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Sqeezed a few bytes out of the copydata function

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git-svn-id: svn://svn.cc65.org/cc65/trunk@3320 b7a2c559-68d2-44c3-8de9-860c34a00d81
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cuz
2004-12-01 12:00:50 +00:00
parent 0ab513b254
commit 6de079ee57
1 changed files with 22 additions and 26 deletions
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48
libsrc/common/copydata.s
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@@ -1,53 +1,49 @@
; ;
; Ullrich von Bassewitz, 07.12.1998 ; Ullrich von Bassewitz, 1998-12-07, 2004-12-01
; ;
; Copy the data segment from the LOAD to the RUN location ; Copy the data segment from the LOAD to the RUN location
; ;
.export copydata .export copydata
.import __DATA_LOAD__, __DATA_RUN__, __DATA_SIZE__ .import __DATA_LOAD__, __DATA_RUN__, __DATA_SIZE__
.importzp ptr1, ptr2 .importzp ptr1, ptr2, tmp1
copydata: copydata:
lda #<__DATA_LOAD__ ; Source pointer lda #<__DATA_LOAD__ ; Source pointer
sta ptr1 sta ptr1
lda #>__DATA_LOAD__ lda #>__DATA_LOAD__
sta ptr1+1 sta ptr1+1
lda #<__DATA_RUN__ ; Target pointer lda #<__DATA_RUN__ ; Target pointer
sta ptr2 sta ptr2
lda #>__DATA_RUN__ lda #>__DATA_RUN__
sta ptr2+1 sta ptr2+1
ldy #$00 ldx #<~__DATA_SIZE__
ldx #>__DATA_SIZE__ ; Get page count lda #>~__DATA_SIZE__ ; Use -(__DATASIZE__+1)
beq @L2 ; No full pages sta tmp1
ldy #$00
; Copy full pages ; Copy loop
@L1: lda (ptr1),y @L1: inx
sta (ptr2),y beq @L3
iny
bne @L1
inc ptr1+1
inc ptr2+1 ; Bump pointers
dex
bne @L1
; Copy last page (remember: y contains zero) @L2: lda (ptr1),y
sta (ptr2),y
iny
bne @L1
inc ptr1+1
inc ptr2+1 ; Bump pointers
bne @L1 ; Branch always (hopefully)
@L2: ldx #<__DATA_SIZE__ ; Get remaining bytes ; Bump the high counter byte
beq @L4
@L3: lda (ptr1),y @L3: inc tmp1
sta (ptr2),y bne @L2
iny
dex
bne @L3
; Done ; Done
@L4: rts rts