Allows backtracking to clear registers instead of pushing and popping
them to restore state.
Redo of 1135 with bug fixed.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1156 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Reduces number of pushes when flushing a trace. Some are converted to clears
in the undo-code instead, and some just ignored if they have no value worth restoring.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1136 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
the alternatives in a choice node. The quick checks
are conservative in the sense that they only detect
failure with certainty. Checks can do 2 or 4 characters
at a time.
* Inline the quick checks to allow the alternatives to
be checked without branching in the common case where
they fail.
Review URL: http://codereview.chromium.org/14194
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1005 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
* Facility for generating a node several ways. This allows
code to be generated for a node knowing where it is trying
to match relative to the 'current position' and it allows
code to be generated that knows where to backtrack to. Both
allow dramatic reductions in the amount of popping and pushing
on the stack and the number of indirect jumps.
* Generate special backtracking for greedy quantifiers on
constant-length atoms. This allows .* to run in constant
space relative to input string size.
* When we are checking a long sequence of characters or character
classes in the input then we do them right to left and only the
first (rightmost) needs to check for end-of-string.
* Record the pattern in the profile instead of just <CompiledRegExp>
* Nodes no longer contain an on_failure_ node. This was only used
for lookaheads and they are now handled with a choice node instead.
Review URL: http://codereview.chromium.org/12900
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@930 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
