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+/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0
+ *
+ * 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 Rhino code, released
+ * May 6, 1999.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1997-1999
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ * Waldemar Horwat
+ * Roger Lawrence
+ * Attila Szegedi
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * the GNU General Public License Version 2 or later (the "GPL"), in which
+ * case the provisions of the GPL are applicable instead of those above. If
+ * you wish to allow use of your version of this file only under the terms of
+ * the GPL and not to allow others to use your version of this file under the
+ * MPL, indicate your decision by deleting the provisions above and replacing
+ * them with the notice and other provisions required by the GPL. If you do
+ * not delete the provisions above, a recipient may use your version of this
+ * file under either the MPL or the GPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+/****************************************************************
+ *
+ * The author of this software is David M. Gay.
+ *
+ * Copyright (c) 1991, 2000, 2001 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.
+ *
+ ***************************************************************/
+
+package org.mozilla.javascript;
+
+import java.math.BigInteger;
+
+class DToA {
+
+
+/* "-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? */
+
+ private static final int DTOBASESTR_BUFFER_SIZE = 1078;
+
+ private static char BASEDIGIT(int digit) {
+ return (char)((digit >= 10) ? 'a' - 10 + digit : '0' + digit);
+ }
+
+ static final int
+ DTOSTR_STANDARD = 0, /* Either fixed or exponential format; round-trip */
+ DTOSTR_STANDARD_EXPONENTIAL = 1, /* Always exponential format; round-trip */
+ DTOSTR_FIXED = 2, /* Round to <precision> digits after the decimal point; exponential if number is large */
+ DTOSTR_EXPONENTIAL = 3, /* Always exponential format; <precision> significant digits */
+ DTOSTR_PRECISION = 4; /* Either fixed or exponential format; <precision> significant digits */
+
+
+ private static final int Frac_mask = 0xfffff;
+ private static final int Exp_shift = 20;
+ private static final int Exp_msk1 = 0x100000;
+
+ private static final long Frac_maskL = 0xfffffffffffffL;
+ private static final int Exp_shiftL = 52;
+ private static final long Exp_msk1L = 0x10000000000000L;
+
+ private static final int Bias = 1023;
+ private static final int P = 53;
+
+ private static final int Exp_shift1 = 20;
+ private static final int Exp_mask = 0x7ff00000;
+ private static final int Exp_mask_shifted = 0x7ff;
+ private static final int Bndry_mask = 0xfffff;
+ private static final int Log2P = 1;
+
+ private static final int Sign_bit = 0x80000000;
+ private static final int Exp_11 = 0x3ff00000;
+ private static final int Ten_pmax = 22;
+ private static final int Quick_max = 14;
+ private static final int Bletch = 0x10;
+ private static final int Frac_mask1 = 0xfffff;
+ private static final int Int_max = 14;
+ private static final int n_bigtens = 5;
+
+
+ private static final 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
+ };
+
+ private static final double bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };
+
+ private static int lo0bits(int y)
+ {
+ int k;
+ int x = y;
+
+ if ((x & 7) != 0) {
+ if ((x & 1) != 0)
+ return 0;
+ if ((x & 2) != 0) {
+ return 1;
+ }
+ return 2;
+ }
+ k = 0;
+ if ((x & 0xffff) == 0) {
+ k = 16;
+ x >>>= 16;
+ }
+ if ((x & 0xff) == 0) {
+ k += 8;
+ x >>>= 8;
+ }
+ if ((x & 0xf) == 0) {
+ k += 4;
+ x >>>= 4;
+ }
+ if ((x & 0x3) == 0) {
+ k += 2;
+ x >>>= 2;
+ }
+ if ((x & 1) == 0) {
+ k++;
+ x >>>= 1;
+ if ((x & 1) == 0)
+ return 32;
+ }
+ return k;
+ }
+
+ /* Return the number (0 through 32) of most significant zero bits in x. */
+ private static int hi0bits(int x)
+ {
+ int k = 0;
+
+ if ((x & 0xffff0000) == 0) {
+ k = 16;
+ x <<= 16;
+ }
+ if ((x & 0xff000000) == 0) {
+ k += 8;
+ x <<= 8;
+ }
+ if ((x & 0xf0000000) == 0) {
+ k += 4;
+ x <<= 4;
+ }
+ if ((x & 0xc0000000) == 0) {
+ k += 2;
+ x <<= 2;
+ }
+ if ((x & 0x80000000) == 0) {
+ k++;
+ if ((x & 0x40000000) == 0)
+ return 32;
+ }
+ return k;
+ }
+
+ private static void stuffBits(byte bits[], int offset, int val)
+ {
+ bits[offset] = (byte)(val >> 24);
+ bits[offset + 1] = (byte)(val >> 16);
+ bits[offset + 2] = (byte)(val >> 8);
+ bits[offset + 3] = (byte)(val);
+ }
+
+ /* 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. */
+ private static BigInteger d2b(double d, int[] e, int[] bits)
+ {
+ byte dbl_bits[];
+ int i, k, y, z, de;
+ long dBits = Double.doubleToLongBits(d);
+ int d0 = (int)(dBits >>> 32);
+ int d1 = (int)(dBits);
+
+ z = d0 & Frac_mask;
+ d0 &= 0x7fffffff; /* clear sign bit, which we ignore */
+
+ if ((de = (d0 >>> Exp_shift)) != 0)
+ z |= Exp_msk1;
+
+ if ((y = d1) != 0) {
+ dbl_bits = new byte[8];
+ k = lo0bits(y);
+ y >>>= k;
+ if (k != 0) {
+ stuffBits(dbl_bits, 4, y | z << (32 - k));
+ z >>= k;
+ }
+ else
+ stuffBits(dbl_bits, 4, y);
+ stuffBits(dbl_bits, 0, z);
+ i = (z != 0) ? 2 : 1;
+ }
+ else {
+ // JS_ASSERT(z);
+ dbl_bits = new byte[4];
+ k = lo0bits(z);
+ z >>>= k;
+ stuffBits(dbl_bits, 0, z);
+ k += 32;
+ i = 1;
+ }
+ if (de != 0) {
+ e[0] = de - Bias - (P-1) + k;
+ bits[0] = P - k;
+ }
+ else {
+ e[0] = de - Bias - (P-1) + 1 + k;
+ bits[0] = 32*i - hi0bits(z);
+ }
+ return new BigInteger(dbl_bits);
+ }
+
+ static String JS_dtobasestr(int base, double d)
+ {
+ if (!(2 <= base && base <= 36))
+ throw new IllegalArgumentException("Bad base: "+base);
+
+ /* Check for Infinity and NaN */
+ if (Double.isNaN(d)) {
+ return "NaN";
+ } else if (Double.isInfinite(d)) {
+ return (d > 0.0) ? "Infinity" : "-Infinity";
+ } else if (d == 0) {
+ // ALERT: should it distinguish -0.0 from +0.0 ?
+ return "0";
+ }
+
+ boolean negative;
+ if (d >= 0.0) {
+ negative = false;
+ } else {
+ negative = true;
+ d = -d;
+ }
+
+ /* Get the integer part of d including '-' sign. */
+ String intDigits;
+
+ double dfloor = Math.floor(d);
+ long lfloor = (long)dfloor;
+ if (lfloor == dfloor) {
+ // int part fits long
+ intDigits = Long.toString((negative) ? -lfloor : lfloor, base);
+ } else {
+ // BigInteger should be used
+ long floorBits = Double.doubleToLongBits(dfloor);
+ int exp = (int)(floorBits >> Exp_shiftL) & Exp_mask_shifted;
+ long mantissa;
+ if (exp == 0) {
+ mantissa = (floorBits & Frac_maskL) << 1;
+ } else {
+ mantissa = (floorBits & Frac_maskL) | Exp_msk1L;
+ }
+ if (negative) {
+ mantissa = -mantissa;
+ }
+ exp -= 1075;
+ BigInteger x = BigInteger.valueOf(mantissa);
+ if (exp > 0) {
+ x = x.shiftLeft(exp);
+ } else if (exp < 0) {
+ x = x.shiftRight(-exp);
+ }
+ intDigits = x.toString(base);
+ }
+
+ if (d == dfloor) {
+ // No fraction part
+ return intDigits;
+ } else {
+ /* We have a fraction. */
+
+ char[] buffer; /* The output string */
+ int p; /* index to current position in the buffer */
+ int digit;
+ double df; /* The fractional part of d */
+ BigInteger b;
+
+ buffer = new char[DTOBASESTR_BUFFER_SIZE];
+ p = 0;
+ df = d - dfloor;
+
+ long dBits = Double.doubleToLongBits(d);
+ int word0 = (int)(dBits >> 32);
+ int word1 = (int)(dBits);
+
+ int[] e = new int[1];
+ int[] bbits = new int[1];
+
+ b = d2b(df, e, bbits);
+// JS_ASSERT(e < 0);
+ /* At this point df = b * 2^e. e must be less than zero because 0 < df < 1. */
+
+ int s2 = -(word0 >>> Exp_shift1 & Exp_mask >> Exp_shift1);
+ if (s2 == 0)
+ s2 = -1;
+ s2 += Bias + P;
+ /* 1/2^s2 = (nextDouble(d) - d)/2 */
+// JS_ASSERT(-s2 < e);
+ BigInteger mlo = BigInteger.valueOf(1);
+ BigInteger mhi = mlo;
+ if ((word1 == 0) && ((word0 & Bndry_mask) == 0)
+ && ((word0 & (Exp_mask & Exp_mask << 1)) != 0)) {
+ /* 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 = BigInteger.valueOf(1<<Log2P);
+ }
+
+ b = b.shiftLeft(e[0] + s2);
+ BigInteger s = BigInteger.valueOf(1);
+ s = s.shiftLeft(s2);
+ /* 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. */
+ BigInteger bigBase = BigInteger.valueOf(base);
+
+ boolean done = false;
+ do {
+ b = b.multiply(bigBase);
+ BigInteger[] divResult = b.divideAndRemainder(s);
+ b = divResult[1];
+ digit = (char)(divResult[0].intValue());
+ if (mlo == mhi)
+ mlo = mhi = mlo.multiply(bigBase);
+ else {
+ mlo = mlo.multiply(bigBase);
+ mhi = mhi.multiply(bigBase);
+ }
+
+ /* Do we yet have the shortest string that will round to d? */
+ int j = b.compareTo(mlo);
+ /* j is b/2^s2 compared with mlo/2^s2. */
+ BigInteger delta = s.subtract(mhi);
+ int j1 = (delta.signum() <= 0) ? 1 : b.compareTo(delta);
+ /* j1 is b/2^s2 compared with 1 - mhi/2^s2. */
+ if (j1 == 0 && ((word1 & 1) == 0)) {
+ if (j > 0)
+ digit++;
+ done = true;
+ } else
+ if (j < 0 || (j == 0 && ((word1 & 1) == 0))) {
+ 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 = b.shiftLeft(1);
+ j1 = b.compareTo(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 = true;
+ } else if (j1 > 0) {
+ digit++;
+ done = true;
+ }
+// JS_ASSERT(digit < (uint32)base);
+ buffer[p++] = BASEDIGIT(digit);
+ } while (!done);
+
+ StringBuffer sb = new StringBuffer(intDigits.length() + 1 + p);
+ sb.append(intDigits);
+ sb.append('.');
+ sb.append(buffer, 0, p);
+ return sb.toString();
+ }
+
+ }
+
+ /* 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.
+ */
+
+ static int word0(double d)
+ {
+ long dBits = Double.doubleToLongBits(d);
+ return (int)(dBits >> 32);
+ }
+
+ static double setWord0(double d, int i)
+ {
+ long dBits = Double.doubleToLongBits(d);
+ dBits = ((long)i << 32) | (dBits & 0x0FFFFFFFFL);
+ return Double.longBitsToDouble(dBits);
+ }
+
+ static int word1(double d)
+ {
+ long dBits = Double.doubleToLongBits(d);
+ return (int)(dBits);
+ }
+
+ /* Return b * 5^k. k must be nonnegative. */
+ // XXXX the C version built a cache of these
+ static BigInteger pow5mult(BigInteger b, int k)
+ {
+ return b.multiply(BigInteger.valueOf(5).pow(k));
+ }
+
+ static boolean roundOff(StringBuffer buf)
+ {
+ int i = buf.length();
+ while (i != 0) {
+ --i;
+ char c = buf.charAt(i);
+ if (c != '9') {
+ buf.setCharAt(i, (char)(c + 1));
+ buf.setLength(i + 1);
+ return false;
+ }
+ }
+ buf.setLength(0);
+ return true;
+ }
+
+ /* 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 int
+ JS_dtoa(double d, int mode, boolean biasUp, int ndigits,
+ boolean[] sign, StringBuffer buf)
+ {
+ /* 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.
+ */
+
+ int b2, b5, i, ieps, ilim, ilim0, ilim1,
+ j, j1, k, k0, m2, m5, s2, s5;
+ char dig;
+ long L;
+ long x;
+ BigInteger b, b1, delta, mlo, mhi, S;
+ int[] be = new int[1];
+ int[] bbits = new int[1];
+ double d2, ds, eps;
+ boolean spec_case, denorm, k_check, try_quick, leftright;
+
+ if ((word0(d) & Sign_bit) != 0) {
+ /* set sign for everything, including 0's and NaNs */
+ sign[0] = true;
+ // word0(d) &= ~Sign_bit; /* clear sign bit */
+ d = setWord0(d, word0(d) & ~Sign_bit);
+ }
+ else
+ sign[0] = false;
+
+ if ((word0(d) & Exp_mask) == Exp_mask) {
+ /* Infinity or NaN */
+ buf.append(((word1(d) == 0) && ((word0(d) & Frac_mask) == 0)) ? "Infinity" : "NaN");
+ return 9999;
+ }
+ if (d == 0) {
+// no_digits:
+ buf.setLength(0);
+ buf.append('0'); /* copy "0" to buffer */
+ return 1;
+ }
+
+ b = d2b(d, be, bbits);
+ if ((i = (word0(d) >>> Exp_shift1 & (Exp_mask>>Exp_shift1))) != 0) {
+ d2 = setWord0(d, (word0(d) & Frac_mask1) | 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;
+ denorm = false;
+ }
+ else {
+ /* d is denormalized */
+ i = bbits[0] + be[0] + (Bias + (P-1) - 1);
+ x = (i > 32) ? word0(d) << (64 - i) | word1(d) >>> (i - 32) : word1(d) << (32 - i);
+// d2 = x;
+// word0(d2) -= 31*Exp_msk1; /* adjust exponent */
+ d2 = setWord0(x, word0(x) - 31*Exp_msk1);
+ i -= (Bias + (P-1) - 1) + 1;
+ denorm = true;
+ }
+ /* 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 = (int)ds;
+ if (ds < 0.0 && ds != k)
+ k--; /* want k = floor(ds) */
+ k_check = true;
+ if (k >= 0 && k <= Ten_pmax) {
+ if (d < tens[k])
+ k--;
+ k_check = false;
+ }
+ /* 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[0] - 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 = true;
+ if (mode > 5) {
+ mode -= 4;
+ try_quick = false;
+ }
+ leftright = true;
+ ilim = ilim1 = 0;
+ switch(mode) {
+ case 0:
+ case 1:
+ ilim = ilim1 = -1;
+ i = 18;
+ ndigits = 0;
+ break;
+ case 2:
+ leftright = false;
+ /* no break */
+ case 4:
+ if (ndigits <= 0)
+ ndigits = 1;
+ ilim = ilim1 = i = ndigits;
+ break;
+ case 3:
+ leftright = false;
+ /* 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. */
+
+ boolean fast_failed = false;
+ 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) != 0) {
+ /* prevent overflows */
+ j &= Bletch - 1;
+ d /= bigtens[n_bigtens-1];
+ ieps++;
+ }
+ for(; (j != 0); j >>= 1, i++)
+ if ((j & 1) != 0) {
+ ieps++;
+ ds *= bigtens[i];
+ }
+ d /= ds;
+ }
+ else if ((j1 = -k) != 0) {
+ d *= tens[j1 & 0xf];
+ for(j = j1 >> 4; (j != 0); j >>= 1, i++)
+ if ((j & 1) != 0) {
+ ieps++;
+ d *= bigtens[i];
+ }
+ }
+ /* Check that k was computed correctly. */
+ if (k_check && d < 1.0 && ilim > 0) {
+ if (ilim1 <= 0)
+ fast_failed = true;
+ else {
+ ilim = ilim1;
+ k--;
+ d *= 10.;
+ ieps++;
+ }
+ }
+ /* eps bounds the cumulative error. */
+// eps = ieps*d + 7.0;
+// word0(eps) -= (P-1)*Exp_msk1;
+ eps = ieps*d + 7.0;
+ eps = setWord0(eps, word0(eps) - (P-1)*Exp_msk1);
+ if (ilim == 0) {
+ S = mhi = null;
+ d -= 5.0;
+ if (d > eps) {
+ buf.append('1');
+ k++;
+ return k + 1;
+ }
+ if (d < -eps) {
+ buf.setLength(0);
+ buf.append('0'); /* copy "0" to buffer */
+ return 1;
+ }
+ fast_failed = true;
+ }
+ if (!fast_failed) {
+ fast_failed = true;
+ 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;
+ buf.append((char)('0' + L));
+ if (d < eps) {
+ return k + 1;
+ }
+ if (1.0 - d < eps) {
+// goto bump_up;
+ char lastCh;
+ while (true) {
+ lastCh = buf.charAt(buf.length() - 1);
+ buf.setLength(buf.length() - 1);
+ if (lastCh != '9') break;
+ if (buf.length() == 0) {
+ k++;
+ lastCh = '0';
+ break;
+ }
+ }
+ buf.append((char)(lastCh + 1));
+ return k + 1;
+ }
+ if (++i >= ilim)
+ break;
+ eps *= 10.0;
+ d *= 10.0;
+ }
+ }
+ else {
+ /* Generate ilim digits, then fix them up. */
+ eps *= tens[ilim-1];
+ for(i = 1;; i++, d *= 10.0) {
+ L = (long)d;
+ d -= L;
+ buf.append((char)('0' + L));
+ if (i == ilim) {
+ if (d > 0.5 + eps) {
+// goto bump_up;
+ char lastCh;
+ while (true) {
+ lastCh = buf.charAt(buf.length() - 1);
+ buf.setLength(buf.length() - 1);
+ if (lastCh != '9') break;
+ if (buf.length() == 0) {
+ k++;
+ lastCh = '0';
+ break;
+ }
+ }
+ buf.append((char)(lastCh + 1));
+ return k + 1;
+ }
+ else
+ if (d < 0.5 - eps) {
+ stripTrailingZeroes(buf);
+// while(*--s == '0') ;
+// s++;
+ return k + 1;
+ }
+ break;
+ }
+ }
+ }
+ }
+ if (fast_failed) {
+ buf.setLength(0);
+ d = d2;
+ k = k0;
+ ilim = ilim0;
+ }
+ }
+
+ /* Do we have a "small" integer? */
+
+ if (be[0] >= 0 && k <= Int_max) {
+ /* Yes. */
+ ds = tens[k];
+ if (ndigits < 0 && ilim <= 0) {
+ S = mhi = null;
+ if (ilim < 0 || d < 5*ds || (!biasUp && d == 5*ds)) {
+ buf.setLength(0);
+ buf.append('0'); /* copy "0" to buffer */
+ return 1;
+ }
+ buf.append('1');
+ k++;
+ return k + 1;
+ }
+ for(i = 1;; i++) {
+ L = (long) (d / ds);
+ d -= L*ds;
+ buf.append((char)('0' + L));
+ if (i == ilim) {
+ d += d;
+ if ((d > ds) || (d == ds && (((L & 1) != 0) || biasUp))) {
+// bump_up:
+// while(*--s == '9')
+// if (s == buf) {
+// k++;
+// *s = '0';
+// break;
+// }
+// ++*s++;
+ char lastCh;
+ while (true) {
+ lastCh = buf.charAt(buf.length() - 1);
+ buf.setLength(buf.length() - 1);
+ if (lastCh != '9') break;
+ if (buf.length() == 0) {
+ k++;
+ lastCh = '0';
+ break;
+ }
+ }
+ buf.append((char)(lastCh + 1));
+ }
+ break;
+ }
+ d *= 10.0;
+ if (d == 0)
+ break;
+ }
+ return k + 1;
+ }
+
+ m2 = b2;
+ m5 = b5;
+ mhi = mlo = null;
+ if (leftright) {
+ if (mode < 2) {
+ i = (denorm) ? be[0] + (Bias + (P-1) - 1 + 1) : 1 + P - bbits[0];
+ /* 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 = BigInteger.valueOf(1);
+ /* (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);
+ b1 = mhi.multiply(b);
+ b = b1;
+ }
+ if ((j = b5 - m5) != 0)
+ b = pow5mult(b, j);
+ }
+ else
+ b = pow5mult(b, b5);
+ }
+ /* 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 = BigInteger.valueOf(1);
+ if (s5 > 0)
+ S = pow5mult(S, s5);
+ /* 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 = false;
+ if (mode < 2) {
+ if ( (word1(d) == 0) && ((word0(d) & Bndry_mask) == 0)
+ && ((word0(d) & (Exp_mask & Exp_mask << 1)) != 0)
+ ) {
+ /* 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 = true;
+ }
+ }
+
+ /* 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.
+ */
+ byte [] S_bytes = S.toByteArray();
+ int S_hiWord = 0;
+ for (int idx = 0; idx < 4; idx++) {
+ S_hiWord = (S_hiWord << 8);
+ if (idx < S_bytes.length)
+ S_hiWord |= (S_bytes[idx] & 0xFF);
+ }
+ if ((i = (((s5 != 0) ? 32 - hi0bits(S_hiWord) : 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 = b.shiftLeft(b2);
+ if (s2 > 0)
+ S = S.shiftLeft(s2);
+ /* Now we have d/10^k = b/S and
+ (mhi * 2^m2) / S = maximum acceptable error, divided by 10^k. */
+ if (k_check) {
+ if (b.compareTo(S) < 0) {
+ k--;
+ b = b.multiply(BigInteger.valueOf(10)); /* we botched the k estimate */
+ if (leftright)
+ mhi = mhi.multiply(BigInteger.valueOf(10));
+ 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 )
+ || ((i = b.compareTo(S = S.multiply(BigInteger.valueOf(5)))) < 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; */
+ buf.setLength(0);
+ buf.append('0'); /* copy "0" to buffer */
+ return 1;
+// goto no_digits;
+ }
+// one_digit:
+ buf.append('1');
+ k++;
+ return k + 1;
+ }
+ if (leftright) {
+ if (m2 > 0)
+ mhi = mhi.shiftLeft(m2);
+
+ /* Compute mlo -- check for special case
+ * that d is a normalized power of 2.
+ */
+
+ mlo = mhi;
+ if (spec_case) {
+ mhi = mlo;
+ mhi = mhi.shiftLeft(Log2P);
+ }
+ /* 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++) {
+ BigInteger[] divResult = b.divideAndRemainder(S);
+ b = divResult[1];
+ dig = (char)(divResult[0].intValue() + '0');
+ /* Do we yet have the shortest decimal string
+ * that will round to d?
+ */
+ j = b.compareTo(mlo);
+ /* j is b/S compared with mlo/S. */
+ delta = S.subtract(mhi);
+ j1 = (delta.signum() <= 0) ? 1 : b.compareTo(delta);
+ /* j1 is b/S compared with 1 - mhi/S. */
+ if ((j1 == 0) && (mode == 0) && ((word1(d) & 1) == 0)) {
+ if (dig == '9') {
+ buf.append('9');
+ if (roundOff(buf)) {
+ k++;
+ buf.append('1');
+ }
+ return k + 1;
+// goto round_9_up;
+ }
+ if (j > 0)
+ dig++;
+ buf.append(dig);
+ return k + 1;
+ }
+ if ((j < 0)
+ || ((j == 0)
+ && (mode == 0)
+ && ((word1(d) & 1) == 0)
+ )) {
+ 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 = b.shiftLeft(1);
+ j1 = b.compareTo(S);
+ if (((j1 > 0) || (j1 == 0 && (((dig & 1) == 1) || biasUp)))
+ && (dig++ == '9')) {
+ buf.append('9');
+ if (roundOff(buf)) {
+ k++;
+ buf.append('1');
+ }
+ return k + 1;
+// goto round_9_up;
+ }
+ }
+ buf.append(dig);
+ return k + 1;
+ }
+ if (j1 > 0) {
+ if (dig == '9') { /* possible if i == 1 */
+// round_9_up:
+// *s++ = '9';
+// goto roundoff;
+ buf.append('9');
+ if (roundOff(buf)) {
+ k++;
+ buf.append('1');
+ }
+ return k + 1;
+ }
+ buf.append((char)(dig + 1));
+ return k + 1;
+ }
+ buf.append(dig);
+ if (i == ilim)
+ break;
+ b = b.multiply(BigInteger.valueOf(10));
+ if (mlo == mhi)
+ mlo = mhi = mhi.multiply(BigInteger.valueOf(10));
+ else {
+ mlo = mlo.multiply(BigInteger.valueOf(10));
+ mhi = mhi.multiply(BigInteger.valueOf(10));
+ }
+ }
+ }
+ else
+ for(i = 1;; i++) {
+// (char)(dig = quorem(b,S) + '0');
+ BigInteger[] divResult = b.divideAndRemainder(S);
+ b = divResult[1];
+ dig = (char)(divResult[0].intValue() + '0');
+ buf.append(dig);
+ if (i >= ilim)
+ break;
+ b = b.multiply(BigInteger.valueOf(10));
+ }
+
+ /* Round off last digit */
+
+ b = b.shiftLeft(1);
+ j = b.compareTo(S);
+ if ((j > 0) || (j == 0 && (((dig & 1) == 1) || biasUp))) {
+// roundoff:
+// while(*--s == '9')
+// if (s == buf) {
+// k++;
+// *s++ = '1';
+// goto ret;
+// }
+// ++*s++;
+ if (roundOff(buf)) {
+ k++;
+ buf.append('1');
+ return k + 1;
+ }
+ }
+ else {
+ stripTrailingZeroes(buf);
+// 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);
+ return k + 1;
+ }
+
+ private static void
+ stripTrailingZeroes(StringBuffer buf)
+ {
+// while(*--s == '0') ;
+// s++;
+ int bl = buf.length();
+ while(bl-->0 && buf.charAt(bl) == '0') {
+ // empty
+ }
+ buf.setLength(bl + 1);
+ }
+
+ /* Mapping of JSDToStrMode -> JS_dtoa mode */
+ private static final int dtoaModes[] = {
+ 0, /* DTOSTR_STANDARD */
+ 0, /* DTOSTR_STANDARD_EXPONENTIAL, */
+ 3, /* DTOSTR_FIXED, */
+ 2, /* DTOSTR_EXPONENTIAL, */
+ 2}; /* DTOSTR_PRECISION */
+
+ static void
+ JS_dtostr(StringBuffer buffer, int mode, int precision, double d)
+ {
+ int decPt; /* Position of decimal point relative to first digit returned by JS_dtoa */
+ boolean[] sign = new boolean[1]; /* true if the sign bit was set in d */
+ int nDigits; /* Number of significand digits returned by JS_dtoa */
+
+// 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. */
+
+ decPt = JS_dtoa(d, dtoaModes[mode], mode >= DTOSTR_FIXED, precision, sign, buffer);
+ nDigits = buffer.length();
+
+ /* If Infinity, -Infinity, or NaN, return the string regardless of the mode. */
+ if (decPt != 9999) {
+ boolean exponentialNotation = false;
+ int minNDigits = 0; /* Minimum number of significand digits required by mode and precision */
+ int p;
+
+ switch (mode) {
+ case DTOSTR_STANDARD:
+ if (decPt < -5 || decPt > 21)
+ exponentialNotation = 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 = true;
+ break;
+
+ case DTOSTR_PRECISION:
+// JS_ASSERT(precision > 0);
+ minNDigits = precision;
+ if (decPt < -5 || decPt > precision)
+ exponentialNotation = true;
+ break;
+ }
+
+ /* If the number has fewer than minNDigits, pad it with zeros at the end */
+ if (nDigits < minNDigits) {
+ p = minNDigits;
+ nDigits = minNDigits;
+ do {
+ buffer.append('0');
+ } while (buffer.length() != p);
+ }
+
+ if (exponentialNotation) {
+ /* Insert a decimal point if more than one significand digit */
+ if (nDigits != 1) {
+ buffer.insert(1, '.');
+ }
+ buffer.append('e');
+ if ((decPt - 1) >= 0)
+ buffer.append('+');
+ buffer.append(decPt - 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 */
+ buffer.insert(decPt, '.');
+ } else {
+ /* 0 . 00...00dd...dd */
+ for (int i = 0; i < 1 - decPt; i++)
+ buffer.insert(0, '0');
+ buffer.insert(1, '.');
+ }
+ }
+ }
+
+ /* If negative and neither -0.0 nor NaN, output a leading '-'. */
+ if (sign[0] &&
+ !(word0(d) == Sign_bit && word1(d) == 0) &&
+ !((word0(d) & Exp_mask) == Exp_mask &&
+ ((word1(d) != 0) || ((word0(d) & Frac_mask) != 0)))) {
+ buffer.insert(0, '-');
+ }
+ }
+
+}
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-18 12:21:49 +0000