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update from main archive 970304
1997-03-04 04:31 Ulrich Drepper <drepper@cygnus.com> * Makerules: Add rules to handle versioning. * config.h.in (DO_VERSIONING): New macro. * config.make.in (versioning): New variable. * configure.in: Add checks for .symver directive in gas and --version-script option to ld. Define DO_VERSIONING and versioning if appropriate. * math/Makefile (routines): Add s_signbit, s_fpclassify, s_fmax, s_fmin, and s_fdim. * math/math.h: Define ISO C 9X constants, macros and functions. * math/mathcalls.h: Likewise. * sysdeps/libm-ieee754/s_fdim.c: New file. * sysdeps/libm-ieee754/s_fdimf.c: New file. * sysdeps/libm-ieee754/s_fdiml.c: New file. * sysdeps/libm-ieee754/s_fmax.c: New file. * sysdeps/libm-ieee754/s_fmaxf.c: New file. * sysdeps/libm-ieee754/s_fmaxl.c: New file. * sysdeps/libm-ieee754/s_fmin.c: New file. * sysdeps/libm-ieee754/s_fminf.c: New file. * sysdeps/libm-ieee754/s_fminl.c: New file. * sysdeps/libm-ieee754/s_fpclassify.c: New file. * sysdeps/libm-ieee754/s_fpclassifyf.c: New file. * sysdeps/libm-ieee754/s_fpclassifyl.c: New file. * sysdeps/libm-ieee754/s_signbit.c: New file. * sysdeps/libm-ieee754/s_signbitf.c: New file. * sysdeps/libm-ieee754/s_signbitl.c: New file. * stdio-common/printf_fphex.c: Correct printing of decimal point character. Simplify conversion of mantissa to string. * stdio-common/vfscanf.c: Handle %A format. Optimize termination of floating-point scanning. * stdio-common/tstscanf.c (main): Add new test to scanf to test scanning float values with given width. * stdlib/strtod.c: Add handling of floating-point numbers in hexadecimal notation. * stdlib/stdlib.h: Use __USE_ISOC9X feature macro for new long long functions. Pretty print #if directives. * string/string.h: Pretty print #if directives. * sysdeps/ieee754/dbl2mpn.c: Update copyright. * sysdeps/ieee754/ldbl2mpn.c: Likewise. * sysdeps/ieee754/mpn2dbl.c: Likewise. * sysdeps/ieee754/mpn2flt.c: Likewise. * sysdeps/ieee754/mpn2ldbl.c: Likewise. * sysdeps/unix/sysv/linux/poll.c: Implement poll function by falling back to select-based implementation if syscall isn't available. * sysdeps/unix/sysv/linux/syscalls.list: Add s_poll. * time/leapseconds: Update from tzdata1997b. * time/zic.c: Update from tzcode1997b. 1997-03-01 15:08 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * time/Makefile $(tzfiles:%=$(objpfx)z.%): Remove unneeded depedencies between installed $(tzlinks) and $(tzbases) files. 1997-03-01 14:27 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * math/math.h: Make compatible with traditional preprocessor; requires carefull placement of whitespace in macro arguments. Use __CONCAT instead of ##. Declare long double functions only if __STDC__ or __GNUC__. * math/mathcall.h: Avoid whitespace before argument of macro call that is used as function name. * sysdeps/m68k/fpu/__math.h: Use __CONCAT instead of ##. (__m81_u, __m81_inline): Depend on __LIBC_M81_MATH_INLINES instead of __NO_M81_MATH_INLINES. [!__LIBC_M81_MATH_INLINES]: Don't define internal functions starting with __ieee754. [!__NO_MATH_INLINES && __OPTIMIZE__]: Define user visible functions as inlines. (__m81_defun): Put __attribute__ between return type and function name. * math/math.h: Include <__math.h> also if __LIBC_M81_MATH_INLINES is defined. * sysdeps/m68k/fpu/e_acos.c: Define __LIBC_M81_MATH_INLINES instead of __NO_M81_MATH_INLINES. * sysdeps/m68k/fpu/e_fmod.c: Likewise. * sysdeps/m68k/fpu/k_cos.c: Likewise. * sysdeps/m68k/fpu/k_sin.c: Likewise. * sysdeps/m68k/fpu/k_tan.c: Likewise. * sysdeps/m68k/fpu/s_atan.c: Likewise. De-ANSI-declify. * sysdeps/m68k/fpu/s_frexp.c: Likewise. * sysdeps/m68k/fpu/s_ilogb.c: Likewise. * sysdeps/m68k/fpu/s_isinf.c: Likewise. * sysdeps/m68k/fpu/s_modf.c: Likewise. * sysdeps/m68k/fpu/s_scalbn.c: Likewise. 1997-02-27 21:51 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * Makefile (tests): Cope with $PATH not including the current directory. 1997-02-27 18:04 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/Makefile ($(common-objpfx)mk-local_lim): Use $(common-objdir-compile). ($(common-objpfx)make-ioctls): Likewise. (mk-local_lim-CFLAGS): Set this instead of local_lim-CFLAGS. ($(common-objpfx)sys/param.h): Use $(make-target-directory). ($(addprefix $(common-objpfx),$(sys/param.h-includes))): Likewise. ($(common-objpfx)sys/syscall.h): Likewise. ($(common-objpfx)local_lim.h): Let make deal with command failure. ($(common-objpfx)param.h.dep): Use temporary file and update target atomically. ($(common-objpfx)errnos): Avoid the Useless Use of cat Award. (include $(common-objpfx)param.h.dep): Ignore error. * sysdeps/posix/Makefile ($(common-objpfx)mk-stdiolim): Use $(common-objdir-compile). (mk-stdiolim-CFLAGS): Renamed from cded-objdir-includes, use $(shell pwd) instead of $$cwd. * sysdeps/generic/Makefile ($(common-objpfx)det_endian): Use $(common-objdir-compile). ($(objpfx)make_siglist): Use $(native-compile). (make_siglist-CFLAGS): New variable. * Makerules (ALL_BUILD_CFLAGS): Renamed from BUILD_CFLAGS, leaving the old name for the user to pass additional flags to the host compiler. Fix reference to config header. (native-compile, common-objdir-compile): Rewritten to make more generally usable. * sysdeps/unix/sysv/sysv4/solaris2/Makefile: Set ALL_BUILD_CFLAGS instead of BUILD_CFLAGS. * sysvips/sys/ipc.h: Warn if needed feature select macro are not defined. 1997-02-27 17:11 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sunrpc/Makefile ($(objpfx)rpc-proto.d, $(objpfx)rpc-proto.c): New rules to generate dependencies for the RPC service objects. 1997-02-27 16:26 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * argp/argp-parse.c (parser_finalize): Always set *END_INDEX if supplied. 1997-02-28 03:27 Ulrich Drepper <drepper@cygnus.com> * stdlib/strtod.c (STRTOF): Make sure return value is large enough so that clearing second word is necessary. * sysdeps/unix/sysv/linux/netinet/in_systm.h: Don't use kernel header since it is wrong for 64 bit systems. Patch by a sun <asun@zoology.washington.edu>. 1997-02-27 10:34:11 Richard Henderson <rth@tamu.edu> * sysdeps/unix/sysv/linux/alpha/brk.S: Support both the Linux/i386 and OSF/1 style brk syscalls. We may want to change Linux/Alpha for the benefit of running foreign binaries. 1997-03-01 20:21 Miles Bader <miles@gnu.ai.mit.edu> 1997-02-25 19:42 Miles Bader <miles@gnu.ai.mit.edu>
This commit is contained in:
163
stdlib/strtod.c
163
stdlib/strtod.c
@ -40,6 +40,8 @@
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# define CHAR_TYPE wint_t
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# define L_(Ch) L##Ch
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# define ISSPACE(Ch) iswspace (Ch)
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# define ISDIGIT(Ch) iswdigit (Ch)
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# define ISXDIGIT(Ch) iswxdigit (Ch)
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# define TOLOWER(Ch) towlower (Ch)
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# define STRNCASECMP(S1, S2, N) __wcsncasecmp ((S1), (S2), (N))
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#else
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@ -47,6 +49,8 @@
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# define CHAR_TYPE char
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# define L_(Ch) Ch
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# define ISSPACE(Ch) isspace (Ch)
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# define ISDIGIT(Ch) isdigit (Ch)
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# define ISXDIGIT(Ch) isxdigit (Ch)
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# define TOLOWER(Ch) tolower (Ch)
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# define STRNCASECMP(S1, S2, N) __strncasecmp ((S1), (S2), (N))
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#endif
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@ -125,6 +129,7 @@ static const mp_limb_t _tens_in_limb[MAX_DIG_PER_LIMB + 1] =
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#define SWAP(x, y) ({ typeof(x) _tmp = x; x = y; y = _tmp; })
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#define NDIG (MAX_10_EXP - MIN_10_EXP + 2 * MANT_DIG)
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#define HEXNDIG ((MAX_EXP - MIN_EXP + 7) / 8 + 2 * MANT_DIG)
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#define RETURN_LIMB_SIZE howmany (MANT_DIG, BITS_PER_MP_LIMB)
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#define RETURN(val,end) \
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@ -239,7 +244,7 @@ str_to_mpn (const STRING_TYPE *str, int digcnt, mp_limb_t *n, mp_size_t *nsize,
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/* Number of digits for actual limb. */
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int cnt = 0;
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mp_limb_t low = 0;
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mp_limb_t base;
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mp_limb_t start;
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*nsize = 0;
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assert (digcnt > 0);
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@ -262,9 +267,10 @@ str_to_mpn (const STRING_TYPE *str, int digcnt, mp_limb_t *n, mp_size_t *nsize,
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low = 0;
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}
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/* There might be thousands separators or radix characters in the string.
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But these all can be ignored because we know the format of the number
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is correct and we have an exact number of characters to read. */
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/* There might be thousands separators or radix characters in
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the string. But these all can be ignored because we know the
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format of the number is correct and we have an exact number
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of characters to read. */
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while (*str < L_('0') || *str > L_('9'))
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++str;
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low = low * 10 + *str++ - L_('0');
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@ -275,11 +281,11 @@ str_to_mpn (const STRING_TYPE *str, int digcnt, mp_limb_t *n, mp_size_t *nsize,
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if (*exponent > 0 && cnt + *exponent <= MAX_DIG_PER_LIMB)
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{
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low *= _tens_in_limb[*exponent];
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base = _tens_in_limb[cnt + *exponent];
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start = _tens_in_limb[cnt + *exponent];
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*exponent = 0;
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}
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else
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base = _tens_in_limb[cnt];
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start = _tens_in_limb[cnt];
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if (*nsize == 0)
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{
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@ -289,11 +295,12 @@ str_to_mpn (const STRING_TYPE *str, int digcnt, mp_limb_t *n, mp_size_t *nsize,
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else
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{
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mp_limb_t cy;
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cy = __mpn_mul_1 (n, n, *nsize, base);
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cy = __mpn_mul_1 (n, n, *nsize, start);
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cy += __mpn_add_1 (n, n, *nsize, low);
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if (cy != 0)
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n[(*nsize)++] = cy;
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}
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return str;
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}
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@ -346,6 +353,9 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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MPN_VAR (num); /* MP representation of the number. */
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int exponent; /* Exponent of the number. */
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/* Numbers starting `0X' or `0x' have to be processed with base 16. */
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int base = 10;
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/* When we have to compute fractional digits we form a fraction with a
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second multi-precision number (and we sometimes need a second for
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temporary results). */
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@ -485,6 +495,18 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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RETURN (0.0, nptr);
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}
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/* First look whether we are faced with a hexadecimal number. */
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if (c == L_('0') && TOLOWER (cp[1]) == L_('x'))
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{
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/* Okay, it is a hexa-decimal number. Remember this and skip
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the characters. BTW: hexadecimal numbers must not be
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grouped. */
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base = 16;
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cp += 2;
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c = *cp;
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grouping = NULL;
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}
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/* Record the start of the digits, in case we will check their grouping. */
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start_of_digits = startp = cp;
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@ -494,25 +516,29 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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/* If no other digit but a '0' is found the result is 0.0.
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Return current read pointer. */
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if ((c < L_('0') || c > L_('9')) && (wint_t) c != decimal
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&& TOLOWER (c) != L_('e'))
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if ((c < L_('0') || c > L_('9')) &&
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(base == 16 && (c < TOLOWER (L_('a')) || c > TOLOWER (L_('f')))) &&
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(wint_t) c != decimal &&
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(base == 16 && (cp == start_of_digits || TOLOWER (c) != L_('p'))) &&
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(base != 16 && TOLOWER (c) != L_('e')))
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{
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tp = correctly_grouped_prefix (start_of_digits, cp, thousands, grouping);
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/* If TP is at the start of the digits, there was no correctly
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grouped prefix of the string; so no number found. */
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RETURN (0.0, tp == start_of_digits ? nptr : tp);
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RETURN (0.0, tp == start_of_digits ? (base == 16 ? cp - 1 : nptr) : tp);
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}
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/* Remember first significant digit and read following characters until the
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decimal point, exponent character or any non-FP number character. */
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startp = cp;
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dig_no = 0;
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while (dig_no < NDIG ||
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while (dig_no < (base == 16 ? HEXNDIG : NDIG) ||
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/* If parsing grouping info, keep going past useful digits
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so we can check all the grouping separators. */
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grouping)
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{
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if (c >= L_('0') && c <= L_('9'))
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if ((c >= L_('0') && c <= L_('9'))
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|| (base == 16 && TOLOWER (c) >= L_('a') && TOLOWER (c) <= L_('f')))
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++dig_no;
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else if (thousands == L'\0' || (wint_t) c != thousands)
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/* Not a digit or separator: end of the integer part. */
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@ -552,7 +578,7 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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}
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}
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if (dig_no >= NDIG)
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if (dig_no >= (base == 16 ? HEXNDIG : NDIG))
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/* Too many digits to be representable. Assigning this to EXPONENT
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allows us to read the full number but return HUGE_VAL after parsing. */
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exponent = MAX_10_EXP;
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@ -567,7 +593,8 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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if ((wint_t) c == decimal)
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{
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c = *++cp;
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while (c >= L_('0') && c <= L_('9'))
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while (c >= L_('0') && c <= L_('9') ||
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(base == 16 && TOLOWER (c) >= L_('a') && TOLOWER (c) <= L_('f')))
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{
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if (c != L_('0') && lead_zero == -1)
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lead_zero = dig_no - int_no;
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@ -580,7 +607,7 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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expp = cp;
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/* Read exponent. */
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if (TOLOWER (c) == L_('e'))
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if (TOLOWER (c) == (base == 16 ? L_('p') : L_('e')))
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{
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int exp_negative = 0;
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@ -598,9 +625,14 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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int exp_limit;
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/* Get the exponent limit. */
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exp_limit = exp_negative ?
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-MIN_10_EXP + MANT_DIG - int_no :
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MAX_10_EXP - int_no + lead_zero;
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if (base == 16)
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exp_limit = (exp_negative ?
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-MIN_EXP + MANT_DIG - 4 * int_no :
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MAX_EXP - 4 * int_no + lead_zero);
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else
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exp_limit = (exp_negative ?
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-MIN_10_EXP + MANT_DIG - int_no :
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MAX_10_EXP - int_no + lead_zero);
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do
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{
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@ -610,11 +642,11 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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/* The exponent is too large/small to represent a valid
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number. */
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{
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FLOAT retval;
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FLOAT result;
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/* Overflow or underflow. */
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__set_errno (ERANGE);
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retval = (exp_negative ? 0.0 :
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result = (exp_negative ? 0.0 :
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negative ? -FLOAT_HUGE_VAL : FLOAT_HUGE_VAL);
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/* Accept all following digits as part of the exponent. */
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@ -622,7 +654,7 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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++cp;
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while (*cp >= L_('0') && *cp <= L_('9'));
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RETURN (retval, cp);
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RETURN (result, cp);
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/* NOTREACHED */
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}
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@ -664,17 +696,89 @@ INTERNAL (STRTOF) (nptr, endptr, group)
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while ((wint_t) *startp != decimal)
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++startp;
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startp += lead_zero + 1;
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exponent -= lead_zero;
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exponent -= base == 16 ? 4 * lead_zero : lead_zero;
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dig_no -= lead_zero;
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}
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/* If the BASE is 16 we can use a simpler algorithm. */
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if (base == 16)
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{
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static const int nbits[16] = { 0, 1, 2, 2, 3, 3, 3, 3,
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4, 4, 4, 4, 4, 4, 4, 4 };
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int idx = (MANT_DIG - 1) / BITS_PER_MP_LIMB;
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int pos = (MANT_DIG - 1) % BITS_PER_MP_LIMB;
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mp_limb_t val;
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while (!ISXDIGIT (*startp))
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++startp;
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if (ISDIGIT (*startp))
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val = *startp++ - L_('0');
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else
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val = 10 + TOLOWER (*startp++) - L_('a');
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bits = nbits[val];
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if (pos + 1 >= 4)
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{
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/* We don't have to care for wrapping. This is the normal
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case so we add this optimization. */
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retval[idx] = val << (pos - bits + 1);
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pos -= bits;
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}
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else
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{
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if (pos + 1 >= bits)
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{
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retval[idx] = val << (pos - bits + 1);
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pos -= bits;
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}
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else
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{
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retval[idx--] = val >> (bits - pos - 1);
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retval[idx] = val << (BITS_PER_MP_LIMB - (bits - pos - 1));
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pos = BITS_PER_MP_LIMB - 1 - (bits - pos - 1);
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}
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}
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while (--dig_no > 0 && idx >= 0)
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{
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while (!ISXDIGIT (*startp))
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++startp;
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if (ISDIGIT (*startp))
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val = *startp++ - L_('0');
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else
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val = 10 + TOLOWER (*startp++) - L_('a');
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if (pos + 1 >= 4)
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{
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retval[idx] |= val << (pos - 4 + 1);
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pos -= 4;
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}
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else
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{
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retval[idx--] |= val >> (4 - pos - 1);
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val <<= BITS_PER_MP_LIMB - (4 - pos - 1);
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if (idx < 0)
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return round_and_return (retval, exponent, negative, val,
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BITS_PER_MP_LIMB - 1, dig_no > 0);
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retval[idx] = val;
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pos = BITS_PER_MP_LIMB - 1 - (4 - pos - 1);
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}
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}
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/* We ran out of digits. */
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MPN_ZERO (retval, idx);
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return round_and_return (retval, exponent, negative, 0, 0, 0);
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}
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/* Now we have the number of digits in total and the integer digits as well
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as the exponent and its sign. We can decide whether the read digits are
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really integer digits or belong to the fractional part; i.e. we normalize
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123e-2 to 1.23. */
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{
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register int incr = exponent < 0 ? MAX (-int_no, exponent)
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: MIN (dig_no - int_no, exponent);
|
||||
register int incr = (exponent < 0 ? MAX (-int_no, exponent)
|
||||
: MIN (dig_no - int_no, exponent));
|
||||
int_no += incr;
|
||||
exponent -= incr;
|
||||
}
|
||||
@ -711,9 +815,10 @@ INTERNAL (STRTOF) (nptr, endptr, group)
|
||||
mp_limb_t cy;
|
||||
exponent ^= expbit;
|
||||
|
||||
/* FIXME: not the whole multiplication has to be done.
|
||||
If we have the needed number of bits we only need the
|
||||
information whether more non-zero bits follow. */
|
||||
/* FIXME: not the whole multiplication has to be
|
||||
done. If we have the needed number of bits we
|
||||
only need the information whether more non-zero
|
||||
bits follow. */
|
||||
if (numsize >= ttab->arraysize - _FPIO_CONST_OFFSET)
|
||||
cy = __mpn_mul (pdest, psrc, numsize,
|
||||
&ttab->array[_FPIO_CONST_OFFSET],
|
||||
@ -848,7 +953,7 @@ INTERNAL (STRTOF) (nptr, endptr, group)
|
||||
assert (dig_no > int_no && exponent <= 0);
|
||||
|
||||
|
||||
/* For the fractional part we need not process too much digits. One
|
||||
/* For the fractional part we need not process too many digits. One
|
||||
decimal digits gives us log_2(10) ~ 3.32 bits. If we now compute
|
||||
ceil(BITS / 3) =: N
|
||||
digits we should have enough bits for the result. The remaining
|
||||
@ -1126,7 +1231,9 @@ INTERNAL (STRTOF) (nptr, endptr, group)
|
||||
for (i = RETURN_LIMB_SIZE; i > empty; --i)
|
||||
retval[i] = retval[i - empty];
|
||||
#endif
|
||||
#if RETURN_LIMB_SIZE > 1
|
||||
retval[1] = 0;
|
||||
#endif
|
||||
for (i = numsize; i > 0; --i)
|
||||
num[i + empty] = num[i - 1];
|
||||
MPN_ZERO (num, empty + 1);
|
||||
|
Reference in New Issue
Block a user