DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Implementation

Mercurial (5216dd412535)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Mozilla Communicator client code, released
 * March 31, 1998.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

#ifndef jsopcode_h___
#define jsopcode_h___
/*
 * JS bytecode definitions.
 */
#include <stddef.h>
#include "jsprvtd.h"
#include "jspubtd.h"
#include "jsutil.h"

#ifdef __cplusplus
# include "jsvalue.h"
#endif

JS_BEGIN_EXTERN_C

/*
 * JS operation bytecodes.
 */
typedef enum JSOp {
#define OPDEF(op,val,name,token,length,nuses,ndefs,prec,format) \
    op = val,
#include "jsopcode.tbl"
#undef OPDEF
    JSOP_LIMIT,

    /*
     * These pseudo-ops help js_DecompileValueGenerator decompile JSOP_SETNAME,
     * JSOP_SETPROP, and JSOP_SETELEM, respectively.  They are never stored in
     * bytecode, so they don't preempt valid opcodes.
     */
    JSOP_GETPROP2 = JSOP_LIMIT,
    JSOP_GETELEM2 = JSOP_LIMIT + 1,
    JSOP_FAKE_LIMIT = JSOP_GETELEM2
} JSOp;

/*
 * JS bytecode formats.
 */
#define JOF_BYTE          0       /* single bytecode, no immediates */
#define JOF_JUMP          1       /* signed 16-bit jump offset immediate */
#define JOF_ATOM          2       /* unsigned 16-bit constant index */
#define JOF_UINT16        3       /* unsigned 16-bit immediate operand */
#define JOF_TABLESWITCH   4       /* table switch */
#define JOF_LOOKUPSWITCH  5       /* lookup switch */
#define JOF_QARG          6       /* quickened get/set function argument ops */
#define JOF_LOCAL         7       /* var or block-local variable */
#define JOF_SLOTATOM      8       /* uint16 slot + constant index */
#define JOF_JUMPX         9       /* signed 32-bit jump offset immediate */
#define JOF_TABLESWITCHX  10      /* extended (32-bit offset) table switch */
#define JOF_LOOKUPSWITCHX 11      /* extended (32-bit offset) lookup switch */
#define JOF_UINT24        12      /* extended unsigned 24-bit literal (index) */
#define JOF_UINT8         13      /* uint8 immediate, e.g. top 8 bits of 24-bit
                                     atom index */
#define JOF_INT32         14      /* int32 immediate operand */
#define JOF_OBJECT        15      /* unsigned 16-bit object index */
#define JOF_SLOTOBJECT    16      /* uint16 slot index + object index */
#define JOF_REGEXP        17      /* unsigned 16-bit regexp index */
#define JOF_INT8          18      /* int8 immediate operand */
#define JOF_ATOMOBJECT    19      /* uint16 constant index + object index */
#define JOF_UINT16PAIR    20      /* pair of uint16 immediates */
#define JOF_GLOBAL        21      /* uint16 global array index */
#define JOF_TYPEMASK      0x001f  /* mask for above immediate types */

#define JOF_NAME          (1U<<5) /* name operation */
#define JOF_PROP          (2U<<5) /* obj.prop operation */
#define JOF_ELEM          (3U<<5) /* obj[index] operation */
#define JOF_XMLNAME       (4U<<5) /* XML name: *, a::b, @a, @a::b, etc. */
#define JOF_VARPROP       (5U<<5) /* x.prop for this, arg, var, or local x */
#define JOF_MODEMASK      (7U<<5) /* mask for above addressing modes */
#define JOF_SET           (1U<<8) /* set (i.e., assignment) operation */
#define JOF_DEL           (1U<<9) /* delete operation */
#define JOF_DEC          (1U<<10) /* decrement (--, not ++) opcode */
#define JOF_INC          (2U<<10) /* increment (++, not --) opcode */
#define JOF_INCDEC       (3U<<10) /* increment or decrement opcode */
#define JOF_POST         (1U<<12) /* postorder increment or decrement */
#define JOF_FOR          (1U<<13) /* for-in property op (akin to JOF_SET) */
#define JOF_ASSIGNING     JOF_SET /* hint for Class.resolve, used for ops
                                     that do simplex assignment */
#define JOF_DETECTING    (1U<<14) /* object detection for JSNewResolveOp */
#define JOF_BACKPATCH    (1U<<15) /* backpatch placeholder during codegen */
#define JOF_LEFTASSOC    (1U<<16) /* left-associative operator */
#define JOF_DECLARING    (1U<<17) /* var, const, or function declaration op */
#define JOF_INDEXBASE    (1U<<18) /* atom segment base setting prefix op */
#define JOF_CALLOP       (1U<<19) /* call operation that pushes function and
                                     this */
#define JOF_PARENHEAD    (1U<<20) /* opcode consumes value of expression in
                                     parenthesized statement head */
#define JOF_INVOKE       (1U<<21) /* JSOP_CALL, JSOP_NEW, JSOP_EVAL */
#define JOF_TMPSLOT      (1U<<22) /* interpreter uses extra temporary slot
                                     to root intermediate objects besides
                                     the slots opcode uses */
#define JOF_TMPSLOT2     (2U<<22) /* interpreter uses extra 2 temporary slot
                                     besides the slots opcode uses */
#define JOF_TMPSLOT3     (3U<<22) /* interpreter uses extra 3 temporary slot
                                     besides the slots opcode uses */
#define JOF_TMPSLOT_SHIFT 22
#define JOF_TMPSLOT_MASK  (JS_BITMASK(2) << JOF_TMPSLOT_SHIFT)

#define JOF_SHARPSLOT    (1U<<24) /* first immediate is uint16 stack slot no.
                                     that needs fixup when in global code (see
                                     Compiler::compileScript) */
#define JOF_GNAME        (1U<<25) /* predicted global name */

/* Shorthands for type from format and type from opcode. */
#define JOF_TYPE(fmt)   ((fmt) & JOF_TYPEMASK)
#define JOF_OPTYPE(op)  JOF_TYPE(js_CodeSpec[op].format)

/* Shorthands for mode from format and mode from opcode. */
#define JOF_MODE(fmt)   ((fmt) & JOF_MODEMASK)
#define JOF_OPMODE(op)  JOF_MODE(js_CodeSpec[op].format)

#define JOF_TYPE_IS_EXTENDED_JUMP(t) \
    ((unsigned)((t) - JOF_JUMPX) <= (unsigned)(JOF_LOOKUPSWITCHX - JOF_JUMPX))

/*
 * Immediate operand getters, setters, and bounds.
 */

/* Common uint16 immediate format helpers. */
#define UINT16_LEN              2
#define UINT16_HI(i)            ((jsbytecode)((i) >> 8))
#define UINT16_LO(i)            ((jsbytecode)(i))
#define GET_UINT16(pc)          ((uintN)(((pc)[1] << 8) | (pc)[2]))
#define SET_UINT16(pc,i)        ((pc)[1] = UINT16_HI(i), (pc)[2] = UINT16_LO(i))
#define UINT16_LIMIT            ((uintN)1 << 16)

/* Short (2-byte signed offset) relative jump macros. */
#define JUMP_OFFSET_LEN         2
#define JUMP_OFFSET_HI(off)     ((jsbytecode)((off) >> 8))
#define JUMP_OFFSET_LO(off)     ((jsbytecode)(off))
#define GET_JUMP_OFFSET(pc)     ((int16)GET_UINT16(pc))
#define SET_JUMP_OFFSET(pc,off) ((pc)[1] = JUMP_OFFSET_HI(off),               \
                                 (pc)[2] = JUMP_OFFSET_LO(off))
#define JUMP_OFFSET_MIN         ((int16)0x8000)
#define JUMP_OFFSET_MAX         ((int16)0x7fff)

/*
 * When a short jump won't hold a relative offset, its 2-byte immediate offset
 * operand is an unsigned index of a span-dependency record, maintained until
 * code generation finishes -- after which some (but we hope not nearly all)
 * span-dependent jumps must be extended (see OptimizeSpanDeps in jsemit.c).
 *
 * If the span-dependency record index overflows SPANDEP_INDEX_MAX, the jump
 * offset will contain SPANDEP_INDEX_HUGE, indicating that the record must be
 * found (via binary search) by its "before span-dependency optimization" pc
 * offset (from script main entry point).
 */
#define GET_SPANDEP_INDEX(pc)   ((uint16)GET_UINT16(pc))
#define SET_SPANDEP_INDEX(pc,i) ((pc)[1] = JUMP_OFFSET_HI(i),                 \
                                 (pc)[2] = JUMP_OFFSET_LO(i))
#define SPANDEP_INDEX_MAX       ((uint16)0xfffe)
#define SPANDEP_INDEX_HUGE      ((uint16)0xffff)

/* Ultimately, if short jumps won't do, emit long (4-byte signed) offsets. */
#define JUMPX_OFFSET_LEN        4
#define JUMPX_OFFSET_B3(off)    ((jsbytecode)((off) >> 24))
#define JUMPX_OFFSET_B2(off)    ((jsbytecode)((off) >> 16))
#define JUMPX_OFFSET_B1(off)    ((jsbytecode)((off) >> 8))
#define JUMPX_OFFSET_B0(off)    ((jsbytecode)(off))
#define GET_JUMPX_OFFSET(pc)    ((int32)(((pc)[1] << 24) | ((pc)[2] << 16)    \
                                         | ((pc)[3] << 8) | (pc)[4]))
#define SET_JUMPX_OFFSET(pc,off)((pc)[1] = JUMPX_OFFSET_B3(off),              \
                                 (pc)[2] = JUMPX_OFFSET_B2(off),              \
                                 (pc)[3] = JUMPX_OFFSET_B1(off),              \
                                 (pc)[4] = JUMPX_OFFSET_B0(off))
#define JUMPX_OFFSET_MIN        ((int32)0x80000000)
#define JUMPX_OFFSET_MAX        ((int32)0x7fffffff)

/*
 * A literal is indexed by a per-script atom or object maps. Most scripts
 * have relatively few literals, so the standard JOF_ATOM, JOF_OBJECT and
 * JOF_REGEXP formats specifies a fixed 16 bits of immediate operand index.
 * A script with more than 64K literals must wrap the bytecode into
 * JSOP_INDEXBASE and JSOP_RESETBASE pair.
 */
#define INDEX_LEN               2
#define INDEX_HI(i)             ((jsbytecode)((i) >> 8))
#define INDEX_LO(i)             ((jsbytecode)(i))
#define GET_INDEX(pc)           GET_UINT16(pc)
#define SET_INDEX(pc,i)         ((pc)[1] = INDEX_HI(i), (pc)[2] = INDEX_LO(i))

#define GET_INDEXBASE(pc)       (JS_ASSERT(*(pc) == JSOP_INDEXBASE),          \
                                 ((uintN)((pc)[1])) << 16)
#define INDEXBASE_LEN           1

#define UINT24_HI(i)            ((jsbytecode)((i) >> 16))
#define UINT24_MID(i)           ((jsbytecode)((i) >> 8))
#define UINT24_LO(i)            ((jsbytecode)(i))
#define GET_UINT24(pc)          ((jsatomid)(((pc)[1] << 16) |                 \
                                            ((pc)[2] << 8) |                  \
                                            (pc)[3]))
#define SET_UINT24(pc,i)        ((pc)[1] = UINT24_HI(i),                      \
                                 (pc)[2] = UINT24_MID(i),                     \
                                 (pc)[3] = UINT24_LO(i))

#define GET_INT8(pc)            ((jsint)(int8)(pc)[1])

#define GET_INT32(pc)           ((jsint)(((uint32)((pc)[1]) << 24) |          \
                                         ((uint32)((pc)[2]) << 16) |          \
                                         ((uint32)((pc)[3]) << 8)  |          \
                                         (uint32)(pc)[4]))
#define SET_INT32(pc,i)         ((pc)[1] = (jsbytecode)((uint32)(i) >> 24),   \
                                 (pc)[2] = (jsbytecode)((uint32)(i) >> 16),   \
                                 (pc)[3] = (jsbytecode)((uint32)(i) >> 8),    \
                                 (pc)[4] = (jsbytecode)(uint32)(i))

/* Index limit is determined by SN_3BYTE_OFFSET_FLAG, see jsemit.h. */
#define INDEX_LIMIT_LOG2        23
#define INDEX_LIMIT             ((uint32)1 << INDEX_LIMIT_LOG2)

/* Actual argument count operand format helpers. */
#define ARGC_HI(argc)           UINT16_HI(argc)
#define ARGC_LO(argc)           UINT16_LO(argc)
#define GET_ARGC(pc)            GET_UINT16(pc)
#define ARGC_LIMIT              UINT16_LIMIT

/* Synonyms for quick JOF_QARG and JOF_LOCAL bytecodes. */
#define GET_ARGNO(pc)           GET_UINT16(pc)
#define SET_ARGNO(pc,argno)     SET_UINT16(pc,argno)
#define ARGNO_LEN               2
#define ARGNO_LIMIT             UINT16_LIMIT

#define GET_SLOTNO(pc)          GET_UINT16(pc)
#define SET_SLOTNO(pc,varno)    SET_UINT16(pc,varno)
#define SLOTNO_LEN              2
#define SLOTNO_LIMIT            UINT16_LIMIT

struct JSCodeSpec {
    int8                length;         /* length including opcode byte */
    int8                nuses;          /* arity, -1 if variadic */
    int8                ndefs;          /* number of stack results */
    uint8               prec;           /* operator precedence */
    uint32              format;         /* immediate operand format */

#ifdef __cplusplus
    uint32 type() const { return JOF_TYPE(format); }
#endif
};

extern const JSCodeSpec js_CodeSpec[];
extern uintN            js_NumCodeSpecs;
extern const char       *js_CodeName[];
extern const char       js_EscapeMap[];

/* Silence unreferenced formal parameter warnings */
#ifdef _MSC_VER
#pragma warning(push)
#pragma warning(disable:4100)
#endif

/*
 * Return a GC'ed string containing the chars in str, with any non-printing
 * chars or quotes (' or " as specified by the quote argument) escaped, and
 * with the quote character at the beginning and end of the result string.
 */
extern JSString *
js_QuoteString(JSContext *cx, JSString *str, jschar quote);

/*
 * JSPrinter operations, for printf style message formatting.  The return
 * value from js_GetPrinterOutput() is the printer's cumulative output, in
 * a GC'ed string.
 *
 * strict is true if the context in which the output will appear has
 * already been marked as strict, thus indicating that nested
 * functions need not be re-marked with a strict directive.  It should
 * be false in the outermost printer.
 */

extern JSPrinter *
js_NewPrinter(JSContext *cx, const char *name, JSFunction *fun,
              uintN indent, JSBool pretty, JSBool grouped, JSBool strict);

extern void
js_DestroyPrinter(JSPrinter *jp);

extern JSString *
js_GetPrinterOutput(JSPrinter *jp);

extern int
js_printf(JSPrinter *jp, const char *format, ...);

extern JSBool
js_puts(JSPrinter *jp, const char *s);

/*
 * Get index operand from the bytecode using a bytecode analysis to deduce the
 * the index register. This function is infallible, in spite of taking cx as
 * its first parameter; it uses only cx->runtime when calling JS_GetTrapOpcode.
 * The GET_*_FROM_BYTECODE macros that call it pick up cx from their caller's
 * lexical environments.
 */
uintN
js_GetIndexFromBytecode(JSContext *cx, JSScript *script, jsbytecode *pc,
                        ptrdiff_t pcoff);

/*
 * A slower version of GET_ATOM when the caller does not want to maintain
 * the index segment register itself.
 */
#define GET_ATOM_FROM_BYTECODE(script, pc, pcoff, atom)                       \
    JS_BEGIN_MACRO                                                            \
        JS_ASSERT(*(pc) != JSOP_DOUBLE);                                      \
        uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff));  \
        JS_GET_SCRIPT_ATOM(script, pc, index_, atom);                         \
    JS_END_MACRO

/*
 * Variant for getting a double atom when we might be in an imacro. Bytecodes
 * with literals that are only ever doubles must use this macro, and never use
 * GET_ATOM_FROM_BYTECODE or JS_GET_SCRIPT_ATOM.
 *
 * Unfortunately some bytecodes such as JSOP_LOOKUPSWITCH have immediates that
 * might be string or double atoms. Those opcodes cannot be used from imacros.
 * See the assertions in the JSOP_DOUBLE and JSOP_LOOKUPSWTICH* opcode cases in
 * jsinterp.cpp.
 */
#define GET_DOUBLE_FROM_BYTECODE(script, pc, pcoff, dbl)                      \
    JS_BEGIN_MACRO                                                            \
        uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff));  \
        JS_ASSERT(index_ < (script)->consts()->length);                       \
        (dbl) = (script)->getConst(index_).toDouble();                        \
    JS_END_MACRO

#define GET_OBJECT_FROM_BYTECODE(script, pc, pcoff, obj)                      \
    JS_BEGIN_MACRO                                                            \
        uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff));  \
        obj = (script)->getObject(index_);                                    \
    JS_END_MACRO

#define GET_FUNCTION_FROM_BYTECODE(script, pc, pcoff, fun)                    \
    JS_BEGIN_MACRO                                                            \
        uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff));  \
        fun = (script)->getFunction(index_);                                  \
    JS_END_MACRO

#define GET_REGEXP_FROM_BYTECODE(script, pc, pcoff, obj)                      \
    JS_BEGIN_MACRO                                                            \
        uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff));  \
        obj = (script)->getRegExp(index_);                                    \
    JS_END_MACRO

/*
 * Get the length of variable-length bytecode like JSOP_TABLESWITCH.
 */
extern uintN
js_GetVariableBytecodeLength(jsbytecode *pc);

/*
 * Find the number of stack slots used by a variadic opcode such as JSOP_CALL
 * (for such ops, JSCodeSpec.nuses is -1).
 */
extern uintN
js_GetVariableStackUses(JSOp op, jsbytecode *pc);

/*
 * Find the number of stack slots defined by JSOP_ENTERBLOCK (for this op,
 * JSCodeSpec.ndefs is -1).
 */
extern uintN
js_GetEnterBlockStackDefs(JSContext *cx, JSScript *script, jsbytecode *pc);

#ifdef __cplusplus /* Aargh, libgjs, bug 492720. */
static JS_INLINE uintN
js_GetStackUses(const JSCodeSpec *cs, JSOp op, jsbytecode *pc)
{
    JS_ASSERT(cs == &js_CodeSpec[op]);
    if (cs->nuses >= 0)
        return cs->nuses;
    return js_GetVariableStackUses(op, pc);
}

static JS_INLINE uintN
js_GetStackDefs(JSContext *cx, const JSCodeSpec *cs, JSOp op, JSScript *script,
                jsbytecode *pc)
{
    JS_ASSERT(cs == &js_CodeSpec[op]);
    if (cs->ndefs >= 0)
        return cs->ndefs;

    /* Only JSOP_ENTERBLOCK has a variable number of stack defs. */
    JS_ASSERT(op == JSOP_ENTERBLOCK);
    return js_GetEnterBlockStackDefs(cx, script, pc);
}
#endif

#ifdef DEBUG
/*
 * Disassemblers, for debugging only.
 */
#include <stdio.h>

extern JS_FRIEND_API(JSBool)
js_Disassemble(JSContext *cx, JSScript *script, JSBool lines, FILE *fp);

extern JS_FRIEND_API(uintN)
js_Disassemble1(JSContext *cx, JSScript *script, jsbytecode *pc, uintN loc,
                JSBool lines, FILE *fp);
#endif /* DEBUG */

/*
 * Decompilers, for script, function, and expression pretty-printing.
 */
extern JSBool
js_DecompileScript(JSPrinter *jp, JSScript *script);

extern JSBool
js_DecompileFunctionBody(JSPrinter *jp);

extern JSBool
js_DecompileFunction(JSPrinter *jp);

/*
 * Some C++ compilers treat the language linkage (extern "C" vs.
 * extern "C++") as part of function (and thus pointer-to-function)
 * types. The use of this typedef (defined in "C") ensures that
 * js_DecompileToString's definition (in "C++") gets matched up with
 * this declaration.
 */
typedef JSBool (* JSDecompilerPtr)(JSPrinter *);

extern JSString *
js_DecompileToString(JSContext *cx, const char *name, JSFunction *fun,
                     uintN indent, JSBool pretty, JSBool grouped, JSBool strict,
                     JSDecompilerPtr decompiler);

/*
 * Find the source expression that resulted in v, and return a newly allocated
 * C-string containing it.  Fall back on v's string conversion (fallback) if we
 * can't find the bytecode that generated and pushed v on the operand stack.
 *
 * Search the current stack frame if spindex is JSDVG_SEARCH_STACK.  Don't
 * look for v on the stack if spindex is JSDVG_IGNORE_STACK.  Otherwise,
 * spindex is the negative index of v, measured from cx->fp->sp, or from a
 * lower frame's sp if cx->fp is native.
 *
 * The caller must call JS_free on the result after a succsesful call.
 */
extern char *
js_DecompileValueGenerator(JSContext *cx, intN spindex, jsval v,
                           JSString *fallback);

#define JSDVG_IGNORE_STACK      0
#define JSDVG_SEARCH_STACK      1

#ifdef __cplusplus
namespace js {

static inline char *
DecompileValueGenerator(JSContext *cx, intN spindex, const Value &v,
                        JSString *fallback)
{
    return js_DecompileValueGenerator(cx, spindex, Jsvalify(v), fallback);
}

}
#endif

/*
 * Given bytecode address pc in script's main program code, return the operand
 * stack depth just before (JSOp) *pc executes.
 */
extern uintN
js_ReconstructStackDepth(JSContext *cx, JSScript *script, jsbytecode *pc);

#ifdef _MSC_VER
#pragma warning(pop)
#endif

JS_END_EXTERN_C

#endif /* jsopcode_h___ */