• Martin Bidlingmaier's avatar
    [regexp] Support more quantifiers in experimental engine · f2a832ca
    Martin Bidlingmaier authored
    Previously to this commit only quantifiers of the form /<x>*/, i.e.
    arbitrarily often greedy repetition, were implemented.  Now a much
    larger class is supported, e.g. + and ? and their non-greedy variants.
    Because it came up repeatedly during the implementation, the commit also
    adds the Label and DeferredLabel classes to patch JMP and FORK target
    addresses more easily.
    
    Still not supported are the following quantifiers:
    - Possessive quantifiers, where I'm not entirely sure whether they could
      be implemented in principle. Re2 doesn't support them.
    - Quantifiers with large but finite numbers for min and max numbers of
      repetitions, as in e.g. /<x>{9000, 90000}/. These are currently
      limited to some small value. This is because the body of such
      repetitions is unrolled explicitly, so the size of the bytecode is
      linear in the number of repetitions.
    
    Cq-Include-Trybots: luci.v8.try:v8_linux64_fyi_rel_ng
    Bug: v8:10765
    Change-Id: Id04d893252588abb0f80c3cb33cfc707f6601ea0
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2387575
    Commit-Queue: Jakob Gruber <jgruber@chromium.org>
    Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#69759}
    f2a832ca
regexp-ast.h 21.4 KB