shave some cycles (use X as cache for last dst address)

2024-11-23 12:33:32 +00:00 · 2020-11-21 17:17:19 -05:00 · 2020-11-21 17:17:19 -05:00 · 9a1cceb49e
commit 9a1cceb49e
parent 2d0dbe2b75
1 changed files with 7 additions and 5 deletions
--- a/src/fx/fx.dhgr.soft.diagonal.a
+++ b/src/fx/fx.dhgr.soft.diagonal.a
@ -5,7 +5,7 @@
 !to "build/FX/DHGR.SOFT.DIAG",plain
 *=$6000

-lastdsthi = $C8
+row = $C8
 src = $C9
 dst = $CB
 y = $CD
@ -27,7 +27,7 @@ zphgrrowhi = $E8
 }

 !macro RESET_HGR_HI {
-         lda   lastdsthi
+         txa
         sta   dst+1
         eor   #$60
         sta   src+1
@ -73,16 +73,18 @@ zphgrrowhi = $E8
         lda   #39
         sta   col
 ColLoop
-         ldx   #23
+         lda   #23
+         sta   row
         ldy   col
         sty   y
 RowLoop
+         ldx   row
         lda   zphgrrowlo, x
         sta   src
         sta   dst
         lda   zphgrrowhi, x
         sta   dst+1
-         sta   lastdsthi
+         tax
         eor   #$60
         sta   src+1

@ -268,7 +270,7 @@ RowLoop
         sta   $C002
         sta   $C004
         inc   y
-         dex
+         dec   row
         +LBPL RowLoop
         lda   $c000
         bmi   @exit