ref: 4b789895db7cc077cd28fa71db93155f7410fbbd
parent: 0644f16baa668188060a03a5585bf7ea3443364a
author: 9ferno <gophone2015@gmail.com>
date: Fri Nov 19 16:04:08 EST 2021
using the memory map used by Starting Forth
--- a/os/pc64/forth.s
+++ b/os/pc64/forth.s
@@ -40,24 +40,32 @@
.. fn ;
Heap memory map: uses 8 pages at the start, will increase by *2 when filled up
-Variables
- system variables
+H0: variables
heap start, heapstart, also in H0
heap size, heapsize
forth stack pointer, forthsp
- dictionary top, dtop
+ dictionary pointer, Dp
+ latest dictionary entry, Dtop
+ need this as the system definitions and
+ user definitions are not continuous
error string buffer 128 bytes
word buffer 512 bytes
- tib, text input buffer 1024 bytes (until the next page?)
-User dictionary upto 6 pages from the start
-Return stack 1 page (4096 bytes, BY2PG, 512 entries) at FFSTART
+User dictionary upto pages from the start
|
|
v (grows downwards)
+ ^ (grows upwards)
+ |
+ |
Parameter stack 1 page (BY2PG, 512 entries) at FFEND-4096
+tib, text input buffer 1024 bytes (until the next page?)
+ |
+ |
+ v (grows downwards)
^ (grows upwards)
|
|
+Return stack 1 page (4096 bytes, BY2PG, 512 entries) at FFSTART
SSTACK_END = FORTHEND
*/
@@ -71,36 +79,45 @@
#define PSTACK_SIZE BY2PG
#define RSTACK_SIZE BY2PG
+/*
+ * user table at the start unlike in Starting Forth as it will be
+ * easy to get to the variables with an offset
+ */
#define HEAPSTART (0ull)
-#define HEAPEND (HEAPSTART+8)
-#define FORTHSP (HEAPSTART+16)
-#define DTOP (HEAPSTART+24)
+#define HEAPEND (HEAPSTART+(BY2WD*1))
+#define FORTHSP (HEAPSTART+(BY2WD*2))
+#define DP (HEAPSTART+(BY2WD*3)) /* cannot use H as it is nil in inferno
+ next available cell for the dictionary */
+#define DTOP (HEAPSTART+(BY2WD*4))
/* variables used by the core words */
-#define TOIN (HEAPSTART+32)
-#define TOLIMIT (HEAPSTART+40)
-#define FINDADR (HEAPSTART+48)
-#define BLK (HEAPSTART+56)
-#define ARGS (HEAPSTART+64)
-#define IOBUF (HEAPSTART+72)
-#define SEARCHLEN (HEAPSTART+80)
-#define BASE (HEAPSTART+88)
-#define TONUM (HEAPSTART+96)
-#define STATE (HEAPSTART+104)
-#define ABORTVEC (HEAPSTART+112)
-#define SOURCEBUF (HEAPSTART+120)
-#define WORDBUF (HEAPSTART+128)
-#define INFD (HEAPSTART+136)
-#define OUTFD (HEAPSTART+144)
-#define ERRFD (HEAPSTART+152)
+#define TOIN (HEAPSTART+(BY2WD*5))
+#define TOLIMIT (HEAPSTART+(BY2WD*6))
+#define FINDADR (HEAPSTART+(BY2WD*7))
+#define BLK (HEAPSTART+(BY2WD*8))
+#define ARGS (HEAPSTART+(BY2WD*9))
+#define IOBUF (HEAPSTART+(BY2WD*10))
+#define SEARCHLEN (HEAPSTART+(BY2WD*11))
+#define BASE (HEAPSTART+(BY2WD*12))
+#define TONUM (HEAPSTART+(BY2WD*13))
+#define STATE (HEAPSTART+(BY2WD*14))
+#define ABORTVEC (HEAPSTART+(BY2WD*15))
+#define SOURCEBUF (HEAPSTART+(BY2WD*16))
+#define WORDBUF (HEAPSTART+(BY2WD*17))
+#define INFD (HEAPSTART+(BY2WD*18))
+#define OUTFD (HEAPSTART+(BY2WD*19))
+#define ERRFD (HEAPSTART+(BY2WD*20))
-#define ERRSTR (HEAPSTART+160)
-#define WORDB (HEAPSTART+288) /* word buffer */
-#define TIB (HEAPSTART+792) /* text input buffer */
-#define DICTIONARY (HEAPSTART+2048)
+#define ERRSTR (HEAPSTART+(BY2WD*32))
+#define WORDB (HEAPSTART+(BY2WD*160)) /* word buffer */
+
+#define DICTIONARY (HEAPSTART+2048) /* dictionary */
#define DICTIONARY_END (HEAPSTART+(6*BY2PG))
-#define RSTACK (HEAPSTART+(6*BY2PG))
-#define PSTACK_END (RSTACK+(2*BY2PG))
-#define FORTHEND PSTACK_END
+#define PSTACK (HEAPSTART+(6*BY2PG))
+#define PSTACK_END (HEAPSTART+(7*BY2PG))
+#define TIB (HEAPSTART+(7*BY2PG)) /* text input buffer */
+#define RSTACK (HEAPSTART+(8*BY2PG))
+#define RSTACK_END (HEAPSTART+(9*BY2PG))
+#define FORTHEND RSTACK_END
#define HEAPSIZE FORTHEND
#define LAST $centry_c_boot(SB) /* last defined word, should generate this */
@@ -123,10 +140,11 @@
MOVQ RARG, H0 /* start of heap memory */
MOVQ H0, RSP
- ADDQ $RSTACK, RSP /* return stack pointer, reset */
+ ADDQ $RSTACK_END, RSP /* return stack pointer, reset */
MOVQ H0, PSP
- ADDQ $FORTHEND, PSP /* parameter stack pointer - stack setup, clear */
+ ADDQ $PSTACK_END, PSP /* parameter stack pointer - stack setup, clear */
+ MOVQ PSP, 16(H0) /* parameter stack pointer store, for forth to c */
MOVQ H0, TOP
ADDQ $HEAPSTART, TOP
@@ -134,8 +152,10 @@
ADDQ $(HEAPSIZE-1), TOP
MOVQ TOP, 8(H0) /* heap end */
- MOVQ PSP, 16(H0) /* parameter stack pointer */
- MOVQ $centry_c_boot(SB), 24(H0) /* Last dictionary entry address */
+ MOVQ H0, TOP
+ ADDQ $DICTIONARY, TOP
+ MOVQ TOP, 24(H0) /* dictionary pointer */
+ MOVQ $centry_c_boot(SB), 24(H0) /* Latest dictionary entry address */
/* execute boot */
MOVQ $centry_c_boot(SB), IP
@@ -162,33 +182,34 @@
MOVQ r, (PSP)
#define POP(r) MOVQ (PSP), r; \
ADDQ $8, PSP
+#define RPUSH(r) SUBQ $8, RSP; \
+ MOVQ r, (RSP)
+#define RPOP(r) MOVQ (RSP), r; \
+ ADDQ $8, RSP
NEXT
TEXT reset(SB), 1, $-4
MOVQ H0, RSP
- ADDQ $RSTACK, RSP
+ ADDQ $RSTACK_END, RSP
NEXT
TEXT clear(SB), 1, $-4
MOVQ H0, PSP
- ADDQ $FFEND, PSP
+ ADDQ $PSTACK_END, PSP
NEXT
TEXT colon(SB), 1, $-4
- MOVQ IP,(RSP)
- ADDQ $8, RSP
+ RPUSH(IP)
LEAQ 8(W), IP
NEXT
TEXT exitcolon(SB), 1, $-4
- SUBQ $8, RSP
- MOVQ (RSP), IP
+ RPOP(IP)
NEXT
TEXT dodoes(SB), 1, $-4 /* ( -- a ) */
- MOVQ IP,(RSP)
- ADDQ $8,RSP
+ RPUSH(IP)
MOVQ 8(W),IP
PUSH(TOP)
LEAQ 16(W), TOP
@@ -306,27 +327,25 @@
NEXT
TEXT doploop(SB), 1, $-4 /* ( n -- ) */
- ADDQ TOP, -16(RSP)
+ ADDQ TOP, 16(RSP)
POP(TOP)
JMP doloop1
-TEXT rfetch(SB), 1, $-4 /* ( -- n ) */
+TEXT rfetch(SB), 1, $-4 /* ( -- n ) no change in RSP */
PUSH(TOP)
- MOVQ -8(RSP), TOP
+ MOVQ (RSP), TOP
NEXT
-TEXT rpush(SB), 1, $-4 /* ( n -- ) */
- MOVQ TOP,(RSP)
- POP(TOP)
- ADDQ $8,RSP
- NEXT
-
TEXT rpop(SB), 1, $-4 /* ( -- n ) */
PUSH(TOP)
- SUBQ $8, RSP
- MOVQ (RSP), TOP
+ RPOP(TOP)
NEXT
+TEXT rpush(SB), 1, $-4 /* ( n -- ) */
+ RPUSH(TOP)
+ POP(TOP)
+ NEXT
+
TEXT i(SB), 1, $-4 /* ( -- n ) */
PUSH(TOP)
MOVQ -16(RSP), TOP
@@ -526,7 +545,7 @@
TEXT s0(SB), 1, $-4 /* S0 needs a calculation to come up with the value */
MOVQ H0, TOP
- ADDQ $FORTHEND, TOP
+ ADDQ $PSTACK_END, TOP
NEXT
/* store the forth sp here when going to C */
@@ -545,7 +564,8 @@
VARIABLE(Tib, $TIB)
VARIABLE(Wordb, $WORDB)
VARIABLE(Hzero, $HEAPSTART)
-VARIABLE(Dp, $DTOP)
+VARIABLE(Dp, $DP)
+VARIABLE(Dtop, $DTOP)
VARIABLE(toIn, $TOIN)
VARIABLE(toLimit, $TOLIMIT)
VARIABLE(Findadr, $FINDADR)
--- a/os/pc64/mem.h
+++ b/os/pc64/mem.h
@@ -206,4 +206,4 @@
#define RMACH R15 /* m-> */
#define RUSER R14 /* up-> */
-#define FORTHHEAPSIZE (8*BY2PG)
+#define FORTHHEAPSIZE (9*BY2PG)