Merge mozilla-central and tracemonkey. (a=blockers)
[mozilla-central.git] / js / src / jsnum.h
blob9548cf537f772a6abf73e949d5d312f6c8742368
1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
3 * ***** BEGIN LICENSE BLOCK *****
4 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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/
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.
16 * The Original Code is Mozilla Communicator client code, released
17 * March 31, 1998.
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.
24 * Contributor(s):
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.
38 * ***** END LICENSE BLOCK ***** */
40 #ifndef jsnum_h___
41 #define jsnum_h___
43 #include <math.h>
44 #if defined(XP_WIN) || defined(XP_OS2)
45 #include <float.h>
46 #endif
47 #ifdef SOLARIS
48 #include <ieeefp.h>
49 #endif
50 #include "jsvalue.h"
52 #include "jsstdint.h"
53 #include "jsstr.h"
54 #include "jsobj.h"
57 * JS number (IEEE double) interface.
59 * JS numbers are optimistically stored in the top 31 bits of 32-bit integers,
60 * but floating point literals, results that overflow 31 bits, and division and
61 * modulus operands and results require a 64-bit IEEE double. These are GC'ed
62 * and pointed to by 32-bit jsvals on the stack and in object properties.
66 * The ARM architecture supports two floating point models: VFP and FPA. When
67 * targetting FPA, doubles are mixed-endian on little endian ARMs (meaning that
68 * the high and low words are in big endian order).
70 #if defined(__arm) || defined(__arm32__) || defined(__arm26__) || defined(__arm__)
71 #if !defined(__VFP_FP__)
72 #define FPU_IS_ARM_FPA
73 #endif
74 #endif
76 typedef union jsdpun {
77 struct {
78 #if defined(IS_LITTLE_ENDIAN) && !defined(FPU_IS_ARM_FPA)
79 uint32 lo, hi;
80 #else
81 uint32 hi, lo;
82 #endif
83 } s;
84 uint64 u64;
85 jsdouble d;
86 } jsdpun;
88 static inline int
89 JSDOUBLE_IS_NaN(jsdouble d)
91 #ifdef WIN32
92 return _isnan(d);
93 #else
94 return isnan(d);
95 #endif
98 static inline int
99 JSDOUBLE_IS_FINITE(jsdouble d)
101 #ifdef WIN32
102 return _finite(d);
103 #else
104 return finite(d);
105 #endif
108 static inline int
109 JSDOUBLE_IS_INFINITE(jsdouble d)
111 #ifdef WIN32
112 int c = _fpclass(d);
113 return c == _FPCLASS_NINF || c == _FPCLASS_PINF;
114 #elif defined(SOLARIS)
115 return !finite(d) && !isnan(d);
116 #else
117 return isinf(d);
118 #endif
121 #define JSDOUBLE_HI32_SIGNBIT 0x80000000
122 #define JSDOUBLE_HI32_EXPMASK 0x7ff00000
123 #define JSDOUBLE_HI32_MANTMASK 0x000fffff
124 #define JSDOUBLE_HI32_NAN 0x7ff80000
125 #define JSDOUBLE_LO32_NAN 0x00000000
127 static inline bool
128 JSDOUBLE_IS_NEG(jsdouble d)
130 #ifdef WIN32
131 return JSDOUBLE_IS_NEGZERO(d) || d < 0;
132 #elif defined(SOLARIS)
133 return copysign(1, d) < 0;
134 #else
135 return signbit(d);
136 #endif
139 static inline uint32
140 JS_HASH_DOUBLE(jsdouble d)
142 jsdpun u;
143 u.d = d;
144 return u.s.lo ^ u.s.hi;
147 #if defined(XP_WIN)
148 #define JSDOUBLE_COMPARE(LVAL, OP, RVAL, IFNAN) \
149 ((JSDOUBLE_IS_NaN(LVAL) || JSDOUBLE_IS_NaN(RVAL)) \
150 ? (IFNAN) \
151 : (LVAL) OP (RVAL))
152 #else
153 #define JSDOUBLE_COMPARE(LVAL, OP, RVAL, IFNAN) ((LVAL) OP (RVAL))
154 #endif
156 extern jsdouble js_NaN;
157 extern jsdouble js_PositiveInfinity;
158 extern jsdouble js_NegativeInfinity;
160 /* Initialize number constants and runtime state for the first context. */
161 extern JSBool
162 js_InitRuntimeNumberState(JSContext *cx);
164 extern void
165 js_FinishRuntimeNumberState(JSContext *cx);
167 /* Initialize the Number class, returning its prototype object. */
168 extern js::Class js_NumberClass;
170 inline bool
171 JSObject::isNumber() const
173 return getClass() == &js_NumberClass;
176 extern JSObject *
177 js_InitNumberClass(JSContext *cx, JSObject *obj);
180 * String constants for global function names, used in jsapi.c and jsnum.c.
182 extern const char js_Infinity_str[];
183 extern const char js_NaN_str[];
184 extern const char js_isNaN_str[];
185 extern const char js_isFinite_str[];
186 extern const char js_parseFloat_str[];
187 extern const char js_parseInt_str[];
189 extern JSString * JS_FASTCALL
190 js_IntToString(JSContext *cx, jsint i);
193 * When base == 10, this function implements ToString() as specified by
194 * ECMA-262-5 section 9.8.1; but note that it handles integers specially for
195 * performance. See also js::NumberToCString().
197 extern JSString * JS_FASTCALL
198 js_NumberToString(JSContext *cx, jsdouble d);
200 namespace js {
203 * Convert an integer or double (contained in the given value) to a string and
204 * append to the given buffer.
206 extern bool JS_FASTCALL
207 NumberValueToStringBuffer(JSContext *cx, const Value &v, StringBuffer &sb);
209 /* Same as js_NumberToString, different signature. */
210 extern JSFlatString *
211 NumberToString(JSContext *cx, jsdouble d);
214 * Usually a small amount of static storage is enough, but sometimes we need
215 * to dynamically allocate much more. This struct encapsulates that.
216 * Dynamically allocated memory will be freed when the object is destroyed.
218 struct ToCStringBuf
221 * The longest possible result that would need to fit in sbuf is
222 * (-0x80000000).toString(2), which has length 33. Longer cases are
223 * possible, but they'll go in dbuf.
225 static const size_t sbufSize = 34;
226 char sbuf[sbufSize];
227 char *dbuf; /* must be allocated with js_malloc() */
229 ToCStringBuf();
230 ~ToCStringBuf();
234 * Convert a number to a C string. When base==10, this function implements
235 * ToString() as specified by ECMA-262-5 section 9.8.1. It handles integral
236 * values cheaply. Return NULL if we ran out of memory. See also
237 * js_NumberToCString().
239 extern char *
240 NumberToCString(JSContext *cx, ToCStringBuf *cbuf, jsdouble d, jsint base = 10);
243 * The largest positive integer such that all positive integers less than it
244 * may be precisely represented using the IEEE-754 double-precision format.
246 const double DOUBLE_INTEGRAL_PRECISION_LIMIT = uint64(1) << 53;
249 * Compute the positive integer of the given base described immediately at the
250 * start of the range [start, end) -- no whitespace-skipping, no magical
251 * leading-"0" octal or leading-"0x" hex behavior, no "+"/"-" parsing, just
252 * reading the digits of the integer. Return the index one past the end of the
253 * digits of the integer in *endp, and return the integer itself in *dp. If
254 * base is 10 or a power of two the returned integer is the closest possible
255 * double; otherwise extremely large integers may be slightly inaccurate.
257 * If [start, end) does not begin with a number with the specified base,
258 * *dp == 0 and *endp == start upon return.
260 extern bool
261 GetPrefixInteger(JSContext *cx, const jschar *start, const jschar *end, int base,
262 const jschar **endp, jsdouble *dp);
265 * Convert a value to a number, returning the converted value in 'out' if the
266 * conversion succeeds.
268 JS_ALWAYS_INLINE bool
269 ValueToNumber(JSContext *cx, const js::Value &v, double *out)
271 if (v.isNumber()) {
272 *out = v.toNumber();
273 return true;
275 extern bool ValueToNumberSlow(JSContext *, js::Value, double *);
276 return ValueToNumberSlow(cx, v, out);
279 /* Convert a value to a number, replacing 'vp' with the converted value. */
280 JS_ALWAYS_INLINE bool
281 ValueToNumber(JSContext *cx, js::Value *vp)
283 if (vp->isNumber())
284 return true;
285 double d;
286 extern bool ValueToNumberSlow(JSContext *, js::Value, double *);
287 if (!ValueToNumberSlow(cx, *vp, &d))
288 return false;
289 vp->setNumber(d);
290 return true;
294 * Convert a value to an int32 or uint32, according to the ECMA rules for
295 * ToInt32 and ToUint32. Return converted value in *out on success, !ok on
296 * failure.
298 JS_ALWAYS_INLINE bool
299 ValueToECMAInt32(JSContext *cx, const js::Value &v, int32_t *out)
301 if (v.isInt32()) {
302 *out = v.toInt32();
303 return true;
305 extern bool ValueToECMAInt32Slow(JSContext *, const js::Value &, int32_t *);
306 return ValueToECMAInt32Slow(cx, v, out);
309 JS_ALWAYS_INLINE bool
310 ValueToECMAUint32(JSContext *cx, const js::Value &v, uint32_t *out)
312 if (v.isInt32()) {
313 *out = (uint32_t)v.toInt32();
314 return true;
316 extern bool ValueToECMAUint32Slow(JSContext *, const js::Value &, uint32_t *);
317 return ValueToECMAUint32Slow(cx, v, out);
321 * Convert a value to a number, then to an int32 if it fits by rounding to
322 * nearest. Return converted value in *out on success, !ok on failure. As a
323 * side effect, *vp will be mutated to match *out.
325 JS_ALWAYS_INLINE bool
326 ValueToInt32(JSContext *cx, const js::Value &v, int32_t *out)
328 if (v.isInt32()) {
329 *out = v.toInt32();
330 return true;
332 extern bool ValueToInt32Slow(JSContext *, const js::Value &, int32_t *);
333 return ValueToInt32Slow(cx, v, out);
337 * Convert a value to a number, then to a uint16 according to the ECMA rules
338 * for ToUint16. Return converted value on success, !ok on failure. v must be a
339 * copy of a rooted value.
341 JS_ALWAYS_INLINE bool
342 ValueToUint16(JSContext *cx, const js::Value &v, uint16_t *out)
344 if (v.isInt32()) {
345 *out = (uint16_t)v.toInt32();
346 return true;
348 extern bool ValueToUint16Slow(JSContext *, const js::Value &, uint16_t *);
349 return ValueToUint16Slow(cx, v, out);
352 } /* namespace js */
355 * Specialized ToInt32 and ToUint32 converters for doubles.
358 * From the ES3 spec, 9.5
359 * 2. If Result(1) is NaN, +0, -0, +Inf, or -Inf, return +0.
360 * 3. Compute sign(Result(1)) * floor(abs(Result(1))).
361 * 4. Compute Result(3) modulo 2^32; that is, a finite integer value k of Number
362 * type with positive sign and less than 2^32 in magnitude such the mathematical
363 * difference of Result(3) and k is mathematically an integer multiple of 2^32.
364 * 5. If Result(4) is greater than or equal to 2^31, return Result(4)- 2^32,
365 * otherwise return Result(4).
367 static inline int32
368 js_DoubleToECMAInt32(jsdouble d)
370 #if defined(__i386__) || defined(__i386) || defined(__x86_64__) || \
371 defined(_M_IX86) || defined(_M_X64)
372 jsdpun du, duh, two32;
373 uint32 di_h, u_tmp, expon, shift_amount;
374 int32 mask32;
377 * Algorithm Outline
378 * Step 1. If d is NaN, +/-Inf or |d|>=2^84 or |d|<1, then return 0
379 * All of this is implemented based on an exponent comparison.
380 * Step 2. If |d|<2^31, then return (int)d
381 * The cast to integer (conversion in RZ mode) returns the correct result.
382 * Step 3. If |d|>=2^32, d:=fmod(d, 2^32) is taken -- but without a call
383 * Step 4. If |d|>=2^31, then the fractional bits are cleared before
384 * applying the correction by 2^32: d - sign(d)*2^32
385 * Step 5. Return (int)d
388 du.d = d;
389 di_h = du.s.hi;
391 u_tmp = (di_h & 0x7ff00000) - 0x3ff00000;
392 if (u_tmp >= (0x45300000-0x3ff00000)) {
393 // d is Nan, +/-Inf or +/-0, or |d|>=2^(32+52) or |d|<1, in which case result=0
394 return 0;
397 if (u_tmp < 0x01f00000) {
398 // |d|<2^31
399 return int32_t(d);
402 if (u_tmp > 0x01f00000) {
403 // |d|>=2^32
404 expon = u_tmp >> 20;
405 shift_amount = expon - 21;
406 duh.u64 = du.u64;
407 mask32 = 0x80000000;
408 if (shift_amount < 32) {
409 mask32 >>= shift_amount;
410 duh.s.hi = du.s.hi & mask32;
411 duh.s.lo = 0;
412 } else {
413 mask32 >>= (shift_amount-32);
414 duh.s.hi = du.s.hi;
415 duh.s.lo = du.s.lo & mask32;
417 du.d -= duh.d;
420 di_h = du.s.hi;
422 // eliminate fractional bits
423 u_tmp = (di_h & 0x7ff00000);
424 if (u_tmp >= 0x41e00000) {
425 // |d|>=2^31
426 expon = u_tmp >> 20;
427 shift_amount = expon - (0x3ff - 11);
428 mask32 = 0x80000000;
429 if (shift_amount < 32) {
430 mask32 >>= shift_amount;
431 du.s.hi &= mask32;
432 du.s.lo = 0;
433 } else {
434 mask32 >>= (shift_amount-32);
435 du.s.lo &= mask32;
437 two32.s.hi = 0x41f00000 ^ (du.s.hi & 0x80000000);
438 two32.s.lo = 0;
439 du.d -= two32.d;
442 return int32(du.d);
443 #elif defined (__arm__) && defined (__GNUC__)
444 int32_t i;
445 uint32_t tmp0;
446 uint32_t tmp1;
447 uint32_t tmp2;
448 asm (
449 // We use a pure integer solution here. In the 'softfp' ABI, the argument
450 // will start in r0 and r1, and VFP can't do all of the necessary ECMA
451 // conversions by itself so some integer code will be required anyway. A
452 // hybrid solution is faster on A9, but this pure integer solution is
453 // notably faster for A8.
455 // %0 is the result register, and may alias either of the %[QR]1 registers.
456 // %Q4 holds the lower part of the mantissa.
457 // %R4 holds the sign, exponent, and the upper part of the mantissa.
458 // %1, %2 and %3 are used as temporary values.
460 // Extract the exponent.
461 " mov %1, %R4, LSR #20\n"
462 " bic %1, %1, #(1 << 11)\n" // Clear the sign.
464 // Set the implicit top bit of the mantissa. This clobbers a bit of the
465 // exponent, but we have already extracted that.
466 " orr %R4, %R4, #(1 << 20)\n"
468 // Special Cases
469 // We should return zero in the following special cases:
470 // - Exponent is 0x000 - 1023: +/-0 or subnormal.
471 // - Exponent is 0x7ff - 1023: +/-INFINITY or NaN
472 // - This case is implicitly handled by the standard code path anyway,
473 // as shifting the mantissa up by the exponent will result in '0'.
475 // The result is composed of the mantissa, prepended with '1' and
476 // bit-shifted left by the (decoded) exponent. Note that because the r1[20]
477 // is the bit with value '1', r1 is effectively already shifted (left) by
478 // 20 bits, and r0 is already shifted by 52 bits.
480 // Adjust the exponent to remove the encoding offset. If the decoded
481 // exponent is negative, quickly bail out with '0' as such values round to
482 // zero anyway. This also catches +/-0 and subnormals.
483 " sub %1, %1, #0xff\n"
484 " subs %1, %1, #0x300\n"
485 " bmi 8f\n"
487 // %1 = (decoded) exponent >= 0
488 // %R4 = upper mantissa and sign
490 // ---- Lower Mantissa ----
491 " subs %3, %1, #52\n" // Calculate exp-52
492 " bmi 1f\n"
494 // Shift r0 left by exp-52.
495 // Ensure that we don't overflow ARM's 8-bit shift operand range.
496 // We need to handle anything up to an 11-bit value here as we know that
497 // 52 <= exp <= 1024 (0x400). Any shift beyond 31 bits results in zero
498 // anyway, so as long as we don't touch the bottom 5 bits, we can use
499 // a logical OR to push long shifts into the 32 <= (exp&0xff) <= 255 range.
500 " bic %2, %3, #0xff\n"
501 " orr %3, %3, %2, LSR #3\n"
502 // We can now perform a straight shift, avoiding the need for any
503 // conditional instructions or extra branches.
504 " mov %Q4, %Q4, LSL %3\n"
505 " b 2f\n"
506 "1:\n" // Shift r0 right by 52-exp.
507 // We know that 0 <= exp < 52, and we can shift up to 255 bits so 52-exp
508 // will always be a valid shift and we can sk%3 the range check for this case.
509 " rsb %3, %1, #52\n"
510 " mov %Q4, %Q4, LSR %3\n"
512 // %1 = (decoded) exponent
513 // %R4 = upper mantissa and sign
514 // %Q4 = partially-converted integer
516 "2:\n"
517 // ---- Upper Mantissa ----
518 // This is much the same as the lower mantissa, with a few different
519 // boundary checks and some masking to hide the exponent & sign bit in the
520 // upper word.
521 // Note that the upper mantissa is pre-shifted by 20 in %R4, but we shift
522 // it left more to remove the sign and exponent so it is effectively
523 // pre-shifted by 31 bits.
524 " subs %3, %1, #31\n" // Calculate exp-31
525 " mov %1, %R4, LSL #11\n" // Re-use %1 as a temporary register.
526 " bmi 3f\n"
528 // Shift %R4 left by exp-31.
529 // Avoid overflowing the 8-bit shift range, as before.
530 " bic %2, %3, #0xff\n"
531 " orr %3, %3, %2, LSR #3\n"
532 // Perform the shift.
533 " mov %2, %1, LSL %3\n"
534 " b 4f\n"
535 "3:\n" // Shift r1 right by 31-exp.
536 // We know that 0 <= exp < 31, and we can shift up to 255 bits so 31-exp
537 // will always be a valid shift and we can skip the range check for this case.
538 " rsb %3, %3, #0\n" // Calculate 31-exp from -(exp-31)
539 " mov %2, %1, LSR %3\n" // Thumb-2 can't do "LSR %3" in "orr".
541 // %Q4 = partially-converted integer (lower)
542 // %R4 = upper mantissa and sign
543 // %2 = partially-converted integer (upper)
545 "4:\n"
546 // Combine the converted parts.
547 " orr %Q4, %Q4, %2\n"
548 // Negate the result if we have to, and move it to %0 in the process. To
549 // avoid conditionals, we can do this by inverting on %R4[31], then adding
550 // %R4[31]>>31.
551 " eor %Q4, %Q4, %R4, ASR #31\n"
552 " add %0, %Q4, %R4, LSR #31\n"
553 " b 9f\n"
554 "8:\n"
555 // +/-INFINITY, +/-0, subnormals, NaNs, and anything else out-of-range that
556 // will result in a conversion of '0'.
557 " mov %0, #0\n"
558 "9:\n"
559 : "=r" (i), "=&r" (tmp0), "=&r" (tmp1), "=&r" (tmp2)
560 : "r" (d)
561 : "cc"
563 return i;
564 #else
565 int32 i;
566 jsdouble two32, two31;
568 if (!JSDOUBLE_IS_FINITE(d))
569 return 0;
571 i = (int32) d;
572 if ((jsdouble) i == d)
573 return i;
575 two32 = 4294967296.0;
576 two31 = 2147483648.0;
577 d = fmod(d, two32);
578 d = (d >= 0) ? floor(d) : ceil(d) + two32;
579 return (int32) (d >= two31 ? d - two32 : d);
580 #endif
583 uint32
584 js_DoubleToECMAUint32(jsdouble d);
587 * Convert a jsdouble to an integral number, stored in a jsdouble.
588 * If d is NaN, return 0. If d is an infinity, return it without conversion.
590 static inline jsdouble
591 js_DoubleToInteger(jsdouble d)
593 if (d == 0)
594 return d;
596 if (!JSDOUBLE_IS_FINITE(d)) {
597 if (JSDOUBLE_IS_NaN(d))
598 return 0;
599 return d;
602 JSBool neg = (d < 0);
603 d = floor(neg ? -d : d);
605 return neg ? -d : d;
609 * Similar to strtod except that it replaces overflows with infinities of the
610 * correct sign, and underflows with zeros of the correct sign. Guaranteed to
611 * return the closest double number to the given input in dp.
613 * Also allows inputs of the form [+|-]Infinity, which produce an infinity of
614 * the appropriate sign. The case of the "Infinity" string must match exactly.
615 * If the string does not contain a number, set *ep to s and return 0.0 in dp.
616 * Return false if out of memory.
618 extern JSBool
619 js_strtod(JSContext *cx, const jschar *s, const jschar *send,
620 const jschar **ep, jsdouble *dp);
622 extern JSBool
623 js_num_valueOf(JSContext *cx, uintN argc, js::Value *vp);
625 namespace js {
627 static JS_ALWAYS_INLINE bool
628 ValueFitsInInt32(const Value &v, int32_t *pi)
630 if (v.isInt32()) {
631 *pi = v.toInt32();
632 return true;
634 return v.isDouble() && JSDOUBLE_IS_INT32(v.toDouble(), pi);
637 template<typename T> struct NumberTraits { };
638 template<> struct NumberTraits<int32> {
639 static JS_ALWAYS_INLINE int32 NaN() { return 0; }
640 static JS_ALWAYS_INLINE int32 toSelfType(int32 i) { return i; }
641 static JS_ALWAYS_INLINE int32 toSelfType(jsdouble d) { return js_DoubleToECMAUint32(d); }
643 template<> struct NumberTraits<jsdouble> {
644 static JS_ALWAYS_INLINE jsdouble NaN() { return js_NaN; }
645 static JS_ALWAYS_INLINE jsdouble toSelfType(int32 i) { return i; }
646 static JS_ALWAYS_INLINE jsdouble toSelfType(jsdouble d) { return d; }
649 template<typename T>
650 static JS_ALWAYS_INLINE bool
651 StringToNumberType(JSContext *cx, JSString *str, T *result)
653 size_t length = str->length();
654 const jschar *chars = str->getChars(NULL);
655 if (!chars)
656 return false;
658 if (length == 1) {
659 jschar c = chars[0];
660 if ('0' <= c && c <= '9') {
661 *result = NumberTraits<T>::toSelfType(T(c - '0'));
662 return true;
664 if (JS_ISSPACE(c)) {
665 *result = NumberTraits<T>::toSelfType(T(0));
666 return true;
668 *result = NumberTraits<T>::NaN();
669 return true;
672 const jschar *bp = chars;
673 const jschar *end = chars + length;
674 bp = js_SkipWhiteSpace(bp, end);
676 /* ECMA doesn't allow signed hex numbers (bug 273467). */
677 if (end - bp >= 2 && bp[0] == '0' && (bp[1] == 'x' || bp[1] == 'X')) {
678 /* Looks like a hex number. */
679 const jschar *endptr;
680 double d;
681 if (!GetPrefixInteger(cx, bp + 2, end, 16, &endptr, &d) ||
682 js_SkipWhiteSpace(endptr, end) != end) {
683 *result = NumberTraits<T>::NaN();
684 return true;
686 *result = NumberTraits<T>::toSelfType(d);
687 return true;
691 * Note that ECMA doesn't treat a string beginning with a '0' as
692 * an octal number here. This works because all such numbers will
693 * be interpreted as decimal by js_strtod. Also, any hex numbers
694 * that have made it here (which can only be negative ones) will
695 * be treated as 0 without consuming the 'x' by js_strtod.
697 const jschar *ep;
698 double d;
699 if (!js_strtod(cx, bp, end, &ep, &d) || js_SkipWhiteSpace(ep, end) != end) {
700 *result = NumberTraits<T>::NaN();
701 return true;
703 *result = NumberTraits<T>::toSelfType(d);
704 return true;
708 #endif /* jsnum_h___ */