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Fixed the result of the % operator for ints

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git-svn-id: svn://svn.cc65.org/cc65/trunk@1408 b7a2c559-68d2-44c3-8de9-860c34a00d81
This commit is contained in:
cuz 2002-09-28 19:41:00 +00:00
parent 293bb88188
commit 3aab67401e
3 changed files with 44 additions and 32 deletions
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25
libsrc/runtime/div.s
View File

@ -8,15 +8,30 @@
; values if $8000, in which case the negate will fail.
.export tosdiva0, tosdivax
.import popsargs, udiv16, adjsres
.importzp sreg
.import popsargs, udiv16, negax
.importzp sreg, tmp1, tmp2
tosdiva0:
ldx #0
tosdivax:
jsr popsargs ; Get arguments from stack, adjust sign
jsr udiv16 ; Do the division
lda sreg ; Result is in sreg, remainder in ptr1
ldx sreg+1
jmp adjsres ; Adjust the sign of the result if needed
ldx sreg+1 ; Load high byte of result
; Adjust the sign of the result. tmp1 contains the high byte of the left
; operand, tmp2 contains the high byte of the right operand.
lda tmp1
eor tmp2
bpl Pos ; Jump if sign of result positive
; Result is negative
lda sreg ; Load low byte of result
jmp negax ; Adjust the sign
; Result is positive
Pos: lda sreg
rts

25
libsrc/runtime/mod.s
View File

@ -8,16 +8,31 @@
; values if $8000, in which case the negate will fail.
.export tosmoda0, tosmodax
.import popsargs, udiv16, adjsres
.importzp ptr1
.import popsargs, udiv16, negax
.importzp ptr1, tmp1
tosmoda0:
ldx #0
tosmodax:
jsr popsargs ; Get arguments from stack, adjust sign
jsr udiv16 ; Do the division
lda ptr1 ; Result is in sreg, remainder in ptr1
ldx ptr1+1
jmp adjsres ; Adjust the sign of the result if needed
ldx ptr1+1 ; Load high byte of result
; Adjust the sign of the result. tmp1 contains the high byte of the left
; operand, tmp2 contains the high byte of the right operand. The sign of
; the result of the modulo operation is the same as that of the left
; operand
lda tmp1
bpl Pos ; Jump if sign of result positive
; Result is negative
lda ptr1 ; Load low byte of result
jmp negax ; Adjust the sign
; Result is positive
Pos: lda ptr1
rts

26
libsrc/runtime/shelp.s
View File

@ -7,12 +7,12 @@
; When negating values, we will ignore the possibility here, that one of the
; values if $8000, in which case the negate will fail.
.export popsargs, adjsres
.export popsargs
.import negax, popax
.importzp sreg, tmp1, tmp2, ptr4
popsargs:
stx tmp1 ; Remember sign
stx tmp2 ; Remember sign
cpx #0
bpl L1
jsr negax ; Negate accumulator
@ -20,29 +20,11 @@ L1: sta ptr4
stx ptr4+1 ; Save right operand
jsr popax
stx tmp2 ; Remember sign
stx tmp1 ; Remember sign
cpx #0
bpl L2
jsr negax
L2: sta sreg
stx sreg+1
; Calculate the sign of the result, that is sign(op1) * sign(op2)
lda tmp1
eor tmp2
sta tmp2 ; Save it across call
L3: rts
; Adjust the result of a mod/div/mul operation
adjsres:
; Check if we must adjust the sign
ldy tmp2
bpl L3
jmp negax ; Adjust sign
rts