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fix range checks

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This commit is contained in:
Brooke Vibber 2023-01-22 13:56:19 -08:00
parent 0afed893a6
commit 7009e16235
1 changed files with 6 additions and 9 deletions
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15
mandel.s
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@ -434,15 +434,15 @@ loop:
rts
keep_going:
.macro quick_exit arg
.macro quick_exit arg, max
.local keep_going
.local keep_going2
lda arg + 1
cmp #(4 << 4)
cmp #((max) << 4)
bmi keep_going
rts
keep_going:
cmp #(256 - (4 << 4))
cmp #(256 - ((max) << 4))
bpl keep_going2
rts
keep_going2:
@ -452,28 +452,25 @@ keep_going:
; zx = zx_2 - zy_2 + cx
sub16 zx, zx_2, zy_2
add16 zx, zx, cx
quick_exit zx
quick_exit zx, 2
; zy = zx_zy + zx_zy + cy
add16 zy, zx_zy, zx_zy
add16 zy, zy, cy
quick_exit zy
quick_exit zy, 2
; zx_2 = zx * zx
imul16_round zx_2, zx, zx, 4
quick_exit zx_2
; zy_2 = zy * zy
imul16_round zy_2, zy, zy, 4
quick_exit zy_2
; zx_zy = zx * zy
imul16_round zx_zy, zx, zy, 4
quick_exit zx_zy
; dist = zx_2 + zy_2
add16 dist, zx_2, zy_2
quick_exit dist
quick_exit dist, 4
; if may be in the lake, look for looping output with a small buffer
; as an optimization vs running to max iters