IFND POWERPC_LISTSPPC_I
POWERPC_LISTSPPC_I      SET 1
**
**      $VER: ListsPPC.i 12.0 (1.8.97)
**      WarpOS Release 1.0
**
**      '(C) Copyright 1997 Haage & Partner Computer GmbH'
**      All Rights Reserved
**
**      Structures related to WarpOS list handling
**

                IFND    EXEC_LISTS_I
                include exec/lists.i
                ENDC

                IFND    EXEC_NODES_I
                include exec/nodes.i
                ENDC

                IFND    POWERPC/PPCMACROS_I
                include powerpc/ppcmacros.i
                ENDC

;Prepare a list header for use
_NEWLIST    MACRO   ; list
            STW     \1,LH_TAILPRED(\1)
            LI      R0,0
            STWU    R0,LH_TAIL(\1) ;Clear LH_TAIL
            STWU    \1,-4(\1)   ;Address of LH_TAIL to LH_HEAD
            ENDM

;Test if list is empty (list address in register)
;This operation is safe at any time - no list arbitration needed.
_TSTLIST    MACRO   ; [list]
            IFGT    NARG-1
               FAIL    !!! TSTLIST - Too many arguments !!!
            ENDC
            LWZ     R0,LH_TAIL+LN_PRED(\1)
            CMPW    R0,\1
            ENDM

;Get next in list
_SUCC       MACRO   ; node,=succ
            LWZ     \2,LN_SUCC(\1)
            ENDM

;Get previous in list
_PRED       MACRO   ; node,=pred
            LWZ     \2,LN_PRED(\1)
            ENDM

;If empty, branch
_IFEMPTY    MACRO   ; list,label
            LWZ     R0,LH_TAIL+LN_PRED(\1)
            CMPW    R0,\1
            BEQ     \2
            ENDM

;If not empty, branch
_IFNOTEMPTY MACRO   ; list,label
            LWZ     R0,LH_TAIL+LN_PRED(\1)
            CMPW    R0,\1
            BNE     \2
            ENDM

;Get next node, test if at end
_TSTNODE    MACRO   ; node,=next
            LWZ     \2,0(\1)
            LWZ     R0,(\2)
            MR.     R0,R0
            ENDM

;Add to head of list
_ADDHEAD    MACRO   ; r4-list r5-node r3-(destroyed)
            LWZ     r3,LH_HEAD(r4)
            STW     r5,LH_HEAD(r4)
            STW     r3,LN_SUCC(r5)
            STW     r4,LN_PRED(r5)
            STW     r5,LN_PRED(r3)
            ENDM

;Add to tail of list
_ADDTAIL    MACRO   ; r4-list(destroyed) r5-node r3-(destroyed)
            ADDI    r4,r4,LH_TAIL
            LWZ     r3,LN_PRED(r4)
            STW     r5,LN_PRED(r4)
            STW     r4,LN_SUCC(r5)
            STW     r3,LN_PRED(r5)
            STW     r5,LN_SUCC(r3)
            ENDM

;Remove node from whatever list it is in
_REMOVE     MACRO   ; r3-(destroyed) r4-node(destroyed)
            LWZ     r3,LN_SUCC(r4)
            LWZ     r4,LN_PRED(r4)
            STW     r4,LN_PRED(r3)
            STW     r3,LN_SUCC(r4)
            ENDM

;Remove node from head of list
_REMHEAD    MACRO   ; r4-list r5-destroyed r3-(returned: node removed)
            LWZ     r5,LH_HEAD(r4)
            LWZ     r3,LN_SUCC(r5)
            MR.     r3,r3
            BEQ     .REMHEAD\@
            STW     r3,LH_HEAD(r4)
            STW     r4,LN_PRED(r3)
            MR      r3,r5
.REMHEAD\@
            ENDM

;Remove node from tail of list
_REMTAIL    MACRO   ; r4-list r5-destroyed r3-(returned: node removed)
            LWZ     r5,LH_TAIL+LN_PRED(r4)
            LWZ     r3,LN_PRED(r5)
            MR.     r3,r3
            BEQ     .REMTAIL\@
            STW     r3,LH_TAIL+LN_PRED(r4)
            ADDI    r4,r4,LH_TAIL
            STW     r4,LN_SUCC(r3)
            MR      r3,r5
.REMTAIL\@
            ENDM

        ENDC    ;LISTSPPC_I