Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 997 insertions, 0 deletions

diff --git a/layout/tables/BasicTableLayoutStrategy.cpp b/layout/tables/BasicTableLayoutStrategy.cpp
new file mode 100644
index 0000000000..449c2654e8
--- /dev/null
+++ b/layout/tables/BasicTableLayoutStrategy.cpp
@@ -0,0 +1,997 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+// vim:cindent:ts=2:et:sw=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/. */
+
+/*
+ * Web-compatible algorithms that determine column and table widths,
+ * used for CSS2's 'table-layout: auto'.
+ */
+
+#include "BasicTableLayoutStrategy.h"
+
+#include <algorithm>
+
+#include "nsTableFrame.h"
+#include "nsTableColFrame.h"
+#include "nsTableCellFrame.h"
+#include "nsLayoutUtils.h"
+#include "nsGkAtoms.h"
+#include "SpanningCellSorter.h"
+#include "nsIContent.h"
+
+using namespace mozilla;
+using namespace mozilla::layout;
+
+#undef DEBUG_TABLE_STRATEGY
+
+BasicTableLayoutStrategy::BasicTableLayoutStrategy(nsTableFrame* aTableFrame)
+    : nsITableLayoutStrategy(nsITableLayoutStrategy::Auto),
+      mTableFrame(aTableFrame) {
+  MarkIntrinsicISizesDirty();
+}
+
+/* virtual */
+BasicTableLayoutStrategy::~BasicTableLayoutStrategy() = default;
+
+/* virtual */
+nscoord BasicTableLayoutStrategy::GetMinISize(gfxContext* aRenderingContext) {
+  DISPLAY_MIN_INLINE_SIZE(mTableFrame, mMinISize);
+  if (mMinISize == NS_INTRINSIC_ISIZE_UNKNOWN) {
+    ComputeIntrinsicISizes(aRenderingContext);
+  }
+  return mMinISize;
+}
+
+/* virtual */
+nscoord BasicTableLayoutStrategy::GetPrefISize(gfxContext* aRenderingContext,
+                                               bool aComputingSize) {
+  DISPLAY_PREF_INLINE_SIZE(mTableFrame, mPrefISize);
+  NS_ASSERTION((mPrefISize == NS_INTRINSIC_ISIZE_UNKNOWN) ==
+                   (mPrefISizePctExpand == NS_INTRINSIC_ISIZE_UNKNOWN),
+               "dirtyness out of sync");
+  if (mPrefISize == NS_INTRINSIC_ISIZE_UNKNOWN) {
+    ComputeIntrinsicISizes(aRenderingContext);
+  }
+  return aComputingSize ? mPrefISizePctExpand : mPrefISize;
+}
+
+struct CellISizeInfo {
+  CellISizeInfo(nscoord aMinCoord, nscoord aPrefCoord, float aPrefPercent,
+                bool aHasSpecifiedISize)
+      : hasSpecifiedISize(aHasSpecifiedISize),
+        minCoord(aMinCoord),
+        prefCoord(aPrefCoord),
+        prefPercent(aPrefPercent) {}
+
+  bool hasSpecifiedISize;
+  nscoord minCoord;
+  nscoord prefCoord;
+  float prefPercent;
+};
+
+// Used for both column and cell calculations.  The parts needed only
+// for cells are skipped when aIsCell is false.
+static CellISizeInfo GetISizeInfo(gfxContext* aRenderingContext,
+                                  nsIFrame* aFrame, WritingMode aWM,
+                                  bool aIsCell) {
+  nscoord minCoord, prefCoord;
+  const nsStylePosition* stylePos = aFrame->StylePosition();
+  bool isQuirks =
+      aFrame->PresContext()->CompatibilityMode() == eCompatibility_NavQuirks;
+  nscoord boxSizingToBorderEdge = 0;
+  if (aIsCell) {
+    // If aFrame is a container for font size inflation, then shrink
+    // wrapping inside of it should not apply font size inflation.
+    AutoMaybeDisableFontInflation an(aFrame);
+
+    minCoord = aFrame->GetMinISize(aRenderingContext);
+    prefCoord = aFrame->GetPrefISize(aRenderingContext);
+    // Until almost the end of this function, minCoord and prefCoord
+    // represent the box-sizing based isize values (which mean they
+    // should include inline padding and border width when
+    // box-sizing is set to border-box).
+    // Note that this function returns border-box isize, we add the
+    // outer edges near the end of this function.
+
+    // XXX Should we ignore percentage padding?
+    nsIFrame::IntrinsicSizeOffsetData offsets = aFrame->IntrinsicISizeOffsets();
+
+    // In quirks mode, table cell isize should be content-box,
+    // but bsize should be border box.
+    // Because of this historic anomaly, we do not use quirk.css.
+    // (We can't specify one value of box-sizing for isize and another
+    // for bsize).
+    // For this reason, we also do not use box-sizing for just one of
+    // them, as this may be confusing.
+    if (isQuirks || stylePos->mBoxSizing == StyleBoxSizing::Content) {
+      boxSizingToBorderEdge = offsets.padding + offsets.border;
+    } else {
+      // StyleBoxSizing::Border and standards-mode
+      minCoord += offsets.padding + offsets.border;
+      prefCoord += offsets.padding + offsets.border;
+    }
+  } else {
+    minCoord = 0;
+    prefCoord = 0;
+  }
+  float prefPercent = 0.0f;
+  bool hasSpecifiedISize = false;
+
+  const auto& iSize = stylePos->ISize(aWM);
+  // NOTE: We're ignoring calc() units with both lengths and percentages here,
+  // for lack of a sensible idea for what to do with them.  This means calc()
+  // with percentages is basically handled like 'auto' for table cells and
+  // columns.
+  if (iSize.ConvertsToLength()) {
+    hasSpecifiedISize = true;
+    nscoord c = iSize.ToLength();
+    // Quirk: A cell with "nowrap" set and a coord value for the
+    // isize which is bigger than the intrinsic minimum isize uses
+    // that coord value as the minimum isize.
+    // This is kept up-to-date with dynamic changes to nowrap by code in
+    // nsTableCellFrame::AttributeChanged
+    if (aIsCell && c > minCoord && isQuirks &&
+        aFrame->GetContent()->AsElement()->HasAttr(kNameSpaceID_None,
+                                                   nsGkAtoms::nowrap)) {
+      minCoord = c;
+    }
+    prefCoord = std::max(c, minCoord);
+  } else if (iSize.ConvertsToPercentage()) {
+    prefPercent = iSize.ToPercentage();
+  } else if (aIsCell) {
+    switch (iSize.tag) {
+      case StyleSize::Tag::MaxContent:
+        // 'inline-size' only affects pref isize, not min
+        // isize, so don't change anything
+        break;
+      case StyleSize::Tag::MinContent:
+        prefCoord = minCoord;
+        break;
+      case StyleSize::Tag::MozAvailable:
+      case StyleSize::Tag::FitContent:
+      case StyleSize::Tag::FitContentFunction:
+        // TODO: Bug 1708310: Make sure fit-content() work properly in table.
+      case StyleSize::Tag::Auto:
+      case StyleSize::Tag::LengthPercentage:
+        break;
+    }
+  }
+
+  StyleMaxSize maxISize = stylePos->MaxISize(aWM);
+  if (nsIFrame::ToExtremumLength(maxISize)) {
+    if (!aIsCell || maxISize.IsMozAvailable()) {
+      maxISize = StyleMaxSize::None();
+    } else if (maxISize.IsFitContent() || maxISize.IsFitContentFunction()) {
+      // TODO: Bug 1708310: Make sure fit-content() work properly in table.
+      // for 'max-inline-size', '-moz-fit-content' is like 'max-content'
+      maxISize = StyleMaxSize::MaxContent();
+    }
+  }
+  // XXX To really implement 'max-inline-size' well, we'd need to store
+  // it separately on the columns.
+  const LogicalSize zeroSize(aWM);
+  if (maxISize.ConvertsToLength() || nsIFrame::ToExtremumLength(maxISize)) {
+    nscoord c = aFrame
+                    ->ComputeISizeValue(aRenderingContext, aWM, zeroSize,
+                                        zeroSize, 0, maxISize)
+                    .mISize;
+    minCoord = std::min(c, minCoord);
+    prefCoord = std::min(c, prefCoord);
+  } else if (maxISize.ConvertsToPercentage()) {
+    float p = maxISize.ToPercentage();
+    if (p < prefPercent) {
+      prefPercent = p;
+    }
+  }
+
+  StyleSize minISize = stylePos->MinISize(aWM);
+  if (nsIFrame::ToExtremumLength(maxISize)) {
+    if (!aIsCell || minISize.IsMozAvailable()) {
+      minISize = StyleSize::LengthPercentage(LengthPercentage::Zero());
+    } else if (minISize.IsFitContent() || minISize.IsFitContentFunction()) {
+      // TODO: Bug 1708310: Make sure fit-content() work properly in table.
+      // for 'min-inline-size', '-moz-fit-content' is like 'min-content'
+      minISize = StyleSize::MinContent();
+    }
+  }
+
+  if (minISize.ConvertsToLength() || nsIFrame::ToExtremumLength(minISize)) {
+    nscoord c = aFrame
+                    ->ComputeISizeValue(aRenderingContext, aWM, zeroSize,
+                                        zeroSize, 0, minISize)
+                    .mISize;
+    minCoord = std::max(c, minCoord);
+    prefCoord = std::max(c, prefCoord);
+  } else if (minISize.ConvertsToPercentage()) {
+    float p = minISize.ToPercentage();
+    if (p > prefPercent) {
+      prefPercent = p;
+    }
+  }
+
+  // XXX Should col frame have border/padding considered?
+  if (aIsCell) {
+    minCoord += boxSizingToBorderEdge;
+    prefCoord = NSCoordSaturatingAdd(prefCoord, boxSizingToBorderEdge);
+  }
+
+  return CellISizeInfo(minCoord, prefCoord, prefPercent, hasSpecifiedISize);
+}
+
+static inline CellISizeInfo GetCellISizeInfo(gfxContext* aRenderingContext,
+                                             nsTableCellFrame* aCellFrame,
+                                             WritingMode aWM) {
+  return GetISizeInfo(aRenderingContext, aCellFrame, aWM, true);
+}
+
+static inline CellISizeInfo GetColISizeInfo(gfxContext* aRenderingContext,
+                                            nsIFrame* aFrame, WritingMode aWM) {
+  return GetISizeInfo(aRenderingContext, aFrame, aWM, false);
+}
+
+/**
+ * The algorithm in this function, in addition to meeting the
+ * requirements of Web-compatibility, is also invariant under reordering
+ * of the rows within a table (something that most, but not all, other
+ * browsers are).
+ */
+void BasicTableLayoutStrategy::ComputeColumnIntrinsicISizes(
+    gfxContext* aRenderingContext) {
+  nsTableFrame* tableFrame = mTableFrame;
+  nsTableCellMap* cellMap = tableFrame->GetCellMap();
+  WritingMode wm = tableFrame->GetWritingMode();
+
+  mozilla::AutoStackArena arena;
+  SpanningCellSorter spanningCells;
+
+  // Loop over the columns to consider the columns and cells *without*
+  // a colspan.
+  int32_t col, col_end;
+  for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
+    nsTableColFrame* colFrame = tableFrame->GetColFrame(col);
+    if (!colFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+    colFrame->ResetIntrinsics();
+    colFrame->ResetSpanIntrinsics();
+
+    // Consider the isizes on the column.
+    CellISizeInfo colInfo = GetColISizeInfo(aRenderingContext, colFrame, wm);
+    colFrame->AddCoords(colInfo.minCoord, colInfo.prefCoord,
+                        colInfo.hasSpecifiedISize);
+    colFrame->AddPrefPercent(colInfo.prefPercent);
+
+    // Consider the isizes on the column-group.  Note that we follow
+    // what the HTML spec says here, and make the isize apply to
+    // each column in the group, not the group as a whole.
+
+    // If column has isize, column-group doesn't override isize.
+    if (colInfo.minCoord == 0 && colInfo.prefCoord == 0 &&
+        colInfo.prefPercent == 0.0f) {
+      NS_ASSERTION(colFrame->GetParent()->IsTableColGroupFrame(),
+                   "expected a column-group");
+      colInfo = GetColISizeInfo(aRenderingContext, colFrame->GetParent(), wm);
+      colFrame->AddCoords(colInfo.minCoord, colInfo.prefCoord,
+                          colInfo.hasSpecifiedISize);
+      colFrame->AddPrefPercent(colInfo.prefPercent);
+    }
+
+    // Consider the contents of and the isizes on the cells without
+    // colspans.
+    nsCellMapColumnIterator columnIter(cellMap, col);
+    int32_t row, colSpan;
+    nsTableCellFrame* cellFrame;
+    while ((cellFrame = columnIter.GetNextFrame(&row, &colSpan))) {
+      if (colSpan > 1) {
+        spanningCells.AddCell(colSpan, row, col);
+        continue;
+      }
+
+      CellISizeInfo info = GetCellISizeInfo(aRenderingContext, cellFrame, wm);
+
+      colFrame->AddCoords(info.minCoord, info.prefCoord,
+                          info.hasSpecifiedISize);
+      colFrame->AddPrefPercent(info.prefPercent);
+    }
+#ifdef DEBUG_dbaron_off
+    printf("table %p col %d nonspan: min=%d pref=%d spec=%d pct=%f\n",
+           mTableFrame, col, colFrame->GetMinCoord(), colFrame->GetPrefCoord(),
+           colFrame->GetHasSpecifiedCoord(), colFrame->GetPrefPercent());
+#endif
+  }
+#ifdef DEBUG_TABLE_STRATEGY
+  printf("ComputeColumnIntrinsicISizes single\n");
+  mTableFrame->Dump(false, true, false);
+#endif
+
+  // Consider the cells with a colspan that we saved in the loop above
+  // into the spanning cell sorter.  We consider these cells by seeing
+  // if they require adding to the isizes resulting only from cells
+  // with a smaller colspan, and therefore we must process them sorted
+  // in increasing order by colspan.  For each colspan group, we
+  // accumulate new values to accumulate in the column frame's Span*
+  // members.
+  //
+  // Considering things only relative to the isizes resulting from
+  // cells with smaller colspans (rather than incrementally including
+  // the results from spanning cells, or doing spanning and
+  // non-spanning cells in a single pass) means that layout remains
+  // row-order-invariant and (except for percentage isizes that add to
+  // more than 100%) column-order invariant.
+  //
+  // Starting with smaller colspans makes it more likely that we
+  // satisfy all the constraints given and don't distribute space to
+  // columns where we don't need it.
+  SpanningCellSorter::Item* item;
+  int32_t colSpan;
+  while ((item = spanningCells.GetNext(&colSpan))) {
+    NS_ASSERTION(colSpan > 1,
+                 "cell should not have been put in spanning cell sorter");
+    do {
+      int32_t row = item->row;
+      col = item->col;
+      CellData* cellData = cellMap->GetDataAt(row, col);
+      NS_ASSERTION(cellData && cellData->IsOrig(),
+                   "bogus result from spanning cell sorter");
+
+      nsTableCellFrame* cellFrame = cellData->GetCellFrame();
+      NS_ASSERTION(cellFrame, "bogus result from spanning cell sorter");
+
+      CellISizeInfo info = GetCellISizeInfo(aRenderingContext, cellFrame, wm);
+
+      if (info.prefPercent > 0.0f) {
+        DistributePctISizeToColumns(info.prefPercent, col, colSpan);
+      }
+      DistributeISizeToColumns(info.minCoord, col, colSpan, BTLS_MIN_ISIZE,
+                               info.hasSpecifiedISize);
+      DistributeISizeToColumns(info.prefCoord, col, colSpan, BTLS_PREF_ISIZE,
+                               info.hasSpecifiedISize);
+    } while ((item = item->next));
+
+    // Combine the results of the span analysis into the main results,
+    // for each increment of colspan.
+
+    for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
+      nsTableColFrame* colFrame = tableFrame->GetColFrame(col);
+      if (!colFrame) {
+        NS_ERROR("column frames out of sync with cell map");
+        continue;
+      }
+
+      colFrame->AccumulateSpanIntrinsics();
+      colFrame->ResetSpanIntrinsics();
+
+#ifdef DEBUG_dbaron_off
+      printf("table %p col %d span %d: min=%d pref=%d spec=%d pct=%f\n",
+             mTableFrame, col, colSpan, colFrame->GetMinCoord(),
+             colFrame->GetPrefCoord(), colFrame->GetHasSpecifiedCoord(),
+             colFrame->GetPrefPercent());
+#endif
+    }
+  }
+
+  // Prevent percentages from adding to more than 100% by (to be
+  // compatible with other browsers) treating any percentages that would
+  // increase the total percentage to more than 100% as the number that
+  // would increase it to only 100% (which is 0% if we've already hit
+  // 100%).  This means layout depends on the order of columns.
+  float pct_used = 0.0f;
+  for (col = 0, col_end = cellMap->GetColCount(); col < col_end; ++col) {
+    nsTableColFrame* colFrame = tableFrame->GetColFrame(col);
+    if (!colFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+
+    colFrame->AdjustPrefPercent(&pct_used);
+  }
+
+#ifdef DEBUG_TABLE_STRATEGY
+  printf("ComputeColumnIntrinsicISizes spanning\n");
+  mTableFrame->Dump(false, true, false);
+#endif
+}
+
+void BasicTableLayoutStrategy::ComputeIntrinsicISizes(
+    gfxContext* aRenderingContext) {
+  ComputeColumnIntrinsicISizes(aRenderingContext);
+
+  nsTableCellMap* cellMap = mTableFrame->GetCellMap();
+  nscoord min = 0, pref = 0, max_small_pct_pref = 0, nonpct_pref_total = 0;
+  float pct_total = 0.0f;  // always from 0.0f - 1.0f
+  int32_t colCount = cellMap->GetColCount();
+  // add a total of (colcount + 1) lots of cellSpacingX for columns where a
+  // cell originates
+  nscoord add = mTableFrame->GetColSpacing(colCount);
+
+  for (int32_t col = 0; col < colCount; ++col) {
+    nsTableColFrame* colFrame = mTableFrame->GetColFrame(col);
+    if (!colFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+    if (mTableFrame->ColumnHasCellSpacingBefore(col)) {
+      add += mTableFrame->GetColSpacing(col - 1);
+    }
+    min += colFrame->GetMinCoord();
+    pref = NSCoordSaturatingAdd(pref, colFrame->GetPrefCoord());
+
+    // Percentages are of the table, so we have to reverse them for
+    // intrinsic isizes.
+    float p = colFrame->GetPrefPercent();
+    if (p > 0.0f) {
+      nscoord colPref = colFrame->GetPrefCoord();
+      nscoord new_small_pct_expand =
+          (colPref == nscoord_MAX ? nscoord_MAX : nscoord(float(colPref) / p));
+      if (new_small_pct_expand > max_small_pct_pref) {
+        max_small_pct_pref = new_small_pct_expand;
+      }
+      pct_total += p;
+    } else {
+      nonpct_pref_total =
+          NSCoordSaturatingAdd(nonpct_pref_total, colFrame->GetPrefCoord());
+    }
+  }
+
+  nscoord pref_pct_expand = pref;
+
+  // Account for small percentages expanding the preferred isize of
+  // *other* columns.
+  if (max_small_pct_pref > pref_pct_expand) {
+    pref_pct_expand = max_small_pct_pref;
+  }
+
+  // Account for large percentages expanding the preferred isize of
+  // themselves.  There's no need to iterate over the columns multiple
+  // times, since when there is such a need, the small percentage
+  // effect is bigger anyway.  (I think!)
+  NS_ASSERTION(0.0f <= pct_total && pct_total <= 1.0f,
+               "column percentage inline-sizes not adjusted down to 100%");
+  if (pct_total == 1.0f) {
+    if (nonpct_pref_total > 0) {
+      pref_pct_expand = nscoord_MAX;
+      // XXX Or should I use some smaller value?  (Test this using
+      // nested tables!)
+    }
+  } else {
+    nscoord large_pct_pref =
+        (nonpct_pref_total == nscoord_MAX
+             ? nscoord_MAX
+             : nscoord(float(nonpct_pref_total) / (1.0f - pct_total)));
+    if (large_pct_pref > pref_pct_expand) pref_pct_expand = large_pct_pref;
+  }
+
+  // border-spacing isn't part of the basis for percentages
+  if (colCount > 0) {
+    min += add;
+    pref = NSCoordSaturatingAdd(pref, add);
+    pref_pct_expand = NSCoordSaturatingAdd(pref_pct_expand, add);
+  }
+
+  mMinISize = min;
+  mPrefISize = pref;
+  mPrefISizePctExpand = pref_pct_expand;
+}
+
+/* virtual */
+void BasicTableLayoutStrategy::MarkIntrinsicISizesDirty() {
+  mMinISize = NS_INTRINSIC_ISIZE_UNKNOWN;
+  mPrefISize = NS_INTRINSIC_ISIZE_UNKNOWN;
+  mPrefISizePctExpand = NS_INTRINSIC_ISIZE_UNKNOWN;
+  mLastCalcISize = nscoord_MIN;
+}
+
+/* virtual */
+void BasicTableLayoutStrategy::ComputeColumnISizes(
+    const ReflowInput& aReflowInput) {
+  nscoord iSize = aReflowInput.ComputedISize();
+
+  if (mLastCalcISize == iSize) {
+    return;
+  }
+  mLastCalcISize = iSize;
+
+  NS_ASSERTION((mMinISize == NS_INTRINSIC_ISIZE_UNKNOWN) ==
+                   (mPrefISize == NS_INTRINSIC_ISIZE_UNKNOWN),
+               "dirtyness out of sync");
+  NS_ASSERTION((mMinISize == NS_INTRINSIC_ISIZE_UNKNOWN) ==
+                   (mPrefISizePctExpand == NS_INTRINSIC_ISIZE_UNKNOWN),
+               "dirtyness out of sync");
+  // XXX Is this needed?
+  if (mMinISize == NS_INTRINSIC_ISIZE_UNKNOWN) {
+    ComputeIntrinsicISizes(aReflowInput.mRenderingContext);
+  }
+
+  nsTableCellMap* cellMap = mTableFrame->GetCellMap();
+  int32_t colCount = cellMap->GetColCount();
+  if (colCount <= 0) return;  // nothing to do
+
+  DistributeISizeToColumns(iSize, 0, colCount, BTLS_FINAL_ISIZE, false);
+
+#ifdef DEBUG_TABLE_STRATEGY
+  printf("ComputeColumnISizes final\n");
+  mTableFrame->Dump(false, true, false);
+#endif
+}
+
+void BasicTableLayoutStrategy::DistributePctISizeToColumns(float aSpanPrefPct,
+                                                           int32_t aFirstCol,
+                                                           int32_t aColCount) {
+  // First loop to determine:
+  int32_t nonPctColCount = 0;  // number of spanned columns without % isize
+  nscoord nonPctTotalPrefISize = 0;  // total pref isize of those columns
+  // and to reduce aSpanPrefPct by columns that already have % isize
+
+  int32_t scol, scol_end;
+  nsTableCellMap* cellMap = mTableFrame->GetCellMap();
+  for (scol = aFirstCol, scol_end = aFirstCol + aColCount; scol < scol_end;
+       ++scol) {
+    nsTableColFrame* scolFrame = mTableFrame->GetColFrame(scol);
+    if (!scolFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+    float scolPct = scolFrame->GetPrefPercent();
+    if (scolPct == 0.0f) {
+      nonPctTotalPrefISize += scolFrame->GetPrefCoord();
+      if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
+        ++nonPctColCount;
+      }
+    } else {
+      aSpanPrefPct -= scolPct;
+    }
+  }
+
+  if (aSpanPrefPct <= 0.0f || nonPctColCount == 0) {
+    // There's no %-isize on the colspan left over to distribute,
+    // or there are no columns to which we could distribute %-isize
+    return;
+  }
+
+  // Second loop, to distribute what remains of aSpanPrefPct
+  // between the non-percent-isize spanned columns
+  const bool spanHasNonPctPref = nonPctTotalPrefISize > 0;  // Loop invariant
+  for (scol = aFirstCol, scol_end = aFirstCol + aColCount; scol < scol_end;
+       ++scol) {
+    nsTableColFrame* scolFrame = mTableFrame->GetColFrame(scol);
+    if (!scolFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+
+    if (scolFrame->GetPrefPercent() == 0.0f) {
+      NS_ASSERTION((!spanHasNonPctPref || nonPctTotalPrefISize != 0) &&
+                       nonPctColCount != 0,
+                   "should not be zero if we haven't allocated "
+                   "all pref percent");
+
+      float allocatedPct;  // % isize to be given to this column
+      if (spanHasNonPctPref) {
+        // Group so we're multiplying by 1.0f when we need
+        // to use up aSpanPrefPct.
+        allocatedPct = aSpanPrefPct * (float(scolFrame->GetPrefCoord()) /
+                                       float(nonPctTotalPrefISize));
+      } else if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
+        // distribute equally when all pref isizes are 0
+        allocatedPct = aSpanPrefPct / float(nonPctColCount);
+      } else {
+        allocatedPct = 0.0f;
+      }
+      // Allocate the percent
+      scolFrame->AddSpanPrefPercent(allocatedPct);
+
+      // To avoid accumulating rounding error from division,
+      // subtract this column's values from the totals.
+      aSpanPrefPct -= allocatedPct;
+      nonPctTotalPrefISize -= scolFrame->GetPrefCoord();
+      if (cellMap->GetNumCellsOriginatingInCol(scol) > 0) {
+        --nonPctColCount;
+      }
+
+      if (!aSpanPrefPct) {
+        // No more span-percent-isize to distribute --> we're done.
+        NS_ASSERTION(
+            spanHasNonPctPref ? nonPctTotalPrefISize == 0 : nonPctColCount == 0,
+            "No more pct inline-size to distribute, "
+            "but there are still cols that need some.");
+        return;
+      }
+    }
+  }
+}
+
+void BasicTableLayoutStrategy::DistributeISizeToColumns(
+    nscoord aISize, int32_t aFirstCol, int32_t aColCount,
+    BtlsISizeType aISizeType, bool aSpanHasSpecifiedISize) {
+  NS_ASSERTION(
+      aISizeType != BTLS_FINAL_ISIZE ||
+          (aFirstCol == 0 &&
+           aColCount == mTableFrame->GetCellMap()->GetColCount()),
+      "Computing final column isizes, but didn't get full column range");
+
+  nscoord subtract = 0;
+  // aISize initially includes border-spacing for the boundaries in between
+  // each of the columns. We start at aFirstCol + 1 because the first
+  // in-between boundary would be at the left edge of column aFirstCol + 1
+  for (int32_t col = aFirstCol + 1; col < aFirstCol + aColCount; ++col) {
+    if (mTableFrame->ColumnHasCellSpacingBefore(col)) {
+      // border-spacing isn't part of the basis for percentages.
+      subtract += mTableFrame->GetColSpacing(col - 1);
+    }
+  }
+  if (aISizeType == BTLS_FINAL_ISIZE) {
+    // If we're computing final col-isize, then aISize initially includes
+    // border spacing on the table's far istart + far iend edge, too.  Need
+    // to subtract those out, too.
+    subtract += (mTableFrame->GetColSpacing(-1) +
+                 mTableFrame->GetColSpacing(aColCount));
+  }
+  aISize = NSCoordSaturatingSubtract(aISize, subtract, nscoord_MAX);
+
+  /*
+   * The goal of this function is to distribute |aISize| between the
+   * columns by making an appropriate AddSpanCoords or SetFinalISize
+   * call for each column.  (We call AddSpanCoords if we're
+   * distributing a column-spanning cell's minimum or preferred isize
+   * to its spanned columns.  We call SetFinalISize if we're
+   * distributing a table's final isize to its columns.)
+   *
+   * The idea is to either assign one of the following sets of isizes
+   * or a weighted average of two adjacent sets of isizes.  It is not
+   * possible to assign values smaller than the smallest set of
+   * isizes.  However, see below for handling the case of assigning
+   * values larger than the largest set of isizes.  From smallest to
+   * largest, these are:
+   *
+   * 1. [guess_min] Assign all columns their min isize.
+   *
+   * 2. [guess_min_pct] Assign all columns with percentage isizes
+   * their percentage isize, and all other columns their min isize.
+   *
+   * 3. [guess_min_spec] Assign all columns with percentage isizes
+   * their percentage isize, all columns with specified coordinate
+   * isizes their pref isize (since it doesn't matter whether it's the
+   * largest contributor to the pref isize that was the specified
+   * contributor), and all other columns their min isize.
+   *
+   * 4. [guess_pref] Assign all columns with percentage isizes their
+   * specified isize, and all other columns their pref isize.
+   *
+   * If |aISize| is *larger* than what we would assign in (4), then we
+   * expand the columns:
+   *
+   *   a. if any columns without a specified coordinate isize or
+   *   percent isize have nonzero pref isize, in proportion to pref
+   *   isize [total_flex_pref]
+   *
+   *   b. otherwise, if any columns without a specified coordinate
+   *   isize or percent isize, but with cells originating in them,
+   *   have zero pref isize, equally between these
+   *   [numNonSpecZeroISizeCols]
+   *
+   *   c. otherwise, if any columns without percent isize have nonzero
+   *   pref isize, in proportion to pref isize [total_fixed_pref]
+   *
+   *   d. otherwise, if any columns have nonzero percentage isizes, in
+   *   proportion to the percentage isizes [total_pct]
+   *
+   *   e. otherwise, equally.
+   */
+
+  // Loop #1 over the columns, to figure out the four values above so
+  // we know which case we're dealing with.
+
+  nscoord guess_min = 0, guess_min_pct = 0, guess_min_spec = 0, guess_pref = 0,
+          total_flex_pref = 0, total_fixed_pref = 0;
+  float total_pct = 0.0f;  // 0.0f to 1.0f
+  int32_t numInfiniteISizeCols = 0;
+  int32_t numNonSpecZeroISizeCols = 0;
+
+  int32_t col;
+  nsTableCellMap* cellMap = mTableFrame->GetCellMap();
+  for (col = aFirstCol; col < aFirstCol + aColCount; ++col) {
+    nsTableColFrame* colFrame = mTableFrame->GetColFrame(col);
+    if (!colFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+    nscoord min_iSize = colFrame->GetMinCoord();
+    guess_min += min_iSize;
+    if (colFrame->GetPrefPercent() != 0.0f) {
+      float pct = colFrame->GetPrefPercent();
+      total_pct += pct;
+      nscoord val = nscoord(float(aISize) * pct);
+      if (val < min_iSize) {
+        val = min_iSize;
+      }
+      guess_min_pct = NSCoordSaturatingAdd(guess_min_pct, val);
+      guess_pref = NSCoordSaturatingAdd(guess_pref, val);
+    } else {
+      nscoord pref_iSize = colFrame->GetPrefCoord();
+      if (pref_iSize == nscoord_MAX) {
+        ++numInfiniteISizeCols;
+      }
+      guess_pref = NSCoordSaturatingAdd(guess_pref, pref_iSize);
+      guess_min_pct = NSCoordSaturatingAdd(guess_min_pct, min_iSize);
+      if (colFrame->GetHasSpecifiedCoord()) {
+        // we'll add on the rest of guess_min_spec outside the
+        // loop
+        nscoord delta = NSCoordSaturatingSubtract(pref_iSize, min_iSize, 0);
+        guess_min_spec = NSCoordSaturatingAdd(guess_min_spec, delta);
+        total_fixed_pref = NSCoordSaturatingAdd(total_fixed_pref, pref_iSize);
+      } else if (pref_iSize == 0) {
+        if (cellMap->GetNumCellsOriginatingInCol(col) > 0) {
+          ++numNonSpecZeroISizeCols;
+        }
+      } else {
+        total_flex_pref = NSCoordSaturatingAdd(total_flex_pref, pref_iSize);
+      }
+    }
+  }
+  guess_min_spec = NSCoordSaturatingAdd(guess_min_spec, guess_min_pct);
+
+  // Determine what we're flexing:
+  enum Loop2Type {
+    FLEX_PCT_SMALL,        // between (1) and (2) above
+    FLEX_FIXED_SMALL,      // between (2) and (3) above
+    FLEX_FLEX_SMALL,       // between (3) and (4) above
+    FLEX_FLEX_LARGE,       // greater than (4) above, case (a)
+    FLEX_FLEX_LARGE_ZERO,  // greater than (4) above, case (b)
+    FLEX_FIXED_LARGE,      // greater than (4) above, case (c)
+    FLEX_PCT_LARGE,        // greater than (4) above, case (d)
+    FLEX_ALL_LARGE         // greater than (4) above, case (e)
+  };
+
+  Loop2Type l2t;
+  // These are constants (over columns) for each case's math.  We use
+  // a pair of nscoords rather than a float so that we can subtract
+  // each column's allocation so we avoid accumulating rounding error.
+  nscoord space;  // the amount of extra isize to allocate
+  union {
+    nscoord c;
+    float f;
+  } basis;  // the sum of the statistic over columns to divide it
+  if (aISize < guess_pref) {
+    if (aISizeType != BTLS_FINAL_ISIZE && aISize <= guess_min) {
+      // Return early -- we don't have any extra space to distribute.
+      return;
+    }
+    NS_ASSERTION(!(aISizeType == BTLS_FINAL_ISIZE && aISize < guess_min),
+                 "Table inline-size is less than the "
+                 "sum of its columns' min inline-sizes");
+    if (aISize < guess_min_pct) {
+      l2t = FLEX_PCT_SMALL;
+      space = aISize - guess_min;
+      basis.c = guess_min_pct - guess_min;
+    } else if (aISize < guess_min_spec) {
+      l2t = FLEX_FIXED_SMALL;
+      space = aISize - guess_min_pct;
+      basis.c =
+          NSCoordSaturatingSubtract(guess_min_spec, guess_min_pct, nscoord_MAX);
+    } else {
+      l2t = FLEX_FLEX_SMALL;
+      space = aISize - guess_min_spec;
+      basis.c =
+          NSCoordSaturatingSubtract(guess_pref, guess_min_spec, nscoord_MAX);
+    }
+  } else {
+    space = NSCoordSaturatingSubtract(aISize, guess_pref, nscoord_MAX);
+    if (total_flex_pref > 0) {
+      l2t = FLEX_FLEX_LARGE;
+      basis.c = total_flex_pref;
+    } else if (numNonSpecZeroISizeCols > 0) {
+      l2t = FLEX_FLEX_LARGE_ZERO;
+      basis.c = numNonSpecZeroISizeCols;
+    } else if (total_fixed_pref > 0) {
+      l2t = FLEX_FIXED_LARGE;
+      basis.c = total_fixed_pref;
+    } else if (total_pct > 0.0f) {
+      l2t = FLEX_PCT_LARGE;
+      basis.f = total_pct;
+    } else {
+      l2t = FLEX_ALL_LARGE;
+      basis.c = aColCount;
+    }
+  }
+
+#ifdef DEBUG_dbaron_off
+  printf(
+      "ComputeColumnISizes: %d columns in isize %d,\n"
+      "  guesses=[%d,%d,%d,%d], totals=[%d,%d,%f],\n"
+      "  l2t=%d, space=%d, basis.c=%d\n",
+      aColCount, aISize, guess_min, guess_min_pct, guess_min_spec, guess_pref,
+      total_flex_pref, total_fixed_pref, total_pct, l2t, space, basis.c);
+#endif
+
+  for (col = aFirstCol; col < aFirstCol + aColCount; ++col) {
+    nsTableColFrame* colFrame = mTableFrame->GetColFrame(col);
+    if (!colFrame) {
+      NS_ERROR("column frames out of sync with cell map");
+      continue;
+    }
+    nscoord col_iSize;
+
+    float pct = colFrame->GetPrefPercent();
+    if (pct != 0.0f) {
+      col_iSize = nscoord(float(aISize) * pct);
+      nscoord col_min = colFrame->GetMinCoord();
+      if (col_iSize < col_min) {
+        col_iSize = col_min;
+      }
+    } else {
+      col_iSize = colFrame->GetPrefCoord();
+    }
+
+    nscoord col_iSize_before_adjust = col_iSize;
+
+    switch (l2t) {
+      case FLEX_PCT_SMALL:
+        col_iSize = col_iSize_before_adjust = colFrame->GetMinCoord();
+        if (pct != 0.0f) {
+          nscoord pct_minus_min = nscoord(float(aISize) * pct) - col_iSize;
+          if (pct_minus_min > 0) {
+            float c = float(space) / float(basis.c);
+            basis.c -= pct_minus_min;
+            col_iSize = NSCoordSaturatingAdd(
+                col_iSize, NSToCoordRound(float(pct_minus_min) * c));
+          }
+        }
+        break;
+      case FLEX_FIXED_SMALL:
+        if (pct == 0.0f) {
+          NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
+                       "wrong inline-size assigned");
+          if (colFrame->GetHasSpecifiedCoord()) {
+            nscoord col_min = colFrame->GetMinCoord();
+            nscoord pref_minus_min = col_iSize - col_min;
+            col_iSize = col_iSize_before_adjust = col_min;
+            if (pref_minus_min != 0) {
+              float c = float(space) / float(basis.c);
+              basis.c -= pref_minus_min;
+              col_iSize = NSCoordSaturatingAdd(
+                  col_iSize, NSToCoordRound(float(pref_minus_min) * c));
+            }
+          } else
+            col_iSize = col_iSize_before_adjust = colFrame->GetMinCoord();
+        }
+        break;
+      case FLEX_FLEX_SMALL:
+        if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord()) {
+          NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
+                       "wrong inline-size assigned");
+          nscoord col_min = colFrame->GetMinCoord();
+          nscoord pref_minus_min =
+              NSCoordSaturatingSubtract(col_iSize, col_min, 0);
+          col_iSize = col_iSize_before_adjust = col_min;
+          if (pref_minus_min != 0) {
+            float c = float(space) / float(basis.c);
+            // If we have infinite-isize cols, then the standard
+            // adjustment to col_iSize using 'c' won't work,
+            // because basis.c and pref_minus_min are both
+            // nscoord_MAX and will cancel each other out in the
+            // col_iSize adjustment (making us assign all the
+            // space to the first inf-isize col).  To correct for
+            // this, we'll also divide by numInfiniteISizeCols to
+            // spread the space equally among the inf-isize cols.
+            if (numInfiniteISizeCols) {
+              if (colFrame->GetPrefCoord() == nscoord_MAX) {
+                c = c / float(numInfiniteISizeCols);
+                --numInfiniteISizeCols;
+              } else {
+                c = 0.0f;
+              }
+            }
+            basis.c =
+                NSCoordSaturatingSubtract(basis.c, pref_minus_min, nscoord_MAX);
+            col_iSize = NSCoordSaturatingAdd(
+                col_iSize, NSToCoordRound(float(pref_minus_min) * c));
+          }
+        }
+        break;
+      case FLEX_FLEX_LARGE:
+        if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord()) {
+          NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
+                       "wrong inline-size assigned");
+          if (col_iSize != 0) {
+            if (space == nscoord_MAX) {
+              basis.c -= col_iSize;
+              col_iSize = nscoord_MAX;
+            } else {
+              float c = float(space) / float(basis.c);
+              basis.c -= col_iSize;
+              col_iSize = NSCoordSaturatingAdd(
+                  col_iSize, NSToCoordRound(float(col_iSize) * c));
+            }
+          }
+        }
+        break;
+      case FLEX_FLEX_LARGE_ZERO:
+        if (pct == 0.0f && !colFrame->GetHasSpecifiedCoord() &&
+            cellMap->GetNumCellsOriginatingInCol(col) > 0) {
+          NS_ASSERTION(col_iSize == 0 && colFrame->GetPrefCoord() == 0,
+                       "Since we're in FLEX_FLEX_LARGE_ZERO case, "
+                       "all auto-inline-size cols should have zero "
+                       "pref inline-size.");
+          float c = float(space) / float(basis.c);
+          col_iSize += NSToCoordRound(c);
+          --basis.c;
+        }
+        break;
+      case FLEX_FIXED_LARGE:
+        if (pct == 0.0f) {
+          NS_ASSERTION(col_iSize == colFrame->GetPrefCoord(),
+                       "wrong inline-size assigned");
+          NS_ASSERTION(
+              colFrame->GetHasSpecifiedCoord() || colFrame->GetPrefCoord() == 0,
+              "wrong case");
+          if (col_iSize != 0) {
+            float c = float(space) / float(basis.c);
+            basis.c -= col_iSize;
+            col_iSize = NSCoordSaturatingAdd(
+                col_iSize, NSToCoordRound(float(col_iSize) * c));
+          }
+        }
+        break;
+      case FLEX_PCT_LARGE:
+        NS_ASSERTION(pct != 0.0f || colFrame->GetPrefCoord() == 0,
+                     "wrong case");
+        if (pct != 0.0f) {
+          float c = float(space) / basis.f;
+          col_iSize = NSCoordSaturatingAdd(col_iSize, NSToCoordRound(pct * c));
+          basis.f -= pct;
+        }
+        break;
+      case FLEX_ALL_LARGE: {
+        float c = float(space) / float(basis.c);
+        col_iSize = NSCoordSaturatingAdd(col_iSize, NSToCoordRound(c));
+        --basis.c;
+      } break;
+    }
+
+    // Only subtract from space if it's a real number.
+    if (space != nscoord_MAX) {
+      NS_ASSERTION(col_iSize != nscoord_MAX,
+                   "How is col_iSize nscoord_MAX if space isn't?");
+      NS_ASSERTION(
+          col_iSize_before_adjust != nscoord_MAX,
+          "How is col_iSize_before_adjust nscoord_MAX if space isn't?");
+      space -= col_iSize - col_iSize_before_adjust;
+    }
+
+    NS_ASSERTION(col_iSize >= colFrame->GetMinCoord(),
+                 "assigned inline-size smaller than min");
+
+    // Apply the new isize
+    switch (aISizeType) {
+      case BTLS_MIN_ISIZE: {
+        // Note: AddSpanCoords requires both a min and pref isize.
+        // For the pref isize, we'll just pass in our computed
+        // min isize, because the real pref isize will be at least
+        // as big
+        colFrame->AddSpanCoords(col_iSize, col_iSize, aSpanHasSpecifiedISize);
+      } break;
+      case BTLS_PREF_ISIZE: {
+        // Note: AddSpanCoords requires both a min and pref isize.
+        // For the min isize, we'll just pass in 0, because
+        // the real min isize will be at least 0
+        colFrame->AddSpanCoords(0, col_iSize, aSpanHasSpecifiedISize);
+      } break;
+      case BTLS_FINAL_ISIZE: {
+        nscoord old_final = colFrame->GetFinalISize();
+        colFrame->SetFinalISize(col_iSize);
+
+        if (old_final != col_iSize) {
+          mTableFrame->DidResizeColumns();
+        }
+      } break;
+    }
+  }
+  NS_ASSERTION(
+      (space == 0 || space == nscoord_MAX) &&
+          ((l2t == FLEX_PCT_LARGE) ? (-0.001f < basis.f && basis.f < 0.001f)
+                                   : (basis.c == 0 || basis.c == nscoord_MAX)),
+      "didn't subtract all that we added");
+}