[PATCH] Quick look-up for block in loop

[Wan, Xiaofei]

  Hal:

  Thanks for your comments, I don't think the DenseSet could be cached since the blocks in loop may be changed.

  Finally, when you post patches to llvm-reviews, please generate them with -U999999 so that we can see the full context in the web interface.
  ~~~~What diff tool do you usually use, it seems svn diff has no option -U999999, thanks.


  Thanks
  Wan Xiaofei

http://llvm-reviews.chandlerc.com/D2014