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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
View file

@ -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

150
wip-hugo/routines/memory/memset_alt.s Executable file → Normal file
View file

@ -1,75 +1,75 @@
;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*- ;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*-
;; Sets memory in 'A'-registry to all addresses from 'A_start' until 'A_start' + 'length' ;; Sets memory in 'A'-registry to all addresses from 'A_start' until 'A_start' + 'length'
;; Modifies A, X and A_start ;; Modifies A, X and A_start
.proc memset .proc memset
.include "mem.inc" .include "mem.inc"
;; big_set sets the memory in $ff chunks. ;; big_set sets the memory in $ff chunks.
;; skipp if length >= $ff ;; skipp if length >= $ff
LDX length +1 LDX length +1
BNE big_set BNE big_set
JMP small_set JMP small_set
big_set: ;sets $ff of memory big_set: ;sets $ff of memory
;; Y value do not matter, will go through all anyway! ;; Y value do not matter, will go through all anyway!
.repeat $ff .repeat $ff
STA (A_start), Y STA (A_start), Y
DEY DEY
.endrepeat .endrepeat
STA (A_start), Y ; dont forget Y =0 STA (A_start), Y ; dont forget Y =0
big_set_end: big_set_end:
;;set all hole $ff memory chunks! ;;set all hole $ff memory chunks!
INC A_start + 1 INC A_start + 1
DEX ;; length +1 -- DEX ;; length +1 --
BEQ small_set BEQ small_set
JMP big_set JMP big_set
small_set: small_set:
STA data_to_write STA data_to_write
LDA length LDA length
STA length_copy STA length_copy
;; calculate rts-position ;; calculate rts-position
LDX #$00 LDX #$00
STX length + 1 STX length + 1
;; 3 bytes = STA DEY NOP = seting 1 byte of memory. ;; 3 bytes = STA DEY NOP = seting 1 byte of memory.
;; So we need to calculate: length*3 ;; So we need to calculate: length*3
Mult_16 length, length + 1 Mult_16 length, length + 1
; A= length_copy ; A= length_copy
ADC length ADC length
TAY TAY
LDA length + 1 LDA length + 1
ADC #$00 ADC #$00
STA length + 1 STA length + 1
;; Now RTS_pointer + Y = length*3 + big_set_label ;; Now RTS_pointer + Y = length*3 + big_set_label
LDA #<big_set LDA #<big_set
STA RTS_pointer STA RTS_pointer
LDA #>big_set LDA #>big_set
ADC length + 1 ADC length + 1
STA RTS_pointer + 1 STA RTS_pointer + 1
;; read data we will change to RTS ;; read data we will change to RTS
STY Y_copy STY Y_copy
LDA (RTS_pointer), Y LDA (RTS_pointer), Y
TAX TAX
;; set RTS in big_set ;; set RTS in big_set
LDA #$60 LDA #$60
STA (RTS_pointer), Y STA (RTS_pointer), Y
;; JSR to modified big_set ;; JSR to modified big_set
LDY length_copy LDY length_copy
DEY ; because we want to count to Y=0 :) DEY ; because we want to count to Y=0 :)
LDA data_to_write LDA data_to_write
JSR big_set JSR big_set
;; revert changes ;; revert changes
LDY Y_copy LDY Y_copy
TXA TXA
STA (RTS_pointer), Y STA (RTS_pointer), Y
RTS RTS
.endproc .endproc