From 07c2451abd28dd2598f0570622b4324288cbaccc Mon Sep 17 00:00:00 2001
From: Roberto Raggi <roberto.raggi@nokia.com>
Date: Fri, 23 Oct 2009 11:21:36 +0200
Subject: [PATCH] Use memoization to reduce the backtracking when parsing
template arguments.
---
src/shared/cplusplus/Parser.cpp | 25 +++++++++++++++++++++++--
src/shared/cplusplus/Parser.h | 14 +++++++++++++-
2 files changed, 36 insertions(+), 3 deletions(-)
diff --git a/src/shared/cplusplus/Parser.cpp b/src/shared/cplusplus/Parser.cpp
index 24851c991da..67e260230c0 100644
--- a/src/shared/cplusplus/Parser.cpp
+++ b/src/shared/cplusplus/Parser.cpp
@@ -328,8 +328,6 @@ bool Parser::parseTemplateId(NameAST *&node)
DEBUG_THIS_RULE();
const unsigned start = cursor();
- Rewind rewind(this);
- rewind.mark();
if (LA() == T_IDENTIFIER && LA(2) == T_LESS) {
TemplateIdAST *ast = new (_pool) TemplateIdAST;
@@ -692,8 +690,26 @@ bool Parser::parseOperatorFunctionId(NameAST *&node)
return true;
}
+Parser::TemplateArgumentListEntry *Parser::templateArgumentListEntry(unsigned tokenIndex)
+{
+ for (unsigned i = 0; i < _templateArgumentList.size(); ++i) {
+ TemplateArgumentListEntry *entry = &_templateArgumentList[i];
+ if (entry->index == tokenIndex)
+ return entry;
+ }
+
+ return 0;
+}
+
bool Parser::parseTemplateArgumentList(TemplateArgumentListAST *&node)
{
+ if (TemplateArgumentListEntry *entry = templateArgumentListEntry(cursor())) {
+ rewind(entry->cursor);
+ return entry->ast;
+ }
+
+ unsigned start = cursor();
+
DEBUG_THIS_RULE();
TemplateArgumentListAST **template_argument_ptr = &node;
ExpressionAST *template_argument = 0;
@@ -711,8 +727,13 @@ bool Parser::parseTemplateArgumentList(TemplateArgumentListAST *&node)
template_argument_ptr = &(*template_argument_ptr)->next;
}
}
+
+ _templateArgumentList.push_back(TemplateArgumentListEntry(start, cursor(), node));
return true;
}
+
+ _templateArgumentList.push_back(TemplateArgumentListEntry(start, cursor(), 0));
+
return false;
}
diff --git a/src/shared/cplusplus/Parser.h b/src/shared/cplusplus/Parser.h
index 2a7c15dfa3e..d9ccf6ab490 100644
--- a/src/shared/cplusplus/Parser.h
+++ b/src/shared/cplusplus/Parser.h
@@ -54,7 +54,6 @@
#include "Token.h"
#include "TranslationUnit.h"
-
namespace CPlusPlus {
class CPLUSPLUS_EXPORT Parser
@@ -287,6 +286,17 @@ private:
inline void rewind(unsigned cursor)
{ _tokenIndex = cursor; }
+ struct TemplateArgumentListEntry {
+ unsigned index;
+ unsigned cursor;
+ TemplateArgumentListAST *ast;
+
+ TemplateArgumentListEntry(unsigned index = 0, unsigned cursor = 0, TemplateArgumentListAST *ast = 0)
+ : index(index), cursor(cursor), ast(ast) {}
+ };
+
+ TemplateArgumentListEntry *templateArgumentListEntry(unsigned tokenIndex);
+
private:
TranslationUnit *_translationUnit;
Control *_control;
@@ -298,6 +308,8 @@ private:
bool _inFunctionBody: 1;
bool _inObjCImplementationContext: 1;
+ Array<TemplateArgumentListEntry> _templateArgumentList;
+
class Rewind;
friend class Rewind;
--
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