/js/lib/Socket.IO-node/support/expresso/deps/jscoverage/js/jsopcode.h
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Possible License(s): GPL-2.0, LGPL-2.1, MPL-2.0-no-copyleft-exception, BSD-3-Clause
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 ***** */
39
40#ifndef jsopcode_h___
41#define jsopcode_h___
42/*
43 * JS bytecode definitions.
44 */
45#include <stddef.h>
46#include "jsprvtd.h"
47#include "jspubtd.h"
48#include "jsutil.h"
49
50JS_BEGIN_EXTERN_C
51
52/*
53 * JS operation bytecodes.
54 */
55typedef enum JSOp {
56#define OPDEF(op,val,name,token,length,nuses,ndefs,prec,format) \
57 op = val,
58#include "jsopcode.tbl"
59#undef OPDEF
60 JSOP_LIMIT
61} JSOp;
62
63/*
64 * JS bytecode formats.
65 */
66#define JOF_BYTE 0 /* single bytecode, no immediates */
67#define JOF_JUMP 1 /* signed 16-bit jump offset immediate */
68#define JOF_ATOM 2 /* unsigned 16-bit constant pool index */
69#define JOF_UINT16 3 /* unsigned 16-bit immediate operand */
70#define JOF_TABLESWITCH 4 /* table switch */
71#define JOF_LOOKUPSWITCH 5 /* lookup switch */
72#define JOF_QARG 6 /* quickened get/set function argument ops */
73#define JOF_LOCAL 7 /* var or block-local variable */
74#define JOF_SLOTATOM 8 /* uint16 slot index + constant pool index */
75#define JOF_JUMPX 9 /* signed 32-bit jump offset immediate */
76#define JOF_TABLESWITCHX 10 /* extended (32-bit offset) table switch */
77#define JOF_LOOKUPSWITCHX 11 /* extended (32-bit offset) lookup switch */
78#define JOF_UINT24 12 /* extended unsigned 24-bit literal (index) */
79#define JOF_UINT8 13 /* uint8 immediate, e.g. top 8 bits of 24-bit
80 atom index */
81#define JOF_INT32 14 /* int32 immediate operand */
82#define JOF_OBJECT 15 /* unsigned 16-bit object pool index */
83#define JOF_SLOTOBJECT 16 /* uint16 slot index + object pool index */
84#define JOF_REGEXP 17 /* unsigned 16-bit regexp pool index */
85#define JOF_INT8 18 /* int8 immediate operand */
86#define JOF_TYPEMASK 0x001f /* mask for above immediate types */
87
88#define JOF_NAME (1U<<5) /* name operation */
89#define JOF_PROP (2U<<5) /* obj.prop operation */
90#define JOF_ELEM (3U<<5) /* obj[index] operation */
91#define JOF_XMLNAME (4U<<5) /* XML name: *, a::b, @a, @a::b, etc. */
92#define JOF_VARPROP (5U<<5) /* x.prop for this, arg, var, or local x */
93#define JOF_MODEMASK (7U<<5) /* mask for above addressing modes */
94#define JOF_SET (1U<<8) /* set (i.e., assignment) operation */
95#define JOF_DEL (1U<<9) /* delete operation */
96#define JOF_DEC (1U<<10) /* decrement (--, not ++) opcode */
97#define JOF_INC (2U<<10) /* increment (++, not --) opcode */
98#define JOF_INCDEC (3U<<10) /* increment or decrement opcode */
99#define JOF_POST (1U<<12) /* postorder increment or decrement */
100#define JOF_FOR (1U<<13) /* for-in property op (akin to JOF_SET) */
101#define JOF_ASSIGNING JOF_SET /* hint for JSClass.resolve, used for ops
102 that do simplex assignment */
103#define JOF_DETECTING (1U<<14) /* object detection for JSNewResolveOp */
104#define JOF_BACKPATCH (1U<<15) /* backpatch placeholder during codegen */
105#define JOF_LEFTASSOC (1U<<16) /* left-associative operator */
106#define JOF_DECLARING (1U<<17) /* var, const, or function declaration op */
107#define JOF_INDEXBASE (1U<<18) /* atom segment base setting prefix op */
108#define JOF_CALLOP (1U<<19) /* call operation that pushes function and
109 this */
110#define JOF_PARENHEAD (1U<<20) /* opcode consumes value of expression in
111 parenthesized statement head */
112#define JOF_INVOKE (1U<<21) /* JSOP_CALL, JSOP_NEW, JSOP_EVAL */
113#define JOF_TMPSLOT (1U<<22) /* interpreter uses extra temporary slot
114 to root intermediate objects besides
115 the slots opcode uses */
116#define JOF_TMPSLOT2 (2U<<22) /* interpreter uses extra 2 temporary slot
117 besides the slots opcode uses */
118#define JOF_TMPSLOT_SHIFT 22
119#define JOF_TMPSLOT_MASK (JS_BITMASK(2) << JOF_TMPSLOT_SHIFT)
120
121/* Shorthands for type from format and type from opcode. */
122#define JOF_TYPE(fmt) ((fmt) & JOF_TYPEMASK)
123#define JOF_OPTYPE(op) JOF_TYPE(js_CodeSpec[op].format)
124
125/* Shorthands for mode from format and mode from opcode. */
126#define JOF_MODE(fmt) ((fmt) & JOF_MODEMASK)
127#define JOF_OPMODE(op) JOF_MODE(js_CodeSpec[op].format)
128
129#define JOF_TYPE_IS_EXTENDED_JUMP(t) \
130 ((unsigned)((t) - JOF_JUMPX) <= (unsigned)(JOF_LOOKUPSWITCHX - JOF_JUMPX))
131
132/*
133 * Immediate operand getters, setters, and bounds.
134 */
135
136/* Common uint16 immediate format helpers. */
137#define UINT16_LEN 2
138#define UINT16_HI(i) ((jsbytecode)((i) >> 8))
139#define UINT16_LO(i) ((jsbytecode)(i))
140#define GET_UINT16(pc) ((uintN)(((pc)[1] << 8) | (pc)[2]))
141#define SET_UINT16(pc,i) ((pc)[1] = UINT16_HI(i), (pc)[2] = UINT16_LO(i))
142#define UINT16_LIMIT ((uintN)1 << 16)
143
144/* Short (2-byte signed offset) relative jump macros. */
145#define JUMP_OFFSET_LEN 2
146#define JUMP_OFFSET_HI(off) ((jsbytecode)((off) >> 8))
147#define JUMP_OFFSET_LO(off) ((jsbytecode)(off))
148#define GET_JUMP_OFFSET(pc) ((int16)GET_UINT16(pc))
149#define SET_JUMP_OFFSET(pc,off) ((pc)[1] = JUMP_OFFSET_HI(off), \
150 (pc)[2] = JUMP_OFFSET_LO(off))
151#define JUMP_OFFSET_MIN ((int16)0x8000)
152#define JUMP_OFFSET_MAX ((int16)0x7fff)
153
154/*
155 * When a short jump won't hold a relative offset, its 2-byte immediate offset
156 * operand is an unsigned index of a span-dependency record, maintained until
157 * code generation finishes -- after which some (but we hope not nearly all)
158 * span-dependent jumps must be extended (see OptimizeSpanDeps in jsemit.c).
159 *
160 * If the span-dependency record index overflows SPANDEP_INDEX_MAX, the jump
161 * offset will contain SPANDEP_INDEX_HUGE, indicating that the record must be
162 * found (via binary search) by its "before span-dependency optimization" pc
163 * offset (from script main entry point).
164 */
165#define GET_SPANDEP_INDEX(pc) ((uint16)GET_UINT16(pc))
166#define SET_SPANDEP_INDEX(pc,i) ((pc)[1] = JUMP_OFFSET_HI(i), \
167 (pc)[2] = JUMP_OFFSET_LO(i))
168#define SPANDEP_INDEX_MAX ((uint16)0xfffe)
169#define SPANDEP_INDEX_HUGE ((uint16)0xffff)
170
171/* Ultimately, if short jumps won't do, emit long (4-byte signed) offsets. */
172#define JUMPX_OFFSET_LEN 4
173#define JUMPX_OFFSET_B3(off) ((jsbytecode)((off) >> 24))
174#define JUMPX_OFFSET_B2(off) ((jsbytecode)((off) >> 16))
175#define JUMPX_OFFSET_B1(off) ((jsbytecode)((off) >> 8))
176#define JUMPX_OFFSET_B0(off) ((jsbytecode)(off))
177#define GET_JUMPX_OFFSET(pc) ((int32)(((pc)[1] << 24) | ((pc)[2] << 16) \
178 | ((pc)[3] << 8) | (pc)[4]))
179#define SET_JUMPX_OFFSET(pc,off)((pc)[1] = JUMPX_OFFSET_B3(off), \
180 (pc)[2] = JUMPX_OFFSET_B2(off), \
181 (pc)[3] = JUMPX_OFFSET_B1(off), \
182 (pc)[4] = JUMPX_OFFSET_B0(off))
183#define JUMPX_OFFSET_MIN ((int32)0x80000000)
184#define JUMPX_OFFSET_MAX ((int32)0x7fffffff)
185
186/*
187 * A literal is indexed by a per-script atom or object maps. Most scripts
188 * have relatively few literals, so the standard JOF_ATOM, JOF_OBJECT and
189 * JOF_REGEXP formats specifies a fixed 16 bits of immediate operand index.
190 * A script with more than 64K literals must wrap the bytecode into
191 * JSOP_INDEXBASE and JSOP_RESETBASE pair.
192 */
193#define INDEX_LEN 2
194#define INDEX_HI(i) ((jsbytecode)((i) >> 8))
195#define INDEX_LO(i) ((jsbytecode)(i))
196#define GET_INDEX(pc) GET_UINT16(pc)
197#define SET_INDEX(pc,i) ((pc)[1] = INDEX_HI(i), (pc)[2] = INDEX_LO(i))
198
199#define GET_INDEXBASE(pc) (JS_ASSERT(*(pc) == JSOP_INDEXBASE), \
200 ((uintN)((pc)[1])) << 16)
201#define INDEXBASE_LEN 1
202
203#define UINT24_HI(i) ((jsbytecode)((i) >> 16))
204#define UINT24_MID(i) ((jsbytecode)((i) >> 8))
205#define UINT24_LO(i) ((jsbytecode)(i))
206#define GET_UINT24(pc) ((jsatomid)(((pc)[1] << 16) | \
207 ((pc)[2] << 8) | \
208 (pc)[3]))
209#define SET_UINT24(pc,i) ((pc)[1] = UINT24_HI(i), \
210 (pc)[2] = UINT24_MID(i), \
211 (pc)[3] = UINT24_LO(i))
212
213#define GET_INT8(pc) ((jsint)(int8)(pc)[1])
214
215#define GET_INT32(pc) ((jsint)(((uint32)((pc)[1]) << 24) | \
216 ((uint32)((pc)[2]) << 16) | \
217 ((uint32)((pc)[3]) << 8) | \
218 (uint32)(pc)[4]))
219#define SET_INT32(pc,i) ((pc)[1] = (jsbytecode)((uint32)(i) >> 24), \
220 (pc)[2] = (jsbytecode)((uint32)(i) >> 16), \
221 (pc)[3] = (jsbytecode)((uint32)(i) >> 8), \
222 (pc)[4] = (jsbytecode)(uint32)(i))
223
224/* Index limit is determined by SN_3BYTE_OFFSET_FLAG, see jsemit.h. */
225#define INDEX_LIMIT_LOG2 23
226#define INDEX_LIMIT ((uint32)1 << INDEX_LIMIT_LOG2)
227
228JS_STATIC_ASSERT(sizeof(uint32) * JS_BITS_PER_BYTE >= INDEX_LIMIT_LOG2 + 1);
229
230/* Actual argument count operand format helpers. */
231#define ARGC_HI(argc) UINT16_HI(argc)
232#define ARGC_LO(argc) UINT16_LO(argc)
233#define GET_ARGC(pc) GET_UINT16(pc)
234#define ARGC_LIMIT UINT16_LIMIT
235
236/* Synonyms for quick JOF_QARG and JOF_LOCAL bytecodes. */
237#define GET_ARGNO(pc) GET_UINT16(pc)
238#define SET_ARGNO(pc,argno) SET_UINT16(pc,argno)
239#define ARGNO_LEN 2
240#define ARGNO_LIMIT UINT16_LIMIT
241
242#define GET_SLOTNO(pc) GET_UINT16(pc)
243#define SET_SLOTNO(pc,varno) SET_UINT16(pc,varno)
244#define SLOTNO_LEN 2
245#define SLOTNO_LIMIT UINT16_LIMIT
246
247struct JSCodeSpec {
248 int8 length; /* length including opcode byte */
249 int8 nuses; /* arity, -1 if variadic */
250 int8 ndefs; /* number of stack results */
251 uint8 prec; /* operator precedence */
252 uint32 format; /* immediate operand format */
253};
254
255extern const JSCodeSpec js_CodeSpec[];
256extern uintN js_NumCodeSpecs;
257extern const char *js_CodeName[];
258extern const char js_EscapeMap[];
259
260/*
261 * Return a GC'ed string containing the chars in str, with any non-printing
262 * chars or quotes (' or " as specified by the quote argument) escaped, and
263 * with the quote character at the beginning and end of the result string.
264 */
265extern JSString *
266js_QuoteString(JSContext *cx, JSString *str, jschar quote);
267
268/*
269 * JSPrinter operations, for printf style message formatting. The return
270 * value from js_GetPrinterOutput() is the printer's cumulative output, in
271 * a GC'ed string.
272 */
273
274#ifdef JS_ARENAMETER
275# define JS_NEW_PRINTER(cx, name, fun, indent, pretty) \
276 js_NewPrinter(cx, name, fun, indent, pretty)
277#else
278# define JS_NEW_PRINTER(cx, name, fun, indent, pretty) \
279 js_NewPrinter(cx, fun, indent, pretty)
280#endif
281
282extern JSPrinter *
283JS_NEW_PRINTER(JSContext *cx, const char *name, JSFunction *fun,
284 uintN indent, JSBool pretty);
285
286extern void
287js_DestroyPrinter(JSPrinter *jp);
288
289extern JSString *
290js_GetPrinterOutput(JSPrinter *jp);
291
292extern int
293js_printf(JSPrinter *jp, const char *format, ...);
294
295extern JSBool
296js_puts(JSPrinter *jp, const char *s);
297
298/*
299 * Get index operand from the bytecode using a bytecode analysis to deduce the
300 * the index register. This function is infallible, in spite of taking cx as
301 * its first parameter; it uses only cx->runtime when calling JS_GetTrapOpcode.
302 * The GET_*_FROM_BYTECODE macros that call it pick up cx from their caller's
303 * lexical environments.
304 */
305uintN
306js_GetIndexFromBytecode(JSContext *cx, JSScript *script, jsbytecode *pc,
307 ptrdiff_t pcoff);
308
309/*
310 * A slower version of GET_ATOM when the caller does not want to maintain
311 * the index segment register itself.
312 */
313#define GET_ATOM_FROM_BYTECODE(script, pc, pcoff, atom) \
314 JS_BEGIN_MACRO \
315 uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \
316 JS_GET_SCRIPT_ATOM((script), index_, atom); \
317 JS_END_MACRO
318
319#define GET_OBJECT_FROM_BYTECODE(script, pc, pcoff, obj) \
320 JS_BEGIN_MACRO \
321 uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \
322 JS_GET_SCRIPT_OBJECT((script), index_, obj); \
323 JS_END_MACRO
324
325#define GET_FUNCTION_FROM_BYTECODE(script, pc, pcoff, fun) \
326 JS_BEGIN_MACRO \
327 uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \
328 JS_GET_SCRIPT_FUNCTION((script), index_, fun); \
329 JS_END_MACRO
330
331#define GET_REGEXP_FROM_BYTECODE(script, pc, pcoff, obj) \
332 JS_BEGIN_MACRO \
333 uintN index_ = js_GetIndexFromBytecode(cx, (script), (pc), (pcoff)); \
334 JS_GET_SCRIPT_REGEXP((script), index_, obj); \
335 JS_END_MACRO
336
337/*
338 * Get the length of variable-length bytecode like JSOP_TABLESWITCH.
339 */
340extern uintN
341js_GetVariableBytecodeLength(jsbytecode *pc);
342
343/*
344 * Find the number of stack slots used by a variadic opcode such as JSOP_CALL
345 * or JSOP_NEWARRAY (for such ops, JSCodeSpec.nuses is -1).
346 */
347extern uintN
348js_GetVariableStackUseLength(JSOp op, jsbytecode *pc);
349
350#ifdef DEBUG
351/*
352 * Disassemblers, for debugging only.
353 */
354#include <stdio.h>
355
356extern JS_FRIEND_API(JSBool)
357js_Disassemble(JSContext *cx, JSScript *script, JSBool lines, FILE *fp);
358
359extern JS_FRIEND_API(uintN)
360js_Disassemble1(JSContext *cx, JSScript *script, jsbytecode *pc, uintN loc,
361 JSBool lines, FILE *fp);
362#endif /* DEBUG */
363
364/*
365 * Decompilers, for script, function, and expression pretty-printing.
366 */
367extern JSBool
368js_DecompileScript(JSPrinter *jp, JSScript *script);
369
370extern JSBool
371js_DecompileFunctionBody(JSPrinter *jp);
372
373extern JSBool
374js_DecompileFunction(JSPrinter *jp);
375
376/*
377 * Find the source expression that resulted in v, and return a newly allocated
378 * C-string containing it. Fall back on v's string conversion (fallback) if we
379 * can't find the bytecode that generated and pushed v on the operand stack.
380 *
381 * Search the current stack frame if spindex is JSDVG_SEARCH_STACK. Don't
382 * look for v on the stack if spindex is JSDVG_IGNORE_STACK. Otherwise,
383 * spindex is the negative index of v, measured from cx->fp->sp, or from a
384 * lower frame's sp if cx->fp is native.
385 *
386 * The caller must call JS_free on the result after a succsesful call.
387 */
388extern char *
389js_DecompileValueGenerator(JSContext *cx, intN spindex, jsval v,
390 JSString *fallback);
391
392#define JSDVG_IGNORE_STACK 0
393#define JSDVG_SEARCH_STACK 1
394
395/*
396 * Given bytecode address pc in script's main program code, return the operand
397 * stack depth just before (JSOp) *pc executes.
398 */
399extern uintN
400js_ReconstructStackDepth(JSContext *cx, JSScript *script, jsbytecode *pc);
401
402JS_END_EXTERN_C
403
404#endif /* jsopcode_h___ */