Files
linguist/samples/Pep8/linked.pep
Lucas Bajolet ded651159d Add Pep8 Assembly language (#2070)
Pep/8 is a toy assembly language used in some universities for teaching
the basics of assembly and low-level programming.

Signed-off-by: Lucas Bajolet <lucas.bajolet@gmail.com>
2017-05-15 09:02:06 +01:00

676 lines
16 KiB
Plaintext

; Linked list of integers API
;
; Contains the basis of the structure and a
; variety of available functions to call on it.
;
; Calling conventions:
;
; - When the number of arguments is <= 2, the fastcall convention will be used:
; Arguments will be passed by registers, no assumption is made concerning the
; state of the registers during execution, they will need to be saved.
;
; - When the number of arguments exceeds 2, the cdecl convention will be used:
; Arguments will be passed on the stack, no assumption is made concerning the
; state of the registers during execution, they will need to be saved.
; Simple test program, do no include when using the library
main: SUBSP 4, i
DECI mnelmt, s
CALL newlst
LDX mnlst, s
CALL lstgetst
LDX mnlst, s
CALL lstsetst
LDX mnlst, s
CALL lstgetst
LDX mnlst, s
CALL shftest
LDX mnlst, s
CALL ushftest
LDX mnlst, s
CALL shftest
ADDSP 4, i
STOP
; Pointer to the list
mnlst: .EQUATE 0
; Element read
mnelmt: .EQUATE 2
; TESTS
; Simple test for the get operation
; Gets the first element of the list and prints it
;
; REQUIRES: Non-empty list
;
; Parameters:
; - X: Pointer to the list
;
; Returns:
; void
lstgetst: SUBSP 2, i
LDA 0, i
CALL lstget
STA 0, s
DECO 0, s
CHARO '\n', i
ADDSP 2, i
RET0
; Test for the set operation
; Sets the first element of the list to a given value
; The value is read from stdin
;
; REQUIRES: Non-empty list
;
; Parameters:
; - X: Pointer to the list
;
; Returns:
; void
lstsetst: SUBSP 6, i
STX 0, s
DECI 4, s
LDA 0, i
STA 2, s
CALL lstset
ADDSP 6, i
RET0
; Tests shift operation on a list
; Gets the last element of the list and prints it
;
; REQUIRES: Non-empty list
;
; Parameters:
; - X: Pointer to the list
;
; Returns:
; void
shftest: SUBSP 2, i
CALL lstshft
STA 0, s
DECO 0, s
CHARO '\n', i
ADDSP 2, i
RET0
; Tests unshift operation on a list
; Unshifts a new element read from keyboard
;
; Parameters:
; - X: Pointer to the list
;
; Returns:
; void
ushftest: SUBSP 2, i
DECI 0, s
LDA 0, s
CALL lstunshf
ADDSP 2, i
RET0
; LIBRARY
; Creates a new list with `element` as head
;
; Parameters:
; SP + 4: Element
;
; Returns:
; SP + 2: Pointer to the list
newlst: LDA lstlen, i
CALL new
STX 2, s
CALL newnode
SUBSP 2, i
STX 0, s
LDX nodeelmt, i
LDA 6, s
STA 0, sxf
LDA 0, s
LDX lsthead, i
STA 4, sxf
ADDSP 2, i
RET0
; Gets a node at specified index in a list
;
; Parameters:
; - A: Index
; - X: Pointer to the list
;
; Returns:
; - A: Error code (0 if no error was produced)
; - X: Pointer to the node
;
; Errors:
; -1: Index < 0
; -2: Index >= list.length
nodeat: SUBSP 10, i
STA ndaind, s
STX ndalst, s
LDX lsthead, i
LDA ndalst, sxf
STA ndanode, s
LDA ndaind, s
CPA 0, i
LDA 0, i
STA ndacurri, s
BRGE ndagez
LDA -1, i
ADDSP 10, i
RET0
ndagez: LDX ndalst, s
CALL listlen
STA ndalstln, s
LDA ndaind, s
CPA ndalstln, s
BRLT ndalp
LDA -2, i
ADDSP 10, i
RET0
ndalp: LDA ndacurri, s
CPA ndaind, s
BREQ ndaout
LDX nodenxt, i
LDA ndanode, sxf
STA ndanode, s
LDA ndacurri, s
ADDA 1, i
STA ndacurri, s
BR ndalp
ndaout: LDX ndanode, s
LDA 0, i
ADDSP 10, i
RET0
ndaind: .EQUATE 0
ndanode: .EQUATE 2
ndalst: .EQUATE 4
ndalstln: .EQUATE 6
ndacurri: .EQUATE 8
; Length of the list passed as a parameter
;
; Parameters:
; - X: List
;
; Returns:
; - A: Length
listlen: SUBSP 4, i
STX lenode, s
LDX lenode, sf
STX lenode, s
LDA 0, i
STA lencpt, s
llenlp: LDA lenode, s
CPA 0, i
BREQ lenout
LDA lencpt, s
ADDA 1, i
STA lencpt, s
LDX nodenxt, i
LDA lenode, sxf
STA lenode, s
BR llenlp
lenout: LDA lencpt, s
ADDSP 4, i
RET0
lenode: .EQUATE 0
lencpt: .EQUATE 2
; Gets an element in a list at a specified index
;
; Parameters:
; - A: Index
; - X: Address of the list
;
; Returns:
; - A: Element value
;
; Error:
; If out of bounds, prints an error message and stops the program
lstget: SUBSP 2, i
STA 0, s
CALL nodeat
CPA 0, i
BRNE getoob
LDA 0, x
ADDSP 2, i
RET0
; Out of bounds
getoob: STRO getstrob, d
DECO 0, s
CHARO '\n', i
STOP
; String for out of bounds error
getstrob: .ASCII "Invalid index on get, index = \x00"
; Sets an element in a list at a specified index to a new value
;
; Parameters:
; - SP + 2: Pointer to the list
; - SP + 4: Index
; - SP + 6: Element
;
; Returns:
; - A: 0 if all went well, an error code otherwise (analogous to the error codes in nodeat)
lstset: CHARO '\n', i
DECO lstsetlp, s
CHARO ' ', i
DECO lstsetin, s
CHARO ' ', i
DECO lstsetel, s
CHARO '\n', i
SUBSP 2, i
LDX lstsetlp, s
LDA lstsetin, s
CALL nodeat
CPA 0, i
BRNE lstsetrt
STX lstsetnp, s
LDA lstsetel, s
LDX nodeelmt, i
STA lstsetnp, sxf
LDA 0, i
lstsetrt: ADDSP 2, i
RET0
; Pointer to the list
lstsetlp: .EQUATE 4
; Element to set the value at
lstsetel: .EQUATE 8
; Index of the node
lstsetin: .EQUATE 6
; Pointer to the node
lstsetnp: .EQUATE 0
; Removes the first element of the list in parameter and returns its value
;
; REQUIRES: Non-empty list
;
; Parameters:
; ⁻ X: Pointer to the list
;
; Returns :
; - A: Element removed
lstshft: SUBSP 8, i
STX lshflp, s
LDX lsthead, i
LDA lshflp, sxf
CPA 0, i
BREQ shfterr
STA lshfohd, s
LDX nodenxt, i
LDA lshfohd, sxf
STA lshfnhd, s
LDX lsthead, i
STA lshflp, sxf
LDX nodeelmt, i
LDA lshfohd, sxf
ADDSP 8, i
RET0
shfterr: STRO shfterrm, d
STOP
; Pointer to the list
lshflp: .EQUATE 0
; Pointer to the old head
lshfohd: .EQUATE 2
; Old head's element
lshfhdel: .EQUATE 4
; Pointer to the new head
lshfnhd: .EQUATE 6
; Error message on shift
shfterrm: .ASCII "Cannot do shift on empty list.\n\x00"
; Inserts a new element at the beginning of a list
;
; Parameters:
; - X: Pointer to the list
; - A: Element to add to the list
;
; Returns:
; - A: Error code, 0 if all right, a code otherwise
lstunshf: SUBSP 8, i
STA lunshelm, s
STX lunslp, s
CALL newnode
STX lunsnhd, s
LDX lsthead, i
LDA lunslp, sxf
STA lunsohd, s
LDX nodenxt, i
LDA lunsohd, s
STA lunsnhd, sxf
LDA lunshelm, s
LDX nodeelmt, i
STA lunsohd, sxf
LDX lsthead, i
LDA lunsnhd, s
STA lunslp, sxf
ADDSP 8, i
RET0
; Pointer to the list
lunslp: .EQUATE 0
; Pointer to the old head
lunsohd: .EQUATE 2
; Pointer to the new head
lunsnhd: .EQUATE 4
; Element to add
lunshelm: .EQUATE 6
; Finds whether or not an element is present in a list
;
; Parameters:
; - X: Pointer to the list
; - A: Element to be found
;
; Returns:
; - A: 0 if element was not found, 1 if it was
lstfnd: SUBSP 6, i
STX lstfndlp, s
STA lstfndel, s
LDX lsthead, i
LDA lstfndlp, sxf
STA lstfndnd, s
fndloop: CPA 0, i
BREQ notfnd
LDX nodeelmt, i
LDA lstfndnd, sxf
CPA lstfndel, s
BREQ found
LDX nodenxt, i
LDA lstfndnd, sxf
STA lstfndnd, s
BR fndloop
notfnd: LDA 0, i
ADDSP 6, i
RET0
found: LDA 1, i
ADDSP 6, i
RET0
; Pointer to the list
lstfndlp: .EQUATE 0
; Element to search
lstfndel: .EQUATE 2
; Current node
lstfndnd: .EQUATE 4
; Pushes a new element at the end of the list
;
; Parameters:
; - X: Pointer to the list
; - A: Element to push
;
; Returns:
; - A: 0 if all went well, an error code otherwise
lstpsh: SUBSP 8, i
STX lpshlp, s
STA lpshel, s
CALL newnode
STX lpshnd, s
LDX lpshlp, s
CALL listlen
CPA 0, i
BREQ lpshshft
SUBA 1, i
LDX lpshlp, s
CALL nodeat
STX lpshlnd, s
LDX nodenxt, i
LDA lpshnd, s
STA lpshlnd, sxf
LDA lpshel, s
LDX nodeelmt, i
STA lpshnd, sxf
ADDSP 8, i
RET0
lpshshft: LDX lpshlp, s
LDA lpshel, s
CALL lstunshf
ADDSP 8, i
RET0
; Pointer to the list
lpshlp: .EQUATE 0
; Element to add to the list
lpshel: .EQUATE 2
; Node to add to the list
lpshnd: .EQUATE 4
; Node to append
lpshlnd: .EQUATE 6
; Pops the last element of a list
;
; Parameters:
; - X: Pointer to the list
;
; Returns:
; - A: Element removed from the list
lstpop: SUBSP 6, i
STX lpoplp, s
CALL listlen
CPA 0, i
BRNE poperrem
CPA 1, i
BREQ popshft
SUBA 2, i
LDX lpoplp, s
CALL nodeat
STX lpopndpr, s
LDX nodenxt, i
LDA lpopndpr, sxf
LDA 0, i
LDX nodenxt, i
STA lpopndpr, sxf
STA lpoplnd, s
LDX nodeelmt, i
LDA lpoplnd, s
ADDSP 6, i
RET0
poperrem: STRO poperrsm, d
STOP
popshft: LDX lpoplp, s
CALL lstshft
ADDSP 6, i
RET0
; Pointer to the list
lpoplp: .EQUATE 0
; Node to remove
lpoplnd: .EQUATE 2
;New last node
lpopndpr: .EQUATE 4
; Message to print when popping an empty list
poperrsm: .ASCII "Error: cannot pop an empty list.\n\x00"
; Inserts an element in a list at a given position
;
; REQUIRES: Non-empty list
;
; Parameters:
; - SP + 2: Pointer to the list
; - SP + 4: Index to insert at
; - SP + 6: Element to add
;
; Returns:
; - A: Error code: 0 if all went well, -1 if index < 0, -2 if index > list.length
lstinsat: SUBSP 6, i
LDA lstinsid, s
CPA 0, i
BRLT lstinslz
BREQ lstinush
LDX lstinslp, s
CALL listlen
CPA lstinsel, s
BRLT lstinsgl
BREQ lstinpsh
LDX lstinslp, s
LDA lstinsel, s
SUBA 1, i
CALL nodeat
STX lstinsnd, s
LDX nodenxt, i
LDA lstinsnd, sxf
STA lstinscx, s
CALL newnode
STX lstinscn, s
LDX nodeelmt, i
LDA lstinsel, s
STA lstinscn, sxf
LDX nodenxt, i
LDA lstinscx, s
STA lstinscn, sxf
LDA lstinscn, s
LDX nodenxt, i
STA lstinsnd, sxf
ADDSP 6, i
RET0
lstinush: LDX lstinslp, s
LDA lstinsel, s
CALL lstunshf
ADDSP 6, i
RET0
lstinpsh: LDX lstinslp, s
LDA lstinsel, s
CALL lstpsh
ADDSP 6, i
RET0
; Insert with index < 0
lstinslz: LDA -1, i
ADDSP 6, i
RET0
; Insert with index > list.length
lstinsgl: LDA -2, i
ADDSP 6, i
RET0
; List pointer
lstinslp: .EQUATE 8
; Index of the newly created node
lstinsid: .EQUATE 10
; Element to add
lstinsel: .EQUATE 12
; Node to change the pointer to the next
lstinsnd: .EQUATE 0
; Node to insert
lstinscn: .EQUATE 2
; Pointer to the node after the created one (might be null)
lstinscx: .EQUATE 4
; Removes a node at a given index in a list,
; returns the element previously contained
;
; Parameters:
; - X: Pointer to the list
; - A: Index of the element
;
; Returns:
; - A: Element removed
;
; Error:
; In case of error, the program aborts with an error message
lstremat: SUBSP 8, i
STX lremlp, s
STA lremid, s
CPA 0, i
BRLT lstremob
BREQ lstremz
CALL listlen
CPA lremid, s
BRGE lstremob
SUBA 1, i
CPA lremid, s
BREQ lrempop
LDA lremid, s
LDX lremlp, s
CALL nodeat
STX lremnd, s
LDA lremid, s
SUBA 1, i
LDX lremlp, s
CALL nodeat
STX lrempnd, s
LDX nodenxt, i
LDA lremnd, sxf
STA lrempnd, sxf
LDX nodeelmt, i
LDA lremnd, sxf
ADDSP 8, i
RET0
lstremz: LDX lremlp, s
CALL lstshft
ADDSP 8, i
RET0
lrempop: LDX lremlp, s
CALL lstpop
ADDSP 8, i
RET0
lstremob: STRO lremobst, d
DECO lremid, s
CHARO '\n', i
STOP
; Pointer to the list
lremlp: .EQUATE 0
; Index to remove an element at
lremid: .EQUATE 2
; Pointer to the node before the removed element
lrempnd: .EQUATE 4
; Pointer to the node to remove
lremnd: .EQUATE 6
; Error out of bounds string for remove_at
lremobst: .ASCII "Error: Out of bounds in remove_at, index = \x00"
; Creates a new node from scratch
; Sets its content to 0/NULL
;
; Parameters:
; void
;
; Return:
; - X: Address of the node
newnode: LDA nodeln, i
SUBSP 2, i
CALL new
STX 0, s
LDA 0, i
LDX nodenxt, i
STA 0, sxf
LDX nodeelmt, i
STA 0, sxf
LDX 0, s
ADDSP 2, i
RET0
; Allocates a new structure in the heap
;
; Parameters:
; - A: Length of the structure to allocate (bytes)
;
; Returns:
; - X: Address of the allocated structure
new: ADDA hpptr, d
LDX hpptr, d
STA hpptr, d
RET0
; Node in a linked list
;
; Contains two fields:
; - Element: Offset 0
; - Next: Offset 2
;
nodeln: .EQUATE 4
nodeelmt: .EQUATE 0
nodenxt: .EQUATE 2
; Linked list capsule
;
; Contains one field:
; - Head: Offset 0
;
lstlen: .EQUATE 2
lsthead: .EQUATE 0
; Pointer to the next available byte on the heap
hpptr: .ADDRSS heap
; Start of the heap
heap: .BLOCK 1
.END