Use finite-length end-anchored regexps to reduce part of regexp that is searched.

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index e8d54e46898de2bcb27a5b842b8916829aaf17bf..a01e48daeb3a77a56e94272ded74e11a887e009b 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -1523,7 +1523,8 @@ class RegExpTree: public ZoneObject {
   virtual RegExpNode* ToNode(RegExpCompiler* compiler,
                              RegExpNode* on_success) = 0;
   virtual bool IsTextElement() { return false; }
-  virtual bool IsAnchored() { return false; }
+  virtual bool IsAnchoredAtStart() { return false; }
+  virtual bool IsAnchoredAtEnd() { return false; }
   virtual int min_match() = 0;
   virtual int max_match() = 0;
   // Returns the interval of registers used for captures within this
@@ -1548,7 +1549,8 @@ class RegExpDisjunction: public RegExpTree {
   virtual RegExpDisjunction* AsDisjunction();
   virtual Interval CaptureRegisters();
   virtual bool IsDisjunction();
-  virtual bool IsAnchored();
+  virtual bool IsAnchoredAtStart();
+  virtual bool IsAnchoredAtEnd();
   virtual int min_match() { return min_match_; }
   virtual int max_match() { return max_match_; }
   ZoneList<RegExpTree*>* alternatives() { return alternatives_; }
@@ -1568,7 +1570,8 @@ class RegExpAlternative: public RegExpTree {
   virtual RegExpAlternative* AsAlternative();
   virtual Interval CaptureRegisters();
   virtual bool IsAlternative();
-  virtual bool IsAnchored();
+  virtual bool IsAnchoredAtStart();
+  virtual bool IsAnchoredAtEnd();
   virtual int min_match() { return min_match_; }
   virtual int max_match() { return max_match_; }
   ZoneList<RegExpTree*>* nodes() { return nodes_; }
@@ -1595,7 +1598,8 @@ class RegExpAssertion: public RegExpTree {
                              RegExpNode* on_success);
   virtual RegExpAssertion* AsAssertion();
   virtual bool IsAssertion();
-  virtual bool IsAnchored();
+  virtual bool IsAnchoredAtStart();
+  virtual bool IsAnchoredAtEnd();
   virtual int min_match() { return 0; }
   virtual int max_match() { return 0; }
   Type type() { return type_; }
@@ -1768,7 +1772,8 @@ class RegExpCapture: public RegExpTree {
                             RegExpCompiler* compiler,
                             RegExpNode* on_success);
   virtual RegExpCapture* AsCapture();
-  virtual bool IsAnchored();
+  virtual bool IsAnchoredAtStart();
+  virtual bool IsAnchoredAtEnd();
   virtual Interval CaptureRegisters();
   virtual bool IsCapture();
   virtual int min_match() { return body_->min_match(); }
@@ -1800,7 +1805,7 @@ class RegExpLookahead: public RegExpTree {
   virtual RegExpLookahead* AsLookahead();
   virtual Interval CaptureRegisters();
   virtual bool IsLookahead();
-  virtual bool IsAnchored();
+  virtual bool IsAnchoredAtStart();
   virtual int min_match() { return 0; }
   virtual int max_match() { return 0; }
   RegExpTree* body() { return body_; }