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- /****************************************************************
- *
- * 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.
- *
- ***************************************************************/
- /* Please send bug reports to David M. Gay (dmg at acm dot org,
- * with " at " changed at "@" and " dot " changed to "."). */
- /* 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-, VAX-, and IBM-arithmetic machines.
- *
- * This strtod returns a nearest machine number to the input decimal
- * string (or sets errno to ERANGE). 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, IBM, or VAX 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 IBM for IBM mainframe-style floating-point arithmetic.
- * #define VAX for VAX-style floating-point arithmetic (D_floating).
- * #define No_leftright to omit left-right logic in fast floating-point
- * computation of dtoa. This will cause dtoa modes 4 and 5 to be
- * treated the same as modes 2 and 3 for some inputs.
- * #define Honor_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
- * and strtod and dtoa should round accordingly. Unless Trust_FLT_ROUNDS
- * is also #defined, fegetround() will be queried for the rounding mode.
- * Note that both FLT_ROUNDS and fegetround() are specified by the C99
- * standard (and are specified to be consistent, with fesetround()
- * affecting the value of FLT_ROUNDS), but that some (Linux) systems
- * do not work correctly in this regard, so using fegetround() is more
- * portable than using FLT_ROUNDS directly.
- * #define Check_FLT_ROUNDS if FLT_ROUNDS can assume the values 2 or 3
- * and Honor_FLT_ROUNDS is not #defined.
- * #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 and arithmetic
- * that rounds toward +Infinity.
- * #define ROUND_BIASED_without_Round_Up for IEEE-format with biased
- * rounding when the underlying floating-point arithmetic uses
- * unbiased rounding. This prevent using ordinary floating-point
- * arithmetic when the result could be computed with one rounding error.
- * #define Inaccurate_Divide for IEEE-format with correctly rounded
- * products but inaccurate quotients, e.g., for Intel i860.
- * #define NO_LONG_LONG on machines that do not have a "long long"
- * integer type (of >= 64 bits). On such machines, you can
- * #define Just_16 to store 16 bits per 32-bit Long when doing
- * high-precision integer arithmetic. Whether this speeds things
- * up or slows things down depends on the machine and the number
- * being converted. 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 KR_headers for old-style C function headers.
- * #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. Similarly, if you
- * want something other than the system's free() to be called to
- * recycle memory acquired from MALLOC, #define FREE to be the
- * name of the alternate routine. (FREE or free is only called in
- * pathological cases, e.g., in a dtoa call after a dtoa return in
- * mode 3 with thousands of digits requested.)
- * #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: 2304 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. The longest string dtoa can return is about 751 bytes
- * long. For conversions by strtod of strings of 800 digits and
- * all dtoa conversions in single-threaded executions with 8-byte
- * pointers, PRIVATE_MEM >= 7400 appears to suffice; with 4-byte
- * pointers, PRIVATE_MEM >= 7112 appears adequate.
- * #define NO_INFNAN_CHECK if you do not wish to have INFNAN_CHECK
- * #defined automatically on IEEE systems. On such systems,
- * when INFNAN_CHECK is #defined, strtod checks
- * 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.)
- * When INFNAN_CHECK is #defined and No_Hex_NaN is not #defined,
- * strtod also accepts (case insensitively) strings of the form
- * NaN(x), where x is a string of hexadecimal digits and spaces;
- * if there is only one string of hexadecimal digits, it is taken
- * for the 52 fraction bits of the resulting NaN; if there are two
- * or more strings of hex digits, the first is for the high 20 bits,
- * the second and subsequent for the low 32 bits, with intervening
- * white space ignored; but if this results in none of the 52
- * fraction bits being on (an IEEE Infinity symbol), then NAN_WORD0
- * and NAN_WORD1 are used instead.
- * #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(n) and freed
- * by FREE_DTOA_LOCK(n) for n = 0 or 1. (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.
- * If you #define NO_IEEE_Scale on a machine that uses IEEE-format
- * floating-point numbers and flushes underflows to zero rather
- * than implementing gradual underflow, then you must also #define
- * Sudden_Underflow.
- * #define USE_LOCALE to use the current locale's decimal_point value.
- * #define SET_INEXACT if IEEE arithmetic is being used and extra
- * computation should be done to set the inexact flag when the
- * result is inexact and avoid setting inexact when the result
- * is exact. In this case, dtoa.c must be compiled in
- * an environment, perhaps provided by #include "dtoa.c" in a
- * suitable wrapper, that defines two functions,
- * int get_inexact(void);
- * void clear_inexact(void);
- * such that get_inexact() returns a nonzero value if the
- * inexact bit is already set, and clear_inexact() sets the
- * inexact bit to 0. When SET_INEXACT is #defined, strtod
- * also does extra computations to set the underflow and overflow
- * flags when appropriate (i.e., when the result is tiny and
- * inexact or when it is a numeric value rounded to +-infinity).
- * #define NO_ERRNO if strtod should not assign errno = ERANGE when
- * the result overflows to +-Infinity or underflows to 0.
- * #define NO_HEX_FP to omit recognition of hexadecimal floating-point
- * values by strtod.
- * #define NO_STRTOD_BIGCOMP (on IEEE-arithmetic systems only for now)
- * to disable logic for "fast" testing of very long input strings
- * to strtod. This testing proceeds by initially truncating the
- * input string, then if necessary comparing the whole string with
- * a decimal expansion to decide close cases. This logic is only
- * used for input more than STRTOD_DIGLIM digits long (default 40).
- */
- #include "dtoa_config.h"
- #ifndef Long
- #define Long long
- #endif
- #ifndef ULong
- typedef unsigned Long ULong;
- #endif
- #ifdef DEBUG
- #include "stdio.h"
- #define Bug(x) {fprintf(stderr, "%s\n", x); exit(1);}
- #endif
- #include "stdlib.h"
- #include "string.h"
- #ifdef USE_LOCALE
- #include "locale.h"
- #endif
- #ifdef Honor_FLT_ROUNDS
- #ifndef Trust_FLT_ROUNDS
- #include <fenv.h>
- #endif
- #endif
- #ifdef MALLOC
- #ifdef KR_headers
- extern char *MALLOC();
- #else
- extern void *MALLOC(size_t);
- #endif
- #else
- #define MALLOC malloc
- #endif
- #ifndef Omit_Private_Memory
- #ifndef PRIVATE_MEM
- #define PRIVATE_MEM 2304
- #endif
- #define PRIVATE_mem ((PRIVATE_MEM+sizeof(double)-1)/sizeof(double))
- static double private_mem[PRIVATE_mem], *pmem_next = private_mem;
- #endif
- #undef IEEE_Arith
- #undef Avoid_Underflow
- #ifdef IEEE_MC68k
- #define IEEE_Arith
- #endif
- #ifdef IEEE_8087
- #define IEEE_Arith
- #endif
- #ifdef IEEE_Arith
- #ifndef NO_INFNAN_CHECK
- #undef INFNAN_CHECK
- #define INFNAN_CHECK
- #endif
- #else
- #undef INFNAN_CHECK
- #define NO_STRTOD_BIGCOMP
- #endif
- #include "errno.h"
- #ifdef Bad_float_h
- #ifdef IEEE_Arith
- #define DBL_DIG 15
- #define DBL_MAX_10_EXP 308
- #define DBL_MAX_EXP 1024
- #define FLT_RADIX 2
- #endif /*IEEE_Arith*/
- #ifdef IBM
- #define DBL_DIG 16
- #define DBL_MAX_10_EXP 75
- #define DBL_MAX_EXP 63
- #define FLT_RADIX 16
- #define DBL_MAX 7.2370055773322621e+75
- #endif
- #ifdef VAX
- #define DBL_DIG 16
- #define DBL_MAX_10_EXP 38
- #define DBL_MAX_EXP 127
- #define FLT_RADIX 2
- #define DBL_MAX 1.7014118346046923e+38
- #endif
- #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
- #ifdef __cplusplus
- extern "C" {
- #endif
- #ifndef CONST
- #ifdef KR_headers
- #define CONST /* blank */
- #else
- #define CONST const
- #endif
- #endif
- #if defined(IEEE_8087) + defined(IEEE_MC68k) + defined(VAX) + defined(IBM) != 1
- Exactly one of IEEE_8087, IEEE_MC68k, VAX, or IBM should be defined.
- #endif
- typedef union { double d; ULong L[2]; } U;
- #ifdef IEEE_8087
- #define word0(x) (x)->L[1]
- #define word1(x) (x)->L[0]
- #else
- #define word0(x) (x)->L[0]
- #define word1(x) (x)->L[1]
- #endif
- #define dval(x) (x)->d
- #ifndef STRTOD_DIGLIM
- #define STRTOD_DIGLIM 40
- #endif
- #ifdef DIGLIM_DEBUG
- extern int strtod_diglim;
- #else
- #define strtod_diglim STRTOD_DIGLIM
- #endif
- /* The following definition of Storeinc is appropriate for MIPS processors.
- * An alternative that might be better on some machines is
- * #define Storeinc(a,b,c) (*a++ = b << 16 | c & 0xffff)
- */
- #if defined(IEEE_8087) + defined(VAX)
- #define Storeinc(a,b,c) (((unsigned short *)a)[1] = (unsigned short)b, \
- ((unsigned short *)a)[0] = (unsigned short)c, a++)
- #else
- #define Storeinc(a,b,c) (((unsigned short *)a)[0] = (unsigned short)b, \
- ((unsigned short *)a)[1] = (unsigned short)c, a++)
- #endif
- /* #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) */
- #ifdef IEEE_Arith
- #define Exp_shift 20
- #define Exp_shift1 20
- #define Exp_msk1 0x100000
- #define Exp_msk11 0x100000
- #define Exp_mask 0x7ff00000
- #define P 53
- #define Nbits 53
- #define Bias 1023
- #define Emax 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
- #ifndef NO_IEEE_Scale
- #define Avoid_Underflow
- #ifdef Flush_Denorm /* debugging option */
- #undef Sudden_Underflow
- #endif
- #endif
- #ifndef Flt_Rounds
- #ifdef FLT_ROUNDS
- #define Flt_Rounds FLT_ROUNDS
- #else
- #define Flt_Rounds 1
- #endif
- #endif /*Flt_Rounds*/
- #ifdef Honor_FLT_ROUNDS
- #undef Check_FLT_ROUNDS
- #define Check_FLT_ROUNDS
- #else
- #define Rounding Flt_Rounds
- #endif
- #else /* ifndef IEEE_Arith */
- #undef Check_FLT_ROUNDS
- #undef Honor_FLT_ROUNDS
- #undef SET_INEXACT
- #undef Sudden_Underflow
- #define Sudden_Underflow
- #ifdef IBM
- #undef Flt_Rounds
- #define Flt_Rounds 0
- #define Exp_shift 24
- #define Exp_shift1 24
- #define Exp_msk1 0x1000000
- #define Exp_msk11 0x1000000
- #define Exp_mask 0x7f000000
- #define P 14
- #define Nbits 56
- #define Bias 65
- #define Emax 248
- #define Emin (-260)
- #define Exp_1 0x41000000
- #define Exp_11 0x41000000
- #define Ebits 8 /* exponent has 7 bits, but 8 is the right value in b2d */
- #define Frac_mask 0xffffff
- #define Frac_mask1 0xffffff
- #define Bletch 4
- #define Ten_pmax 22
- #define Bndry_mask 0xefffff
- #define Bndry_mask1 0xffffff
- #define LSB 1
- #define Sign_bit 0x80000000
- #define Log2P 4
- #define Tiny0 0x100000
- #define Tiny1 0
- #define Quick_max 14
- #define Int_max 15
- #else /* VAX */
- #undef Flt_Rounds
- #define Flt_Rounds 1
- #define Exp_shift 23
- #define Exp_shift1 7
- #define Exp_msk1 0x80
- #define Exp_msk11 0x800000
- #define Exp_mask 0x7f80
- #define P 56
- #define Nbits 56
- #define Bias 129
- #define Emax 126
- #define Emin (-129)
- #define Exp_1 0x40800000
- #define Exp_11 0x4080
- #define Ebits 8
- #define Frac_mask 0x7fffff
- #define Frac_mask1 0xffff007f
- #define Ten_pmax 24
- #define Bletch 2
- #define Bndry_mask 0xffff007f
- #define Bndry_mask1 0xffff007f
- #define LSB 0x10000
- #define Sign_bit 0x8000
- #define Log2P 1
- #define Tiny0 0x80
- #define Tiny1 0
- #define Quick_max 15
- #define Int_max 15
- #endif /* IBM, VAX */
- #endif /* IEEE_Arith */
- #ifndef IEEE_Arith
- #define ROUND_BIASED
- #else
- #ifdef ROUND_BIASED_without_Round_Up
- #undef ROUND_BIASED
- #define ROUND_BIASED
- #endif
- #endif
- #ifdef RND_PRODQUOT
- #define rounded_product(a,b) a = rnd_prod(a, b)
- #define rounded_quotient(a,b) a = rnd_quot(a, b)
- #ifdef KR_headers
- extern double rnd_prod(), rnd_quot();
- #else
- extern double rnd_prod(double, double), rnd_quot(double, double);
- #endif
- #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 Pack_32
- #define Pack_32
- #endif
- typedef struct BCinfo BCinfo;
- struct
- BCinfo { int dp0, dp1, dplen, dsign, e0, inexact, nd, nd0, rounding, scale, uflchk; };
- #ifdef KR_headers
- #define FFFFFFFF ((((unsigned long)0xffff)<<16)|(unsigned long)0xffff)
- #else
- #define FFFFFFFF 0xffffffffUL
- #endif
- #ifdef NO_LONG_LONG
- #undef ULLong
- #ifdef Just_16
- #undef Pack_32
- /* When Pack_32 is not defined, we store 16 bits per 32-bit Long.
- * This makes some inner loops simpler and sometimes saves work
- * during multiplications, but it often seems to make things slightly
- * slower. Hence the default is now to store 32 bits per Long.
- */
- #endif
- #else /* long long available */
- #ifndef Llong
- #define Llong long long
- #endif
- #ifndef ULLong
- #define ULLong unsigned Llong
- #endif
- #endif /* NO_LONG_LONG */
- #ifndef MULTIPLE_THREADS
- #define ACQUIRE_DTOA_LOCK(n) /*nothing*/
- #define FREE_DTOA_LOCK(n) /*nothing*/
- #endif
- #define Kmax 7
- #ifdef __cplusplus
- extern "C" double fpconv_strtod(const char *s00, char **se);
- extern "C" char *dtoa(double d, int mode, int ndigits,
- int *decpt, int *sign, char **rve);
- #endif
- struct
- Bigint {
- struct Bigint *next;
- int k, maxwds, sign, wds;
- ULong x[1];
- };
- typedef struct Bigint Bigint;
- static Bigint *freelist[Kmax+1];
- static Bigint *
- Balloc
- #ifdef KR_headers
- (k) int k;
- #else
- (int k)
- #endif
- {
- int x;
- Bigint *rv;
- #ifndef Omit_Private_Memory
- unsigned int len;
- #endif
- ACQUIRE_DTOA_LOCK(0);
- /* The k > Kmax case does not need ACQUIRE_DTOA_LOCK(0), */
- /* but this case seems very unlikely. */
- if (k <= Kmax && (rv = freelist[k]))
- freelist[k] = rv->next;
- else {
- 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 (k <= Kmax && pmem_next - private_mem + len <= PRIVATE_mem) {
- rv = (Bigint*)pmem_next;
- pmem_next += len;
- }
- else
- rv = (Bigint*)MALLOC(len*sizeof(double));
- #endif
- rv->k = k;
- rv->maxwds = x;
- }
- FREE_DTOA_LOCK(0);
- rv->sign = rv->wds = 0;
- return rv;
- }
- static void
- Bfree
- #ifdef KR_headers
- (v) Bigint *v;
- #else
- (Bigint *v)
- #endif
- {
- if (v) {
- if (v->k > Kmax)
- #ifdef FREE
- FREE((void*)v);
- #else
- free((void*)v);
- #endif
- else {
- ACQUIRE_DTOA_LOCK(0);
- v->next = freelist[v->k];
- freelist[v->k] = v;
- FREE_DTOA_LOCK(0);
- }
- }
- }
- #define Bcopy(x,y) memcpy((char *)&x->sign, (char *)&y->sign, \
- y->wds*sizeof(Long) + 2*sizeof(int))
- static Bigint *
- multadd
- #ifdef KR_headers
- (b, m, a) Bigint *b; int m, a;
- #else
- (Bigint *b, int m, int a) /* multiply by m and add a */
- #endif
- {
- int i, wds;
- #ifdef ULLong
- ULong *x;
- ULLong carry, y;
- #else
- ULong carry, *x, y;
- #ifdef Pack_32
- ULong xi, z;
- #endif
- #endif
- Bigint *b1;
- wds = b->wds;
- x = b->x;
- i = 0;
- carry = a;
- do {
- #ifdef ULLong
- y = *x * (ULLong)m + carry;
- carry = y >> 32;
- *x++ = y & FFFFFFFF;
- #else
- #ifdef Pack_32
- xi = *x;
- y = (xi & 0xffff) * m + carry;
- z = (xi >> 16) * m + (y >> 16);
- carry = z >> 16;
- *x++ = (z << 16) + (y & 0xffff);
- #else
- y = *x * m + carry;
- carry = y >> 16;
- *x++ = y & 0xffff;
- #endif
- #endif
- }
- while(++i < wds);
- if (carry) {
- if (wds >= b->maxwds) {
- b1 = Balloc(b->k+1);
- Bcopy(b1, b);
- Bfree(b);
- b = b1;
- }
- b->x[wds++] = carry;
- b->wds = wds;
- }
- return b;
- }
- static Bigint *
- s2b
- #ifdef KR_headers
- (s, nd0, nd, y9, dplen) CONST char *s; int nd0, nd, dplen; ULong y9;
- #else
- (const char *s, int nd0, int nd, ULong y9, int dplen)
- #endif
- {
- Bigint *b;
- int i, k;
- Long x, y;
- x = (nd + 8) / 9;
- for(k = 0, y = 1; x > y; y <<= 1, k++) ;
- #ifdef Pack_32
- b = Balloc(k);
- b->x[0] = y9;
- b->wds = 1;
- #else
- b = Balloc(k+1);
- b->x[0] = y9 & 0xffff;
- b->wds = (b->x[1] = y9 >> 16) ? 2 : 1;
- #endif
- i = 9;
- if (9 < nd0) {
- s += 9;
- do b = multadd(b, 10, *s++ - '0');
- while(++i < nd0);
- s += dplen;
- }
- else
- s += dplen + 9;
- for(; i < nd; i++)
- b = multadd(b, 10, *s++ - '0');
- return b;
- }
- static int
- hi0bits
- #ifdef KR_headers
- (x) ULong x;
- #else
- (ULong x)
- #endif
- {
- int 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;
- }
- static int
- lo0bits
- #ifdef KR_headers
- (y) ULong *y;
- #else
- (ULong *y)
- #endif
- {
- int k;
- 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)
- return 32;
- }
- *y = x;
- return k;
- }
- static Bigint *
- i2b
- #ifdef KR_headers
- (i) int i;
- #else
- (int i)
- #endif
- {
- Bigint *b;
- b = Balloc(1);
- b->x[0] = i;
- b->wds = 1;
- return b;
- }
- static Bigint *
- mult
- #ifdef KR_headers
- (a, b) Bigint *a, *b;
- #else
- (Bigint *a, Bigint *b)
- #endif
- {
- Bigint *c;
- int k, wa, wb, wc;
- ULong *x, *xa, *xae, *xb, *xbe, *xc, *xc0;
- ULong y;
- #ifdef ULLong
- ULLong carry, z;
- #else
- ULong carry, z;
- #ifdef Pack_32
- ULong z2;
- #endif
- #endif
- if (a->wds < b->wds) {
- c = a;
- a = b;
- b = c;
- }
- k = a->k;
- wa = a->wds;
- wb = b->wds;
- wc = wa + wb;
- if (wc > a->maxwds)
- k++;
- c = Balloc(k);
- for(x = c->x, xa = x + wc; x < xa; x++)
- *x = 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++)) {
- x = xa;
- xc = xc0;
- carry = 0;
- do {
- z = *x++ * (ULLong)y + *xc + carry;
- carry = z >> 32;
- *xc++ = z & FFFFFFFF;
- }
- while(x < xae);
- *xc = carry;
- }
- }
- #else
- #ifdef Pack_32
- for(; xb < xbe; xb++, xc0++) {
- if (y = *xb & 0xffff) {
- 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) {
- 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;
- }
- }
- #else
- for(; xb < xbe; xc0++) {
- if (y = *xb++) {
- x = xa;
- xc = xc0;
- carry = 0;
- do {
- z = *x++ * y + *xc + carry;
- carry = z >> 16;
- *xc++ = z & 0xffff;
- }
- while(x < xae);
- *xc = carry;
- }
- }
- #endif
- #endif
- for(xc0 = c->x, xc = xc0 + wc; wc > 0 && !*--xc; --wc) ;
- c->wds = wc;
- return c;
- }
- static Bigint *p5s;
- static Bigint *
- pow5mult
- #ifdef KR_headers
- (b, k) Bigint *b; int k;
- #else
- (Bigint *b, int k)
- #endif
- {
- Bigint *b1, *p5, *p51;
- int i;
- static int p05[3] = { 5, 25, 125 };
- if ((i = k & 3))
- b = multadd(b, p05[i-1], 0);
- if (!(k >>= 2))
- return b;
- if (!(p5 = p5s)) {
- /* first time */
- #ifdef MULTIPLE_THREADS
- ACQUIRE_DTOA_LOCK(1);
- if (!(p5 = p5s)) {
- p5 = p5s = i2b(625);
- p5->next = 0;
- }
- FREE_DTOA_LOCK(1);
- #else
- p5 = p5s = i2b(625);
- p5->next = 0;
- #endif
- }
- for(;;) {
- if (k & 1) {
- b1 = mult(b, p5);
- Bfree(b);
- b = b1;
- }
- if (!(k >>= 1))
- break;
- if (!(p51 = p5->next)) {
- #ifdef MULTIPLE_THREADS
- ACQUIRE_DTOA_LOCK(1);
- if (!(p51 = p5->next)) {
- p51 = p5->next = mult(p5,p5);
- p51->next = 0;
- }
- FREE_DTOA_LOCK(1);
- #else
- p51 = p5->next = mult(p5,p5);
- p51->next = 0;
- #endif
- }
- p5 = p51;
- }
- return b;
- }
- static Bigint *
- lshift
- #ifdef KR_headers
- (b, k) Bigint *b; int k;
- #else
- (Bigint *b, int k)
- #endif
- {
- int i, k1, n, n1;
- Bigint *b1;
- ULong *x, *x1, *xe, z;
- #ifdef Pack_32
- n = k >> 5;
- #else
- n = k >> 4;
- #endif
- k1 = b->k;
- n1 = n + b->wds + 1;
- for(i = b->maxwds; n1 > i; i <<= 1)
- k1++;
- b1 = Balloc(k1);
- x1 = b1->x;
- for(i = 0; i < n; i++)
- *x1++ = 0;
- x = b->x;
- xe = x + b->wds;
- #ifdef Pack_32
- if (k &= 0x1f) {
- k1 = 32 - k;
- z = 0;
- do {
- *x1++ = *x << k | z;
- z = *x++ >> k1;
- }
- while(x < xe);
- if ((*x1 = z))
- ++n1;
- }
- #else
- if (k &= 0xf) {
- k1 = 16 - k;
- z = 0;
- do {
- *x1++ = *x << k & 0xffff | z;
- z = *x++ >> k1;
- }
- while(x < xe);
- if (*x1 = z)
- ++n1;
- }
- #endif
- else do
- *x1++ = *x++;
- while(x < xe);
- b1->wds = n1 - 1;
- Bfree(b);
- return b1;
- }
- static int
- cmp
- #ifdef KR_headers
- (a, b) Bigint *a, *b;
- #else
- (Bigint *a, Bigint *b)
- #endif
- {
- ULong *xa, *xa0, *xb, *xb0;
- int 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
- #ifdef KR_headers
- (a, b) Bigint *a, *b;
- #else
- (Bigint *a, Bigint *b)
- #endif
- {
- Bigint *c;
- int i, wa, wb;
- ULong *xa, *xae, *xb, *xbe, *xc;
- #ifdef ULLong
- ULLong borrow, y;
- #else
- ULong borrow, y;
- #ifdef Pack_32
- ULong z;
- #endif
- #endif
- i = cmp(a,b);
- if (!i) {
- c = Balloc(0);
- 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);
- 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 & (ULong)1;
- *xc++ = y & FFFFFFFF;
- }
- while(xb < xbe);
- while(xa < xae) {
- y = *xa++ - borrow;
- borrow = y >> 32 & (ULong)1;
- *xc++ = y & FFFFFFFF;
- }
- #else
- #ifdef Pack_32
- 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);
- }
- #else
- do {
- y = *xa++ - *xb++ - borrow;
- borrow = (y & 0x10000) >> 16;
- *xc++ = y & 0xffff;
- }
- while(xb < xbe);
- while(xa < xae) {
- y = *xa++ - borrow;
- borrow = (y & 0x10000) >> 16;
- *xc++ = y & 0xffff;
- }
- #endif
- #endif
- while(!*--xc)
- wa--;
- c->wds = wa;
- return c;
- }
- static double
- ulp
- #ifdef KR_headers
- (x) U *x;
- #else
- (U *x)
- #endif
- {
- Long L;
- U u;
- L = (word0(x) & Exp_mask) - (P-1)*Exp_msk1;
- #ifndef Avoid_Underflow
- #ifndef Sudden_Underflow
- if (L > 0) {
- #endif
- #endif
- #ifdef IBM
- L |= Exp_msk1 >> 4;
- #endif
- word0(&u) = L;
- word1(&u) = 0;
- #ifndef Avoid_Underflow
- #ifndef Sudden_Underflow
- }
- else {
- L = -L >> Exp_shift;
- if (L < Exp_shift) {
- word0(&u) = 0x80000 >> L;
- word1(&u) = 0;
- }
- else {
- word0(&u) = 0;
- L -= Exp_shift;
- word1(&u) = L >= 31 ? 1 : 1 << 31 - L;
- }
- }
- #endif
- #endif
- return dval(&u);
- }
- static double
- b2d
- #ifdef KR_headers
- (a, e) Bigint *a; int *e;
- #else
- (Bigint *a, int *e)
- #endif
- {
- ULong *xa, *xa0, w, y, z;
- int k;
- U d;
- #ifdef VAX
- ULong d0, d1;
- #else
- #define d0 word0(&d)
- #define d1 word1(&d)
- #endif
- 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;
- #ifdef Pack_32
- if (k < Ebits) {
- d0 = Exp_1 | y >> (Ebits - k);
- w = xa > xa0 ? *--xa : 0;
- d1 = y << ((32-Ebits) + k) | w >> (Ebits - k);
- goto ret_d;
- }
- z = xa > xa0 ? *--xa : 0;
- if (k -= Ebits) {
- d0 = Exp_1 | y << k | z >> (32 - k);
- y = xa > xa0 ? *--xa : 0;
- d1 = z << k | y >> (32 - k);
- }
- else {
- d0 = Exp_1 | y;
- d1 = z;
- }
- #else
- if (k < Ebits + 16) {
- z = xa > xa0 ? *--xa : 0;
- d0 = Exp_1 | y << k - Ebits | z >> Ebits + 16 - k;
- w = xa > xa0 ? *--xa : 0;
- y = xa > xa0 ? *--xa : 0;
- d1 = z << k + 16 - Ebits | w << k - Ebits | y >> 16 + Ebits - k;
- goto ret_d;
- }
- z = xa > xa0 ? *--xa : 0;
- w = xa > xa0 ? *--xa : 0;
- k -= Ebits + 16;
- d0 = Exp_1 | y << k + 16 | z << k | w >> 16 - k;
- y = xa > xa0 ? *--xa : 0;
- d1 = w << k + 16 | y << k;
- #endif
- ret_d:
- #ifdef VAX
- word0(&d) = d0 >> 16 | d0 << 16;
- word1(&d) = d1 >> 16 | d1 << 16;
- #else
- #undef d0
- #undef d1
- #endif
- return dval(&d);
- }
- static Bigint *
- d2b
- #ifdef KR_headers
- (d, e, bits) U *d; int *e, *bits;
- #else
- (U *d, int *e, int *bits)
- #endif
- {
- Bigint *b;
- int de, k;
- ULong *x, y, z;
- #ifndef Sudden_Underflow
- int i;
- #endif
- #ifdef VAX
- ULong d0, d1;
- d0 = word0(d) >> 16 | word0(d) << 16;
- d1 = word1(d) >> 16 | word1(d) << 16;
- #else
- #define d0 word0(d)
- #define d1 word1(d)
- #endif
- #ifdef Pack_32
- b = Balloc(1);
- #else
- b = Balloc(2);
- #endif
- x = b->x;
- z = d0 & Frac_mask;
- d0 &= 0x7fffffff; /* clear sign bit, which we ignore */
- #ifdef Sudden_Underflow
- de = (int)(d0 >> Exp_shift);
- #ifndef IBM
- z |= Exp_msk11;
- #endif
- #else
- if ((de = (int)(d0 >> Exp_shift)))
- z |= Exp_msk1;
- #endif
- #ifdef Pack_32
- if ((y = d1)) {
- if ((k = lo0bits(&y))) {
- x[0] = y | z << (32 - k);
- z >>= k;
- }
- else
- x[0] = y;
- #ifndef Sudden_Underflow
- i =
- #endif
- b->wds = (x[1] = z) ? 2 : 1;
- }
- else {
- k = lo0bits(&z);
- x[0] = z;
- #ifndef Sudden_Underflow
- i =
- #endif
- b->wds = 1;
- k += 32;
- }
- #else
- if (y = d1) {
- if (k = lo0bits(&y))
- if (k >= 16) {
- x[0] = y | z << 32 - k & 0xffff;
- x[1] = z >> k - 16 & 0xffff;
- x[2] = z >> k;
- i = 2;
- }
- else {
- x[0] = y & 0xffff;
- x[1] = y >> 16 | z << 16 - k & 0xffff;
- x[2] = z >> k & 0xffff;
- x[3] = z >> k+16;
- i = 3;
- }
- else {
- x[0] = y & 0xffff;
- x[1] = y >> 16;
- x[2] = z & 0xffff;
- x[3] = z >> 16;
- i = 3;
- }
- }
- else {
- #ifdef DEBUG
- if (!z)
- Bug("Zero passed to d2b");
- #endif
- k = lo0bits(&z);
- if (k >= 16) {
- x[0] = z;
- i = 0;
- }
- else {
- x[0] = z & 0xffff;
- x[1] = z >> 16;
- i = 1;
- }
- k += 32;
- }
- while(!x[i])
- --i;
- b->wds = i + 1;
- #endif
- #ifndef Sudden_Underflow
- if (de) {
- #endif
- #ifdef IBM
- *e = (de - Bias - (P-1) << 2) + k;
- *bits = 4*P + 8 - k - hi0bits(word0(d) & Frac_mask);
- #else
- *e = de - Bias - (P-1) + k;
- *bits = P - k;
- #endif
- #ifndef Sudden_Underflow
- }
- else {
- *e = de - Bias - (P-1) + 1 + k;
- #ifdef Pack_32
- *bits = 32*i - hi0bits(x[i-1]);
- #else
- *bits = (i+2)*16 - hi0bits(x[i]);
- #endif
- }
- #endif
- return b;
- }
- #undef d0
- #undef d1
- static double
- ratio
- #ifdef KR_headers
- (a, b) Bigint *a, *b;
- #else
- (Bigint *a, Bigint *b)
- #endif
- {
- U da, db;
- int k, ka, kb;
- dval(&da) = b2d(a, &ka);
- dval(&db) = b2d(b, &kb);
- #ifdef Pack_32
- k = ka - kb + 32*(a->wds - b->wds);
- #else
- k = ka - kb + 16*(a->wds - b->wds);
- #endif
- #ifdef IBM
- if (k > 0) {
- word0(&da) += (k >> 2)*Exp_msk1;
- if (k &= 3)
- dval(&da) *= 1 << k;
- }
- else {
- k = -k;
- word0(&db) += (k >> 2)*Exp_msk1;
- if (k &= 3)
- dval(&db) *= 1 << k;
- }
- #else
- if (k > 0)
- word0(&da) += k*Exp_msk1;
- else {
- k = -k;
- word0(&db) += k*Exp_msk1;
- }
- #endif
- return dval(&da) / dval(&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
- #ifdef VAX
- , 1e23, 1e24
- #endif
- };
- static CONST double
- #ifdef IEEE_Arith
- bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };
- static CONST double tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128,
- #ifdef Avoid_Underflow
- 9007199254740992.*9007199254740992.e-256
- /* = 2^106 * 1e-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
- #else
- #ifdef IBM
- bigtens[] = { 1e16, 1e32, 1e64 };
- static CONST double tinytens[] = { 1e-16, 1e-32, 1e-64 };
- #define n_bigtens 3
- #else
- bigtens[] = { 1e16, 1e32 };
- static CONST double tinytens[] = { 1e-16, 1e-32 };
- #define n_bigtens 2
- #endif
- #endif
- #undef Need_Hexdig
- #ifdef INFNAN_CHECK
- #ifndef No_Hex_NaN
- #define Need_Hexdig
- #endif
- #endif
- #ifndef Need_Hexdig
- #ifndef NO_HEX_FP
- #define Need_Hexdig
- #endif
- #endif
- #ifdef Need_Hexdig /*{*/
- static unsigned char hexdig[256];
- static void
- #ifdef KR_headers
- htinit(h, s, inc) unsigned char *h; unsigned char *s; int inc;
- #else
- htinit(unsigned char *h, unsigned char *s, int inc)
- #endif
- {
- int i, j;
- for(i = 0; (j = s[i]) !=0; i++)
- h[j] = i + inc;
- }
- static void
- #ifdef KR_headers
- hexdig_init()
- #else
- hexdig_init(void)
- #endif
- {
- #define USC (unsigned char *)
- htinit(hexdig, USC "0123456789", 0x10);
- htinit(hexdig, USC "abcdef", 0x10 + 10);
- htinit(hexdig, USC "ABCDEF", 0x10 + 10);
- }
- #endif /* } Need_Hexdig */
- #ifdef INFNAN_CHECK
- #ifndef NAN_WORD0
- #define NAN_WORD0 0x7ff80000
- #endif
- #ifndef NAN_WORD1
- #define NAN_WORD1 0
- #endif
- static int
- match
- #ifdef KR_headers
- (sp, t) char **sp, *t;
- #else
- (const char **sp, const char *t)
- #endif
- {
- 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;
- }
- #ifndef No_Hex_NaN
- static void
- hexnan
- #ifdef KR_headers
- (rvp, sp) U *rvp; CONST char **sp;
- #else
- (U *rvp, const char **sp)
- #endif
- {
- ULong c, x[2];
- CONST char *s;
- int c1, havedig, udx0, xshift;
- if (!hexdig['0'])
- hexdig_init();
- x[0] = x[1] = 0;
- havedig = xshift = 0;
- udx0 = 1;
- s = *sp;
- /* allow optional initial 0x or 0X */
- while((c = *(CONST unsigned char*)(s+1)) && c <= ' ')
- ++s;
- if (s[1] == '0' && (s[2] == 'x' || s[2] == 'X'))
- s += 2;
- while((c = *(CONST unsigned char*)++s)) {
- if ((c1 = hexdig[c]))
- c = c1 & 0xf;
- else if (c <= ' ') {
- if (udx0 && havedig) {
- udx0 = 0;
- xshift = 1;
- }
- continue;
- }
- #ifdef GDTOA_NON_PEDANTIC_NANCHECK
- else if (/*(*/ c == ')' && havedig) {
- *sp = s + 1;
- break;
- }
- else
- return; /* invalid form: don't change *sp */
- #else
- else {
- do {
- if (/*(*/ c == ')') {
- *sp = s + 1;
- break;
- }
- } while((c = *++s));
- break;
- }
- #endif
- havedig = 1;
- if (xshift) {
- xshift = 0;
- x[0] = x[1];
- x[1] = 0;
- }
- if (udx0)
- x[0] = (x[0] << 4) | (x[1] >> 28);
- x[1] = (x[1] << 4) | c;
- }
- if ((x[0] &= 0xfffff) || x[1]) {
- word0(rvp) = Exp_mask | x[0];
- word1(rvp) = x[1];
- }
- }
- #endif /*No_Hex_NaN*/
- #endif /* INFNAN_CHECK */
- #ifdef Pack_32
- #define ULbits 32
- #define kshift 5
- #define kmask 31
- #else
- #define ULbits 16
- #define kshift 4
- #define kmask 15
- #endif
- #if !defined(NO_HEX_FP) || defined(Honor_FLT_ROUNDS) /*{*/
- static Bigint *
- #ifdef KR_headers
- increment(b) Bigint *b;
- #else
- increment(Bigint *b)
- #endif
- {
- ULong *x, *xe;
- Bigint *b1;
- x = b->x;
- xe = x + b->wds;
- do {
- if (*x < (ULong)0xffffffffL) {
- ++*x;
- return b;
- }
- *x++ = 0;
- } while(x < xe);
- {
- if (b->wds >= b->maxwds) {
- b1 = Balloc(b->k+1);
- Bcopy(b1,b);
- Bfree(b);
- b = b1;
- }
- b->x[b->wds++] = 1;
- }
- return b;
- }
- #endif /*}*/
- #ifndef NO_HEX_FP /*{*/
- static void
- #ifdef KR_headers
- rshift(b, k) Bigint *b; int k;
- #else
- rshift(Bigint *b, int k)
- #endif
- {
- ULong *x, *x1, *xe, y;
- int n;
- x = x1 = b->x;
- n = k >> kshift;
- if (n < b->wds) {
- xe = x + b->wds;
- x += n;
- if (k &= kmask) {
- n = 32 - k;
- y = *x++ >> k;
- while(x < xe) {
- *x1++ = (y | (*x << n)) & 0xffffffff;
- y = *x++ >> k;
- }
- if ((*x1 = y) !=0)
- x1++;
- }
- else
- while(x < xe)
- *x1++ = *x++;
- }
- if ((b->wds = x1 - b->x) == 0)
- b->x[0] = 0;
- }
- static ULong
- #ifdef KR_headers
- any_on(b, k) Bigint *b; int k;
- #else
- any_on(Bigint *b, int k)
- #endif
- {
- int n, nwds;
- ULong *x, *x0, x1, x2;
- x = b->x;
- nwds = b->wds;
- n = k >> kshift;
- if (n > nwds)
- n = nwds;
- else if (n < nwds && (k &= kmask)) {
- x1 = x2 = x[n];
- x1 >>= k;
- x1 <<= k;
- if (x1 != x2)
- return 1;
- }
- x0 = x;
- x += n;
- while(x > x0)
- if (*--x)
- return 1;
- return 0;
- }
- enum { /* rounding values: same as FLT_ROUNDS */
- Round_zero = 0,
- Round_near = 1,
- Round_up = 2,
- Round_down = 3
- };
- void
- #ifdef KR_headers
- gethex(sp, rvp, rounding, sign)
- CONST char **sp; U *rvp; int rounding, sign;
- #else
- gethex( CONST char **sp, U *rvp, int rounding, int sign)
- #endif
- {
- Bigint *b;
- CONST unsigned char *decpt, *s0, *s, *s1;
- Long e, e1;
- ULong L, lostbits, *x;
- int big, denorm, esign, havedig, k, n, nbits, up, zret;
- #ifdef IBM
- int j;
- #endif
- enum {
- #ifdef IEEE_Arith /*{{*/
- emax = 0x7fe - Bias - P + 1,
- emin = Emin - P + 1
- #else /*}{*/
- emin = Emin - P,
- #ifdef VAX
- emax = 0x7ff - Bias - P + 1
- #endif
- #ifdef IBM
- emax = 0x7f - Bias - P
- #endif
- #endif /*}}*/
- };
- #ifdef USE_LOCALE
- int i;
- #ifdef NO_LOCALE_CACHE
- const unsigned char *decimalpoint = (unsigned char*)
- localeconv()->decimal_point;
- #else
- const unsigned char *decimalpoint;
- static unsigned char *decimalpoint_cache;
- if (!(s0 = decimalpoint_cache)) {
- s0 = (unsigned char*)localeconv()->decimal_point;
- if ((decimalpoint_cache = (unsigned char*)
- MALLOC(strlen((CONST char*)s0) + 1))) {
- strcpy((char*)decimalpoint_cache, (CONST char*)s0);
- s0 = decimalpoint_cache;
- }
- }
- decimalpoint = s0;
- #endif
- #endif
- if (!hexdig['0'])
- hexdig_init();
- havedig = 0;
- s0 = *(CONST unsigned char **)sp + 2;
- while(s0[havedig] == '0')
- havedig++;
- s0 += havedig;
- s = s0;
- decpt = 0;
- zret = 0;
- e = 0;
- if (hexdig[*s])
- havedig++;
- else {
- zret = 1;
- #ifdef USE_LOCALE
- for(i = 0; decimalpoint[i]; ++i) {
- if (s[i] != decimalpoint[i])
- goto pcheck;
- }
- decpt = s += i;
- #else
- if (*s != '.')
- goto pcheck;
- decpt = ++s;
- #endif
- if (!hexdig[*s])
- goto pcheck;
- while(*s == '0')
- s++;
- if (hexdig[*s])
- zret = 0;
- havedig = 1;
- s0 = s;
- }
- while(hexdig[*s])
- s++;
- #ifdef USE_LOCALE
- if (*s == *decimalpoint && !decpt) {
- for(i = 1; decimalpoint[i]; ++i) {
- if (s[i] != decimalpoint[i])
- goto pcheck;
- }
- decpt = s += i;
- #else
- if (*s == '.' && !decpt) {
- decpt = ++s;
- #endif
- while(hexdig[*s])
- s++;
- }/*}*/
- if (decpt)
- e = -(((Long)(s-decpt)) << 2);
- pcheck:
- s1 = s;
- big = esign = 0;
- switch(*s) {
- case 'p':
- case 'P':
- switch(*++s) {
- case '-':
- esign = 1;
- /* no break */
- case '+':
- s++;
- }
- if ((n = hexdig[*s]) == 0 || n > 0x19) {
- s = s1;
- break;
- }
- e1 = n - 0x10;
- while((n = hexdig[*++s]) !=0 && n <= 0x19) {
- if (e1 & 0xf8000000)
- big = 1;
- e1 = 10*e1 + n - 0x10;
- }
- if (esign)
- e1 = -e1;
- e += e1;
- }
- *sp = (char*)s;
- if (!havedig)
- *sp = (char*)s0 - 1;
- if (zret)
- goto retz1;
- if (big) {
- if (esign) {
- #ifdef IEEE_Arith
- switch(rounding) {
- case Round_up:
- if (sign)
- break;
- goto ret_tiny;
- case Round_down:
- if (!sign)
- break;
- goto ret_tiny;
- }
- #endif
- goto retz;
- #ifdef IEEE_Arith
- ret_tiny:
- #ifndef NO_ERRNO
- errno = ERANGE;
- #endif
- word0(rvp) = 0;
- word1(rvp) = 1;
- return;
- #endif /* IEEE_Arith */
- }
- switch(rounding) {
- case Round_near:
- goto ovfl1;
- case Round_up:
- if (!sign)
- goto ovfl1;
- goto ret_big;
- case Round_down:
- if (sign)
- goto ovfl1;
- goto ret_big;
- }
- ret_big:
- word0(rvp) = Big0;
- word1(rvp) = Big1;
- return;
- }
- n = s1 - s0 - 1;
- for(k = 0; n > (1 << (kshift-2)) - 1; n >>= 1)
- k++;
- b = Balloc(k);
- x = b->x;
- n = 0;
- L = 0;
- #ifdef USE_LOCALE
- for(i = 0; decimalpoint[i+1]; ++i);
- #endif
- while(s1 > s0) {
- #ifdef USE_LOCALE
- if (*--s1 == decimalpoint[i]) {
- s1 -= i;
- continue;
- }
- #else
- if (*--s1 == '.')
- continue;
- #endif
- if (n == ULbits) {
- *x++ = L;
- L = 0;
- n = 0;
- }
- L |= (hexdig[*s1] & 0x0f) << n;
- n += 4;
- }
- *x++ = L;
- b->wds = n = x - b->x;
- n = ULbits*n - hi0bits(L);
- nbits = Nbits;
- lostbits = 0;
- x = b->x;
- if (n > nbits) {
- n -= nbits;
- if (any_on(b,n)) {
- lostbits = 1;
- k = n - 1;
- if (x[k>>kshift] & 1 << (k & kmask)) {
- lostbits = 2;
- if (k > 0 && any_on(b,k))
- lostbits = 3;
- }
- }
- rshift(b, n);
- e += n;
- }
- else if (n < nbits) {
- n = nbits - n;
- b = lshift(b, n);
- e -= n;
- x = b->x;
- }
- if (e > Emax) {
- ovfl:
- Bfree(b);
- ovfl1:
- #ifndef NO_ERRNO
- errno = ERANGE;
- #endif
- word0(rvp) = Exp_mask;
- word1(rvp) = 0;
- return;
- }
- denorm = 0;
- if (e < emin) {
- denorm = 1;
- n = emin - e;
- if (n >= nbits) {
- #ifdef IEEE_Arith /*{*/
- switch (rounding) {
- case Round_near:
- if (n == nbits && (n < 2 || any_on(b,n-1)))
- goto ret_tiny;
- break;
- case Round_up:
- if (!sign)
- goto ret_tiny;
- break;
- case Round_down:
- if (sign)
- goto ret_tiny;
- }
- #endif /* } IEEE_Arith */
- Bfree(b);
- retz:
- #ifndef NO_ERRNO
- errno = ERANGE;
- #endif
- retz1:
- rvp->d = 0.;
- return;
- }
- k = n - 1;
- if (lostbits)
- lostbits = 1;
- else if (k > 0)
- lostbits = any_on(b,k);
- if (x[k>>kshift] & 1 << (k & kmask))
- lostbits |= 2;
- nbits -= n;
- rshift(b,n);
- e = emin;
- }
- if (lostbits) {
- up = 0;
- switch(rounding) {
- case Round_zero:
- break;
- case Round_near:
- if (lostbits & 2
- && (lostbits & 1) | (x[0] & 1))
- up = 1;
- break;
- case Round_up:
- up = 1 - sign;
- break;
- case Round_down:
- up = sign;
- }
- if (up) {
- k = b->wds;
- b = increment(b);
- x = b->x;
- if (denorm) {
- #if 0
- if (nbits == Nbits - 1
- && x[nbits >> kshift] & 1 << (nbits & kmask))
- denorm = 0; /* not currently used */
- #endif
- }
- else if (b->wds > k
- || ((n = nbits & kmask) !=0
- && hi0bits(x[k-1]) < 32-n)) {
- rshift(b,1);
- if (++e > Emax)
- goto ovfl;
- }
- }
- }
- #ifdef IEEE_Arith
- if (denorm)
- word0(rvp) = b->wds > 1 ? b->x[1] & ~0x100000 : 0;
- else
- word0(rvp) = (b->x[1] & ~0x100000) | ((e + 0x3ff + 52) << 20);
- word1(rvp) = b->x[0];
- #endif
- #ifdef IBM
- if ((j = e & 3)) {
- k = b->x[0] & ((1 << j) - 1);
- rshift(b,j);
- if (k) {
- switch(rounding) {
- case Round_up:
- if (!sign)
- increment(b);
- break;
- case Round_down:
- if (sign)
- increment(b);
- break;
- case Round_near:
- j = 1 << (j-1);
- if (k & j && ((k & (j-1)) | lostbits))
- increment(b);
- }
- }
- }
- e >>= 2;
- word0(rvp) = b->x[1] | ((e + 65 + 13) << 24);
- word1(rvp) = b->x[0];
- #endif
- #ifdef VAX
- /* The next two lines ignore swap of low- and high-order 2 bytes. */
- /* word0(rvp) = (b->x[1] & ~0x800000) | ((e + 129 + 55) << 23); */
- /* word1(rvp) = b->x[0]; */
- word0(rvp) = ((b->x[1] & ~0x800000) >> 16) | ((e + 129 + 55) << 7) | (b->x[1] << 16);
- word1(rvp) = (b->x[0] >> 16) | (b->x[0] << 16);
- #endif
- Bfree(b);
- }
- #endif /*!NO_HEX_FP}*/
- static int
- #ifdef KR_headers
- dshift(b, p2) Bigint *b; int p2;
- #else
- dshift(Bigint *b, int p2)
- #endif
- {
- int rv = hi0bits(b->x[b->wds-1]) - 4;
- if (p2 > 0)
- rv -= p2;
- return rv & kmask;
- }
- static int
- quorem
- #ifdef KR_headers
- (b, S) Bigint *b, *S;
- #else
- (Bigint *b, Bigint *S)
- #endif
- {
- int n;
- ULong *bx, *bxe, q, *sx, *sxe;
- #ifdef ULLong
- ULLong borrow, carry, y, ys;
- #else
- ULong borrow, carry, y, ys;
- #ifdef Pack_32
- ULong si, z, zs;
- #endif
- #endif
- n = S->wds;
- #ifdef DEBUG
- /*debug*/ if (b->wds > n)
- /*debug*/ Bug("oversize b in quorem");
- #endif
- if (b->wds < n)
- return 0;
- sx = S->x;
- sxe = sx + --n;
- bx = b->x;
- bxe = bx + n;
- q = *bxe / (*sxe + 1); /* ensure q <= true quotient */
- #ifdef DEBUG
- #ifdef NO_STRTOD_BIGCOMP
- /*debug*/ if (q > 9)
- #else
- /* An oversized q is possible when quorem is called from bigcomp and */
- /* the input is near, e.g., twice the smallest denormalized number. */
- /*debug*/ if (q > 15)
- #endif
- /*debug*/ Bug("oversized quotient in quorem");
- #endif
- if (q) {
- borrow = 0;
- carry = 0;
- do {
- #ifdef ULLong
- ys = *sx++ * (ULLong)q + carry;
- carry = ys >> 32;
- y = *bx - (ys & FFFFFFFF) - borrow;
- borrow = y >> 32 & (ULong)1;
- *bx++ = y & FFFFFFFF;
- #else
- #ifdef Pack_32
- 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);
- #else
- ys = *sx++ * q + carry;
- carry = ys >> 16;
- y = *bx - (ys & 0xffff) - borrow;
- borrow = (y & 0x10000) >> 16;
- *bx++ = y & 0xffff;
- #endif
- #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 & FFFFFFFF) - borrow;
- borrow = y >> 32 & (ULong)1;
- *bx++ = y & FFFFFFFF;
- #else
- #ifdef Pack_32
- 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);
- #else
- ys = *sx++ + carry;
- carry = ys >> 16;
- y = *bx - (ys & 0xffff) - borrow;
- borrow = (y & 0x10000) >> 16;
- *bx++ = y & 0xffff;
- #endif
- #endif
- }
- while(sx <= sxe);
- bx = b->x;
- bxe = bx + n;
- if (!*bxe) {
- while(--bxe > bx && !*bxe)
- --n;
- b->wds = n;
- }
- }
- return q;
- }
- #if defined(Avoid_Underflow) || !defined(NO_STRTOD_BIGCOMP) /*{*/
- static double
- sulp
- #ifdef KR_headers
- (x, bc) U *x; BCinfo *bc;
- #else
- (U *x, BCinfo *bc)
- #endif
- {
- U u;
- double rv;
- int i;
- rv = ulp(x);
- if (!bc->scale || (i = 2*P + 1 - ((word0(x) & Exp_mask) >> Exp_shift)) <= 0)
- return rv; /* Is there an example where i <= 0 ? */
- word0(&u) = Exp_1 + (i << Exp_shift);
- word1(&u) = 0;
- return rv * u.d;
- }
- #endif /*}*/
- #ifndef NO_STRTOD_BIGCOMP
- static void
- bigcomp
- #ifdef KR_headers
- (rv, s0, bc)
- U *rv; CONST char *s0; BCinfo *bc;
- #else
- (U *rv, const char *s0, BCinfo *bc)
- #endif
- {
- Bigint *b, *d;
- int b2, bbits, d2, dd, dig, dsign, i, j, nd, nd0, p2, p5, speccase;
- dsign = bc->dsign;
- nd = bc->nd;
- nd0 = bc->nd0;
- p5 = nd + bc->e0 - 1;
- speccase = 0;
- #ifndef Sudden_Underflow
- if (rv->d == 0.) { /* special case: value near underflow-to-zero */
- /* threshold was rounded to zero */
- b = i2b(1);
- p2 = Emin - P + 1;
- bbits = 1;
- #ifdef Avoid_Underflow
- word0(rv) = (P+2) << Exp_shift;
- #else
- word1(rv) = 1;
- #endif
- i = 0;
- #ifdef Honor_FLT_ROUNDS
- if (bc->rounding == 1)
- #endif
- {
- speccase = 1;
- --p2;
- dsign = 0;
- goto have_i;
- }
- }
- else
- #endif
- b = d2b(rv, &p2, &bbits);
- #ifdef Avoid_Underflow
- p2 -= bc->scale;
- #endif
- /* floor(log2(rv)) == bbits - 1 + p2 */
- /* Check for denormal case. */
- i = P - bbits;
- if (i > (j = P - Emin - 1 + p2)) {
- #ifdef Sudden_Underflow
- Bfree(b);
- b = i2b(1);
- p2 = Emin;
- i = P - 1;
- #ifdef Avoid_Underflow
- word0(rv) = (1 + bc->scale) << Exp_shift;
- #else
- word0(rv) = Exp_msk1;
- #endif
- word1(rv) = 0;
- #else
- i = j;
- #endif
- }
- #ifdef Honor_FLT_ROUNDS
- if (bc->rounding != 1) {
- if (i > 0)
- b = lshift(b, i);
- if (dsign)
- b = increment(b);
- }
- else
- #endif
- {
- b = lshift(b, ++i);
- b->x[0] |= 1;
- }
- #ifndef Sudden_Underflow
- have_i:
- #endif
- p2 -= p5 + i;
- d = i2b(1);
- /* Arrange for convenient computation of quotients:
- * shift left if necessary so divisor has 4 leading 0 bits.
- */
- if (p5 > 0)
- d = pow5mult(d, p5);
- else if (p5 < 0)
- b = pow5mult(b, -p5);
- if (p2 > 0) {
- b2 = p2;
- d2 = 0;
- }
- else {
- b2 = 0;
- d2 = -p2;
- }
- i = dshift(d, d2);
- if ((b2 += i) > 0)
- b = lshift(b, b2);
- if ((d2 += i) > 0)
- d = lshift(d, d2);
- /* Now b/d = exactly half-way between the two floating-point values */
- /* on either side of the input string. Compute first digit of b/d. */
- if (!(dig = quorem(b,d))) {
- b = multadd(b, 10, 0); /* very unlikely */
- dig = quorem(b,d);
- }
- /* Compare b/d with s0 */
- for(i = 0; i < nd0; ) {
- if ((dd = s0[i++] - '0' - dig))
- goto ret;
- if (!b->x[0] && b->wds == 1) {
- if (i < nd)
- dd = 1;
- goto ret;
- }
- b = multadd(b, 10, 0);
- dig = quorem(b,d);
- }
- for(j = bc->dp1; i++ < nd;) {
- if ((dd = s0[j++] - '0' - dig))
- goto ret;
- if (!b->x[0] && b->wds == 1) {
- if (i < nd)
- dd = 1;
- goto ret;
- }
- b = multadd(b, 10, 0);
- dig = quorem(b,d);
- }
- if (b->x[0] || b->wds > 1)
- dd = -1;
- ret:
- Bfree(b);
- Bfree(d);
- #ifdef Honor_FLT_ROUNDS
- if (bc->rounding != 1) {
- if (dd < 0) {
- if (bc->rounding == 0) {
- if (!dsign)
- goto retlow1;
- }
- else if (dsign)
- goto rethi1;
- }
- else if (dd > 0) {
- if (bc->rounding == 0) {
- if (dsign)
- goto rethi1;
- goto ret1;
- }
- if (!dsign)
- goto rethi1;
- dval(rv) += 2.*sulp(rv,bc);
- }
- else {
- bc->inexact = 0;
- if (dsign)
- goto rethi1;
- }
- }
- else
- #endif
- if (speccase) {
- if (dd <= 0)
- rv->d = 0.;
- }
- else if (dd < 0) {
- if (!dsign) /* does not happen for round-near */
- retlow1:
- dval(rv) -= sulp(rv,bc);
- }
- else if (dd > 0) {
- if (dsign) {
- rethi1:
- dval(rv) += sulp(rv,bc);
- }
- }
- else {
- /* Exact half-way case: apply round-even rule. */
- if ((j = ((word0(rv) & Exp_mask) >> Exp_shift) - bc->scale) <= 0) {
- i = 1 - j;
- if (i <= 31) {
- if (word1(rv) & (0x1 << i))
- goto odd;
- }
- else if (word0(rv) & (0x1 << (i-32)))
- goto odd;
- }
- else if (word1(rv) & 1) {
- odd:
- if (dsign)
- goto rethi1;
- goto retlow1;
- }
- }
- #ifdef Honor_FLT_ROUNDS
- ret1:
- #endif
- return;
- }
- #endif /* NO_STRTOD_BIGCOMP */
- double
- fpconv_strtod
- #ifdef KR_headers
- (s00, se) CONST char *s00; char **se;
- #else
- (const char *s00, char **se)
- #endif
- {
- int bb2, bb5, bbe, bd2, bd5, bbbits, bs2, c, e, e1;
- int esign, i, j, k, nd, nd0, nf, nz, nz0, nz1, sign;
- CONST char *s, *s0, *s1;
- double aadj, aadj1;
- Long L;
- U aadj2, adj, rv, rv0;
- ULong y, z;
- BCinfo bc;
- Bigint *bb, *bb1, *bd, *bd0, *bs, *delta;
- #ifdef Avoid_Underflow
- ULong Lsb, Lsb1;
- #endif
- #ifdef SET_INEXACT
- int oldinexact;
- #endif
- #ifndef NO_STRTOD_BIGCOMP
- int req_bigcomp = 0;
- #endif
- #ifdef Honor_FLT_ROUNDS /*{*/
- #ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
- bc.rounding = Flt_Rounds;
- #else /*}{*/
- bc.rounding = 1;
- switch(fegetround()) {
- case FE_TOWARDZERO: bc.rounding = 0; break;
- case FE_UPWARD: bc.rounding = 2; break;
- case FE_DOWNWARD: bc.rounding = 3;
- }
- #endif /*}}*/
- #endif /*}*/
- #ifdef USE_LOCALE
- CONST char *s2;
- #endif
- sign = nz0 = nz1 = nz = bc.dplen = bc.uflchk = 0;
- dval(&rv) = 0.;
- for(s = s00;;s++) switch(*s) {
- case '-':
- sign = 1;
- /* no break */
- case '+':
- if (*++s)
- goto break2;
- /* no break */
- case 0:
- goto ret0;
- case '\t':
- case '\n':
- case '\v':
- case '\f':
- case '\r':
- case ' ':
- continue;
- default:
- goto break2;
- }
- break2:
- if (*s == '0') {
- #ifndef NO_HEX_FP /*{*/
- switch(s[1]) {
- case 'x':
- case 'X':
- #ifdef Honor_FLT_ROUNDS
- gethex(&s, &rv, bc.rounding, sign);
- #else
- gethex(&s, &rv, 1, sign);
- #endif
- goto ret;
- }
- #endif /*}*/
- 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;
- bc.dp0 = bc.dp1 = s - s0;
- for(s1 = s; s1 > s0 && *--s1 == '0'; )
- ++nz1;
- #ifdef USE_LOCALE
- s1 = localeconv()->decimal_point;
- if (c == *s1) {
- c = '.';
- if (*++s1) {
- s2 = s;
- for(;;) {
- if (*++s2 != *s1) {
- c = 0;
- break;
- }
- if (!*++s1) {
- s = s2;
- break;
- }
- }
- }
- }
- #endif
- if (c == '.') {
- c = *++s;
- bc.dp1 = s - s0;
- bc.dplen = bc.dp1 - bc.dp0;
- if (!nd) {
- for(; c == '0'; c = *++s)
- nz++;
- if (c > '0' && c <= '9') {
- bc.dp0 = s0 - s;
- bc.dp1 = bc.dp0 + bc.dplen;
- 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 = nz1 = 0;
- }
- }
- }
- dig_done:
- e = 0;
- if (c == 'e' || c == 'E') {
- if (!nd && !nz && !nz0) {
- goto ret0;
- }
- 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 = (int)L;
- if (esign)
- e = -e;
- }
- else
- e = 0;
- }
- else
- s = s00;
- }
- if (!nd) {
- if (!nz && !nz0) {
- #ifdef INFNAN_CHECK
- /* Check for Nan and Infinity */
- if (!bc.dplen)
- switch(c) {
- case 'i':
- case 'I':
- if (match(&s,"nf")) {
- --s;
- if (!match(&s,"inity"))
- ++s;
- 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;
- #ifndef No_Hex_NaN
- if (*s == '(') /*)*/
- hexnan(&rv, &s);
- #endif
- goto ret;
- }
- }
- #endif /* INFNAN_CHECK */
- ret0:
- s = s00;
- sign = 0;
- }
- goto ret;
- }
- bc.e0 = 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;
- dval(&rv) = y;
- if (k > 9) {
- #ifdef SET_INEXACT
- if (k > DBL_DIG)
- oldinexact = get_inexact();
- #endif
- dval(&rv) = tens[k - 9] * dval(&rv) + z;
- }
- bd0 = 0;
- if (nd <= DBL_DIG
- #ifndef RND_PRODQUOT
- #ifndef Honor_FLT_ROUNDS
- && Flt_Rounds == 1
- #endif
- #endif
- ) {
- if (!e)
- goto ret;
- #ifndef ROUND_BIASED_without_Round_Up
- if (e > 0) {
- if (e <= Ten_pmax) {
- #ifdef VAX
- goto vax_ovfl_check;
- #else
- #ifdef Honor_FLT_ROUNDS
- /* round correctly FLT_ROUNDS = 2 or 3 */
- if (sign) {
- rv.d = -rv.d;
- sign = 0;
- }
- #endif
- /* rv = */ rounded_product(dval(&rv), tens[e]);
- goto ret;
- #endif
- }
- i = DBL_DIG - nd;
- if (e <= Ten_pmax + i) {
- /* A fancier test would sometimes let us do
- * this for larger i values.
- */
- #ifdef Honor_FLT_ROUNDS
- /* round correctly FLT_ROUNDS = 2 or 3 */
- if (sign) {
- rv.d = -rv.d;
- sign = 0;
- }
- #endif
- e -= i;
- dval(&rv) *= tens[i];
- #ifdef VAX
- /* VAX exponent range is so narrow we must
- * worry about overflow here...
- */
- vax_ovfl_check:
- word0(&rv) -= P*Exp_msk1;
- /* rv = */ rounded_product(dval(&rv), tens[e]);
- if ((word0(&rv) & Exp_mask)
- > Exp_msk1*(DBL_MAX_EXP+Bias-1-P))
- goto ovfl;
- word0(&rv) += P*Exp_msk1;
- #else
- /* rv = */ rounded_product(dval(&rv), tens[e]);
- #endif
- goto ret;
- }
- }
- #ifndef Inaccurate_Divide
- else if (e >= -Ten_pmax) {
- #ifdef Honor_FLT_ROUNDS
- /* round correctly FLT_ROUNDS = 2 or 3 */
- if (sign) {
- rv.d = -rv.d;
- sign = 0;
- }
- #endif
- /* rv = */ rounded_quotient(dval(&rv), tens[-e]);
- goto ret;
- }
- #endif
- #endif /* ROUND_BIASED_without_Round_Up */
- }
- e1 += nd - k;
- #ifdef IEEE_Arith
- #ifdef SET_INEXACT
- bc.inexact = 1;
- if (k <= DBL_DIG)
- oldinexact = get_inexact();
- #endif
- #ifdef Avoid_Underflow
- bc.scale = 0;
- #endif
- #ifdef Honor_FLT_ROUNDS
- if (bc.rounding >= 2) {
- if (sign)
- bc.rounding = bc.rounding == 2 ? 0 : 2;
- else
- if (bc.rounding != 2)
- bc.rounding = 0;
- }
- #endif
- #endif /*IEEE_Arith*/
- /* Get starting approximation = rv * 10**e1 */
- if (e1 > 0) {
- if ((i = e1 & 15))
- dval(&rv) *= tens[i];
- if (e1 &= ~15) {
- if (e1 > DBL_MAX_10_EXP) {
- ovfl:
- /* Can't trust HUGE_VAL */
- #ifdef IEEE_Arith
- #ifdef Honor_FLT_ROUNDS
- switch(bc.rounding) {
- case 0: /* toward 0 */
- case 3: /* toward -infinity */
- word0(&rv) = Big0;
- word1(&rv) = Big1;
- break;
- default:
- word0(&rv) = Exp_mask;
- word1(&rv) = 0;
- }
- #else /*Honor_FLT_ROUNDS*/
- word0(&rv) = Exp_mask;
- word1(&rv) = 0;
- #endif /*Honor_FLT_ROUNDS*/
- #ifdef SET_INEXACT
- /* set overflow bit */
- dval(&rv0) = 1e300;
- dval(&rv0) *= dval(&rv0);
- #endif
- #else /*IEEE_Arith*/
- word0(&rv) = Big0;
- word1(&rv) = Big1;
- #endif /*IEEE_Arith*/
- range_err:
- if (bd0) {
- Bfree(bb);
- Bfree(bd);
- Bfree(bs);
- Bfree(bd0);
- Bfree(delta);
- }
- #ifndef NO_ERRNO
- errno = ERANGE;
- #endif
- goto ret;
- }
- e1 >>= 4;
- for(j = 0; e1 > 1; j++, e1 >>= 1)
- if (e1 & 1)
- dval(&rv) *= bigtens[j];
- /* The last multiplication could overflow. */
- word0(&rv) -= P*Exp_msk1;
- dval(&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) */
- word0(&rv) = Big0;
- word1(&rv) = Big1;
- }
- else
- word0(&rv) += P*Exp_msk1;
- }
- }
- else if (e1 < 0) {
- e1 = -e1;
- if ((i = e1 & 15))
- dval(&rv) /= tens[i];
- if (e1 >>= 4) {
- if (e1 >= 1 << n_bigtens)
- goto undfl;
- #ifdef Avoid_Underflow
- if (e1 & Scale_Bit)
- bc.scale = 2*P;
- for(j = 0; e1 > 0; j++, e1 >>= 1)
- if (e1 & 1)
- dval(&rv) *= tinytens[j];
- if (bc.scale && (j = 2*P + 1 - ((word0(&rv) & Exp_mask)
- >> Exp_shift)) > 0) {
- /* scaled rv is denormal; clear j low bits */
- if (j >= 32) {
- if (j > 54)
- goto undfl;
- word1(&rv) = 0;
- if (j >= 53)
- word0(&rv) = (P+2)*Exp_msk1;
- else
- word0(&rv) &= 0xffffffff << (j-32);
- }
- else
- word1(&rv) &= 0xffffffff << j;
- }
- #else
- for(j = 0; e1 > 1; j++, e1 >>= 1)
- if (e1 & 1)
- dval(&rv) *= tinytens[j];
- /* The last multiplication could underflow. */
- dval(&rv0) = dval(&rv);
- dval(&rv) *= tinytens[j];
- if (!dval(&rv)) {
- dval(&rv) = 2.*dval(&rv0);
- dval(&rv) *= tinytens[j];
- #endif
- if (!dval(&rv)) {
- undfl:
- dval(&rv) = 0.;
- goto range_err;
- }
- #ifndef Avoid_Underflow
- word0(&rv) = Tiny0;
- 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 */
- bc.nd = nd - nz1;
- #ifndef NO_STRTOD_BIGCOMP
- bc.nd0 = nd0; /* Only needed if nd > strtod_diglim, but done here */
- /* to silence an erroneous warning about bc.nd0 */
- /* possibly not being initialized. */
- if (nd > strtod_diglim) {
- /* ASSERT(strtod_diglim >= 18); 18 == one more than the */
- /* minimum number of decimal digits to distinguish double values */
- /* in IEEE arithmetic. */
- i = j = 18;
- if (i > nd0)
- j += bc.dplen;
- for(;;) {
- if (--j < bc.dp1 && j >= bc.dp0)
- j = bc.dp0 - 1;
- if (s0[j] != '0')
- break;
- --i;
- }
- e += nd - i;
- nd = i;
- if (nd0 > nd)
- nd0 = nd;
- if (nd < 9) { /* must recompute y */
- y = 0;
- for(i = 0; i < nd0; ++i)
- y = 10*y + s0[i] - '0';
- for(j = bc.dp1; i < nd; ++i)
- y = 10*y + s0[j++] - '0';
- }
- }
- #endif
- bd0 = s2b(s0, nd0, nd, y, bc.dplen);
- for(;;) {
- bd = Balloc(bd0->k);
- Bcopy(bd, bd0);
- bb = d2b(&rv, &bbe, &bbbits); /* rv = bb * 2^bbe */
- bs = i2b(1);
- 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 Honor_FLT_ROUNDS
- if (bc.rounding != 1)
- bs2++;
- #endif
- #ifdef Avoid_Underflow
- Lsb = LSB;
- Lsb1 = 0;
- j = bbe - bc.scale;
- i = j + bbbits - 1; /* logb(rv) */
- j = P + 1 - bbbits;
- if (i < Emin) { /* denormal */
- i = Emin - i;
- j -= i;
- if (i < 32)
- Lsb <<= i;
- else if (i < 52)
- Lsb1 = Lsb << (i-32);
- else
- Lsb1 = Exp_mask;
- }
- #else /*Avoid_Underflow*/
- #ifdef Sudden_Underflow
- #ifdef IBM
- j = 1 + 4*P - 3 - bbbits + ((bbe + bbbits - 1) & 3);
- #else
- j = P + 1 - bbbits;
- #endif
- #else /*Sudden_Underflow*/
- j = bbe;
- i = j + bbbits - 1; /* logb(rv) */
- if (i < Emin) /* denormal */
- j += P - Emin;
- else
- j = P + 1 - bbbits;
- #endif /*Sudden_Underflow*/
- #endif /*Avoid_Underflow*/
- bb2 += j;
- bd2 += j;
- #ifdef Avoid_Underflow
- bd2 += bc.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);
- bb1 = mult(bs, bb);
- Bfree(bb);
- bb = bb1;
- }
- if (bb2 > 0)
- bb = lshift(bb, bb2);
- if (bd5 > 0)
- bd = pow5mult(bd, bd5);
- if (bd2 > 0)
- bd = lshift(bd, bd2);
- if (bs2 > 0)
- bs = lshift(bs, bs2);
- delta = diff(bb, bd);
- bc.dsign = delta->sign;
- delta->sign = 0;
- i = cmp(delta, bs);
- #ifndef NO_STRTOD_BIGCOMP /*{*/
- if (bc.nd > nd && i <= 0) {
- if (bc.dsign) {
- /* Must use bigcomp(). */
- req_bigcomp = 1;
- break;
- }
- #ifdef Honor_FLT_ROUNDS
- if (bc.rounding != 1) {
- if (i < 0) {
- req_bigcomp = 1;
- break;
- }
- }
- else
- #endif
- i = -1; /* Discarded digits make delta smaller. */
- }
- #endif /*}*/
- #ifdef Honor_FLT_ROUNDS /*{*/
- if (bc.rounding != 1) {
- if (i < 0) {
- /* Error is less than an ulp */
- if (!delta->x[0] && delta->wds <= 1) {
- /* exact */
- #ifdef SET_INEXACT
- bc.inexact = 0;
- #endif
- break;
- }
- if (bc.rounding) {
- if (bc.dsign) {
- adj.d = 1.;
- goto apply_adj;
- }
- }
- else if (!bc.dsign) {
- adj.d = -1.;
- if (!word1(&rv)
- && !(word0(&rv) & Frac_mask)) {
- y = word0(&rv) & Exp_mask;
- #ifdef Avoid_Underflow
- if (!bc.scale || y > 2*P*Exp_msk1)
- #else
- if (y)
- #endif
- {
- delta = lshift(delta,Log2P);
- if (cmp(delta, bs) <= 0)
- adj.d = -0.5;
- }
- }
- apply_adj:
- #ifdef Avoid_Underflow /*{*/
- if (bc.scale && (y = word0(&rv) & Exp_mask)
- <= 2*P*Exp_msk1)
- word0(&adj) += (2*P+1)*Exp_msk1 - y;
- #else
- #ifdef Sudden_Underflow
- if ((word0(&rv) & Exp_mask) <=
- P*Exp_msk1) {
- word0(&rv) += P*Exp_msk1;
- dval(&rv) += adj.d*ulp(dval(&rv));
- word0(&rv) -= P*Exp_msk1;
- }
- else
- #endif /*Sudden_Underflow*/
- #endif /*Avoid_Underflow}*/
- dval(&rv) += adj.d*ulp(&rv);
- }
- break;
- }
- adj.d = ratio(delta, bs);
- if (adj.d < 1.)
- adj.d = 1.;
- if (adj.d <= 0x7ffffffe) {
- /* adj = rounding ? ceil(adj) : floor(adj); */
- y = adj.d;
- if (y != adj.d) {
- if (!((bc.rounding>>1) ^ bc.dsign))
- y++;
- adj.d = y;
- }
- }
- #ifdef Avoid_Underflow /*{*/
- if (bc.scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
- word0(&adj) += (2*P+1)*Exp_msk1 - y;
- #else
- #ifdef Sudden_Underflow
- if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
- word0(&rv) += P*Exp_msk1;
- adj.d *= ulp(dval(&rv));
- if (bc.dsign)
- dval(&rv) += adj.d;
- else
- dval(&rv) -= adj.d;
- word0(&rv) -= P*Exp_msk1;
- goto cont;
- }
- #endif /*Sudden_Underflow*/
- #endif /*Avoid_Underflow}*/
- adj.d *= ulp(&rv);
- if (bc.dsign) {
- if (word0(&rv) == Big0 && word1(&rv) == Big1)
- goto ovfl;
- dval(&rv) += adj.d;
- }
- else
- dval(&rv) -= adj.d;
- goto cont;
- }
- #endif /*}Honor_FLT_ROUNDS*/
- if (i < 0) {
- /* Error is less than half an ulp -- check for
- * special case of mantissa a power of two.
- */
- if (bc.dsign || word1(&rv) || word0(&rv) & Bndry_mask
- #ifdef IEEE_Arith /*{*/
- #ifdef Avoid_Underflow
- || (word0(&rv) & Exp_mask) <= (2*P+1)*Exp_msk1
- #else
- || (word0(&rv) & Exp_mask) <= Exp_msk1
- #endif
- #endif /*}*/
- ) {
- #ifdef SET_INEXACT
- if (!delta->x[0] && delta->wds <= 1)
- bc.inexact = 0;
- #endif
- break;
- }
- if (!delta->x[0] && delta->wds <= 1) {
- /* exact result */
- #ifdef SET_INEXACT
- bc.inexact = 0;
- #endif
- break;
- }
- delta = lshift(delta,Log2P);
- if (cmp(delta, bs) > 0)
- goto drop_down;
- break;
- }
- if (i == 0) {
- /* exactly half-way between */
- if (bc.dsign) {
- if ((word0(&rv) & Bndry_mask1) == Bndry_mask1
- && word1(&rv) == (
- #ifdef Avoid_Underflow
- (bc.scale && (y = word0(&rv) & Exp_mask) <= 2*P*Exp_msk1)
- ? (0xffffffff & (0xffffffff << (2*P+1-(y>>Exp_shift)))) :
- #endif
- 0xffffffff)) {
- /*boundary case -- increment exponent*/
- if (word0(&rv) == Big0 && word1(&rv) == Big1)
- goto ovfl;
- word0(&rv) = (word0(&rv) & Exp_mask)
- + Exp_msk1
- #ifdef IBM
- | Exp_msk1 >> 4
- #endif
- ;
- word1(&rv) = 0;
- #ifdef Avoid_Underflow
- bc.dsign = 0;
- #endif
- break;
- }
- }
- else if (!(word0(&rv) & Bndry_mask) && !word1(&rv)) {
- drop_down:
- /* boundary case -- decrement exponent */
- #ifdef Sudden_Underflow /*{{*/
- L = word0(&rv) & Exp_mask;
- #ifdef IBM
- if (L < Exp_msk1)
- #else
- #ifdef Avoid_Underflow
- if (L <= (bc.scale ? (2*P+1)*Exp_msk1 : Exp_msk1))
- #else
- if (L <= Exp_msk1)
- #endif /*Avoid_Underflow*/
- #endif /*IBM*/
- {
- if (bc.nd >nd) {
- bc.uflchk = 1;
- break;
- }
- goto undfl;
- }
- L -= Exp_msk1;
- #else /*Sudden_Underflow}{*/
- #ifdef Avoid_Underflow
- if (bc.scale) {
- L = word0(&rv) & Exp_mask;
- if (L <= (2*P+1)*Exp_msk1) {
- if (L > (P+2)*Exp_msk1)
- /* round even ==> */
- /* accept rv */
- break;
- /* rv = smallest denormal */
- if (bc.nd >nd) {
- bc.uflchk = 1;
- break;
- }
- goto undfl;
- }
- }
- #endif /*Avoid_Underflow*/
- L = (word0(&rv) & Exp_mask) - Exp_msk1;
- #endif /*Sudden_Underflow}}*/
- word0(&rv) = L | Bndry_mask1;
- word1(&rv) = 0xffffffff;
- #ifdef IBM
- goto cont;
- #else
- #ifndef NO_STRTOD_BIGCOMP
- if (bc.nd > nd)
- goto cont;
- #endif
- break;
- #endif
- }
- #ifndef ROUND_BIASED
- #ifdef Avoid_Underflow
- if (Lsb1) {
- if (!(word0(&rv) & Lsb1))
- break;
- }
- else if (!(word1(&rv) & Lsb))
- break;
- #else
- if (!(word1(&rv) & LSB))
- break;
- #endif
- #endif
- if (bc.dsign)
- #ifdef Avoid_Underflow
- dval(&rv) += sulp(&rv, &bc);
- #else
- dval(&rv) += ulp(&rv);
- #endif
- #ifndef ROUND_BIASED
- else {
- #ifdef Avoid_Underflow
- dval(&rv) -= sulp(&rv, &bc);
- #else
- dval(&rv) -= ulp(&rv);
- #endif
- #ifndef Sudden_Underflow
- if (!dval(&rv)) {
- if (bc.nd >nd) {
- bc.uflchk = 1;
- break;
- }
- goto undfl;
- }
- #endif
- }
- #ifdef Avoid_Underflow
- bc.dsign = 1 - bc.dsign;
- #endif
- #endif
- break;
- }
- if ((aadj = ratio(delta, bs)) <= 2.) {
- if (bc.dsign)
- aadj = aadj1 = 1.;
- else if (word1(&rv) || word0(&rv) & Bndry_mask) {
- #ifndef Sudden_Underflow
- if (word1(&rv) == Tiny1 && !word0(&rv)) {
- if (bc.nd >nd) {
- bc.uflchk = 1;
- break;
- }
- 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 = bc.dsign ? aadj : -aadj;
- #ifdef Check_FLT_ROUNDS
- switch(bc.rounding) {
- 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 /*Check_FLT_ROUNDS*/
- }
- y = word0(&rv) & Exp_mask;
- /* Check for overflow */
- if (y == Exp_msk1*(DBL_MAX_EXP+Bias-1)) {
- dval(&rv0) = dval(&rv);
- word0(&rv) -= P*Exp_msk1;
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- if ((word0(&rv) & Exp_mask) >=
- Exp_msk1*(DBL_MAX_EXP+Bias-P)) {
- if (word0(&rv0) == Big0 && word1(&rv0) == Big1)
- goto ovfl;
- word0(&rv) = Big0;
- word1(&rv) = Big1;
- goto cont;
- }
- else
- word0(&rv) += P*Exp_msk1;
- }
- else {
- #ifdef Avoid_Underflow
- if (bc.scale && y <= 2*P*Exp_msk1) {
- if (aadj <= 0x7fffffff) {
- if ((z = aadj) <= 0)
- z = 1;
- aadj = z;
- aadj1 = bc.dsign ? aadj : -aadj;
- }
- dval(&aadj2) = aadj1;
- word0(&aadj2) += (2*P+1)*Exp_msk1 - y;
- aadj1 = dval(&aadj2);
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- if (rv.d == 0.)
- #ifdef NO_STRTOD_BIGCOMP
- goto undfl;
- #else
- {
- if (bc.nd > nd)
- bc.dsign = 1;
- break;
- }
- #endif
- }
- else {
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- }
- #else
- #ifdef Sudden_Underflow
- if ((word0(&rv) & Exp_mask) <= P*Exp_msk1) {
- dval(&rv0) = dval(&rv);
- word0(&rv) += P*Exp_msk1;
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- #ifdef IBM
- if ((word0(&rv) & Exp_mask) < P*Exp_msk1)
- #else
- if ((word0(&rv) & Exp_mask) <= P*Exp_msk1)
- #endif
- {
- if (word0(&rv0) == Tiny0
- && word1(&rv0) == Tiny1) {
- if (bc.nd >nd) {
- bc.uflchk = 1;
- break;
- }
- goto undfl;
- }
- word0(&rv) = Tiny0;
- word1(&rv) = Tiny1;
- goto cont;
- }
- else
- word0(&rv) -= P*Exp_msk1;
- }
- else {
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- }
- #else /*Sudden_Underflow*/
- /* 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 .
- */
- if (y <= (P-1)*Exp_msk1 && aadj > 1.) {
- aadj1 = (double)(int)(aadj + 0.5);
- if (!bc.dsign)
- aadj1 = -aadj1;
- }
- adj.d = aadj1 * ulp(&rv);
- dval(&rv) += adj.d;
- #endif /*Sudden_Underflow*/
- #endif /*Avoid_Underflow*/
- }
- z = word0(&rv) & Exp_mask;
- #ifndef SET_INEXACT
- if (bc.nd == nd) {
- #ifdef Avoid_Underflow
- if (!bc.scale)
- #endif
- if (y == z) {
- /* Can we stop now? */
- L = (Long)aadj;
- aadj -= L;
- /* The tolerances below are conservative. */
- if (bc.dsign || word1(&rv) || word0(&rv) & Bndry_mask) {
- if (aadj < .4999999 || aadj > .5000001)
- break;
- }
- else if (aadj < .4999999/FLT_RADIX)
- break;
- }
- }
- #endif
- cont:
- Bfree(bb);
- Bfree(bd);
- Bfree(bs);
- Bfree(delta);
- }
- Bfree(bb);
- Bfree(bd);
- Bfree(bs);
- Bfree(bd0);
- Bfree(delta);
- #ifndef NO_STRTOD_BIGCOMP
- if (req_bigcomp) {
- bd0 = 0;
- bc.e0 += nz1;
- bigcomp(&rv, s0, &bc);
- y = word0(&rv) & Exp_mask;
- if (y == Exp_mask)
- goto ovfl;
- if (y == 0 && rv.d == 0.)
- goto undfl;
- }
- #endif
- #ifdef SET_INEXACT
- if (bc.inexact) {
- if (!oldinexact) {
- word0(&rv0) = Exp_1 + (70 << Exp_shift);
- word1(&rv0) = 0;
- dval(&rv0) += 1.;
- }
- }
- else if (!oldinexact)
- clear_inexact();
- #endif
- #ifdef Avoid_Underflow
- if (bc.scale) {
- word0(&rv0) = Exp_1 - 2*P*Exp_msk1;
- word1(&rv0) = 0;
- dval(&rv) *= dval(&rv0);
- #ifndef NO_ERRNO
- /* try to avoid the bug of testing an 8087 register value */
- #ifdef IEEE_Arith
- if (!(word0(&rv) & Exp_mask))
- #else
- if (word0(&rv) == 0 && word1(&rv) == 0)
- #endif
- errno = ERANGE;
- #endif
- }
- #endif /* Avoid_Underflow */
- #ifdef SET_INEXACT
- if (bc.inexact && !(word0(&rv) & Exp_mask)) {
- /* set underflow bit */
- dval(&rv0) = 1e-300;
- dval(&rv0) *= dval(&rv0);
- }
- #endif
- ret:
- if (se)
- *se = (char *)s;
- return sign ? -dval(&rv) : dval(&rv);
- }
- #ifndef MULTIPLE_THREADS
- static char *dtoa_result;
- #endif
- static char *
- #ifdef KR_headers
- rv_alloc(i) int i;
- #else
- rv_alloc(int i)
- #endif
- {
- int j, k, *r;
- j = sizeof(ULong);
- for(k = 0;
- sizeof(Bigint) - sizeof(ULong) - sizeof(int) + j <= i;
- j <<= 1)
- k++;
- r = (int*)Balloc(k);
- *r = k;
- return
- #ifndef MULTIPLE_THREADS
- dtoa_result =
- #endif
- (char *)(r+1);
- }
- static char *
- #ifdef KR_headers
- nrv_alloc(s, rve, n) char *s, **rve; int n;
- #else
- nrv_alloc(const char *s, char **rve, int n)
- #endif
- {
- char *rv, *t;
- t = rv = rv_alloc(n);
- while((*t = *s++)) t++;
- if (rve)
- *rve = t;
- return rv;
- }
- /* freedtoa(s) must be used to free values s returned by dtoa
- * when MULTIPLE_THREADS is #defined. It should be used in all cases,
- * but for consistency with earlier versions of dtoa, it is optional
- * when MULTIPLE_THREADS is not defined.
- */
- void
- #ifdef KR_headers
- freedtoa(s) char *s;
- #else
- freedtoa(char *s)
- #endif
- {
- Bigint *b = (Bigint *)((int *)s - 1);
- b->maxwds = 1 << (b->k = *(int*)b);
- Bfree(b);
- #ifndef MULTIPLE_THREADS
- if (s == dtoa_result)
- dtoa_result = 0;
- #endif
- }
- /* 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. 112-126].
- *
- * 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.
- */
- char *
- dtoa
- #ifdef KR_headers
- (dd, mode, ndigits, decpt, sign, rve)
- double dd; int mode, ndigits, *decpt, *sign; char **rve;
- #else
- (double dd, int mode, int ndigits, int *decpt, int *sign, char **rve)
- #endif
- {
- /* 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.
- 4,5 ==> similar to 2 and 3, respectively, but (in
- round-nearest mode) with the tests of mode 0 to
- possibly return a shorter string that rounds to d.
- With IEEE arithmetic and compilation with
- -DHonor_FLT_ROUNDS, modes 4 and 5 behave the same
- as modes 2 and 3 when FLT_ROUNDS != 1.
- 6-9 ==> Debugging modes similar to mode - 4: 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 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
- int denorm;
- ULong x;
- #endif
- Bigint *b, *b1, *delta, *mlo, *mhi, *S;
- U d2, eps, u;
- double ds;
- char *s, *s0;
- #ifndef No_leftright
- #ifdef IEEE_Arith
- U eps1;
- #endif
- #endif
- #ifdef SET_INEXACT
- int inexact, oldinexact;
- #endif
- #ifdef Honor_FLT_ROUNDS /*{*/
- int Rounding;
- #ifdef Trust_FLT_ROUNDS /*{{ only define this if FLT_ROUNDS really works! */
- Rounding = Flt_Rounds;
- #else /*}{*/
- Rounding = 1;
- switch(fegetround()) {
- case FE_TOWARDZERO: Rounding = 0; break;
- case FE_UPWARD: Rounding = 2; break;
- case FE_DOWNWARD: Rounding = 3;
- }
- #endif /*}}*/
- #endif /*}*/
- #ifndef MULTIPLE_THREADS
- if (dtoa_result) {
- freedtoa(dtoa_result);
- dtoa_result = 0;
- }
- #endif
- u.d = dd;
- if (word0(&u) & Sign_bit) {
- /* set sign for everything, including 0's and NaNs */
- *sign = 1;
- word0(&u) &= ~Sign_bit; /* clear sign bit */
- }
- else
- *sign = 0;
- #if defined(IEEE_Arith) + defined(VAX)
- #ifdef IEEE_Arith
- if ((word0(&u) & Exp_mask) == Exp_mask)
- #else
- if (word0(&u) == 0x8000)
- #endif
- {
- /* Infinity or NaN */
- *decpt = 9999;
- #ifdef IEEE_Arith
- if (!word1(&u) && !(word0(&u) & 0xfffff))
- return nrv_alloc("Infinity", rve, 8);
- #endif
- return nrv_alloc("NaN", rve, 3);
- }
- #endif
- #ifdef IBM
- dval(&u) += 0; /* normalize */
- #endif
- if (!dval(&u)) {
- *decpt = 1;
- return nrv_alloc("0", rve, 1);
- }
- #ifdef SET_INEXACT
- try_quick = oldinexact = get_inexact();
- inexact = 1;
- #endif
- #ifdef Honor_FLT_ROUNDS
- if (Rounding >= 2) {
- if (*sign)
- Rounding = Rounding == 2 ? 0 : 2;
- else
- if (Rounding != 2)
- Rounding = 0;
- }
- #endif
- b = d2b(&u, &be, &bbits);
- #ifdef Sudden_Underflow
- i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1));
- #else
- if ((i = (int)(word0(&u) >> Exp_shift1 & (Exp_mask>>Exp_shift1)))) {
- #endif
- dval(&d2) = dval(&u);
- word0(&d2) &= Frac_mask1;
- word0(&d2) |= Exp_11;
- #ifdef IBM
- if (j = 11 - hi0bits(word0(&d2) & Frac_mask))
- dval(&d2) /= 1 << j;
- #endif
- /* 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;
- #ifdef IBM
- i <<= 2;
- i += j;
- #endif
- #ifndef Sudden_Underflow
- denorm = 0;
- }
- else {
- /* d is denormalized */
- i = bbits + be + (Bias + (P-1) - 1);
- x = i > 32 ? word0(&u) << (64 - i) | word1(&u) >> (i - 32)
- : word1(&u) << (32 - i);
- dval(&d2) = x;
- word0(&d2) -= 31*Exp_msk1; /* adjust exponent */
- i -= (Bias + (P-1) - 1) + 1;
- denorm = 1;
- }
- #endif
- ds = (dval(&d2)-1.5)*0.289529654602168 + 0.1760912590558 + i*0.301029995663981;
- k = (int)ds;
- if (ds < 0. && ds != k)
- k--; /* want k = floor(ds) */
- k_check = 1;
- if (k >= 0 && k <= Ten_pmax) {
- if (dval(&u) < tens[k])
- k--;
- k_check = 0;
- }
- j = bbits - i - 1;
- 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;
- }
- if (mode < 0 || mode > 9)
- mode = 0;
- #ifndef SET_INEXACT
- #ifdef Check_FLT_ROUNDS
- try_quick = Rounding == 1;
- #else
- try_quick = 1;
- #endif
- #endif /*SET_INEXACT*/
- if (mode > 5) {
- mode -= 4;
- try_quick = 0;
- }
- leftright = 1;
- ilim = ilim1 = -1; /* Values for cases 0 and 1; done here to */
- /* silence erroneous "gcc -Wall" warning. */
- switch(mode) {
- case 0:
- case 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;
- }
- s = s0 = rv_alloc(i);
- #ifdef Honor_FLT_ROUNDS
- if (mode > 1 && Rounding != 1)
- leftright = 0;
- #endif
- if (ilim >= 0 && ilim <= Quick_max && try_quick) {
- /* Try to get by with floating-point arithmetic. */
- i = 0;
- dval(&d2) = dval(&u);
- k0 = k;
- ilim0 = ilim;
- ieps = 2; /* conservative */
- if (k > 0) {
- ds = tens[k&0xf];
- j = k >> 4;
- if (j & Bletch) {
- /* prevent overflows */
- j &= Bletch - 1;
- dval(&u) /= bigtens[n_bigtens-1];
- ieps++;
- }
- for(; j; j >>= 1, i++)
- if (j & 1) {
- ieps++;
- ds *= bigtens[i];
- }
- dval(&u) /= ds;
- }
- else if ((j1 = -k)) {
- dval(&u) *= tens[j1 & 0xf];
- for(j = j1 >> 4; j; j >>= 1, i++)
- if (j & 1) {
- ieps++;
- dval(&u) *= bigtens[i];
- }
- }
- if (k_check && dval(&u) < 1. && ilim > 0) {
- if (ilim1 <= 0)
- goto fast_failed;
- ilim = ilim1;
- k--;
- dval(&u) *= 10.;
- ieps++;
- }
- dval(&eps) = ieps*dval(&u) + 7.;
- word0(&eps) -= (P-1)*Exp_msk1;
- if (ilim == 0) {
- S = mhi = 0;
- dval(&u) -= 5.;
- if (dval(&u) > dval(&eps))
- goto one_digit;
- if (dval(&u) < -dval(&eps))
- goto no_digits;
- goto fast_failed;
- }
- #ifndef No_leftright
- if (leftright) {
- /* Use Steele & White method of only
- * generating digits needed.
- */
- dval(&eps) = 0.5/tens[ilim-1] - dval(&eps);
- #ifdef IEEE_Arith
- if (k0 < 0 && j1 >= 307) {
- eps1.d = 1.01e256; /* 1.01 allows roundoff in the next few lines */
- word0(&eps1) -= Exp_msk1 * (Bias+P-1);
- dval(&eps1) *= tens[j1 & 0xf];
- for(i = 0, j = (j1-256) >> 4; j; j >>= 1, i++)
- if (j & 1)
- dval(&eps1) *= bigtens[i];
- if (eps.d < eps1.d)
- eps.d = eps1.d;
- }
- #endif
- for(i = 0;;) {
- L = dval(&u);
- dval(&u) -= L;
- *s++ = '0' + (int)L;
- if (1. - dval(&u) < dval(&eps))
- goto bump_up;
- if (dval(&u) < dval(&eps))
- goto ret1;
- if (++i >= ilim)
- break;
- dval(&eps) *= 10.;
- dval(&u) *= 10.;
- }
- }
- else {
- #endif
- /* Generate ilim digits, then fix them up. */
- dval(&eps) *= tens[ilim-1];
- for(i = 1;; i++, dval(&u) *= 10.) {
- L = (Long)(dval(&u));
- if (!(dval(&u) -= L))
- ilim = i;
- *s++ = '0' + (int)L;
- if (i == ilim) {
- if (dval(&u) > 0.5 + dval(&eps))
- goto bump_up;
- else if (dval(&u) < 0.5 - dval(&eps)) {
- while(*--s == '0');
- s++;
- goto ret1;
- }
- break;
- }
- }
- #ifndef No_leftright
- }
- #endif
- fast_failed:
- s = s0;
- dval(&u) = dval(&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 || dval(&u) <= 5*ds)
- goto no_digits;
- goto one_digit;
- }
- for(i = 1;; i++, dval(&u) *= 10.) {
- L = (Long)(dval(&u) / ds);
- dval(&u) -= L*ds;
- #ifdef Check_FLT_ROUNDS
- /* If FLT_ROUNDS == 2, L will usually be high by 1 */
- if (dval(&u) < 0) {
- L--;
- dval(&u) += ds;
- }
- #endif
- *s++ = '0' + (int)L;
- if (!dval(&u)) {
- #ifdef SET_INEXACT
- inexact = 0;
- #endif
- break;
- }
- if (i == ilim) {
- #ifdef Honor_FLT_ROUNDS
- if (mode > 1)
- switch(Rounding) {
- case 0: goto ret1;
- case 2: goto bump_up;
- }
- #endif
- dval(&u) += dval(&u);
- #ifdef ROUND_BIASED
- if (dval(&u) >= ds)
- #else
- if (dval(&u) > ds || (dval(&u) == ds && L & 1))
- #endif
- {
- bump_up:
- while(*--s == '9')
- if (s == s0) {
- k++;
- *s = '0';
- break;
- }
- ++*s++;
- }
- break;
- }
- }
- goto ret1;
- }
- m2 = b2;
- m5 = b5;
- mhi = mlo = 0;
- if (leftright) {
- i =
- #ifndef Sudden_Underflow
- denorm ? be + (Bias + (P-1) - 1 + 1) :
- #endif
- #ifdef IBM
- 1 + 4*P - 3 - bbits + ((bbits + be - 1) & 3);
- #else
- 1 + P - bbits;
- #endif
- b2 += i;
- s2 += i;
- mhi = i2b(1);
- }
- if (m2 > 0 && s2 > 0) {
- i = m2 < s2 ? m2 : s2;
- b2 -= i;
- m2 -= i;
- s2 -= i;
- }
- if (b5 > 0) {
- if (leftright) {
- if (m5 > 0) {
- mhi = pow5mult(mhi, m5);
- b1 = mult(mhi, b);
- Bfree(b);
- b = b1;
- }
- if ((j = b5 - m5))
- b = pow5mult(b, j);
- }
- else
- b = pow5mult(b, b5);
- }
- S = i2b(1);
- if (s5 > 0)
- S = pow5mult(S, s5);
- /* Check for special case that d is a normalized power of 2. */
- spec_case = 0;
- if ((mode < 2 || leftright)
- #ifdef Honor_FLT_ROUNDS
- && Rounding == 1
- #endif
- ) {
- if (!word1(&u) && !(word0(&u) & Bndry_mask)
- #ifndef Sudden_Underflow
- && word0(&u) & (Exp_mask & ~Exp_msk1)
- #endif
- ) {
- /* The special case */
- 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.
- */
- i = dshift(S, s2);
- b2 += i;
- m2 += i;
- s2 += i;
- if (b2 > 0)
- b = lshift(b, b2);
- if (s2 > 0)
- S = lshift(S, s2);
- if (k_check) {
- if (cmp(b,S) < 0) {
- k--;
- b = multadd(b, 10, 0); /* we botched the k estimate */
- if (leftright)
- mhi = multadd(mhi, 10, 0);
- ilim = ilim1;
- }
- }
- if (ilim <= 0 && (mode == 3 || mode == 5)) {
- if (ilim < 0 || cmp(b,S = multadd(S,5,0)) <= 0) {
- /* no digits, fcvt style */
- no_digits:
- k = -1 - ndigits;
- goto ret;
- }
- one_digit:
- *s++ = '1';
- k++;
- goto ret;
- }
- if (leftright) {
- if (m2 > 0)
- mhi = lshift(mhi, m2);
- /* Compute mlo -- check for special case
- * that d is a normalized power of 2.
- */
- mlo = mhi;
- if (spec_case) {
- mhi = Balloc(mhi->k);
- Bcopy(mhi, mlo);
- mhi = lshift(mhi, Log2P);
- }
- 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);
- delta = diff(S, mhi);
- j1 = delta->sign ? 1 : cmp(b, delta);
- Bfree(delta);
- #ifndef ROUND_BIASED
- if (j1 == 0 && mode != 1 && !(word1(&u) & 1)
- #ifdef Honor_FLT_ROUNDS
- && Rounding >= 1
- #endif
- ) {
- if (dig == '9')
- goto round_9_up;
- if (j > 0)
- dig++;
- #ifdef SET_INEXACT
- else if (!b->x[0] && b->wds <= 1)
- inexact = 0;
- #endif
- *s++ = dig;
- goto ret;
- }
- #endif
- if (j < 0 || (j == 0 && mode != 1
- #ifndef ROUND_BIASED
- && !(word1(&u) & 1)
- #endif
- )) {
- if (!b->x[0] && b->wds <= 1) {
- #ifdef SET_INEXACT
- inexact = 0;
- #endif
- goto accept_dig;
- }
- #ifdef Honor_FLT_ROUNDS
- if (mode > 1)
- switch(Rounding) {
- case 0: goto accept_dig;
- case 2: goto keep_dig;
- }
- #endif /*Honor_FLT_ROUNDS*/
- if (j1 > 0) {
- b = lshift(b, 1);
- j1 = cmp(b, S);
- #ifdef ROUND_BIASED
- if (j1 >= 0 /*)*/
- #else
- if ((j1 > 0 || (j1 == 0 && dig & 1))
- #endif
- && dig++ == '9')
- goto round_9_up;
- }
- accept_dig:
- *s++ = dig;
- goto ret;
- }
- if (j1 > 0) {
- #ifdef Honor_FLT_ROUNDS
- if (!Rounding)
- goto accept_dig;
- #endif
- if (dig == '9') { /* possible if i == 1 */
- round_9_up:
- *s++ = '9';
- goto roundoff;
- }
- *s++ = dig + 1;
- goto ret;
- }
- #ifdef Honor_FLT_ROUNDS
- keep_dig:
- #endif
- *s++ = dig;
- if (i == ilim)
- break;
- b = multadd(b, 10, 0);
- if (mlo == mhi)
- mlo = mhi = multadd(mhi, 10, 0);
- else {
- mlo = multadd(mlo, 10, 0);
- mhi = multadd(mhi, 10, 0);
- }
- }
- }
- else
- for(i = 1;; i++) {
- *s++ = dig = quorem(b,S) + '0';
- if (!b->x[0] && b->wds <= 1) {
- #ifdef SET_INEXACT
- inexact = 0;
- #endif
- goto ret;
- }
- if (i >= ilim)
- break;
- b = multadd(b, 10, 0);
- }
- /* Round off last digit */
- #ifdef Honor_FLT_ROUNDS
- switch(Rounding) {
- case 0: goto trimzeros;
- case 2: goto roundoff;
- }
- #endif
- b = lshift(b, 1);
- j = cmp(b, S);
- #ifdef ROUND_BIASED
- if (j >= 0)
- #else
- if (j > 0 || (j == 0 && dig & 1))
- #endif
- {
- roundoff:
- while(*--s == '9')
- if (s == s0) {
- k++;
- *s++ = '1';
- goto ret;
- }
- ++*s++;
- }
- else {
- #ifdef Honor_FLT_ROUNDS
- trimzeros:
- #endif
- while(*--s == '0');
- s++;
- }
- ret:
- Bfree(S);
- if (mhi) {
- if (mlo && mlo != mhi)
- Bfree(mlo);
- Bfree(mhi);
- }
- ret1:
- #ifdef SET_INEXACT
- if (inexact) {
- if (!oldinexact) {
- word0(&u) = Exp_1 + (70 << Exp_shift);
- word1(&u) = 0;
- dval(&u) += 1.;
- }
- }
- else if (!oldinexact)
- clear_inexact();
- #endif
- Bfree(b);
- *s = 0;
- *decpt = k + 1;
- if (rve)
- *rve = s;
- return s0;
- }
- #ifdef __cplusplus
- }
- #endif
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