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*** 0 ****
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+ /* -*- 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 ***** */
+
+ /*
+ * Portable double to alphanumeric string and back converters.
+ */
+ #include "jsstddef.h"
+ #include "jslibmath.h"
+ #include "jstypes.h"
+ #include "jsdtoa.h"
+ #include "jsprf.h"
+ #include "jsutil.h" /* Added by JSIFY */
+ #include "jspubtd.h"
+ #include "jsnum.h"
+
+ #ifdef JS_THREADSAFE
+ #include "prlock.h"
+ #endif
+
+ /****************************************************************
+ *
+ * The author of this software is David M. Gay.
+ *
+ * Copyright (c) 1991 by Lucent Technologies.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose without fee is hereby granted, provided that this entire notice
+ * is included in all copies of any software which is or includes a copy
+ * or modification of this software and in all copies of the supporting
+ * documentation for such software.
+ *
+ * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTY. IN PARTICULAR, NEITHER THE AUTHOR NOR LUCENT MAKES ANY
+ * REPRESENTATION OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY
+ * OF THIS SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE.
+ *
+ ***************************************************************/
+
+ /* Please send bug reports to
+ David M. Gay
+ Bell Laboratories, Room 2C-463
+ 600 Mountain Avenue
+ Murray Hill, NJ 07974-0636
+ U.S.A.
+ dmg@bell-labs.com
+ */
+
+ /* On a machine with IEEE extended-precision registers, it is
+ * necessary to specify double-precision (53-bit) rounding precision
+ * before invoking strtod or dtoa. If the machine uses (the equivalent
+ * of) Intel 80x87 arithmetic, the call
+ * _control87(PC_53, MCW_PC);
+ * does this with many compilers. Whether this or another call is
+ * appropriate depends on the compiler; for this to work, it may be
+ * necessary to #include "float.h" or another system-dependent header
+ * file.
+ */
+
+ /* strtod for IEEE-arithmetic machines.
+ *
+ * This strtod returns a nearest machine number to the input decimal
+ * string (or sets err to JS_DTOA_ERANGE or JS_DTOA_ENOMEM). With IEEE
+ * arithmetic, ties are broken by the IEEE round-even rule. Otherwise
+ * ties are broken by biased rounding (add half and chop).
+ *
+ * Inspired loosely by William D. Clinger's paper "How to Read Floating
+ * Point Numbers Accurately" [Proc. ACM SIGPLAN '90, pp. 92-101].
+ *
+ * Modifications:
+ *
+ * 1. We only require IEEE double-precision
+ * arithmetic (not IEEE double-extended).
+ * 2. We get by with floating-point arithmetic in a case that
+ * Clinger missed -- when we're computing d * 10^n
+ * for a small integer d and the integer n is not too
+ * much larger than 22 (the maximum integer k for which
+ * we can represent 10^k exactly), we may be able to
+ * compute (d*10^k) * 10^(e-k) with just one roundoff.
+ * 3. Rather than a bit-at-a-time adjustment of the binary
+ * result in the hard case, we use floating-point
+ * arithmetic to determine the adjustment to within
+ * one bit; only in really hard cases do we need to
+ * compute a second residual.
+ * 4. Because of 3., we don't need a large table of powers of 10
+ * for ten-to-e (just some small tables, e.g. of 10^k
+ * for 0 <= k <= 22).
+ */
+
+ /*
+ * #define IEEE_8087 for IEEE-arithmetic machines where the least
+ * significant byte has the lowest address.
+ * #define IEEE_MC68k for IEEE-arithmetic machines where the most
+ * significant byte has the lowest address.
+ * #define Long int on machines with 32-bit ints and 64-bit longs.
+ * #define Sudden_Underflow for IEEE-format machines without gradual
+ * underflow (i.e., that flush to zero on underflow).
+ * #define No_leftright to omit left-right logic in fast floating-point
+ * computation of js_dtoa.
+ * #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3.
+ * #define RND_PRODQUOT to use rnd_prod and rnd_quot (assembly routines
+ * that use extended-precision instructions to compute rounded
+ * products and quotients) with IBM.
+ * #define ROUND_BIASED for IEEE-format with biased rounding.
+ * #define Inaccurate_Divide for IEEE-format with correctly rounded
+ * products but inaccurate quotients, e.g., for Intel i860.
+ * #define JS_HAVE_LONG_LONG on machines that have a "long long"
+ * integer type (of >= 64 bits). If long long is available and the name is
+ * something other than "long long", #define Llong to be the name,
+ * and if "unsigned Llong" does not work as an unsigned version of
+ * Llong, #define #ULLong to be the corresponding unsigned type.
+ * #define Bad_float_h if your system lacks a float.h or if it does not
+ * define some or all of DBL_DIG, DBL_MAX_10_EXP, DBL_MAX_EXP,
+ * FLT_RADIX, FLT_ROUNDS, and DBL_MAX.
+ * #define MALLOC your_malloc, where your_malloc(n) acts like malloc(n)
+ * if memory is available and otherwise does something you deem
+ * appropriate. If MALLOC is undefined, malloc will be invoked
+ * directly -- and assumed always to succeed.
+ * #define Omit_Private_Memory to omit logic (added Jan. 1998) for making
+ * memory allocations from a private pool of memory when possible.
+ * When used, the private pool is PRIVATE_MEM bytes long: 2000 bytes,
+ * unless #defined to be a different length. This default length
+ * suffices to get rid of MALLOC calls except for unusual cases,
+ * such as decimal-to-binary conversion of a very long string of
+ * digits.
+ * #define INFNAN_CHECK on IEEE systems to cause strtod to check for
+ * Infinity and NaN (case insensitively). On some systems (e.g.,
+ * some HP systems), it may be necessary to #define NAN_WORD0
+ * appropriately -- to the most significant word of a quiet NaN.
+ * (On HP Series 700/800 machines, -DNAN_WORD0=0x7ff40000 works.)
+ * #define MULTIPLE_THREADS if the system offers preemptively scheduled
+ * multiple threads. In this case, you must provide (or suitably
+ * #define) two locks, acquired by ACQUIRE_DTOA_LOCK() and released
+ * by RELEASE_DTOA_LOCK(). (The second lock, accessed
+ * in pow5mult, ensures lazy evaluation of only one copy of high
+ * powers of 5; omitting this lock would introduce a small
+ * probability of wasting memory, but would otherwise be harmless.)
+ * You must also invoke freedtoa(s) to free the value s returned by
+ * dtoa. You may do so whether or not MULTIPLE_THREADS is #defined.
+ * #define NO_IEEE_Scale to disable new (Feb. 1997) logic in strtod that
+ * avoids underflows on inputs whose result does not underflow.
+ */
+ #ifdef IS_LITTLE_ENDIAN
+ #define IEEE_8087
+ #else
+ #define IEEE_MC68k
+ #endif
+
+ #ifndef Long
+ #define Long int32
+ #endif
+
+ #ifndef ULong
+ #define ULong uint32
+ #endif
+
+ #define Bug(errorMessageString) JS_ASSERT(!errorMessageString)
+
+ #include "stdlib.h"
+ #include "string.h"
+
+ #ifdef MALLOC
+ extern void *MALLOC(size_t);
+ #else
+ #define MALLOC malloc
+ #endif
+
+ #define Omit_Private_Memory
+ /* Private memory currently doesn't work with JS_THREADSAFE */
+ #ifndef Omit_Private_Memory
+ #ifndef PRIVATE_MEM
+ #define PRIVATE_MEM 2000
+ #endif
+ #define PRIVATE_mem ((PRIVATE_MEM+sizeof(double)-1)/sizeof(double))
+ static double private_mem[PRIVATE_mem], *pmem_next = private_mem;
+ #endif
+
+ #ifdef Bad_float_h
+ #undef __STDC__
+
+ #define DBL_DIG 15
+ #define DBL_MAX_10_EXP 308
+ #define DBL_MAX_EXP 1024
+ #define FLT_RADIX 2
+ #define FLT_ROUNDS 1
+ #define DBL_MAX 1.7976931348623157e+308
+
+
+
+ #ifndef LONG_MAX
+ #define LONG_MAX 2147483647
+ #endif
+
+ #else /* ifndef Bad_float_h */
+ #include "float.h"
+ #endif /* Bad_float_h */
+
+ #ifndef __MATH_H__
+ #include "math.h"
+ #endif
+
+ #ifndef CONST
+ #define CONST const
+ #endif
+
+ #if defined(IEEE_8087) + defined(IEEE_MC68k) != 1
+ Exactly one of IEEE_8087 or IEEE_MC68k should be defined.
+ #endif
+
+ #define word0(x) JSDOUBLE_HI32(x)
+ #define set_word0(x, y) JSDOUBLE_SET_HI32(x, y)
+ #define word1(x) JSDOUBLE_LO32(x)
+ #define set_word1(x, y) JSDOUBLE_SET_LO32(x, y)
+
+ #define Storeinc(a,b,c) (*(a)++ = (b) << 16 | (c) & 0xffff)
+
+ /* #define P DBL_MANT_DIG */
+ /* Ten_pmax = floor(P*log(2)/log(5)) */
+ /* Bletch = (highest power of 2 < DBL_MAX_10_EXP) / 16 */
+ /* Quick_max = floor((P-1)*log(FLT_RADIX)/log(10) - 1) */
+ /* Int_max = floor(P*log(FLT_RADIX)/log(10) - 1) */
+
+ #define Exp_shift 20
+ #define Exp_shift1 20
+ #define Exp_msk1 0x100000
+ #define Exp_msk11 0x100000
+ #define Exp_mask 0x7ff00000
+ #define P 53
+ #define Bias 1023
+ #define Emin (-1022)
+ #define Exp_1 0x3ff00000
+ #define Exp_11 0x3ff00000
+ #define Ebits 11
+ #define Frac_mask 0xfffff
+ #define Frac_mask1 0xfffff
+ #define Ten_pmax 22
+ #define Bletch 0x10
+ #define Bndry_mask 0xfffff
+ #define Bndry_mask1 0xfffff
+ #define LSB 1
+ #define Sign_bit 0x80000000
+ #define Log2P 1
+ #define Tiny0 0
+ #define Tiny1 1
+ #define Quick_max 14
+ #define Int_max 14
+ #define Infinite(x) (word0(x) == 0x7ff00000) /* sufficient test for here */
+ #ifndef NO_IEEE_Scale
+ #define Avoid_Underflow
+ #endif
+
+
+
+ #ifdef RND_PRODQUOT
+ #define rounded_product(a,b) a = rnd_prod(a, b)
+ #define rounded_quotient(a,b) a = rnd_quot(a, b)
+ extern double rnd_prod(double, double), rnd_quot(double, double);
+ #else
+ #define rounded_product(a,b) a *= b
+ #define rounded_quotient(a,b) a /= b
+ #endif
+
+ #define Big0 (Frac_mask1 | Exp_msk1*(DBL_MAX_EXP+Bias-1))
+ #define Big1 0xffffffff
+
+ #ifndef JS_HAVE_LONG_LONG
+ #undef ULLong
+ #else /* long long available */
+ #ifndef Llong
+ #define Llong JSInt64
+ #endif
+ #ifndef ULLong
+ #define ULLong JSUint64
+ #endif
+ #endif /* JS_HAVE_LONG_LONG */
+
+ #ifdef JS_THREADSAFE
+ #define MULTIPLE_THREADS
+ static PRLock *freelist_lock;
+ #define ACQUIRE_DTOA_LOCK() \
+ JS_BEGIN_MACRO \
+ if (!initialized) \
+ InitDtoa(); \
+ PR_Lock(freelist_lock); \
+ JS_END_MACRO
+ #define RELEASE_DTOA_LOCK() PR_Unlock(freelist_lock)
+ #else
+ #undef MULTIPLE_THREADS
+ #define ACQUIRE_DTOA_LOCK() /*nothing*/
+ #define RELEASE_DTOA_LOCK() /*nothing*/
+ #endif
+
+ #define Kmax 15
+
+ struct Bigint {
+ struct Bigint *next; /* Free list link */
+ int32 k; /* lg2(maxwds) */
+ int32 maxwds; /* Number of words allocated for x */
+ int32 sign; /* Zero if positive, 1 if negative. Ignored by most Bigint routines! */
+ int32 wds; /* Actual number of words. If value is nonzero, the most significant word must be nonzero. */
+ ULong x[1]; /* wds words of number in little endian order */
+ };
+
+ #ifdef ENABLE_OOM_TESTING
+ /* Out-of-memory testing. Use a good testcase (over and over) and then use
+ * these routines to cause a memory failure on every possible Balloc allocation,
+ * to make sure that all out-of-memory paths can be followed. See bug 14044.
+ */
+
+ static int allocationNum; /* which allocation is next? */
+ static int desiredFailure; /* which allocation should fail? */
+
+ /**
+ * js_BigintTestingReset
+ *
+ * Call at the beginning of a test run to set the allocation failure position.
+ * (Set to 0 to just have the engine count allocations without failing.)
+ */
+ JS_PUBLIC_API(void)
+ js_BigintTestingReset(int newFailure)
+ {
+ allocationNum = 0;
+ desiredFailure = newFailure;
+ }
+
+ /**
+ * js_BigintTestingWhere
+ *
+ * Report the current allocation position. This is really only useful when you
+ * want to learn how many allocations a test run has.
+ */
+ JS_PUBLIC_API(int)
+ js_BigintTestingWhere()
+ {
+ return allocationNum;
+ }
+
+
+ /*
+ * So here's what you do: Set up a fantastic test case that exercises the
+ * elements of the code you wish. Set the failure point at 0 and run the test,
+ * then get the allocation position. This number is the number of allocations
+ * your test makes. Now loop from 1 to that number, setting the failure point
+ * at each loop count, and run the test over and over, causing failures at each
+ * step. Any memory failure *should* cause a Out-Of-Memory exception; if it
+ * doesn't, then there's still an error here.
+ */
+ #endif
+
+ typedef struct Bigint Bigint;
+
+ static Bigint *freelist[Kmax+1];
+
+ /*
+ * Allocate a Bigint with 2^k words.
+ * This is not threadsafe. The caller must use thread locks
+ */
+ static Bigint *Balloc(int32 k)
+ {
+ int32 x;
+ Bigint *rv;
+ #ifndef Omit_Private_Memory
+ uint32 len;
+ #endif
+
+ #ifdef ENABLE_OOM_TESTING
+ if (++allocationNum == desiredFailure) {
+ printf("Forced Failing Allocation number %d\n", allocationNum);
+ return NULL;
+ }
+ #endif
+
+ if ((rv = freelist[k]) != NULL)
+ freelist[k] = rv->next;
+ if (rv == NULL) {
+ x = 1 << k;
+ #ifdef Omit_Private_Memory
+ rv = (Bigint *)MALLOC(sizeof(Bigint) + (x-1)*sizeof(ULong));
+ #else
+ len = (sizeof(Bigint) + (x-1)*sizeof(ULong) + sizeof(double) - 1)
+ /sizeof(double);
+ if (pmem_next - private_mem + len <= PRIVATE_mem) {
+ rv = (Bigint*)pmem_next;
+ pmem_next += len;
+ }
+ else
+ rv = (Bigint*)MALLOC(len*sizeof(double));
+ #endif
+ if (!rv)
+ return NULL;
+ rv->k = k;
+ rv->maxwds = x;
+ }
+ rv->sign = rv->wds = 0;
+ return rv;
+ }
+
+ static void Bfree(Bigint *v)
+ {
+ if (v) {
+ v->next = freelist[v->k];
+ freelist[v->k] = v;
+ }
+ }
+
+ #define Bcopy(x,y) memcpy((char *)&x->sign, (char *)&y->sign, \
+ y->wds*sizeof(Long) + 2*sizeof(int32))
+
+ /* Return b*m + a. Deallocate the old b. Both a and m must be between 0 and
+ * 65535 inclusive. NOTE: old b is deallocated on memory failure.
+ */
+ static Bigint *multadd(Bigint *b, int32 m, int32 a)
+ {
+ int32 i, wds;
+ #ifdef ULLong
+ ULong *x;
+ ULLong carry, y;
+ #else
+ ULong carry, *x, y;
+ ULong xi, z;
+ #endif
+ Bigint *b1;
+
+ #ifdef ENABLE_OOM_TESTING
+ if (++allocationNum == desiredFailure) {
+ /* Faux allocation, because I'm not getting all of the failure paths
+ * without it.
+ */
+ printf("Forced Failing Allocation number %d\n", allocationNum);
+ Bfree(b);
+ return NULL;
+ }
+ #endif
+
+ wds = b->wds;
+ x = b->x;
+ i = 0;
+ carry = a;
+ do {
+ #ifdef ULLong
+ y = *x * (ULLong)m + carry;
+ carry = y >> 32;
+ *x++ = (ULong)(y & 0xffffffffUL);
+ #else
+ xi = *x;
+ y = (xi & 0xffff) * m + carry;
+ z = (xi >> 16) * m + (y >> 16);
+ carry = z >> 16;
+ *x++ = (z << 16) + (y & 0xffff);
+ #endif
+ }
+ while(++i < wds);
+ if (carry) {
+ if (wds >= b->maxwds) {
+ b1 = Balloc(b->k+1);
+ if (!b1) {
+ Bfree(b);
+ return NULL;
+ }
+ Bcopy(b1, b);
+ Bfree(b);
+ b = b1;
+ }
+ b->x[wds++] = (ULong)carry;
+ b->wds = wds;
+ }
+ return b;
+ }
+
+ static Bigint *s2b(CONST char *s, int32 nd0, int32 nd, ULong y9)
+ {
+ Bigint *b;
+ int32 i, k;
+ Long x, y;
+
+ x = (nd + 8) / 9;
+ for(k = 0, y = 1; x > y; y <<= 1, k++) ;
+ b = Balloc(k);
+ if (!b)
+ return NULL;
+ b->x[0] = y9;
+ b->wds = 1;
+
+ i = 9;
+ if (9 < nd0) {
+ s += 9;
+ do {
+ b = multadd(b, 10, *s++ - '0');
+ if (!b)
+ return NULL;
+ } while(++i < nd0);
+ s++;
+ }
+ else
+ s += 10;
+ for(; i < nd; i++) {
+ b = multadd(b, 10, *s++ - '0');
+ if (!b)
+ return NULL;
+ }
+ return b;
+ }
+
+
+ /* Return the number (0 through 32) of most significant zero bits in x. */
+ static int32 hi0bits(register ULong x)
+ {
+ register int32 k = 0;
+
+ if (!(x & 0xffff0000)) {
+ k = 16;
+ x <<= 16;
+ }
+ if (!(x & 0xff000000)) {
+ k += 8;
+ x <<= 8;
+ }
+ if (!(x & 0xf0000000)) {
+ k += 4;
+ x <<= 4;
+ }
+ if (!(x & 0xc0000000)) {
+ k += 2;
+ x <<= 2;
+ }
+ if (!(x & 0x80000000)) {
+ k++;
+ if (!(x & 0x40000000))
+ return 32;
+ }
+ return k;
+ }
+
+
+ /* Return the number (0 through 32) of least significant zero bits in y.
+ * Also shift y to the right past these 0 through 32 zeros so that y's
+ * least significant bit will be set unless y was originally zero. */
+ static int32 lo0bits(ULong *y)
+ {
+ register int32 k;
+ register ULong x = *y;
+
+ if (x & 7) {
+ if (x & 1)
+ return 0;
+ if (x & 2) {
+ *y = x >> 1;
+ return 1;
+ }
+ *y = x >> 2;
+ return 2;
+ }
+ k = 0;
+ if (!(x & 0xffff)) {
+ k = 16;
+ x >>= 16;
+ }
+ if (!(x & 0xff)) {
+ k += 8;
+ x >>= 8;
+ }
+ if (!(x & 0xf)) {
+ k += 4;
+ x >>= 4;
+ }
+ if (!(x & 0x3)) {
+ k += 2;
+ x >>= 2;
+ }
+ if (!(x & 1)) {
+ k++;
+ x >>= 1;
+ if (!x & 1)
+ return 32;
+ }
+ *y = x;
+ return k;
+ }
+
+ /* Return a new Bigint with the given integer value, which must be nonnegative. */
+ static Bigint *i2b(int32 i)
+ {
+ Bigint *b;
+
+ b = Balloc(1);
+ if (!b)
+ return NULL;
+ b->x[0] = i;
+ b->wds = 1;
+ return b;
+ }
+
+ /* Return a newly allocated product of a and b. */
+ static Bigint *mult(CONST Bigint *a, CONST Bigint *b)
+ {
+ CONST Bigint *t;
+ Bigint *c;
+ int32 k, wa, wb, wc;
+ ULong y;
+ ULong *xc, *xc0, *xce;
+ CONST ULong *x, *xa, *xae, *xb, *xbe;
+ #ifdef ULLong
+ ULLong carry, z;
+ #else
+ ULong carry, z;
+ ULong z2;
+ #endif
+
+ if (a->wds < b->wds) {
+ t = a;
+ a = b;
+ b = t;
+ }
+ k = a->k;
+ wa = a->wds;
+ wb = b->wds;
+ wc = wa + wb;
+ if (wc > a->maxwds)
+ k++;
+ c = Balloc(k);
+ if (!c)
+ return NULL;
+ for(xc = c->x, xce = xc + wc; xc < xce; xc++)
+ *xc = 0;
+ xa = a->x;
+ xae = xa + wa;
+ xb = b->x;
+ xbe = xb + wb;
+ xc0 = c->x;
+ #ifdef ULLong
+ for(; xb < xbe; xc0++) {
+ if ((y = *xb++) != 0) {
+ x = xa;
+ xc = xc0;
+ carry = 0;
+ do {
+ z = *x++ * (ULLong)y + *xc + carry;
+ carry = z >> 32;
+ *xc++ = (ULong)(z & 0xffffffffUL);
+ }
+ while(x < xae);
+ *xc = (ULong)carry;
+ }
+ }
+ #else
+ for(; xb < xbe; xb++, xc0++) {
+ if ((y = *xb & 0xffff) != 0) {
+ x = xa;
+ xc = xc0;
+ carry = 0;
+ do {
+ z = (*x & 0xffff) * y + (*xc & 0xffff) + carry;
+ carry = z >> 16;
+ z2 = (*x++ >> 16) * y + (*xc >> 16) + carry;
+ carry = z2 >> 16;
+ Storeinc(xc, z2, z);
+ }
+ while(x < xae);
+ *xc = carry;
+ }
+ if ((y = *xb >> 16) != 0) {
+ x = xa;
+ xc = xc0;
+ carry = 0;
+ z2 = *xc;
+ do {
+ z = (*x & 0xffff) * y + (*xc >> 16) + carry;
+ carry = z >> 16;
+ Storeinc(xc, z, z2);
+ z2 = (*x++ >> 16) * y + (*xc & 0xffff) + carry;
+ carry = z2 >> 16;
+ }
+ while(x < xae);
+ *xc = z2;
+ }
+ }
+ #endif
+ for(xc0 = c->x, xc = xc0 + wc; wc > 0 && !*--xc; --wc) ;
+ c->wds = wc;
+ return c;
+ }
+
+ /*
+ * 'p5s' points to a linked list of Bigints that are powers of 5.
+ * This list grows on demand, and it can only grow: it won't change
+ * in any other way. So if we read 'p5s' or the 'next' field of
+ * some Bigint on the list, and it is not NULL, we know it won't
+ * change to NULL or some other value. Only when the value of
+ * 'p5s' or 'next' is NULL do we need to acquire the lock and add
+ * a new Bigint to the list.
+ */
+
+ static Bigint *p5s;
+
+ #ifdef JS_THREADSAFE
+ static PRLock *p5s_lock;
+ #endif
+
+ /* Return b * 5^k. Deallocate the old b. k must be nonnegative. */
+ /* NOTE: old b is deallocated on memory failure. */
+ static Bigint *pow5mult(Bigint *b, int32 k)
+ {
+ Bigint *b1, *p5, *p51;
+ int32 i;
+ static CONST int32 p05[3] = { 5, 25, 125 };
+
+ if ((i = k & 3) != 0) {
+ b = multadd(b, p05[i-1], 0);
+ if (!b)
+ return NULL;
+ }
+
+ if (!(k >>= 2))
+ return b;
+ if (!(p5 = p5s)) {
+ #ifdef JS_THREADSAFE
+ /*
+ * We take great care to not call i2b() and Bfree()
+ * while holding the lock.
+ */
+ Bigint *wasted_effort = NULL;
+ p5 = i2b(625);
+ if (!p5) {
+ Bfree(b);
+ return NULL;
+ }
+ /* lock and check again */
+ PR_Lock(p5s_lock);
+ if (!p5s) {
+ /* first time */
+ p5s = p5;
+ p5->next = 0;
+ } else {
+ /* some other thread just beat us */
+ wasted_effort = p5;
+ p5 = p5s;
+ }
+ PR_Unlock(p5s_lock);
+ if (wasted_effort) {
+ Bfree(wasted_effort);
+ }
+ #else
+ /* first time */
+ p5 = p5s = i2b(625);
+ if (!p5) {
+ Bfree(b);
+ return NULL;
+ }
+ p5->next = 0;
+ #endif
+ }
+ for(;;) {
+ if (k & 1) {
+ b1 = mult(b, p5);
+ Bfree(b);
+ if (!b1)
+ return NULL;
+ b = b1;
+ }
+ if (!(k >>= 1))
+ break;
+ if (!(p51 = p5->next)) {
+ #ifdef JS_THREADSAFE
+ Bigint *wasted_effort = NULL;
+ p51 = mult(p5, p5);
+ if (!p51) {
+ Bfree(b);
+ return NULL;
+ }
+ PR_Lock(p5s_lock);
+ if (!p5->next) {
+ p5->next = p51;
+ p51->next = 0;
+ } else {
+ wasted_effort = p51;
+ p51 = p5->next;
+ }
+ PR_Unlock(p5s_lock);
+ if (wasted_effort) {
+ Bfree(wasted_effort);
+ }
+ #else
+ p51 = mult(p5,p5);
+ if (!p51) {
+ Bfree(b);
+ return NULL;
+ }
+ p51->next = 0;
+ p5->next = p51;
+ #endif
+ }
+ p5 = p51;
+ }
+ return b;
+ }
+
+ /* Return b * 2^k. Deallocate the old b. k must be nonnegative.
+ * NOTE: on memory failure, old b is deallocated. */
+ static Bigint *lshift(Bigint *b, int32 k)
+ {
+ int32 i, k1, n, n1;
+ Bigint *b1;
+ ULong *x, *x1, *xe, z;
+
+ n = k >> 5;
+ k1 = b->k;
+ n1 = n + b->wds + 1;
+ for(i = b->maxwds; n1 > i; i <<= 1)
+ k1++;
+ b1 = Balloc(k1);
+ if (!b1)
+ goto done;
+ x1 = b1->x;
+ for(i = 0; i < n; i++)
+ *x1++ = 0;
+ x = b->x;
+ xe = x + b->wds;
+ if (k &= 0x1f) {
+ k1 = 32 - k;
+ z = 0;
+ do {
+ *x1++ = *x << k | z;
+ z = *x++ >> k1;
+ }
+ while(x < xe);
+ if ((*x1 = z) != 0)
+ ++n1;
+ }
+ else do
+ *x1++ = *x++;
+ while(x < xe);
+ b1->wds = n1 - 1;
+ done:
+ Bfree(b);
+ return b1;
+ }
+
+ /* Return -1, 0, or 1 depending on whether a<b, a==b, or a>b, respectively. */
+ static int32 cmp(Bigint *a, Bigint *b)
+ {
+ ULong *xa, *xa0, *xb, *xb0;
+ int32 i, j;
+
+ i = a->wds;
+ j = b->wds;
+ #ifdef DEBUG
+ if (i > 1 && !a->x[i-1])
+ Bug("cmp called with a->x[a->wds-1] == 0");
+ if (j > 1 && !b->x[j-1])
+ Bug("cmp called with b->x[b->wds-1] == 0");
+ #endif
+ if (i -= j)
+ return i;
+ xa0 = a->x;
+ xa = xa0 + j;
+ xb0 = b->x;
+ xb = xb0 + j;
+ for(;;) {
+ if (*--xa != *--xb)
+ return *xa < *xb ? -1 : 1;
+ if (xa <= xa0)
+ break;
+ }
+ return 0;
+ }
+
+ static Bigint *diff(Bigint *a, Bigint *b)
+ {
+ Bigint *c;
+ int32 i, wa, wb;
+ ULong *xa, *xae, *xb, *xbe, *xc;
+ #ifdef ULLong
+ ULLong borrow, y;
+ #else
+ ULong borrow, y;
+ ULong z;
+ #endif
+
+ i = cmp(a,b);
+ if (!i) {
+ c = Balloc(0);
+ if (!c)
+ return NULL;
+ c->wds = 1;
+ c->x[0] = 0;
+ return c;
+ }
+ if (i < 0) {
+ c = a;
+ a = b;
+ b = c;
+ i = 1;
+ }
+ else
+ i = 0;
+ c = Balloc(a->k);
+ if (!c)
+ return NULL;
+ c->sign = i;
+ wa = a->wds;
+ xa = a->x;
+ xae = xa + wa;
+ wb = b->wds;
+ xb = b->x;
+ xbe = xb + wb;
+ xc = c->x;
+ borrow = 0;
+ #ifdef ULLong
+ do {
+ y = (ULLong)*xa++ - *xb++ - borrow;
+ borrow = y >> 32 & 1UL;
+ *xc++ = (ULong)(y & 0xffffffffUL);
+ }
+ while(xb < xbe);
+ while(xa < xae) {
+ y = *xa++ - borrow;
+ borrow = y >> 32 & 1UL;
+ *xc++ = (ULong)(y & 0xffffffffUL);
+ }
+ #else
+ do {
+ y = (*xa & 0xffff) - (*xb & 0xffff) - borrow;
+ borrow = (y & 0x10000) >> 16;
+ z = (*xa++ >> 16) - (*xb++ >> 16) - borrow;
+ borrow = (z & 0x10000) >> 16;
+ Storeinc(xc, z, y);
+ }
+ while(xb < xbe);
+ while(xa < xae) {
+ y = (*xa & 0xffff) - borrow;
+ borrow = (y & 0x10000) >> 16;
+ z = (*xa++ >> 16) - borrow;
+ borrow = (z & 0x10000) >> 16;
+ Storeinc(xc, z, y);
+ }
+ #endif
+ while(!*--xc)
+ wa--;
+ c->wds = wa;
+ return c;
+ }
+
+ /* Return the absolute difference between x and the adjacent greater-magnitude double number (ignoring exponent overflows). */
+ static double ulp(double x)
+ {
+ register Long L;
+ double a = 0;
+
+ L = (word0(x) & Exp_mask) - (P-1)*Exp_msk1;
+ #ifndef Sudden_Underflow
+ if (L > 0) {
+ #endif
+ set_word0(a, L);
+ set_word1(a, 0);
+ #ifndef Sudden_Underflow
+ }
+ else {
+ L = -L >> Exp_shift;
+ if (L < Exp_shift) {
+ set_word0(a, 0x80000 >> L);
+ set_word1(a, 0);
+ }
+ else {
+ set_word0(a, 0);
+ L -= Exp_shift;
+ set_word1(a, L >= 31 ? 1 : 1 << (31 - L));
+ }
+ }
+ #endif
+ return a;
+ }
+
+
+ static double b2d(Bigint *a, int32 *e)
+ {
+ ULong *xa, *xa0, w, y, z;
+ int32 k;
+ double d = 0;
+ #define d0 word0(d)
+ #define d1 word1(d)
+ #define set_d0(x) set_word0(d, x)
+ #define set_d1(x) set_word1(d, x)
+
+ xa0 = a->x;
+ xa = xa0 + a->wds;
+ y = *--xa;
+ #ifdef DEBUG
+ if (!y) Bug("zero y in b2d");
+ #endif
+ k = hi0bits(y);
+ *e = 32 - k;
+ if (k < Ebits) {
+ set_d0(Exp_1 | y >> (Ebits - k));
+ w = xa > xa0 ? *--xa : 0;
+ set_d1(y << (32-Ebits + k) | w >> (Ebits - k));
+ goto ret_d;
+ }
+ z = xa > xa0 ? *--xa : 0;
+ if (k -= Ebits) {
+ set_d0(Exp_1 | y << k | z >> (32 - k));
+ y = xa > xa0 ? *--xa : 0;
+ set_d1(z << k | y >> (32 - k));
+ }
+ else {
+ set_d0(Exp_1 | y);
+ set_d1(z);
+ }
+ ret_d:
+ #undef d0
+ #undef d1
+ #undef set_d0
+ #undef set_d1
+ return d;
+ }
+
+
+ /* Convert d into the form b*2^e, where b is an odd integer. b is the returned
+ * Bigint and e is the returned binary exponent. Return the number of significant
+ * bits in b in bits. d must be finite and nonzero. */
+ static Bigint *d2b(double d, int32 *e, int32 *bits)
+ {
+ Bigint *b;
+ int32 de, i, k;
+ ULong *x, y, z;
+ #define d0 word0(d)
+ #define d1 word1(d)
+ #define set_d0(x) set_word0(d, x)
+ #define set_d1(x) set_word1(d, x)
+
+ b = Balloc(1);
+ if (!b)
+ return NULL;
+ x = b->x;
+
+ z = d0 & Frac_mask;
+ set_d0(d0 & 0x7fffffff); /* clear sign bit, which we ignore */
+ #ifdef Sudden_Underflow
+ de = (int32)(d0 >> Exp_shift);
+ z |= Exp_msk11;
+ #else
+ if ((de = (int32)(d0 >> Exp_shift)) != 0)
+ z |= Exp_msk1;
+ #endif
+ if ((y = d1) != 0) {
+ if ((k = lo0bits(&y)) != 0) {
+ x[0] = y | z << (32 - k);
+ z >>= k;
+ }
+ else
+ x[0] = y;
+ i = b->wds = (x[1] = z) ? 2 : 1;
+ }
+ else {
+ JS_ASSERT(z);
+ k = lo0bits(&z);
+ x[0] = z;
+ i = b->wds = 1;
+ k += 32;
+ }
+ #ifndef Sudden_Underflow
+ if (de) {
+ #endif
+ *e = de - Bias - (P-1) + k;
+ *bits = P - k;
+ #ifndef Sudden_Underflow
+ }
+ else {
+ *e = de - Bias - (P-1) + 1 + k;
+ *bits = 32*i - hi0bits(x[i-1]);
+ }
+ #endif
+ return b;
+ }
+ #undef d0
+ #undef d1
+ #undef set_d0
+ #undef set_d1
+
+
+ static double ratio(Bigint *a, Bigint *b)
+ {
+ double da, db;
+ int32 k, ka, kb;
+
+ da = b2d(a, &ka);
+ db = b2d(b, &kb);
+ k = ka - kb + 32*(a->wds - b->wds);
+ if (k > 0)
+ set_word0(da, word0(da) + k*Exp_msk1);
+ else {
+ k = -k;
+ set_word0(db, word0(db) + k*Exp_msk1);
+ }
+ return da / db;
+ }
+
+ static CONST double
+ tens[] = {
+ 1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
+ 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+ 1e20, 1e21, 1e22
+ };
+
+ static CONST double bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };
+ static CONST double tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128,
+ #ifdef Avoid_Underflow
+ 9007199254740992.e-256
+ #else
+ 1e-256
+ #endif
+ };
+ /* The factor of 2^53 in tinytens[4] helps us avoid setting the underflow */
+ /* flag unnecessarily. It leads to a song and dance at the end of strtod. */
+ #define Scale_Bit 0x10
+ #define n_bigtens 5
+
+
+ #ifdef INFNAN_CHECK
+
+ #ifndef NAN_WORD0
+ #define NAN_WORD0 0x7ff80000
+ #endif
+
+ #ifndef NAN_WORD1
+ #define NAN_WORD1 0
+ #endif
+
+ static int match(CONST char **sp, char *t)
+ {
+ int c, d;
+ CONST char *s = *sp;
+
+ while(d = *t++) {
+ if ((c = *++s) >= 'A' && c <= 'Z')
+ c += 'a' - 'A';
+ if (c != d)
+ return 0;
+ }
+ *sp = s + 1;
+ return 1;
+ }
+ #endif /* INFNAN_CHECK */
+
+
+ #ifdef JS_THREADSAFE
+ static JSBool initialized = JS_FALSE;
+
+ /* hacked replica of nspr _PR_InitDtoa */
+ static void InitDtoa(void)
+ {
+ freelist_lock = PR_NewLock();
+ p5s_lock = PR_NewLock();
+ initialized = JS_TRUE;
+ }
+ #endif
+
+ void js_FinishDtoa(void)
+ {
+ int count;
+ Bigint *temp;
+
+ #ifdef JS_THREADSAFE
+ if (initialized == JS_TRUE) {
+ PR_DestroyLock(freelist_lock);
+ PR_DestroyLock(p5s_lock);
+ initialized = JS_FALSE;
+ }
+ #endif
+
+ /* clear down the freelist array and p5s */
+
+ /* static Bigint *freelist[Kmax+1]; */
+ for (count = 0; count <= Kmax; count++) {
+ Bigint **listp = &freelist[count];
+ while ((temp = *listp) != NULL) {
+ *listp = temp->next;
+ free(temp);
+ }
+ freelist[count] = NULL;
+ }
+
+ /* static Bigint *p5s; */
+ while (p5s) {
+ temp = p5s;
+ p5s = p5s->next;
+ free(temp);
+ }
+ }
+
+ /* nspr2 watcom bug ifdef omitted */
+
+ JS_FRIEND_API(double)
+ JS_strtod(CONST char *s00, char **se, int *err)
+ {
+ int32 scale;
+ int32 bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, dsign,
+ e, e1, esign, i, j, k, nd, nd0, nf, nz, nz0, sign;
+ CONST char *s, *s0, *s1;
+ double aadj, aadj1, adj, rv, rv0;
+ Long L;
+ ULong y, z;
+ Bigint *bb, *bb1, *bd, *bd0, *bs, *delta;
+
+ *err = 0;
+
+ bb = bd = bs = delta = NULL;
+ sign = nz0 = nz = 0;
+ rv = 0.;
+
+ /* Locking for Balloc's shared buffers that will be used in this block */
+ ACQUIRE_DTOA_LOCK();
+
+ for(s = s00;;s++) switch(*s) {
+ case '-':
+ sign = 1;
+ /* no break */
+ case '+':
+ if (*++s)
+ goto break2;
+ /* no break */
+ case 0:
+ s = s00;
+ goto ret;
+ case '\t':
+ case '\n':
+ case '\v':
+ case '\f':
+ case '\r':
+ case ' ':
+ continue;
+ default:
+ goto break2;
+ }
+ break2:
+
+ if (*s == '0') {
+ nz0 = 1;
+ while(*++s == '0') ;
+ if (!*s)
+ goto ret;
+ }
+ s0 = s;
+ y = z = 0;
+ for(nd = nf = 0; (c = *s) >= '0' && c <= '9'; nd++, s++)
+ if (nd < 9)
+ y = 10*y + c - '0';
+ else if (nd < 16)
+ z = 10*z + c - '0';
+ nd0 = nd;
+ if (c == '.') {
+ c = *++s;
+ if (!nd) {
+ for(; c == '0'; c = *++s)
+ nz++;
+ if (c > '0' && c <= '9') {
+ s0 = s;
+ nf += nz;
+ nz = 0;
+ goto have_dig;
+ }
+ goto dig_done;
+ }
+ for(; c >= '0' && c <= '9'; c = *++s) {
+ have_dig:
+ nz++;
+ if (c -= '0') {
+ nf += nz;
+ for(i = 1; i < nz; i++)
+ if (nd++ < 9)
+ y *= 10;
+ else if (nd <= DBL_DIG + 1)
+ z *= 10;
+ if (nd++ < 9)
+ y = 10*y + c;
+ else if (nd <= DBL_DIG + 1)
+ z = 10*z + c;
+ nz = 0;
+ }
+ }
+ }
+ dig_done:
+ e = 0;
+ if (c == 'e' || c == 'E') {
+ if (!nd && !nz && !nz0) {
+ s = s00;
+ goto ret;
+ }
+ s00 = s;
+ esign = 0;
+ switch(c = *++s) {
+ case '-':
+ esign = 1;
+ case '+':
+ c = *++s;
+ }
+ if (c >= '0' && c <= '9') {
+ while(c == '0')
+ c = *++s;
+ if (c > '0' && c <= '9') {
+ L = c - '0';
+ s1 = s;
+ while((c = *++s) >= '0' && c <= '9')
+ L = 10*L + c - '0';
+ if (s - s1 > 8 || L > 19999)
+ /* Avoid confusion from exponents
+ * so large that e might overflow.
+ */
+ e = 19999; /* safe for 16 bit ints */
+ else
+ e = (int32)L;
+ if (esign)
+ e = -e;
+ }
+ else
+ e = 0;
+ }
+ else
+ s = s00;
+ }
+ if (!nd) {
+ if (!nz && !nz0) {
+ #ifdef INFNAN_CHECK
+ /* Check for Nan and Infinity */
+ switch(c) {
+ case 'i':
+ case 'I':
+ if (match(&s,"nfinity")) {
+ word0(rv) = 0x7ff00000;
+ word1(rv) = 0;
+ goto ret;
+ }
+ break;
+ case 'n':
+ case 'N':
+ if (match(&s, "an")) {
+ word0(rv) = NAN_WORD0;
+ word1(rv) = NAN_WORD1;
+ goto ret;
+ }
+ }
+ #endif /* INFNAN_CHECK */
+ s = s00;
+ }
+ goto ret;
+ }
+ e1 = e -= nf;
+
+ /* Now we have nd0 digits, starting at s0, followed by a
+ * decimal point, followed by nd-nd0 digits. The number we're
+ * after is the integer represented by those digits times
+ * 10**e */
+
+ if (!nd0)
+ nd0 = nd;
+ k = nd < DBL_DIG + 1 ? nd : DBL_DIG + 1;
+ rv = y;
+ if (k > 9)
+ rv = tens[k - 9] * rv + z;
+ bd0 = 0;
+ if (nd <= DBL_DIG
+ #ifndef RND_PRODQUOT
+ && FLT_ROUNDS == 1
+ #endif
+ ) {
+ if (!e)
+ goto ret;
+ if (e > 0) {
+ if (e <= Ten_pmax) {
+ /* rv = */ rounded_product(rv, tens[e]);
+ goto ret;
+ }
+ i = DBL_DIG - nd;
+ if (e <= Ten_pmax + i) {
+ /* A fancier test would sometimes let us do
+ * this for larger i values.
+ */
+ e -= i;
+ rv *= tens[i];
+ /* rv = */ rounded_product(rv, tens[e]);
+ goto ret;
+ }
+ }
+ #ifndef Inaccurate_Divide
+ else if (e >= -Ten_pmax) {
+ /* rv = */ rounded_quotient(rv, tens[-e]);
+ goto ret;
+ }
+ #endif
+ }
+ e1 += nd - k;
+
+ scale = 0;
+
+ /* Get starting approximation = rv * 10**e1 */
+
+ if (e1 > 0) {
+ if ((i = e1 & 15) != 0)
+ rv *= tens[i];
+ if (e1 &= ~15) {
+ if (e1 > DBL_MAX_10_EXP) {
+ ovfl:
+ *err = JS_DTOA_ERANGE;
+ #ifdef __STDC__
+ rv = HUGE_VAL;
+ #else
+ /* Can't trust HUGE_VAL */
+ word0(rv) = Exp_mask;
+ word1(rv) = 0;
+ #endif
+ if (bd0)
+ goto retfree;
+ goto ret;
+ }
+ e1 >>= 4;
+ for(j = 0; e1 > 1; j++, e1 >>= 1)
+ if (e1 & 1)
+ rv *= bigtens[j];
+ /* The last multiplication could overflow. */
+ set_word0(rv, word0(rv) - P*Exp_msk1);
+ rv *= bigtens[j];
+ if ((z = word0(rv) & Exp_mask) > Exp_msk1*(DBL_MAX_EXP+Bias-P))
+ goto ovfl;
+ if (z > Exp_msk1*(DBL_MAX_EXP+Bias-1-P)) {
+ /* set to largest number */
+ /* (Can't trust DBL_MAX) */
+ set_word0(rv, Big0);
+ set_word1(rv, Big1);
+ }
+ else
+ set_word0(rv, word0(rv) + P*Exp_msk1);
+ }
+ }
+ else if (e1 < 0) {
+ e1 = -e1;
+ if ((i = e1 & 15) != 0)
+ rv /= tens[i];
+ if (e1 &= ~15) {
+ e1 >>= 4;
+ if (e1 >= 1 << n_bigtens)
+ goto undfl;
+ #ifdef Avoid_Underflow
+ if (e1 & Scale_Bit)
+ scale = P;
+ for(j = 0; e1 > 0; j++, e1 >>= 1)
+ if (e1 & 1)
+ rv *= tinytens[j];
+ if (scale && (j = P + 1 - ((word0(rv) & Exp_mask)
+ >> Exp_shift)) > 0) {
+ /* scaled rv is denormal; zap j low bits */
+ if (j >= 32) {
+ set_word1(rv, 0);
+ set_word0(rv, word0(rv) & (0xffffffff << (j-32)));
+ if (!word0(rv))
+ set_word0(rv, 1);
+ }
+ else
+ set_word1(rv, word1(rv) & (0xffffffff << j));
+ }
+ #else
+ for(j = 0; e1 > 1; j++, e1 >>= 1)
+ if (e1 & 1)
+ rv *= tinytens[j];
+ /* The last multiplication could underflow. */
+ rv0 = rv;
+ rv *= tinytens[j];
+ if (!rv) {
+ rv = 2.*rv0;
+ rv *= tinytens[j];
+ #endif
+ if (!rv) {
+ undfl:
+ rv = 0.;
+ *err = JS_DTOA_ERANGE;
+ if (bd0)
+ goto retfree;
+ goto ret;
+ }
+ #ifndef Avoid_Underflow
+ set_word0(rv, Tiny0);
+ set_word1(rv, Tiny1);
+ /* The refinement below will clean
+ * this approximation up.
+ */
+ }
+ #endif
+ }
+ }
+
+ /* Now the hard part -- adjusting rv to the correct value.*/
+
+ /* Put digits into bd: true value = bd * 10^e */
+
+ bd0 = s2b(s0, nd0, nd, y);
+ if (!bd0)
+ goto nomem;
+
+ for(;;) {
+ bd = Balloc(bd0->k);
+ if (!bd)
+ goto nomem;
+ Bcopy(bd, bd0);
+ bb = d2b(rv, &bbe, &bbbits); /* rv = bb * 2^bbe */
+ if (!bb)
+ goto nomem;
+ bs = i2b(1);
+ if (!bs)
+ goto nomem;
+
+ if (e >= 0) {
+ bb2 = bb5 = 0;
+ bd2 = bd5 = e;
+ }
+ else {
+ bb2 = bb5 = -e;
+ bd2 = bd5 = 0;
+ }
+ if (bbe >= 0)
+ bb2 += bbe;
+ else
+ bd2 -= bbe;
+ bs2 = bb2;
+ #ifdef Sudden_Underflow
+ j = P + 1 - bbbits;
+ #else
+ #ifdef Avoid_Underflow
+ j = bbe - scale;
+ #else
+ j = bbe;
+ #endif
+ i = j + bbbits - 1; /* logb(rv) */
+ if (i < Emin) /* denormal */
+ j += P - Emin;
+ else
+ j = P + 1 - bbbits;
+ #endif
+ bb2 += j;
+ bd2 += j;
+ #ifdef Avoid_Underflow
+ bd2 += scale;
+ #endif
+ i = bb2 < bd2 ? bb2 : bd2;
+ if (i > bs2)
+ i = bs2;
+ if (i > 0) {
+ bb2 -= i;
+ bd2 -= i;
+ bs2 -= i;
+ }
+ if (bb5 > 0) {
+ bs = pow5mult(bs, bb5);
+ if (!bs)
+ goto nomem;
+ bb1 = mult(bs, bb);
+ if (!bb1)
+ goto nomem;
+ Bfree(bb);
+ bb = bb1;
+ }
+ if (bb2 > 0) {
+ bb = lshift(bb, bb2);
+ if (!bb)
+ goto nomem;
+ }
+ if (bd5 > 0) {
+ bd = pow5mult(bd, bd5);
+ if (!bd)
+ goto nomem;
+ }
+ if (bd2 > 0) {
+ bd = lshift(bd, bd2);
+ if (!bd)
+ goto nomem;
+ }
+ if (bs2 > 0) {
+ bs = lshift(bs, bs2);
+ if (!bs)
+ goto nomem;
+ }
+ delta = diff(bb, bd);
+ if (!delta)
+ goto nomem;
+ dsign = delta->sign;
+ delta->sign = 0;
+ i = cmp(delta, bs);
+ if (i < 0) {
+ /* Error is less than half an ulp -- check for
+ * special case of mantissa a power of two.
+ */
+ if (dsign || word1(rv) || word0(rv) & Bndry_mask
+ #ifdef Avoid_Underflow
+ || (word0(rv) & Exp_mask) <= Exp_msk1 + P*Exp_msk1
+ #else
+ || (word0(rv) & Exp_mask) <= Exp_msk1
+ #endif
+ ) {
+ #ifdef Avoid_Underflow
+ if (!delta->x[0] && delta->wds == 1)
+ dsign = 2;
+ #endif
+ break;
+ }
+ delta = lshift(delta,Log2P);
+ if (!delta)
+ goto nomem;
+ if (cmp(delta, bs) > 0)
+ goto drop_down;
+ break;
+ }
+ if (i == 0) {
+ /* exactly half-way between */
+ if (dsign) {
+ if ((word0(rv) & Bndry_mask1) == Bndry_mask1
+ && word1(rv) == 0xffffffff) {
+ /*boundary case -- increment exponent*/
+ set_word0(rv, (word0(rv) & Exp_mask) + Exp_msk1);
+ set_word1(rv, 0);
+ #ifdef Avoid_Underflow
+ dsign = 0;
+ #endif
+ break;
+ }
+ }
+ else if (!(word0(rv) & Bndry_mask) && !word1(rv)) {
+ #ifdef Avoid_Underflow
+ dsign = 2;
+ #endif
+ drop_down:
+ /* boundary case -- decrement exponent */
+ #ifdef Sudden_Underflow
+ L = word0(rv) & Exp_mask;
+ if (L <= Exp_msk1)
+ goto undfl;
+ L -= Exp_msk1;
+ #else
+ L = (word0(rv) & Exp_mask) - Exp_msk1;
+ #endif
+ set_word0(rv, L | Bndry_mask1);
+ set_word1(rv, 0xffffffff);
+ break;
+ }
+ #ifndef ROUND_BIASED
+ if (!(word1(rv) & LSB))
+ break;
+ #endif
+ if (dsign)
+ rv += ulp(rv);
+ #ifndef ROUND_BIASED
+ else {
+ rv -= ulp(rv);
+ #ifndef Sudden_Underflow
+ if (!rv)
+ goto undfl;
+ #endif
+ }
+ #ifdef Avoid_Underflow
+ dsign = 1 - dsign;
+ #endif
+ #endif
+ break;
+ }
+ if ((aadj = ratio(delta, bs)) <= 2.) {
+ if (dsign)
+ aadj = aadj1 = 1.;
+ else if (word1(rv) || word0(rv) & Bndry_mask) {
+ #ifndef Sudden_Underflow
+ if (word1(rv) == Tiny1 && !word0(rv))
+ goto undfl;
+ #endif
+ aadj = 1.;
+ aadj1 = -1.;
+ }
+ else {
+ /* special case -- power of FLT_RADIX to be */
+ /* rounded down... */
+
+ if (aadj < 2./FLT_RADIX)
+ aadj = 1./FLT_RADIX;
+ else
+ aadj *= 0.5;
+ aadj1 = -aadj;
+ }
+ }
+ else {
+ aadj *= 0.5;
+ aadj1 = dsign ? aadj : -aadj;
+ #ifdef Check_FLT_ROUNDS
+ switch(FLT_ROUNDS) {
+ case 2: /* towards +infinity */
+ aadj1 -= 0.5;
+ break;
+ case 0: /* towards 0 */
+ case 3: /* towards -infinity */
+ aadj1 += 0.5;
+ }
+ #else
+ if (FLT_ROUNDS == 0)
+ aadj1 += 0.5;
+ #endif
+ }
+ y = word0(rv) & Exp_mask;
+
+ /* Check for overflow */
+
+ if (y == Exp_msk1*(DBL_MAX_EXP+Bias-1)) {
+ rv0 = rv;
+ set_word0(rv, word0(rv) - P*Exp_msk1);
+ adj = aadj1 * ulp(rv);
+ rv += adj;
+ if ((word0(rv) & Exp_mask) >=
+ Exp_msk1*(DBL_MAX_EXP+Bias-P)) {
+ if (word0(rv0) == Big0 && word1(rv0) == Big1)
+ goto ovfl;
+ set_word0(rv, Big0);
+ set_word1(rv, Big1);
+ goto cont;
+ }
+ else
+ set_word0(rv, word0(rv) + P*Exp_msk1);
+ }
+ else {
+ #ifdef Sudden_Underflow
+ if ((word0(rv) & Exp_mask) <= P*Exp_msk1) {
+ rv0 = rv;
+ set_word0(rv, word0(rv) + P*Exp_msk1);
+ adj = aadj1 * ulp(rv);
+ rv += adj;
+ if ((word0(rv) & Exp_mask) <= P*Exp_msk1)
+ {
+ if (word0(rv0) == Tiny0
+ && word1(rv0) == Tiny1)
+ goto undfl;
+ set_word0(rv, Tiny0);
+ set_word1(rv, Tiny1);
+ goto cont;
+ }
+ else
+ set_word0(rv, word0(rv) - P*Exp_msk1);
+ }
+ else {
+ adj = aadj1 * ulp(rv);
+ rv += adj;
+ }
+ #else
+ /* Compute adj so that the IEEE rounding rules will
+ * correctly round rv + adj in some half-way cases.
+ * If rv * ulp(rv) is denormalized (i.e.,
+ * y <= (P-1)*Exp_msk1), we must adjust aadj to avoid
+ * trouble from bits lost to denormalization;
+ * example: 1.2e-307 .
+ */
+ #ifdef Avoid_Underflow
+ if (y <= P*Exp_msk1 && aadj > 1.)
+ #else
+ if (y <= (P-1)*Exp_msk1 && aadj > 1.)
+ #endif
+ {
+ aadj1 = (double)(int32)(aadj + 0.5);
+ if (!dsign)
+ aadj1 = -aadj1;
+ }
+ #ifdef Avoid_Underflow
+ if (scale && y <= P*Exp_msk1)
+ set_word0(aadj1, word0(aadj1) + (P+1)*Exp_msk1 - y);
+ #endif
+ adj = aadj1 * ulp(rv);
+ rv += adj;
+ #endif
+ }
+ z = word0(rv) & Exp_mask;
+ #ifdef Avoid_Underflow
+ if (!scale)
+ #endif
+ if (y == z) {
+ /* Can we stop now? */
+ L = (Long)aadj;
+ aadj -= L;
+ /* The tolerances below are conservative. */
+ if (dsign || word1(rv) || word0(rv) & Bndry_mask) {
+ if (aadj < .4999999 || aadj > .5000001)
+ break;
+ }
+ else if (aadj < .4999999/FLT_RADIX)
+ break;
+ }
+ cont:
+ Bfree(bb);
+ Bfree(bd);
+ Bfree(bs);
+ Bfree(delta);
+ bb = bd = bs = delta = NULL;
+ }
+ #ifdef Avoid_Underflow
+ if (scale) {
+ set_word0(rv0, Exp_1 - P*Exp_msk1);
+ set_word1(rv0, 0);
+ if ((word0(rv) & Exp_mask) <= P*Exp_msk1
+ && word1(rv) & 1
+ && dsign != 2) {
+ if (dsign) {
+ #ifdef Sudden_Underflow
+ /* rv will be 0, but this would give the */
+ /* right result if only rv *= rv0 worked. */
+ set_word0(rv, word0(rv) + P*Exp_msk1);
+ set_word0(rv0, Exp_1 - 2*P*Exp_msk1);
+ #endif
+ rv += ulp(rv);
+ }
+ else
+ set_word1(rv, word1(rv) & ~1);
+ }
+ rv *= rv0;
+ }
+ #endif /* Avoid_Underflow */
+ retfree:
+ Bfree(bb);
+ Bfree(bd);
+ Bfree(bs);
+ Bfree(bd0);
+ Bfree(delta);
+ ret:
+ RELEASE_DTOA_LOCK();
+ if (se)
+ *se = (char *)s;
+ return sign ? -rv : rv;
+
+ nomem:
+ Bfree(bb);
+ Bfree(bd);
+ Bfree(bs);
+ Bfree(bd0);
+ Bfree(delta);
+ *err = JS_DTOA_ENOMEM;
+ return 0;
+ }
+
+
+ /* Return floor(b/2^k) and set b to be the remainder. The returned quotient must be less than 2^32. */
+ static uint32 quorem2(Bigint *b, int32 k)
+ {
+ ULong mask;
+ ULong result;
+ ULong *bx, *bxe;
+ int32 w;
+ int32 n = k >> 5;
+ k &= 0x1F;
+ mask = (1<<k) - 1;
+
+ w = b->wds - n;
+ if (w <= 0)
+ return 0;
+ JS_ASSERT(w <= 2);
+ bx = b->x;
+ bxe = bx + n;
+ result = *bxe >> k;
+ *bxe &= mask;
+ if (w == 2) {
+ JS_ASSERT(!(bxe[1] & ~mask));
+ if (k)
+ result |= bxe[1] << (32 - k);
+ }
+ n++;
+ while (!*bxe && bxe != bx) {
+ n--;
+ bxe--;
+ }
+ b->wds = n;
+ return result;
+ }
+
+ /* Return floor(b/S) and set b to be the remainder. As added restrictions, b must not have
+ * more words than S, the most significant word of S must not start with a 1 bit, and the
+ * returned quotient must be less than 36. */
+ static int32 quorem(Bigint *b, Bigint *S)
+ {
+ int32 n;
+ ULong *bx, *bxe, q, *sx, *sxe;
+ #ifdef ULLong
+ ULLong borrow, carry, y, ys;
+ #else
+ ULong borrow, carry, y, ys;
+ ULong si, z, zs;
+ #endif
+
+ n = S->wds;
+ JS_ASSERT(b->wds <= n);
+ if (b->wds < n)
+ return 0;
+ sx = S->x;
+ sxe = sx + --n;
+ bx = b->x;
+ bxe = bx + n;
+ JS_ASSERT(*sxe <= 0x7FFFFFFF);
+ q = *bxe / (*sxe + 1); /* ensure q <= true quotient */
+ JS_ASSERT(q < 36);
+ if (q) {
+ borrow = 0;
+ carry = 0;
+ do {
+ #ifdef ULLong
+ ys = *sx++ * (ULLong)q + carry;
+ carry = ys >> 32;
+ y = *bx - (ys & 0xffffffffUL) - borrow;
+ borrow = y >> 32 & 1UL;
+ *bx++ = (ULong)(y & 0xffffffffUL);
+ #else
+ si = *sx++;
+ ys = (si & 0xffff) * q + carry;
+ zs = (si >> 16) * q + (ys >> 16);
+ carry = zs >> 16;
+ y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
+ borrow = (y & 0x10000) >> 16;
+ z = (*bx >> 16) - (zs & 0xffff) - borrow;
+ borrow = (z & 0x10000) >> 16;
+ Storeinc(bx, z, y);
+ #endif
+ }
+ while(sx <= sxe);
+ if (!*bxe) {
+ bx = b->x;
+ while(--bxe > bx && !*bxe)
+ --n;
+ b->wds = n;
+ }
+ }
+ if (cmp(b, S) >= 0) {
+ q++;
+ borrow = 0;
+ carry = 0;
+ bx = b->x;
+ sx = S->x;
+ do {
+ #ifdef ULLong
+ ys = *sx++ + carry;
+ carry = ys >> 32;
+ y = *bx - (ys & 0xffffffffUL) - borrow;
+ borrow = y >> 32 & 1UL;
+ *bx++ = (ULong)(y & 0xffffffffUL);
+ #else
+ si = *sx++;
+ ys = (si & 0xffff) + carry;
+ zs = (si >> 16) + (ys >> 16);
+ carry = zs >> 16;
+ y = (*bx & 0xffff) - (ys & 0xffff) - borrow;
+ borrow = (y & 0x10000) >> 16;
+ z = (*bx >> 16) - (zs & 0xffff) - borrow;
+ borrow = (z & 0x10000) >> 16;
+ Storeinc(bx, z, y);
+ #endif
+ } while(sx <= sxe);
+ bx = b->x;
+ bxe = bx + n;
+ if (!*bxe) {
+ while(--bxe > bx && !*bxe)
+ --n;
+ b->wds = n;
+ }
+ }
+ return (int32)q;
+ }
+
+ /* dtoa for IEEE arithmetic (dmg): convert double to ASCII string.
+ *
+ * Inspired by "How to Print Floating-Point Numbers Accurately" by
+ * Guy L. Steele, Jr. and Jon L. White [Proc. ACM SIGPLAN '90, pp. 92-101].
+ *
+ * Modifications:
+ * 1. Rather than iterating, we use a simple numeric overestimate
+ * to determine k = floor(log10(d)). We scale relevant
+ * quantities using O(log2(k)) rather than O(k) multiplications.
+ * 2. For some modes > 2 (corresponding to ecvt and fcvt), we don't
+ * try to generate digits strictly left to right. Instead, we
+ * compute with fewer bits and propagate the carry if necessary
+ * when rounding the final digit up. This is often faster.
+ * 3. Under the assumption that input will be rounded nearest,
+ * mode 0 renders 1e23 as 1e23 rather than 9.999999999999999e22.
+ * That is, we allow equality in stopping tests when the
+ * round-nearest rule will give the same floating-point value
+ * as would satisfaction of the stopping test with strict
+ * inequality.
+ * 4. We remove common factors of powers of 2 from relevant
+ * quantities.
+ * 5. When converting floating-point integers less than 1e16,
+ * we use floating-point arithmetic rather than resorting
+ * to multiple-precision integers.
+ * 6. When asked to produce fewer than 15 digits, we first try
+ * to get by with floating-point arithmetic; we resort to
+ * multiple-precision integer arithmetic only if we cannot
+ * guarantee that the floating-point calculation has given
+ * the correctly rounded result. For k requested digits and
+ * "uniformly" distributed input, the probability is
+ * something like 10^(k-15) that we must resort to the Long
+ * calculation.
+ */
+
+ /* Always emits at least one digit. */
+ /* If biasUp is set, then rounding in modes 2 and 3 will round away from zero
+ * when the number is exactly halfway between two representable values. For example,
+ * rounding 2.5 to zero digits after the decimal point will return 3 and not 2.
+ * 2.49 will still round to 2, and 2.51 will still round to 3. */
+ /* bufsize should be at least 20 for modes 0 and 1. For the other modes,
+ * bufsize should be two greater than the maximum number of output characters expected. */
+ static JSBool
+ js_dtoa(double d, int mode, JSBool biasUp, int ndigits,
+ int *decpt, int *sign, char **rve, char *buf, size_t bufsize)
+ {
+ /* Arguments ndigits, decpt, sign are similar to those
+ of ecvt and fcvt; trailing zeros are suppressed from
+ the returned string. If not null, *rve is set to point
+ to the end of the return value. If d is +-Infinity or NaN,
+ then *decpt is set to 9999.
+
+ mode:
+ 0 ==> shortest string that yields d when read in
+ and rounded to nearest.
+ 1 ==> like 0, but with Steele & White stopping rule;
+ e.g. with IEEE P754 arithmetic , mode 0 gives
+ 1e23 whereas mode 1 gives 9.999999999999999e22.
+ 2 ==> max(1,ndigits) significant digits. This gives a
+ return value similar to that of ecvt, except
+ that trailing zeros are suppressed.
+ 3 ==> through ndigits past the decimal point. This
+ gives a return value similar to that from fcvt,
+ except that trailing zeros are suppressed, and
+ ndigits can be negative.
+ 4-9 should give the same return values as 2-3, i.e.,
+ 4 <= mode <= 9 ==> same return as mode
+ 2 + (mode & 1). These modes are mainly for
+ debugging; often they run slower but sometimes
+ faster than modes 2-3.
+ 4,5,8,9 ==> left-to-right digit generation.
+ 6-9 ==> don't try fast floating-point estimate
+ (if applicable).
+
+ Values of mode other than 0-9 are treated as mode 0.
+
+ Sufficient space is allocated to the return value
+ to hold the suppressed trailing zeros.
+ */
+
+ int32 bbits, b2, b5, be, dig, i, ieps, ilim, ilim0, ilim1,
+ j, j1, k, k0, k_check, leftright, m2, m5, s2, s5,
+ spec_case, try_quick;
+ Long L;
+ #ifndef Sudden_Underflow
+ int32 denorm;
+ ULong x;
+ #endif
+ Bigint *b, *b1, *delta, *mlo, *mhi, *S;
+ double d2, ds, eps;
+ char *s;
+
+ if (word0(d) & Sign_bit) {
+ /* set sign for everything, including 0's and NaNs */
+ *sign = 1;
+ set_word0(d, word0(d) & ~Sign_bit); /* clear sign bit */
+ }
+ else
+ *sign = 0;
+
+ if ((word0(d) & Exp_mask) == Exp_mask) {
+ /* Infinity or NaN */
+ *decpt = 9999;
+ s = !word1(d) && !(word0(d) & Frac_mask) ? "Infinity" : "NaN";
+ if ((s[0] == 'I' && bufsize < 9) || (s[0] == 'N' && bufsize < 4)) {
+ JS_ASSERT(JS_FALSE);
+ /* JS_SetError(JS_BUFFER_OVERFLOW_ERROR, 0); */
+ return JS_FALSE;
+ }
+ strcpy(buf, s);
+ if (rve) {
+ *rve = buf[3] ? buf + 8 : buf + 3;
+ JS_ASSERT(**rve == '\0');
+ }
+ return JS_TRUE;
+ }
+
+ b = NULL; /* initialize for abort protection */
+ S = NULL;
+ mlo = mhi = NULL;
+
+ if (!d) {
+ no_digits:
+ *decpt = 1;
+ if (bufsize < 2) {
+ JS_ASSERT(JS_FALSE);
+ /* JS_SetError(JS_BUFFER_OVERFLOW_ERROR, 0); */
+ return JS_FALSE;
+ }
+ buf[0] = '0'; buf[1] = '\0'; /* copy "0" to buffer */
+ if (rve)
+ *rve = buf + 1;
+ /* We might have jumped to "no_digits" from below, so we need
+ * to be sure to free the potentially allocated Bigints to avoid
+ * memory leaks. */
+ Bfree(b);
+ Bfree(S);
+ if (mlo != mhi)
+ Bfree(mlo);
+ Bfree(mhi);
+ return JS_TRUE;
+ }
+
+ b = d2b(d, &be, &bbits);
+ if (!b)
+ goto nomem;
+ #ifdef Sudden_Underflow
+ i = (int32)(word0(d) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
+ #else
+ if ((i = (int32)(word0(d) >> Exp_shift1 & (Exp_mask>>Exp_shift1))) != 0) {
+ #endif
+ d2 = d;
+ set_word0(d2, word0(d2) & Frac_mask1);
+ set_word0(d2, word0(d2) | Exp_11);
+
+ /* log(x) ~=~ log(1.5) + (x-1.5)/1.5
+ * log10(x) = log(x) / log(10)
+ * ~=~ log(1.5)/log(10) + (x-1.5)/(1.5*log(10))
+ * log10(d) = (i-Bias)*log(2)/log(10) + log10(d2)
+ *
+ * This suggests computing an approximation k to log10(d) by
+ *
+ * k = (i - Bias)*0.301029995663981
+ * + ( (d2-1.5)*0.289529654602168 + 0.176091259055681 );
+ *
+ * We want k to be too large rather than too small.
+ * The error in the first-order Taylor series approximation
+ * is in our favor, so we just round up the constant enough
+ * to compensate for any error in the multiplication of
+ * (i - Bias) by 0.301029995663981; since |i - Bias| <= 1077,
+ * and 1077 * 0.30103 * 2^-52 ~=~ 7.2e-14,
+ * adding 1e-13 to the constant term more than suffices.
+ * Hence we adjust the constant term to 0.1760912590558.
+ * (We could get a more accurate k by invoking log10,
+ * but this is probably not worthwhile.)
+ */
+
+ i -= Bias;
+ #ifndef Sudden_Underflow
+ denorm = 0;
+ }
+ else {
+ /* d is denormalized */
+
+ i = bbits + be + (Bias + (P-1) - 1);
+ x = i > 32 ? word0(d) << (64 - i) | word1(d) >> (i - 32) : word1(d) << (32 - i);
+ d2 = x;
+ set_word0(d2, word0(d2) - 31*Exp_msk1); /* adjust exponent */
+ i -= (Bias + (P-1) - 1) + 1;
+ denorm = 1;
+ }
+ #endif
+ /* At this point d = f*2^i, where 1 <= f < 2. d2 is an approximation of f. */
+ ds = (d2-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
+ k = (int32)ds;
+ if (ds < 0. && ds != k)
+ k--; /* want k = floor(ds) */
+ k_check = 1;
+ if (k >= 0 && k <= Ten_pmax) {
+ if (d < tens[k])
+ k--;
+ k_check = 0;
+ }
+ /* At this point floor(log10(d)) <= k <= floor(log10(d))+1.
+ If k_check is zero, we're guaranteed that k = floor(log10(d)). */
+ j = bbits - i - 1;
+ /* At this point d = b/2^j, where b is an odd integer. */
+ if (j >= 0) {
+ b2 = 0;
+ s2 = j;
+ }
+ else {
+ b2 = -j;
+ s2 = 0;
+ }
+ if (k >= 0) {
+ b5 = 0;
+ s5 = k;
+ s2 += k;
+ }
+ else {
+ b2 -= k;
+ b5 = -k;
+ s5 = 0;
+ }
+ /* At this point d/10^k = (b * 2^b2 * 5^b5) / (2^s2 * 5^s5), where b is an odd integer,
+ b2 >= 0, b5 >= 0, s2 >= 0, and s5 >= 0. */
+ if (mode < 0 || mode > 9)
+ mode = 0;
+ try_quick = 1;
+ if (mode > 5) {
+ mode -= 4;
+ try_quick = 0;
+ }
+ leftright = 1;
+ ilim = ilim1 = 0;
+ switch(mode) {
+ case 0:
+ case 1:
+ ilim = ilim1 = -1;
+ i = 18;
+ ndigits = 0;
+ break;
+ case 2:
+ leftright = 0;
+ /* no break */
+ case 4:
+ if (ndigits <= 0)
+ ndigits = 1;
+ ilim = ilim1 = i = ndigits;
+ break;
+ case 3:
+ leftright = 0;
+ /* no break */
+ case 5:
+ i = ndigits + k + 1;
+ ilim = i;
+ ilim1 = i - 1;
+ if (i <= 0)
+ i = 1;
+ }
+ /* ilim is the maximum number of significant digits we want, based on k and ndigits. */
+ /* ilim1 is the maximum number of significant digits we want, based on k and ndigits,
+ when it turns out that k was computed too high by one. */
+
+ /* Ensure space for at least i+1 characters, including trailing null. */
+ if (bufsize <= (size_t)i) {
+ Bfree(b);
+ JS_ASSERT(JS_FALSE);
+ return JS_FALSE;
+ }
+ s = buf;
+
+ if (ilim >= 0 && ilim <= Quick_max && try_quick) {
+
+ /* Try to get by with floating-point arithmetic. */
+
+ i = 0;
+ d2 = d;
+ k0 = k;
+ ilim0 = ilim;
+ ieps = 2; /* conservative */
+ /* Divide d by 10^k, keeping track of the roundoff error and avoiding overflows. */
+ if (k > 0) {
+ ds = tens[k&0xf];
+ j = k >> 4;
+ if (j & Bletch) {
+ /* prevent overflows */
+ j &= Bletch - 1;
+ d /= bigtens[n_bigtens-1];
+ ieps++;
+ }
+ for(; j; j >>= 1, i++)
+ if (j & 1) {
+ ieps++;
+ ds *= bigtens[i];
+ }
+ d /= ds;
+ }
+ else if ((j1 = -k) != 0) {
+ d *= tens[j1 & 0xf];
+ for(j = j1 >> 4; j; j >>= 1, i++)
+ if (j & 1) {
+ ieps++;
+ d *= bigtens[i];
+ }
+ }
+ /* Check that k was computed correctly. */
+ if (k_check && d < 1. && ilim > 0) {
+ if (ilim1 <= 0)
+ goto fast_failed;
+ ilim = ilim1;
+ k--;
+ d *= 10.;
+ ieps++;
+ }
+ /* eps bounds the cumulative error. */
+ eps = ieps*d + 7.;
+ set_word0(eps, word0(eps) - (P-1)*Exp_msk1);
+ if (ilim == 0) {
+ S = mhi = 0;
+ d -= 5.;
+ if (d > eps)
+ goto one_digit;
+ if (d < -eps)
+ goto no_digits;
+ goto fast_failed;
+ }
+ #ifndef No_leftright
+ if (leftright) {
+ /* Use Steele & White method of only
+ * generating digits needed.
+ */
+ eps = 0.5/tens[ilim-1] - eps;
+ for(i = 0;;) {
+ L = (Long)d;
+ d -= L;
+ *s++ = '0' + (char)L;
+ if (d < eps)
+ goto ret1;
+ if (1. - d < eps)
+ goto bump_up;
+ if (++i >= ilim)
+ break;
+ eps *= 10.;
+ d *= 10.;
+ }
+ }
+ else {
+ #endif
+ /* Generate ilim digits, then fix them up. */
+ eps *= tens[ilim-1];
+ for(i = 1;; i++, d *= 10.) {
+ L = (Long)d;
+ d -= L;
+ *s++ = '0' + (char)L;
+ if (i == ilim) {
+ if (d > 0.5 + eps)
+ goto bump_up;
+ else if (d < 0.5 - eps) {
+ while(*--s == '0') ;
+ s++;
+ goto ret1;
+ }
+ break;
+ }
+ }
+ #ifndef No_leftright
+ }
+ #endif
+ fast_failed:
+ s = buf;
+ d = d2;
+ k = k0;
+ ilim = ilim0;
+ }
+
+ /* Do we have a "small" integer? */
+
+ if (be >= 0 && k <= Int_max) {
+ /* Yes. */
+ ds = tens[k];
+ if (ndigits < 0 && ilim <= 0) {
+ S = mhi = 0;
+ if (ilim < 0 || d < 5*ds || (!biasUp && d == 5*ds))
+ goto no_digits;
+ goto one_digit;
+ }
+ for(i = 1;; i++) {
+ L = (Long) (d / ds);
+ d -= L*ds;
+ #ifdef Check_FLT_ROUNDS
+ /* If FLT_ROUNDS == 2, L will usually be high by 1 */
+ if (d < 0) {
+ L--;
+ d += ds;
+ }
+ #endif
+ *s++ = '0' + (char)L;
+ if (i == ilim) {
+ d += d;
+ if ((d > ds) || (d == ds && (L & 1 || biasUp))) {
+ bump_up:
+ while(*--s == '9')
+ if (s == buf) {
+ k++;
+ *s = '0';
+ break;
+ }
+ ++*s++;
+ }
+ break;
+ }
+ if (!(d *= 10.))
+ break;
+ }
+ goto ret1;
+ }
+
+ m2 = b2;
+ m5 = b5;
+ if (leftright) {
+ if (mode < 2) {
+ i =
+ #ifndef Sudden_Underflow
+ denorm ? be + (Bias + (P-1) - 1 + 1) :
+ #endif
+ 1 + P - bbits;
+ /* i is 1 plus the number of trailing zero bits in d's significand. Thus,
+ (2^m2 * 5^m5) / (2^(s2+i) * 5^s5) = (1/2 lsb of d)/10^k. */
+ }
+ else {
+ j = ilim - 1;
+ if (m5 >= j)
+ m5 -= j;
+ else {
+ s5 += j -= m5;
+ b5 += j;
+ m5 = 0;
+ }
+ if ((i = ilim) < 0) {
+ m2 -= i;
+ i = 0;
+ }
+ /* (2^m2 * 5^m5) / (2^(s2+i) * 5^s5) = (1/2 * 10^(1-ilim))/10^k. */
+ }
+ b2 += i;
+ s2 += i;
+ mhi = i2b(1);
+ if (!mhi)
+ goto nomem;
+ /* (mhi * 2^m2 * 5^m5) / (2^s2 * 5^s5) = one-half of last printed (when mode >= 2) or
+ input (when mode < 2) significant digit, divided by 10^k. */
+ }
+ /* We still have d/10^k = (b * 2^b2 * 5^b5) / (2^s2 * 5^s5). Reduce common factors in
+ b2, m2, and s2 without changing the equalities. */
+ if (m2 > 0 && s2 > 0) {
+ i = m2 < s2 ? m2 : s2;
+ b2 -= i;
+ m2 -= i;
+ s2 -= i;
+ }
+
+ /* Fold b5 into b and m5 into mhi. */
+ if (b5 > 0) {
+ if (leftright) {
+ if (m5 > 0) {
+ mhi = pow5mult(mhi, m5);
+ if (!mhi)
+ goto nomem;
+ b1 = mult(mhi, b);
+ if (!b1)
+ goto nomem;
+ Bfree(b);
+ b = b1;
+ }
+ if ((j = b5 - m5) != 0) {
+ b = pow5mult(b, j);
+ if (!b)
+ goto nomem;
+ }
+ }
+ else {
+ b = pow5mult(b, b5);
+ if (!b)
+ goto nomem;
+ }
+ }
+ /* Now we have d/10^k = (b * 2^b2) / (2^s2 * 5^s5) and
+ (mhi * 2^m2) / (2^s2 * 5^s5) = one-half of last printed or input significant digit, divided by 10^k. */
+
+ S = i2b(1);
+ if (!S)
+ goto nomem;
+ if (s5 > 0) {
+ S = pow5mult(S, s5);
+ if (!S)
+ goto nomem;
+ }
+ /* Now we have d/10^k = (b * 2^b2) / (S * 2^s2) and
+ (mhi * 2^m2) / (S * 2^s2) = one-half of last printed or input significant digit, divided by 10^k. */
+
+ /* Check for special case that d is a normalized power of 2. */
+ spec_case = 0;
+ if (mode < 2) {
+ if (!word1(d) && !(word0(d) & Bndry_mask)
+ #ifndef Sudden_Underflow
+ && word0(d) & (Exp_mask & Exp_mask << 1)
+ #endif
+ ) {
+ /* The special case. Here we want to be within a quarter of the last input
+ significant digit instead of one half of it when the decimal output string's value is less than d. */
+ b2 += Log2P;
+ s2 += Log2P;
+ spec_case = 1;
+ }
+ }
+
+ /* Arrange for convenient computation of quotients:
+ * shift left if necessary so divisor has 4 leading 0 bits.
+ *
+ * Perhaps we should just compute leading 28 bits of S once
+ * and for all and pass them and a shift to quorem, so it
+ * can do shifts and ors to compute the numerator for q.
+ */
+ if ((i = ((s5 ? 32 - hi0bits(S->x[S->wds-1]) : 1) + s2) & 0x1f) != 0)
+ i = 32 - i;
+ /* i is the number of leading zero bits in the most significant word of S*2^s2. */
+ if (i > 4) {
+ i -= 4;
+ b2 += i;
+ m2 += i;
+ s2 += i;
+ }
+ else if (i < 4) {
+ i += 28;
+ b2 += i;
+ m2 += i;
+ s2 += i;
+ }
+ /* Now S*2^s2 has exactly four leading zero bits in its most significant word. */
+ if (b2 > 0) {
+ b = lshift(b, b2);
+ if (!b)
+ goto nomem;
+ }
+ if (s2 > 0) {
+ S = lshift(S, s2);
+ if (!S)
+ goto nomem;
+ }
+ /* Now we have d/10^k = b/S and
+ (mhi * 2^m2) / S = maximum acceptable error, divided by 10^k. */
+ if (k_check) {
+ if (cmp(b,S) < 0) {
+ k--;
+ b = multadd(b, 10, 0); /* we botched the k estimate */
+ if (!b)
+ goto nomem;
+ if (leftright) {
+ mhi = multadd(mhi, 10, 0);
+ if (!mhi)
+ goto nomem;
+ }
+ ilim = ilim1;
+ }
+ }
+ /* At this point 1 <= d/10^k = b/S < 10. */
+
+ if (ilim <= 0 && mode > 2) {
+ /* We're doing fixed-mode output and d is less than the minimum nonzero output in this mode.
+ Output either zero or the minimum nonzero output depending on which is closer to d. */
+ if (ilim < 0)
+ goto no_digits;
+ S = multadd(S,5,0);
+ if (!S)
+ goto nomem;
+ i = cmp(b,S);
+ if (i < 0 || (i == 0 && !biasUp)) {
+ /* Always emit at least one digit. If the number appears to be zero
+ using the current mode, then emit one '0' digit and set decpt to 1. */
+ /*no_digits:
+ k = -1 - ndigits;
+ goto ret; */
+ goto no_digits;
+ }
+ one_digit:
+ *s++ = '1';
+ k++;
+ goto ret;
+ }
+ if (leftright) {
+ if (m2 > 0) {
+ mhi = lshift(mhi, m2);
+ if (!mhi)
+ goto nomem;
+ }
+
+ /* Compute mlo -- check for special case
+ * that d is a normalized power of 2.
+ */
+
+ mlo = mhi;
+ if (spec_case) {
+ mhi = Balloc(mhi->k);
+ if (!mhi)
+ goto nomem;
+ Bcopy(mhi, mlo);
+ mhi = lshift(mhi, Log2P);
+ if (!mhi)
+ goto nomem;
+ }
+ /* mlo/S = maximum acceptable error, divided by 10^k, if the output is less than d. */
+ /* mhi/S = maximum acceptable error, divided by 10^k, if the output is greater than d. */
+
+ for(i = 1;;i++) {
+ dig = quorem(b,S) + '0';
+ /* Do we yet have the shortest decimal string
+ * that will round to d?
+ */
+ j = cmp(b, mlo);
+ /* j is b/S compared with mlo/S. */
+ delta = diff(S, mhi);
+ if (!delta)
+ goto nomem;
+ j1 = delta->sign ? 1 : cmp(b, delta);
+ Bfree(delta);
+ /* j1 is b/S compared with 1 - mhi/S. */
+ #ifndef ROUND_BIASED
+ if (j1 == 0 && !mode && !(word1(d) & 1)) {
+ if (dig == '9')
+ goto round_9_up;
+ if (j > 0)
+ dig++;
+ *s++ = (char)dig;
+ goto ret;
+ }
+ #endif
+ if ((j < 0) || (j == 0 && !mode
+ #ifndef ROUND_BIASED
+ && !(word1(d) & 1)
+ #endif
+ )) {
+ if (j1 > 0) {
+ /* Either dig or dig+1 would work here as the least significant decimal digit.
+ Use whichever would produce a decimal value closer to d. */
+ b = lshift(b, 1);
+ if (!b)
+ goto nomem;
+ j1 = cmp(b, S);
+ if (((j1 > 0) || (j1 == 0 && (dig & 1 || biasUp)))
+ && (dig++ == '9'))
+ goto round_9_up;
+ }
+ *s++ = (char)dig;
+ goto ret;
+ }
+ if (j1 > 0) {
+ if (dig == '9') { /* possible if i == 1 */
+ round_9_up:
+ *s++ = '9';
+ goto roundoff;
+ }
+ *s++ = (char)dig + 1;
+ goto ret;
+ }
+ *s++ = (char)dig;
+ if (i == ilim)
+ break;
+ b = multadd(b, 10, 0);
+ if (!b)
+ goto nomem;
+ if (mlo == mhi) {
+ mlo = mhi = multadd(mhi, 10, 0);
+ if (!mhi)
+ goto nomem;
+ }
+ else {
+ mlo = multadd(mlo, 10, 0);
+ if (!mlo)
+ goto nomem;
+ mhi = multadd(mhi, 10, 0);
+ if (!mhi)
+ goto nomem;
+ }
+ }
+ }
+ else
+ for(i = 1;; i++) {
+ *s++ = (char)(dig = quorem(b,S) + '0');
+ if (i >= ilim)
+ break;
+ b = multadd(b, 10, 0);
+ if (!b)
+ goto nomem;
+ }
+
+ /* Round off last digit */
+
+ b = lshift(b, 1);
+ if (!b)
+ goto nomem;
+ j = cmp(b, S);
+ if ((j > 0) || (j == 0 && (dig & 1 || biasUp))) {
+ roundoff:
+ while(*--s == '9')
+ if (s == buf) {
+ k++;
+ *s++ = '1';
+ goto ret;
+ }
+ ++*s++;
+ }
+ else {
+ /* Strip trailing zeros */
+ while(*--s == '0') ;
+ s++;
+ }
+ ret:
+ Bfree(S);
+ if (mhi) {
+ if (mlo && mlo != mhi)
+ Bfree(mlo);
+ Bfree(mhi);
+ }
+ ret1:
+ Bfree(b);
+ JS_ASSERT(s < buf + bufsize);
+ *s = '\0';
+ if (rve)
+ *rve = s;
+ *decpt = k + 1;
+ return JS_TRUE;
+
+ nomem:
+ Bfree(S);
+ if (mhi) {
+ if (mlo && mlo != mhi)
+ Bfree(mlo);
+ Bfree(mhi);
+ }
+ Bfree(b);
+ return JS_FALSE;
+ }
+
+
+ /* Mapping of JSDToStrMode -> js_dtoa mode */
+ static const int dtoaModes[] = {
+ 0, /* DTOSTR_STANDARD */
+ 0, /* DTOSTR_STANDARD_EXPONENTIAL, */
+ 3, /* DTOSTR_FIXED, */
+ 2, /* DTOSTR_EXPONENTIAL, */
+ 2}; /* DTOSTR_PRECISION */
+
+ JS_FRIEND_API(char *)
+ JS_dtostr(char *buffer, size_t bufferSize, JSDToStrMode mode, int precision, double d)
+ {
+ int decPt; /* Position of decimal point relative to first digit returned by js_dtoa */
+ int sign; /* Nonzero if the sign bit was set in d */
+ int nDigits; /* Number of significand digits returned by js_dtoa */
+ char *numBegin = buffer+2; /* Pointer to the digits returned by js_dtoa; the +2 leaves space for */
+ /* the sign and/or decimal point */
+ char *numEnd; /* Pointer past the digits returned by js_dtoa */
+ JSBool dtoaRet;
+
+ JS_ASSERT(bufferSize >= (size_t)(mode <= DTOSTR_STANDARD_EXPONENTIAL ? DTOSTR_STANDARD_BUFFER_SIZE :
+ DTOSTR_VARIABLE_BUFFER_SIZE(precision)));
+
+ if (mode == DTOSTR_FIXED && (d >= 1e21 || d <= -1e21))
+ mode = DTOSTR_STANDARD; /* Change mode here rather than below because the buffer may not be large enough to hold a large integer. */
+
+ /* Locking for Balloc's shared buffers */
+ ACQUIRE_DTOA_LOCK();
+ dtoaRet = js_dtoa(d, dtoaModes[mode], mode >= DTOSTR_FIXED, precision, &decPt, &sign, &numEnd, numBegin, bufferSize-2);
+ RELEASE_DTOA_LOCK();
+ if (!dtoaRet)
+ return 0;
+
+ nDigits = numEnd - numBegin;
+
+ /* If Infinity, -Infinity, or NaN, return the string regardless of the mode. */
+ if (decPt != 9999) {
+ JSBool exponentialNotation = JS_FALSE;
+ int minNDigits = 0; /* Minimum number of significand digits required by mode and precision */
+ char *p;
+ char *q;
+
+ switch (mode) {
+ case DTOSTR_STANDARD:
+ if (decPt < -5 || decPt > 21)
+ exponentialNotation = JS_TRUE;
+ else
+ minNDigits = decPt;
+ break;
+
+ case DTOSTR_FIXED:
+ if (precision >= 0)
+ minNDigits = decPt + precision;
+ else
+ minNDigits = decPt;
+ break;
+
+ case DTOSTR_EXPONENTIAL:
+ JS_ASSERT(precision > 0);
+ minNDigits = precision;
+ /* Fall through */
+ case DTOSTR_STANDARD_EXPONENTIAL:
+ exponentialNotation = JS_TRUE;
+ break;
+
+ case DTOSTR_PRECISION:
+ JS_ASSERT(precision > 0);
+ minNDigits = precision;
+ if (decPt < -5 || decPt > precision)
+ exponentialNotation = JS_TRUE;
+ break;
+ }
+
+ /* If the number has fewer than minNDigits, pad it with zeros at the end */
+ if (nDigits < minNDigits) {
+ p = numBegin + minNDigits;
+ nDigits = minNDigits;
+ do {
+ *numEnd++ = '0';
+ } while (numEnd != p);
+ *numEnd = '\0';
+ }
+
+ if (exponentialNotation) {
+ /* Insert a decimal point if more than one significand digit */
+ if (nDigits != 1) {
+ numBegin--;
+ numBegin[0] = numBegin[1];
+ numBegin[1] = '.';
+ }
+ JS_snprintf(numEnd, bufferSize - (numEnd - buffer), "e%+d", decPt-1);
+ } else if (decPt != nDigits) {
+ /* Some kind of a fraction in fixed notation */
+ JS_ASSERT(decPt <= nDigits);
+ if (decPt > 0) {
+ /* dd...dd . dd...dd */
+ p = --numBegin;
+ do {
+ *p = p[1];
+ p++;
+ } while (--decPt);
+ *p = '.';
+ } else {
+ /* 0 . 00...00dd...dd */
+ p = numEnd;
+ numEnd += 1 - decPt;
+ q = numEnd;
+ JS_ASSERT(numEnd < buffer + bufferSize);
+ *numEnd = '\0';
+ while (p != numBegin)
+ *--q = *--p;
+ for (p = numBegin + 1; p != q; p++)
+ *p = '0';
+ *numBegin = '.';
+ *--numBegin = '0';
+ }
+ }
+ }
+
+ /* If negative and neither -0.0 nor NaN, output a leading '-'. */
+ if (sign &&
+ !(word0(d) == Sign_bit && word1(d) == 0) &&
+ !((word0(d) & Exp_mask) == Exp_mask &&
+ (word1(d) || (word0(d) & Frac_mask)))) {
+ *--numBegin = '-';
+ }
+ return numBegin;
+ }
+
+
+ /* Let b = floor(b / divisor), and return the remainder. b must be nonnegative.
+ * divisor must be between 1 and 65536.
+ * This function cannot run out of memory. */
+ static uint32
+ divrem(Bigint *b, uint32 divisor)
+ {
+ int32 n = b->wds;
+ uint32 remainder = 0;
+ ULong *bx;
+ ULong *bp;
+
+ JS_ASSERT(divisor > 0 && divisor <= 65536);
+
+ if (!n)
+ return 0; /* b is zero */
+ bx = b->x;
+ bp = bx + n;
+ do {
+ ULong a = *--bp;
+ ULong dividend = remainder << 16 | a >> 16;
+ ULong quotientHi = dividend / divisor;
+ ULong quotientLo;
+
+ remainder = dividend - quotientHi*divisor;
+ JS_ASSERT(quotientHi <= 0xFFFF && remainder < divisor);
+ dividend = remainder << 16 | (a & 0xFFFF);
+ quotientLo = dividend / divisor;
+ remainder = dividend - quotientLo*divisor;
+ JS_ASSERT(quotientLo <= 0xFFFF && remainder < divisor);
+ *bp = quotientHi << 16 | quotientLo;
+ } while (bp != bx);
+ /* Decrease the size of the number if its most significant word is now zero. */
+ if (bx[n-1] == 0)
+ b->wds--;
+ return remainder;
+ }
+
+
+ /* "-0.0000...(1073 zeros after decimal point)...0001\0" is the longest string that we could produce,
+ * which occurs when printing -5e-324 in binary. We could compute a better estimate of the size of
+ * the output string and malloc fewer bytes depending on d and base, but why bother? */
+ #define DTOBASESTR_BUFFER_SIZE 1078
+ #define BASEDIGIT(digit) ((char)(((digit) >= 10) ? 'a' - 10 + (digit) : '0' + (digit)))
+
+ JS_FRIEND_API(char *)
+ JS_dtobasestr(int base, double d)
+ {
+ char *buffer; /* The output string */
+ char *p; /* Pointer to current position in the buffer */
+ char *pInt; /* Pointer to the beginning of the integer part of the string */
+ char *q;
+ uint32 digit;
+ double di; /* d truncated to an integer */
+ double df; /* The fractional part of d */
+
+ JS_ASSERT(base >= 2 && base <= 36);
+
+ buffer = (char*) malloc(DTOBASESTR_BUFFER_SIZE);
+ if (buffer) {
+ p = buffer;
+ if (d < 0.0
+ #if defined(XP_WIN) || defined(XP_OS2)
+ && !((word0(d) & Exp_mask) == Exp_mask && ((word0(d) & Frac_mask) || word1(d))) /* Visual C++ doesn't know how to compare against NaN */
+ #endif
+ ) {
+ *p++ = '-';
+ d = -d;
+ }
+
+ /* Check for Infinity and NaN */
+ if ((word0(d) & Exp_mask) == Exp_mask) {
+ strcpy(p, !word1(d) && !(word0(d) & Frac_mask) ? "Infinity" : "NaN");
+ return buffer;
+ }
+
+ /* Locking for Balloc's shared buffers */
+ ACQUIRE_DTOA_LOCK();
+
+ /* Output the integer part of d with the digits in reverse order. */
+ pInt = p;
+ di = fd_floor(d);
+ if (di <= 4294967295.0) {
+ uint32 n = (uint32)di;
+ if (n)
+ do {
+ uint32 m = n / base;
+ digit = n - m*base;
+ n = m;
+ JS_ASSERT(digit < (uint32)base);
+ *p++ = BASEDIGIT(digit);
+ } while (n);
+ else *p++ = '0';
+ } else {
+ int32 e;
+ int32 bits; /* Number of significant bits in di; not used. */
+ Bigint *b = d2b(di, &e, &bits);
+ if (!b)
+ goto nomem1;
+ b = lshift(b, e);
+ if (!b) {
+ nomem1:
+ Bfree(b);
+ return NULL;
+ }
+ do {
+ digit = divrem(b, base);
+ JS_ASSERT(digit < (uint32)base);
+ *p++ = BASEDIGIT(digit);
+ } while (b->wds);
+ Bfree(b);
+ }
+ /* Reverse the digits of the integer part of d. */
+ q = p-1;
+ while (q > pInt) {
+ char ch = *pInt;
+ *pInt++ = *q;
+ *q-- = ch;
+ }
+
+ df = d - di;
+ if (df != 0.0) {
+ /* We have a fraction. */
+ int32 e, bbits, s2, done;
+ Bigint *b, *s, *mlo, *mhi;
+
+ b = s = mlo = mhi = NULL;
+
+ *p++ = '.';
+ b = d2b(df, &e, &bbits);
+ if (!b) {
+ nomem2:
+ Bfree(b);
+ Bfree(s);
+ if (mlo != mhi)
+ Bfree(mlo);
+ Bfree(mhi);
+ return NULL;
+ }
+ JS_ASSERT(e < 0);
+ /* At this point df = b * 2^e. e must be less than zero because 0 < df < 1. */
+
+ s2 = -(int32)(word0(d) >> Exp_shift1 & Exp_mask>>Exp_shift1);
+ #ifndef Sudden_Underflow
+ if (!s2)
+ s2 = -1;
+ #endif
+ s2 += Bias + P;
+ /* 1/2^s2 = (nextDouble(d) - d)/2 */
+ JS_ASSERT(-s2 < e);
+ mlo = i2b(1);
+ if (!mlo)
+ goto nomem2;
+ mhi = mlo;
+ if (!word1(d) && !(word0(d) & Bndry_mask)
+ #ifndef Sudden_Underflow
+ && word0(d) & (Exp_mask & Exp_mask << 1)
+ #endif
+ ) {
+ /* The special case. Here we want to be within a quarter of the last input
+ significant digit instead of one half of it when the output string's value is less than d. */
+ s2 += Log2P;
+ mhi = i2b(1<<Log2P);
+ if (!mhi)
+ goto nomem2;
+ }
+ b = lshift(b, e + s2);
+ if (!b)
+ goto nomem2;
+ s = i2b(1);
+ if (!s)
+ goto nomem2;
+ s = lshift(s, s2);
+ if (!s)
+ goto nomem2;
+ /* At this point we have the following:
+ * s = 2^s2;
+ * 1 > df = b/2^s2 > 0;
+ * (d - prevDouble(d))/2 = mlo/2^s2;
+ * (nextDouble(d) - d)/2 = mhi/2^s2. */
+
+ done = JS_FALSE;
+ do {
+ int32 j, j1;
+ Bigint *delta;
+
+ b = multadd(b, base, 0);
+ if (!b)
+ goto nomem2;
+ digit = quorem2(b, s2);
+ if (mlo == mhi) {
+ mlo = mhi = multadd(mlo, base, 0);
+ if (!mhi)
+ goto nomem2;
+ }
+ else {
+ mlo = multadd(mlo, base, 0);
+ if (!mlo)
+ goto nomem2;
+ mhi = multadd(mhi, base, 0);
+ if (!mhi)
+ goto nomem2;
+ }
+
+ /* Do we yet have the shortest string that will round to d? */
+ j = cmp(b, mlo);
+ /* j is b/2^s2 compared with mlo/2^s2. */
+ delta = diff(s, mhi);
+ if (!delta)
+ goto nomem2;
+ j1 = delta->sign ? 1 : cmp(b, delta);
+ Bfree(delta);
+ /* j1 is b/2^s2 compared with 1 - mhi/2^s2. */
+
+ #ifndef ROUND_BIASED
+ if (j1 == 0 && !(word1(d) & 1)) {
+ if (j > 0)
+ digit++;
+ done = JS_TRUE;
+ } else
+ #endif
+ if (j < 0 || (j == 0
+ #ifndef ROUND_BIASED
+ && !(word1(d) & 1)
+ #endif
+ )) {
+ if (j1 > 0) {
+ /* Either dig or dig+1 would work here as the least significant digit.
+ Use whichever would produce an output value closer to d. */
+ b = lshift(b, 1);
+ if (!b)
+ goto nomem2;
+ j1 = cmp(b, s);
+ if (j1 > 0) /* The even test (|| (j1 == 0 && (digit & 1))) is not here because it messes up odd base output
+ * such as 3.5 in base 3. */
+ digit++;
+ }
+ done = JS_TRUE;
+ } else if (j1 > 0) {
+ digit++;
+ done = JS_TRUE;
+ }
+ JS_ASSERT(digit < (uint32)base);
+ *p++ = BASEDIGIT(digit);
+ } while (!done);
+ Bfree(b);
+ Bfree(s);
+ if (mlo != mhi)
+ Bfree(mlo);
+ Bfree(mhi);
+ }
+ JS_ASSERT(p < buffer + DTOBASESTR_BUFFER_SIZE);
+ *p = '\0';
+ RELEASE_DTOA_LOCK();
+ }
+ return buffer;
+ }
|
