On Sun, 1 Aug 2010 08:03:19 -0400, Don Higgins wrote: >the 4 instruction loop solution I coded uses the same >reference table you described but avoids the TROO and scratch storage >requirement by doing IC of string byte and then another IC from table >followed by AR and BXLE.
This method is trivial to speed up at the expense of the table size. Instead of using IC for each byte, use LLH (or ICM with a mask of 3) to handle two bytes at a time with a table size of 65536 bytes - then a final IC if there is an odd number of bytes. The same can be done for 3 to 8 bytes at a time but the table quickly becomes impractical. (8 bytes at a time requires a data space for the table, an operating system that supports 2^64 byte data spaces, and enough real storage to avoid paging it.) BTW, APAR PK97799 is now closed and the description has been updated with the new instruction mnemonics.
