Implementing figFORTH on SH3 assembler
Révision | deab3b82bdeda15f36b40adf7a9e29e5471a6203 (tree) |
---|---|
l'heure | 2014-03-17 21:13:31 |
Auteur | Joel Matthew Rees <reiisi@user...> |
Commiter | Joel Matthew Rees |
Through ?STACK.
May be my last edits for a while -- I've run out of time.
@@ -203,6 +203,26 @@ _fDOUSER: | ||
203 | 203 | .data.l SEMIS |
204 | 204 | |
205 | 205 | |
206 | +; 0, ( n --- ) | |
207 | +; Add NULs to the dictionary, to the alignment boundary. | |
208 | +; | |
209 | + HIHEADER "0,", NULCOMMA, DOCOL | |
210 | + mov.l @(XDP,fUP), r0 ; XDP is within range. | |
211 | + mov.l r0, r1 | |
212 | + mALIGNr0 | |
213 | + mov #0, r2 | |
214 | +NULCOMMAloop: | |
215 | + cmp/hi r1, r0 ; aligned in r0 higher than r1? | |
216 | + bf NULCOMMAend | |
217 | + mov.b r2, @r1 | |
218 | + bra NULCOMMAloop | |
219 | + add #1, r1 | |
220 | +; | |
221 | +NULCOMMAend: | |
222 | + mov.l r0, @(XDP,fUP) | |
223 | + rts | |
224 | + | |
225 | + | |
206 | 226 | ; , ( n --- ) |
207 | 227 | ; Store natural word n at DP+. |
208 | 228 | ; (Store and allocate, which is the wrong order for things.) |
@@ -318,6 +338,173 @@ COMPILE_MODE: .equ h'C0 | ||
318 | 338 | .data.l SEMIS |
319 | 339 | |
320 | 340 | |
341 | + | |
342 | +; (;CODE) ( --- ) ( IP *** ) C | |
343 | +; Compile the latest symbol as a reference to a ;CODE definition. | |
344 | +; Overwrite the code field of the symbol referenced by LATEST | |
345 | +; with a jump to the low-level characteristic code provided | |
346 | +; in the defining definition. | |
347 | +; The machine-level code which follows (;CODE) in the | |
348 | +; instruction stream is not executed by the defining symbol, | |
349 | +; but becomes the characteristic of the defined symbol. See ;CODE. | |
350 | +; | |
351 | +; Note that IP is popped in the process, | |
352 | +; so the assembler level code (or machine code) | |
353 | +; which follows ;CODE is assembled in interpretive mode. | |
354 | +; | |
355 | + HIHEADER "(;CODE)", PSCODE, DOCOL | |
356 | + .data.l FROMR,NATPLUS,LATEST,PFA,CFA,STORE | |
357 | + .data.l SEMIS | |
358 | + | |
359 | + | |
360 | +; ;CODE ( --- ) P,C | |
361 | +; { : name preparatory-stuff ;CODE defining-machine-level-code C, .... } or | |
362 | +; { : name preparatory-stuff ;CODE defining-assembler-code .... } typical use | |
363 | +; ?CSP to see if there are loose ends in the defining definition | |
364 | +; before shifting to the assembler, compile (;CODE) | |
365 | +; in the defining definition's instruction stream, | |
366 | +; shift to interpreting. | |
367 | +; | |
368 | +; When the assembler has been implemented, this should | |
369 | +; set the ASSEMBLER vocabulary CURRENT. | |
370 | +; | |
371 | +; Note that ;CODE, unlike DOES>, is IMMEDIATE, and compiles | |
372 | +; (;CODE), which will do the actual work of changing the LATEST | |
373 | +; definition's characteristic when the defining word runs. | |
374 | +; Assembly is then done by the interpreter rather than the compiler. | |
375 | +; | |
376 | +; Note also that I would be inclined to check the stack here (QSTACK) | |
377 | +; and mark it again, to be checked at the end of the assembly | |
378 | +; language code by a word called ";ASM" or some such. | |
379 | +; The 6800 model, on the other hand, suggests just replacing the | |
380 | +; | |
381 | + HIHEADER ";CODE", SEMIC, DOCOL, MIMM | |
382 | + .data.l QCSP,COMPIL,PSCODE,SMUDGE,LBRAK,QSTACK | |
383 | + .data.l NOOP, NOOP | |
384 | + .data.l SEMIS | |
385 | +; note: "QSTACK" can be replaced by "ASSEMBLER" later, | |
386 | +; or stack-checking performed here and at the end of assembly, too. | |
387 | +; For the present, we can still hand-assemble code and use , and C, | |
388 | +; to "poke" it in after the ;CODE . | |
389 | + | |
390 | + | |
391 | +; <BUILDS ( --- ) | |
392 | +; { : name <BUILDS preparatory-stuff | |
393 | +; DOES> defining-stuff ; } typical use | |
394 | +; Build a header for DOES> definitions. | |
395 | +; The defining code is high-level. | |
396 | +; | |
397 | +; Actually <BUILDS just compiles a CONSTANT zero | |
398 | +; which can be overwritten later by DOES>. | |
399 | +; | |
400 | +; Note that <BUILDS is not IMMEDIATE, | |
401 | +; and therefore executes during a definition's run-time, | |
402 | +; rather than its compile-time. | |
403 | +; It is not intended to be used directly, | |
404 | +; but rather so that one definition can build another. | |
405 | +; Also, note that nothing particularly special | |
406 | +; happens in the defining definition until DOES> executes. | |
407 | +; The name <BUILDS seems intended to be a reminder | |
408 | +; of what is about to occur. | |
409 | +; | |
410 | + HIHEADER "<BUILDS", BUILDS, DOCOL | |
411 | + .data.l ZERO,CON | |
412 | + .data.l SEMIS | |
413 | + | |
414 | + | |
415 | +; DOES> ( --- ) ( IP *** ) C | |
416 | +; Define run-time behavior of definitions at the high level | |
417 | +; -- could be called the FORTH equivalent of a compiler-compiler, | |
418 | +; but not-quite-the-same. | |
419 | +; DOES> assumes that the LATEST symbol table entry has | |
420 | +; at least one word of parameter field, which <BUILDS provides. | |
421 | +; | |
422 | +; Note that DOES> is also not IMMEDIATE. | |
423 | +; When the defining word containing DOES> executes the DOES> icode, | |
424 | +; it overwrites the LATEST symbol's CFA with the DOES> | |
425 | +; (hidden) characteristic (DODOES), | |
426 | +; overwrites the first word of that symbol's parameter field | |
427 | +; with its own IP, and pops the previous IP from the return stack. | |
428 | +; The icodes which follow DOES> in the stream do not execute | |
429 | +; at the defining word's run-time, | |
430 | +; but at the run-time of the word which is being CREATEd. | |
431 | +; | |
432 | +; This is similar to ;CODE, but at the high-level. | |
433 | +; | |
434 | +; The advantage of this kind of behaviour is that the defined word | |
435 | +; can contain both operations and data to be operated on. | |
436 | +; This is how FORTH data objects define their own behavior. | |
437 | +; | |
438 | +; Finally, note that the effective code field for DOES> definitions | |
439 | +; is two natural words, rather than the usual on. This means that | |
440 | +; the effective parameter field is one word farther from the header | |
441 | +; than with ;CODE. | |
442 | +; | |
443 | + HIHEADER "DOES>", DOES, DOCOL | |
444 | + .data.l FROMR,NATPLUS,LATEST,PFA,STORE | |
445 | + .data.l PSCODE | |
446 | +DODOES: | |
447 | +_fDODOES: | |
448 | + mov.l fIP, @-fRP ; ready to resume caller | |
449 | + add #NATURAL_SIZE, fW ; point to characteristic being invoked | |
450 | + mov.l @fW, fIP ; Ready to start high-level characteristic. | |
451 | + add #NATURAL_SIZE, fW ; high-level parameter field | |
452 | + rts ; Back to the inner interpreter | |
453 | + mov.l fW, @-fSP ; push the address as we go | |
454 | + | |
455 | + | |
456 | +; ." ( --- ) P | |
457 | +; { ." something-to-be-printed " } typical input | |
458 | +; Use WORD to parse to trailing quote. | |
459 | +; If compiling, compile XDOTQ and string parsed, | |
460 | +; otherwise, TYPE string. | |
461 | +; | |
462 | +; Maximum length is installation dependent and not well-defined. | |
463 | +; Note that WORD uses unallocated space in the dictionary as a | |
464 | +; convenient parsing buffer, | |
465 | +; so all that is needed after the scan is an allot | |
466 | +; to finish compiling the string into the instruction stream. | |
467 | +; But on the SH-3, we must then ALIGN the dictionary with NULs. | |
468 | +; (I suppose ASCII SPACE might do as well, relative to the high bit.) | |
469 | +; | |
470 | + HIHEADER ".""", DOTQ, DOCOL, MIMM | |
471 | + .data.l LIT | |
472 | + .data.l """" | |
473 | + .data.l STATE,AT,ZBRAN | |
474 | + mTARGET DOTQinterp | |
475 | + .data.l COMPIL,PDOTQ,WORD | |
476 | + .data.l HERE,CAT,ONEP,ALLOT,NULCOMMA | |
477 | + .data.l BRAN | |
478 | + mTARGET DOTQleave | |
479 | +DOTQinterp: | |
480 | + .data.l WORD,HERE,COUNT,TYPE | |
481 | +DOTQleave: | |
482 | + .data.l SEMIS | |
483 | + | |
484 | + | |
485 | +; ?STACK ( --- ) | |
486 | +; Check paramater stack and ERROR if out of bounds. | |
487 | +; | |
488 | +; Checks that the stack hasn't entered the buffer region. | |
489 | +; | |
490 | + HIHEADER "?STACK", QSTACK, DOCOL | |
491 | + .data.l LIT | |
492 | + .data.l SINIT-ORIG ; Why not the USER S0? | |
493 | + .data.l PORIG,AT,PTRWIDTH,SUB,SPAT,LESS,LIT | |
494 | + .data.l errSTACK_UNDERFLOW | |
495 | + .data.l QERR ; stack underflow? | |
496 | +; | |
497 | + .data.l SPAT | |
498 | + .data.l HERE,LIT | |
499 | + .data.l h'80 ; hard-wired buffer zone of 128 | |
500 | + .data.l PLUS,LESS,ZBRAN | |
501 | + .data.l QSTACleave | |
502 | + .data.l LIT | |
503 | + .data.l errDICTIONARY_FULL ; at least 128 higher than dictionary pointer? | |
504 | + .data.l QERR ; stack overflow? | |
505 | +QSTACleave: | |
506 | + .data.l SEMIS | |
507 | + | |
321 | 508 | |
322 | 509 | ; [COMPILE] ( --- ) P |
323 | 510 | ; { [COMPILE] name } typical use |
@@ -42,7 +42,8 @@ | ||
42 | 42 | errNONE: .equ 0 |
43 | 43 | ; FCC "DATA STACK UNDERFLOW " 1 |
44 | 44 | errSTACK_UNDERFLOW: .equ 1 |
45 | -; FCC "DICTIONARY FULL " 2 | |
45 | +; FCC "DICTIONARY FULL " 2 | |
46 | +errDICTIONARY_FULL: .equ 2 | |
46 | 47 | ; FCC "ADDRESS RESOLUTION ERROR " 3 |
47 | 48 | ; FCC "HIDES DEFINITION IN " 4 |
48 | 49 | ; FCC "NULL VECTOR WRITTEN " 5 |
@@ -764,6 +764,35 @@ DDUPzero: | ||
764 | 764 | .data.l SEMIS |
765 | 765 | |
766 | 766 | |
767 | +; COUNT ( strptr --- strptr+1 count ) | |
768 | +; Convert counted string to string and count. (Fetch the byte at | |
769 | +; strptr, post-increment and leave the pointer under the count.) | |
770 | +; COUNT is typically used to set up the arguments for TYPE. | |
771 | +; | |
772 | + HIHEADER COUNT, COUNT, DOCOL | |
773 | + .data.l DUP,ONEP,SWAP,CAT | |
774 | + .data.l SEMIS | |
775 | + | |
776 | + | |
777 | +; -TRAILING ( strptr count1 --- strptr count2 ) | |
778 | +; Supress trailing blanks. | |
779 | +; (Subtract count of trailing blanks from count1.) | |
780 | +; | |
781 | + HIHEADER "-TRAILING", DTRAIL, DOCOL | |
782 | + .data.l DUP,ZERO,XDO | |
783 | +DTRALloop: | |
784 | + .data.l OVER,OVER,PLUS,ONE,SUB,CAT,BL | |
785 | + .data.l SUB,ZBRAN | |
786 | + mTARGET DTRALbackup | |
787 | + .data.l LEAVE,BRAN | |
788 | + mTARGET DTRALend | |
789 | +DTRALbackup: | |
790 | + .data.l ONE,SUB | |
791 | +DTRALend: | |
792 | + .data.l XLOOP | |
793 | + mTARGET DTRALloop | |
794 | + .data.l SEMIS | |
795 | + | |
767 | 796 | |
768 | 797 | |
769 | 798 | ; D- ( d1 d2 --- d1+d2 ) |
@@ -233,3 +233,32 @@ | ||
233 | 233 | .data.l QERR |
234 | 234 | .data.l SEMIS |
235 | 235 | |
236 | + | |
237 | +; TYPE ( strptr count --- ) | |
238 | +; EMIT count characters at strptr. | |
239 | +; | |
240 | + HIHEADER TYPE, TYPE, DOCOL | |
241 | + .data.l DDUP,ZBRAN | |
242 | + mTARGET TYPEdrop | |
243 | + .data.l OVER,PLUS,SWAP,XDO | |
244 | +TYPEloop: | |
245 | + .data.l I,CAT,EMIT,XLOOP | |
246 | + mTARGET TYPEloop | |
247 | + .data.l BRAN | |
248 | + mTARGET TYPEleave | |
249 | +TYPEdrop: | |
250 | + .data.l DROP | |
251 | +TYPEleave: | |
252 | + .data.l SEMIS | |
253 | + | |
254 | + | |
255 | +; (.") ( --- ) | |
256 | +; TYPE counted string out of instruction stream (updating IP). | |
257 | +; | |
258 | + HIHEADER "(."")", PDOTQ, DOCOL | |
259 | + .data.l R,COUNT,DUP,ONEP | |
260 | + .data.l FROMR,PLUS,ALIGN,TOR,TYPE | |
261 | + .data.l SEMIS | |
262 | + | |
263 | + | |
264 | + |
@@ -297,7 +297,7 @@ TRAVloop: | ||
297 | 297 | .data.l _fPFA-_lPFA ; Use the offsets in its own header. |
298 | 298 | .data.l PLUS |
299 | 299 | .data.l SEMIS |
300 | - | |
300 | + | |
301 | 301 | |
302 | 302 | ; HEADER , |
303 | 303 | ; HIHEADER , , |
@@ -50,15 +50,18 @@ | ||
50 | 50 | ; CONTXT: .define "NOOP" ; used in COLON |
51 | 51 | CREATE: .define "NOOP" ; used in COLON |
52 | 52 | ; RBRAK: .define "NOOP" ; used in COLON |
53 | -PSCODE: .define "NOOP" ; used in COLON | |
53 | +; PSCODE: .define "NOOP" ; used in COLON | |
54 | 54 | ; QCSP: .define "NOOP" ; used in SEMI |
55 | 55 | ; COMPIL: .define "NOOP" ; used in SEMI |
56 | 56 | ; SMUDGE: .define "NOOP" ; used in SEMI |
57 | 57 | ; LBRAK: .define "NOOP" ; used in SEMI |
58 | 58 | ; COMMA: .define "NOOP" ; used in CONSTANT |
59 | -DODOES: .define "NOOP" ; used in ROMFORTH | |
59 | +; DODOES: .define "NOOP" ; used in ROMFORTH | |
60 | 60 | DOVOC: .define "NOOP" ; used in ROMFORTH |
61 | 61 | ERROR: .define "NOOP" ; used in QERROR |
62 | +; QSTACK: .define "NOOP" ; used in ;CODE | |
63 | +WORD: .define "NOOP" ; used in DOTQ | |
64 | + | |
62 | 65 | ; : .define "NOOP" |
63 | 66 | |
64 | 67 |