The Tor Browser: build/stlport/src/num_get_float.cpp@b8a032363ba2 (annotated)

build/stlport/src/num_get_float.cpp@b8a032363ba2 (annotated)

build/stlport/src/num_get_float.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /*
  * Copyright (c) 1999
  * Silicon Graphics Computer Systems, Inc.
  *
  * Copyright (c) 1999
  * Boris Fomitchev
  *
  * This material is provided "as is", with absolutely no warranty expressed
  * or implied. Any use is at your own risk.
  *
  * Permission to use or copy this software for any purpose is hereby granted
  * without fee, provided the above notices are retained on all copies.
  * Permission to modify the code and to distribute modified code is granted,
  * provided the above notices are retained, and a notice that the code was
  * modified is included with the above copyright notice.
  *
  */
 #include "stlport_prefix.h"
 #include <limits>
 #include <locale>
 #include <istream>
 #if (defined (__GNUC__) && !defined (__sun) && !defined (__hpux)) || \
     defined (__DMC__)
 #  include <stdint.h>
 #endif
 #if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
     defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
 #  if defined (__BORLANDC__)
 typedef unsigned int uint32_t;
 typedef unsigned __int64 uint64_t;
 #  endif
 union _ll {
   uint64_t i64;
   struct {
 #  if defined (_STLP_BIG_ENDIAN)
     uint32_t hi;
     uint32_t lo;
 #  elif defined (_STLP_LITTLE_ENDIAN)
     uint32_t lo;
     uint32_t hi;
 #  else
 #    error Unknown endianess
 #  endif
   } i32;
 };
 #  if defined (__linux__) && !defined (__ANDROID__)
 #    include <ieee754.h>
 #  else
 union ieee854_long_double {
   long double d;
   /* This is the IEEE 854 double-extended-precision format.  */
   struct {
     unsigned int mantissa1:32;
     unsigned int mantissa0:32;
     unsigned int exponent:15;
     unsigned int negative:1;
     unsigned int empty:16;
   } ieee;
 };
 #    define IEEE854_LONG_DOUBLE_BIAS 0x3fff
 #  endif
 #endif
 _STLP_BEGIN_NAMESPACE
 _STLP_MOVE_TO_PRIV_NAMESPACE
 //----------------------------------------------------------------------
 // num_get
 // Helper functions for _M_do_get_float.
 #if !defined (_STLP_NO_WCHAR_T)
 void  _STLP_CALL
 _Initialize_get_float( const ctype<wchar_t>& ct,
                        wchar_t& Plus, wchar_t& Minus,
                        wchar_t& pow_e, wchar_t& pow_E,
                        wchar_t* digits) {
   char ndigits[11] = "0123456789";
   Plus  = ct.widen('+');
   Minus = ct.widen('-');
   pow_e = ct.widen('e');
   pow_E = ct.widen('E');
   ct.widen(ndigits + 0, ndigits + 10, digits);
 }
 #endif /* WCHAR_T */
 /*
  * __string_to_double is just lifted from atof, the difference being
  * that we just use '.' for the decimal point, rather than let it
  * be taken from the current C locale, which of course is not accessible
  * to us.
  */
 #if defined (_STLP_MSVC) || defined (__BORLANDC__) || defined (__ICL)
 typedef unsigned long uint32;
 typedef unsigned __int64 uint64;
 #  define ULL(x) x##Ui64
 #elif defined (__unix) || defined (__MINGW32__) || \
       (defined (__DMC__) && (__LONGLONG)) || defined (__WATCOMC__) || \
       defined (__ANDROID__)
 typedef uint32_t uint32;
 typedef uint64_t uint64;
 #  define ULL(x) x##ULL
 #else
 #  error There should be some unsigned 64-bit integer on the system!
 #endif
 // Multiplication of two 64-bit integers, giving a 128-bit result.
 // Taken from Algorithm M in Knuth section 4.3.1, with the loop
 // hand-unrolled.
 static void _Stl_mult64(const uint64 u, const uint64 v,
                         uint64& high, uint64& low) {
   const uint64 low_mask = ULL(0xffffffff);
   const uint64 u0 = u & low_mask;
   const uint64 u1 = u >> 32;
   const uint64 v0 = v & low_mask;
   const uint64 v1 = v >> 32;
   uint64 t = u0 * v0;
   low = t & low_mask;
   t = u1 * v0 + (t >> 32);
   uint64 w1 = t & low_mask;
   uint64 w2 = t >> 32;
   uint64 x = u0 * v1 + w1;
   low += (x & low_mask) << 32;
   high = u1 * v1 + w2 + (x >> 32);
 }
 #if !defined (__linux__) || defined (__ANDROID__)
 #  define bit11 ULL(0x7ff)
 #  define exponent_mask (bit11 << 52)
 #  if !defined (__GNUC__) || (__GNUC__ != 3) || (__GNUC_MINOR__ != 4) || \
       (!defined (__CYGWIN__) && !defined (__MINGW32__))
 //Generate bad code when compiled with -O2 option.
 inline
 #  endif
 void _Stl_set_exponent(uint64 &val, uint64 exp)
 { val = (val & ~exponent_mask) | ((exp & bit11) << 52); }
 #endif // __linux__
 /* Power of ten fractions for tenscale*/
 /* The constants are factored so that at most two constants
  * and two multiplies are needed. Furthermore, one of the constants
  * is represented exactly - 10**n where 1<= n <= 27.
  */
 static const uint64 _Stl_tenpow[80] = {
 ULL(0xa000000000000000), /* _Stl_tenpow[0]=(10**1)/(2**4) */
 ULL(0xc800000000000000), /* _Stl_tenpow[1]=(10**2)/(2**7) */
 ULL(0xfa00000000000000), /* _Stl_tenpow[2]=(10**3)/(2**10) */
 ULL(0x9c40000000000000), /* _Stl_tenpow[3]=(10**4)/(2**14) */
 ULL(0xc350000000000000), /* _Stl_tenpow[4]=(10**5)/(2**17) */
 ULL(0xf424000000000000), /* _Stl_tenpow[5]=(10**6)/(2**20) */
 ULL(0x9896800000000000), /* _Stl_tenpow[6]=(10**7)/(2**24) */
 ULL(0xbebc200000000000), /* _Stl_tenpow[7]=(10**8)/(2**27) */
 ULL(0xee6b280000000000), /* _Stl_tenpow[8]=(10**9)/(2**30) */
 ULL(0x9502f90000000000), /* _Stl_tenpow[9]=(10**10)/(2**34) */
 ULL(0xba43b74000000000), /* _Stl_tenpow[10]=(10**11)/(2**37) */
 ULL(0xe8d4a51000000000), /* _Stl_tenpow[11]=(10**12)/(2**40) */
 ULL(0x9184e72a00000000), /* _Stl_tenpow[12]=(10**13)/(2**44) */
 ULL(0xb5e620f480000000), /* _Stl_tenpow[13]=(10**14)/(2**47) */
 ULL(0xe35fa931a0000000), /* _Stl_tenpow[14]=(10**15)/(2**50) */
 ULL(0x8e1bc9bf04000000), /* _Stl_tenpow[15]=(10**16)/(2**54) */
 ULL(0xb1a2bc2ec5000000), /* _Stl_tenpow[16]=(10**17)/(2**57) */
 ULL(0xde0b6b3a76400000), /* _Stl_tenpow[17]=(10**18)/(2**60) */
 ULL(0x8ac7230489e80000), /* _Stl_tenpow[18]=(10**19)/(2**64) */
 ULL(0xad78ebc5ac620000), /* _Stl_tenpow[19]=(10**20)/(2**67) */
 ULL(0xd8d726b7177a8000), /* _Stl_tenpow[20]=(10**21)/(2**70) */
 ULL(0x878678326eac9000), /* _Stl_tenpow[21]=(10**22)/(2**74) */
 ULL(0xa968163f0a57b400), /* _Stl_tenpow[22]=(10**23)/(2**77) */
 ULL(0xd3c21bcecceda100), /* _Stl_tenpow[23]=(10**24)/(2**80) */
 ULL(0x84595161401484a0), /* _Stl_tenpow[24]=(10**25)/(2**84) */
 ULL(0xa56fa5b99019a5c8), /* _Stl_tenpow[25]=(10**26)/(2**87) */
 ULL(0xcecb8f27f4200f3a), /* _Stl_tenpow[26]=(10**27)/(2**90) */
 ULL(0xd0cf4b50cfe20766), /* _Stl_tenpow[27]=(10**55)/(2**183) */
 ULL(0xd2d80db02aabd62c), /* _Stl_tenpow[28]=(10**83)/(2**276) */
 ULL(0xd4e5e2cdc1d1ea96), /* _Stl_tenpow[29]=(10**111)/(2**369) */
 ULL(0xd6f8d7509292d603), /* _Stl_tenpow[30]=(10**139)/(2**462) */
 ULL(0xd910f7ff28069da4), /* _Stl_tenpow[31]=(10**167)/(2**555) */
 ULL(0xdb2e51bfe9d0696a), /* _Stl_tenpow[32]=(10**195)/(2**648) */
 ULL(0xdd50f1996b947519), /* _Stl_tenpow[33]=(10**223)/(2**741) */
 ULL(0xdf78e4b2bd342cf7), /* _Stl_tenpow[34]=(10**251)/(2**834) */
 ULL(0xe1a63853bbd26451), /* _Stl_tenpow[35]=(10**279)/(2**927) */
 ULL(0xe3d8f9e563a198e5), /* _Stl_tenpow[36]=(10**307)/(2**1020) */
 // /* _Stl_tenpow[36]=(10**335)/(2**) */
 // /* _Stl_tenpow[36]=(10**335)/(2**) */
 ULL(0xfd87b5f28300ca0e), /* _Stl_tenpow[37]=(10**-28)/(2**-93) */
 ULL(0xfb158592be068d2f), /* _Stl_tenpow[38]=(10**-56)/(2**-186) */
 ULL(0xf8a95fcf88747d94), /* _Stl_tenpow[39]=(10**-84)/(2**-279) */
 ULL(0xf64335bcf065d37d), /* _Stl_tenpow[40]=(10**-112)/(2**-372) */
 ULL(0xf3e2f893dec3f126), /* _Stl_tenpow[41]=(10**-140)/(2**-465) */
 ULL(0xf18899b1bc3f8ca2), /* _Stl_tenpow[42]=(10**-168)/(2**-558) */
 ULL(0xef340a98172aace5), /* _Stl_tenpow[43]=(10**-196)/(2**-651) */
 ULL(0xece53cec4a314ebe), /* _Stl_tenpow[44]=(10**-224)/(2**-744) */
 ULL(0xea9c227723ee8bcb), /* _Stl_tenpow[45]=(10**-252)/(2**-837)     */
 ULL(0xe858ad248f5c22ca), /* _Stl_tenpow[46]=(10**-280)/(2**-930) */
 ULL(0xe61acf033d1a45df), /* _Stl_tenpow[47]=(10**-308)/(2**-1023)    */
 ULL(0xe3e27a444d8d98b8), /* _Stl_tenpow[48]=(10**-336)/(2**-1116) */
 ULL(0xe1afa13afbd14d6e)  /* _Stl_tenpow[49]=(10**-364)/(2**-1209) */
 };
 static const short _Stl_twoexp[80] = {
 ,7,10,14,17,20,24,27,30,34,37,40,44,47,50,54,57,60,64,67,70,74,77,80,84,87,90,
 ,276,369,462,555,648,741,834,927,1020,
 -93,-186,-279,-372,-465,-558,-651,-744,-837,-930,-1023,-1116,-1209
 };
 #define  TEN_1  0           /* offset to 10 **   1 */
 #define  TEN_27   26        /* offset to 10 **  27 */
 #define  TEN_M28  37        /* offset to 10 ** -28 */
 #define  NUM_HI_P 11
 #define  NUM_HI_N 13
 #define _Stl_HIBITULL (ULL(1) << 63)
 static void _Stl_norm_and_round(uint64& p, int& norm, uint64 prodhi, uint64 prodlo) {
   norm = 0;
   if ((prodhi & _Stl_HIBITULL) == 0) {
                                 /* leading bit is a zero
                                  * may have to normalize
                                  */
     if ((prodhi == ~_Stl_HIBITULL) &&
         ((prodlo >> 62) == 0x3)) {  /* normalization followed by round
                                      * would cause carry to create
                                      * extra bit, so don't normalize
                                      */
       p = _Stl_HIBITULL;
       return;
     }
     p = (prodhi << 1) | (prodlo >> 63); /* normalize */
     norm = 1;
     prodlo <<= 1;
   }
   else {
     p = prodhi;
   }
   if ((prodlo & _Stl_HIBITULL) != 0) {     /* first guard bit a one */
     if (((p & 0x1) != 0) ||
         prodlo != _Stl_HIBITULL ) {    /* not borderline for round to even */
       /* round */
       ++p;
       if (p == 0)
         ++p;
     }
   }
 }
 // Convert a 64-bitb fraction * 10^exp to a 64-bit fraction * 2^bexp.
 // p:    64-bit fraction
 // exp:  base-10 exponent
 // bexp: base-2 exponent (output parameter)
 static void _Stl_tenscale(uint64& p, int exp, int& bexp) {
   bexp = 0;
   if ( exp == 0 ) {              /* no scaling needed */
     return;
   }
   int exp_hi = 0, exp_lo = exp; /* exp = exp_hi*32 + exp_lo */
   int tlo = TEN_1, thi;         /* offsets in power of ten table */
   int num_hi;                   /* number of high exponent powers */
   if (exp > 0) {                /* split exponent */
     if (exp_lo > 27) {
       exp_lo++;
       while (exp_lo > 27) {
         exp_hi++;
         exp_lo -= 28;
       }
     }
     thi = TEN_27;
     num_hi = NUM_HI_P;
   } else { // exp < 0
     while (exp_lo < 0) {
       exp_hi++;
       exp_lo += 28;
     }
     thi = TEN_M28;
     num_hi = NUM_HI_N;
   }
   uint64 prodhi, prodlo;        /* 128b product */
   int norm;                     /* number of bits of normalization */
   int hi, lo;                   /* offsets in power of ten table */
   while (exp_hi) {              /* scale */
     hi = (min) (exp_hi, num_hi);    /* only a few large powers of 10 */
     exp_hi -= hi;               /* could iterate in extreme case */
     hi += thi-1;
     _Stl_mult64(p, _Stl_tenpow[hi], prodhi, prodlo);
     _Stl_norm_and_round(p, norm, prodhi, prodlo);
     bexp += _Stl_twoexp[hi] - norm;
   }
   if (exp_lo) {
     lo = tlo + exp_lo -1;
     _Stl_mult64(p, _Stl_tenpow[lo], prodhi, prodlo);
     _Stl_norm_and_round(p, norm, prodhi, prodlo);
     bexp += _Stl_twoexp[lo] - norm;
   }
   return;
 }
 // First argument is a buffer of values from 0 to 9, NOT ascii.
 // Second argument is number of digits in buffer, 1 <= digits <= 17.
 // Third argument is base-10 exponent.
 /* IEEE representation */
 #if !defined (__linux__) || defined (__ANDROID__)
 union _Double_rep {
   uint64 ival;
   double val;
 };
 static double _Stl_atod(char *buffer, ptrdiff_t ndigit, int dexp) {
   typedef numeric_limits<double> limits;
   _Double_rep drep;
   uint64 &value = drep.ival;  /* Value develops as follows:
                                  * 1) decimal digits as an integer
                                  * 2) left adjusted fraction
                                  * 3) right adjusted fraction
                                  * 4) exponent and fraction
                                  */
   uint32 guard;         /* First guard bit */
   uint64 rest;          /* Remaining guard bits */
   int bexp;             /* binary exponent */
   int nzero;            /* number of non-zero bits */
   int sexp;             /* scaling exponent */
   char *bufferend;              /* pointer to char after last digit */
   /* Convert the decimal digits to a binary integer. */
   bufferend = buffer + ndigit;
   value = 0;
   while (buffer < bufferend) {
     value *= 10;
     value += *buffer++;
   }
   /* Check for zero and treat it as a special case */
   if (value == 0) {
     return 0.0;
   }
   /* Normalize value */
   bexp = 64;                    /* convert from 64b int to fraction */
   /* Count number of non-zeroes in value */
   nzero = 0;
   if ((value >> 32) != 0) { nzero  = 32; }    //*TY 03/25/2000 - added explicit comparison to zero to avoid uint64 to bool conversion operator
   if ((value >> (16 + nzero)) != 0) { nzero += 16; }
   if ((value >> ( 8 + nzero)) != 0) { nzero +=  8; }
   if ((value >> ( 4 + nzero)) != 0) { nzero +=  4; }
   if ((value >> ( 2 + nzero)) != 0) { nzero +=  2; }
   if ((value >> ( 1 + nzero)) != 0) { nzero +=  1; }
   if ((value >> (     nzero)) != 0) { nzero +=  1; }
   /* Normalize */
   value <<= /*(uint64)*/ (64 - nzero);    //*TY 03/25/2000 - removed extraneous cast to uint64
   bexp -= 64 - nzero;
   /* At this point we have a 64b fraction and a binary exponent
    * but have yet to incorporate the decimal exponent.
    */
   /* multiply by 10^dexp */
   _Stl_tenscale(value, dexp, sexp);
   bexp += sexp;
   if (bexp <= -1022) {          /* HI denorm or underflow */
     bexp += 1022;
     if (bexp < -53) {          /* guaranteed underflow */
       value = 0;
     }
     else {                      /* denorm or possible underflow */
       int lead0 = 12 - bexp;          /* 12 sign and exponent bits */
       /* we must special case right shifts of more than 63 */
       if (lead0 > 64) {
         rest = value;
         guard = 0;
         value = 0;
       }
       else if (lead0 == 64) {
         rest = value & ((ULL(1)<< 63)-1);
         guard = (uint32) ((value>> 63) & 1 );
         value = 0;
       }
       else {
         rest = value & (((ULL(1) << lead0)-1)-1);
         guard = (uint32) (((value>> lead0)-1) & 1);
         value >>= /*(uint64)*/ lead0; /* exponent is zero */
       }
       /* Round */
       if (guard && ((value & 1) || rest) ) {
         ++value;
         if (value == (ULL(1) << (limits::digits - 1))) { /* carry created normal number */
           value = 0;
           _Stl_set_exponent(value, 1);
         }
       }
     }
   }
   else {                        /* not zero or denorm */
     /* Round to 53 bits */
     rest = value & ((1 << 10) - 1);
     value >>= 10;
     guard = (uint32) value & 1;
     value >>= 1;
     /*  value&1 guard   rest    Action
      *
      *  dc      0       dc      none
      *  1       1       dc      round
      *  0       1       0       none
      *  0       1       !=0     round
      */
     if (guard) {
       if (((value&1)!=0) || (rest!=0)) {
         ++value;                        /* round */
         if ((value >> 53) != 0) {       /* carry all the way across */
           value >>= 1;          /* renormalize */
           ++bexp;
         }
       }
     }
     /*
      * Check for overflow
      * IEEE Double Precision Format
      * (From Table 7-8 of Kane and Heinrich)
      *
      * Fraction bits               52
      * Emax                     +1023
      * Emin                     -1022
      * Exponent bias            +1023
      * Exponent bits               11
      * Integer bit             hidden
      * Total width in bits         64
      */
     if (bexp > limits::max_exponent) {          /* overflow */
       return limits::infinity();
     }
     else {                      /* value is normal */
       value &= ~(ULL(1) << (limits::digits - 1));   /* hide hidden bit */
       _Stl_set_exponent(value, bexp + 1022); /* add bias */
     }
   }
   _STLP_STATIC_ASSERT(sizeof(uint64) >= sizeof(double))
   return drep.val;
 }
 #endif
 #if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
     defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
 template <class D, class IEEE, int M, int BIAS>
 D _Stl_atodT(char *buffer, ptrdiff_t ndigit, int dexp)
 {
   typedef numeric_limits<D> limits;
   /* Convert the decimal digits to a binary integer. */
   char *bufferend = buffer + ndigit; /* pointer to char after last digit */
   _ll vv;
   vv.i64 = 0L;
   while ( buffer < bufferend ) {
     vv.i64 *= 10;
     vv.i64 += *buffer++;
   }
   if ( vv.i64 == ULL(0) ) { /* Check for zero and treat it as a special case */
     return D(0.0);
   }
   /* Normalize value */
   int bexp = 64; /* convert from 64b int to fraction */
   /* Count number of non-zeroes in value */
   int nzero = 0;
   if ((vv.i64 >> 32) != 0) { nzero = 32; }
   if ((vv.i64 >> (16 + nzero)) != 0) { nzero += 16; }
   if ((vv.i64 >> ( 8 + nzero)) != 0) { nzero +=  8; }
   if ((vv.i64 >> ( 4 + nzero)) != 0) { nzero +=  4; }
   if ((vv.i64 >> ( 2 + nzero)) != 0) { nzero +=  2; }
   if ((vv.i64 >> ( 1 + nzero)) != 0) { nzero +=  1; }
   if ((vv.i64 >> (     nzero)) != 0) { nzero +=  1; }
   /* Normalize */
   nzero = 64 - nzero;
   vv.i64 <<= nzero;    // * TY 03/25/2000 - removed extraneous cast to uint64
   bexp -= nzero;
   /* At this point we have a 64b fraction and a binary exponent
    * but have yet to incorporate the decimal exponent.
    */
   /* multiply by 10^dexp */
   int sexp;
   _Stl_tenscale(vv.i64, dexp, sexp);
   bexp += sexp;
   if ( bexp >= limits::min_exponent ) { /* not zero or denorm */
     if ( limits::digits < 64 ) {
       /* Round to (64 - M + 1) bits */
       uint64_t rest = vv.i64 & ((~ULL(0) / ULL(2)) >> (limits::digits - 1));
       vv.i64 >>= M - 2;
       uint32_t guard = (uint32) vv.i64 & 1;
       vv.i64 >>= 1;
       /*  value&1 guard   rest    Action
        *
        *  dc      0       dc      none
        *  1       1       dc      round
        *  0       1       0       none
        *  0       1       !=0     round
        */
       if (guard) {
         if ( ((vv.i64 & 1) != 0) || (rest != 0) ) {
           vv.i64++;       /* round */
           if ( (vv.i64 >> (limits::digits < 64 ? limits::digits : 0)) != 0 ) { /* carry all the way across */
             vv.i64 >>= 1; /* renormalize */
             ++bexp;
           }
         }
       }
       vv.i64 &= ~(ULL(1) << (limits::digits - 1)); /* hide hidden bit */
     }
     /*
      * Check for overflow
      * IEEE Double Precision Format
      * (From Table 7-8 of Kane and Heinrich)
      *
      * Fraction bits               52
      * Emax                     +1023
      * Emin                     -1022
      * Exponent bias            +1023
      * Exponent bits               11
      * Integer bit             hidden
      * Total width in bits         64
      */
     if (bexp > limits::max_exponent) { /* overflow */
       return limits::infinity();
     }
     /* value is normal */
     IEEE v;
     v.ieee.mantissa0 = vv.i32.hi;
     v.ieee.mantissa1 = vv.i32.lo;
     v.ieee.negative = 0;
     v.ieee.exponent = bexp + BIAS - 1;
     return v.d;
   }
   /* HI denorm or underflow */
   bexp += BIAS - 1;
   if (bexp < -limits::digits) { /* guaranteed underflow */
     vv.i64 = 0;
   } else {  /* denorm or possible underflow */
     /*
      * Problem point for long double: looks like this code reflect shareing of mantissa
      * and exponent in 64b int; not so for long double
      */
     int lead0 = M - bexp; /* M = 12 sign and exponent bits */
     uint64_t rest;
     uint32_t guard;
     /* we must special case right shifts of more than 63 */
     if (lead0 > 64) {
       rest = vv.i64;
       guard = 0;
       vv.i64 = 0;
     } else if (lead0 == 64) {
       rest = vv.i64 & ((ULL(1) << 63)-1);
       guard = (uint32) ((vv.i64 >> 63) & 1 );
       vv.i64 = 0;
     } else {
       rest = vv.i64 & (((ULL(1) << lead0)-1)-1);
       guard = (uint32) (((vv.i64 >> lead0)-1) & 1);
       vv.i64 >>= /*(uint64)*/ lead0; /* exponent is zero */
     }
     /* Round */
     if (guard && ( (vv.i64 & 1) || rest)) {
       vv.i64++;
       if (vv.i64 == (ULL(1) << (limits::digits - 1))) { /* carry created normal number */
         IEEE v;
         v.ieee.mantissa0 = 0;
         v.ieee.mantissa1 = 0;
         v.ieee.negative = 0;
         v.ieee.exponent = 1;
         return v.d;
       }
     }
   }
   IEEE v;
   v.ieee.mantissa0 = vv.i32.hi;
   v.ieee.mantissa1 = vv.i32.lo;
   v.ieee.negative = 0;
   v.ieee.exponent = 0;
   return v.d;
 }
 #endif // __linux__
 #if !defined (__linux__) || defined (__ANDROID__)
 static double _Stl_string_to_double(const char *s) {
   typedef numeric_limits<double> limits;
   const int max_digits = limits::digits10 + 2;
   unsigned c;
   unsigned Negate, decimal_point;
   char *d;
   int exp;
   int dpchar;
   char digits[max_digits];
   c = *s++;
   /* process sign */
   Negate = 0;
   if (c == '+') {
     c = *s++;
   } else if (c == '-') {
     Negate = 1;
     c = *s++;
   }
   d = digits;
   dpchar = '.' - '0';
   decimal_point = 0;
   exp = 0;
   for (;;) {
     c -= '0';
     if (c < 10) {
       if (d == digits + max_digits) {
         /* ignore more than max_digits digits, but adjust exponent */
         exp += (decimal_point ^ 1);
       } else {
         if (c == 0 && d == digits) {
           /* ignore leading zeros */
         } else {
           *d++ = (char) c;
         }
         exp -= decimal_point;
       }
     } else if (c == (unsigned int) dpchar && !decimal_point) { /* INTERNATIONAL */
       decimal_point = 1;
     } else {
       break;
     }
     c = *s++;
   }
   /* strtod cant return until it finds the end of the exponent */
   if (d == digits) {
     return 0.0;
   }
   if (c == 'e' - '0' || c == 'E' - '0') {
     register unsigned negate_exp = 0;
     register int e = 0;
     c = *s++;
     if (c == '+' || c == ' ') {
       c = *s++;
     } else if (c == '-') {
       negate_exp = 1;
       c = *s++;
     }
     if (c -= '0', c < 10) {
       do {
         e = e * 10 + (int)c;
         c = *s++;
       } while (c -= '0', c < 10);
       if (negate_exp) {
         e = -e;
       }
       exp += e;
     }
   }
   double x;
   ptrdiff_t n = d - digits;
   if ((exp + n - 1) < limits::min_exponent10) {
     x = 0;
   }
   else if ((exp + n - 1) > limits::max_exponent10) {
     x = limits::infinity();
   }
   else {
     /* Let _Stl_atod diagnose under- and over-flows.
      * If the input was == 0.0, we have already returned,
      * so retval of +-Inf signals OVERFLOW, 0.0 UNDERFLOW */
     x = _Stl_atod(digits, n, exp);
   }
   if (Negate) {
     x = -x;
   }
   return x;
 }
 #endif
 #if defined (__linux__) || defined (__MINGW32__) || defined (__CYGWIN__) || \
     defined (__BORLANDC__) || defined (__DMC__) || defined (__HP_aCC)
 template <class D, class IEEE, int M, int BIAS>
 D _Stl_string_to_doubleT(const char *s)
 {
   typedef numeric_limits<D> limits;
   const int max_digits = limits::digits10; /* + 2 17 */;
   unsigned c;
   unsigned decimal_point;
   char *d;
   int exp;
   D x;
   int dpchar;
   char digits[max_digits];
   c = *s++;
   /* process sign */
   bool Negate = false;
   if (c == '+') {
     c = *s++;
   } else if (c == '-') {
     Negate = true;
     c = *s++;
   }
   d = digits;
   dpchar = '.' - '0';
   decimal_point = 0;
   exp = 0;
   for (;;) {
     c -= '0';
     if (c < 10) {
       if (d == digits + max_digits) {
         /* ignore more than max_digits digits, but adjust exponent */
         exp += (decimal_point ^ 1);
       } else {
         if (c == 0 && d == digits) {
           /* ignore leading zeros */
         } else {
           *d++ = (char) c;
         }
         exp -= decimal_point;
       }
     } else if (c == (unsigned int) dpchar && !decimal_point) {    /* INTERNATIONAL */
       decimal_point = 1;
     } else {
       break;
     }
     c = *s++;
   }
   /* strtod cant return until it finds the end of the exponent */
   if (d == digits) {
     return D(0.0);
   }
   if (c == 'e'-'0' || c == 'E'-'0') {
     bool negate_exp = false;
     register int e = 0;
     c = *s++;
     if (c == '+' || c == ' ') {
       c = *s++;
     } else if (c == '-') {
       negate_exp = true;
       c = *s++;
     }
     if (c -= '0', c < 10) {
       do {
         e = e * 10 + (int)c;
         c = *s++;
       } while (c -= '0', c < 10);
       if (negate_exp) {
         e = -e;
       }
       exp += e;
     }
   }
   ptrdiff_t n = d - digits;
   if ((exp + n - 1) < limits::min_exponent10) {
     return D(0.0); // +0.0 is the same as -0.0
   } else if ((exp + n - 1) > limits::max_exponent10 ) {
     // not good, because of x = -x below; this may lead to portability problems
     x = limits::infinity();
   } else {
     /* let _Stl_atod diagnose under- and over-flows */
     /* if the input was == 0.0, we have already returned,
        so retval of +-Inf signals OVERFLOW, 0.0 UNDERFLOW
     */
     x = _Stl_atodT<D,IEEE,M,BIAS>(digits, n, exp);
   }
   return Negate ? -x : x;
 }
 #endif // __linux__
 void _STLP_CALL
 __string_to_float(const __iostring& v, float& val)
 {
 #if !defined (__linux__) || defined (__ANDROID__)
   val = (float)_Stl_string_to_double(v.c_str());
 #else
   val = (float)_Stl_string_to_doubleT<double,ieee754_double,12,IEEE754_DOUBLE_BIAS>(v.c_str());
 #endif
 }
 void _STLP_CALL
 __string_to_float(const __iostring& v, double& val)
 {
 #if !defined (__linux__) || defined (__ANDROID__)
   val = _Stl_string_to_double(v.c_str());
 #else
   val = _Stl_string_to_doubleT<double,ieee754_double,12,IEEE754_DOUBLE_BIAS>(v.c_str());
 #endif
 }
 #if !defined (_STLP_NO_LONG_DOUBLE)
 void _STLP_CALL
 __string_to_float(const __iostring& v, long double& val) {
 #if !defined (__linux__) && !defined (__MINGW32__) && !defined (__CYGWIN__) && \
     !defined (__BORLANDC__) && !defined (__DMC__) && !defined (__HP_aCC)
   //The following function is valid only if long double is an alias for double.
   _STLP_STATIC_ASSERT( sizeof(long double) <= sizeof(double) )
   val = _Stl_string_to_double(v.c_str());
 #else
   val = _Stl_string_to_doubleT<long double,ieee854_long_double,16,IEEE854_LONG_DOUBLE_BIAS>(v.c_str());
 #endif
 }
 #endif
 _STLP_MOVE_TO_STD_NAMESPACE
 _STLP_END_NAMESPACE
 // Local Variables:
 // mode:C++
 // End:

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