Changed RegExp parser to use a recursive data structure instead of stack-based recursion.

Shouldn't run out of stack space while parsing deeply nested regexps.
Might be a little faster.

Review URL: http://codereview.chromium.org/149069


git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2345 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ast.h

@@ -1575,16 +1575,10 @@ class RegExpQuantifier: public RegExpTree {
 };
 
 
-enum CaptureAvailability {
-  CAPTURE_AVAILABLE,
-  CAPTURE_UNREACHABLE,
-  CAPTURE_PERMANENTLY_UNREACHABLE
-};
-
 class RegExpCapture: public RegExpTree {
  public:
   explicit RegExpCapture(RegExpTree* body, int index)
-      : body_(body), index_(index), available_(CAPTURE_AVAILABLE) { }
+      : body_(body), index_(index) { }
   virtual void* Accept(RegExpVisitor* visitor, void* data);
   virtual RegExpNode* ToNode(RegExpCompiler* compiler,
                              RegExpNode* on_success);
@@ -1600,16 +1594,11 @@ class RegExpCapture: public RegExpTree {
   virtual int max_match() { return body_->max_match(); }
   RegExpTree* body() { return body_; }
   int index() { return index_; }
-  inline CaptureAvailability available() { return available_; }
-  inline void set_available(CaptureAvailability availability) {
-    available_ = availability;
-  }
   static int StartRegister(int index) { return index * 2; }
   static int EndRegister(int index) { return index * 2 + 1; }
  private:
   RegExpTree* body_;
   int index_;
-  CaptureAvailability available_;
 };
 
 

test/cctest/test-regexp.cc

@@ -204,8 +204,8 @@ TEST(Parser) {
   CHECK_PARSE_EQ("(?=a){9,10}a", "(: (-> + 'a') 'a')");
   CHECK_PARSE_EQ("(?!a)?a", "'a'");
   CHECK_PARSE_EQ("\\1(a)", "(^ 'a')");
-  CHECK_PARSE_EQ("(?!(a))\\1", "(-> - (^ 'a'))");
-  CHECK_PARSE_EQ("(?!\\1(a\\1)\\1)\\1", "(-> - (: (^ 'a') (<- 1)))");
+  CHECK_PARSE_EQ("(?!(a))\\1", "(: (-> - (^ 'a')) (<- 1))");
+  CHECK_PARSE_EQ("(?!\\1(a\\1)\\1)\\1", "(: (-> - (: (^ 'a') (<- 1))) (<- 1))");
   CHECK_PARSE_EQ("[\\0]", "[\\x00]");
   CHECK_PARSE_EQ("[\\11]", "[\\x09]");
   CHECK_PARSE_EQ("[\\11a]", "[\\x09 a]");