X-Git-Url: https://git.rrq.au/?a=blobdiff_plain;ds=sidebyside;f=temp.asm;h=932b1bb3e9e26bf4bf9d3fce01cbc231bbc171af;hb=cabd8413c10848728efcc2b869f631294f755d4d;hp=8e0be257f11e4f7bbf022d82dba366f94528141c;hpb=e5fe03259bcad1abf45257971eb92de95f269b1d;p=rrq%2Frrqforth.git

diff --git a/temp.asm b/temp.asm
index 8e0be25..932b1bb 100644
--- a/temp.asm
+++ b/temp.asm
@@ -1,16 +1,25 @@
-;;; 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.
+;;; Managing a memory area for temporary "objects".
 ;;;
+;;; Object space is allocated cyclically, starting subsequent to prior
+;;; allocation and cycling back when requested object size exceeds
+;;; the space edge. The "inital" part, which starts as empty, is
+;;; considered "held" space that is not reused when cycling back, and
+;;; apart from allowing for this, the space management is left open.
+
 
 	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 1073741824 ; [0] Total object space size (request size)
+	dq 0 ; [8] Object space base address.
+
+	WORD p_tempused,'TEMPUSED',dovariable
 	dq 0 ; [16] Currently used.
 
+	WORD p_tempheld,'TEMPHELD',dovariable
+	;; ( -- a )
+	;; Marks the barrier for "held space"
+	dq 0 ; [24] Currently held.
+
 	WORD p_temp,'TEMP',fasm
 	;; ( size -- addr )
 	;; Allocate an object of given size
@@ -22,18 +31,23 @@
 	DOFORTH p_malloc
 	pop qword [p_objectspace_DFA+8]
 p_objecthole_initialized:
+	mov rax,qword [p_tempheld_DFA]
+	cmp rax,qword [p_tempused_DFA]
+	jl p_objecthole_recycle
 	mov rax,qword [rsp]
-	add rax,qword [p_objectspace_DFA+16]
+	add rax,qword [p_tempused_DFA]
 	cmp rax,qword [p_objectspace_DFA]
 	jl p_objecthole_from_tail
-	mov qword [p_objectspace_DFA+16],0
-	mov rax,qword [rsp]
+	mov rax,qword [p_tempheld_DFA] ; cycling back to here
+p_objecthole_recycle:
+	mov qword [p_tempused_DFA],rax
+	add 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
+	mov rbx,qword [p_tempused_DFA]
 	add rbx,qword [p_objectspace_DFA+8]
 	mov qword [rsp],rbx
+	mov qword [p_tempused_DFA],rax
 	popr rsi
 	next