| ︙ | | |
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
-
+
|
assoc(`twodrop', `2DROP ')
assoc(`ntib', `#TIB ')
assoc(`tib', `TIB ')
assoc(`accept', `ACCEPT ')
assoc(`key', `KEY ')
assoc(`base', `BASE ')
assoc(`cmove', `CMOVE ')
assoc(`dbg', `DBG ')
assoc(`bye', `BYE ')
assoc(`drop', `DROP ')
assoc(`dup', `DUP ')
assoc(`emit', `EMIT ')
assoc(`evaluate', `EVALUATE')
assoc(`execute', `EXECUTE ')
assoc(`exit', `EXIT ')
assoc(`fill', `FILL ')
|
| ︙ | | |
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
|
assoc(`cstore', `C! ')
assoc(`plussto', `+! ')
assoc(`mult', `* ')
assoc(`minus', `- ')
assoc(`plus', `+ ')
assoc(`store', `! ')
assoc(`fetch', `@ ')
assoc(`pad', `PAD ')
assoc(`hld', `HLD ')
assoc(`hold', `HOLD ')
assoc(`todigit', `>DIGIT ')
assoc(`nstart', `<# ')
assoc(`nnn', `# ')
assoc(`nns', `#S ')
assoc(`nend', `#> ')
assoc(`umdivmod', `UM/MOD ')
assoc(`udot', `U. ')
assoc(`dot', `. ')
assoc(`is_lt0', `0< ')
assoc(`abs', `ABS ')
assoc(`hex', `HEX ')
assoc(`decimal', `DECIMAL ')
assoc(`binary', `BINARY ')
; DX-Forth is intended to be loaded at address $14200, and not
; exceed $17FFF. The dictionary space is intended to occupy
; from $18000-$1BFFF. Somewhere in this space must also exist
; things like the Forth stacks and block buffers.
;
; The following memory map crudely represents the memory layout
|
| ︙ | | |
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
|
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
-
+
+
+
|
; Execute the next Forth virtual instruction.
next: lhu W,0(I)
addi I,I,2
add W,W,D
jalr x0,0(W)
dbg: jalr x0,0(x0)
|
| ︙ | | |
426
427
428
429
430
431
432
433
434
435
436
437
438
439
|
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
|
+
+
+
+
+
+
+
+
|
align 4
_is_lt:
ld W,0(S)
addi S,S,8
blt W,T,_rtnT
_rtnF: addi T,x0,0
jal x0,next
; Sets T to -1 if T<0; 0 otherwise.
align 4
_is_lt0:
blt T,x0,_rtnT
addi T,x0,0
jal x0,next
; Bitwise AND, OR, XOR.
align 4
__and:
ld W,0(S)
addi S,S,8
|
| ︙ | | |
456
457
458
459
460
461
462
463
464
465
466
467
468
469
|
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
|
+
+
+
+
|
align 4
_negate:
xori T,T,-1
addi T,T,1
jal x0,next
align 4
_abs: blt T,x0,_negate
jal x0,next
align 4
__2star:
slli T,T,1
jal x0,next
align 4
__2slash:
|
| ︙ | | |
703
704
705
706
707
708
709
710
711
712
713
714
715
716
|
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
|
+
+
+
+
+
+
+
+
+
+
+
+
|
ld t1, 32(sp)
ld t2, 40(sp)
ld t3, 48(sp)
addi sp, sp, 56
jalr x0, 0(ra)
; End routines.
; UM/MOD ( ud u -- r q )
align 4
_umdivmod:
addi a2,T,0
ld a1,0(S)
ld a0,8(S)
jal ra,mathUDivMod
sd a1,8(S)
addi S,S,8
jal x0,next
; M* ( a b -- a*b.L a*b.H )
;
; This implementation isn't particularly efficient. But,
; it should be correct.
align 4
|
| ︙ | | |
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
|
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
|
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
|
jal W,_docol
hword over, plus, end, store
hword dup, strt, store, cur, store
_accept_0:
hword key, bs, c_c, c_m, gr, drop, go, _accept_0 - _start
; END ACCEPT
; BEGIN PICTURED NUMERIC OUTPUT
align 4
_pad: jal W,_docol
hword lit32
align 4
word _quit_0 + 256 + $14200 ; Base this on HERE when we implement it.
hword exit
align 4
_hld: jal W,_dovar
align 8
dword 0
align 4
_hold: jal W,_docol
hword lit16, -1, hld, plussto, hld, fetch, cstore, exit
align 4
_todigit:
jal W,_docol
hword dup, lit16, 10, is_geu, zgo, _todigit_0
hword lit16, 7, plus
_todigit_0:
hword lit16, $30, plus, exit
align 4
_nstart:
jal W,_docol
hword pad, hld, store, exit
align 4
_nend: jal W,_docol
hword drop, hld, fetch, pad, over, minus, exit
align 4
_nnn: jal W,_docol ; nn: is taken elsewhere.
hword lit16, 0, base, fetch, umdivmod, swap, todigit, hold, exit
align 4
_nns: jal W,_docol
_nns_0: hword dup, zgo, _nns_1, nnn, go, _nns_0
_nns_1: hword exit
align 4
_udot: jal W,_docol
hword nstart, nns, nend, type, exit
align 4
_dot: jal W,_docol
hword dup, is_lt0, tor, abs, nstart, nns, rfrom
hword zgo, _dot_0, lit16, $2D, hold
_dot_0: hword nend, type, exit
; END PICTURED NUMERIC OUTPUT
; ==== Look stuff up in the dictionary.
;
; The dictionary is a mapping of word name to code field
; address (CFA). The dictionary is expressed as a relational
; table with the following schema:
;
|
| ︙ | | |
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
|
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
|
+
+
+
+
+
+
+
+
+
+
+
+
+
+
|
hword exit
align 4
_base: jal W,_dovar
align 8
dword 10
align 4
_hex: jal W,_docol
hword lit16, 16, base, store, exit
align 4
_decimal:
jal W,_docol
hword lit16, 10, base, store, exit
align 4
_binary:
jal W,_docol
hword lit16, 2, base, store, exit
align 4
sign = _sign - _start
_sign: jal W,_dovar
align 8
dword 0
align 4
|
| ︙ | | |
1507
1508
1509
1510
1511
1512
1513
1514
|
1619
1620
1621
1622
1623
1624
1625
|
-
|
hword type, cr, exit
align 4
_quit: lui R,$14000 ; Hard reset of return stack.
jal W,_docol
_quit_0:
hword cr, rep, go, _quit_0
|