05-29-2010, 12:53 AM
Okay, I've reverse engineered the hisoft CM you put above (see attached file).
The routine is fair, and it's doing even an array initialization on *each pass* :!: :o
The bad news first: it's effectively working on a vector. Doing this might break the ZX BASIC compiler, since it's supposed to be multi-architectural.
The good news: Most of the time is gone in the 16bit multiplication used for array accesses. Since most of the arrays and element sizes are near 0, this routine uses it's own array-multiplication (HISoft Basic is doing the same for some multiplications). This will reduce the execution time down to 1.11 segs.
Even better, using multidimensional arrays does only add a little overhead (about 1.39 for 2 dims).
The FOR...NEXT does the comparison at the reverse. This is 10 T-states faster, so I change the FOR...NEXT scheme that way to.
Now this REALLY needs intensive testing (array and FOR...NEXT loops). I'm uploading a new 1.2.6 beta-r1571, if someone is interested.
The routine is fair, and it's doing even an array initialization on *each pass* :!: :o
The bad news first: it's effectively working on a vector. Doing this might break the ZX BASIC compiler, since it's supposed to be multi-architectural.
The good news: Most of the time is gone in the 16bit multiplication used for array accesses. Since most of the arrays and element sizes are near 0, this routine uses it's own array-multiplication (HISoft Basic is doing the same for some multiplications). This will reduce the execution time down to 1.11 segs.
Even better, using multidimensional arrays does only add a little overhead (about 1.39 for 2 dims).
The FOR...NEXT does the comparison at the reverse. This is 10 T-states faster, so I change the FOR...NEXT scheme that way to.
Now this REALLY needs intensive testing (array and FOR...NEXT loops). I'm uploading a new 1.2.6 beta-r1571, if someone is interested.