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89 lines
1.1 KiB
ArmAsm
89 lines
1.1 KiB
ArmAsm
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; Ullrich von Bassewitz, 05.08.1998
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; CC65 runtime: long conversion routines
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;
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; Convert TOS from long to int by cutting of the high 16bit
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;
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.export tosint, tosulong, toslong, axulong, axlong
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.import incsp2, decsp2
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.importzp sp, sreg
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tosint: pha
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ldy #0
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lda (sp),y ; sp+1
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ldy #2
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sta (sp),y
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ldy #1
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lda (sp),y
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ldy #3
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sta (sp),y
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pla
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jmp incsp2 ; Drop 16 bit
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;
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; Convert TOS from int to long
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;
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tosulong:
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pha
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jsr decsp2 ; Make room
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ldy #2
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lda (sp),y
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ldy #0
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sta (sp),y
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ldy #3
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lda (sp),y
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ldy #1
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sta (sp),y
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lda #0 ; Zero extend
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toslong2:
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iny
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sta (sp),y
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iny
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sta (sp),y
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pla
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rts
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toslong:
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pha
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jsr decsp2 ; Make room
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ldy #2
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lda (sp),y
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ldy #0
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sta (sp),y
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ldy #3
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lda (sp),y
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bmi toslong1
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ldy #1
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sta (sp),y
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lda #$00 ; Positive, high word is zero
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bne toslong2
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toslong1:
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ldy #1
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sta (sp),y
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lda #$FF
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bne toslong2
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;
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; Convert AX from int to long in EAX
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;
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axulong:
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ldy #0
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sty sreg
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sty sreg+1
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rts
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axlong: cpx #$80 ; Positive?
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bcc axulong ; Yes, handle like unsigned type
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ldy #$ff
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sty sreg
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sty sreg+1
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rts
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