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reduse a STA instruction in circle code

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hugova 2025-07-16 20:18:53 +02:00
parent 38070296d0
commit 49a330d24c
3 changed files with 85 additions and 86 deletions
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19
wip-hugo/routines/circle/circle.inc
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@ -5,16 +5,15 @@
;; and others from pixel.inc ;; and others from pixel.inc
;; private args ;; private args
t1 = $E0 t1 = $E0
t2 = $E1
X_math = radius X_math = radius
Y_math = $E2 Y_math = $E1
byte_to_paint_qaa = $E3 byte_to_paint_qaa = $E2
byte_to_paint_qcb = $E4 byte_to_paint_qcb = $E3
byte_to_paint_qca = $E5 byte_to_paint_qca = $E4
byte_to_paint_qdb = $E6 byte_to_paint_qdb = $E5
btp_mem_pos_qaa = btp_mem_pos btp_mem_pos_qaa = btp_mem_pos
btp_mem_pos_qcb = $E7 ; 16bit value (uses E8) btp_mem_pos_qcb = $E6 ; 16bit value (uses E7)
; E9 - EA is used by pixel.inc ; E9 - EA is used by pixel.inc
btp_mem_pos_qdb = $EB ; 16bit value (uses EC) btp_mem_pos_qdb = $EB ; 16bit value (uses EC)
btp_mem_pos_qda = $ED ; 16bit value (uses EE) btp_mem_pos_qda = $ED ; 16bit value (uses EE)
@ -24,9 +23,9 @@
btp_mem_pos_qbb = $D6 ; 16bit value (uses D7) btp_mem_pos_qbb = $D6 ; 16bit value (uses D7)
Y_qda = $EF Y_qda = $EF
Y_qdb = $D8 Y_qdb = $E8
Y_qbb = $D9 Y_qbb = $D8
Y_qaa = $DA Y_qaa = $D9
;;Reuse addresses, be carful here! ;;Reuse addresses, be carful here!
temp__ = Y_qaa temp__ = Y_qaa
temp_ = Y_qda temp_ = Y_qda

2
wip-hugo/routines/circle/circle.s
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@ -229,7 +229,7 @@ qcb_x_end:
;; t2 = t1 - x ;; t2 = t1 - x
SEC SEC
SBC X_math SBC X_math
STA t2 ;t2 do not need to be saved :)
;; if t2 < 0 then skip to endif ;; if t2 < 0 then skip to endif
;; we can skipp CMP #$00 because SBC above do the same ;; we can skipp CMP #$00 because SBC above do the same
BPL if BPL if

0
wip-hugo/routines/memory/memset_alt.s Executable file → Normal file
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