File: basics.fs

package info (click to toggle)
gforth 0.7.0+ds2-0.1
  • links: PTS, VCS
  • area: main
  • in suites: wheezy
  • size: 5,808 kB
  • sloc: ansic: 8,506; sh: 3,660; lisp: 1,783; makefile: 993; yacc: 186; sed: 141; lex: 102; awk: 21
file content (313 lines) | stat: -rw-r--r-- 8,720 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
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
162
163
164
165
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
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
\ kernel.fs    GForth kernel                        17dec92py

\ Copyright (C) 1995,1998,2000,2003,2004,2005,2006,2007 Free Software Foundation, Inc.

\ This file is part of Gforth.

\ Gforth is free software; you can redistribute it and/or
\ modify it under the terms of the GNU General Public License
\ as published by the Free Software Foundation, either version 3
\ of the License, or (at your option) any later version.

\ This program is distributed in the hope that it will be useful,
\ but WITHOUT ANY WARRANTY; without even the implied warranty of
\ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
\ GNU General Public License for more details.

\ You should have received a copy of the GNU General Public License
\ along with this program. If not, see http://www.gnu.org/licenses/.

\ Idea and implementation: Bernd Paysan (py)

\ Needs:

require ./vars.fs
require ../compat/strcomp.fs

hex

\ labels for some code addresses

\- NIL NIL AConstant NIL \ gforth

\ Aliases

[IFUNDEF] r@
' i Alias r@ ( -- w ; R: w -- w ) \ core r-fetch
[THEN]

\ !! this is machine-dependent, but works on all but the strangest machines

: maxaligned ( addr1 -- addr2 ) \ gforth
    \G @i{addr2} is the first address after @i{addr1} that satisfies
    \G all alignment restrictions.
    [ /maxalign 1 - ] Literal + [ 0 /maxalign - ] Literal and ;
\ !! machine-dependent and won't work if "0 >body" <> "0 >body
    \G maxaligned"
' maxaligned Alias cfaligned ( addr1 -- addr2 ) \ gforth
\G @i{addr2} is the first address after @i{addr1} that is aligned for
\G a code field (i.e., such that the corresponding body is maxaligned).

: chars ( n1 -- n2 ) \ core
\G @i{n2} is the number of address units of @i{n1} chars.""
; immediate


\ : A!    ( addr1 addr2 -- ) \ gforth
\    dup relon ! ;
\ : A,    ( addr -- ) \ gforth
\    here cell allot A! ;
' ! alias A! ( addr1 addr2 -- ) \ gforth

\ UNUSED                                                17may93jaw

has? ec [IF]
unlock ram-dictionary borders nip lock
AConstant dictionary-end
[ELSE]
    has? header [IF]
	: dictionary-end ( -- addr )
	    forthstart [ 3 cells image-header + ] Aliteral @ + ;
    [ELSE]
	: forthstart 0 ;
	: dictionary-end ( -- addr )
	    forthstart [ has? kernel-size ] Literal + ;
    [THEN]
[THEN]

: usable-dictionary-end ( -- addr )
    dictionary-end [ word-pno-size pad-minsize + ] Literal - ;

: unused ( -- u ) \ core-ext
    \G Return the amount of free space remaining (in address units) in
    \G the region addressed by @code{here}.
    usable-dictionary-end here - ;

has? ec [IF]
: in-dictionary? ( x -- f )
    dictionary-end u< ;
[ELSE]    
: in-dictionary? ( x -- f )
    forthstart dictionary-end within ;
[THEN]

\ here is used for pad calculation!

: dp    ( -- addr ) \ gforth
    dpp @ ;
: here  ( -- addr ) \ core
    \G Return the address of the next free location in data space.
    dp @ ;

\ on off                                               23feb93py

\ on is used by docol:
: on  ( a-addr -- ) \ gforth
    \G Set the (value of the) variable  at @i{a-addr} to @code{true}.
    true  swap ! ;
: off ( a-addr -- ) \ gforth
    \G Set the (value of the) variable at @i{a-addr} to @code{false}.
    false swap ! ;

\ dabs roll                                           17may93jaw

: dabs ( d -- ud ) \ double d-abs
    dup 0< IF dnegate THEN ;

: roll  ( x0 x1 .. xn n -- x1 .. xn x0 ) \ core-ext
    \  dup 1+ pick >r
    \  cells sp@ cell+ dup cell+ rot move drop r> ;
    dup 0<= if
	drop
    else
	swap >r 1- recurse r> swap 
    then ;

\ place bounds                                         13feb93py

: place  ( addr len to -- ) \ gforth
    over >r  rot over 1+  r> move c! ;
: bounds ( addr u -- addr+u addr ) \ gforth
    \G Given a memory block represented by starting address @i{addr}
    \G and length @i{u} in aus, produce the end address @i{addr+u} and
    \G the start address in the right order for @code{u+do} or
    \G @code{?do}.
    over + swap ;

\ (word)                                               22feb93py

: scan   ( addr1 n1 char -- addr2 n2 ) \ gforth
    \G skip all characters not equal to char
    >r
    BEGIN
	dup
    WHILE
	over c@ r@ <>
    WHILE
	1 /string
    REPEAT  THEN
    rdrop ;
: skip   ( addr1 n1 char -- addr2 n2 ) \ gforth
    \G skip all characters equal to char
    >r
    BEGIN
	dup
    WHILE
	over c@ r@  =
    WHILE
	1 /string
    REPEAT  THEN
    rdrop ;

\ digit?                                               17dec92py

: digit?   ( char -- digit true/ false ) \ gforth
  toupper [char] 0 - dup 9 u> IF
    [ char A char 9 1 + -  ] literal -
    dup 9 u<= IF
      drop false EXIT
    THEN
  THEN
  dup base @ u>= IF
    drop false EXIT
  THEN
  true ;

: accumulate ( +d0 addr digit - +d1 addr )
  swap >r swap  base @  um* drop rot  base @  um* d+ r> ;

: >number ( ud1 c-addr1 u1 -- ud2 c-addr2 u2 ) \ core to-number
    \G Attempt to convert the character string @var{c-addr1 u1} to an
    \G unsigned number in the current number base. The double
    \G @var{ud1} accumulates the result of the conversion to form
    \G @var{ud2}. Conversion continues, left-to-right, until the whole
    \G string is converted or a character that is not convertable in
    \G the current number base is encountered (including + or -). For
    \G each convertable character, @var{ud1} is first multiplied by
    \G the value in @code{BASE} and then incremented by the value
    \G represented by the character. @var{c-addr2} is the location of
    \G the first unconverted character (past the end of the string if
    \G the whole string was converted). @var{u2} is the number of
    \G unconverted characters in the string. Overflow is not detected.
    0
    ?DO
	count digit?
    WHILE
	accumulate
    LOOP
        0
    ELSE
	1- I' I -
	UNLOOP
    THEN ;

\ s>d um/mod						21mar93py

: s>d ( n -- d ) \ core		s-to-d
    dup 0< ;

: ud/mod ( ud1 u2 -- urem udquot ) \ gforth
    >r 0 r@ um/mod r> swap >r
    um/mod r> ;

\ catch throw                                          23feb93py

has? glocals [IF]
: lp@ ( -- addr ) \ gforth	lp-fetch
 laddr# [ 0 , ] ;
[THEN]

has? os 0= [IF]
    : catch  ( ... xt -- ... 0 )
	handler @ >r sp@ >r
	rp@ handler ! execute 0 r> drop r> handler ! ;
    : throw  ( error -- error )  dup 0= IF  drop EXIT  THEN
	handler @ rp! r> swap >r sp! r> r> handler ! ;
[ELSE]
defer catch ( x1 .. xn xt -- y1 .. ym 0 / z1 .. zn error ) \ exception
\G @code{Executes} @i{xt}.  If execution returns normally,
\G @code{catch} pushes 0 on the stack.  If execution returns through
\G @code{throw}, all the stacks are reset to the depth on entry to
\G @code{catch}, and the TOS (the @i{xt} position) is replaced with
\G the throw code.

:noname ( ... xt -- ... 0 )
    execute 0 ;
is catch

defer throw ( y1 .. ym nerror -- y1 .. ym / z1 .. zn error ) \ exception
\G If @i{nerror} is 0, drop it and continue.  Otherwise, transfer
\G control to the next dynamically enclosing exception handler, reset
\G the stacks accordingly, and push @i{nerror}.

:noname ( y1 .. ym error -- y1 .. ym / z1 .. zn error )
    ?dup if
	[ has? header [IF] here image-header 9 cells + ! [THEN] ]
	cr DoError cr
	[ has? file [IF] ] script? IF  1 (bye)  ELSE  quit  THEN
	[ [ELSE] ] quit [ [THEN] ]
    then ;
is throw
[THEN]

\ (abort")

: c(abort") ( c-addr -- )
    "error ! -2 throw ;

: (abort")
    "lit >r
    IF
	r> "error ! -2 throw
    THEN
    rdrop ;

: abort ( ?? -- ?? ) \ core,exception-ext
    \G @code{-1 throw}.
    -1 throw ;

\ ?stack                                               23feb93py

: ?stack ( ?? -- ?? ) \ gforth
    sp@ sp0 @ u> IF    -4 throw  THEN
[ has? floating [IF] ]
    fp@ fp0 @ u> IF  -&45 throw  THEN
[ [THEN] ]
;
\ ?stack should be code -- it touches an empty stack!

\ DEPTH                                                 9may93jaw

: depth ( -- +n ) \ core depth
    \G @var{+n} is the number of values that were on the data stack before
    \G @var{+n} itself was placed on the stack.
    sp@ sp0 @ swap - cell / ;

: clearstack ( ... -- ) \ gforth clear-stack
\G remove and discard all/any items from the data stack.
    sp0 @ sp! ;

: clearstacks ( ... -- ) \ gforth clear-stacks
\G empty data and FP stack
    clearstack
[ has? floating [IF] ]
    fp0 @ fp!
[ [THEN] ]
;

\ Strings						 22feb93py

: "lit ( -- addr )
  r> r> dup count + aligned >r swap >r ;

\ HEX DECIMAL                                           2may93jaw

: decimal ( -- ) \ core
    \G Set @code{base} to &10 (decimal).  Don't use @code{hex}, use
    \G @code{base-execute} instead.
    a base ! ;
: hex ( -- ) \ core-ext
    \G Set @code{base} to &16 (hexadecimal).  Don't use @code{hex},
    \G use @code{base-execute} instead.
    10 base ! ;