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git-svn-id: svn://svn.cc65.org/cc65/trunk@3344 b7a2c559-68d2-44c3-8de9-860c34a00d81
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cuz 2005-01-05 20:05:27 +00:00
parent fd9226fe4a
commit d8fa43d7a6
1 changed files with 6 additions and 9 deletions
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15
libsrc/common/free.s
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@ -75,19 +75,16 @@ _free: sta ptr2
; Is the argument NULL? If so, bail out. ; Is the argument NULL? If so, bail out.
ora ptr2+1 ; Is the argument NULL? ora ptr2+1 ; Is the argument NULL?
bne @L0 ; Jump if no bne @L1 ; Jump if no
rts ; Bail out if yes rts ; Bail out if yes
; There's a pointer below the user space that points to the real start of the ; There's a pointer below the user space that points to the real start of the
; raw block. The first word of the raw block is the total size of the block. ; raw block. We will decrement the high pointer byte and use an offset of 254
; Remember the block size in ptr1. ; to save some code. The first word of the raw block is the total size of the
; block. Remember the block size in ptr1.
@L0: lda ptr2 @L1: dec ptr2+1 ; Decrement high pointer byte
sub #2 ldy #$FF
sta ptr2
bcs @L1
dec ptr2+1
@L1: ldy #1
lda (ptr2),y ; High byte of real block address lda (ptr2),y ; High byte of real block address
tax tax
dey dey