Change the datastructure for UnwrappedLines.

It was quite convoluted leading to us accidentally introducing O(N^2)
complexity while copying from UnwrappedLine to AnnotatedLine. We might
still want to improve the datastructure in AnnotatedLine (most
importantly not put them in a vector where they need to be copied on
vector resizing but that will be done as a follow-up.

This fixes most of the regression in llvm.org/PR14959.

No formatting changes intended.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172602 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 939038e2a5f44d57a471f44ddc1a51279ef353c3..dbed75c3f19fd3032396ae9f48c3904631af69aa 100644 (file)
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -92,9 +92,30 @@ public:
 
 class AnnotatedLine {
 public:
-  AnnotatedLine(const FormatToken &FormatTok, unsigned Level,
-                bool InPPDirective)
-      : First(FormatTok), Level(Level), InPPDirective(InPPDirective) {}
+  AnnotatedLine(const UnwrappedLine &Line)
+      : First(Line.Tokens.front()), Level(Line.Level),
+        InPPDirective(Line.InPPDirective) {
+    assert(!Line.Tokens.empty());
+    AnnotatedToken *Current = &First;
+    for (std::list<FormatToken>::const_iterator I = ++Line.Tokens.begin(),
+                                                E = Line.Tokens.end();
+         I != E; ++I) {
+      Current->Children.push_back(*I);
+      Current->Children[0].Parent = Current;
+      Current = &Current->Children[0];
+    }
+    Last = Current;
+  }
+  AnnotatedLine(const AnnotatedLine &Other)
+      : First(Other.First), Type(Other.Type), Level(Other.Level),
+        InPPDirective(Other.InPPDirective) {
+    Last = &First;
+    while (!Last->Children.empty()) {
+      Last->Children[0].Parent = Last;
+      Last = &Last->Children[0];
+    }
+  }
+
   AnnotatedToken First;
   AnnotatedToken *Last;
 
@@ -945,16 +966,6 @@ public:
     bool ColonIsObjCMethodExpr;
   };
 
-  void createAnnotatedTokens(AnnotatedToken &Current) {
-    if (Current.FormatTok.Children.empty()) {
-      Line.Last = &Current;
-    } else {
-      Current.Children.push_back(AnnotatedToken(Current.FormatTok.Children[0]));
-      Current.Children.back().Parent = &Current;
-      createAnnotatedTokens(Current.Children.back());
-    }
-  }
-
   void calculateExtraInformation(AnnotatedToken &Current) {
     Current.SpaceRequiredBefore = spaceRequiredBefore(Current);
 
@@ -978,9 +989,6 @@ public:
   }
 
   void annotate() {
-    Line.Last = &Line.First;
-    createAnnotatedTokens(Line.First);
-
     AnnotatingParser Parser(Line.First);
     Line.Type = Parser.parseLine();
     if (Line.Type == LT_Invalid)
@@ -1619,8 +1627,7 @@ private:
   }
 
   virtual void consumeUnwrappedLine(const UnwrappedLine &TheLine) {
-    AnnotatedLines.push_back(
-        AnnotatedLine(TheLine.RootToken, TheLine.Level, TheLine.InPPDirective));
+    AnnotatedLines.push_back(AnnotatedLine(TheLine));
   }
 
   /// \brief Add a new line and the required indent before the first Token

diff --git a/lib/Format/UnwrappedLineParser.cpp b/lib/Format/UnwrappedLineParser.cpp
index fe522ac9d8f8d8f41754c8a3980f6f1fbdc3ab5b..9a29ff011ae17ff76c99c36a6a06d5b4e5254845 100644 (file)
--- a/lib/Format/UnwrappedLineParser.cpp
+++ b/lib/Format/UnwrappedLineParser.cpp
@@ -81,25 +81,17 @@ class ScopedLineState {
 public:
   ScopedLineState(UnwrappedLineParser &Parser) : Parser(Parser) {
     PreBlockLine = Parser.Line.take();
-    Parser.Line.reset(new UnwrappedLine(*PreBlockLine));
-    assert(Parser.LastInCurrentLine == NULL ||
-           Parser.LastInCurrentLine->Children.empty());
-    PreBlockLastToken = Parser.LastInCurrentLine;
-    PreBlockRootTokenInitialized = Parser.RootTokenInitialized;
-    Parser.RootTokenInitialized = false;
-    Parser.LastInCurrentLine = NULL;
+    Parser.Line.reset(new UnwrappedLine());
+    Parser.Line->Level = PreBlockLine->Level;
+    Parser.Line->InPPDirective = PreBlockLine->InPPDirective;
   }
 
   ~ScopedLineState() {
-    if (Parser.RootTokenInitialized) {
+    if (!Parser.Line->Tokens.empty()) {
       Parser.addUnwrappedLine();
     }
-    assert(!Parser.RootTokenInitialized);
+    assert(Parser.Line->Tokens.empty());
     Parser.Line.reset(PreBlockLine);
-    Parser.RootTokenInitialized = PreBlockRootTokenInitialized;
-    Parser.LastInCurrentLine = PreBlockLastToken;
-    assert(Parser.LastInCurrentLine == NULL ||
-           Parser.LastInCurrentLine->Children.empty());
     Parser.MustBreakBeforeNextToken = true;
   }
 
@@ -107,15 +99,12 @@ private:
   UnwrappedLineParser &Parser;
 
   UnwrappedLine *PreBlockLine;
-  FormatToken* PreBlockLastToken;
-  bool PreBlockRootTokenInitialized;
 };
 
 UnwrappedLineParser::UnwrappedLineParser(
     clang::DiagnosticsEngine &Diag, const FormatStyle &Style,
     FormatTokenSource &Tokens, UnwrappedLineConsumer &Callback)
-    : Line(new UnwrappedLine), RootTokenInitialized(false),
-      LastInCurrentLine(NULL), MustBreakBeforeNextToken(false), Diag(Diag),
+    : Line(new UnwrappedLine), MustBreakBeforeNextToken(false), Diag(Diag),
       Style(Style), Tokens(&Tokens), Callback(Callback) {
 }
 
@@ -659,7 +648,7 @@ void UnwrappedLineParser::parseObjCProtocol() {
 }
 
 void UnwrappedLineParser::addUnwrappedLine() {
-  if (!RootTokenInitialized)
+  if (Line->Tokens.empty())
     return;
   // Consume trailing comments.
   while (!eof() && FormatTok.NewlinesBefore == 0 &&
@@ -667,17 +656,17 @@ void UnwrappedLineParser::addUnwrappedLine() {
     nextToken();
   }
 #ifdef UNWRAPPED_LINE_PARSER_DEBUG_OUTPUT
-  FormatToken* NextToken = &Line->RootToken;
   llvm::errs() << "Line: ";
-  while (NextToken) {
-    llvm::errs() << NextToken->Tok.getName() << " ";
-    NextToken = NextToken->Children.empty() ? NULL : &NextToken->Children[0];
+  for (std::list<FormatToken>::iterator I = Line->Tokens.begin(),
+                                        E = Line->Tokens.end();
+       I != E; ++I) {
+    llvm::errs() << I->Tok.getName() << " ";
+
   }
   llvm::errs() << "\n";
 #endif
   Callback.consumeUnwrappedLine(*Line);
-  RootTokenInitialized = false;
-  LastInCurrentLine = NULL;
+  Line->Tokens.clear();
 }
 
 bool UnwrappedLineParser::eof() const {
@@ -687,17 +676,9 @@ bool UnwrappedLineParser::eof() const {
 void UnwrappedLineParser::nextToken() {
   if (eof())
     return;
-  if (RootTokenInitialized) {
-    assert(LastInCurrentLine->Children.empty());
-    LastInCurrentLine->Children.push_back(FormatTok);
-    LastInCurrentLine = &LastInCurrentLine->Children.back();
-  } else {
-    Line->RootToken = FormatTok;
-    RootTokenInitialized = true;
-    LastInCurrentLine = &Line->RootToken;
-  }
+  Line->Tokens.push_back(FormatTok);
   if (MustBreakBeforeNextToken) {
-    LastInCurrentLine->MustBreakBefore = true;
+    Line->Tokens.back().MustBreakBefore = true;
     MustBreakBeforeNextToken = false;
   }
   readToken();

diff --git a/lib/Format/UnwrappedLineParser.h b/lib/Format/UnwrappedLineParser.h
index 08faff15af1d77e7c62848eeb2115b1d267d4ba1..21a973d9dd3bd185f7ebf91e76a03fbff6f80bc5 100644 (file)
--- a/lib/Format/UnwrappedLineParser.h
+++ b/lib/Format/UnwrappedLineParser.h
@@ -24,7 +24,7 @@
 #include "clang/Format/Format.h"
 #include "clang/Lex/Lexer.h"
 
-#include <vector>
+#include <list>
 
 namespace clang {
 
@@ -76,11 +76,6 @@ struct FormatToken {
   /// This happens for example when a preprocessor directive ended directly
   /// before the token.
   bool MustBreakBefore;
-
-  // FIXME: We currently assume that there is exactly one token in this vector
-  // except for the very last token that does not have any children.
-  /// \brief All tokens that logically follow this token.
-  std::vector<FormatToken> Children;
 };
 
 /// \brief An unwrapped line is a sequence of \c Token, that we would like to
@@ -93,8 +88,8 @@ struct UnwrappedLine {
   UnwrappedLine() : Level(0), InPPDirective(false) {
   }
 
-  /// \brief The \c Token comprising this \c UnwrappedLine.
-  FormatToken RootToken;
+  /// \brief The \c Tokens comprising this \c UnwrappedLine.
+  std::list<FormatToken> Tokens;
 
   /// \brief The indent level of the \c UnwrappedLine.
   unsigned Level;
@@ -160,8 +155,6 @@ private:
   // subtracted from beyond 0. Introduce a method to subtract from Line.Level
   // and use that everywhere in the Parser.
   OwningPtr<UnwrappedLine> Line;
-  bool RootTokenInitialized;
-  FormatToken *LastInCurrentLine;
   FormatToken FormatTok;
   bool MustBreakBeforeNextToken;