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Thorham · 09 December 2013, 15:51

To AGS:

Some suggestions:

I've seen numerous instances of the following kind of code in your code:

Code:

    cmp.l   #bla.a1,d0
    bne     .l1
    move.l  d1,bla.a1(a0)
.l1
    cmp.l   #bla.a2,d0
    bne     .l2
    move.l  d1,bla.a2(a0)
.l2
    cmp.l   #bla.a3,d0
    bne     .l3
    move.l  d1,bla.a3(a0)
.l3

It's better to try and write it like this, because it's faster, shorter and far less prone to errors:

Code:

    move.l  d1,(a0,d0.w*4)  ; for long words
    move.w  d1,(a0,d0.w*2)  ; for words
    move.b  d1,(a0,d0.w)    ; for bytes

I've also seen multiple instances of inlined linked list code and what appears to be code that traverses a whole list to get the last node in the list. A better approach would be to do something like this (excuse the use of rs.l, I haven't looked at the types include

):

Code:

    
            rsreset
list.first  rs.l 1  ; pointer to first node in list
list.last   rs.l 1  ; pointer to last node in list
struct_list rs.l 1  ; size of structure
    
            rsreset
node.prev   rs.l 1  ; pointer to previous node
node.next   rs.l 1  ; pointer to next node
struct_node rs.l 1  ; size of structure

list.add            ; add node to list
list.insert         ; insert node between two nodes
list.delete         ; delete node from list

In the case of the methods (add, insert and delete) you simply keep list.last pointing to the last node. No slow loops required.

Using only one set of linked list routines is far easier and less error prone than inlining the code wherever it's needed.

09 December 2013, 15:51	#17
Thorham Computer Nerd Join Date: Sep 2007 Location: Rotterdam/Netherlands Age: 47 Posts: 3,767	To AGS: Some suggestions: I've seen numerous instances of the following kind of code in your code: Code: cmp.l #bla.a1,d0 bne .l1 move.l d1,bla.a1(a0) .l1 cmp.l #bla.a2,d0 bne .l2 move.l d1,bla.a2(a0) .l2 cmp.l #bla.a3,d0 bne .l3 move.l d1,bla.a3(a0) .l3 It's better to try and write it like this, because it's faster, shorter and far less prone to errors: Code: move.l d1,(a0,d0.w4) ; for long words move.w d1,(a0,d0.w2) ; for words move.b d1,(a0,d0.w) ; for bytes I've also seen multiple instances of inlined linked list code and what appears to be code that traverses a whole list to get the last node in the list. A better approach would be to do something like this (excuse the use of rs.l, I haven't looked at the types include ): Code: rsreset list.first rs.l 1 ; pointer to first node in list list.last rs.l 1 ; pointer to last node in list struct_list rs.l 1 ; size of structure rsreset node.prev rs.l 1 ; pointer to previous node node.next rs.l 1 ; pointer to next node struct_node rs.l 1 ; size of structure list.add ; add node to list list.insert ; insert node between two nodes list.delete ; delete node from list In the case of the methods (add, insert and delete) you simply keep list.last pointing to the last node. No slow loops required. Using only one set of linked list routines is far easier and less error prone than inlining the code wherever it's needed. Last edited by Thorham; 09 December 2013 at 15:56.