDIR_ALIGN_FRAMES_NO_MAXIMUM;
           }
         }
         if (blockStart < minBCoord) minBCoord = blockStart;
         if (blockEnd > maxBCoord) maxBCoord = blockEnd;
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("     [frame]raw: a=%d h=%d bp=%d,%d logical: h=%d leading=%d y=%d minBCoord=%d maxBCoord=%d\n",
                pfd->mAscent, pfd->mBounds.BSize(lineWM),
                pfd->mBorderPadding.Top(frameWM),
                pfd->mBorderPadding.Bottom(frameWM),
                logicalBSize,
                frameSpan ? frameSpan->mBStartLeading : 0,
                pfd->mBounds.BStart(lineWM), minBCoord, maxBCoord);
 #endif
       }
       if (psd != mRootSpan) {
         frame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
       }
     }
     pfd = pfd->mNext;
   }
   // Factor in the minimum line block-size when handling the root-span for
   // the block.
   if (psd == mRootSpan) {
     // We should factor in the block element's minimum line-height (as
     // defined in section 10.8.1 of the css2 spec) assuming that
     // mZeroEffectiveSpanBox is not set on the root span.  This only happens
     // in some cases in quirks mode:
     //  (1) if the root span contains non-whitespace text directly (this
     //      is handled by mZeroEffectiveSpanBox
     //  (2) if this line has a bullet
     //  (3) if this is the last line of an LI, DT, or DD element
     //      (The last line before a block also counts, but not before a
     //      BR) (NN4/IE5 quirk)
     // (1) and (2) above
     bool applyMinLH = !psd->mZeroEffectiveSpanBox || mHasBullet;
     bool isLastLine = (!mLineBox->IsLineWrapped() && !mLineEndsInBR);
     if (!applyMinLH && isLastLine) {
       nsIContent* blockContent = mRootSpan->mFrame->mFrame->GetContent();
       if (blockContent) {
         nsIAtom *blockTagAtom = blockContent->Tag();
         // (3) above, if the last line of LI, DT, or DD
         if (blockTagAtom == nsGkAtoms::li ||
             blockTagAtom == nsGkAtoms::dt ||
             blockTagAtom == nsGkAtoms::dd) {
           applyMinLH = true;
         }
       }
     }
     if (applyMinLH) {
       if (psd->mHasNonemptyContent || preMode || mHasBullet) {
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("  [span]==> adjusting min/maxBCoord: currentValues: %d,%d", minBCoord, maxBCoord);
 #endif
         nscoord minimumLineBSize = mMinLineBSize;
         nscoord blockStart =
           -nsLayoutUtils::GetCenteredFontBaseline(fm, minimumLineBSize);
         nscoord blockEnd = blockStart + minimumLineBSize;
         if (blockStart < minBCoord) minBCoord = blockStart;
         if (blockEnd > maxBCoord) maxBCoord = blockEnd;
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf(" new values: %d,%d\n", minBCoord, maxBCoord);
 #endif
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("            Used mMinLineBSize: %d, blockStart: %d, blockEnd: %d\n", mMinLineBSize, blockStart, blockEnd);
 #endif
       }
       else {
         // XXX issues:
         // [1] BR's on empty lines stop working
         // [2] May not honor css2's notion of handling empty elements
         // [3] blank lines in a pre-section ("\n") (handled with preMode)
         // XXX Are there other problems with this?
 #ifdef NOISY_BLOCKDIR_ALIGN
         printf("  [span]==> zapping min/maxBCoord: currentValues: %d,%d newValues: 0,0\n",
                minBCoord, maxBCoord);
 #endif
         minBCoord = maxBCoord = 0;
       }
     }
   }
   if ((minBCoord == BLOCKDIR_ALIGN_FRAMES_NO_MINIMUM) ||
       (maxBCoord == BLOCKDIR_ALIGN_FRAMES_NO_MAXIMUM)) {
     minBCoord = maxBCoord = baselineBCoord;
   }
   if ((psd != mRootSpan) && (psd->mZeroEffectiveSpanBox)) {
 #ifdef NOISY_BLOCKDIR_ALIGN
     printf("   [span]adjusting for zeroEffectiveSpanBox\n");
     printf("     Original: minBCoord=%d, maxBCoord=%d, bSize=%d, ascent=%d, logicalBSize=%d, topLeading=%d, bottomLeading=%d\n",
            minBCoord, maxBCoord, spanFramePFD->mBounds.BSize(frameWM),
            spanFramePFD->mAscent,
            psd->mLogicalBSize, psd->mBStartLeading, psd->mBEndLeading);
 #endif
     nscoord goodMinBCoord = spanFramePFD->mBorderPadding.BStart(frameWM) -
                             psd->mBStartLeading;
     nscoord goodMaxBCoord = goodMinBCoord + psd->mLogicalBSize;
     // For cases like the one in bug 714519 (text-decoration placement
     // or making nsLineLayout::IsZeroBSize() handle
     // vertical-align:top/bottom on a descendant of the line that's not
     // a child of it), we want to treat elements that are
     // vertical-align: top or bottom somewhat like children for the
     // purposes of this quirk.  To some extent, this is guessing, since
     // they might end up being aligned anywhere.  However, we'll guess
     // that they'll be placed aligned with the top or bottom of this
     // frame (as though this frame is the only thing in the line).
     // (Guessing isn't crazy, since all we're doing is reducing the
     // scope of a quirk and making the behavior more standards-like.)
     if (maxStartBoxBSize > maxBCoord - minBCoord) {
       // Distribute maxStartBoxBSize to ascent (baselineBCoord - minBCoord), and
       // then to descent (maxBCoord - baselineBCoord) by adjusting minBCoord or
       // maxBCoord, but not to exceed goodMinBCoord and goodMaxBCoord.
       nscoord distribute = maxStartBoxBSize - (maxBCoord - minBCoord);
       nscoord ascentSpace = std::max(minBCoord - goodMinBCoord, 0);
       if (distribute > ascentSpace) {
         distribute -= ascentSpace;
         minBCoord -= ascentSpace;
         nscoord descentSpace = std::max(goodMaxBCoord - maxBCoord, 0);
         if (distribute > descentSpace) {
           maxBCoord += descentSpace;
         } else {
           maxBCoord += distribute;
         }
       } else {
         minBCoord -= distribute;
       }
     }
     if (maxEndBoxBSize > maxBCoord - minBCoord) {
       // Likewise, but preferring descent to ascent.
       nscoord distribute = maxEndBoxBSize - (maxBCoord - minBCoord);
       nscoord descentSpace = std::max(goodMaxBCoord - maxBCoord, 0);
       if (distribute > descentSpace) {
         distribute -= descentSpace;
         maxBCoord += descentSpace;
         nscoord ascentSpace = std::max(minBCoord - goodMinBCoord, 0);
         if (distribute > ascentSpace) {
           minBCoord -= ascentSpace;
         } else {
           minBCoord -= distribute;
         }
       } else {
         maxBCoord += distribute;
       }
     }
     if (minBCoord > goodMinBCoord) {
       nscoord adjust = minBCoord - goodMinBCoord; // positive
       // shrink the logical extents
       psd->mLogicalBSize -= adjust;
       psd->mBStartLeading -= adjust;
     }
     if (maxBCoord < goodMaxBCoord) {
       nscoord adjust = goodMaxBCoord - maxBCoord;
       psd->mLogicalBSize -= adjust;
       psd->mBEndLeading -= adjust;
     }
     if (minBCoord > 0) {
       // shrink the content by moving its block start down.  This is tricky,
       // since the block start is the 0 for many coordinates, so what we do is
       // move everything else up.
       spanFramePFD->mAscent -= minBCoord; // move the baseline up
       spanFramePFD->mBounds.BSize(lineWM) -= minBCoord; // move the block end up
       psd->mBStartLeading += minBCoord;
       *psd->mBaseline -= minBCoord;
       pfd = psd->mFirstFrame;
       while (nullptr != pfd) {
         pfd->mBounds.BStart(lineWM) -= minBCoord; // move all the children
                                                   // back up
         pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
         pfd = pfd->mNext;
       }
       maxBCoord -= minBCoord; // since minBCoord is in the frame's own
                               // coordinate system
       minBCoord = 0;
     }
     if (maxBCoord < spanFramePFD->mBounds.BSize(lineWM)) {
       nscoord adjust = spanFramePFD->mBounds.BSize(lineWM) - maxBCoord;
       spanFramePFD->mBounds.BSize(lineWM) -= adjust; // move the bottom up
       psd->mBEndLeading += adjust;
     }
 #ifdef NOISY_BLOCKDIR_ALIGN
     printf("     New: minBCoord=%d, maxBCoord=%d, bSize=%d, ascent=%d, logicalBSize=%d, topLeading=%d, bottomLeading=%d\n",
            minBCoord, maxBCoord, spanFramePFD->mBounds.BSize(lineWM),
            spanFramePFD->mAscent,
            psd->mLogicalBSize, psd->mBStartLeading, psd->mBEndLeading);
 #endif
   }
   psd->mMinBCoord = minBCoord;
   psd->mMaxBCoord = maxBCoord;
 #ifdef NOISY_BLOCKDIR_ALIGN
   printf("  [span]==> minBCoord=%d maxBCoord=%d delta=%d maxStartBoxBSize=%d maxEndBoxBSize=%d\n",
          minBCoord, maxBCoord, maxBCoord - minBCoord, maxStartBoxBSize, maxEndBoxBSize);
 #endif
   if (maxStartBoxBSize > mMaxStartBoxBSize) {
     mMaxStartBoxBSize = maxStartBoxBSize;
   }
   if (maxEndBoxBSize > mMaxEndBoxBSize) {
     mMaxEndBoxBSize = maxEndBoxBSize;
   }
 }
 static void SlideSpanFrameRect(nsIFrame* aFrame, nscoord aDeltaWidth)
 {
   // This should not use nsIFrame::MovePositionBy because it happens
   // prior to relative positioning.  In particular, because
   // nsBlockFrame::PlaceLine calls aLineLayout.TrimTrailingWhiteSpace()
   // prior to calling aLineLayout.RelativePositionFrames().
   nsPoint p = aFrame->GetPosition();
   p.x -= aDeltaWidth;
   aFrame->SetPosition(p);
 }
 bool
 nsLineLayout::TrimTrailingWhiteSpaceIn(PerSpanData* psd,
                                        nscoord* aDeltaISize)
 {
   PerFrameData* pfd = psd->mFirstFrame;
   if (!pfd) {
     *aDeltaISize = 0;
     return false;
   }
   pfd = pfd->Last();
   while (nullptr != pfd) {
 #ifdef REALLY_NOISY_TRIM
     nsFrame::ListTag(stdout, (psd == mRootSpan
                               ? mBlockReflowState->frame
                               : psd->mFrame->mFrame));
     printf(": attempting trim of ");
     nsFrame::ListTag(stdout, pfd->mFrame);
     printf("\n");
 #endif
     PerSpanData* childSpan = pfd->mSpan;
     WritingMode lineWM = mRootSpan->mWritingMode;
     if (childSpan) {
       // Maybe the child span has the trailing white-space in it?
       if (TrimTrailingWhiteSpaceIn(childSpan, aDeltaISize)) {
         nscoord deltaISize = *aDeltaISize;
         if (deltaISize) {
           // Adjust the child spans frame size
           pfd->mBounds.ISize(lineWM) -= deltaISize;
           if (psd != mRootSpan) {
             // When the child span is not a direct child of the block
             // we need to update the child spans frame rectangle
             // because it most likely will not be done again. Spans
             // that are direct children of the block will be updated
             // later, however, because the BlockDirAlignFrames method
             // will be run after this method.
             nsIFrame* f = pfd->mFrame;
             LogicalRect r(lineWM, f->GetRect(), mContainerWidth);
             r.ISize(lineWM) -= deltaISize;
             f->SetRect(lineWM, r, mContainerWidth);
           }
           // Adjust the inline end edge of the span that contains the child span
           psd->mICoord -= deltaISize;
           // Slide any frames that follow the child span over by the
           // correct amount. The only thing that can follow the child
           // span is empty stuff, so we are just making things
           // sensible (keeping the combined area honest).
           while (pfd->mNext) {
             pfd = pfd->mNext;
             pfd->mBounds.IStart(lineWM) -= deltaISize;
             if (psd != mRootSpan) {
               // When the child span is not a direct child of the block
               // we need to update the child span's frame rectangle
               // because it most likely will not be done again. Spans
               // that are direct children of the block will be updated
               // later, however, because the BlockDirAlignFrames method
               // will be run after this method.
               SlideSpanFrameRect(pfd->mFrame, deltaISize);
             }
           }
         }
         return true;
       }
     }
     else if (!pfd->GetFlag(PFD_ISTEXTFRAME) &&
              !pfd->GetFlag(PFD_SKIPWHENTRIMMINGWHITESPACE)) {
       // If we hit a frame on the end that's not text and not a placeholder,
       // then there is no trailing whitespace to trim. Stop the search.
       *aDeltaISize = 0;
       return true;
     }
     else if (pfd->GetFlag(PFD_ISTEXTFRAME)) {
       // Call TrimTrailingWhiteSpace even on empty textframes because they
       // might have a soft hyphen which should now appear, changing the frame's
       // width
       nsTextFrame::TrimOutput trimOutput = static_cast<nsTextFrame*>(pfd->mFrame)->
           TrimTrailingWhiteSpace(mBlockReflowState->rendContext);
 #ifdef NOISY_TRIM
       nsFrame::ListTag(stdout, (psd == mRootSpan
                                 ? mBlockReflowState->frame
                                 : psd->mFrame->mFrame));
       printf(": trim of ");
       nsFrame::ListTag(stdout, pfd->mFrame);
       printf(" returned %d\n", trimOutput.mDeltaWidth);
 #endif
       if (trimOutput.mLastCharIsJustifiable && pfd->mJustificationNumSpaces > 0) {
         pfd->mJustificationNumSpaces--;
       }
       if (trimOutput.mChanged) {
         pfd->SetFlag(PFD_RECOMPUTEOVERFLOW, true);
       }
       if (trimOutput.mDeltaWidth) {
         pfd->mBounds.ISize(lineWM) -= trimOutput.mDeltaWidth;
         // See if the text frame has already been placed in its parent
         if (psd != mRootSpan) {
           // The frame was already placed during psd's
           // reflow. Update the frames rectangle now.
           pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
         }
         // Adjust containing span's right edge
         psd->mICoord -= trimOutput.mDeltaWidth;
         // Slide any frames that follow the text frame over by the
         // right amount. The only thing that can follow the text
         // frame is empty stuff, so we are just making things
         // sensible (keeping the combined area honest).
         while (pfd->mNext) {
           pfd = pfd->mNext;
           pfd->mBounds.IStart(lineWM) -= trimOutput.mDeltaWidth;
           if (psd != mRootSpan) {
             // When the child span is not a direct child of the block
             // we need to update the child spans frame rectangle
             // because it most likely will not be done again. Spans
             // that are direct children of the block will be updated
             // later, however, because the BlockDirAlignFrames method
             // will be run after this method.
             SlideSpanFrameRect(pfd->mFrame, trimOutput.mDeltaWidth);
           }
         }
       }
       if (pfd->GetFlag(PFD_ISNONEMPTYTEXTFRAME) || trimOutput.mChanged) {
         // Pass up to caller so they can shrink their span
         *aDeltaISize = trimOutput.mDeltaWidth;
         return true;
       }
     }
     pfd = pfd->mPrev;
   }
   *aDeltaISize = 0;
   return false;
 }
 bool
 nsLineLayout::TrimTrailingWhiteSpace()
 {
   PerSpanData* psd = mRootSpan;
   nscoord deltaISize;
   TrimTrailingWhiteSpaceIn(psd, &deltaISize);
   return 0 != deltaISize;
 }
 void
 nsLineLayout::ComputeJustificationWeights(PerSpanData* aPSD,
                                           int32_t* aNumSpaces,
                                           int32_t* aNumLetters)
 {
   NS_ASSERTION(aPSD, "null arg");
   NS_ASSERTION(aNumSpaces, "null arg");
   NS_ASSERTION(aNumLetters, "null arg");
   int32_t numSpaces = 0;
   int32_t numLetters = 0;
   for (PerFrameData* pfd = aPSD->mFirstFrame; pfd != nullptr; pfd = pfd->mNext) {
     if (true == pfd->GetFlag(PFD_ISTEXTFRAME)) {
       numSpaces += pfd->mJustificationNumSpaces;
       numLetters += pfd->mJustificationNumLetters;
     }
     else if (pfd->mSpan != nullptr) {
       int32_t spanSpaces;
       int32_t spanLetters;
       ComputeJustificationWeights(pfd->mSpan, &spanSpaces, &spanLetters);
       numSpaces += spanSpaces;
       numLetters += spanLetters;
     }
   }
   *aNumSpaces = numSpaces;
   *aNumLetters = numLetters;
 }
 nscoord
 nsLineLayout::ApplyFrameJustification(PerSpanData* aPSD, FrameJustificationState* aState)
 {
   NS_ASSERTION(aPSD, "null arg");
   NS_ASSERTION(aState, "null arg");
   nscoord deltaICoord = 0;
   for (PerFrameData* pfd = aPSD->mFirstFrame; pfd != nullptr; pfd = pfd->mNext) {
     // Don't reposition bullets (and other frames that occur out of X-order?)
     if (!pfd->GetFlag(PFD_ISBULLET)) {
       nscoord dw = 0;
       WritingMode lineWM = mRootSpan->mWritingMode;
       pfd->mBounds.IStart(lineWM) += deltaICoord;
       if (true == pfd->GetFlag(PFD_ISTEXTFRAME)) {
         if (aState->mTotalWidthForSpaces > 0 &&
             aState->mTotalNumSpaces > 0) {
           aState->mNumSpacesProcessed += pfd->mJustificationNumSpaces;
           nscoord newAllocatedWidthForSpaces =
             (aState->mTotalWidthForSpaces*aState->mNumSpacesProcessed)
               /aState->mTotalNumSpaces;
           dw += newAllocatedWidthForSpaces - aState->mWidthForSpacesProcessed;
           aState->mWidthForSpacesProcessed = newAllocatedWidthForSpaces;
         }
         if (aState->mTotalWidthForLetters > 0 &&
             aState->mTotalNumLetters > 0) {
           aState->mNumLettersProcessed += pfd->mJustificationNumLetters;
           nscoord newAllocatedWidthForLetters =
             (aState->mTotalWidthForLetters*aState->mNumLettersProcessed)
               /aState->mTotalNumLetters;
           dw += newAllocatedWidthForLetters - aState->mWidthForLettersProcessed;
           aState->mWidthForLettersProcessed = newAllocatedWidthForLetters;
         }
         if (dw) {
           pfd->SetFlag(PFD_RECOMPUTEOVERFLOW, true);
         }
       }
       else {
         if (nullptr != pfd->mSpan) {
           dw += ApplyFrameJustification(pfd->mSpan, aState);
         }
       }
       pfd->mBounds.ISize(lineWM) += dw;
       deltaICoord += dw;
       pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
     }
   }
   return deltaICoord;
 }
 void
 nsLineLayout::InlineDirAlignFrames(nsLineBox* aLine,
                                    bool aIsLastLine)
 {
   /**
    * NOTE: aIsLastLine ain't necessarily so: it is correctly set by caller
    * only in cases where the last line needs special handling.
    */
   PerSpanData* psd = mRootSpan;
   WritingMode lineWM = psd->mWritingMode;
   NS_WARN_IF_FALSE(psd->mIEnd != NS_UNCONSTRAINEDSIZE,
                    "have unconstrained width; this should only result from "
                    "very large sizes, not attempts at intrinsic width "
                    "calculation");
   nscoord availISize = psd->mIEnd - psd->mIStart;
   nscoord remainingISize = availISize - aLine->ISize();
 #ifdef NOISY_INLINEDIR_ALIGN
   nsFrame::ListTag(stdout, mBlockReflowState->frame);
   printf(": availISize=%d lineBounds.IStart=%d lineISize=%d delta=%d\n",
          availISize, aLine->IStart(), aLine->ISize(), remainingISize);
 #endif
   // 'text-align-last: auto' is equivalent to the value of the 'text-align'
   // property except when 'text-align' is set to 'justify', in which case it
   // is 'justify' when 'text-justify' is 'distribute' and 'start' otherwise.
   //
   // XXX: the code below will have to change when we implement text-justify
   //
   nscoord dx = 0;
   uint8_t textAlign = mStyleText->mTextAlign;
   bool textAlignTrue = mStyleText->mTextAlignTrue;
   if (aIsLastLine) {
     textAlignTrue = mStyleText->mTextAlignLastTrue;
     if (mStyleText->mTextAlignLast == NS_STYLE_TEXT_ALIGN_AUTO) {
       if (textAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY) {
         textAlign = NS_STYLE_TEXT_ALIGN_DEFAULT;
       }
     } else {
       textAlign = mStyleText->mTextAlignLast;
     }
   }
   if ((remainingISize > 0 || textAlignTrue) &&
       !(mBlockReflowState->frame->IsSVGText())) {
     switch (textAlign) {
       case NS_STYLE_TEXT_ALIGN_JUSTIFY:
         int32_t numSpaces;
         int32_t numLetters;
         ComputeJustificationWeights(psd, &numSpaces, &numLetters);
         if (numSpaces > 0) {
           FrameJustificationState state =
             { numSpaces, numLetters, remainingISize, 0, 0, 0, 0, 0 };
           // Apply the justification, and make sure to update our linebox
           // width to account for it.
           aLine->ExpandBy(ApplyFrameJustification(psd, &state),
                           mContainerWidth);
           remainingISize = availISize - aLine->ISize();
           break;
         }
         // Fall through to the default case if we could not justify to fill
         // the space.
       case NS_STYLE_TEXT_ALIGN_DEFAULT:
         // default alignment is to start edge so do nothing
         break;
       case NS_STYLE_TEXT_ALIGN_LEFT:
       case NS_STYLE_TEXT_ALIGN_MOZ_LEFT:
         if (!lineWM.IsBidiLTR()) {
           dx = remainingISize;
         }
         break;
       case NS_STYLE_TEXT_ALIGN_RIGHT:
       case NS_STYLE_TEXT_ALIGN_MOZ_RIGHT:
         if (lineWM.IsBidiLTR()) {
           dx = remainingISize;
         }
         break;
       case NS_STYLE_TEXT_ALIGN_END:
         dx = remainingISize;
         break;
       case NS_STYLE_TEXT_ALIGN_CENTER:
       case NS_STYLE_TEXT_ALIGN_MOZ_CENTER:
         dx = remainingISize / 2;
         break;
     }
   }
   if (dx) {
     for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
       pfd->mBounds.IStart(lineWM) += dx;
       pfd->mFrame->SetRect(lineWM, pfd->mBounds, mContainerWidth);
     }
     aLine->IndentBy(dx, mContainerWidth);
   }
   if (mPresContext->BidiEnabled() &&
       (!mPresContext->IsVisualMode() || !lineWM.IsBidiLTR())) {
     nsBidiPresUtils::ReorderFrames(psd->mFirstFrame->mFrame,
                                    aLine->GetChildCount(),
                                    lineWM, mContainerWidth);
   }
 }
 void
 nsLineLayout::RelativePositionFrames(nsOverflowAreas& aOverflowAreas)
 {
   RelativePositionFrames(mRootSpan, aOverflowAreas);
 }
 void
 nsLineLayout::RelativePositionFrames(PerSpanData* psd, nsOverflowAreas& aOverflowAreas)
 {
   nsOverflowAreas overflowAreas;
   WritingMode wm = psd->mWritingMode;
   if (nullptr != psd->mFrame) {
     // The span's overflow areas come in three parts:
     // -- this frame's width and height
     // -- pfd->mOverflowAreas, which is the area of a bullet or the union
     // of a relatively positioned frame's absolute children
     // -- the bounds of all inline descendants
     // The former two parts are computed right here, we gather the descendants
     // below.
     // At this point psd->mFrame->mBounds might be out of date since
     // bidi reordering can move and resize the frames. So use the frame's
     // rect instead of mBounds.
     nsRect adjustedBounds(nsPoint(0, 0), psd->mFrame->mFrame->GetSize());
     overflowAreas.ScrollableOverflow().UnionRect(
       psd->mFrame->mOverflowAreas.ScrollableOverflow(), adjustedBounds);
     overflowAreas.VisualOverflow().UnionRect(
       psd->mFrame->mOverflowAreas.VisualOverflow(), adjustedBounds);
   }
   else {
     LogicalRect rect(wm, psd->mIStart, mBStartEdge,
                      psd->mICoord - psd->mIStart, mFinalLineBSize);
     // The minimum combined area for the frames that are direct
     // children of the block starts at the upper left corner of the
     // line and is sized to match the size of the line's bounding box
     // (the same size as the values returned from BlockDirAlignFrames)
     overflowAreas.VisualOverflow() = rect.GetPhysicalRect(wm, mContainerWidth);
     overflowAreas.ScrollableOverflow() = overflowAreas.VisualOverflow();
   }
   for (PerFrameData* pfd = psd->mFirstFrame; pfd; pfd = pfd->mNext) {
     nsIFrame* frame = pfd->mFrame;
     nsPoint origin = frame->GetPosition();
     // Adjust the origin of the frame
     if (pfd->GetFlag(PFD_RELATIVEPOS)) {
       //XXX temporary until ApplyRelativePositioning can handle logical offsets
       nsMargin physicalOffsets =
         pfd->mOffsets.GetPhysicalMargin(pfd->mFrame->GetWritingMode());
       // right and bottom are handled by
       // nsHTMLReflowState::ComputeRelativeOffsets
       nsHTMLReflowState::ApplyRelativePositioning(pfd->mFrame,
                                                   physicalOffsets,
                                                   &origin);
       frame->SetPosition(origin);
     }
     // We must position the view correctly before positioning its
     // descendants so that widgets are positioned properly (since only
     // some views have widgets).
     if (frame->HasView())
       nsContainerFrame::SyncFrameViewAfterReflow(mPresContext, frame,
         frame->GetView(), pfd->mOverflowAreas.VisualOverflow(),
         NS_FRAME_NO_SIZE_VIEW);
     // Note: the combined area of a child is in its coordinate
     // system. We adjust the childs combined area into our coordinate
     // system before computing the aggregated value by adding in
     // <b>x</b> and <b>y</b> which were computed above.
     nsOverflowAreas r;
     if (pfd->mSpan) {
       // Compute a new combined area for the child span before
       // aggregating it into our combined area.
       RelativePositionFrames(pfd->mSpan, r);
     } else {
       r = pfd->mOverflowAreas;
       if (pfd->GetFlag(PFD_ISTEXTFRAME)) {
         // We need to recompute overflow areas in two cases:
         // (1) When PFD_RECOMPUTEOVERFLOW is set due to trimming
         // (2) When there are text decorations, since we can't recompute the
         //     overflow area until Reflow and BlockDirAlignLine have finished
         if (pfd->GetFlag(PFD_RECOMPUTEOVERFLOW) ||
             frame->StyleContext()->HasTextDecorationLines()) {
           nsTextFrame* f = static_cast<nsTextFrame*>(frame);
           r = f->RecomputeOverflow(*mBlockReflowState);
         }
         frame->FinishAndStoreOverflow(r, frame->GetSize());
       }
       // If we have something that's not an inline but with a complex frame
       // hierarchy inside that contains views, they need to be
       // positioned.
       // All descendant views must be repositioned even if this frame
       // does have a view in case this frame's view does not have a
       // widget and some of the descendant views do have widgets --
       // otherwise the widgets won't be repositioned.
       nsContainerFrame::PositionChildViews(frame);
     }
     // Do this here (rather than along with setting the overflow rect
     // below) so we get leaf frames as well.  No need to worry
     // about the root span, since it doesn't have a frame.
     if (frame->HasView())
       nsContainerFrame::SyncFrameViewAfterReflow(mPresContext, frame,
                                                  frame->GetView(),
                                                  r.VisualOverflow(),
                                                  NS_FRAME_NO_MOVE_VIEW);
     overflowAreas.UnionWith(r + origin);
   }
   // If we just computed a spans combined area, we need to update its
   // overflow rect...
   if (psd->mFrame) {
     PerFrameData* spanPFD = psd->mFrame;
     nsIFrame* frame = spanPFD->mFrame;
     frame->FinishAndStoreOverflow(overflowAreas, frame->GetSize());
   }
   aOverflowAreas = overflowAreas;
 }

The Tor Browser / annotate

layout/generic/nsLineLayout.cpp@b8a032363ba2 (annotated)

layout/generic/nsLineLayout.cpp