Jim Mulder wrote:
That's why LMD has the following Programming Note:
3. The combination of a LOAD MULTIPLE instruction
and a LOAD MULTIPLE HIGH instruction
provides equal or better performance than a
LOAD MULTIPLE DISJOINT instruction for the
same register range. LOAD MULTIPLE DIS-
JOINT is for use when the second or fourth operand
must be addressed by means of one of the
registers loaded.
Yeah. Once you restore the high-halves in 64-bit mode using LMH, you're
potentially unable to issue the LM to restore the low halves--and vice
versa. We had to do some slightly "tricky" stuff to do what we needed to
do without LMD. It was well worth it.
--
Edward E Jaffe
Phoenix Software International, Inc
5200 W Century Blvd, Suite 800
Los Angeles, CA 90045
310-338-0400 x318
[email protected]
http://www.phoenixsoftware.com/
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