Re: Parsing timestamps?

anton@mips.complang.tuwien.ac.at (Anton Ertl) writes:

But I decided to use a recursive approach (recursive-sum, REC) that
uses the largest 2^k<n as the left child and the rest as the right
child, and as base cases for the recursion use a straight-line
balanced-tree evaluation for 2^k with k<=7 (and combine these for n
that are not 2^k).  For systems with tiny FP stacks, I added the
option to save intermediate results on a software stack in the
recursive word.  Concerning the straight-line code, it turned out that
the highest k I could use on sf64 and vfx64 is 5 (corresponding to 6
FP stack items); it's not clear to me why; on lxf I can use k=7 (and
it uses the 387 stack, too).

Actually, after writing that, I found out the reasons for the FP stack
overflows, and in the published versions and the results I use k=7 on
all systems.  It's really easy to leave an FP stack item on the FP
stack while calling another word, and that's not so good if you do it
while calling sum128:-).

- anton
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