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Optimize a negation in signed division.

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This commit is contained in:
Piotr Fusik 2019-11-05 20:15:34 +01:00 committed by Oliver Schmidt
parent 0d21a2b5a4
commit 2bec637637
1 changed files with 5 additions and 6 deletions
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11
libsrc/runtime/idiv32by16r16.s
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@ -29,19 +29,18 @@ idiv32by16r16:
stx ptr3+1 stx ptr3+1
lda ptr2+1 lda ptr2+1
cmp #$80
eor tmp1 eor tmp1
sta tmp1 sta tmp1
bit ptr2+1 bcc @L3
bpl @L3
; Negate the value in ptr1:ptr2 ; Negate the value in ptr1:ptr2
ldx #0 ldx #0
ldy #4 ldy #4
sec ; sec
@L2: lda ptr1,x @L2: lda #$00
eor #$FF sbc ptr1,x
adc #$00
sta ptr1,x sta ptr1,x
inx inx
dey dey