;;; Managing a memory area for temporary objects
;;;
;;; A temporary object space is allocated from the current usage
;;; level, or cycling back to be from the lowest space address when
;;; the requested size exceeds the space edge.
;;;

	WORD p_objectspace,'TEMPSPACE',dovariable
	;; Holds size and address of the object space.
	dq 104857600 ; [0] Total object space size (request size)
	dq 0 ; [8] Object space base address
	dq 0 ; [16] Currently used.

	WORD p_temp,'TEMP',fasm
	;; ( size -- addr )
	;; Allocate an object of given size
	pushr rsi
	cmp qword [p_objectspace_DFA+8],0
	jg p_objecthole_initialized
	;; initialize object space
	push qword [p_objectspace_DFA]
	DOFORTH p_malloc
	pop qword [p_objectspace_DFA+8]
p_objecthole_initialized:
	mov rax,qword [rsp]
	add rax,qword [p_objectspace_DFA+16]
	cmp rax,qword [p_objectspace_DFA]
	jl p_objecthole_from_tail
	mov qword [p_objectspace_DFA+16],0
	mov rax,qword [rsp]
p_objecthole_from_tail:
	;; rax = new usage count
	mov rbx,qword [p_objectspace_DFA+16]
	mov qword [p_objectspace_DFA+16],rax
	add rbx,qword [p_objectspace_DFA+8]
	mov qword [rsp],rbx
	popr rsi
	next

	WORD p_str2temp,'STR>TEMP',fasm
	;; ( char* n -- char* n )
	;; Capture a given [n:char*] string as a new temp object with
	;; leading size cell.
	pushr rsi
	mov rax,qword [rsp]
	add rax,8
	push rax
	DOFORTH p_temp		; ( -- char* n  addr )
	pop rax
	pop rbx
	mov qword[rax],rbx
	add rax,8
	pop rcx
	push rax
	push rbx
	push rcx
	push rax
	push rbx		; ( -- addr n char* addr n )
	DOFORTH p_strncpy
	popr rsi
	next