Index: clang/lib/Format/UnwrappedLineFormatter.cpp
===================================================================
--- clang/lib/Format/UnwrappedLineFormatter.cpp
+++ clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -211,10 +211,11 @@
     const AnnotatedLine *TheLine = *I;
     if (TheLine->Last->is(TT_LineComment))
       return 0;
-    if (I[1]->Type == LT_Invalid || I[1]->First->MustBreakBefore)
+    const auto &NextLine = *I[1];
+    if (NextLine.Type == LT_Invalid || NextLine.First->MustBreakBefore)
       return 0;
     if (TheLine->InPPDirective &&
-        (!I[1]->InPPDirective || I[1]->First->HasUnescapedNewline))
+        (!NextLine.InPPDirective || NextLine.First->HasUnescapedNewline))
       return 0;
 
     if (Style.ColumnLimit > 0 && Indent > Style.ColumnLimit)
@@ -231,43 +232,15 @@
     if (TheLine->Last->is(TT_FunctionLBrace) &&
         TheLine->First == TheLine->Last &&
         !Style.BraceWrapping.SplitEmptyFunction &&
-        I[1]->First->is(tok::r_brace))
+        NextLine.First->is(tok::r_brace))
       return tryMergeSimpleBlock(I, E, Limit);
 
-    // Handle empty record blocks where the brace has already been wrapped
-    if (TheLine->Last->is(tok::l_brace) && TheLine->First == TheLine->Last &&
-        I != AnnotatedLines.begin()) {
-      bool EmptyBlock = I[1]->First->is(tok::r_brace);
-
-      const FormatToken *Tok = I[-1]->First;
-      if (Tok && Tok->is(tok::comment))
-        Tok = Tok->getNextNonComment();
-
-      if (Tok && Tok->getNamespaceToken())
-        return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock
-                   ? tryMergeSimpleBlock(I, E, Limit)
-                   : 0;
-
-      if (Tok && Tok->is(tok::kw_typedef))
-        Tok = Tok->getNextNonComment();
-      if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
-                              tok::kw_extern, Keywords.kw_interface))
-        return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
-                   ? tryMergeSimpleBlock(I, E, Limit)
-                   : 0;
-
-      if (Tok && Tok->is(tok::kw_template) &&
-          Style.BraceWrapping.SplitEmptyRecord && EmptyBlock) {
-        return 0;
-      }
-    }
-
     // FIXME: TheLine->Level != 0 might or might not be the right check to do.
     // If necessary, change to something smarter.
     bool MergeShortFunctions =
         Style.AllowShortFunctionsOnASingleLine == FormatStyle::SFS_All ||
         (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
-         I[1]->First->is(tok::r_brace)) ||
+         NextLine.First->is(tok::r_brace)) ||
         (Style.AllowShortFunctionsOnASingleLine & FormatStyle::SFS_InlineOnly &&
          TheLine->Level != 0);
 
@@ -280,7 +253,7 @@
                closingLine == I[i + 1]->MatchingClosingBlockLineIndex &&
                I[i + 1]->Last->TotalLength < Limit;
              i++, closingLine--) {
-          // No extra indent for compacted namespaces
+          // No extra indent for compacted namespaces.
           IndentTracker.skipLine(*I[i + 1]);
 
           Limit -= I[i + 1]->Last->TotalLength;
@@ -296,102 +269,134 @@
                    getMatchingNamespaceTokenText(I[i + 1], AnnotatedLines) &&
                openingLine == I[i + 1]->MatchingOpeningBlockLineIndex;
              i++, openingLine--) {
-          // No space between consecutive braces
+          // No space between consecutive braces.
           I[i + 1]->First->SpacesRequiredBefore = !I[i]->Last->is(tok::r_brace);
 
-          // Indent like the outer-most namespace
+          // Indent like the outer-most namespace.
           IndentTracker.nextLine(*I[i + 1]);
         }
         return i;
       }
     }
 
-    // Try to merge a function block with left brace unwrapped
+    // Try to merge a function block with left brace unwrapped.
     if (TheLine->Last->is(TT_FunctionLBrace) &&
         TheLine->First != TheLine->Last) {
       return MergeShortFunctions ? tryMergeSimpleBlock(I, E, Limit) : 0;
     }
-    // Try to merge a control statement block with left brace unwrapped
-    if (TheLine->Last->is(tok::l_brace) && TheLine->First != TheLine->Last &&
+    // Try to merge a control statement block with left brace unwrapped.
+    if (TheLine->Last->is(tok::l_brace) &&
         TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for)) {
       return Style.AllowShortBlocksOnASingleLine != FormatStyle::SBS_Never
                  ? tryMergeSimpleBlock(I, E, Limit)
                  : 0;
     }
-    // Try to merge a control statement block with left brace wrapped
-    if (I[1]->First->is(tok::l_brace) &&
-        (TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
-                                 tok::kw_for, tok::kw_switch, tok::kw_try,
-                                 tok::kw_do, TT_ForEachMacro) ||
-         (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
-          TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
-        Style.BraceWrapping.AfterControlStatement ==
-            FormatStyle::BWACS_MultiLine) {
-      // If possible, merge the next line's wrapped left brace with the current
-      // line. Otherwise, leave it on the next line, as this is a multi-line
-      // control statement.
-      return (Style.ColumnLimit == 0 ||
-              TheLine->Last->TotalLength <= Style.ColumnLimit)
-                 ? 1
-                 : 0;
-    } else if (I[1]->First->is(tok::l_brace) &&
-               TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
-                                       tok::kw_for)) {
-      return (Style.BraceWrapping.AfterControlStatement ==
-              FormatStyle::BWACS_Always)
-                 ? tryMergeSimpleBlock(I, E, Limit)
-                 : 0;
-    } else if (I[1]->First->is(tok::l_brace) &&
-               TheLine->First->isOneOf(tok::kw_else, tok::kw_catch) &&
-               Style.BraceWrapping.AfterControlStatement ==
-                   FormatStyle::BWACS_MultiLine) {
-      // This case if different from the upper BWACS_MultiLine processing
-      // in that a preceding r_brace is not on the same line as else/catch
-      // most likely because of BeforeElse/BeforeCatch set to true.
-      // If the line length doesn't fit ColumnLimit, leave l_brace on the
-      // next line to respect the BWACS_MultiLine.
-      return (Style.ColumnLimit == 0 ||
-              TheLine->Last->TotalLength <= Style.ColumnLimit)
-                 ? 1
-                 : 0;
+    // Try to merge a control statement block with left brace wrapped.
+    if (NextLine.First->is(tok::l_brace)) {
+      if ((TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
+                                   tok::kw_for, tok::kw_switch, tok::kw_try,
+                                   tok::kw_do, TT_ForEachMacro) ||
+           (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
+            TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
+          Style.BraceWrapping.AfterControlStatement ==
+              FormatStyle::BWACS_MultiLine) {
+        // If possible, merge the next line's wrapped left brace with the
+        // current line. Otherwise, leave it on the next line, as this is a
+        // multi-line control statement.
+        return (Style.ColumnLimit == 0 ||
+                TheLine->Last->TotalLength <= Style.ColumnLimit)
+                   ? 1
+                   : 0;
+      }
+      if (TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
+                                  tok::kw_for)) {
+        return (Style.BraceWrapping.AfterControlStatement ==
+                FormatStyle::BWACS_Always)
+                   ? tryMergeSimpleBlock(I, E, Limit)
+                   : 0;
+      }
+      if (TheLine->First->isOneOf(tok::kw_else, tok::kw_catch) &&
+          Style.BraceWrapping.AfterControlStatement ==
+              FormatStyle::BWACS_MultiLine) {
+        // This case if different from the upper BWACS_MultiLine processing
+        // in that a preceding r_brace is not on the same line as else/catch
+        // most likely because of BeforeElse/BeforeCatch set to true.
+        // If the line length doesn't fit ColumnLimit, leave l_brace on the
+        // next line to respect the BWACS_MultiLine.
+        return (Style.ColumnLimit == 0 ||
+                TheLine->Last->TotalLength <= Style.ColumnLimit)
+                   ? 1
+                   : 0;
+      }
     }
-    // Don't merge block with left brace wrapped after ObjC special blocks
-    if (TheLine->First->is(tok::l_brace) && I != AnnotatedLines.begin() &&
-        I[-1]->First->is(tok::at) && I[-1]->First->Next) {
-      tok::ObjCKeywordKind kwId = I[-1]->First->Next->Tok.getObjCKeywordID();
-      if (kwId == clang::tok::objc_autoreleasepool ||
-          kwId == clang::tok::objc_synchronized)
+
+    if (I != AnnotatedLines.begin()){
+      const auto &PreviousLine = *I[-1];
+      // Handle empty record blocks where the brace has already been wrapped.
+      if (TheLine->Last->is(tok::l_brace) && TheLine->First == TheLine->Last) {
+        bool EmptyBlock = NextLine.First->is(tok::r_brace);
+
+        const FormatToken *Tok = PreviousLine.First;
+        if (Tok && Tok->is(tok::comment))
+          Tok = Tok->getNextNonComment();
+
+        if (Tok && Tok->getNamespaceToken())
+          return !Style.BraceWrapping.SplitEmptyNamespace && EmptyBlock
+                     ? tryMergeSimpleBlock(I, E, Limit)
+                     : 0;
+
+        if (Tok && Tok->is(tok::kw_typedef))
+          Tok = Tok->getNextNonComment();
+        if (Tok && Tok->isOneOf(tok::kw_class, tok::kw_struct, tok::kw_union,
+                                tok::kw_extern, Keywords.kw_interface))
+          return !Style.BraceWrapping.SplitEmptyRecord && EmptyBlock
+                     ? tryMergeSimpleBlock(I, E, Limit)
+                     : 0;
+
+        if (Tok && Tok->is(tok::kw_template) &&
+            Style.BraceWrapping.SplitEmptyRecord && EmptyBlock) {
+          return 0;
+        }
+      }
+
+      // Don't merge block with left brace wrapped after ObjC special blocks.
+      if (TheLine->First->is(tok::l_brace) && PreviousLine.First->is(tok::at) &&
+          PreviousLine.First->Next) {
+        tok::ObjCKeywordKind kwId =
+            PreviousLine.First->Next->Tok.getObjCKeywordID();
+        if (kwId == clang::tok::objc_autoreleasepool ||
+            kwId == clang::tok::objc_synchronized)
+          return 0;
+      }
+      // Don't merge block with left brace wrapped after case labels.
+      if (TheLine->First->is(tok::l_brace) &&
+          PreviousLine.First->isOneOf(tok::kw_case, tok::kw_default))
         return 0;
-    }
-    // Don't merge block with left brace wrapped after case labels
-    if (TheLine->First->is(tok::l_brace) && I != AnnotatedLines.begin() &&
-        I[-1]->First->isOneOf(tok::kw_case, tok::kw_default))
-      return 0;
 
-    // Don't merge an empty template class or struct if SplitEmptyRecords
-    // is defined.
-    if (Style.BraceWrapping.SplitEmptyRecord &&
-        TheLine->Last->is(tok::l_brace) && I != AnnotatedLines.begin() &&
-        I[-1]->Last) {
-      const FormatToken *Previous = I[-1]->Last;
-      if (Previous) {
-        if (Previous->is(tok::comment))
-          Previous = Previous->getPreviousNonComment();
+      // Don't merge an empty template class or struct if SplitEmptyRecords
+      // is defined.
+      if (Style.BraceWrapping.SplitEmptyRecord &&
+          TheLine->Last->is(tok::l_brace) && PreviousLine.Last) {
+        const FormatToken *Previous = PreviousLine.Last;
         if (Previous) {
-          if (Previous->is(tok::greater) && !I[-1]->InPPDirective)
-            return 0;
-          if (Previous->is(tok::identifier)) {
-            const FormatToken *PreviousPrevious =
-                Previous->getPreviousNonComment();
-            if (PreviousPrevious &&
-                PreviousPrevious->isOneOf(tok::kw_class, tok::kw_struct))
+          if (Previous->is(tok::comment))
+            Previous = Previous->getPreviousNonComment();
+          if (Previous) {
+            if (Previous->is(tok::greater) && !PreviousLine.InPPDirective)
               return 0;
+            if (Previous->is(tok::identifier)) {
+              const FormatToken *PreviousPrevious =
+                  Previous->getPreviousNonComment();
+              if (PreviousPrevious &&
+                  PreviousPrevious->isOneOf(tok::kw_class, tok::kw_struct))
+                return 0;
+            }
           }
         }
       }
     }
 
-    // Try to merge a block with left brace unwrapped that wasn't yet covered
+    // Try to merge a block with left brace unwrapped that wasn't yet covered.
     if (TheLine->Last->is(tok::l_brace)) {
       const FormatToken *Tok = TheLine->First;
       bool ShouldMerge = false;
@@ -401,21 +406,21 @@
       }
       if (Tok->isOneOf(tok::kw_class, tok::kw_struct)) {
         ShouldMerge = !Style.BraceWrapping.AfterClass ||
-                      (I[1]->First->is(tok::r_brace) &&
+                      (NextLine.First->is(tok::r_brace) &&
                        !Style.BraceWrapping.SplitEmptyRecord);
       } else if (Tok->is(tok::kw_enum)) {
         ShouldMerge = Style.AllowShortEnumsOnASingleLine;
       } else {
         ShouldMerge = !Style.BraceWrapping.AfterFunction ||
-                      (I[1]->First->is(tok::r_brace) &&
+                      (NextLine.First->is(tok::r_brace) &&
                        !Style.BraceWrapping.SplitEmptyFunction);
       }
       return ShouldMerge ? tryMergeSimpleBlock(I, E, Limit) : 0;
     }
-    // Try to merge a function block with left brace wrapped
-    if (I[1]->First->is(TT_FunctionLBrace) &&
+    // Try to merge a function block with left brace wrapped.
+    if (NextLine.First->is(TT_FunctionLBrace) &&
         Style.BraceWrapping.AfterFunction) {
-      if (I[1]->Last->is(TT_LineComment))
+      if (NextLine.Last->is(TT_LineComment))
         return 0;
 
       // Check for Limit <= 2 to account for the " {".
@@ -426,7 +431,7 @@
       unsigned MergedLines = 0;
       if (MergeShortFunctions ||
           (Style.AllowShortFunctionsOnASingleLine >= FormatStyle::SFS_Empty &&
-           I[1]->First == I[1]->Last && I + 2 != E &&
+           NextLine.First == NextLine.Last && I + 2 != E &&
            I[2]->First->is(tok::r_brace))) {
         MergedLines = tryMergeSimpleBlock(I + 1, E, Limit);
         // If we managed to merge the block, count the function header, which is