The change adds the following: - support of lzcnt and tzcnt instructions, - unit tests for lzcnt/tzcnt, - ability to emit bsf/bsr in case lzcnt/tzcnt were turned off from the command line, - tightening the stamps produced by ScanBitForward/ReverseNode nodes. Webrev: http://cr.openjdk.java.net/~iveresov/lztzcnt/webrev.00/ Thanks! igor