Hi Segher,
On 28/07/15 19:04, Segher Boessenkool wrote:
> On Tue, Jul 28, 2015 at 12:19:54PM +0200, Thomas Huth wrote:
>> : invert-region ( addr len -- )
>> - 0 ?DO dup dup rb@ -1 xor swap rb! 1+ LOOP drop
>> -;
>> -
>> -: invert-region-x ( addr len -- )
>> - /x / 0 ?DO dup dup rx@ -1 xor s
On Tue, Jul 28, 2015 at 12:19:54PM +0200, Thomas Huth wrote:
> : invert-region ( addr len -- )
> - 0 ?DO dup dup rb@ -1 xor swap rb! 1+ LOOP drop
> -;
> -
> -: invert-region-x ( addr len -- )
> - /x / 0 ?DO dup dup rx@ -1 xor swap rx! xa1+ LOOP drop
> + 2dup or 7 and CASE
> + 0 OF 3 rsh
The introduction of invert-region already speeded up the cursor
drawing very much. But there is still space for improvement:
So far invert-region is accessing the memory only byte by byte,
but with some additional logic that checks the alignment of the
address and the length of the area, we can als
