Use macpack for debugging, cosmetic changes

git-svn-id: svn://svn.cc65.org/cc65/trunk@171 b7a2c559-68d2-44c3-8de9-860c34a00d81

diff --git a/libsrc/common/free.s b/libsrc/common/free.s
index faa40c672a3b450f69509b2e7b24d2ef9a930703..8caf04d4b05318454d3db158919c6eeead2b5a6a 100644 (file)
--- a/libsrc/common/free.s
+++ b/libsrc/common/free.s
@@ -64,42 +64,46 @@
        .import         pushax, __hadd
        .export         _free
 
-; Offsets into struct freeblock
+       .macpack        generic
+
+; Offsets into struct freeblock and other constant stuff
+
+size           = 0
+next           = 2
+prev           = 4
+admin_space    = 2
+min_size       = 6
 
-       size    = 0
-       next    = 2
-       prev    = 4
 
 ; Code
 
 _free: sta     ptr1
-       stx     ptr1+1                  ; Save block
+       stx     ptr1+1                  ; Save block
 
 ; Is the argument NULL?
 
-       ora     ptr1+1                  ; Is the argument NULL?
-               beq     @L9                     ; Jump if yes
+       ora     ptr1+1                  ; Is the argument NULL?
+               beq     @L9                     ; Jump if yes
 
-; Decrement the given pointer by 2. The size of the block is stored there.
+; Decrement the given pointer by the admin space amount, so it points to the
+; real block allocated. The size of the block is stored in the admin space.
 ; Remember the block size in ptr2.
 
-       sec
        lda     ptr1
-       sbc     #2
+       sub     #admin_space
        sta     ptr1
        bcs     @L1
        dec     ptr1+1
 @L1:   ldy     #size+1
-       lda     (ptr1),y                ; High byte of size
-       sta     ptr2+1                  ; Save it
+       lda     (ptr1),y                ; High byte of size
+       sta     ptr2+1                  ; Save it
        dey
        lda     (ptr1),y
        sta     ptr2
 
 ; Check if the block is on top of the heap
 
-       clc
-       adc     ptr1
+       add     ptr1
        tay
        lda     ptr1+1
        adc     ptr2+1
@@ -126,12 +130,11 @@ _free:    sta     ptr1
        lda     __hlast+1
        sta     ptr2+1                  ; Pointer to last block now in ptr2
 
-       clc
        ldy     #size
        lda     (ptr2),y                ; Low byte of block size
-       adc     ptr2
+               add     ptr2
        tax
-       iny                             ; High byte of block size
+       iny                             ; High byte of block size
        lda     (ptr2),y
        adc     ptr2+1
 
@@ -151,14 +154,14 @@ _free:    sta     ptr1
 
        ldy     #prev+1                 ; Offset of ->prev field
                lda     (ptr2),y
-       sta     ptr1+1                  ; Remember f->prev in ptr1
+       sta     ptr1+1                  ; Remember f->prev in ptr1
        sta     __hlast+1
        dey
        lda     (ptr2),y
-       sta     ptr1                    ; Remember f->prev in ptr1
+       sta     ptr1                    ; Remember f->prev in ptr1
        sta     __hlast
-       ora     __hlast+1               ; -> prev == 0?
-               bne     @L8                     ; Jump if free list not empty
+       ora     __hlast+1               ; -> prev == 0?
+               bne     @L8                     ; Jump if free list not empty
 
 ; Free list is now empty (A = 0)
 
@@ -172,11 +175,11 @@ _free:    sta     ptr1
 ; Block before is now last block. ptr1 points to f->prev.
 
 @L8:   lda     #$00
-       dey                             ; Points to high byte of ->next
+       dey                             ; Points to high byte of ->next
        sta     (ptr1),y
-       dey                             ; Low byte of f->prev->next
+       dey                             ; Low byte of f->prev->next
        sta     (ptr1),y
-       rts                             ; Done
+       rts                             ; Done
 
 ; The block is not on top of the heap. Add it to the free list.
 
@@ -191,3 +194,4 @@ _free:      sta     ptr1
 
 
 
+