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1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
2 *
3 * ***** BEGIN LICENSE BLOCK *****
4 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
5 *
6 * The contents of this file are subject to the Mozilla Public License Version
7 * 1.1 (the "License"); you may not use this file except in compliance with
8 * the License. You may obtain a copy of the License at
9 * http://www.mozilla.org/MPL/
10 *
11 * Software distributed under the License is distributed on an "AS IS" basis,
12 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13 * for the specific language governing rights and limitations under the
14 * License.
15 *
16 * The Original Code is Mozilla Communicator client code, released
17 * March 31, 1998.
18 *
19 * The Initial Developer of the Original Code is
20 * Netscape Communications Corporation.
21 * Portions created by the Initial Developer are Copyright (C) 1998
22 * the Initial Developer. All Rights Reserved.
23 *
24 * Contributor(s):
25 *
26 * Alternatively, the contents of this file may be used under the terms of
27 * either of the GNU General Public License Version 2 or later (the "GPL"),
28 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
29 * in which case the provisions of the GPL or the LGPL are applicable instead
30 * of those above. If you wish to allow use of your version of this file only
31 * under the terms of either the GPL or the LGPL, and not to allow others to
32 * use your version of this file under the terms of the MPL, indicate your
33 * decision by deleting the provisions above and replace them with the notice
34 * and other provisions required by the GPL or the LGPL. If you do not delete
35 * the provisions above, a recipient may use your version of this file under
36 * the terms of any one of the MPL, the GPL or the LGPL.
37 *
38 * ***** END LICENSE BLOCK ***** */
40 /*
41 * JS bytecode descriptors, disassemblers, and decompilers.
42 */
43 #include "jsstddef.h"
44 #ifdef HAVE_MEMORY_H
45 #include <memory.h>
46 #endif
47 #include <stdarg.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include "jstypes.h"
52 #include "jsarena.h" /* Added by JSIFY */
53 #include "jsutil.h" /* Added by JSIFY */
54 #include "jsdtoa.h"
55 #include "jsprf.h"
56 #include "jsapi.h"
57 #include "jsarray.h"
58 #include "jsatom.h"
59 #include "jscntxt.h"
60 #include "jsconfig.h"
61 #include "jsdbgapi.h"
62 #include "jsemit.h"
63 #include "jsfun.h"
64 #include "jslock.h"
65 #include "jsobj.h"
66 #include "jsopcode.h"
67 #include "jsscope.h"
68 #include "jsscript.h"
69 #include "jsstr.h"
71 const char js_const_str[] = "const";
72 const char js_var_str[] = "var";
73 const char js_function_str[] = "function";
74 const char js_in_str[] = "in";
75 const char js_instanceof_str[] = "instanceof";
76 const char js_new_str[] = "new";
77 const char js_delete_str[] = "delete";
78 const char js_typeof_str[] = "typeof";
79 const char js_void_str[] = "void";
80 const char js_null_str[] = "null";
81 const char js_this_str[] = "this";
82 const char js_false_str[] = "false";
83 const char js_true_str[] = "true";
85 const char *js_incop_str[] = {"++", "--"};
87 /* Pollute the namespace locally for MSVC Win16, but not for WatCom. */
88 #ifdef __WINDOWS_386__
89 #ifdef FAR
90 #undef FAR
91 #endif
92 #else /* !__WINDOWS_386__ */
93 #ifndef FAR
94 #define FAR
95 #endif
96 #endif /* !__WINDOWS_386__ */
98 const JSCodeSpec FAR js_CodeSpec[] = {
99 #define OPDEF(op,val,name,token,length,nuses,ndefs,prec,format) \
100 {name,token,length,nuses,ndefs,prec,format},
101 #include "jsopcode.tbl"
102 #undef OPDEF
103 };
105 uintN js_NumCodeSpecs = sizeof (js_CodeSpec) / sizeof js_CodeSpec[0];
107 /************************************************************************/
109 static ptrdiff_t
110 GetJumpOffset(jsbytecode *pc, jsbytecode *pc2)
111 {
112 uint32 type;
114 type = (js_CodeSpec[*pc].format & JOF_TYPEMASK);
115 if (JOF_TYPE_IS_EXTENDED_JUMP(type))
116 return GET_JUMPX_OFFSET(pc2);
117 return GET_JUMP_OFFSET(pc2);
118 }
120 #ifdef DEBUG
122 JS_FRIEND_API(void)
123 js_Disassemble(JSContext *cx, JSScript *script, JSBool lines, FILE *fp)
124 {
125 jsbytecode *pc, *end;
126 uintN len;
128 pc = script->code;
129 end = pc + script->length;
130 while (pc < end) {
131 if (pc == script->main)
132 fputs("main:\n", fp);
133 len = js_Disassemble1(cx, script, pc,
134 PTRDIFF(pc, script->code, jsbytecode),
135 lines, fp);
136 if (!len)
137 return;
138 pc += len;
139 }
140 }
142 JS_FRIEND_API(uintN)
143 js_Disassemble1(JSContext *cx, JSScript *script, jsbytecode *pc, uintN loc,
144 JSBool lines, FILE *fp)
145 {
146 JSOp op;
147 const JSCodeSpec *cs;
148 intN len, off;
149 JSAtom *atom;
150 JSString *str;
151 char *cstr;
153 op = (JSOp)*pc;
154 if (op >= JSOP_LIMIT) {
155 char numBuf1[12], numBuf2[12];
156 JS_snprintf(numBuf1, sizeof numBuf1, "%d", op);
157 JS_snprintf(numBuf2, sizeof numBuf2, "%d", JSOP_LIMIT);
158 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
159 JSMSG_BYTECODE_TOO_BIG, numBuf1, numBuf2);
160 return 0;
161 }
162 cs = &js_CodeSpec[op];
163 len = (intN)cs->length;
164 fprintf(fp, "%05u:", loc);
165 if (lines)
166 fprintf(fp, "%4u", JS_PCToLineNumber(cx, script, pc));
167 fprintf(fp, " %s", cs->name);
168 switch (cs->format & JOF_TYPEMASK) {
169 case JOF_BYTE:
170 if (op == JSOP_TRAP) {
171 op = JS_GetTrapOpcode(cx, script, pc);
172 if (op == JSOP_LIMIT)
173 return 0;
174 len = (intN)js_CodeSpec[op].length;
175 }
176 break;
178 case JOF_JUMP:
179 case JOF_JUMPX:
180 off = GetJumpOffset(pc, pc);
181 fprintf(fp, " %u (%d)", loc + off, off);
182 break;
184 case JOF_CONST:
185 atom = GET_ATOM(cx, script, pc);
186 str = js_ValueToSource(cx, ATOM_KEY(atom));
187 if (!str)
188 return 0;
189 cstr = js_DeflateString(cx, JSSTRING_CHARS(str), JSSTRING_LENGTH(str));
190 if (!cstr)
191 return 0;
192 fprintf(fp, " %s", cstr);
193 JS_free(cx, cstr);
194 break;
196 case JOF_UINT16:
197 fprintf(fp, " %u", GET_ARGC(pc));
198 break;
200 #if JS_HAS_SWITCH_STATEMENT
201 case JOF_TABLESWITCH:
202 {
203 jsbytecode *pc2;
204 jsint i, low, high;
206 pc2 = pc;
207 off = GetJumpOffset(pc, pc2);
208 pc2 += JUMP_OFFSET_LEN;
209 low = GetJumpOffset(pc, pc2);
210 pc2 += JUMP_OFFSET_LEN;
211 high = GetJumpOffset(pc, pc2);
212 pc2 += JUMP_OFFSET_LEN;
213 fprintf(fp, " defaultOffset %d low %d high %d", off, low, high);
214 for (i = low; i <= high; i++) {
215 off = GetJumpOffset(pc, pc2);
216 fprintf(fp, "\n\t%d: %d", i, off);
217 pc2 += JUMP_OFFSET_LEN;
218 }
219 len = 1 + pc2 - pc;
220 break;
221 }
223 case JOF_LOOKUPSWITCH:
224 {
225 jsbytecode *pc2;
226 jsint npairs;
228 pc2 = pc;
229 off = GetJumpOffset(pc, pc2);
230 pc2 += JUMP_OFFSET_LEN;
231 npairs = (jsint) GET_ATOM_INDEX(pc2);
232 pc2 += ATOM_INDEX_LEN;
233 fprintf(fp, " offset %d npairs %u", off, (uintN) npairs);
234 while (npairs) {
235 atom = GET_ATOM(cx, script, pc2);
236 pc2 += ATOM_INDEX_LEN;
237 off = GetJumpOffset(pc, pc2);
238 pc2 += JUMP_OFFSET_LEN;
240 str = js_ValueToSource(cx, ATOM_KEY(atom));
241 if (!str)
242 return 0;
243 cstr = js_DeflateString(cx, JSSTRING_CHARS(str),
244 JSSTRING_LENGTH(str));
245 if (!cstr)
246 return 0;
247 fprintf(fp, "\n\t%s: %d", cstr, off);
248 JS_free(cx, cstr);
249 npairs--;
250 }
251 len = 1 + pc2 - pc;
252 break;
253 }
254 #endif /* JS_HAS_SWITCH_STATEMENT */
256 case JOF_QARG:
257 fprintf(fp, " %u", GET_ARGNO(pc));
258 break;
260 case JOF_QVAR:
261 fprintf(fp, " %u", GET_VARNO(pc));
262 break;
264 #if JS_HAS_LEXICAL_CLOSURE
265 case JOF_DEFLOCALVAR:
266 fprintf(fp, " %u", GET_VARNO(pc));
267 pc += VARNO_LEN;
268 atom = GET_ATOM(cx, script, pc);
269 str = js_ValueToSource(cx, ATOM_KEY(atom));
270 if (!str)
271 return 0;
272 cstr = js_DeflateString(cx, JSSTRING_CHARS(str), JSSTRING_LENGTH(str));
273 if (!cstr)
274 return 0;
275 fprintf(fp, " %s", cstr);
276 JS_free(cx, cstr);
277 break;
278 #endif
280 default: {
281 char numBuf[12];
282 JS_snprintf(numBuf, sizeof numBuf, "%lx", (unsigned long) cs->format);
283 JS_ReportErrorNumber(cx, js_GetErrorMessage, NULL,
284 JSMSG_UNKNOWN_FORMAT, numBuf);
285 return 0;
286 }
287 }
288 fputs("\n", fp);
289 return len;
290 }
292 #endif /* DEBUG */
294 /************************************************************************/
296 /*
297 * Sprintf, but with unlimited and automatically allocated buffering.
298 */
299 typedef struct Sprinter {
300 JSContext *context; /* context executing the decompiler */
301 JSArenaPool *pool; /* string allocation pool */
302 char *base; /* base address of buffer in pool */
303 size_t size; /* size of buffer allocated at base */
304 ptrdiff_t offset; /* offset of next free char in buffer */
305 } Sprinter;
307 #define INIT_SPRINTER(cx, sp, ap, off) \
308 ((sp)->context = cx, (sp)->pool = ap, (sp)->base = NULL, (sp)->size = 0, \
309 (sp)->offset = off)
311 #define OFF2STR(sp,off) ((sp)->base + (off))
312 #define STR2OFF(sp,str) ((str) - (sp)->base)
313 #define RETRACT(sp,str) ((sp)->offset = STR2OFF(sp, str))
315 static JSBool
316 SprintAlloc(Sprinter *sp, size_t nb)
317 {
318 if (!sp->base) {
319 JS_ARENA_ALLOCATE_CAST(sp->base, char *, sp->pool, nb);
320 } else {
321 JS_ARENA_GROW_CAST(sp->base, char *, sp->pool, sp->size, nb);
322 }
323 if (!sp->base) {
324 JS_ReportOutOfMemory(sp->context);
325 return JS_FALSE;
326 }
327 sp->size += nb;
328 return JS_TRUE;
329 }
331 static ptrdiff_t
332 SprintPut(Sprinter *sp, const char *s, size_t len)
333 {
334 ptrdiff_t nb, offset;
335 char *bp;
337 /* Allocate space for s, including the '\0' at the end. */
338 nb = (sp->offset + len + 1) - sp->size;
339 if (nb > 0 && !SprintAlloc(sp, nb))
340 return -1;
342 /* Advance offset and copy s into sp's buffer. */
343 offset = sp->offset;
344 sp->offset += len;
345 bp = sp->base + offset;
346 memmove(bp, s, len);
347 bp[len] = 0;
348 return offset;
349 }
351 static ptrdiff_t
352 Sprint(Sprinter *sp, const char *format, ...)
353 {
354 va_list ap;
355 char *bp;
356 ptrdiff_t offset;
358 va_start(ap, format);
359 bp = JS_vsmprintf(format, ap); /* XXX vsaprintf */
360 va_end(ap);
361 if (!bp) {
362 JS_ReportOutOfMemory(sp->context);
363 return -1;
364 }
365 offset = SprintPut(sp, bp, strlen(bp));
366 free(bp);
367 return offset;
368 }
370 const jschar js_EscapeMap[] = {
371 '\b', 'b',
372 '\f', 'f',
373 '\n', 'n',
374 '\r', 'r',
375 '\t', 't',
376 '\v', 'v',
377 '"', '"',
378 '\'', '\'',
379 '\\', '\\',
380 0
381 };
383 static char *
384 QuoteString(Sprinter *sp, JSString *str, jschar quote)
385 {
386 ptrdiff_t off, len, nb;
387 const jschar *s, *t, *u, *z;
388 char *bp;
389 jschar c;
390 JSBool ok;
392 /* Sample off first for later return value pointer computation. */
393 off = sp->offset;
394 if (quote && Sprint(sp, "%c", (char)quote) < 0)
395 return NULL;
397 /* Loop control variables: z points at end of string sentinel. */
398 s = JSSTRING_CHARS(str);
399 z = s + JSSTRING_LENGTH(str);
400 for (t = s; t < z; s = ++t) {
401 /* Move t forward from s past un-quote-worthy characters. */
402 c = *t;
403 while (JS_ISPRINT(c) && c != quote && c != '\\' && !(c >> 8)) {
404 c = *++t;
405 if (t == z)
406 break;
407 }
408 len = PTRDIFF(t, s, jschar);
410 /* Allocate space for s, including the '\0' at the end. */
411 nb = (sp->offset + len + 1) - sp->size;
412 if (nb > 0 && !SprintAlloc(sp, nb))
413 return NULL;
415 /* Advance sp->offset and copy s into sp's buffer. */
416 bp = sp->base + sp->offset;
417 sp->offset += len;
418 while (--len >= 0)
419 *bp++ = (char) *s++;
420 *bp = '\0';
422 if (t == z)
423 break;
425 /* Use js_EscapeMap, \u, or \x only if necessary. */
426 if ((u = js_strchr(js_EscapeMap, c)) != NULL)
427 ok = Sprint(sp, "\\%c", (char)u[1]) >= 0;
428 else
429 ok = Sprint(sp, (c >> 8) ? "\\u%04X" : "\\x%02X", c) >= 0;
430 if (!ok)
431 return NULL;
432 }
434 /* Sprint the closing quote and return the quoted string. */
435 if (quote && Sprint(sp, "%c", (char)quote) < 0)
436 return NULL;
437 return OFF2STR(sp, off);
438 }
440 JSString *
441 js_QuoteString(JSContext *cx, JSString *str, jschar quote)
442 {
443 void *mark;
444 Sprinter sprinter;
445 char *bytes;
446 JSString *escstr;
448 mark = JS_ARENA_MARK(&cx->tempPool);
449 INIT_SPRINTER(cx, &sprinter, &cx->tempPool, 0);
450 bytes = QuoteString(&sprinter, str, quote);
451 escstr = bytes ? JS_NewStringCopyZ(cx, bytes) : NULL;
452 JS_ARENA_RELEASE(&cx->tempPool, mark);
453 return escstr;
454 }
456 /************************************************************************/
458 struct JSPrinter {
459 Sprinter sprinter; /* base class state */
460 JSArenaPool pool; /* string allocation pool */
461 uintN indent; /* indentation in spaces */
462 JSBool pretty; /* pretty-print: indent, use newlines */
463 JSScript *script; /* script being printed */
464 JSScope *scope; /* script function scope */
465 };
467 JSPrinter *
468 js_NewPrinter(JSContext *cx, const char *name, uintN indent, JSBool pretty)
469 {
470 JSPrinter *jp;
471 JSStackFrame *fp;
472 JSObjectMap *map;
474 jp = (JSPrinter *) JS_malloc(cx, sizeof(JSPrinter));
475 if (!jp)
476 return NULL;
477 INIT_SPRINTER(cx, &jp->sprinter, &jp->pool, 0);
478 JS_InitArenaPool(&jp->pool, name, 256, 1);
479 jp->indent = indent;
480 jp->pretty = pretty;
481 jp->script = NULL;
482 jp->scope = NULL;
483 fp = cx->fp;
484 if (fp && fp->fun && fp->fun->object) {
485 map = fp->fun->object->map;
486 if (MAP_IS_NATIVE(map))
487 jp->scope = (JSScope *)map;
488 }
489 return jp;
490 }
492 void
493 js_DestroyPrinter(JSPrinter *jp)
494 {
495 JS_FinishArenaPool(&jp->pool);
496 JS_free(jp->sprinter.context, jp);
497 }
499 JSString *
500 js_GetPrinterOutput(JSPrinter *jp)
501 {
502 JSContext *cx;
503 JSString *str;
505 cx = jp->sprinter.context;
506 if (!jp->sprinter.base)
507 return cx->runtime->emptyString;
508 str = JS_NewStringCopyZ(cx, jp->sprinter.base);
509 if (!str)
510 return NULL;
511 JS_FreeArenaPool(&jp->pool);
512 INIT_SPRINTER(cx, &jp->sprinter, &jp->pool, 0);
513 return str;
514 }
516 int
517 js_printf(JSPrinter *jp, const char *format, ...)
518 {
519 va_list ap;
520 char *bp, *fp;
521 int cc;
523 if (*format == '\0')
524 return 0;
526 va_start(ap, format);
528 /* If pretty-printing, expand magic tab into a run of jp->indent spaces. */
529 if (*format == '\t') {
530 if (jp->pretty && Sprint(&jp->sprinter, "%*s", jp->indent, "") < 0)
531 return -1;
532 format++;
533 }
535 /* Suppress newlines (must be once per format, at the end) if not pretty. */
536 fp = NULL;
537 if (!jp->pretty && format[cc = strlen(format)-1] == '\n') {
538 fp = JS_strdup(jp->sprinter.context, format);
539 if (!fp)
540 return -1;
541 fp[cc] = '\0';
542 format = fp;
543 }
545 /* Allocate temp space, convert format, and put. */
546 bp = JS_vsmprintf(format, ap); /* XXX vsaprintf */
547 if (fp) {
548 JS_free(jp->sprinter.context, fp);
549 format = NULL;
550 }
551 if (!bp) {
552 JS_ReportOutOfMemory(jp->sprinter.context);
553 return -1;
554 }
556 cc = strlen(bp);
557 if (SprintPut(&jp->sprinter, bp, (size_t)cc) < 0)
558 cc = -1;
559 free(bp);
561 va_end(ap);
562 return cc;
563 }
565 JSBool
566 js_puts(JSPrinter *jp, const char *s)
567 {
568 return SprintPut(&jp->sprinter, s, strlen(s)) >= 0;
569 }
571 /************************************************************************/
573 typedef struct SprintStack {
574 Sprinter sprinter; /* sprinter for postfix to infix buffering */
575 ptrdiff_t *offsets; /* stack of postfix string offsets */
576 jsbytecode *opcodes; /* parallel stack of JS opcodes */
577 uintN top; /* top of stack index */
578 JSPrinter *printer; /* permanent output goes here */
579 } SprintStack;
581 /* Gap between stacked strings to allow for insertion of parens and commas. */
582 #define PAREN_SLOP (2 + 1)
584 /*
585 * These pseudo-ops help js_DecompileValueGenerator decompile JSOP_SETNAME,
586 * JSOP_SETPROP, and JSOP_SETELEM, respectively. See the first assertion in
587 * PushOff.
588 */
589 #define JSOP_GETPROP2 254
590 #define JSOP_GETELEM2 255
592 static JSBool
593 PushOff(SprintStack *ss, ptrdiff_t off, JSOp op)
594 {
595 uintN top;
597 #if JSOP_LIMIT > JSOP_GETPROP2
598 #error JSOP_LIMIT must be <= JSOP_GETPROP2
599 #endif
600 if (!SprintAlloc(&ss->sprinter, PAREN_SLOP))
601 return JS_FALSE;
603 /* ss->top points to the next free slot; be paranoid about overflow. */
604 top = ss->top;
605 JS_ASSERT(top < ss->printer->script->depth);
606 if (top >= ss->printer->script->depth) {
607 JS_ReportOutOfMemory(ss->sprinter.context);
608 return JS_FALSE;
609 }
611 /* The opcodes stack must contain real bytecodes that index js_CodeSpec. */
612 ss->offsets[top] = off;
613 ss->opcodes[top] = (op == JSOP_GETPROP2) ? JSOP_GETPROP
614 : (op == JSOP_GETELEM2) ? JSOP_GETELEM
615 : (jsbytecode) op;
616 ss->top = ++top;
617 ss->sprinter.offset += PAREN_SLOP;
618 return JS_TRUE;
619 }
621 static ptrdiff_t
622 PopOff(SprintStack *ss, JSOp op)
623 {
624 uintN top;
625 const JSCodeSpec *cs, *topcs;
626 ptrdiff_t off;
628 /* ss->top points to the next free slot; be paranoid about underflow. */
629 top = ss->top;
630 JS_ASSERT(top != 0);
631 if (top == 0)
632 return 0;
634 ss->top = --top;
635 topcs = &js_CodeSpec[ss->opcodes[top]];
636 cs = &js_CodeSpec[op];
637 if (topcs->prec != 0 && topcs->prec < cs->prec) {
638 ss->offsets[top] -= 2;
639 ss->sprinter.offset = ss->offsets[top];
640 off = Sprint(&ss->sprinter, "(%s)",
641 OFF2STR(&ss->sprinter, ss->sprinter.offset + 2));
642 } else {
643 off = ss->sprinter.offset = ss->offsets[top];
644 }
645 return off;
646 }
648 #if JS_HAS_SWITCH_STATEMENT
649 typedef struct TableEntry {
650 jsval key;
651 ptrdiff_t offset;
652 } TableEntry;
654 static int
655 CompareOffsets(const void *v1, const void *v2, void *arg)
656 {
657 const TableEntry *te1 = (const TableEntry *) v1,
658 *te2 = (const TableEntry *) v2;
660 return te1->offset - te2->offset;
661 }
663 static JSBool
664 Decompile(SprintStack *ss, jsbytecode *pc, intN nb);
666 static JSBool
667 DecompileSwitch(SprintStack *ss, TableEntry *table, uintN tableLength,
668 jsbytecode *pc, ptrdiff_t switchLength,
669 ptrdiff_t defaultOffset, JSBool isCondSwitch)
670 {
671 JSContext *cx;
672 JSPrinter *jp;
673 char *lval, *rval;
674 uintN i;
675 ptrdiff_t diff, off, off2, caseExprOff;
676 jsval key;
677 JSString *str;
679 cx = ss->sprinter.context;
680 jp = ss->printer;
682 lval = OFF2STR(&ss->sprinter, PopOff(ss, JSOP_NOP));
683 js_printf(jp, "\tswitch (%s) {\n", lval);
685 if (tableLength) {
686 diff = table[0].offset - defaultOffset;
687 if (diff > 0) {
688 jp->indent += 2;
689 js_printf(jp, "\tdefault:\n");
690 jp->indent += 2;
691 if (!Decompile(ss, pc + defaultOffset, diff))
692 return JS_FALSE;
693 jp->indent -= 4;
694 }
696 caseExprOff = isCondSwitch
697 ? (ptrdiff_t) js_CodeSpec[JSOP_CONDSWITCH].length
698 : 0;
700 for (i = 0; i < tableLength; i++) {
701 off = table[i].offset;
702 if (i + 1 < tableLength)
703 off2 = table[i + 1].offset;
704 else
705 off2 = switchLength;
707 key = table[i].key;
708 if (isCondSwitch) {
709 ptrdiff_t nextCaseExprOff;
711 /*
712 * key encodes the JSOP_CASE bytecode's offset from switchtop.
713 * The next case expression follows immediately, unless we are
714 * at the last case.
715 */
716 nextCaseExprOff = (ptrdiff_t)JSVAL_TO_INT(key);
717 nextCaseExprOff += js_CodeSpec[pc[nextCaseExprOff]].length;
718 jp->indent += 2;
719 if (!Decompile(ss, pc + caseExprOff,
720 nextCaseExprOff - caseExprOff)) {
721 return JS_FALSE;
722 }
723 caseExprOff = nextCaseExprOff;
724 } else {
725 /*
726 * key comes from an atom, not the decompiler, so we need to
727 * quote it if it's a string literal.
728 */
729 str = js_ValueToString(cx, key);
730 if (!str)
731 return JS_FALSE;
732 jp->indent += 2;
733 if (JSVAL_IS_STRING(key)) {
734 rval = QuoteString(&ss->sprinter, str, (jschar)'"');
735 if (!rval)
736 return JS_FALSE;
737 RETRACT(&ss->sprinter, rval);
738 } else {
739 rval = JS_GetStringBytes(str);
740 }
741 js_printf(jp, "\tcase %s:\n", rval);
742 }
744 jp->indent += 2;
745 if (off <= defaultOffset && defaultOffset < off2) {
746 diff = defaultOffset - off;
747 if (diff != 0) {
748 if (!Decompile(ss, pc + off, diff))
749 return JS_FALSE;
750 off = defaultOffset;
751 }
752 jp->indent -= 2;
753 js_printf(jp, "\tdefault:\n");
754 jp->indent += 2;
755 }
756 if (!Decompile(ss, pc + off, off2 - off))
757 return JS_FALSE;
758 jp->indent -= 4;
759 }
760 }
762 if (defaultOffset == switchLength) {
763 jp->indent += 2;
764 js_printf(jp, "\tdefault:\n");
765 jp->indent -= 2;
766 }
767 js_printf(jp, "\t}\n");
768 return JS_TRUE;
769 }
770 #endif
772 static JSAtom *
773 GetSlotAtom(JSPrinter *jp, JSPropertyOp getter, uintN slot)
774 {
775 JSScope *scope;
776 JSScopeProperty *sprop;
777 JSObject *obj, *proto;
779 scope = jp->scope;
780 while (scope) {
781 for (sprop = SCOPE_LAST_PROP(scope); sprop; sprop = sprop->parent) {
782 if (sprop->getter != getter)
783 continue;
784 JS_ASSERT(sprop->flags & SPROP_HAS_SHORTID);
785 JS_ASSERT(!JSVAL_IS_INT(sprop->id));
786 if ((uintN) sprop->shortid == slot)
787 return (JSAtom *) sprop->id;
788 }
789 obj = scope->object;
790 if (!obj)
791 break;
792 proto = OBJ_GET_PROTO(jp->sprinter.context, obj);
793 if (!proto)
794 break;
795 scope = OBJ_SCOPE(proto);
796 }
797 return NULL;
798 }
800 static const char *
801 VarPrefix(jssrcnote *sn)
802 {
803 const char *kw;
804 static char buf[8];
806 kw = NULL;
807 if (sn) {
808 if (SN_TYPE(sn) == SRC_VAR)
809 kw = js_var_str;
810 else if (SN_TYPE(sn) == SRC_CONST)
811 kw = js_const_str;
812 }
813 if (!kw)
814 return "";
815 JS_snprintf(buf, sizeof buf, "%s ", kw);
816 return buf;
817 }
819 static JSBool
820 Decompile(SprintStack *ss, jsbytecode *pc, intN nb)
821 {
822 JSContext *cx;
823 JSPrinter *jp, *jp2;
824 jsbytecode *endpc, *done, *forelem_tail, *forelem_done;
825 ptrdiff_t len, todo, oplen, cond, next, tail;
826 JSOp op, lastop, saveop;
827 const JSCodeSpec *cs, *topcs;
828 jssrcnote *sn, *sn2;
829 const char *lval, *rval, *xval, *fmt;
830 jsint i, argc;
831 char **argv;
832 JSAtom *atom;
833 JSObject *obj;
834 JSFunction *fun;
835 JSString *str;
836 JSBool ok;
837 jsval val;
839 /*
840 * Local macros
841 */
842 #define DECOMPILE_CODE(pc,nb) if (!Decompile(ss, pc, nb)) return JS_FALSE
843 #define POP_STR() OFF2STR(&ss->sprinter, PopOff(ss, op))
844 #define LOCAL_ASSERT(expr) JS_ASSERT(expr); if (!(expr)) return JS_FALSE
846 /*
847 * Get atom from script's atom map, quote/escape its string appropriately into
848 * rval, and select fmt from the quoted and unquoted alternatives.
849 */
850 #define GET_ATOM_QUOTE_AND_FMT(qfmt, ufmt, rval) \
851 JS_BEGIN_MACRO \
852 jschar quote_; \
853 atom = GET_ATOM(cx, jp->script, pc); \
854 if (ATOM_KEYWORD(atom)) { \
855 quote_ = '\''; \
856 fmt = qfmt; \
857 } else { \
858 quote_ = 0; \
859 fmt = ufmt; \
860 } \
861 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), quote_); \
862 if (!rval) \
863 return JS_FALSE; \
864 JS_END_MACRO
866 cx = ss->sprinter.context;
867 jp = ss->printer;
868 endpc = pc + nb;
869 forelem_tail = forelem_done = NULL;
870 todo = -2; /* NB: different from Sprint() error return. */
871 tail = -1;
872 op = JSOP_NOP;
873 sn = NULL;
874 rval = NULL;
876 while (pc < endpc) {
877 lastop = op;
878 op = saveop = (JSOp) *pc;
879 if (op >= JSOP_LIMIT) {
880 switch (op) {
881 case JSOP_GETPROP2:
882 saveop = JSOP_GETPROP;
883 break;
884 case JSOP_GETELEM2:
885 saveop = JSOP_GETELEM;
886 break;
887 default:;
888 }
889 }
890 cs = &js_CodeSpec[saveop];
891 len = oplen = cs->length;
893 if (cs->token) {
894 switch (cs->nuses) {
895 case 2:
896 rval = POP_STR();
897 lval = POP_STR();
898 sn = js_GetSrcNote(jp->script, pc);
899 if (sn && SN_TYPE(sn) == SRC_ASSIGNOP) {
900 /* Print only the right operand of the assignment-op. */
901 todo = SprintPut(&ss->sprinter, rval, strlen(rval));
902 } else {
903 todo = Sprint(&ss->sprinter, "%s %s %s",
904 lval, cs->token, rval);
905 }
906 break;
908 case 1:
909 rval = POP_STR();
910 todo = Sprint(&ss->sprinter, "%s%s", cs->token, rval);
911 break;
913 case 0:
914 #if JS_HAS_GETTER_SETTER
915 if (op == JSOP_GETTER || op == JSOP_SETTER) {
916 todo = -2;
917 break;
918 }
919 #endif
920 todo = SprintPut(&ss->sprinter, cs->token, strlen(cs->token));
921 break;
923 default:
924 todo = -2;
925 break;
926 }
927 } else {
928 switch (op) {
929 case JSOP_NOP:
930 /*
931 * Check for a do-while loop, a for-loop with an empty
932 * initializer part, a labeled statement, a function
933 * definition, or try/finally.
934 */
935 sn = js_GetSrcNote(jp->script, pc);
936 todo = -2;
937 switch (sn ? SN_TYPE(sn) : SRC_NULL) {
938 #if JS_HAS_DO_WHILE_LOOP
939 case SRC_WHILE:
940 js_printf(jp, "\tdo {\n");
941 jp->indent += 4;
942 break;
943 #endif /* JS_HAS_DO_WHILE_LOOP */
945 case SRC_FOR:
946 rval = "";
948 do_forloop:
949 /* Skip the JSOP_NOP or JSOP_POP bytecode. */
950 pc++;
952 /* Get the cond, next, and loop-closing tail offsets. */
953 cond = js_GetSrcNoteOffset(sn, 0);
954 next = js_GetSrcNoteOffset(sn, 1);
955 tail = js_GetSrcNoteOffset(sn, 2);
956 LOCAL_ASSERT(tail + GetJumpOffset(pc+tail, pc+tail) == 0);
958 /* Print the keyword and the possibly empty init-part. */
959 js_printf(jp, "\tfor (%s;", rval);
961 if (pc[cond] == JSOP_IFEQ || pc[cond] == JSOP_IFEQX) {
962 /* Decompile the loop condition. */
963 DECOMPILE_CODE(pc, cond);
964 js_printf(jp, " %s", POP_STR());
965 }
967 /* Need a semicolon whether or not there was a cond. */
968 js_puts(jp, ";");
970 if (pc[next] != JSOP_GOTO && pc[next] != JSOP_GOTOX) {
971 /* Decompile the loop updater. */
972 DECOMPILE_CODE(pc + next, tail - next - 1);
973 js_printf(jp, " %s", POP_STR());
974 }
976 /* Do the loop body. */
977 js_puts(jp, ") {\n");
978 jp->indent += 4;
979 oplen = (cond) ? js_CodeSpec[pc[cond]].length : 0;
980 DECOMPILE_CODE(pc + cond + oplen, next - cond - oplen);
981 jp->indent -= 4;
982 js_printf(jp, "\t}\n");
984 /* Set len so pc skips over the entire loop. */
985 len = tail + js_CodeSpec[pc[tail]].length;
986 break;
988 case SRC_LABEL:
989 atom = js_GetAtom(cx, &jp->script->atomMap,
990 (jsatomid) js_GetSrcNoteOffset(sn, 0));
991 jp->indent -= 4;
992 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
993 if (!rval)
994 return JS_FALSE;
995 RETRACT(&ss->sprinter, rval);
996 js_printf(jp, "\t%s:\n", rval);
997 jp->indent += 4;
998 break;
1000 case SRC_LABELBRACE:
1001 atom = js_GetAtom(cx, &jp->script->atomMap,
1002 (jsatomid) js_GetSrcNoteOffset(sn, 0));
1003 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1004 if (!rval)
1005 return JS_FALSE;
1006 RETRACT(&ss->sprinter, rval);
1007 js_printf(jp, "\t%s: {\n", rval);
1008 jp->indent += 4;
1009 break;
1011 case SRC_ENDBRACE:
1012 jp->indent -= 4;
1013 js_printf(jp, "\t}\n");
1014 break;
1016 case SRC_CATCH:
1017 jp->indent -= 4;
1018 sn = js_GetSrcNote(jp->script, pc);
1019 pc += oplen;
1020 js_printf(jp, "\t} catch (");
1022 LOCAL_ASSERT(*pc == JSOP_NAME);
1023 pc += js_CodeSpec[JSOP_NAME].length;
1024 LOCAL_ASSERT(*pc == JSOP_PUSHOBJ);
1025 pc += js_CodeSpec[JSOP_PUSHOBJ].length;
1026 LOCAL_ASSERT(*pc == JSOP_NEWINIT);
1027 pc += js_CodeSpec[JSOP_NEWINIT].length;
1028 LOCAL_ASSERT(*pc == JSOP_EXCEPTION);
1029 pc += js_CodeSpec[JSOP_EXCEPTION].length;
1030 LOCAL_ASSERT(*pc == JSOP_INITCATCHVAR);
1031 atom = GET_ATOM(cx, jp->script, pc);
1032 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1033 if (!rval)
1034 return JS_FALSE;
1035 RETRACT(&ss->sprinter, rval);
1036 js_printf(jp, "%s", rval);
1037 pc += js_CodeSpec[JSOP_INITCATCHVAR].length;
1038 LOCAL_ASSERT(*pc == JSOP_ENTERWITH);
1039 pc += js_CodeSpec[JSOP_ENTERWITH].length;
1041 len = js_GetSrcNoteOffset(sn, 0);
1042 if (len) {
1043 js_printf(jp, " if ");
1044 DECOMPILE_CODE(pc, len);
1045 js_printf(jp, "%s", POP_STR());
1046 pc += len;
1047 LOCAL_ASSERT(*pc == JSOP_IFEQ || *pc == JSOP_IFEQX);
1048 pc += js_CodeSpec[*pc].length;
1049 }
1051 js_printf(jp, ") {\n");
1052 jp->indent += 4;
1053 len = 0;
1054 break;
1056 case SRC_FUNCDEF:
1057 atom = js_GetAtom(cx, &jp->script->atomMap,
1058 (jsatomid) js_GetSrcNoteOffset(sn, 0));
1059 JS_ASSERT(ATOM_IS_OBJECT(atom));
1060 do_function:
1061 obj = ATOM_TO_OBJECT(atom);
1062 fun = (JSFunction *) JS_GetPrivate(cx, obj);
1063 jp2 = js_NewPrinter(cx, JS_GetFunctionName(fun),
1064 jp->indent, jp->pretty);
1065 if (!jp2)
1066 return JS_FALSE;
1067 jp2->scope = jp->scope;
1068 if (js_DecompileFunction(jp2, fun)) {
1069 str = js_GetPrinterOutput(jp2);
1070 if (str)
1071 js_printf(jp, "%s\n", JS_GetStringBytes(str));
1072 }
1073 js_DestroyPrinter(jp2);
1074 break;
1076 default:;
1077 }
1078 case JSOP_RETRVAL:
1079 break;
1081 case JSOP_GROUP:
1082 /* Use last real op so PopOff adds parens if needed. */
1083 todo = PopOff(ss, lastop);
1085 /* Now add user-supplied parens only if PopOff did not. */
1086 cs = &js_CodeSpec[lastop];
1087 topcs = &js_CodeSpec[ss->opcodes[ss->top]];
1088 if (topcs->prec >= cs->prec) {
1089 todo = Sprint(&ss->sprinter, "(%s)",
1090 OFF2STR(&ss->sprinter, todo));
1091 }
1092 break;
1094 case JSOP_PUSH:
1095 case JSOP_PUSHOBJ:
1096 case JSOP_BINDNAME:
1097 todo = Sprint(&ss->sprinter, "");
1098 break;
1100 #if JS_HAS_EXCEPTIONS
1101 case JSOP_TRY:
1102 js_printf(jp, "\ttry {\n");
1103 jp->indent += 4;
1104 todo = -2;
1105 break;
1107 {
1108 static const char finally_cookie[] = "finally-cookie";
1110 case JSOP_FINALLY:
1111 jp->indent -= 4;
1112 js_printf(jp, "\t} finally {\n");
1113 jp->indent += 4;
1115 /*
1116 * We must push an empty string placeholder for gosub's return
1117 * address, popped by JSOP_RETSUB and counted by script->depth
1118 * but not by ss->top (see JSOP_SETSP, below).
1119 */
1120 todo = Sprint(&ss->sprinter, finally_cookie);
1121 break;
1123 case JSOP_RETSUB:
1124 rval = POP_STR();
1125 LOCAL_ASSERT(strcmp(rval, finally_cookie) == 0);
1126 todo = -2;
1127 break;
1128 }
1130 case JSOP_SWAP:
1131 /*
1132 * We don't generate this opcode currently, and previously we
1133 * did not need to decompile it. If old, serialized bytecode
1134 * uses it still, we should fall through and set todo = -2.
1135 */
1136 /* FALL THROUGH */
1138 case JSOP_GOSUB:
1139 case JSOP_GOSUBX:
1140 /*
1141 * JSOP_GOSUB and GOSUBX have no effect on the decompiler's
1142 * string stack because the next op in bytecode order finds
1143 * the stack balanced by a JSOP_RETSUB executed elsewhere.
1144 */
1145 todo = -2;
1146 break;
1148 case JSOP_SETSP:
1149 /*
1150 * The compiler models operand stack depth and fixes the stack
1151 * pointer on entry to a catch clause based on its depth model.
1152 * The decompiler must match the code generator's model, which
1153 * is why JSOP_FINALLY pushes a cookie that JSOP_RETSUB pops.
1154 */
1155 ss->top = (uintN) GET_ATOM_INDEX(pc);
1156 break;
1158 case JSOP_EXCEPTION:
1159 /*
1160 * The only other JSOP_EXCEPTION case occurs as part of a code
1161 * sequence that follows a SRC_CATCH-annotated JSOP_NOP.
1162 */
1163 sn = js_GetSrcNote(jp->script, pc);
1164 LOCAL_ASSERT(sn && SN_TYPE(sn) == SRC_HIDDEN);
1165 todo = -2;
1166 break;
1167 #endif /* JS_HAS_EXCEPTIONS */
1169 case JSOP_POP:
1170 case JSOP_POPV:
1171 sn = js_GetSrcNote(jp->script, pc);
1172 switch (sn ? SN_TYPE(sn) : SRC_NULL) {
1173 case SRC_FOR:
1174 rval = POP_STR();
1175 todo = -2;
1176 goto do_forloop;
1178 case SRC_PCDELTA:
1179 /* Pop and save to avoid blowing stack depth budget. */
1180 lval = JS_strdup(cx, POP_STR());
1181 if (!lval)
1182 return JS_FALSE;
1184 /*
1185 * The offset tells distance to the end of the right-hand
1186 * operand of the comma operator.
1187 */
1188 done = pc + len;
1189 pc += js_GetSrcNoteOffset(sn, 0);
1190 len = 0;
1192 if (!Decompile(ss, done, pc - done)) {
1193 JS_free(cx, (char *)lval);
1194 return JS_FALSE;
1195 }
1197 /* Pop Decompile result and print comma expression. */
1198 rval = POP_STR();
1199 todo = Sprint(&ss->sprinter, "%s, %s", lval, rval);
1200 JS_free(cx, (char *)lval);
1201 break;
1203 case SRC_HIDDEN:
1204 /* Hide this pop, it's from a goto in a with or for/in. */
1205 todo = -2;
1206 break;
1208 default:
1209 rval = POP_STR();
1210 if (*rval != '\0')
1211 js_printf(jp, "\t%s;\n", rval);
1212 todo = -2;
1213 break;
1214 }
1215 break;
1217 case JSOP_POP2:
1218 (void) PopOff(ss, op);
1219 (void) PopOff(ss, op);
1220 todo = -2;
1221 break;
1223 {
1224 static const char with_cookie[] = "with-cookie";
1226 case JSOP_ENTERWITH:
1227 sn = js_GetSrcNote(jp->script, pc);
1228 if (sn && SN_TYPE(sn) == SRC_HIDDEN) {
1229 todo = -2;
1230 break;
1231 }
1232 rval = POP_STR();
1233 js_printf(jp, "\twith (%s) {\n", rval);
1234 jp->indent += 4;
1235 todo = Sprint(&ss->sprinter, with_cookie);
1236 break;
1238 case JSOP_LEAVEWITH:
1239 sn = js_GetSrcNote(jp->script, pc);
1240 todo = -2;
1241 if (sn && SN_TYPE(sn) == SRC_HIDDEN)
1242 break;
1243 rval = POP_STR();
1244 LOCAL_ASSERT(strcmp(rval, with_cookie) == 0);
1245 jp->indent -= 4;
1246 js_printf(jp, "\t}\n");
1247 break;
1248 }
1250 case JSOP_SETRVAL:
1251 case JSOP_RETURN:
1252 rval = POP_STR();
1253 if (*rval != '\0')
1254 js_printf(jp, "\t%s %s;\n", cs->name, rval);
1255 else
1256 js_printf(jp, "\t%s;\n", cs->name);
1257 todo = -2;
1258 break;
1260 #if JS_HAS_EXCEPTIONS
1261 case JSOP_THROW:
1262 sn = js_GetSrcNote(jp->script, pc);
1263 todo = -2;
1264 if (sn && SN_TYPE(sn) == SRC_HIDDEN)
1265 break;
1266 rval = POP_STR();
1267 js_printf(jp, "\t%s %s;\n", cs->name, rval);
1268 break;
1269 #endif /* JS_HAS_EXCEPTIONS */
1271 case JSOP_GOTO:
1272 case JSOP_GOTOX:
1273 sn = js_GetSrcNote(jp->script, pc);
1274 switch (sn ? SN_TYPE(sn) : SRC_NULL) {
1275 case SRC_CONT2LABEL:
1276 atom = js_GetAtom(cx, &jp->script->atomMap,
1277 (jsatomid) js_GetSrcNoteOffset(sn, 0));
1278 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1279 if (!rval)
1280 return JS_FALSE;
1281 RETRACT(&ss->sprinter, rval);
1282 js_printf(jp, "\tcontinue %s;\n", rval);
1283 break;
1284 case SRC_CONTINUE:
1285 js_printf(jp, "\tcontinue;\n");
1286 break;
1287 case SRC_BREAK2LABEL:
1288 atom = js_GetAtom(cx, &jp->script->atomMap,
1289 (jsatomid) js_GetSrcNoteOffset(sn, 0));
1290 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1291 if (!rval)
1292 return JS_FALSE;
1293 RETRACT(&ss->sprinter, rval);
1294 js_printf(jp, "\tbreak %s;\n", rval);
1295 break;
1296 case SRC_HIDDEN:
1297 break;
1298 default:
1299 js_printf(jp, "\tbreak;\n");
1300 break;
1301 }
1302 todo = -2;
1303 break;
1305 case JSOP_IFEQ:
1306 case JSOP_IFEQX:
1307 len = GetJumpOffset(pc, pc);
1308 sn = js_GetSrcNote(jp->script, pc);
1310 switch (sn ? SN_TYPE(sn) : SRC_NULL) {
1311 case SRC_IF:
1312 case SRC_IF_ELSE:
1313 rval = POP_STR();
1314 js_printf(jp, "\tif (%s) {\n", rval);
1315 jp->indent += 4;
1316 if (SN_TYPE(sn) == SRC_IF) {
1317 DECOMPILE_CODE(pc + oplen, len - oplen);
1318 } else {
1319 len = js_GetSrcNoteOffset(sn, 0);
1320 DECOMPILE_CODE(pc + oplen, len - oplen);
1321 jp->indent -= 4;
1322 pc += len;
1323 LOCAL_ASSERT(*pc == JSOP_GOTO || *pc == JSOP_GOTOX);
1324 oplen = js_CodeSpec[*pc].length;
1325 len = GetJumpOffset(pc, pc);
1326 js_printf(jp, "\t} else {\n");
1327 jp->indent += 4;
1328 DECOMPILE_CODE(pc + oplen, len - oplen);
1329 }
1330 jp->indent -= 4;
1331 js_printf(jp, "\t}\n");
1332 todo = -2;
1333 break;
1335 case SRC_WHILE:
1336 rval = POP_STR();
1337 js_printf(jp, "\twhile (%s) {\n", rval);
1338 jp->indent += 4;
1339 tail = js_GetSrcNoteOffset(sn, 0);
1340 DECOMPILE_CODE(pc + oplen, tail - oplen);
1341 jp->indent -= 4;
1342 js_printf(jp, "\t}\n");
1343 todo = -2;
1344 break;
1346 case SRC_COND:
1347 xval = JS_strdup(cx, POP_STR());
1348 if (!xval)
1349 return JS_FALSE;
1350 len = js_GetSrcNoteOffset(sn, 0);
1351 DECOMPILE_CODE(pc + oplen, len - oplen);
1352 lval = JS_strdup(cx, POP_STR());
1353 if (!lval) {
1354 JS_free(cx, (void *)xval);
1355 return JS_FALSE;
1356 }
1357 pc += len;
1358 LOCAL_ASSERT(*pc == JSOP_GOTO || *pc == JSOP_GOTOX);
1359 oplen = js_CodeSpec[*pc].length;
1360 len = GetJumpOffset(pc, pc);
1361 DECOMPILE_CODE(pc + oplen, len - oplen);
1362 rval = POP_STR();
1363 todo = Sprint(&ss->sprinter, "%s ? %s : %s",
1364 xval, lval, rval);
1365 JS_free(cx, (void *)xval);
1366 JS_free(cx, (void *)lval);
1367 break;
1369 default:
1370 break;
1371 }
1372 break;
1374 case JSOP_IFNE:
1375 case JSOP_IFNEX:
1376 #if JS_HAS_DO_WHILE_LOOP
1377 /* Currently, this must be a do-while loop's upward branch. */
1378 jp->indent -= 4;
1379 js_printf(jp, "\t} while (%s);\n", POP_STR());
1380 todo = -2;
1381 #else
1382 JS_ASSERT(0);
1383 #endif /* JS_HAS_DO_WHILE_LOOP */
1384 break;
1386 case JSOP_OR:
1387 case JSOP_ORX:
1388 xval = "||";
1390 do_logical_connective:
1391 /* Top of stack is the first clause in a disjunction (||). */
1392 lval = JS_strdup(cx, POP_STR());
1393 if (!lval)
1394 return JS_FALSE;
1395 done = pc + GetJumpOffset(pc, pc);
1396 pc += len;
1397 len = PTRDIFF(done, pc, jsbytecode);
1398 DECOMPILE_CODE(pc, len);
1399 rval = POP_STR();
1400 if (jp->pretty &&
1401 jp->indent + 4 + strlen(lval) + 4 + strlen(rval) > 75) {
1402 rval = JS_strdup(cx, rval);
1403 if (!rval) {
1404 tail = -1;
1405 } else {
1406 todo = Sprint(&ss->sprinter, "%s %s\n", lval, xval);
1407 tail = Sprint(&ss->sprinter, "%*s%s",
1408 jp->indent + 4, "", rval);
1409 JS_free(cx, (char *)rval);
1410 }
1411 if (tail < 0)
1412 todo = -1;
1413 } else {
1414 todo = Sprint(&ss->sprinter, "%s %s %s", lval, xval, rval);
1415 }
1416 JS_free(cx, (char *)lval);
1417 break;
1419 case JSOP_AND:
1420 case JSOP_ANDX:
1421 xval = "&&";
1422 goto do_logical_connective;
1424 case JSOP_FORARG:
1425 atom = GetSlotAtom(jp, js_GetArgument, GET_ARGNO(pc));
1426 LOCAL_ASSERT(atom);
1427 goto do_fornameinloop;
1429 case JSOP_FORVAR:
1430 atom = GetSlotAtom(jp, js_GetLocalVariable, GET_VARNO(pc));
1431 LOCAL_ASSERT(atom);
1432 goto do_fornameinloop;
1434 case JSOP_FORNAME:
1435 atom = GET_ATOM(cx, jp->script, pc);
1437 do_fornameinloop:
1438 sn = js_GetSrcNote(jp->script, pc);
1439 xval = NULL;
1440 lval = "";
1441 goto do_forinloop;
1443 case JSOP_FORPROP:
1444 xval = NULL;
1445 atom = GET_ATOM(cx, jp->script, pc);
1446 if (ATOM_KEYWORD(atom)) {
1447 xval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom),
1448 (jschar)'\'');
1449 if (!xval)
1450 return JS_FALSE;
1451 atom = NULL;
1452 }
1453 lval = POP_STR();
1454 sn = NULL;
1456 do_forinloop:
1457 pc += oplen;
1458 LOCAL_ASSERT(*pc == JSOP_IFEQ || *pc == JSOP_IFEQX);
1459 oplen = js_CodeSpec[*pc].length;
1460 len = GetJumpOffset(pc, pc);
1461 sn2 = js_GetSrcNote(jp->script, pc);
1462 tail = js_GetSrcNoteOffset(sn2, 0);
1464 do_forinbody:
1465 js_printf(jp, "\tfor (%s%s", VarPrefix(sn), lval);
1466 if (atom) {
1467 xval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1468 if (!xval)
1469 return JS_FALSE;
1470 RETRACT(&ss->sprinter, xval);
1471 js_printf(jp, *lval ? ".%s" : "%s", xval);
1472 } else if (xval) {
1473 js_printf(jp, "[%s]", xval);
1474 }
1475 rval = OFF2STR(&ss->sprinter, ss->offsets[ss->top-1]);
1476 js_printf(jp, " in %s) {\n", rval);
1477 jp->indent += 4;
1478 DECOMPILE_CODE(pc + oplen, tail - oplen);
1479 jp->indent -= 4;
1480 js_printf(jp, "\t}\n");
1481 todo = -2;
1482 break;
1484 case JSOP_FORELEM:
1485 pc++;
1486 LOCAL_ASSERT(*pc == JSOP_IFEQ || *pc == JSOP_IFEQX);
1487 len = js_CodeSpec[*pc].length;
1489 /*
1490 * Arrange for the JSOP_ENUMELEM case to set tail for use by
1491 * do_forinbody: code that uses on it to find the loop-closing
1492 * jump (whatever its format, normal or extended), in order to
1493 * bound the recursively decompiled loop body.
1494 */
1495 sn = js_GetSrcNote(jp->script, pc);
1496 JS_ASSERT(!forelem_tail);
1497 forelem_tail = pc + js_GetSrcNoteOffset(sn, 0);
1499 /*
1500 * This gets a little wacky. Only the length of the for loop
1501 * body PLUS the element-indexing expression is known here, so
1502 * we pass the after-loop pc to the JSOP_ENUMELEM case, which
1503 * is immediately below, to decompile that helper bytecode via
1504 * the 'forelem_done' local.
1505 *
1506 * Since a for..in loop can't nest in the head of another for
1507 * loop, we can use forelem_{tail,done} singletons to remember
1508 * state from JSOP_FORELEM to JSOP_ENUMELEM, thence (via goto)
1509 * to label do_forinbody.
1510 */
1511 JS_ASSERT(!forelem_done);
1512 forelem_done = pc + GetJumpOffset(pc, pc);
1513 break;
1515 case JSOP_ENUMELEM:
1516 /*
1517 * The stack has the object under the (top) index expression.
1518 * The "rval" property id is underneath those two on the stack.
1519 * The for loop body net and gross lengths can now be adjusted
1520 * to account for the length of the indexing expression that
1521 * came after JSOP_FORELEM and before JSOP_ENUMELEM.
1522 */
1523 atom = NULL;
1524 xval = POP_STR();
1525 lval = POP_STR();
1526 rval = OFF2STR(&ss->sprinter, ss->offsets[ss->top-1]);
1527 JS_ASSERT(forelem_tail > pc);
1528 tail = forelem_tail - pc;
1529 forelem_tail = NULL;
1530 JS_ASSERT(forelem_done > pc);
1531 len = forelem_done - pc;
1532 forelem_done = NULL;
1533 goto do_forinbody;
1535 case JSOP_DUP2:
1536 rval = OFF2STR(&ss->sprinter, ss->offsets[ss->top-2]);
1537 todo = SprintPut(&ss->sprinter, rval, strlen(rval));
1538 if (todo < 0 || !PushOff(ss, todo, ss->opcodes[ss->top-2]))
1539 return JS_FALSE;
1540 /* FALL THROUGH */
1542 case JSOP_DUP:
1543 rval = OFF2STR(&ss->sprinter, ss->offsets[ss->top-1]);
1544 op = ss->opcodes[ss->top-1];
1545 todo = SprintPut(&ss->sprinter, rval, strlen(rval));
1546 break;
1548 case JSOP_SETARG:
1549 atom = GetSlotAtom(jp, js_GetArgument, GET_ARGNO(pc));
1550 LOCAL_ASSERT(atom);
1551 goto do_setname;
1553 case JSOP_SETVAR:
1554 atom = GetSlotAtom(jp, js_GetLocalVariable, GET_VARNO(pc));
1555 LOCAL_ASSERT(atom);
1556 goto do_setname;
1558 case JSOP_SETCONST:
1559 case JSOP_SETNAME:
1560 atom = GET_ATOM(cx, jp->script, pc);
1561 do_setname:
1562 lval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1563 if (!lval)
1564 return JS_FALSE;
1565 rval = POP_STR();
1566 if (op == JSOP_SETNAME)
1567 (void) PopOff(ss, op);
1568 do_setlval:
1569 sn = js_GetSrcNote(jp->script, pc - 1);
1570 if (sn && SN_TYPE(sn) == SRC_ASSIGNOP) {
1571 todo = Sprint(&ss->sprinter, "%s %s= %s",
1572 lval, js_CodeSpec[lastop].token, rval);
1573 } else {
1574 sn = js_GetSrcNote(jp->script, pc);
1575 todo = Sprint(&ss->sprinter, "%s%s = %s",
1576 VarPrefix(sn), lval, rval);
1577 }
1578 break;
1580 case JSOP_NEW:
1581 case JSOP_CALL:
1582 case JSOP_EVAL:
1583 #if JS_HAS_LVALUE_RETURN
1584 case JSOP_SETCALL:
1585 #endif
1586 saveop = op;
1587 op = JSOP_NOP; /* turn off parens */
1588 argc = GET_ARGC(pc);
1589 argv = (char **)
1590 JS_malloc(cx, (size_t)(argc + 1) * sizeof *argv);
1591 if (!argv)
1592 return JS_FALSE;
1594 ok = JS_TRUE;
1595 for (i = argc; i > 0; i--) {
1596 argv[i] = JS_strdup(cx, POP_STR());
1597 if (!argv[i]) {
1598 ok = JS_FALSE;
1599 break;
1600 }
1601 }
1603 /* Skip the JSOP_PUSHOBJ-created empty string. */
1604 LOCAL_ASSERT(ss->top >= 2);
1605 (void) PopOff(ss, op);
1607 /* Get the callee's decompiled image in argv[0]. */
1608 argv[0] = JS_strdup(cx, POP_STR());
1609 if (!argv[i])
1610 ok = JS_FALSE;
1612 lval = "(", rval = ")";
1613 if (saveop == JSOP_NEW) {
1614 todo = Sprint(&ss->sprinter, "%s %s%s",
1615 js_new_str, argv[0], lval);
1616 } else {
1617 todo = Sprint(&ss->sprinter, "%s%s",
1618 argv[0], lval);
1619 }
1620 if (todo < 0)
1621 ok = JS_FALSE;
1623 for (i = 1; i <= argc; i++) {
1624 if (!argv[i] ||
1625 Sprint(&ss->sprinter, "%s%s",
1626 argv[i], (i < argc) ? ", " : "") < 0) {
1627 ok = JS_FALSE;
1628 break;
1629 }
1630 }
1631 if (Sprint(&ss->sprinter, rval) < 0)
1632 ok = JS_FALSE;
1634 for (i = 0; i <= argc; i++) {
1635 if (argv[i])
1636 JS_free(cx, argv[i]);
1637 }
1638 JS_free(cx, argv);
1639 if (!ok)
1640 return JS_FALSE;
1641 op = saveop;
1642 #if JS_HAS_LVALUE_RETURN
1643 if (op == JSOP_SETCALL) {
1644 if (!PushOff(ss, todo, op))
1645 return JS_FALSE;
1646 todo = Sprint(&ss->sprinter, "");
1647 }
1648 #endif
1649 break;
1651 case JSOP_DELNAME:
1652 atom = GET_ATOM(cx, jp->script, pc);
1653 lval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1654 if (!lval)
1655 return JS_FALSE;
1656 RETRACT(&ss->sprinter, lval);
1657 todo = Sprint(&ss->sprinter, "%s %s", js_delete_str, lval);
1658 break;
1660 case JSOP_DELPROP:
1661 GET_ATOM_QUOTE_AND_FMT("%s %s[%s]", "%s %s.%s", rval);
1662 lval = POP_STR();
1663 todo = Sprint(&ss->sprinter, fmt, js_delete_str, lval, rval);
1664 break;
1666 case JSOP_DELELEM:
1667 xval = POP_STR();
1668 lval = POP_STR();
1669 todo = Sprint(&ss->sprinter, "%s %s[%s]",
1670 js_delete_str, lval, xval);
1671 break;
1673 case JSOP_TYPEOF:
1674 case JSOP_VOID:
1675 rval = POP_STR();
1676 todo = Sprint(&ss->sprinter, "%s %s", cs->name, rval);
1677 break;
1679 case JSOP_INCARG:
1680 case JSOP_DECARG:
1681 atom = GetSlotAtom(jp, js_GetArgument, GET_ARGNO(pc));
1682 LOCAL_ASSERT(atom);
1683 goto do_incatom;
1685 case JSOP_INCVAR:
1686 case JSOP_DECVAR:
1687 atom = GetSlotAtom(jp, js_GetLocalVariable, GET_VARNO(pc));
1688 LOCAL_ASSERT(atom);
1689 goto do_incatom;
1691 case JSOP_INCNAME:
1692 case JSOP_DECNAME:
1693 atom = GET_ATOM(cx, jp->script, pc);
1694 do_incatom:
1695 lval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1696 if (!lval)
1697 return JS_FALSE;
1698 RETRACT(&ss->sprinter, lval);
1699 todo = Sprint(&ss->sprinter, "%s%s",
1700 js_incop_str[!(cs->format & JOF_INC)], lval);
1701 break;
1703 case JSOP_INCPROP:
1704 case JSOP_DECPROP:
1705 GET_ATOM_QUOTE_AND_FMT("%s%s[%s]", "%s%s.%s", rval);
1706 lval = POP_STR();
1707 todo = Sprint(&ss->sprinter, fmt,
1708 js_incop_str[!(cs->format & JOF_INC)],
1709 lval, rval);
1710 break;
1712 case JSOP_INCELEM:
1713 case JSOP_DECELEM:
1714 xval = POP_STR();
1715 lval = POP_STR();
1716 todo = Sprint(&ss->sprinter, "%s%s[%s]",
1717 js_incop_str[!(cs->format & JOF_INC)],
1718 lval, xval);
1719 break;
1721 case JSOP_ARGINC:
1722 case JSOP_ARGDEC:
1723 atom = GetSlotAtom(jp, js_GetArgument, GET_ARGNO(pc));
1724 LOCAL_ASSERT(atom);
1725 goto do_atominc;
1727 case JSOP_VARINC:
1728 case JSOP_VARDEC:
1729 atom = GetSlotAtom(jp, js_GetLocalVariable, GET_VARNO(pc));
1730 LOCAL_ASSERT(atom);
1731 goto do_atominc;
1733 case JSOP_NAMEINC:
1734 case JSOP_NAMEDEC:
1735 atom = GET_ATOM(cx, jp->script, pc);
1736 do_atominc:
1737 lval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1738 if (!lval)
1739 return JS_FALSE;
1740 todo = STR2OFF(&ss->sprinter, lval);
1741 SprintPut(&ss->sprinter,
1742 js_incop_str[!(cs->format & JOF_INC)],
1743 2);
1744 break;
1746 case JSOP_PROPINC:
1747 case JSOP_PROPDEC:
1748 GET_ATOM_QUOTE_AND_FMT("%s[%s]%s", "%s.%s%s", rval);
1749 lval = POP_STR();
1750 todo = Sprint(&ss->sprinter, fmt, lval, rval,
1751 js_incop_str[!(cs->format & JOF_INC)]);
1752 break;
1754 case JSOP_ELEMINC:
1755 case JSOP_ELEMDEC:
1756 xval = POP_STR();
1757 lval = POP_STR();
1758 todo = Sprint(&ss->sprinter, "%s[%s]%s",
1759 lval, xval,
1760 js_incop_str[!(cs->format & JOF_INC)]);
1761 break;
1763 case JSOP_GETPROP2:
1764 op = JSOP_GETPROP;
1765 (void) PopOff(ss, lastop);
1766 /* FALL THROUGH */
1768 case JSOP_GETPROP:
1769 GET_ATOM_QUOTE_AND_FMT("%s[%s]", "%s.%s", rval);
1770 lval = POP_STR();
1771 todo = Sprint(&ss->sprinter, fmt, lval, rval);
1772 break;
1774 case JSOP_SETPROP:
1775 GET_ATOM_QUOTE_AND_FMT("%s[%s] %s= %s", "%s.%s %s= %s", xval);
1776 rval = POP_STR();
1777 lval = POP_STR();
1778 sn = js_GetSrcNote(jp->script, pc - 1);
1779 todo = Sprint(&ss->sprinter, fmt, lval, xval,
1780 (sn && SN_TYPE(sn) == SRC_ASSIGNOP)
1781 ? js_CodeSpec[lastop].token
1782 : "",
1783 rval);
1784 break;
1786 case JSOP_GETELEM2:
1787 op = JSOP_GETELEM;
1788 (void) PopOff(ss, lastop);
1789 /* FALL THROUGH */
1791 case JSOP_GETELEM:
1792 op = JSOP_NOP; /* turn off parens */
1793 xval = POP_STR();
1794 op = JSOP_GETELEM;
1795 lval = POP_STR();
1796 if (*xval == '\0')
1797 todo = Sprint(&ss->sprinter, "%s", lval);
1798 else
1799 todo = Sprint(&ss->sprinter, "%s[%s]", lval, xval);
1800 break;
1802 case JSOP_SETELEM:
1803 op = JSOP_NOP; /* turn off parens */
1804 rval = POP_STR();
1805 xval = POP_STR();
1806 op = JSOP_SETELEM;
1807 lval = POP_STR();
1808 if (*xval == '\0')
1809 goto do_setlval;
1810 sn = js_GetSrcNote(jp->script, pc - 1);
1811 todo = Sprint(&ss->sprinter, "%s[%s] %s= %s",
1812 lval, xval,
1813 (sn && SN_TYPE(sn) == SRC_ASSIGNOP)
1814 ? js_CodeSpec[lastop].token
1815 : "",
1816 rval);
1817 break;
1819 case JSOP_ARGSUB:
1820 i = (jsint) GET_ATOM_INDEX(pc);
1821 todo = Sprint(&ss->sprinter, "%s[%d]",
1822 js_arguments_str, (int) i);
1823 break;
1825 case JSOP_ARGCNT:
1826 todo = Sprint(&ss->sprinter, "%s.%s",
1827 js_arguments_str, js_length_str);
1828 break;
1830 case JSOP_GETARG:
1831 atom = GetSlotAtom(jp, js_GetArgument, GET_ARGNO(pc));
1832 LOCAL_ASSERT(atom);
1833 goto do_name;
1835 case JSOP_GETVAR:
1836 atom = GetSlotAtom(jp, js_GetLocalVariable, GET_VARNO(pc));
1837 LOCAL_ASSERT(atom);
1838 goto do_name;
1840 case JSOP_NAME:
1841 atom = GET_ATOM(cx, jp->script, pc);
1842 do_name:
1843 sn = js_GetSrcNote(jp->script, pc);
1844 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
1845 if (!rval)
1846 return JS_FALSE;
1847 RETRACT(&ss->sprinter, rval);
1848 todo = Sprint(&ss->sprinter, "%s%s", VarPrefix(sn), rval);
1849 break;
1851 case JSOP_UINT16:
1852 i = (jsint) GET_ATOM_INDEX(pc);
1853 todo = Sprint(&ss->sprinter, "%u", (unsigned) i);
1854 break;
1856 case JSOP_NUMBER:
1857 atom = GET_ATOM(cx, jp->script, pc);
1858 val = ATOM_KEY(atom);
1859 if (JSVAL_IS_INT(val)) {
1860 long ival = (long)JSVAL_TO_INT(val);
1861 todo = Sprint(&ss->sprinter, "%ld", ival);
1862 } else {
1863 char buf[DTOSTR_STANDARD_BUFFER_SIZE];
1864 char *numStr = JS_dtostr(buf, sizeof buf, DTOSTR_STANDARD,
1865 0, *JSVAL_TO_DOUBLE(val));
1866 if (!numStr) {
1867 JS_ReportOutOfMemory(cx);
1868 return JS_FALSE;
1869 }
1870 todo = Sprint(&ss->sprinter, numStr);
1871 }
1872 break;
1874 case JSOP_STRING:
1875 atom = GET_ATOM(cx, jp->script, pc);
1876 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom),
1877 (jschar)'"');
1878 if (!rval)
1879 return JS_FALSE;
1880 todo = STR2OFF(&ss->sprinter, rval);
1881 break;
1883 case JSOP_OBJECT:
1884 case JSOP_ANONFUNOBJ:
1885 case JSOP_NAMEDFUNOBJ:
1886 atom = GET_ATOM(cx, jp->script, pc);
1887 if (op == JSOP_OBJECT) {
1888 str = js_ValueToSource(cx, ATOM_KEY(atom));
1889 if (!str)
1890 return JS_FALSE;
1891 } else {
1892 if (!js_fun_toString(cx, ATOM_TO_OBJECT(atom),
1893 JS_DONT_PRETTY_PRINT, 0, NULL,
1894 &val)) {
1895 return JS_FALSE;
1896 }
1897 str = JSVAL_TO_STRING(val);
1898 }
1899 todo = SprintPut(&ss->sprinter, JS_GetStringBytes(str),
1900 JSSTRING_LENGTH(str));
1901 break;
1903 #if JS_HAS_SWITCH_STATEMENT
1904 case JSOP_TABLESWITCH:
1905 case JSOP_TABLESWITCHX:
1906 {
1907 jsbytecode *pc2;
1908 ptrdiff_t off, off2;
1909 jsint j, n, low, high;
1910 TableEntry *table;
1912 sn = js_GetSrcNote(jp->script, pc);
1913 JS_ASSERT(sn && SN_TYPE(sn) == SRC_SWITCH);
1914 len = js_GetSrcNoteOffset(sn, 0);
1915 pc2 = pc;
1916 off = GetJumpOffset(pc, pc2);
1917 pc2 += JUMP_OFFSET_LEN;
1918 low = GetJumpOffset(pc, pc2);
1919 pc2 += JUMP_OFFSET_LEN;
1920 high = GetJumpOffset(pc, pc2);
1922 n = high - low + 1;
1923 if (n == 0) {
1924 table = NULL;
1925 j = 0;
1926 } else {
1927 table = (TableEntry *)
1928 JS_malloc(cx, (size_t)n * sizeof *table);
1929 if (!table)
1930 return JS_FALSE;
1931 for (i = j = 0; i < n; i++) {
1932 pc2 += JUMP_OFFSET_LEN;
1933 off2 = GetJumpOffset(pc, pc2);
1934 if (off2) {
1935 table[j].key = INT_TO_JSVAL(low + i);
1936 table[j++].offset = off2;
1937 }
1938 }
1939 js_HeapSort(table, (size_t) j, sizeof *table,
1940 CompareOffsets, NULL);
1941 }
1943 ok = DecompileSwitch(ss, table, (uintN)j, pc, len, off,
1944 JS_FALSE);
1945 JS_free(cx, table);
1946 if (!ok)
1947 return ok;
1948 todo = -2;
1949 break;
1950 }
1952 case JSOP_LOOKUPSWITCH:
1953 case JSOP_LOOKUPSWITCHX:
1954 {
1955 jsbytecode *pc2;
1956 ptrdiff_t off, off2;
1957 jsint npairs;
1958 TableEntry *table;
1960 sn = js_GetSrcNote(jp->script, pc);
1961 JS_ASSERT(sn && SN_TYPE(sn) == SRC_SWITCH);
1962 len = js_GetSrcNoteOffset(sn, 0);
1963 pc2 = pc;
1964 off = GetJumpOffset(pc, pc2);
1965 pc2 += JUMP_OFFSET_LEN;
1966 npairs = (jsint) GET_ATOM_INDEX(pc2);
1967 pc2 += ATOM_INDEX_LEN;
1969 table = (TableEntry *)
1970 JS_malloc(cx, (size_t)npairs * sizeof *table);
1971 if (!table)
1972 return JS_FALSE;
1973 for (i = 0; i < npairs; i++) {
1974 atom = GET_ATOM(cx, jp->script, pc2);
1975 pc2 += ATOM_INDEX_LEN;
1976 off2 = GetJumpOffset(pc, pc2);
1977 pc2 += JUMP_OFFSET_LEN;
1978 table[i].key = ATOM_KEY(atom);
1979 table[i].offset = off2;
1980 }
1982 ok = DecompileSwitch(ss, table, (uintN)npairs, pc, len, off,
1983 JS_FALSE);
1984 JS_free(cx, table);
1985 if (!ok)
1986 return ok;
1987 todo = -2;
1988 break;
1989 }
1991 case JSOP_CONDSWITCH:
1992 {
1993 jsbytecode *pc2;
1994 ptrdiff_t off, off2, caseOff;
1995 jsint ncases;
1996 TableEntry *table;
1998 sn = js_GetSrcNote(jp->script, pc);
1999 JS_ASSERT(sn && SN_TYPE(sn) == SRC_SWITCH);
2000 len = js_GetSrcNoteOffset(sn, 0);
2001 off = js_GetSrcNoteOffset(sn, 1);
2003 /*
2004 * Count the cases using offsets from switch to first case,
2005 * and case to case, stored in srcnote immediates.
2006 */
2007 pc2 = pc;
2008 off2 = off;
2009 for (ncases = 0; off2 != 0; ncases++) {
2010 pc2 += off2;
2011 JS_ASSERT(*pc2 == JSOP_CASE || *pc2 == JSOP_DEFAULT ||
2012 *pc2 == JSOP_CASEX || *pc2 == JSOP_DEFAULTX);
2013 if (*pc2 == JSOP_DEFAULT || *pc2 == JSOP_DEFAULTX) {
2014 /* End of cases, but count default as a case. */
2015 off2 = 0;
2016 } else {
2017 sn = js_GetSrcNote(jp->script, pc2);
2018 JS_ASSERT(sn && SN_TYPE(sn) == SRC_PCDELTA);
2019 off2 = js_GetSrcNoteOffset(sn, 0);
2020 }
2021 }
2023 /*
2024 * Allocate table and rescan the cases using their srcnotes,
2025 * stashing each case's delta from switch top in table[i].key,
2026 * and the distance to its statements in table[i].offset.
2027 */
2028 table = (TableEntry *)
2029 JS_malloc(cx, (size_t)ncases * sizeof *table);
2030 if (!table)
2031 return JS_FALSE;
2032 pc2 = pc;
2033 off2 = off;
2034 for (i = 0; i < ncases; i++) {
2035 pc2 += off2;
2036 JS_ASSERT(*pc2 == JSOP_CASE || *pc2 == JSOP_DEFAULT ||
2037 *pc2 == JSOP_CASEX || *pc2 == JSOP_DEFAULTX);
2038 caseOff = pc2 - pc;
2039 table[i].key = INT_TO_JSVAL((jsint) caseOff);
2040 table[i].offset = caseOff + GetJumpOffset(pc2, pc2);
2041 if (*pc2 == JSOP_CASE || *pc2 == JSOP_CASEX) {
2042 sn = js_GetSrcNote(jp->script, pc2);
2043 JS_ASSERT(sn && SN_TYPE(sn) == SRC_PCDELTA);
2044 off2 = js_GetSrcNoteOffset(sn, 0);
2045 }
2046 }
2048 /*
2049 * Find offset of default code by fetching the default offset
2050 * from the end of table. JSOP_CONDSWITCH always has a default
2051 * case at the end.
2052 */
2053 off = JSVAL_TO_INT(table[ncases-1].key);
2054 pc2 = pc + off;
2055 off += GetJumpOffset(pc2, pc2);
2057 ok = DecompileSwitch(ss, table, (uintN)ncases, pc, len, off,
2058 JS_TRUE);
2059 JS_free(cx, table);
2060 if (!ok)
2061 return ok;
2062 todo = -2;
2063 break;
2064 }
2066 case JSOP_CASE:
2067 case JSOP_CASEX:
2068 {
2069 lval = POP_STR();
2070 if (!lval)
2071 return JS_FALSE;
2072 js_printf(jp, "\tcase %s:\n", lval);
2073 todo = -2;
2074 break;
2075 }
2077 #endif /* JS_HAS_SWITCH_STATEMENT */
2079 #if !JS_BUG_FALLIBLE_EQOPS
2080 case JSOP_NEW_EQ:
2081 case JSOP_NEW_NE:
2082 rval = POP_STR();
2083 lval = POP_STR();
2084 todo = Sprint(&ss->sprinter, "%s %c%s %s",
2085 lval,
2086 (op == JSOP_NEW_EQ) ? '=' : '!',
2087 #if JS_HAS_TRIPLE_EQOPS
2088 JSVERSION_IS_ECMA(cx->version) ? "==" :
2089 #endif
2090 "=",
2091 rval);
2092 break;
2093 #endif /* !JS_BUG_FALLIBLE_EQOPS */
2095 #if JS_HAS_LEXICAL_CLOSURE
2096 case JSOP_CLOSURE:
2097 atom = GET_ATOM(cx, jp->script, pc);
2098 JS_ASSERT(ATOM_IS_OBJECT(atom));
2099 goto do_function;
2100 #endif /* JS_HAS_LEXICAL_CLOSURE */
2102 #if JS_HAS_EXPORT_IMPORT
2103 case JSOP_EXPORTALL:
2104 js_printf(jp, "\texport *\n");
2105 todo = -2;
2106 break;
2108 case JSOP_EXPORTNAME:
2109 atom = GET_ATOM(cx, jp->script, pc);
2110 rval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom), 0);
2111 if (!rval)
2112 return JS_FALSE;
2113 RETRACT(&ss->sprinter, rval);
2114 js_printf(jp, "\texport %s\n", rval);
2115 todo = -2;
2116 break;
2118 case JSOP_IMPORTALL:
2119 lval = POP_STR();
2120 js_printf(jp, "\timport %s.*\n", lval);
2121 todo = -2;
2122 break;
2124 case JSOP_IMPORTPROP:
2125 GET_ATOM_QUOTE_AND_FMT("\timport %s[%s]\n", "\timport %s.%s\n",
2126 rval);
2127 lval = POP_STR();
2128 js_printf(jp, fmt, lval, rval);
2129 todo = -2;
2130 break;
2132 case JSOP_IMPORTELEM:
2133 xval = POP_STR();
2134 op = JSOP_GETELEM;
2135 lval = POP_STR();
2136 js_printf(jp, "\timport %s[%s]\n", lval, xval);
2137 todo = -2;
2138 break;
2139 #endif /* JS_HAS_EXPORT_IMPORT */
2141 case JSOP_TRAP:
2142 op = JS_GetTrapOpcode(cx, jp->script, pc);
2143 if (op == JSOP_LIMIT)
2144 return JS_FALSE;
2145 *pc = op;
2146 cs = &js_CodeSpec[op];
2147 len = cs->length;
2148 DECOMPILE_CODE(pc, len);
2149 *pc = JSOP_TRAP;
2150 todo = -2;
2151 break;
2153 #if JS_HAS_INITIALIZERS
2154 case JSOP_NEWINIT:
2155 LOCAL_ASSERT(ss->top >= 2);
2156 (void) PopOff(ss, op);
2157 lval = POP_STR();
2158 #if JS_HAS_SHARP_VARS
2159 op = (JSOp)pc[len];
2160 if (op == JSOP_DEFSHARP) {
2161 pc += len;
2162 cs = &js_CodeSpec[op];
2163 len = cs->length;
2164 i = (jsint) GET_ATOM_INDEX(pc);
2165 todo = Sprint(&ss->sprinter, "#%u=%c",
2166 (unsigned) i,
2167 (*lval == 'O') ? '{' : '[');
2168 } else
2169 #endif /* JS_HAS_SHARP_VARS */
2170 {
2171 todo = Sprint(&ss->sprinter, (*lval == 'O') ? "{" : "[");
2172 }
2173 break;
2175 case JSOP_ENDINIT:
2176 rval = POP_STR();
2177 sn = js_GetSrcNote(jp->script, pc);
2178 todo = Sprint(&ss->sprinter, "%s%s%c",
2179 rval,
2180 (sn && SN_TYPE(sn) == SRC_CONTINUE) ? ", " : "",
2181 (*rval == '{') ? '}' : ']');
2182 break;
2184 case JSOP_INITPROP:
2185 case JSOP_INITCATCHVAR:
2186 atom = GET_ATOM(cx, jp->script, pc);
2187 xval = QuoteString(&ss->sprinter, ATOM_TO_STRING(atom),
2188 ATOM_KEYWORD(atom) ? '\'' : 0);
2189 if (!xval)
2190 return JS_FALSE;
2191 rval = POP_STR();
2192 lval = POP_STR();
2193 do_initprop:
2194 #ifdef OLD_GETTER_SETTER
2195 todo = Sprint(&ss->sprinter, "%s%s%s%s%s:%s",
2196 lval,
2197 (lval[1] != '\0') ? ", " : "",
2198 xval,
2199 (lastop == JSOP_GETTER || lastop == JSOP_SETTER)
2200 ? " " : "",
2201 (lastop == JSOP_GETTER) ? js_getter_str :
2202 (lastop == JSOP_SETTER) ? js_setter_str :
2203 "",
2204 rval);
2205 #else
2206 if (lastop == JSOP_GETTER || lastop == JSOP_SETTER) {
2207 todo = Sprint(&ss->sprinter, "%s%s%s %s%s",
2208 lval,
2209 (lval[1] != '\0') ? ", " : "",
2210 (lastop == JSOP_GETTER)
2211 ? js_get_str : js_set_str,
2212 xval,
2213 rval + strlen(js_function_str) + 1);
2214 } else {
2215 todo = Sprint(&ss->sprinter, "%s%s%s:%s",
2216 lval,
2217 (lval[1] != '\0') ? ", " : "",
2218 xval,
2219 rval);
2220 }
2221 #endif
2222 break;
2224 case JSOP_INITELEM:
2225 rval = POP_STR();
2226 xval = POP_STR();
2227 lval = POP_STR();
2228 sn = js_GetSrcNote(jp->script, pc);
2229 if (sn && SN_TYPE(sn) == SRC_LABEL)
2230 goto do_initprop;
2231 todo = Sprint(&ss->sprinter, "%s%s%s",
2232 lval,
2233 (lval[1] != '\0' || *xval != '0') ? ", " : "",
2234 rval);
2235 break;
2237 #if JS_HAS_SHARP_VARS
2238 case JSOP_DEFSHARP:
2239 i = (jsint) GET_ATOM_INDEX(pc);
2240 rval = POP_STR();
2241 todo = Sprint(&ss->sprinter, "#%u=%s", (unsigned) i, rval);
2242 break;
2244 case JSOP_USESHARP:
2245 i = (jsint) GET_ATOM_INDEX(pc);
2246 todo = Sprint(&ss->sprinter, "#%u#", (unsigned) i);
2247 break;
2248 #endif /* JS_HAS_SHARP_VARS */
2249 #endif /* JS_HAS_INITIALIZERS */
2251 #if JS_HAS_DEBUGGER_KEYWORD
2252 case JSOP_DEBUGGER:
2253 js_printf(jp, "\tdebugger;\n");
2254 todo = -2;
2255 break;
2256 #endif /* JS_HAS_DEBUGGER_KEYWORD */
2258 default:
2259 todo = -2;
2260 break;
2261 }
2262 }
2264 if (todo < 0) {
2265 /* -2 means "don't push", -1 means reported error. */
2266 if (todo == -1)
2267 return JS_FALSE;
2268 } else {
2269 if (!PushOff(ss, todo, op))
2270 return JS_FALSE;
2271 }
2272 pc += len;
2273 }
2275 /*
2276 * Undefine local macros.
2277 */
2278 #undef DECOMPILE_CODE
2279 #undef POP_STR
2280 #undef LOCAL_ASSERT
2281 #undef GET_ATOM_QUOTE_AND_FMT
2283 return JS_TRUE;
2284 }
2287 JSBool
2288 js_DecompileCode(JSPrinter *jp, JSScript *script, jsbytecode *pc, uintN len)
2289 {
2290 SprintStack ss;
2291 JSContext *cx;
2292 void *mark, *space;
2293 size_t offsetsz, opcodesz;
2294 JSBool ok;
2295 JSScript *oldscript;
2296 char *last;
2298 /* Initialize a sprinter for use with the offset stack. */
2299 ss.printer = jp;
2300 cx = jp->sprinter.context;
2301 mark = JS_ARENA_MARK(&cx->tempPool);
2302 INIT_SPRINTER(cx, &ss.sprinter, &cx->tempPool, PAREN_SLOP);
2304 /* Allocate the parallel (to avoid padding) offset and opcode stacks. */
2305 offsetsz = script->depth * sizeof(ptrdiff_t);
2306 opcodesz = script->depth * sizeof(jsbytecode);
2307 JS_ARENA_ALLOCATE(space, &cx->tempPool, offsetsz + opcodesz);
2308 if (!space) {
2309 ok = JS_FALSE;
2310 goto out;
2311 }
2312 ss.offsets = (ptrdiff_t *) space;
2313 ss.opcodes = (jsbytecode *) ((char *)space + offsetsz);
2314 ss.top = 0;
2316 /* Call recursive subroutine to do the hard work. */
2317 oldscript = jp->script;
2318 jp->script = script;
2319 ok = Decompile(&ss, pc, len);
2320 jp->script = oldscript;
2322 /* If the given code didn't empty the stack, do it now. */
2323 if (ss.top) {
2324 do {
2325 last = OFF2STR(&ss.sprinter, PopOff(&ss, JSOP_NOP));
2326 } while (ss.top);
2327 js_printf(jp, "%s", last);
2328 }
2330 out:
2331 /* Free all temporary stuff allocated under this call. */
2332 JS_ARENA_RELEASE(&cx->tempPool, mark);
2333 return ok;
2334 }
2336 JSBool
2337 js_DecompileScript(JSPrinter *jp, JSScript *script)
2338 {
2339 return js_DecompileCode(jp, script, script->code, (uintN)script->length);
2340 }
2342 static const char native_code_str[] = "\t[native code]\n";
2344 JSBool
2345 js_DecompileFunctionBody(JSPrinter *jp, JSFunction *fun)
2346 {
2347 JSScript *script;
2348 JSScope *scope, *save;
2349 JSBool ok;
2351 script = fun->script;
2352 if (!script) {
2353 js_printf(jp, native_code_str);
2354 return JS_TRUE;
2355 }
2356 scope = fun->object ? OBJ_SCOPE(fun->object) : NULL;
2357 save = jp->scope;
2358 jp->scope = scope;
2359 ok = js_DecompileCode(jp, script, script->code, (uintN)script->length);
2360 jp->scope = save;
2361 return ok;
2362 }
2364 JSBool
2365 js_DecompileFunction(JSPrinter *jp, JSFunction *fun)
2366 {
2367 JSContext *cx;
2368 uintN i, nargs, indent;
2369 void *mark;
2370 JSAtom **params;
2371 JSScope *scope, *oldscope;
2372 JSScopeProperty *sprop;
2373 JSBool ok;
2375 /*
2376 * If pretty, conform to ECMA-262 Edition 3, 15.3.4.2, by decompiling a
2377 * FunctionDeclaration. Otherwise, check the JSFUN_LAMBDA flag and force
2378 * an expression by parenthesizing.
2379 */
2380 if (jp->pretty) {
2381 js_puts(jp, "\n");
2382 js_printf(jp, "\t");
2383 } else {
2384 if (fun->flags & JSFUN_LAMBDA)
2385 js_puts(jp, "(");
2386 }
2387 if (fun->flags & JSFUN_GETTER)
2388 js_printf(jp, "%s ", js_getter_str);
2389 else if (fun->flags & JSFUN_SETTER)
2390 js_printf(jp, "%s ", js_setter_str);
2392 js_printf(jp, "%s ", js_function_str);
2393 if (fun->atom && !QuoteString(&jp->sprinter, ATOM_TO_STRING(fun->atom), 0))
2394 return JS_FALSE;
2395 js_puts(jp, "(");
2397 if (fun->script && fun->object) {
2398 /*
2399 * Print the parameters.
2400 *
2401 * This code is complicated by the need to handle duplicate parameter
2402 * names, as required by ECMA (bah!). A duplicate parameter is stored
2403 * as another node with the same id (the parameter name) but different
2404 * shortid (the argument index) along the property tree ancestor line
2405 * starting at SCOPE_LAST_PROP(scope). Only the last duplicate param
2406 * is mapped by the scope's hash table.
2407 */
2408 cx = jp->sprinter.context;
2409 nargs = fun->nargs;
2410 mark = JS_ARENA_MARK(&cx->tempPool);
2411 JS_ARENA_ALLOCATE_CAST(params, JSAtom **, &cx->tempPool,
2412 nargs * sizeof(JSAtom *));
2413 if (!params) {
2414 JS_ReportOutOfMemory(cx);
2415 return JS_FALSE;
2416 }
2417 scope = OBJ_SCOPE(fun->object);
2418 for (sprop = SCOPE_LAST_PROP(scope); sprop; sprop = sprop->parent) {
2419 if (sprop->getter != js_GetArgument)
2420 continue;
2421 JS_ASSERT(sprop->flags & SPROP_HAS_SHORTID);
2422 JS_ASSERT((uintN) sprop->shortid < nargs);
2423 JS_ASSERT(!JSVAL_IS_INT(sprop->id));
2424 params[(uintN) sprop->shortid] = (JSAtom *) sprop->id;
2425 }
2426 for (i = 0; i < nargs; i++) {
2427 if (i > 0)
2428 js_puts(jp, ", ");
2429 if (!QuoteString(&jp->sprinter, ATOM_TO_STRING(params[i]), 0))
2430 return JS_FALSE;
2431 }
2432 JS_ARENA_RELEASE(&cx->tempPool, mark);
2433 #ifdef __GNUC__
2434 } else {
2435 scope = NULL;
2436 #endif
2437 }
2439 js_printf(jp, ") {\n");
2440 indent = jp->indent;
2441 jp->indent += 4;
2442 if (fun->script && fun->object) {
2443 oldscope = jp->scope;
2444 jp->scope = scope;
2445 ok = js_DecompileScript(jp, fun->script);
2446 jp->scope = oldscope;
2447 if (!ok) {
2448 jp->indent = indent;
2449 return JS_FALSE;
2450 }
2451 } else {
2452 js_printf(jp, native_code_str);
2453 }
2454 jp->indent -= 4;
2455 js_printf(jp, "\t}");
2457 if (jp->pretty) {
2458 js_puts(jp, "\n");
2459 } else {
2460 if (fun->flags & JSFUN_LAMBDA)
2461 js_puts(jp, ")");
2462 }
2463 return JS_TRUE;
2464 }
2466 JSString *
2467 js_DecompileValueGenerator(JSContext *cx, intN spindex, jsval v,
2468 JSString *fallback)
2469 {
2470 JSStackFrame *fp, *down;
2471 jsbytecode *pc, *begin, *end, *tmp;
2472 jsval *sp, *base, *limit;
2473 JSScript *script;
2474 JSOp op;
2475 const JSCodeSpec *cs;
2476 uint32 format, mode;
2477 intN depth;
2478 jssrcnote *sn;
2479 uintN len, off;
2480 JSPrinter *jp;
2481 JSString *name;
2483 fp = cx->fp;
2484 if (!fp)
2485 goto do_fallback;
2487 /* Try to find sp's generating pc depth slots under it on the stack. */
2488 pc = fp->pc;
2489 if (spindex == JSDVG_SEARCH_STACK) {
2490 if (!pc) {
2491 /*
2492 * Current frame is native: look under it for a scripted call
2493 * in which a decompilable bytecode string that generated the
2494 * value as an actual argument might exist.
2495 */
2496 JS_ASSERT(!fp->script && fp->fun && fp->fun->native);
2497 down = fp->down;
2498 if (!down)
2499 goto do_fallback;
2500 script = down->script;
2501 base = fp->argv;
2502 limit = base + fp->argc;
2503 } else {
2504 /*
2505 * This should be a script activation, either a top-level
2506 * script or a scripted function. But be paranoid about calls
2507 * to js_DecompileValueGenerator from code that hasn't fully
2508 * initialized a (default-all-zeroes) frame.
2509 */
2510 script = fp->script;
2511 base = fp->spbase;
2512 limit = fp->sp;
2513 }
2515 /*
2516 * Pure paranoia about default-zeroed frames being active while
2517 * js_DecompileValueGenerator is called. It can't hurt much now;
2518 * error reporting performance is not an issue.
2519 */
2520 if (!script || !base || !limit)
2521 goto do_fallback;
2523 /*
2524 * Try to find operand-generating pc depth slots below sp.
2525 *
2526 * In the native case, we know the arguments have generating pc's
2527 * under them, on account of fp->down->script being non-null: all
2528 * compiled scripts get depth slots for generating pc's allocated
2529 * upon activation, at the top of js_Interpret.
2530 *
2531 * In the script or scripted function case, the same reasoning
2532 * applies to fp rather than to fp->down.
2533 */
2534 for (sp = base; sp < limit; sp++) {
2535 if (*sp == v) {
2536 depth = (intN)script->depth;
2537 pc = (jsbytecode *) sp[-depth];
2538 break;
2539 }
2540 }
2541 } else {
2542 /*
2543 * At this point, pc may or may not be null, i.e., we could be in
2544 * a script activation, or we could be in a native frame that was
2545 * called by another native function. Check pc and script.
2546 */
2547 if (!pc)
2548 goto do_fallback;
2549 script = fp->script;
2550 if (!script)
2551 goto do_fallback;
2553 if (spindex != JSDVG_IGNORE_STACK) {
2554 JS_ASSERT(spindex < 0);
2555 depth = (intN)script->depth;
2556 #if !JS_HAS_NO_SUCH_METHOD
2557 JS_ASSERT(-depth <= spindex);
2558 #endif
2559 spindex -= depth;
2561 base = (jsval *) cx->stackPool.current->base;
2562 limit = (jsval *) cx->stackPool.current->avail;
2563 sp = fp->sp + spindex;
2564 if (JS_UPTRDIFF(sp, base) < JS_UPTRDIFF(limit, base))
2565 pc = (jsbytecode *) *sp;
2566 }
2567 }
2569 /*
2570 * Again, be paranoid, this time about possibly loading an invalid pc
2571 * from sp[-(1+depth)].
2572 */
2573 if (JS_UPTRDIFF(pc, script->code) >= (jsuword)script->length) {
2574 pc = fp->pc;
2575 if (!pc)
2576 goto do_fallback;
2577 }
2578 op = (JSOp) *pc;
2579 if (op == JSOP_TRAP)
2580 op = JS_GetTrapOpcode(cx, script, pc);
2582 /* XXX handle null as a special case, to avoid calling null "object" */
2583 if (op == JSOP_NULL)
2584 return ATOM_TO_STRING(cx->runtime->atomState.nullAtom);
2586 cs = &js_CodeSpec[op];
2587 format = cs->format;
2588 mode = (format & JOF_MODEMASK);
2590 /* NAME ops are self-contained, but others require left context. */
2591 if (mode == JOF_NAME) {
2592 begin = pc;
2593 } else {
2594 sn = js_GetSrcNote(script, pc);
2595 if (!sn || SN_TYPE(sn) != SRC_PCBASE)
2596 goto do_fallback;
2597 begin = pc - js_GetSrcNoteOffset(sn, 0);
2598 }
2599 end = pc + cs->length;
2600 len = PTRDIFF(end, begin, jsbytecode);
2602 if (format & (JOF_SET | JOF_DEL | JOF_INCDEC | JOF_IMPORT | JOF_FOR)) {
2603 tmp = (jsbytecode *) JS_malloc(cx, len * sizeof(jsbytecode));
2604 if (!tmp)
2605 return NULL;
2606 memcpy(tmp, begin, len * sizeof(jsbytecode));
2607 if (mode == JOF_NAME) {
2608 tmp[0] = JSOP_NAME;
2609 } else {
2610 /*
2611 * We must replace the faulting pc's bytecode with a corresponding
2612 * JSOP_GET* code. For JSOP_SET{PROP,ELEM}, we must use the "2nd"
2613 * form of JSOP_GET{PROP,ELEM}, to throw away the assignment op's
2614 * right-hand operand and decompile it as if it were a GET of its
2615 * left-hand operand.
2616 */
2617 off = len - cs->length;
2618 JS_ASSERT(off == (uintN) PTRDIFF(pc, begin, jsbytecode));
2619 if (mode == JOF_PROP) {
2620 tmp[off] = (format & JOF_SET) ? JSOP_GETPROP2 : JSOP_GETPROP;
2621 } else if (mode == JOF_ELEM) {
2622 tmp[off] = (format & JOF_SET) ? JSOP_GETELEM2 : JSOP_GETELEM;
2623 } else {
2624 /*
2625 * A zero mode means precisely that op is uncategorized for our
2626 * purposes, so we must write per-op special case code here.
2627 */
2628 switch (op) {
2629 case JSOP_ENUMELEM:
2630 tmp[off] = JSOP_GETELEM;
2631 break;
2632 #if JS_HAS_LVALUE_RETURN
2633 case JSOP_SETCALL:
2634 tmp[off] = JSOP_CALL;
2635 break;
2636 #endif
2637 default:
2638 JS_ASSERT(0);
2639 }
2640 }
2641 }
2642 begin = tmp;
2643 } else {
2644 /* No need to revise script bytecode. */
2645 tmp = NULL;
2646 }
2648 jp = js_NewPrinter(cx, "js_DecompileValueGenerator", 0, JS_FALSE);
2649 if (jp && js_DecompileCode(jp, script, begin, len))
2650 name = js_GetPrinterOutput(jp);
2651 else
2652 name = NULL;
2653 js_DestroyPrinter(jp);
2654 if (tmp)
2655 JS_free(cx, tmp);
2656 return name;
2658 do_fallback:
2659 return fallback ? fallback : js_ValueToString(cx, v);
2660 }