xref: /illumos-gate/usr/src/common/ficl/vm.c (revision bde334a8dbd66dfa70ce4d7fc9dcad6e1ae45fe4)
1 /*
2  * v m . c
3  * Forth Inspired Command Language - virtual machine methods
4  * Author: John Sadler (john_sadler@alum.mit.edu)
5  * Created: 19 July 1997
6  * $Id: vm.c,v 1.17 2010/09/13 18:43:04 asau Exp $
7  */
8 /*
9  * This file implements the virtual machine of Ficl. Each virtual
10  * machine retains the state of an interpreter. A virtual machine
11  * owns a pair of stacks for parameters and return addresses, as
12  * well as a pile of state variables and the two dedicated registers
13  * of the interpreter.
14  */
15 /*
16  * Copyright (c) 1997-2001 John Sadler (john_sadler@alum.mit.edu)
17  * All rights reserved.
18  *
19  * Get the latest Ficl release at http://ficl.sourceforge.net
20  *
21  * I am interested in hearing from anyone who uses Ficl. If you have
22  * a problem, a success story, a defect, an enhancement request, or
23  * if you would like to contribute to the Ficl release, please
24  * contact me by email at the address above.
25  *
26  * L I C E N S E  and  D I S C L A I M E R
27  *
28  * Redistribution and use in source and binary forms, with or without
29  * modification, are permitted provided that the following conditions
30  * are met:
31  * 1. Redistributions of source code must retain the above copyright
32  *    notice, this list of conditions and the following disclaimer.
33  * 2. Redistributions in binary form must reproduce the above copyright
34  *    notice, this list of conditions and the following disclaimer in the
35  *    documentation and/or other materials provided with the distribution.
36  *
37  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
38  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
39  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
40  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
41  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
42  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
43  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
45  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
46  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
47  * SUCH DAMAGE.
48  */
49 
50 #include "ficl.h"
51 
52 #if FICL_ROBUST >= 2
53 #define	FICL_VM_CHECK(vm)	\
54 	FICL_VM_ASSERT(vm, (*(vm->ip - 1)) == vm->runningWord)
55 #else
56 #define	FICL_VM_CHECK(vm)
57 #endif
58 
59 /*
60  * v m B r a n c h R e l a t i v e
61  */
62 void
63 ficlVmBranchRelative(ficlVm *vm, int offset)
64 {
65 	vm->ip += offset;
66 }
67 
68 /*
69  * v m C r e a t e
70  * Creates a virtual machine either from scratch (if vm is NULL on entry)
71  * or by resizing and reinitializing an existing VM to the specified stack
72  * sizes.
73  */
74 ficlVm *
75 ficlVmCreate(ficlVm *vm, unsigned nPStack, unsigned nRStack)
76 {
77 	if (vm == NULL) {
78 		vm = (ficlVm *)ficlMalloc(sizeof (ficlVm));
79 		FICL_ASSERT(NULL, vm);
80 		memset(vm, 0, sizeof (ficlVm));
81 	}
82 
83 	if (vm->dataStack)
84 		ficlStackDestroy(vm->dataStack);
85 	vm->dataStack = ficlStackCreate(vm, "data", nPStack);
86 
87 	if (vm->returnStack)
88 		ficlStackDestroy(vm->returnStack);
89 	vm->returnStack = ficlStackCreate(vm, "return", nRStack);
90 
91 #if FICL_WANT_FLOAT
92 	if (vm->floatStack)
93 		ficlStackDestroy(vm->floatStack);
94 	vm->floatStack = ficlStackCreate(vm, "float", nPStack);
95 #endif
96 
97 	ficlVmReset(vm);
98 	return (vm);
99 }
100 
101 /*
102  * v m D e l e t e
103  * Free all memory allocated to the specified VM and its subordinate
104  * structures.
105  */
106 void
107 ficlVmDestroy(ficlVm *vm)
108 {
109 	if (vm) {
110 		ficlFree(vm->dataStack);
111 		ficlFree(vm->returnStack);
112 #if FICL_WANT_FLOAT
113 		ficlFree(vm->floatStack);
114 #endif
115 		ficlFree(vm);
116 	}
117 }
118 
119 /*
120  * v m E x e c u t e
121  * Sets up the specified word to be run by the inner interpreter.
122  * Executes the word's code part immediately, but in the case of
123  * colon definition, the definition itself needs the inner interpreter
124  * to complete. This does not happen until control reaches ficlExec
125  */
126 void
127 ficlVmExecuteWord(ficlVm *vm, ficlWord *pWord)
128 {
129 	ficlVmInnerLoop(vm, pWord);
130 }
131 
132 static void
133 ficlVmOptimizeJumpToJump(ficlVm *vm, ficlIp ip)
134 {
135 	ficlIp destination;
136 	switch ((ficlInstruction)(*ip)) {
137 	case ficlInstructionBranchParenWithCheck:
138 		*ip = (ficlWord *)ficlInstructionBranchParen;
139 		goto RUNTIME_FIXUP;
140 
141 	case ficlInstructionBranch0ParenWithCheck:
142 		*ip = (ficlWord *)ficlInstructionBranch0Paren;
143 RUNTIME_FIXUP:
144 		ip++;
145 		destination = ip + *(ficlInteger *)ip;
146 		switch ((ficlInstruction)*destination) {
147 		case ficlInstructionBranchParenWithCheck:
148 			/* preoptimize where we're jumping to */
149 			ficlVmOptimizeJumpToJump(vm, destination);
150 			/* FALLTHROUGH */
151 		case ficlInstructionBranchParen:
152 			destination++;
153 			destination += *(ficlInteger *)destination;
154 			*ip = (ficlWord *)(destination - ip);
155 		break;
156 		}
157 	}
158 }
159 
160 /*
161  * v m I n n e r L o o p
162  * the mysterious inner interpreter...
163  * This loop is the address interpreter that makes colon definitions
164  * work. Upon entry, it assumes that the IP points to an entry in
165  * a definition (the body of a colon word). It runs one word at a time
166  * until something does vmThrow. The catcher for this is expected to exist
167  * in the calling code.
168  * vmThrow gets you out of this loop with a longjmp()
169  */
170 
171 #if FICL_ROBUST <= 1
172 	/* turn off stack checking for primitives */
173 #define	_CHECK_STACK(stack, top, pop, push)
174 #else
175 
176 #define	_CHECK_STACK(stack, top, pop, push)	\
177 	ficlStackCheckNospill(stack, top, pop, push)
178 
179 static FICL_PLATFORM_INLINE void
180 ficlStackCheckNospill(ficlStack *stack, ficlCell *top, int popCells,
181     int pushCells)
182 {
183 	/*
184 	 * Why save and restore stack->top?
185 	 * So the simple act of stack checking doesn't force a "register" spill,
186 	 * which might mask bugs (places where we needed to spill but didn't).
187 	 * --lch
188 	 */
189 	ficlCell *oldTop = stack->top;
190 	stack->top = top;
191 	ficlStackCheck(stack, popCells, pushCells);
192 	stack->top = oldTop;
193 }
194 
195 #endif /* FICL_ROBUST <= 1 */
196 
197 #define	CHECK_STACK(pop, push)		\
198 	_CHECK_STACK(vm->dataStack, dataTop, pop, push)
199 #define	CHECK_FLOAT_STACK(pop, push)	\
200 	_CHECK_STACK(vm->floatStack, floatTop, pop, push)
201 #define	CHECK_RETURN_STACK(pop, push)	\
202 	_CHECK_STACK(vm->returnStack, returnTop, pop, push)
203 
204 #if FICL_WANT_FLOAT
205 #define	FLOAT_LOCAL_VARIABLE_SPILL	\
206 	vm->floatStack->top = floatTop;
207 #define	FLOAT_LOCAL_VARIABLE_REFILL	\
208 	floatTop = vm->floatStack->top;
209 #else
210 #define	FLOAT_LOCAL_VARIABLE_SPILL
211 #define	FLOAT_LOCAL_VARIABLE_REFILL
212 #endif  /* FICL_WANT_FLOAT */
213 
214 #if FICL_WANT_LOCALS
215 #define	LOCALS_LOCAL_VARIABLE_SPILL	\
216 	vm->returnStack->frame = frame;
217 #define	LOCALS_LOCAL_VARIABLE_REFILL \
218 	frame = vm->returnStack->frame;
219 #else
220 #define	LOCALS_LOCAL_VARIABLE_SPILL
221 #define	LOCALS_LOCAL_VARIABLE_REFILL
222 #endif  /* FICL_WANT_FLOAT */
223 
224 #define	LOCAL_VARIABLE_SPILL	\
225 		vm->ip = (ficlIp)ip;	\
226 		vm->dataStack->top = dataTop;	\
227 		vm->returnStack->top = returnTop;	\
228 		FLOAT_LOCAL_VARIABLE_SPILL \
229 		LOCALS_LOCAL_VARIABLE_SPILL
230 
231 #define	LOCAL_VARIABLE_REFILL	\
232 		ip = (ficlInstruction *)vm->ip; \
233 		dataTop = vm->dataStack->top;	\
234 		returnTop = vm->returnStack->top;	\
235 		FLOAT_LOCAL_VARIABLE_REFILL	\
236 		LOCALS_LOCAL_VARIABLE_REFILL
237 
238 void
239 ficlVmInnerLoop(ficlVm *vm, ficlWord *fw)
240 {
241 	register ficlInstruction *ip;
242 	register ficlCell *dataTop;
243 	register ficlCell *returnTop;
244 #if FICL_WANT_FLOAT
245 	register ficlCell *floatTop;
246 	ficlFloat f;
247 #endif  /* FICL_WANT_FLOAT */
248 #if FICL_WANT_LOCALS
249 	register ficlCell *frame;
250 #endif  /* FICL_WANT_LOCALS */
251 	jmp_buf *oldExceptionHandler;
252 	jmp_buf exceptionHandler;
253 	int except;
254 	int once;
255 	volatile int count;	/* volatile because of longjmp */
256 	ficlInstruction instruction;
257 	ficlInteger i;
258 	ficlUnsigned u;
259 	ficlCell c;
260 	ficlCountedString *s;
261 	ficlCell *cell;
262 	char *cp;
263 
264 	once = (fw != NULL);
265 	if (once)
266 		count = 1;
267 
268 	oldExceptionHandler = vm->exceptionHandler;
269 	/* This has to come before the setjmp! */
270 	vm->exceptionHandler = &exceptionHandler;
271 	except = setjmp(exceptionHandler);
272 
273 	LOCAL_VARIABLE_REFILL;
274 
275 	if (except) {
276 		LOCAL_VARIABLE_SPILL;
277 		vm->exceptionHandler = oldExceptionHandler;
278 		ficlVmThrow(vm, except);
279 	}
280 
281 	for (;;) {
282 		if (once) {
283 			if (!count--)
284 				break;
285 			instruction = (ficlInstruction)((void *)fw);
286 		} else {
287 			instruction = *ip++;
288 			fw = (ficlWord *)instruction;
289 		}
290 
291 AGAIN:
292 		switch (instruction) {
293 		case ficlInstructionInvalid:
294 			ficlVmThrowError(vm,
295 			    "Error: NULL instruction executed!");
296 			break;
297 
298 		case ficlInstruction1:
299 		case ficlInstruction2:
300 		case ficlInstruction3:
301 		case ficlInstruction4:
302 		case ficlInstruction5:
303 		case ficlInstruction6:
304 		case ficlInstruction7:
305 		case ficlInstruction8:
306 		case ficlInstruction9:
307 		case ficlInstruction10:
308 		case ficlInstruction11:
309 		case ficlInstruction12:
310 		case ficlInstruction13:
311 		case ficlInstruction14:
312 		case ficlInstruction15:
313 		case ficlInstruction16:
314 			CHECK_STACK(0, 1);
315 			(++dataTop)->i = instruction;
316 			continue;
317 
318 		case ficlInstruction0:
319 		case ficlInstructionNeg1:
320 		case ficlInstructionNeg2:
321 		case ficlInstructionNeg3:
322 		case ficlInstructionNeg4:
323 		case ficlInstructionNeg5:
324 		case ficlInstructionNeg6:
325 		case ficlInstructionNeg7:
326 		case ficlInstructionNeg8:
327 		case ficlInstructionNeg9:
328 		case ficlInstructionNeg10:
329 		case ficlInstructionNeg11:
330 		case ficlInstructionNeg12:
331 		case ficlInstructionNeg13:
332 		case ficlInstructionNeg14:
333 		case ficlInstructionNeg15:
334 		case ficlInstructionNeg16:
335 			CHECK_STACK(0, 1);
336 			(++dataTop)->i = ficlInstruction0 - instruction;
337 			continue;
338 
339 		/*
340 		 * stringlit: Fetch the count from the dictionary, then push
341 		 * the address and count on the stack. Finally, update ip to
342 		 * point to the first aligned address after the string text.
343 		 */
344 		case ficlInstructionStringLiteralParen: {
345 			ficlUnsigned8 length;
346 			CHECK_STACK(0, 2);
347 
348 			s = (ficlCountedString *)(ip);
349 			length = s->length;
350 			cp = s->text;
351 			(++dataTop)->p = cp;
352 			(++dataTop)->i = length;
353 
354 			cp += length + 1;
355 			cp = ficlAlignPointer(cp);
356 			ip = (void *)cp;
357 			continue;
358 		}
359 
360 		case ficlInstructionCStringLiteralParen:
361 			CHECK_STACK(0, 1);
362 
363 			s = (ficlCountedString *)(ip);
364 			cp = s->text + s->length + 1;
365 			cp = ficlAlignPointer(cp);
366 			ip = (void *)cp;
367 			(++dataTop)->p = s;
368 			continue;
369 
370 #if FICL_WANT_OPTIMIZE == FICL_OPTIMIZE_FOR_SIZE
371 #if FICL_WANT_FLOAT
372 FLOAT_PUSH_CELL_POINTER_DOUBLE_MINIPROC:
373 			*++floatTop = cell[1];
374 			/* intentional fall-through */
375 FLOAT_PUSH_CELL_POINTER_MINIPROC:
376 			*++floatTop = cell[0];
377 			continue;
378 
379 FLOAT_POP_CELL_POINTER_MINIPROC:
380 			cell[0] = *floatTop--;
381 			continue;
382 
383 FLOAT_POP_CELL_POINTER_DOUBLE_MINIPROC:
384 			cell[0] = *floatTop--;
385 			cell[1] = *floatTop--;
386 			continue;
387 
388 #define	FLOAT_PUSH_CELL_POINTER_DOUBLE(cp)	\
389 	cell = (cp); goto FLOAT_PUSH_CELL_POINTER_DOUBLE_MINIPROC
390 #define	FLOAT_PUSH_CELL_POINTER(cp)		\
391 	cell = (cp); goto FLOAT_PUSH_CELL_POINTER_MINIPROC
392 #define	FLOAT_POP_CELL_POINTER_DOUBLE(cp)	\
393 	cell = (cp); goto FLOAT_POP_CELL_POINTER_DOUBLE_MINIPROC
394 #define	FLOAT_POP_CELL_POINTER(cp)		\
395 	cell = (cp); goto FLOAT_POP_CELL_POINTER_MINIPROC
396 #endif /* FICL_WANT_FLOAT */
397 
398 		/*
399 		 * Think of these as little mini-procedures.
400 		 * --lch
401 		 */
402 PUSH_CELL_POINTER_DOUBLE_MINIPROC:
403 			*++dataTop = cell[1];
404 			/* intentional fall-through */
405 PUSH_CELL_POINTER_MINIPROC:
406 			*++dataTop = cell[0];
407 			continue;
408 
409 POP_CELL_POINTER_MINIPROC:
410 			cell[0] = *dataTop--;
411 			continue;
412 POP_CELL_POINTER_DOUBLE_MINIPROC:
413 			cell[0] = *dataTop--;
414 			cell[1] = *dataTop--;
415 			continue;
416 
417 #define	PUSH_CELL_POINTER_DOUBLE(cp)	\
418 	cell = (cp); goto PUSH_CELL_POINTER_DOUBLE_MINIPROC
419 #define	PUSH_CELL_POINTER(cp)		\
420 	cell = (cp); goto PUSH_CELL_POINTER_MINIPROC
421 #define	POP_CELL_POINTER_DOUBLE(cp)	\
422 	cell = (cp); goto POP_CELL_POINTER_DOUBLE_MINIPROC
423 #define	POP_CELL_POINTER(cp)		\
424 	cell = (cp); goto POP_CELL_POINTER_MINIPROC
425 
426 BRANCH_MINIPROC:
427 			ip += *(ficlInteger *)ip;
428 			continue;
429 
430 #define	BRANCH()	goto BRANCH_MINIPROC
431 
432 EXIT_FUNCTION_MINIPROC:
433 			ip = (ficlInstruction *)((returnTop--)->p);
434 			continue;
435 
436 #define	EXIT_FUNCTION	goto EXIT_FUNCTION_MINIPROC
437 
438 #else /* FICL_WANT_SIZE */
439 
440 #if FICL_WANT_FLOAT
441 #define	FLOAT_PUSH_CELL_POINTER_DOUBLE(cp)	\
442 	cell = (cp); *++floatTop = cell[1]; *++floatTop = *cell; continue
443 #define	FLOAT_PUSH_CELL_POINTER(cp)		\
444 	cell = (cp); *++floatTop = *cell; continue
445 #define	FLOAT_POP_CELL_POINTER_DOUBLE(cp)	\
446 	cell = (cp); *cell = *floatTop--; cell[1] = *floatTop--; continue
447 #define	FLOAT_POP_CELL_POINTER(cp)		\
448 	cell = (cp); *cell = *floatTop--; continue
449 #endif /* FICL_WANT_FLOAT */
450 
451 #define	PUSH_CELL_POINTER_DOUBLE(cp)	\
452 	cell = (cp); *++dataTop = cell[1]; *++dataTop = *cell; continue
453 #define	PUSH_CELL_POINTER(cp)		\
454 	cell = (cp); *++dataTop = *cell; continue
455 #define	POP_CELL_POINTER_DOUBLE(cp)	\
456 	cell = (cp); *cell = *dataTop--; cell[1] = *dataTop--; continue
457 #define	POP_CELL_POINTER(cp)		\
458 	cell = (cp); *cell = *dataTop--; continue
459 
460 #define	BRANCH()	ip += *(ficlInteger *)ip; continue
461 #define	EXIT_FUNCTION()	ip = (ficlInstruction *)((returnTop--)->p); continue
462 
463 #endif /* FICL_WANT_SIZE */
464 
465 
466 		/*
467 		 * This is the runtime for (literal). It assumes that it is
468 		 * part of a colon definition, and that the next ficlCell
469 		 * contains a value to be pushed on the parameter stack at
470 		 * runtime. This code is compiled by "literal".
471 		 */
472 
473 		case ficlInstructionLiteralParen:
474 			CHECK_STACK(0, 1);
475 			(++dataTop)->i = *ip++;
476 			continue;
477 
478 		case ficlInstruction2LiteralParen:
479 			CHECK_STACK(0, 2);
480 			(++dataTop)->i = ip[1];
481 			(++dataTop)->i = ip[0];
482 			ip += 2;
483 			continue;
484 
485 #if FICL_WANT_LOCALS
486 		/*
487 		 * Link a frame on the return stack, reserving nCells of space
488 		 * for locals - the value of nCells is the next ficlCell in
489 		 * the instruction stream.
490 		 * 1) Push frame onto returnTop
491 		 * 2) frame = returnTop
492 		 * 3) returnTop += nCells
493 		 */
494 		case ficlInstructionLinkParen: {
495 			ficlInteger nCells = *ip++;
496 			(++returnTop)->p = frame;
497 			frame = returnTop + 1;
498 			returnTop += nCells;
499 			continue;
500 		}
501 
502 		/*
503 		 * Unink a stack frame previously created by stackLink
504 		 * 1) dataTop = frame
505 		 * 2) frame = pop()
506 		 */
507 		case ficlInstructionUnlinkParen:
508 			returnTop = frame - 1;
509 			frame = (returnTop--)->p;
510 			continue;
511 
512 		/*
513 		 * Immediate - cfa of a local while compiling - when executed,
514 		 * compiles code to fetch the value of a local given the
515 		 * local's index in the word's pfa
516 		 */
517 #if FICL_WANT_FLOAT
518 		case ficlInstructionGetF2LocalParen:
519 			FLOAT_PUSH_CELL_POINTER_DOUBLE(frame + *ip++);
520 
521 		case ficlInstructionGetFLocalParen:
522 			FLOAT_PUSH_CELL_POINTER(frame + *ip++);
523 
524 		case ficlInstructionToF2LocalParen:
525 			FLOAT_POP_CELL_POINTER_DOUBLE(frame + *ip++);
526 
527 		case ficlInstructionToFLocalParen:
528 			FLOAT_POP_CELL_POINTER(frame + *ip++);
529 #endif /* FICL_WANT_FLOAT */
530 
531 		case ficlInstructionGet2LocalParen:
532 			PUSH_CELL_POINTER_DOUBLE(frame + *ip++);
533 
534 		case ficlInstructionGetLocalParen:
535 			PUSH_CELL_POINTER(frame + *ip++);
536 
537 		/*
538 		 * Immediate - cfa of a local while compiling - when executed,
539 		 * compiles code to store the value of a local given the
540 		 * local's index in the word's pfa
541 		 */
542 
543 		case ficlInstructionTo2LocalParen:
544 			POP_CELL_POINTER_DOUBLE(frame + *ip++);
545 
546 		case ficlInstructionToLocalParen:
547 			POP_CELL_POINTER(frame + *ip++);
548 
549 		/*
550 		 * Silly little minor optimizations.
551 		 * --lch
552 		 */
553 		case ficlInstructionGetLocal0:
554 			PUSH_CELL_POINTER(frame);
555 
556 		case ficlInstructionGetLocal1:
557 			PUSH_CELL_POINTER(frame + 1);
558 
559 		case ficlInstructionGet2Local0:
560 			PUSH_CELL_POINTER_DOUBLE(frame);
561 
562 		case ficlInstructionToLocal0:
563 			POP_CELL_POINTER(frame);
564 
565 		case ficlInstructionToLocal1:
566 			POP_CELL_POINTER(frame + 1);
567 
568 		case ficlInstructionTo2Local0:
569 			POP_CELL_POINTER_DOUBLE(frame);
570 
571 #endif /* FICL_WANT_LOCALS */
572 
573 		case ficlInstructionPlus:
574 			CHECK_STACK(2, 1);
575 			i = (dataTop--)->i;
576 			dataTop->i += i;
577 			continue;
578 
579 		case ficlInstructionMinus:
580 			CHECK_STACK(2, 1);
581 			i = (dataTop--)->i;
582 			dataTop->i -= i;
583 			continue;
584 
585 		case ficlInstruction1Plus:
586 			CHECK_STACK(1, 1);
587 			dataTop->i++;
588 			continue;
589 
590 		case ficlInstruction1Minus:
591 			CHECK_STACK(1, 1);
592 			dataTop->i--;
593 			continue;
594 
595 		case ficlInstruction2Plus:
596 			CHECK_STACK(1, 1);
597 			dataTop->i += 2;
598 			continue;
599 
600 		case ficlInstruction2Minus:
601 			CHECK_STACK(1, 1);
602 			dataTop->i -= 2;
603 			continue;
604 
605 		case ficlInstructionDup: {
606 			ficlInteger i = dataTop->i;
607 			CHECK_STACK(0, 1);
608 			(++dataTop)->i = i;
609 			continue;
610 		}
611 
612 		case ficlInstructionQuestionDup:
613 			CHECK_STACK(1, 2);
614 
615 			if (dataTop->i != 0) {
616 				dataTop[1] = dataTop[0];
617 				dataTop++;
618 			}
619 
620 			continue;
621 
622 		case ficlInstructionSwap: {
623 			ficlCell swap;
624 			CHECK_STACK(2, 2);
625 			swap = dataTop[0];
626 			dataTop[0] = dataTop[-1];
627 			dataTop[-1] = swap;
628 			continue;
629 		}
630 
631 		case ficlInstructionDrop:
632 			CHECK_STACK(1, 0);
633 			dataTop--;
634 			continue;
635 
636 		case ficlInstruction2Drop:
637 			CHECK_STACK(2, 0);
638 			dataTop -= 2;
639 			continue;
640 
641 		case ficlInstruction2Dup:
642 			CHECK_STACK(2, 4);
643 			dataTop[1] = dataTop[-1];
644 			dataTop[2] = *dataTop;
645 			dataTop += 2;
646 			continue;
647 
648 		case ficlInstructionOver:
649 			CHECK_STACK(2, 3);
650 			dataTop[1] = dataTop[-1];
651 			dataTop++;
652 			continue;
653 
654 		case ficlInstruction2Over:
655 			CHECK_STACK(4, 6);
656 			dataTop[1] = dataTop[-3];
657 			dataTop[2] = dataTop[-2];
658 			dataTop += 2;
659 			continue;
660 
661 		case ficlInstructionPick:
662 			CHECK_STACK(1, 0);
663 			i = dataTop->i;
664 			if (i < 0)
665 				continue;
666 			CHECK_STACK(i + 2, i + 3);
667 			*dataTop = dataTop[-i - 1];
668 			continue;
669 
670 		/*
671 		 * Do stack rot.
672 		 * rot ( 1 2 3  -- 2 3 1 )
673 		 */
674 		case ficlInstructionRot:
675 			i = 2;
676 			goto ROLL;
677 
678 		/*
679 		 * Do stack roll.
680 		 * roll ( n -- )
681 		 */
682 		case ficlInstructionRoll:
683 			CHECK_STACK(1, 0);
684 			i = (dataTop--)->i;
685 
686 			if (i < 1)
687 				continue;
688 
689 ROLL:
690 			CHECK_STACK(i+1, i+2);
691 			c = dataTop[-i];
692 			memmove(dataTop - i, dataTop - (i - 1),
693 			    i * sizeof (ficlCell));
694 			*dataTop = c;
695 			continue;
696 
697 		/*
698 		 * Do stack -rot.
699 		 * -rot ( 1 2 3  -- 3 1 2 )
700 		 */
701 		case ficlInstructionMinusRot:
702 			i = 2;
703 			goto MINUSROLL;
704 
705 		/*
706 		 * Do stack -roll.
707 		 * -roll ( n -- )
708 		 */
709 		case ficlInstructionMinusRoll:
710 			CHECK_STACK(1, 0);
711 			i = (dataTop--)->i;
712 
713 			if (i < 1)
714 				continue;
715 
716 MINUSROLL:
717 			CHECK_STACK(i+1, i+2);
718 			c = *dataTop;
719 			memmove(dataTop - (i - 1), dataTop - i,
720 			    i * sizeof (ficlCell));
721 			dataTop[-i] = c;
722 
723 			continue;
724 
725 		/*
726 		 * Do stack 2swap
727 		 * 2swap ( 1 2 3 4  -- 3 4 1 2 )
728 		 */
729 		case ficlInstruction2Swap: {
730 			ficlCell c2;
731 			CHECK_STACK(4, 4);
732 
733 			c = *dataTop;
734 			c2 = dataTop[-1];
735 
736 			*dataTop = dataTop[-2];
737 			dataTop[-1] = dataTop[-3];
738 
739 			dataTop[-2] = c;
740 			dataTop[-3] = c2;
741 			continue;
742 		}
743 
744 		case ficlInstructionPlusStore: {
745 			ficlCell *cell;
746 			CHECK_STACK(2, 0);
747 			cell = (ficlCell *)(dataTop--)->p;
748 			cell->i += (dataTop--)->i;
749 			continue;
750 		}
751 
752 		case ficlInstructionQuadFetch: {
753 			ficlUnsigned32 *integer32;
754 			CHECK_STACK(1, 1);
755 			integer32 = (ficlUnsigned32 *)dataTop->i;
756 			dataTop->u = (ficlUnsigned)*integer32;
757 			continue;
758 		}
759 
760 		case ficlInstructionQuadStore: {
761 			ficlUnsigned32 *integer32;
762 			CHECK_STACK(2, 0);
763 			integer32 = (ficlUnsigned32 *)(dataTop--)->p;
764 			*integer32 = (ficlUnsigned32)((dataTop--)->u);
765 			continue;
766 		}
767 
768 		case ficlInstructionWFetch: {
769 			ficlUnsigned16 *integer16;
770 			CHECK_STACK(1, 1);
771 			integer16 = (ficlUnsigned16 *)dataTop->p;
772 			dataTop->u = ((ficlUnsigned)*integer16);
773 			continue;
774 		}
775 
776 		case ficlInstructionWStore: {
777 			ficlUnsigned16 *integer16;
778 			CHECK_STACK(2, 0);
779 			integer16 = (ficlUnsigned16 *)(dataTop--)->p;
780 			*integer16 = (ficlUnsigned16)((dataTop--)->u);
781 			continue;
782 		}
783 
784 		case ficlInstructionCFetch: {
785 			ficlUnsigned8 *integer8;
786 			CHECK_STACK(1, 1);
787 			integer8 = (ficlUnsigned8 *)dataTop->p;
788 			dataTop->u = ((ficlUnsigned)*integer8);
789 			continue;
790 		}
791 
792 		case ficlInstructionCStore: {
793 			ficlUnsigned8 *integer8;
794 			CHECK_STACK(2, 0);
795 			integer8 = (ficlUnsigned8 *)(dataTop--)->p;
796 			*integer8 = (ficlUnsigned8)((dataTop--)->u);
797 			continue;
798 		}
799 
800 
801 		/*
802 		 * l o g i c   a n d   c o m p a r i s o n s
803 		 */
804 
805 		case ficlInstruction0Equals:
806 			CHECK_STACK(1, 1);
807 			dataTop->i = FICL_BOOL(dataTop->i == 0);
808 			continue;
809 
810 		case ficlInstruction0Less:
811 			CHECK_STACK(1, 1);
812 			dataTop->i = FICL_BOOL(dataTop->i < 0);
813 			continue;
814 
815 		case ficlInstruction0Greater:
816 			CHECK_STACK(1, 1);
817 			dataTop->i = FICL_BOOL(dataTop->i > 0);
818 			continue;
819 
820 		case ficlInstructionEquals:
821 			CHECK_STACK(2, 1);
822 			i = (dataTop--)->i;
823 			dataTop->i = FICL_BOOL(dataTop->i == i);
824 			continue;
825 
826 		case ficlInstructionLess:
827 			CHECK_STACK(2, 1);
828 			i = (dataTop--)->i;
829 			dataTop->i = FICL_BOOL(dataTop->i < i);
830 			continue;
831 
832 		case ficlInstructionULess:
833 			CHECK_STACK(2, 1);
834 			u = (dataTop--)->u;
835 			dataTop->i = FICL_BOOL(dataTop->u < u);
836 			continue;
837 
838 		case ficlInstructionAnd:
839 			CHECK_STACK(2, 1);
840 			i = (dataTop--)->i;
841 			dataTop->i = dataTop->i & i;
842 			continue;
843 
844 		case ficlInstructionOr:
845 			CHECK_STACK(2, 1);
846 			i = (dataTop--)->i;
847 			dataTop->i = dataTop->i | i;
848 			continue;
849 
850 		case ficlInstructionXor:
851 			CHECK_STACK(2, 1);
852 			i = (dataTop--)->i;
853 			dataTop->i = dataTop->i ^ i;
854 			continue;
855 
856 		case ficlInstructionInvert:
857 			CHECK_STACK(1, 1);
858 			dataTop->i = ~dataTop->i;
859 			continue;
860 
861 		/*
862 		 * r e t u r n   s t a c k
863 		 */
864 		case ficlInstructionToRStack:
865 			CHECK_STACK(1, 0);
866 			CHECK_RETURN_STACK(0, 1);
867 			*++returnTop = *dataTop--;
868 			continue;
869 
870 		case ficlInstructionFromRStack:
871 			CHECK_STACK(0, 1);
872 			CHECK_RETURN_STACK(1, 0);
873 			*++dataTop = *returnTop--;
874 			continue;
875 
876 		case ficlInstructionFetchRStack:
877 			CHECK_STACK(0, 1);
878 			CHECK_RETURN_STACK(1, 1);
879 			*++dataTop = *returnTop;
880 			continue;
881 
882 		case ficlInstruction2ToR:
883 			CHECK_STACK(2, 0);
884 			CHECK_RETURN_STACK(0, 2);
885 			*++returnTop = dataTop[-1];
886 			*++returnTop = dataTop[0];
887 			dataTop -= 2;
888 			continue;
889 
890 		case ficlInstruction2RFrom:
891 			CHECK_STACK(0, 2);
892 			CHECK_RETURN_STACK(2, 0);
893 			*++dataTop = returnTop[-1];
894 			*++dataTop = returnTop[0];
895 			returnTop -= 2;
896 			continue;
897 
898 		case ficlInstruction2RFetch:
899 			CHECK_STACK(0, 2);
900 			CHECK_RETURN_STACK(2, 2);
901 			*++dataTop = returnTop[-1];
902 			*++dataTop = returnTop[0];
903 			continue;
904 
905 		/*
906 		 * f i l l
907 		 * CORE ( c-addr u char -- )
908 		 * If u is greater than zero, store char in each of u
909 		 * consecutive characters of memory beginning at c-addr.
910 		 */
911 		case ficlInstructionFill: {
912 			char c;
913 			char *memory;
914 			CHECK_STACK(3, 0);
915 			c = (char)(dataTop--)->i;
916 			u = (dataTop--)->u;
917 			memory = (char *)(dataTop--)->p;
918 
919 			/*
920 			 * memset() is faster than the previous hand-rolled
921 			 * solution.  --lch
922 			 */
923 			memset(memory, c, u);
924 			continue;
925 		}
926 
927 		/*
928 		 * l s h i f t
929 		 * l-shift CORE ( x1 u -- x2 )
930 		 * Perform a logical left shift of u bit-places on x1,
931 		 * giving x2. Put zeroes into the least significant bits
932 		 * vacated by the shift. An ambiguous condition exists if
933 		 * u is greater than or equal to the number of bits in a
934 		 * ficlCell.
935 		 *
936 		 * r-shift CORE ( x1 u -- x2 )
937 		 * Perform a logical right shift of u bit-places on x1,
938 		 * giving x2. Put zeroes into the most significant bits
939 		 * vacated by the shift. An ambiguous condition exists
940 		 * if u is greater than or equal to the number of bits
941 		 * in a ficlCell.
942 		 */
943 		case ficlInstructionLShift: {
944 			ficlUnsigned nBits;
945 			ficlUnsigned x1;
946 			CHECK_STACK(2, 1);
947 
948 			nBits = (dataTop--)->u;
949 			x1 = dataTop->u;
950 			dataTop->u = x1 << nBits;
951 			continue;
952 		}
953 
954 		case ficlInstructionRShift: {
955 			ficlUnsigned nBits;
956 			ficlUnsigned x1;
957 			CHECK_STACK(2, 1);
958 
959 			nBits = (dataTop--)->u;
960 			x1 = dataTop->u;
961 			dataTop->u = x1 >> nBits;
962 			continue;
963 		}
964 
965 		/*
966 		 * m a x   &   m i n
967 		 */
968 		case ficlInstructionMax: {
969 			ficlInteger n2;
970 			ficlInteger n1;
971 			CHECK_STACK(2, 1);
972 
973 			n2 = (dataTop--)->i;
974 			n1 = dataTop->i;
975 
976 			dataTop->i = ((n1 > n2) ? n1 : n2);
977 			continue;
978 		}
979 
980 		case ficlInstructionMin: {
981 			ficlInteger n2;
982 			ficlInteger n1;
983 			CHECK_STACK(2, 1);
984 
985 			n2 = (dataTop--)->i;
986 			n1 = dataTop->i;
987 
988 			dataTop->i = ((n1 < n2) ? n1 : n2);
989 			continue;
990 		}
991 
992 		/*
993 		 * m o v e
994 		 * CORE ( addr1 addr2 u -- )
995 		 * If u is greater than zero, copy the contents of u
996 		 * consecutive address units at addr1 to the u consecutive
997 		 * address units at addr2. After MOVE completes, the u
998 		 * consecutive address units at addr2 contain exactly
999 		 * what the u consecutive address units at addr1 contained
1000 		 * before the move.
1001 		 * NOTE! This implementation assumes that a char is the same
1002 		 * size as an address unit.
1003 		 */
1004 		case ficlInstructionMove: {
1005 			ficlUnsigned u;
1006 			char *addr2;
1007 			char *addr1;
1008 			CHECK_STACK(3, 0);
1009 
1010 			u = (dataTop--)->u;
1011 			addr2 = (dataTop--)->p;
1012 			addr1 = (dataTop--)->p;
1013 
1014 			if (u == 0)
1015 				continue;
1016 			/*
1017 			 * Do the copy carefully, so as to be
1018 			 * correct even if the two ranges overlap
1019 			 */
1020 			/* Which ANSI C's memmove() does for you! Yay!  --lch */
1021 			memmove(addr2, addr1, u);
1022 			continue;
1023 		}
1024 
1025 		/*
1026 		 * s t o d
1027 		 * s-to-d CORE ( n -- d )
1028 		 * Convert the number n to the double-ficlCell number d with
1029 		 * the same numerical value.
1030 		 */
1031 		case ficlInstructionSToD: {
1032 			ficlInteger s;
1033 			CHECK_STACK(1, 2);
1034 
1035 			s = dataTop->i;
1036 
1037 			/* sign extend to 64 bits.. */
1038 			(++dataTop)->i = (s < 0) ? -1 : 0;
1039 			continue;
1040 		}
1041 
1042 		/*
1043 		 * c o m p a r e
1044 		 * STRING ( c-addr1 u1 c-addr2 u2 -- n )
1045 		 * Compare the string specified by c-addr1 u1 to the string
1046 		 * specified by c-addr2 u2. The strings are compared, beginning
1047 		 * at the given addresses, character by character, up to the
1048 		 * length of the shorter string or until a difference is found.
1049 		 * If the two strings are identical, n is zero. If the two
1050 		 * strings are identical up to the length of the shorter string,
1051 		 * n is minus-one (-1) if u1 is less than u2 and one (1)
1052 		 * otherwise. If the two strings are not identical up to the
1053 		 * length of the shorter string, n is minus-one (-1) if the
1054 		 * first non-matching character in the string specified by
1055 		 * c-addr1 u1 has a lesser numeric value than the corresponding
1056 		 * character in the string specified by c-addr2 u2 and
1057 		 * one (1) otherwise.
1058 		 */
1059 		case ficlInstructionCompare:
1060 			i = FICL_FALSE;
1061 		goto COMPARE;
1062 
1063 
1064 		case ficlInstructionCompareInsensitive:
1065 			i = FICL_TRUE;
1066 		goto COMPARE;
1067 
1068 COMPARE:
1069 		{
1070 			char *cp1, *cp2;
1071 			ficlUnsigned u1, u2, uMin;
1072 			int n = 0;
1073 
1074 			CHECK_STACK(4, 1);
1075 			u2  = (dataTop--)->u;
1076 			cp2 = (char *)(dataTop--)->p;
1077 			u1  = (dataTop--)->u;
1078 			cp1 = (char *)(dataTop--)->p;
1079 
1080 			uMin = (u1 < u2)? u1 : u2;
1081 			for (; (uMin > 0) && (n == 0); uMin--) {
1082 				int c1 = (unsigned char)*cp1++;
1083 				int c2 = (unsigned char)*cp2++;
1084 
1085 				if (i) {
1086 					c1 = tolower(c1);
1087 					c2 = tolower(c2);
1088 				}
1089 				n = (c1 - c2);
1090 			}
1091 
1092 			if (n == 0)
1093 				n = (int)(u1 - u2);
1094 
1095 			if (n < 0)
1096 				n = -1;
1097 			else if (n > 0)
1098 				n = 1;
1099 
1100 			(++dataTop)->i = n;
1101 			continue;
1102 		}
1103 
1104 		/*
1105 		 * r a n d o m
1106 		 * Ficl-specific
1107 		 */
1108 		case ficlInstructionRandom:
1109 			(++dataTop)->i = random();
1110 		continue;
1111 
1112 		/*
1113 		 * s e e d - r a n d o m
1114 		 * Ficl-specific
1115 		 */
1116 		case ficlInstructionSeedRandom:
1117 			srandom((dataTop--)->i);
1118 		continue;
1119 
1120 		case ficlInstructionGreaterThan: {
1121 			ficlInteger x, y;
1122 			CHECK_STACK(2, 1);
1123 			y = (dataTop--)->i;
1124 			x = dataTop->i;
1125 			dataTop->i = FICL_BOOL(x > y);
1126 			continue;
1127 		}
1128 
1129 		case ficlInstructionUGreaterThan:
1130 			CHECK_STACK(2, 1);
1131 			u = (dataTop--)->u;
1132 			dataTop->i = FICL_BOOL(dataTop->u > u);
1133 			continue;
1134 
1135 		/*
1136 		 * This function simply pops the previous instruction
1137 		 * pointer and returns to the "next" loop. Used for exiting
1138 		 * from within a definition. Note that exitParen is identical
1139 		 * to semiParen - they are in two different functions so that
1140 		 * "see" can correctly identify the end of a colon definition,
1141 		 * even if it uses "exit".
1142 		 */
1143 		case ficlInstructionExitParen:
1144 		case ficlInstructionSemiParen:
1145 			EXIT_FUNCTION();
1146 
1147 		/*
1148 		 * The first time we run "(branch)", perform a "peephole
1149 		 * optimization" to see if we're jumping to another
1150 		 * unconditional jump.  If so, just jump directly there.
1151 		 */
1152 		case ficlInstructionBranchParenWithCheck:
1153 			LOCAL_VARIABLE_SPILL;
1154 			ficlVmOptimizeJumpToJump(vm, vm->ip - 1);
1155 			LOCAL_VARIABLE_REFILL;
1156 		goto BRANCH_PAREN;
1157 
1158 		/*
1159 		 * Same deal with branch0.
1160 		 */
1161 		case ficlInstructionBranch0ParenWithCheck:
1162 			LOCAL_VARIABLE_SPILL;
1163 			ficlVmOptimizeJumpToJump(vm, vm->ip - 1);
1164 			LOCAL_VARIABLE_REFILL;
1165 			/* intentional fall-through */
1166 
1167 		/*
1168 		 * Runtime code for "(branch0)"; pop a flag from the stack,
1169 		 * branch if 0. fall through otherwise.
1170 		 * The heart of "if" and "until".
1171 		 */
1172 		case ficlInstructionBranch0Paren:
1173 			CHECK_STACK(1, 0);
1174 
1175 			if ((dataTop--)->i) {
1176 				/*
1177 				 * don't branch, but skip over branch
1178 				 * relative address
1179 				 */
1180 				ip += 1;
1181 				continue;
1182 			}
1183 			/* otherwise, take branch (to else/endif/begin) */
1184 			/* intentional fall-through! */
1185 
1186 		/*
1187 		 * Runtime for "(branch)" -- expects a literal offset in the
1188 		 * next compilation address, and branches to that location.
1189 		 */
1190 		case ficlInstructionBranchParen:
1191 BRANCH_PAREN:
1192 			BRANCH();
1193 
1194 		case ficlInstructionOfParen: {
1195 			ficlUnsigned a, b;
1196 
1197 			CHECK_STACK(2, 1);
1198 
1199 			a = (dataTop--)->u;
1200 			b = dataTop->u;
1201 
1202 			if (a == b) {
1203 				/* fall through */
1204 				ip++;
1205 				/* remove CASE argument */
1206 				dataTop--;
1207 			} else {
1208 				/* take branch to next of or endcase */
1209 				BRANCH();
1210 			}
1211 
1212 			continue;
1213 		}
1214 
1215 		case ficlInstructionDoParen: {
1216 			ficlCell index, limit;
1217 
1218 			CHECK_STACK(2, 0);
1219 
1220 			index = *dataTop--;
1221 			limit = *dataTop--;
1222 
1223 			/* copy "leave" target addr to stack */
1224 			(++returnTop)->i = *(ip++);
1225 			*++returnTop = limit;
1226 			*++returnTop = index;
1227 
1228 			continue;
1229 		}
1230 
1231 		case ficlInstructionQDoParen: {
1232 			ficlCell index, limit, leave;
1233 
1234 			CHECK_STACK(2, 0);
1235 
1236 			index = *dataTop--;
1237 			limit = *dataTop--;
1238 
1239 			leave.i = *ip;
1240 
1241 			if (limit.u == index.u) {
1242 				ip = leave.p;
1243 			} else {
1244 				ip++;
1245 				*++returnTop = leave;
1246 				*++returnTop = limit;
1247 				*++returnTop = index;
1248 			}
1249 
1250 			continue;
1251 		}
1252 
1253 		case ficlInstructionLoopParen:
1254 		case ficlInstructionPlusLoopParen: {
1255 			ficlInteger index;
1256 			ficlInteger limit;
1257 			int direction = 0;
1258 
1259 			index = returnTop->i;
1260 			limit = returnTop[-1].i;
1261 
1262 			if (instruction == ficlInstructionLoopParen)
1263 				index++;
1264 			else {
1265 				ficlInteger increment;
1266 				CHECK_STACK(1, 0);
1267 				increment = (dataTop--)->i;
1268 				index += increment;
1269 				direction = (increment < 0);
1270 			}
1271 
1272 			if (direction ^ (index >= limit)) {
1273 				/* nuke the loop indices & "leave" addr */
1274 				returnTop -= 3;
1275 				ip++;  /* fall through the loop */
1276 			} else {	/* update index, branch to loop head */
1277 				returnTop->i = index;
1278 				BRANCH();
1279 			}
1280 
1281 			continue;
1282 		}
1283 
1284 
1285 		/*
1286 		 * Runtime code to break out of a do..loop construct
1287 		 * Drop the loop control variables; the branch address
1288 		 * past "loop" is next on the return stack.
1289 		 */
1290 		case ficlInstructionLeave:
1291 			/* almost unloop */
1292 			returnTop -= 2;
1293 			/* exit */
1294 			EXIT_FUNCTION();
1295 
1296 		case ficlInstructionUnloop:
1297 			returnTop -= 3;
1298 			continue;
1299 
1300 		case ficlInstructionI:
1301 			*++dataTop = *returnTop;
1302 			continue;
1303 
1304 		case ficlInstructionJ:
1305 			*++dataTop = returnTop[-3];
1306 			continue;
1307 
1308 		case ficlInstructionK:
1309 			*++dataTop = returnTop[-6];
1310 			continue;
1311 
1312 		case ficlInstructionDoesParen: {
1313 			ficlDictionary *dictionary = ficlVmGetDictionary(vm);
1314 			dictionary->smudge->code =
1315 			    (ficlPrimitive)ficlInstructionDoDoes;
1316 			dictionary->smudge->param[0].p = ip;
1317 			ip = (ficlInstruction *)((returnTop--)->p);
1318 			continue;
1319 		}
1320 
1321 		case ficlInstructionDoDoes: {
1322 			ficlCell *cell;
1323 			ficlIp tempIP;
1324 
1325 			CHECK_STACK(0, 1);
1326 
1327 			cell = fw->param;
1328 			tempIP = (ficlIp)((*cell).p);
1329 			(++dataTop)->p = (cell + 1);
1330 			(++returnTop)->p = (void *)ip;
1331 			ip = (ficlInstruction *)tempIP;
1332 			continue;
1333 		}
1334 
1335 #if FICL_WANT_FLOAT
1336 		case ficlInstructionF2Fetch:
1337 			CHECK_FLOAT_STACK(0, 2);
1338 			CHECK_STACK(1, 0);
1339 			FLOAT_PUSH_CELL_POINTER_DOUBLE((dataTop--)->p);
1340 
1341 		case ficlInstructionFFetch:
1342 			CHECK_FLOAT_STACK(0, 1);
1343 			CHECK_STACK(1, 0);
1344 			FLOAT_PUSH_CELL_POINTER((dataTop--)->p);
1345 
1346 		case ficlInstructionF2Store:
1347 			CHECK_FLOAT_STACK(2, 0);
1348 			CHECK_STACK(1, 0);
1349 			FLOAT_POP_CELL_POINTER_DOUBLE((dataTop--)->p);
1350 
1351 		case ficlInstructionFStore:
1352 			CHECK_FLOAT_STACK(1, 0);
1353 			CHECK_STACK(1, 0);
1354 			FLOAT_POP_CELL_POINTER((dataTop--)->p);
1355 #endif /* FICL_WANT_FLOAT */
1356 
1357 		/*
1358 		 * two-fetch CORE ( a-addr -- x1 x2 )
1359 		 *
1360 		 * Fetch the ficlCell pair x1 x2 stored at a-addr.
1361 		 * x2 is stored at a-addr and x1 at the next consecutive
1362 		 * ficlCell. It is equivalent to the sequence
1363 		 * DUP ficlCell+ @ SWAP @ .
1364 		 */
1365 		case ficlInstruction2Fetch:
1366 			CHECK_STACK(1, 2);
1367 			PUSH_CELL_POINTER_DOUBLE((dataTop--)->p);
1368 
1369 		/*
1370 		 * fetch CORE ( a-addr -- x )
1371 		 *
1372 		 * x is the value stored at a-addr.
1373 		 */
1374 		case ficlInstructionFetch:
1375 			CHECK_STACK(1, 1);
1376 			PUSH_CELL_POINTER((dataTop--)->p);
1377 
1378 		/*
1379 		 * two-store    CORE ( x1 x2 a-addr -- )
1380 		 * Store the ficlCell pair x1 x2 at a-addr, with x2 at a-addr
1381 		 * and x1 at the next consecutive ficlCell. It is equivalent
1382 		 * to the sequence SWAP OVER ! ficlCell+ !
1383 		 */
1384 		case ficlInstruction2Store:
1385 			CHECK_STACK(3, 0);
1386 			POP_CELL_POINTER_DOUBLE((dataTop--)->p);
1387 
1388 		/*
1389 		 * store	CORE ( x a-addr -- )
1390 		 * Store x at a-addr.
1391 		 */
1392 		case ficlInstructionStore:
1393 			CHECK_STACK(2, 0);
1394 			POP_CELL_POINTER((dataTop--)->p);
1395 
1396 		case ficlInstructionComma: {
1397 			ficlDictionary *dictionary;
1398 			CHECK_STACK(1, 0);
1399 
1400 			dictionary = ficlVmGetDictionary(vm);
1401 			ficlDictionaryAppendCell(dictionary, *dataTop--);
1402 			continue;
1403 		}
1404 
1405 		case ficlInstructionCComma: {
1406 			ficlDictionary *dictionary;
1407 			char c;
1408 			CHECK_STACK(1, 0);
1409 
1410 			dictionary = ficlVmGetDictionary(vm);
1411 			c = (char)(dataTop--)->i;
1412 			ficlDictionaryAppendCharacter(dictionary, c);
1413 			continue;
1414 		}
1415 
1416 		case ficlInstructionCells:
1417 			CHECK_STACK(1, 1);
1418 			dataTop->i *= sizeof (ficlCell);
1419 			continue;
1420 
1421 		case ficlInstructionCellPlus:
1422 			CHECK_STACK(1, 1);
1423 			dataTop->i += sizeof (ficlCell);
1424 			continue;
1425 
1426 		case ficlInstructionStar:
1427 			CHECK_STACK(2, 1);
1428 			i = (dataTop--)->i;
1429 			dataTop->i *= i;
1430 			continue;
1431 
1432 		case ficlInstructionNegate:
1433 			CHECK_STACK(1, 1);
1434 			dataTop->i = - dataTop->i;
1435 			continue;
1436 
1437 		case ficlInstructionSlash:
1438 			CHECK_STACK(2, 1);
1439 			i = (dataTop--)->i;
1440 			dataTop->i /= i;
1441 			continue;
1442 
1443 		/*
1444 		 * slash-mod	CORE ( n1 n2 -- n3 n4 )
1445 		 * Divide n1 by n2, giving the single-ficlCell remainder n3
1446 		 * and the single-ficlCell quotient n4. An ambiguous condition
1447 		 * exists if n2 is zero. If n1 and n2 differ in sign, the
1448 		 * implementation-defined result returned will be the
1449 		 * same as that returned by either the phrase
1450 		 * >R S>D R> FM/MOD or the phrase >R S>D R> SM/REM.
1451 		 * NOTE: Ficl complies with the second phrase
1452 		 * (symmetric division)
1453 		 */
1454 		case ficlInstructionSlashMod: {
1455 			ficl2Integer n1;
1456 			ficlInteger n2;
1457 			ficl2IntegerQR qr;
1458 
1459 			CHECK_STACK(2, 2);
1460 			n2    = dataTop[0].i;
1461 			FICL_INTEGER_TO_2INTEGER(dataTop[-1].i, n1);
1462 
1463 			qr = ficl2IntegerDivideSymmetric(n1, n2);
1464 			dataTop[-1].i = qr.remainder;
1465 			dataTop[0].i = FICL_2UNSIGNED_GET_LOW(qr.quotient);
1466 			continue;
1467 		}
1468 
1469 		case ficlInstruction2Star:
1470 			CHECK_STACK(1, 1);
1471 			dataTop->i <<= 1;
1472 			continue;
1473 
1474 		case ficlInstruction2Slash:
1475 			CHECK_STACK(1, 1);
1476 			dataTop->i >>= 1;
1477 			continue;
1478 
1479 		case ficlInstructionStarSlash: {
1480 			ficlInteger x, y, z;
1481 			ficl2Integer prod;
1482 			CHECK_STACK(3, 1);
1483 
1484 			z = (dataTop--)->i;
1485 			y = (dataTop--)->i;
1486 			x = dataTop->i;
1487 
1488 			prod = ficl2IntegerMultiply(x, y);
1489 			dataTop->i = FICL_2UNSIGNED_GET_LOW(
1490 			    ficl2IntegerDivideSymmetric(prod, z).quotient);
1491 			continue;
1492 		}
1493 
1494 		case ficlInstructionStarSlashMod: {
1495 			ficlInteger x, y, z;
1496 			ficl2Integer prod;
1497 			ficl2IntegerQR qr;
1498 
1499 			CHECK_STACK(3, 2);
1500 
1501 			z = (dataTop--)->i;
1502 			y = dataTop[0].i;
1503 			x = dataTop[-1].i;
1504 
1505 			prod = ficl2IntegerMultiply(x, y);
1506 			qr   = ficl2IntegerDivideSymmetric(prod, z);
1507 
1508 			dataTop[-1].i = qr.remainder;
1509 			dataTop[0].i = FICL_2UNSIGNED_GET_LOW(qr.quotient);
1510 			continue;
1511 		}
1512 
1513 #if FICL_WANT_FLOAT
1514 		case ficlInstructionF0:
1515 			CHECK_FLOAT_STACK(0, 1);
1516 			(++floatTop)->f = 0.0f;
1517 			continue;
1518 
1519 		case ficlInstructionF1:
1520 			CHECK_FLOAT_STACK(0, 1);
1521 			(++floatTop)->f = 1.0f;
1522 			continue;
1523 
1524 		case ficlInstructionFNeg1:
1525 			CHECK_FLOAT_STACK(0, 1);
1526 			(++floatTop)->f = -1.0f;
1527 			continue;
1528 
1529 		/*
1530 		 * Floating point literal execution word.
1531 		 */
1532 		case ficlInstructionFLiteralParen:
1533 			CHECK_FLOAT_STACK(0, 1);
1534 
1535 			/*
1536 			 * Yes, I'm using ->i here,
1537 			 * but it's really a float.  --lch
1538 			 */
1539 			(++floatTop)->i = *ip++;
1540 			continue;
1541 
1542 		/*
1543 		 * Do float addition r1 + r2.
1544 		 * f+ ( r1 r2 -- r )
1545 		 */
1546 		case ficlInstructionFPlus:
1547 			CHECK_FLOAT_STACK(2, 1);
1548 
1549 			f = (floatTop--)->f;
1550 			floatTop->f += f;
1551 			continue;
1552 
1553 		/*
1554 		 * Do float subtraction r1 - r2.
1555 		 * f- ( r1 r2 -- r )
1556 		 */
1557 		case ficlInstructionFMinus:
1558 			CHECK_FLOAT_STACK(2, 1);
1559 
1560 			f = (floatTop--)->f;
1561 			floatTop->f -= f;
1562 			continue;
1563 
1564 		/*
1565 		 * Do float multiplication r1 * r2.
1566 		 * f* ( r1 r2 -- r )
1567 		 */
1568 		case ficlInstructionFStar:
1569 			CHECK_FLOAT_STACK(2, 1);
1570 
1571 			f = (floatTop--)->f;
1572 			floatTop->f *= f;
1573 			continue;
1574 
1575 		/*
1576 		 * Do float negation.
1577 		 * fnegate ( r -- r )
1578 		 */
1579 		case ficlInstructionFNegate:
1580 			CHECK_FLOAT_STACK(1, 1);
1581 
1582 			floatTop->f = -(floatTop->f);
1583 			continue;
1584 
1585 		/*
1586 		 * Do float division r1 / r2.
1587 		 * f/ ( r1 r2 -- r )
1588 		 */
1589 		case ficlInstructionFSlash:
1590 			CHECK_FLOAT_STACK(2, 1);
1591 
1592 			f = (floatTop--)->f;
1593 			floatTop->f /= f;
1594 			continue;
1595 
1596 		/*
1597 		 * Do float + integer r + n.
1598 		 * f+i ( r n -- r )
1599 		 */
1600 		case ficlInstructionFPlusI:
1601 			CHECK_FLOAT_STACK(1, 1);
1602 			CHECK_STACK(1, 0);
1603 
1604 			f = (ficlFloat)(dataTop--)->f;
1605 			floatTop->f += f;
1606 			continue;
1607 
1608 		/*
1609 		 * Do float - integer r - n.
1610 		 * f-i ( r n -- r )
1611 		 */
1612 		case ficlInstructionFMinusI:
1613 			CHECK_FLOAT_STACK(1, 1);
1614 			CHECK_STACK(1, 0);
1615 
1616 			f = (ficlFloat)(dataTop--)->f;
1617 			floatTop->f -= f;
1618 			continue;
1619 
1620 		/*
1621 		 * Do float * integer r * n.
1622 		 * f*i ( r n -- r )
1623 		 */
1624 		case ficlInstructionFStarI:
1625 			CHECK_FLOAT_STACK(1, 1);
1626 			CHECK_STACK(1, 0);
1627 
1628 			f = (ficlFloat)(dataTop--)->f;
1629 			floatTop->f *= f;
1630 			continue;
1631 
1632 		/*
1633 		 * Do float / integer r / n.
1634 		 * f/i ( r n -- r )
1635 		 */
1636 		case ficlInstructionFSlashI:
1637 			CHECK_FLOAT_STACK(1, 1);
1638 			CHECK_STACK(1, 0);
1639 
1640 			f = (ficlFloat)(dataTop--)->f;
1641 			floatTop->f /= f;
1642 			continue;
1643 
1644 		/*
1645 		 * Do integer - float n - r.
1646 		 * i-f ( n r -- r )
1647 		 */
1648 		case ficlInstructionIMinusF:
1649 			CHECK_FLOAT_STACK(1, 1);
1650 			CHECK_STACK(1, 0);
1651 
1652 			f = (ficlFloat)(dataTop--)->f;
1653 			floatTop->f = f - floatTop->f;
1654 			continue;
1655 
1656 		/*
1657 		 * Do integer / float n / r.
1658 		 * i/f ( n r -- r )
1659 		 */
1660 		case ficlInstructionISlashF:
1661 			CHECK_FLOAT_STACK(1, 1);
1662 			CHECK_STACK(1, 0);
1663 
1664 			f = (ficlFloat)(dataTop--)->f;
1665 			floatTop->f = f / floatTop->f;
1666 			continue;
1667 
1668 		/*
1669 		 * Do integer to float conversion.
1670 		 * int>float ( n -- r )
1671 		 */
1672 		case ficlInstructionIntToFloat:
1673 			CHECK_STACK(1, 0);
1674 			CHECK_FLOAT_STACK(0, 1);
1675 
1676 			(++floatTop)->f = ((dataTop--)->f);
1677 			continue;
1678 
1679 		/*
1680 		 * Do float to integer conversion.
1681 		 * float>int ( r -- n )
1682 		 */
1683 		case ficlInstructionFloatToInt:
1684 			CHECK_STACK(0, 1);
1685 			CHECK_FLOAT_STACK(1, 0);
1686 
1687 			(++dataTop)->i = ((floatTop--)->i);
1688 			continue;
1689 
1690 		/*
1691 		 * Add a floating point number to contents of a variable.
1692 		 * f+! ( r n -- )
1693 		 */
1694 		case ficlInstructionFPlusStore: {
1695 			ficlCell *cell;
1696 
1697 			CHECK_STACK(1, 0);
1698 			CHECK_FLOAT_STACK(1, 0);
1699 
1700 			cell = (ficlCell *)(dataTop--)->p;
1701 			cell->f += (floatTop--)->f;
1702 			continue;
1703 		}
1704 
1705 		/*
1706 		 * Do float stack drop.
1707 		 * fdrop ( r -- )
1708 		 */
1709 		case ficlInstructionFDrop:
1710 			CHECK_FLOAT_STACK(1, 0);
1711 			floatTop--;
1712 			continue;
1713 
1714 		/*
1715 		 * Do float stack ?dup.
1716 		 * f?dup ( r -- r )
1717 		 */
1718 		case ficlInstructionFQuestionDup:
1719 			CHECK_FLOAT_STACK(1, 2);
1720 
1721 			if (floatTop->f != 0)
1722 				goto FDUP;
1723 
1724 			continue;
1725 
1726 		/*
1727 		 * Do float stack dup.
1728 		 * fdup ( r -- r r )
1729 		 */
1730 		case ficlInstructionFDup:
1731 			CHECK_FLOAT_STACK(1, 2);
1732 
1733 FDUP:
1734 			floatTop[1] = floatTop[0];
1735 			floatTop++;
1736 			continue;
1737 
1738 		/*
1739 		 * Do float stack swap.
1740 		 * fswap ( r1 r2 -- r2 r1 )
1741 		 */
1742 		case ficlInstructionFSwap:
1743 			CHECK_FLOAT_STACK(2, 2);
1744 
1745 			c = floatTop[0];
1746 			floatTop[0] = floatTop[-1];
1747 			floatTop[-1] = c;
1748 			continue;
1749 
1750 		/*
1751 		 * Do float stack 2drop.
1752 		 * f2drop ( r r -- )
1753 		 */
1754 		case ficlInstructionF2Drop:
1755 			CHECK_FLOAT_STACK(2, 0);
1756 
1757 			floatTop -= 2;
1758 			continue;
1759 
1760 		/*
1761 		 * Do float stack 2dup.
1762 		 * f2dup ( r1 r2 -- r1 r2 r1 r2 )
1763 		 */
1764 		case ficlInstructionF2Dup:
1765 			CHECK_FLOAT_STACK(2, 4);
1766 
1767 			floatTop[1] = floatTop[-1];
1768 			floatTop[2] = *floatTop;
1769 			floatTop += 2;
1770 			continue;
1771 
1772 		/*
1773 		 * Do float stack over.
1774 		 * fover ( r1 r2 -- r1 r2 r1 )
1775 		 */
1776 		case ficlInstructionFOver:
1777 			CHECK_FLOAT_STACK(2, 3);
1778 
1779 			floatTop[1] = floatTop[-1];
1780 			floatTop++;
1781 			continue;
1782 
1783 		/*
1784 		 * Do float stack 2over.
1785 		 * f2over ( r1 r2 r3 -- r1 r2 r3 r1 r2 )
1786 		 */
1787 		case ficlInstructionF2Over:
1788 			CHECK_FLOAT_STACK(4, 6);
1789 
1790 			floatTop[1] = floatTop[-2];
1791 			floatTop[2] = floatTop[-1];
1792 			floatTop += 2;
1793 			continue;
1794 
1795 		/*
1796 		 * Do float stack pick.
1797 		 * fpick ( n -- r )
1798 		 */
1799 		case ficlInstructionFPick:
1800 			CHECK_STACK(1, 0);
1801 			c = *dataTop--;
1802 			CHECK_FLOAT_STACK(c.i+2, c.i+3);
1803 
1804 			floatTop[1] = floatTop[- c.i - 1];
1805 			continue;
1806 
1807 		/*
1808 		 * Do float stack rot.
1809 		 * frot ( r1 r2 r3  -- r2 r3 r1 )
1810 		 */
1811 		case ficlInstructionFRot:
1812 			i = 2;
1813 		goto FROLL;
1814 
1815 		/*
1816 		 * Do float stack roll.
1817 		 * froll ( n -- )
1818 		 */
1819 		case ficlInstructionFRoll:
1820 			CHECK_STACK(1, 0);
1821 			i = (dataTop--)->i;
1822 
1823 			if (i < 1)
1824 				continue;
1825 
1826 FROLL:
1827 			CHECK_FLOAT_STACK(i+1, i+2);
1828 			c = floatTop[-i];
1829 			memmove(floatTop - i, floatTop - (i - 1),
1830 			    i * sizeof (ficlCell));
1831 			*floatTop = c;
1832 
1833 			continue;
1834 
1835 		/*
1836 		 * Do float stack -rot.
1837 		 * f-rot ( r1 r2 r3  -- r3 r1 r2 )
1838 		 */
1839 		case ficlInstructionFMinusRot:
1840 			i = 2;
1841 			goto FMINUSROLL;
1842 
1843 
1844 		/*
1845 		 * Do float stack -roll.
1846 		 * f-roll ( n -- )
1847 		 */
1848 		case ficlInstructionFMinusRoll:
1849 			CHECK_STACK(1, 0);
1850 			i = (dataTop--)->i;
1851 
1852 			if (i < 1)
1853 				continue;
1854 
1855 FMINUSROLL:
1856 			CHECK_FLOAT_STACK(i+1, i+2);
1857 			c = *floatTop;
1858 			memmove(floatTop - (i - 1), floatTop - i,
1859 			    i * sizeof (ficlCell));
1860 			floatTop[-i] = c;
1861 
1862 			continue;
1863 
1864 		/*
1865 		 * Do float stack 2swap
1866 		 * f2swap ( r1 r2 r3 r4  -- r3 r4 r1 r2 )
1867 		 */
1868 		case ficlInstructionF2Swap: {
1869 			ficlCell c2;
1870 			CHECK_FLOAT_STACK(4, 4);
1871 
1872 			c = *floatTop;
1873 			c2 = floatTop[-1];
1874 
1875 			*floatTop = floatTop[-2];
1876 			floatTop[-1] = floatTop[-3];
1877 
1878 			floatTop[-2] = c;
1879 			floatTop[-3] = c2;
1880 			continue;
1881 		}
1882 
1883 		/*
1884 		 * Do float 0= comparison r = 0.0.
1885 		 * f0= ( r -- T/F )
1886 		 */
1887 		case ficlInstructionF0Equals:
1888 			CHECK_FLOAT_STACK(1, 0);
1889 			CHECK_STACK(0, 1);
1890 
1891 			(++dataTop)->i = FICL_BOOL((floatTop--)->f != 0.0f);
1892 			continue;
1893 
1894 		/*
1895 		 * Do float 0< comparison r < 0.0.
1896 		 * f0< ( r -- T/F )
1897 		 */
1898 		case ficlInstructionF0Less:
1899 			CHECK_FLOAT_STACK(1, 0);
1900 			CHECK_STACK(0, 1);
1901 
1902 			(++dataTop)->i = FICL_BOOL((floatTop--)->f < 0.0f);
1903 			continue;
1904 
1905 		/*
1906 		 * Do float 0> comparison r > 0.0.
1907 		 * f0> ( r -- T/F )
1908 		 */
1909 		case ficlInstructionF0Greater:
1910 			CHECK_FLOAT_STACK(1, 0);
1911 			CHECK_STACK(0, 1);
1912 
1913 			(++dataTop)->i = FICL_BOOL((floatTop--)->f > 0.0f);
1914 			continue;
1915 
1916 		/*
1917 		 * Do float = comparison r1 = r2.
1918 		 * f= ( r1 r2 -- T/F )
1919 		 */
1920 		case ficlInstructionFEquals:
1921 			CHECK_FLOAT_STACK(2, 0);
1922 			CHECK_STACK(0, 1);
1923 
1924 			f = (floatTop--)->f;
1925 			(++dataTop)->i = FICL_BOOL((floatTop--)->f == f);
1926 			continue;
1927 
1928 		/*
1929 		 * Do float < comparison r1 < r2.
1930 		 * f< ( r1 r2 -- T/F )
1931 		 */
1932 		case ficlInstructionFLess:
1933 			CHECK_FLOAT_STACK(2, 0);
1934 			CHECK_STACK(0, 1);
1935 
1936 			f = (floatTop--)->f;
1937 			(++dataTop)->i = FICL_BOOL((floatTop--)->f < f);
1938 			continue;
1939 
1940 		/*
1941 		 * Do float > comparison r1 > r2.
1942 		 * f> ( r1 r2 -- T/F )
1943 		 */
1944 		case ficlInstructionFGreater:
1945 			CHECK_FLOAT_STACK(2, 0);
1946 			CHECK_STACK(0, 1);
1947 
1948 			f = (floatTop--)->f;
1949 			(++dataTop)->i = FICL_BOOL((floatTop--)->f > f);
1950 			continue;
1951 
1952 
1953 		/*
1954 		 * Move float to param stack (assumes they both fit in a
1955 		 * single ficlCell) f>s
1956 		 */
1957 		case ficlInstructionFFrom:
1958 			CHECK_FLOAT_STACK(1, 0);
1959 			CHECK_STACK(0, 1);
1960 
1961 			*++dataTop = *floatTop--;
1962 			continue;
1963 
1964 		case ficlInstructionToF:
1965 			CHECK_FLOAT_STACK(0, 1);
1966 			CHECK_STACK(1, 0);
1967 
1968 			*++floatTop = *dataTop--;
1969 			continue;
1970 
1971 #endif /* FICL_WANT_FLOAT */
1972 
1973 		/*
1974 		 * c o l o n P a r e n
1975 		 * This is the code that executes a colon definition. It
1976 		 * assumes that the virtual machine is running a "next" loop
1977 		 * (See the vm.c for its implementation of member function
1978 		 * vmExecute()). The colon code simply copies the address of
1979 		 * the first word in the list of words to interpret into IP
1980 		 * after saving its old value. When we return to the "next"
1981 		 * loop, the virtual machine will call the code for each
1982 		 * word in turn.
1983 		 */
1984 		case ficlInstructionColonParen:
1985 			(++returnTop)->p = (void *)ip;
1986 			ip = (ficlInstruction *)(fw->param);
1987 			continue;
1988 
1989 		case ficlInstructionCreateParen:
1990 			CHECK_STACK(0, 1);
1991 			(++dataTop)->p = (fw->param + 1);
1992 			continue;
1993 
1994 		case ficlInstructionVariableParen:
1995 			CHECK_STACK(0, 1);
1996 			(++dataTop)->p = fw->param;
1997 			continue;
1998 
1999 		/*
2000 		 * c o n s t a n t P a r e n
2001 		 * This is the run-time code for "constant". It simply returns
2002 		 * the contents of its word's first data ficlCell.
2003 		 */
2004 
2005 #if FICL_WANT_FLOAT
2006 		case ficlInstructionF2ConstantParen:
2007 			CHECK_FLOAT_STACK(0, 2);
2008 			FLOAT_PUSH_CELL_POINTER_DOUBLE(fw->param);
2009 
2010 		case ficlInstructionFConstantParen:
2011 			CHECK_FLOAT_STACK(0, 1);
2012 			FLOAT_PUSH_CELL_POINTER(fw->param);
2013 #endif /* FICL_WANT_FLOAT */
2014 
2015 		case ficlInstruction2ConstantParen:
2016 			CHECK_STACK(0, 2);
2017 			PUSH_CELL_POINTER_DOUBLE(fw->param);
2018 
2019 		case ficlInstructionConstantParen:
2020 			CHECK_STACK(0, 1);
2021 			PUSH_CELL_POINTER(fw->param);
2022 
2023 #if FICL_WANT_USER
2024 		case ficlInstructionUserParen: {
2025 			ficlInteger i = fw->param[0].i;
2026 			(++dataTop)->p = &vm->user[i];
2027 			continue;
2028 		}
2029 #endif
2030 
2031 		default:
2032 		/*
2033 		 * Clever hack, or evil coding?  You be the judge.
2034 		 *
2035 		 * If the word we've been asked to execute is in fact
2036 		 * an *instruction*, we grab the instruction, stow it
2037 		 * in "i" (our local cache of *ip), and *jump* to the
2038 		 * top of the switch statement.  --lch
2039 		 */
2040 			if (((ficlInstruction)fw->code >
2041 			    ficlInstructionInvalid) &&
2042 			    ((ficlInstruction)fw->code < ficlInstructionLast)) {
2043 				instruction = (ficlInstruction)fw->code;
2044 				goto AGAIN;
2045 			}
2046 
2047 			LOCAL_VARIABLE_SPILL;
2048 			(vm)->runningWord = fw;
2049 			fw->code(vm);
2050 			LOCAL_VARIABLE_REFILL;
2051 			continue;
2052 		}
2053 	}
2054 
2055 	LOCAL_VARIABLE_SPILL;
2056 	vm->exceptionHandler = oldExceptionHandler;
2057 }
2058 
2059 /*
2060  * v m G e t D i c t
2061  * Returns the address dictionary for this VM's system
2062  */
2063 ficlDictionary *
2064 ficlVmGetDictionary(ficlVm *vm)
2065 {
2066 	FICL_VM_ASSERT(vm, vm);
2067 	return (vm->callback.system->dictionary);
2068 }
2069 
2070 /*
2071  * v m G e t S t r i n g
2072  * Parses a string out of the VM input buffer and copies up to the first
2073  * FICL_COUNTED_STRING_MAX characters to the supplied destination buffer, a
2074  * ficlCountedString. The destination string is NULL terminated.
2075  *
2076  * Returns the address of the first unused character in the dest buffer.
2077  */
2078 char *
2079 ficlVmGetString(ficlVm *vm, ficlCountedString *counted, char delimiter)
2080 {
2081 	ficlString s = ficlVmParseStringEx(vm, delimiter, 0);
2082 
2083 	if (FICL_STRING_GET_LENGTH(s) > FICL_COUNTED_STRING_MAX) {
2084 		FICL_STRING_SET_LENGTH(s, FICL_COUNTED_STRING_MAX);
2085 	}
2086 
2087 	(void) strncpy(counted->text, FICL_STRING_GET_POINTER(s),
2088 	    FICL_STRING_GET_LENGTH(s));
2089 	counted->text[FICL_STRING_GET_LENGTH(s)] = '\0';
2090 	counted->length = (ficlUnsigned8)FICL_STRING_GET_LENGTH(s);
2091 
2092 	return (counted->text + FICL_STRING_GET_LENGTH(s) + 1);
2093 }
2094 
2095 /*
2096  * v m G e t W o r d
2097  * vmGetWord calls vmGetWord0 repeatedly until it gets a string with
2098  * non-zero length.
2099  */
2100 ficlString
2101 ficlVmGetWord(ficlVm *vm)
2102 {
2103 	ficlString s = ficlVmGetWord0(vm);
2104 
2105 	if (FICL_STRING_GET_LENGTH(s) == 0) {
2106 		ficlVmThrow(vm, FICL_VM_STATUS_RESTART);
2107 	}
2108 
2109 	return (s);
2110 }
2111 
2112 /*
2113  * v m G e t W o r d 0
2114  * Skip leading whitespace and parse a space delimited word from the tib.
2115  * Returns the start address and length of the word. Updates the tib
2116  * to reflect characters consumed, including the trailing delimiter.
2117  * If there's nothing of interest in the tib, returns zero. This function
2118  * does not use vmParseString because it uses isspace() rather than a
2119  * single  delimiter character.
2120  */
2121 ficlString
2122 ficlVmGetWord0(ficlVm *vm)
2123 {
2124 	char *trace = ficlVmGetInBuf(vm);
2125 	char *stop = ficlVmGetInBufEnd(vm);
2126 	ficlString s;
2127 	ficlUnsigned length = 0;
2128 	char c = 0;
2129 
2130 	trace = ficlStringSkipSpace(trace, stop);
2131 	FICL_STRING_SET_POINTER(s, trace);
2132 
2133 	/* Please leave this loop this way; it makes Purify happier.  --lch */
2134 	for (;;) {
2135 		if (trace == stop)
2136 			break;
2137 		c = *trace;
2138 		if (isspace((unsigned char)c))
2139 			break;
2140 		length++;
2141 		trace++;
2142 	}
2143 
2144 	FICL_STRING_SET_LENGTH(s, length);
2145 
2146 	/* skip one trailing delimiter */
2147 	if ((trace != stop) && isspace((unsigned char)c))
2148 		trace++;
2149 
2150 	ficlVmUpdateTib(vm, trace);
2151 
2152 	return (s);
2153 }
2154 
2155 /*
2156  * v m G e t W o r d T o P a d
2157  * Does vmGetWord and copies the result to the pad as a NULL terminated
2158  * string. Returns the length of the string. If the string is too long
2159  * to fit in the pad, it is truncated.
2160  */
2161 int
2162 ficlVmGetWordToPad(ficlVm *vm)
2163 {
2164 	ficlString s;
2165 	char *pad = (char *)vm->pad;
2166 	s = ficlVmGetWord(vm);
2167 
2168 	if (FICL_STRING_GET_LENGTH(s) > FICL_PAD_SIZE)
2169 		FICL_STRING_SET_LENGTH(s, FICL_PAD_SIZE);
2170 
2171 	(void) strncpy(pad, FICL_STRING_GET_POINTER(s),
2172 	    FICL_STRING_GET_LENGTH(s));
2173 	pad[FICL_STRING_GET_LENGTH(s)] = '\0';
2174 	return ((int)(FICL_STRING_GET_LENGTH(s)));
2175 }
2176 
2177 /*
2178  * v m P a r s e S t r i n g
2179  * Parses a string out of the input buffer using the delimiter
2180  * specified. Skips leading delimiters, marks the start of the string,
2181  * and counts characters to the next delimiter it encounters. It then
2182  * updates the vm input buffer to consume all these chars, including the
2183  * trailing delimiter.
2184  * Returns the address and length of the parsed string, not including the
2185  * trailing delimiter.
2186  */
2187 ficlString
2188 ficlVmParseString(ficlVm *vm, char delimiter)
2189 {
2190 	return (ficlVmParseStringEx(vm, delimiter, 1));
2191 }
2192 
2193 ficlString
2194 ficlVmParseStringEx(ficlVm *vm, char delimiter, char skipLeadingDelimiters)
2195 {
2196 	ficlString s;
2197 	char *trace = ficlVmGetInBuf(vm);
2198 	char *stop = ficlVmGetInBufEnd(vm);
2199 	char c;
2200 
2201 	if (skipLeadingDelimiters) {
2202 		while ((trace != stop) && (*trace == delimiter))
2203 			trace++;
2204 	}
2205 
2206 	FICL_STRING_SET_POINTER(s, trace);    /* mark start of text */
2207 
2208 	/* find next delimiter or end of line */
2209 	for (c = *trace;
2210 	    (trace != stop) && (c != delimiter) && (c != '\r') && (c != '\n');
2211 	    c = *++trace) {
2212 		;
2213 	}
2214 
2215 	/* set length of result */
2216 	FICL_STRING_SET_LENGTH(s, trace - FICL_STRING_GET_POINTER(s));
2217 
2218 	/* gobble trailing delimiter */
2219 	if ((trace != stop) && (*trace == delimiter))
2220 		trace++;
2221 
2222 	ficlVmUpdateTib(vm, trace);
2223 	return (s);
2224 }
2225 
2226 
2227 /*
2228  * v m P o p
2229  */
2230 ficlCell
2231 ficlVmPop(ficlVm *vm)
2232 {
2233 	return (ficlStackPop(vm->dataStack));
2234 }
2235 
2236 /*
2237  * v m P u s h
2238  */
2239 void
2240 ficlVmPush(ficlVm *vm, ficlCell c)
2241 {
2242 	ficlStackPush(vm->dataStack, c);
2243 }
2244 
2245 /*
2246  * v m P o p I P
2247  */
2248 void
2249 ficlVmPopIP(ficlVm *vm)
2250 {
2251 	vm->ip = (ficlIp)(ficlStackPopPointer(vm->returnStack));
2252 }
2253 
2254 /*
2255  * v m P u s h I P
2256  */
2257 void
2258 ficlVmPushIP(ficlVm *vm, ficlIp newIP)
2259 {
2260 	ficlStackPushPointer(vm->returnStack, (void *)vm->ip);
2261 	vm->ip = newIP;
2262 }
2263 
2264 /*
2265  * v m P u s h T i b
2266  * Binds the specified input string to the VM and clears >IN (the index)
2267  */
2268 void
2269 ficlVmPushTib(ficlVm *vm, char *text, ficlInteger nChars, ficlTIB *pSaveTib)
2270 {
2271 	if (pSaveTib) {
2272 		*pSaveTib = vm->tib;
2273 	}
2274 	vm->tib.text = text;
2275 	vm->tib.end = text + nChars;
2276 	vm->tib.index = 0;
2277 }
2278 
2279 void
2280 ficlVmPopTib(ficlVm *vm, ficlTIB *pTib)
2281 {
2282 	if (pTib) {
2283 		vm->tib = *pTib;
2284 	}
2285 }
2286 
2287 /*
2288  * v m Q u i t
2289  */
2290 void
2291 ficlVmQuit(ficlVm *vm)
2292 {
2293 	ficlStackReset(vm->returnStack);
2294 	vm->restart = 0;
2295 	vm->ip = NULL;
2296 	vm->runningWord = NULL;
2297 	vm->state = FICL_VM_STATE_INTERPRET;
2298 	vm->tib.text = NULL;
2299 	vm->tib.end = NULL;
2300 	vm->tib.index = 0;
2301 	vm->pad[0] = '\0';
2302 	vm->sourceId.i = 0;
2303 }
2304 
2305 /*
2306  * v m R e s e t
2307  */
2308 void
2309 ficlVmReset(ficlVm *vm)
2310 {
2311 	ficlVmQuit(vm);
2312 	ficlStackReset(vm->dataStack);
2313 #if FICL_WANT_FLOAT
2314 	ficlStackReset(vm->floatStack);
2315 #endif
2316 	vm->base = 10;
2317 }
2318 
2319 /*
2320  * v m S e t T e x t O u t
2321  * Binds the specified output callback to the vm. If you pass NULL,
2322  * binds the default output function (ficlTextOut)
2323  */
2324 void
2325 ficlVmSetTextOut(ficlVm *vm, ficlOutputFunction textOut)
2326 {
2327 	vm->callback.textOut = textOut;
2328 }
2329 
2330 void
2331 ficlVmTextOut(ficlVm *vm, char *text)
2332 {
2333 	ficlCallbackTextOut((ficlCallback *)vm, text);
2334 }
2335 
2336 
2337 void
2338 ficlVmErrorOut(ficlVm *vm, char *text)
2339 {
2340 	ficlCallbackErrorOut((ficlCallback *)vm, text);
2341 }
2342 
2343 
2344 /*
2345  * v m T h r o w
2346  */
2347 void
2348 ficlVmThrow(ficlVm *vm, int except)
2349 {
2350 	if (vm->exceptionHandler)
2351 		longjmp(*(vm->exceptionHandler), except);
2352 }
2353 
2354 void
2355 ficlVmThrowError(ficlVm *vm, char *fmt, ...)
2356 {
2357 	va_list list;
2358 
2359 	va_start(list, fmt);
2360 	(void) vsprintf(vm->pad, fmt, list);
2361 	va_end(list);
2362 	(void) strcat(vm->pad, "\n");
2363 
2364 	ficlVmErrorOut(vm, vm->pad);
2365 	longjmp(*(vm->exceptionHandler), FICL_VM_STATUS_ERROR_EXIT);
2366 }
2367 
2368 void
2369 ficlVmThrowErrorVararg(ficlVm *vm, char *fmt, va_list list)
2370 {
2371 	(void) vsprintf(vm->pad, fmt, list);
2372 	/*
2373 	 * well, we can try anyway, we're certainly not
2374 	 * returning to our caller!
2375 	 */
2376 	va_end(list);
2377 	(void) strcat(vm->pad, "\n");
2378 
2379 	ficlVmErrorOut(vm, vm->pad);
2380 	longjmp(*(vm->exceptionHandler), FICL_VM_STATUS_ERROR_EXIT);
2381 }
2382 
2383 /*
2384  * f i c l E v a l u a t e
2385  * Wrapper for ficlExec() which sets SOURCE-ID to -1.
2386  */
2387 int
2388 ficlVmEvaluate(ficlVm *vm, char *s)
2389 {
2390 	int returnValue;
2391 	ficlCell id = vm->sourceId;
2392 	ficlString string;
2393 	vm->sourceId.i = -1;
2394 	FICL_STRING_SET_FROM_CSTRING(string, s);
2395 	returnValue = ficlVmExecuteString(vm, string);
2396 	vm->sourceId = id;
2397 	return (returnValue);
2398 }
2399 
2400 /*
2401  * f i c l E x e c
2402  * Evaluates a block of input text in the context of the
2403  * specified interpreter. Emits any requested output to the
2404  * interpreter's output function.
2405  *
2406  * Contains the "inner interpreter" code in a tight loop
2407  *
2408  * Returns one of the VM_XXXX codes defined in ficl.h:
2409  * VM_OUTOFTEXT is the normal exit condition
2410  * VM_ERREXIT means that the interpreter encountered a syntax error
2411  *      and the vm has been reset to recover (some or all
2412  *      of the text block got ignored
2413  * VM_USEREXIT means that the user executed the "bye" command
2414  *      to shut down the interpreter. This would be a good
2415  *      time to delete the vm, etc -- or you can ignore this
2416  *      signal.
2417  */
2418 int
2419 ficlVmExecuteString(ficlVm *vm, ficlString s)
2420 {
2421 	ficlSystem *system = vm->callback.system;
2422 	ficlDictionary *dictionary = system->dictionary;
2423 
2424 	int except;
2425 	jmp_buf vmState;
2426 	jmp_buf *oldState;
2427 	ficlTIB saveficlTIB;
2428 
2429 	FICL_VM_ASSERT(vm, vm);
2430 	FICL_VM_ASSERT(vm, system->interpreterLoop[0]);
2431 
2432 	ficlVmPushTib(vm, FICL_STRING_GET_POINTER(s),
2433 	    FICL_STRING_GET_LENGTH(s), &saveficlTIB);
2434 
2435 	/*
2436 	 * Save and restore VM's jmp_buf to enable nested calls to ficlExec
2437 	 */
2438 	oldState = vm->exceptionHandler;
2439 
2440 	/* This has to come before the setjmp! */
2441 	vm->exceptionHandler = &vmState;
2442 	except = setjmp(vmState);
2443 
2444 	switch (except) {
2445 	case 0:
2446 		if (vm->restart) {
2447 			vm->runningWord->code(vm);
2448 			vm->restart = 0;
2449 		} else {	/* set VM up to interpret text */
2450 			ficlVmPushIP(vm, &(system->interpreterLoop[0]));
2451 		}
2452 
2453 		ficlVmInnerLoop(vm, 0);
2454 	break;
2455 
2456 	case FICL_VM_STATUS_RESTART:
2457 		vm->restart = 1;
2458 		except = FICL_VM_STATUS_OUT_OF_TEXT;
2459 	break;
2460 
2461 	case FICL_VM_STATUS_OUT_OF_TEXT:
2462 		ficlVmPopIP(vm);
2463 #if 0	/* we dont output prompt in loader */
2464 		if ((vm->state != FICL_VM_STATE_COMPILE) &&
2465 		    (vm->sourceId.i == 0))
2466 			ficlVmTextOut(vm, FICL_PROMPT);
2467 #endif
2468 	break;
2469 
2470 	case FICL_VM_STATUS_USER_EXIT:
2471 	case FICL_VM_STATUS_INNER_EXIT:
2472 	case FICL_VM_STATUS_BREAK:
2473 	break;
2474 
2475 	case FICL_VM_STATUS_QUIT:
2476 		if (vm->state == FICL_VM_STATE_COMPILE) {
2477 			ficlDictionaryAbortDefinition(dictionary);
2478 #if FICL_WANT_LOCALS
2479 			ficlDictionaryEmpty(system->locals,
2480 			    system->locals->forthWordlist->size);
2481 #endif
2482 		}
2483 		ficlVmQuit(vm);
2484 	break;
2485 
2486 	case FICL_VM_STATUS_ERROR_EXIT:
2487 	case FICL_VM_STATUS_ABORT:
2488 	case FICL_VM_STATUS_ABORTQ:
2489 	default:		/* user defined exit code?? */
2490 		if (vm->state == FICL_VM_STATE_COMPILE) {
2491 			ficlDictionaryAbortDefinition(dictionary);
2492 #if FICL_WANT_LOCALS
2493 			ficlDictionaryEmpty(system->locals,
2494 			    system->locals->forthWordlist->size);
2495 #endif
2496 		}
2497 		ficlDictionaryResetSearchOrder(dictionary);
2498 		ficlVmReset(vm);
2499 	break;
2500 	}
2501 
2502 	vm->exceptionHandler = oldState;
2503 	ficlVmPopTib(vm, &saveficlTIB);
2504 	return (except);
2505 }
2506 
2507 /*
2508  * f i c l E x e c X T
2509  * Given a pointer to a ficlWord, push an inner interpreter and
2510  * execute the word to completion. This is in contrast with vmExecute,
2511  * which does not guarantee that the word will have completed when
2512  * the function returns (ie in the case of colon definitions, which
2513  * need an inner interpreter to finish)
2514  *
2515  * Returns one of the VM_XXXX exception codes listed in ficl.h. Normal
2516  * exit condition is VM_INNEREXIT, Ficl's private signal to exit the
2517  * inner loop under normal circumstances. If another code is thrown to
2518  * exit the loop, this function will re-throw it if it's nested under
2519  * itself or ficlExec.
2520  *
2521  * NOTE: this function is intended so that C code can execute ficlWords
2522  * given their address in the dictionary (xt).
2523  */
2524 int
2525 ficlVmExecuteXT(ficlVm *vm, ficlWord *pWord)
2526 {
2527 	int except;
2528 	jmp_buf vmState;
2529 	jmp_buf *oldState;
2530 	ficlWord *oldRunningWord;
2531 
2532 	FICL_VM_ASSERT(vm, vm);
2533 	FICL_VM_ASSERT(vm, vm->callback.system->exitInnerWord);
2534 
2535 	/*
2536 	 * Save the runningword so that RESTART behaves correctly
2537 	 * over nested calls.
2538 	 */
2539 	oldRunningWord = vm->runningWord;
2540 	/*
2541 	 * Save and restore VM's jmp_buf to enable nested calls
2542 	 */
2543 	oldState = vm->exceptionHandler;
2544 	/* This has to come before the setjmp! */
2545 	vm->exceptionHandler = &vmState;
2546 	except = setjmp(vmState);
2547 
2548 	if (except)
2549 		ficlVmPopIP(vm);
2550 	else
2551 		ficlVmPushIP(vm, &(vm->callback.system->exitInnerWord));
2552 
2553 	switch (except) {
2554 	case 0:
2555 		ficlVmExecuteWord(vm, pWord);
2556 		ficlVmInnerLoop(vm, 0);
2557 	break;
2558 
2559 	case FICL_VM_STATUS_INNER_EXIT:
2560 	case FICL_VM_STATUS_BREAK:
2561 	break;
2562 
2563 	case FICL_VM_STATUS_RESTART:
2564 	case FICL_VM_STATUS_OUT_OF_TEXT:
2565 	case FICL_VM_STATUS_USER_EXIT:
2566 	case FICL_VM_STATUS_QUIT:
2567 	case FICL_VM_STATUS_ERROR_EXIT:
2568 	case FICL_VM_STATUS_ABORT:
2569 	case FICL_VM_STATUS_ABORTQ:
2570 	default:		/* user defined exit code?? */
2571 		if (oldState) {
2572 			vm->exceptionHandler = oldState;
2573 			ficlVmThrow(vm, except);
2574 		}
2575 	break;
2576 	}
2577 
2578 	vm->exceptionHandler = oldState;
2579 	vm->runningWord = oldRunningWord;
2580 	return (except);
2581 }
2582 
2583 /*
2584  * f i c l P a r s e N u m b e r
2585  * Attempts to convert the NULL terminated string in the VM's pad to
2586  * a number using the VM's current base. If successful, pushes the number
2587  * onto the param stack and returns FICL_TRUE. Otherwise, returns FICL_FALSE.
2588  * (jws 8/01) Trailing decimal point causes a zero ficlCell to be pushed. (See
2589  * the standard for DOUBLE wordset.
2590  */
2591 int
2592 ficlVmParseNumber(ficlVm *vm, ficlString s)
2593 {
2594 	ficlInteger accumulator = 0;
2595 	char isNegative = 0;
2596 	char isDouble = 0;
2597 	unsigned base = vm->base;
2598 	char *trace = FICL_STRING_GET_POINTER(s);
2599 	ficlUnsigned8 length = (ficlUnsigned8)FICL_STRING_GET_LENGTH(s);
2600 	unsigned c;
2601 	unsigned digit;
2602 
2603 	if (length > 1) {
2604 		switch (*trace) {
2605 		case '-':
2606 			trace++;
2607 			length--;
2608 			isNegative = 1;
2609 		break;
2610 		case '+':
2611 			trace++;
2612 			length--;
2613 			isNegative = 0;
2614 		break;
2615 		default:
2616 		break;
2617 		}
2618 	}
2619 
2620 	/* detect & remove trailing decimal */
2621 	if ((length > 0) && (trace[length - 1] == '.')) {
2622 		isDouble = 1;
2623 		length--;
2624 	}
2625 
2626 	if (length == 0)		/* detect "+", "-", ".", "+." etc */
2627 		return (0);		/* false */
2628 
2629 	while ((length--) && ((c = *trace++) != '\0')) {
2630 		if (!isalnum(c))
2631 			return (0);	/* false */
2632 
2633 		digit = c - '0';
2634 
2635 		if (digit > 9)
2636 			digit = tolower(c) - 'a' + 10;
2637 
2638 		if (digit >= base)
2639 			return (0);	/* false */
2640 
2641 		accumulator = accumulator * base + digit;
2642 	}
2643 
2644 	if (isNegative)
2645 		accumulator = -accumulator;
2646 
2647 	ficlStackPushInteger(vm->dataStack, accumulator);
2648 	if (vm->state == FICL_VM_STATE_COMPILE)
2649 		ficlPrimitiveLiteralIm(vm);
2650 
2651 	if (isDouble) {			/* simple (required) DOUBLE support */
2652 		if (isNegative)
2653 			ficlStackPushInteger(vm->dataStack, -1);
2654 		else
2655 			ficlStackPushInteger(vm->dataStack, 0);
2656 		if (vm->state == FICL_VM_STATE_COMPILE)
2657 			ficlPrimitiveLiteralIm(vm);
2658 	}
2659 
2660 	return (1); /* true */
2661 }
2662 
2663 /*
2664  * d i c t C h e c k
2665  * Checks the dictionary for corruption and throws appropriate
2666  * errors.
2667  * Input: +n number of ADDRESS UNITS (not ficlCells) proposed to allot
2668  *        -n number of ADDRESS UNITS proposed to de-allot
2669  *         0 just do a consistency check
2670  */
2671 void
2672 ficlVmDictionarySimpleCheck(ficlVm *vm, ficlDictionary *dictionary, int cells)
2673 {
2674 #if FICL_ROBUST >= 1
2675 	if ((cells >= 0) &&
2676 	    (ficlDictionaryCellsAvailable(dictionary) *
2677 	    (int)sizeof (ficlCell) < cells)) {
2678 		ficlVmThrowError(vm, "Error: dictionary full");
2679 	}
2680 
2681 	if ((cells <= 0) &&
2682 	    (ficlDictionaryCellsUsed(dictionary) *
2683 	    (int)sizeof (ficlCell) < -cells)) {
2684 		ficlVmThrowError(vm, "Error: dictionary underflow");
2685 	}
2686 #else /* FICL_ROBUST >= 1 */
2687 	FICL_IGNORE(vm);
2688 	FICL_IGNORE(dictionary);
2689 	FICL_IGNORE(cells);
2690 #endif /* FICL_ROBUST >= 1 */
2691 }
2692 
2693 void
2694 ficlVmDictionaryCheck(ficlVm *vm, ficlDictionary *dictionary, int cells)
2695 {
2696 #if FICL_ROBUST >= 1
2697 	ficlVmDictionarySimpleCheck(vm, dictionary, cells);
2698 
2699 	if (dictionary->wordlistCount > FICL_MAX_WORDLISTS) {
2700 		ficlDictionaryResetSearchOrder(dictionary);
2701 		ficlVmThrowError(vm, "Error: search order overflow");
2702 	} else if (dictionary->wordlistCount < 0) {
2703 		ficlDictionaryResetSearchOrder(dictionary);
2704 		ficlVmThrowError(vm, "Error: search order underflow");
2705 	}
2706 #else /* FICL_ROBUST >= 1 */
2707 	FICL_IGNORE(vm);
2708 	FICL_IGNORE(dictionary);
2709 	FICL_IGNORE(cells);
2710 #endif /* FICL_ROBUST >= 1 */
2711 }
2712 
2713 void
2714 ficlVmDictionaryAllot(ficlVm *vm, ficlDictionary *dictionary, int n)
2715 {
2716 	FICL_VM_DICTIONARY_SIMPLE_CHECK(vm, dictionary, n);
2717 	FICL_IGNORE(vm);
2718 	ficlDictionaryAllot(dictionary, n);
2719 }
2720 
2721 void
2722 ficlVmDictionaryAllotCells(ficlVm *vm, ficlDictionary *dictionary, int cells)
2723 {
2724 	FICL_VM_DICTIONARY_SIMPLE_CHECK(vm, dictionary, cells);
2725 	FICL_IGNORE(vm);
2726 	ficlDictionaryAllotCells(dictionary, cells);
2727 }
2728 
2729 /*
2730  * f i c l P a r s e W o r d
2731  * From the standard, section 3.4
2732  * b) Search the dictionary name space (see 3.4.2). If a definition name
2733  * matching the string is found:
2734  *  1.if interpreting, perform the interpretation semantics of the definition
2735  *  (see 3.4.3.2), and continue at a);
2736  *  2.if compiling, perform the compilation semantics of the definition
2737  *  (see 3.4.3.3), and continue at a).
2738  *
2739  * c) If a definition name matching the string is not found, attempt to
2740  * convert the string to a number (see 3.4.1.3). If successful:
2741  *  1.if interpreting, place the number on the data stack, and continue at a);
2742  *  2.if compiling, FICL_VM_STATE_COMPILE code that when executed will place
2743  *  the number on the stack (see 6.1.1780 LITERAL), and continue at a);
2744  *
2745  * d) If unsuccessful, an ambiguous condition exists (see 3.4.4).
2746  *
2747  * (jws 4/01) Modified to be a ficlParseStep
2748  */
2749 int
2750 ficlVmParseWord(ficlVm *vm, ficlString name)
2751 {
2752 	ficlDictionary *dictionary = ficlVmGetDictionary(vm);
2753 	ficlWord *tempFW;
2754 
2755 	FICL_VM_DICTIONARY_CHECK(vm, dictionary, 0);
2756 	FICL_STACK_CHECK(vm->dataStack, 0, 0);
2757 
2758 #if FICL_WANT_LOCALS
2759 	if (vm->callback.system->localsCount > 0) {
2760 		tempFW = ficlSystemLookupLocal(vm->callback.system, name);
2761 	} else
2762 #endif
2763 		tempFW = ficlDictionaryLookup(dictionary, name);
2764 
2765 	if (vm->state == FICL_VM_STATE_INTERPRET) {
2766 		if (tempFW != NULL) {
2767 			if (ficlWordIsCompileOnly(tempFW)) {
2768 				ficlVmThrowError(vm,
2769 				    "Error: FICL_VM_STATE_COMPILE only!");
2770 			}
2771 
2772 			ficlVmExecuteWord(vm, tempFW);
2773 			return (1); /* true */
2774 		}
2775 	} else {	/* (vm->state == FICL_VM_STATE_COMPILE) */
2776 		if (tempFW != NULL) {
2777 			if (ficlWordIsImmediate(tempFW)) {
2778 				ficlVmExecuteWord(vm, tempFW);
2779 			} else {
2780 				ficlCell c;
2781 				c.p = tempFW;
2782 				if (tempFW->flags & FICL_WORD_INSTRUCTION)
2783 					ficlDictionaryAppendUnsigned(dictionary,
2784 					    (ficlInteger)tempFW->code);
2785 				else
2786 					ficlDictionaryAppendCell(dictionary, c);
2787 			}
2788 			return (1); /* true */
2789 		}
2790 	}
2791 
2792 	return (0); /* false */
2793 }
2794