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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
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* ***** BEGIN LICENSE BLOCK *****
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* Version: MPL 1.1/GPL 2.0/LGPL 2.1
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* The contents of this file are subject to the Mozilla Public License Version
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* 1.1 (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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* http://www.mozilla.org/MPL/
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* Software distributed under the License is distributed on an "AS IS" basis,
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* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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* for the specific language governing rights and limitations under the
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* The Original Code is Mozilla Communicator client code, released
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* The Initial Developer of the Original Code is
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* Netscape Communications Corporation.
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* Portions created by the Initial Developer are Copyright (C) 1998
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* the Initial Developer. All Rights Reserved.
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* Alternatively, the contents of this file may be used under the terms of
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* either of the GNU General Public License Version 2 or later (the "GPL"),
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* or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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* in which case the provisions of the GPL or the LGPL are applicable instead
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* of those above. If you wish to allow use of your version of this file only
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* under the terms of either the GPL or the LGPL, and not to allow others to
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* use your version of this file under the terms of the MPL, indicate your
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* decision by deleting the provisions above and replace them with the notice
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* and other provisions required by the GPL or the LGPL. If you do not delete
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* the provisions above, a recipient may use your version of this file under
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* the terms of any one of the MPL, the GPL or the LGPL.
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* ***** END LICENSE BLOCK ***** */
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* JS number (IEEE double) interface.
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* JS numbers are optimistically stored in the top 31 bits of 32-bit integers,
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* but floating point literals, results that overflow 31 bits, and division and
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* modulus operands and results require a 64-bit IEEE double. These are GC'ed
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* and pointed to by 32-bit jsvals on the stack and in object properties.
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* When a JS number is treated as an object (followed by . or []), the runtime
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* wraps it with a JSObject whose valueOf method returns the unwrapped number.
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* Stefan Hanske <sh990154@mail.uni-greifswald.de> reports:
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* ARM is a little endian architecture but 64 bit double words are stored
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* differently: the 32 bit words are in little endian byte order, the two words
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* are stored in big endian`s way.
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#if defined(__arm) || defined(__arm32__) || defined(__arm26__) || defined(__arm__)
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typedef union jsdpun {
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#if defined(IS_LITTLE_ENDIAN) && !defined(CPU_IS_ARM)
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#if (__GNUC__ == 2 && __GNUC_MINOR__ > 95) || __GNUC__ > 2
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* This version of the macros is safe for the alias optimizations that gcc
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* does, but uses gcc-specific extensions.
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#define JSDOUBLE_HI32(x) (__extension__ ({ jsdpun u; u.d = (x); u.s.hi; }))
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#define JSDOUBLE_LO32(x) (__extension__ ({ jsdpun u; u.d = (x); u.s.lo; }))
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#define JSDOUBLE_SET_HI32(x, y) \
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(__extension__ ({ jsdpun u; u.d = (x); u.s.hi = (y); (x) = u.d; }))
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#define JSDOUBLE_SET_LO32(x, y) \
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(__extension__ ({ jsdpun u; u.d = (x); u.s.lo = (y); (x) = u.d; }))
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#else /* not or old GNUC */
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* We don't know of any non-gcc compilers that perform alias optimization,
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* so this code should work.
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#if defined(IS_LITTLE_ENDIAN) && !defined(CPU_IS_ARM)
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#define JSDOUBLE_HI32(x) (((uint32 *)&(x))[1])
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#define JSDOUBLE_LO32(x) (((uint32 *)&(x))[0])
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#define JSDOUBLE_HI32(x) (((uint32 *)&(x))[0])
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#define JSDOUBLE_LO32(x) (((uint32 *)&(x))[1])
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#define JSDOUBLE_SET_HI32(x, y) (JSDOUBLE_HI32(x)=(y))
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#define JSDOUBLE_SET_LO32(x, y) (JSDOUBLE_LO32(x)=(y))
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#endif /* not or old GNUC */
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#define JSDOUBLE_HI32_SIGNBIT 0x80000000
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#define JSDOUBLE_HI32_EXPMASK 0x7ff00000
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#define JSDOUBLE_HI32_MANTMASK 0x000fffff
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#define JSDOUBLE_IS_NaN(x) \
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((JSDOUBLE_HI32(x) & JSDOUBLE_HI32_EXPMASK) == JSDOUBLE_HI32_EXPMASK && \
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(JSDOUBLE_LO32(x) || (JSDOUBLE_HI32(x) & JSDOUBLE_HI32_MANTMASK)))
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#define JSDOUBLE_IS_INFINITE(x) \
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((JSDOUBLE_HI32(x) & ~JSDOUBLE_HI32_SIGNBIT) == JSDOUBLE_HI32_EXPMASK && \
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#define JSDOUBLE_IS_FINITE(x) \
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((JSDOUBLE_HI32(x) & JSDOUBLE_HI32_EXPMASK) != JSDOUBLE_HI32_EXPMASK)
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#define JSDOUBLE_IS_NEGZERO(d) (JSDOUBLE_HI32(d) == JSDOUBLE_HI32_SIGNBIT && \
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JSDOUBLE_LO32(d) == 0)
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* JSDOUBLE_IS_INT first checks that d is neither NaN nor infinite, to avoid
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* raising SIGFPE on platforms such as Alpha Linux, then (only if the cast is
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* safe) leaves i as (jsint)d. This also avoid anomalous NaN floating point
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* comparisons under MSVC.
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#define JSDOUBLE_IS_INT(d, i) (JSDOUBLE_IS_FINITE(d) \
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&& !JSDOUBLE_IS_NEGZERO(d) \
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&& ((d) == (i = (jsint)(d))))
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#define JSDOUBLE_COMPARE(LVAL, OP, RVAL, IFNAN) \
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((JSDOUBLE_IS_NaN(LVAL) || JSDOUBLE_IS_NaN(RVAL)) \
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#define JSDOUBLE_COMPARE(LVAL, OP, RVAL, IFNAN) ((LVAL) OP (RVAL))
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/* Initialize number constants and runtime state for the first context. */
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js_InitRuntimeNumberState(JSContext *cx);
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js_FinishRuntimeNumberState(JSContext *cx);
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/* Initialize the Number class, returning its prototype object. */
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extern JSClass js_NumberClass;
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js_InitNumberClass(JSContext *cx, JSObject *obj);
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* String constants for global function names, used in jsapi.c and jsnum.c.
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extern const char js_Infinity_str[];
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extern const char js_NaN_str[];
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extern const char js_isNaN_str[];
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extern const char js_isFinite_str[];
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extern const char js_parseFloat_str[];
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extern const char js_parseInt_str[];
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/* GC-allocate a new JS number. */
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js_NewDouble(JSContext *cx, jsdouble d, uintN gcflag);
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js_FinalizeDouble(JSContext *cx, jsdouble *dp);
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js_NewDoubleValue(JSContext *cx, jsdouble d, jsval *rval);
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js_NewNumberValue(JSContext *cx, jsdouble d, jsval *rval);
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/* Construct a Number instance that wraps around d. */
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js_NumberToObject(JSContext *cx, jsdouble d);
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/* Convert a number to a GC'ed string. */
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js_NumberToString(JSContext *cx, jsdouble d);
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* Convert a value to a number, returning false after reporting any error,
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* otherwise returning true with *dp set.
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js_ValueToNumber(JSContext *cx, jsval v, jsdouble *dp);
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* Convert a value or a double to an int32, according to the ECMA rules
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js_ValueToECMAInt32(JSContext *cx, jsval v, int32 *ip);
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js_DoubleToECMAInt32(JSContext *cx, jsdouble d, int32 *ip);
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* Convert a value or a double to a uint32, according to the ECMA rules
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js_ValueToECMAUint32(JSContext *cx, jsval v, uint32 *ip);
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js_DoubleToECMAUint32(JSContext *cx, jsdouble d, uint32 *ip);
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* Convert a value to a number, then to an int32 if it fits by rounding to
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* nearest; but failing with an error report if the double is out of range
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js_ValueToInt32(JSContext *cx, jsval v, int32 *ip);
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* Convert a value to a number, then to a uint16 according to the ECMA rules
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js_ValueToUint16(JSContext *cx, jsval v, uint16 *ip);
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* Convert a jsdouble to an integral number, stored in a jsdouble.
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* If d is NaN, return 0. If d is an infinity, return it without conversion.
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js_DoubleToInteger(jsdouble d);
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* Similar to strtod except that it replaces overflows with infinities of the
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* correct sign, and underflows with zeros of the correct sign. Guaranteed to
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* return the closest double number to the given input in dp.
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* Also allows inputs of the form [+|-]Infinity, which produce an infinity of
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* the appropriate sign. The case of the "Infinity" string must match exactly.
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* If the string does not contain a number, set *ep to s and return 0.0 in dp.
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* Return false if out of memory.
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js_strtod(JSContext *cx, const jschar *s, const jschar **ep, jsdouble *dp);
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* Similar to strtol except that it handles integers of arbitrary size.
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* Guaranteed to return the closest double number to the given input when radix
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* is 10 or a power of 2. Callers may see round-off errors for very large
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* numbers of a different radix than 10 or a power of 2.
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* If the string does not contain a number, set *ep to s and return 0.0 in dp.
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* Return false if out of memory.
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js_strtointeger(JSContext *cx, const jschar *s, const jschar **ep, jsint radix, jsdouble *dp);
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#endif /* jsnum_h___ */