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[PATCH 3/6] float128: Add strfromf128
- From: "Gabriel F. T. Gomes" <gftg at linux dot vnet dot ibm dot com>
- To: libc-alpha at sourceware dot org
- Date: Fri, 26 May 2017 09:56:33 -0300
- Subject: [PATCH 3/6] float128: Add strfromf128
- Authentication-results: sourceware.org; auth=none
- References: <1495803396-14558-1-git-send-email-gftg@linux.vnet.ibm.com>
Add strfromf128 to stdlib when _Float128 support is enabled.
2016-11-07 Gabriel F. T. Gomes <gftg@linux.vnet.ibm.com>
* NEWS: Mention the addition of strfromf128.
* include/gmp.h: Include bits/floatn.h for _Float128 support.
* stdio-common/printf-parsemb.c (__parse_one_specmb): Initialize
spec->info.is_binary128 to zero.
* stdio-common/printf.h (printf_info): Add new member is_binary128
to indicate that the number being converted to string is compatible
with the IEC 60559 binary128 format.
* stdio-common/printf_fp.c (__printf_fp_l): Add code to deal with
_Float128 numbers.
* stdio-common/printf_fphex.c (__printf_fphex): Likewise.
* stdio-common/printf_size.c (__printf_size): Likewise.
* stdio-common/vfprintf.c (process_arg): Initialize member
info.is_binary128 to zero.
* stdlib/fpioconst.h (FLT128_MAX_10_EXP_LOG): New macro.
* stdlib/stdlib.h: Include bits/floatn.h for _Float128 support.
(strfromf128): New declaration.
* stdlib/strfrom-skeleton.c (STRFROM): Set member info.is_binary128
to one.
* sysdeps/ieee754/float128/Makefile: Add strfromf128.
* sysdeps/ieee754/float128/Versions: Likewise.
* sysdeps/ieee754/float128/strfromf128.c: New file.
---
NEWS | 3 +
include/gmp.h | 2 +
stdio-common/printf-parsemb.c | 1 +
stdio-common/printf.h | 4 +-
stdio-common/printf_fp.c | 103 ++++++++++++++++++++++++-
stdio-common/printf_fphex.c | 134 +++++++++++++++++++++++++++++++++
stdio-common/printf_size.c | 29 +++++++
stdio-common/vfprintf.c | 10 ++-
stdlib/fpioconst.h | 4 +
stdlib/stdlib.h | 8 ++
stdlib/strfrom-skeleton.c | 6 ++
sysdeps/ieee754/float128/Makefile | 2 +-
sysdeps/ieee754/float128/Versions | 5 ++
sysdeps/ieee754/float128/strfromf128.c | 25 ++++++
14 files changed, 328 insertions(+), 8 deletions(-)
create mode 100644 sysdeps/ieee754/float128/strfromf128.c
diff --git a/NEWS b/NEWS
index b4ecd62..8cb17cc 100644
--- a/NEWS
+++ b/NEWS
@@ -66,6 +66,9 @@ Version 2.26
* The port to Native Client running on ARMv7-A (--host=arm-nacl) has been
removed.
+* The function strfromf128, from ISO/IEC TS 18661-3:2015, is added to libc.
+ It converts a _Float128 value into string.
+
Security related changes:
* The DNS stub resolver limits the advertised UDP buffer size to 1200 bytes,
diff --git a/include/gmp.h b/include/gmp.h
index 95d6c16..e6f635e 100644
--- a/include/gmp.h
+++ b/include/gmp.h
@@ -6,6 +6,8 @@
#include <stdlib/gmp.h>
+#include <bits/floatn.h>
+
/* Now define the internal interfaces. */
extern mp_size_t __mpn_extract_double (mp_ptr res_ptr, mp_size_t size,
int *expt, int *is_neg,
diff --git a/stdio-common/printf-parsemb.c b/stdio-common/printf-parsemb.c
index edb066e..a42336c 100644
--- a/stdio-common/printf-parsemb.c
+++ b/stdio-common/printf-parsemb.c
@@ -79,6 +79,7 @@ __parse_one_specmb (const UCHAR_T *format, size_t posn,
spec->info.extra = 0;
spec->info.pad = ' ';
spec->info.wide = sizeof (UCHAR_T) > 1;
+ spec->info.is_binary128 = 0;
/* Test for positional argument. */
if (ISDIGIT (*format))
diff --git a/stdio-common/printf.h b/stdio-common/printf.h
index 5d82e8d..6b207d2 100644
--- a/stdio-common/printf.h
+++ b/stdio-common/printf.h
@@ -47,7 +47,9 @@ struct printf_info
unsigned int is_char:1; /* hh flag. */
unsigned int wide:1; /* Nonzero for wide character streams. */
unsigned int i18n:1; /* I flag. */
- unsigned int __pad:4; /* Unused so far. */
+ unsigned int is_binary128:1; /* Floating-point argument is ABI-compatible
+ with IEC 60559 binary128. */
+ unsigned int __pad:3; /* Unused so far. */
unsigned short int user; /* Bits for user-installed modifiers. */
wchar_t pad; /* Padding character. */
};
diff --git a/stdio-common/printf_fp.c b/stdio-common/printf_fp.c
index 7845d96..f6335c5 100644
--- a/stdio-common/printf_fp.c
+++ b/stdio-common/printf_fp.c
@@ -218,6 +218,9 @@ __printf_fp_l (FILE *fp, locale_t loc,
{
double dbl;
__long_double_t ldbl;
+#if __HAVE_DISTINCT_FLOAT128
+ _Float128 f128;
+#endif
}
fpnum;
@@ -234,9 +237,17 @@ __printf_fp_l (FILE *fp, locale_t loc,
const char *special = NULL;
const wchar_t *wspecial = NULL;
+ /* When _Float128 is enabled in the library and ABI-distinct from long
+ double, we need mp_limbs enough for any of them. */
+#if __HAVE_DISTINCT_FLOAT128
+# define GREATER_MANT_DIG FLT128_MANT_DIG
+#else
+# define GREATER_MANT_DIG LDBL_MANT_DIG
+#endif
/* We need just a few limbs for the input before shifting to the right
position. */
- mp_limb_t fp_input[(LDBL_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB];
+ mp_limb_t fp_input[(GREATER_MANT_DIG + BITS_PER_MP_LIMB - 1)
+ / BITS_PER_MP_LIMB];
/* We need to shift the contents of fp_input by this amount of bits. */
int to_shift = 0;
@@ -328,6 +339,52 @@ __printf_fp_l (FILE *fp, locale_t loc,
grouping = NULL;
/* Fetch the argument value. */
+#if __HAVE_DISTINCT_FLOAT128
+ if (info->is_binary128)
+ {
+ fpnum.f128 = *(const _Float128 *) args[0];
+
+ /* Check for special values: not a number or infinity. */
+ if (isnan (fpnum.f128))
+ {
+ is_neg = signbit (fpnum.f128);
+ if (isupper (info->spec))
+ {
+ special = "NAN";
+ wspecial = L"NAN";
+ }
+ else
+ {
+ special = "nan";
+ wspecial = L"nan";
+ }
+ }
+ else if (isinf (fpnum.f128))
+ {
+ is_neg = signbit (fpnum.f128);
+ if (isupper (info->spec))
+ {
+ special = "INF";
+ wspecial = L"INF";
+ }
+ else
+ {
+ special = "inf";
+ wspecial = L"inf";
+ }
+ }
+ else
+ {
+ p.fracsize = __mpn_extract_float128 (fp_input,
+ (sizeof (fp_input) /
+ sizeof (fp_input[0])),
+ &p.exponent, &is_neg,
+ fpnum.f128);
+ to_shift = 1 + p.fracsize * BITS_PER_MP_LIMB - FLT128_MANT_DIG;
+ }
+ }
+ else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
#ifndef __NO_LONG_DOUBLE_MATH
if (info->is_long_double && sizeof (long double) > sizeof (double))
{
@@ -450,7 +507,8 @@ __printf_fp_l (FILE *fp, locale_t loc,
{
mp_size_t bignum_size = ((abs (p.exponent) + BITS_PER_MP_LIMB - 1)
/ BITS_PER_MP_LIMB
- + (LDBL_MANT_DIG / BITS_PER_MP_LIMB > 2 ? 8 : 4))
+ + (GREATER_MANT_DIG / BITS_PER_MP_LIMB > 2
+ ? 8 : 4))
* sizeof (mp_limb_t);
p.frac = (mp_limb_t *) alloca (bignum_size);
p.tmp = (mp_limb_t *) alloca (bignum_size);
@@ -465,7 +523,15 @@ __printf_fp_l (FILE *fp, locale_t loc,
{
/* |FP| >= 8.0. */
int scaleexpo = 0;
- int explog = LDBL_MAX_10_EXP_LOG;
+ int explog;
+#if __HAVE_DISTINCT_FLOAT128
+ if (info->is_binary128)
+ explog = FLT128_MAX_10_EXP_LOG;
+ else
+ explog = LDBL_MAX_10_EXP_LOG;
+#else
+ explog = LDBL_MAX_10_EXP_LOG;
+#endif
int exp10 = 0;
const struct mp_power *powers = &_fpioconst_pow10[explog + 1];
int cnt_h, cnt_l, i;
@@ -499,6 +565,27 @@ __printf_fp_l (FILE *fp, locale_t loc,
{
if (p.scalesize == 0)
{
+#if __HAVE_DISTINCT_FLOAT128
+ if ((FLT128_MANT_DIG
+ > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB)
+ && info->is_binary128)
+ {
+#define _FLT128_FPIO_CONST_SHIFT \
+ (((FLT128_MANT_DIG + BITS_PER_MP_LIMB - 1) / BITS_PER_MP_LIMB) \
+ - _FPIO_CONST_OFFSET)
+ /* 64bit const offset is not enough for
+ IEEE 854 quad long double (_Float128). */
+ p.tmpsize = powers->arraysize + _FLT128_FPIO_CONST_SHIFT;
+ memcpy (p.tmp + _FLT128_FPIO_CONST_SHIFT,
+ &__tens[powers->arrayoff],
+ p.tmpsize * sizeof (mp_limb_t));
+ MPN_ZERO (p.tmp, _FLT128_FPIO_CONST_SHIFT);
+ /* Adjust p.exponent, as scaleexpo will be this much
+ bigger too. */
+ p.exponent += _FLT128_FPIO_CONST_SHIFT * BITS_PER_MP_LIMB;
+ }
+ else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
#ifndef __NO_LONG_DOUBLE_MATH
if (LDBL_MANT_DIG > _FPIO_CONST_OFFSET * BITS_PER_MP_LIMB
&& info->is_long_double)
@@ -639,7 +726,15 @@ __printf_fp_l (FILE *fp, locale_t loc,
{
/* |FP| < 1.0. */
int exp10 = 0;
- int explog = LDBL_MAX_10_EXP_LOG;
+ int explog;
+#if __HAVE_DISTINCT_FLOAT128
+ if (info->is_binary128)
+ explog = FLT128_MAX_10_EXP_LOG;
+ else
+ explog = LDBL_MAX_10_EXP_LOG;
+#else
+ explog = LDBL_MAX_10_EXP_LOG;
+#endif
const struct mp_power *powers = &_fpioconst_pow10[explog + 1];
/* Now shift the input value to its right place. */
diff --git a/stdio-common/printf_fphex.c b/stdio-common/printf_fphex.c
index b207e00..d5573b1 100644
--- a/stdio-common/printf_fphex.c
+++ b/stdio-common/printf_fphex.c
@@ -31,6 +31,10 @@
#include <stdbool.h>
#include <rounding-mode.h>
+#if __HAVE_DISTINCT_FLOAT128
+# include "ieee754_float128.h"
+#endif
+
/* #define NDEBUG 1*/ /* Undefine this for debugging assertions. */
#include <assert.h>
@@ -94,6 +98,9 @@ __printf_fphex (FILE *fp,
{
union ieee754_double dbl;
long double ldbl;
+#if __HAVE_DISTINCT_FLOAT128
+ _Float128 flt128;
+#endif
}
fpnum;
@@ -159,6 +166,45 @@ __printf_fphex (FILE *fp,
/* Fetch the argument value. */
+#if __HAVE_DISTINCT_FLOAT128
+ if (info->is_binary128)
+ {
+ fpnum.flt128 = *(const _Float128 *) args[0];
+
+ /* Check for special values: not a number or infinity. */
+ if (isnan (fpnum.flt128))
+ {
+ if (isupper (info->spec))
+ {
+ special = "NAN";
+ wspecial = L"NAN";
+ }
+ else
+ {
+ special = "nan";
+ wspecial = L"nan";
+ }
+ }
+ else
+ {
+ if (isinf (fpnum.flt128))
+ {
+ if (isupper (info->spec))
+ {
+ special = "INF";
+ wspecial = L"INF";
+ }
+ else
+ {
+ special = "inf";
+ wspecial = L"inf";
+ }
+ }
+ }
+ negative = signbit (fpnum.flt128);
+ }
+ else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
#ifndef __NO_LONG_DOUBLE_MATH
if (info->is_long_double && sizeof (long double) > sizeof (double))
{
@@ -260,6 +306,94 @@ __printf_fphex (FILE *fp,
return done;
}
+#if __HAVE_DISTINCT_FLOAT128
+ /* This block is copied from sysdeps/ieee754/ldbl-128/printf_fphex.c. */
+ if (info->is_binary128)
+ {
+ /* We have 112 bits of mantissa plus one implicit digit. Since
+ 112 bits are representable without rest using hexadecimal
+ digits we use only the implicit digits for the number before
+ the decimal point. */
+ unsigned long long int num0, num1;
+ union ieee854_float128 u;
+ u.d = fpnum.flt128;
+
+ num0 = (((unsigned long long int) u.ieee.mantissa0) << 32
+ | u.ieee.mantissa1);
+ num1 = (((unsigned long long int) u.ieee.mantissa2) << 32
+ | u.ieee.mantissa3);
+
+ zero_mantissa = (num0|num1) == 0;
+
+ if (sizeof (unsigned long int) > 6)
+ {
+ numstr = _itoa_word (num1, numbuf + sizeof numbuf, 16,
+ info->spec == 'A');
+ wnumstr = _itowa_word (num1,
+ wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t),
+ 16, info->spec == 'A');
+ }
+ else
+ {
+ numstr = _itoa (num1, numbuf + sizeof numbuf, 16,
+ info->spec == 'A');
+ wnumstr = _itowa (num1,
+ wnumbuf + sizeof (wnumbuf) / sizeof (wchar_t),
+ 16, info->spec == 'A');
+ }
+
+ while (numstr > numbuf + (sizeof numbuf - 64 / 4))
+ {
+ *--numstr = '0';
+ *--wnumstr = L'0';
+ }
+
+ if (sizeof (unsigned long int) > 6)
+ {
+ numstr = _itoa_word (num0, numstr, 16, info->spec == 'A');
+ wnumstr = _itowa_word (num0, wnumstr, 16, info->spec == 'A');
+ }
+ else
+ {
+ numstr = _itoa (num0, numstr, 16, info->spec == 'A');
+ wnumstr = _itowa (num0, wnumstr, 16, info->spec == 'A');
+ }
+
+ /* Fill with zeroes. */
+ while (numstr > numbuf + (sizeof numbuf - 112 / 4))
+ {
+ *--numstr = '0';
+ *--wnumstr = L'0';
+ }
+
+ leading = u.ieee.exponent == 0 ? '0' : '1';
+
+ exponent = u.ieee.exponent;
+
+ if (exponent == 0)
+ {
+ if (zero_mantissa)
+ expnegative = 0;
+ else
+ {
+ /* This is a denormalized number. */
+ expnegative = 1;
+ exponent = IEEE854_FLOAT128_BIAS - 1;
+ }
+ }
+ else if (exponent >= IEEE854_FLOAT128_BIAS)
+ {
+ expnegative = 0;
+ exponent -= IEEE854_FLOAT128_BIAS;
+ }
+ else
+ {
+ expnegative = 1;
+ exponent = -(exponent - IEEE854_FLOAT128_BIAS);
+ }
+ }
+ else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
if (info->is_long_double == 0 || sizeof (double) == sizeof (long double))
{
/* We have 52 bits of mantissa plus one implicit digit. Since
diff --git a/stdio-common/printf_size.c b/stdio-common/printf_size.c
index 9403aea..3449d17 100644
--- a/stdio-common/printf_size.c
+++ b/stdio-common/printf_size.c
@@ -104,6 +104,9 @@ __printf_size (FILE *fp, const struct printf_info *info,
{
union ieee754_double dbl;
long double ldbl;
+#if __HAVE_DISTINCT_FLOAT128
+ _Float128 f128;
+#endif
}
fpnum;
const void *ptr = &fpnum;
@@ -119,6 +122,32 @@ __printf_size (FILE *fp, const struct printf_info *info,
int wide = info->wide;
/* Fetch the argument value. */
+#if __HAVE_DISTINCT_FLOAT128
+ if (info->is_binary128)
+ {
+ fpnum.f128 = *(const _Float128 *) args[0];
+
+ /* Check for special values: not a number or infinity. */
+ if (isnan (fpnum.f128))
+ {
+ special = "nan";
+ wspecial = L"nan";
+ }
+ else if (isinf (fpnum.f128))
+ {
+ is_neg = signbit (fpnum.f128);
+ special = "inf";
+ wspecial = L"inf";
+ }
+ else
+ while (fpnum.f128 >= divisor && tag[1] != '\0')
+ {
+ fpnum.f128 /= divisor;
+ ++tag;
+ }
+ }
+ else
+#endif /* __HAVE_DISTINCT_FLOAT128 */
#ifndef __NO_LONG_DOUBLE_MATH
if (info->is_long_double && sizeof (long double) > sizeof (double))
{
diff --git a/stdio-common/vfprintf.c b/stdio-common/vfprintf.c
index 2cf7c8a..b8c87a5 100644
--- a/stdio-common/vfprintf.c
+++ b/stdio-common/vfprintf.c
@@ -770,7 +770,8 @@ static const uint8_t jump_table[] =
.pad = pad, \
.extra = 0, \
.i18n = use_outdigits, \
- .wide = sizeof (CHAR_T) != 1 }; \
+ .wide = sizeof (CHAR_T) != 1, \
+ .is_binary128 = 0}; \
\
if (is_long_double) \
the_arg.pa_long_double = va_arg (ap, long double); \
@@ -788,6 +789,8 @@ static const uint8_t jump_table[] =
fspec->data_arg_type = PA_DOUBLE; \
fspec->info.is_long_double = 0; \
} \
+ /* Not supported by *printf functions. */ \
+ fspec->info.is_binary128 = 0; \
\
function_done = __printf_fp (s, &fspec->info, &ptr); \
} \
@@ -827,7 +830,8 @@ static const uint8_t jump_table[] =
.group = group, \
.pad = pad, \
.extra = 0, \
- .wide = sizeof (CHAR_T) != 1 }; \
+ .wide = sizeof (CHAR_T) != 1, \
+ .is_binary128 = 0}; \
\
if (is_long_double) \
the_arg.pa_long_double = va_arg (ap, long double); \
@@ -842,6 +846,8 @@ static const uint8_t jump_table[] =
ptr = (const void *) &args_value[fspec->data_arg]; \
if (__ldbl_is_dbl) \
fspec->info.is_long_double = 0; \
+ /* Not supported by *printf functions. */ \
+ fspec->info.is_binary128 = 0; \
\
function_done = __printf_fphex (s, &fspec->info, &ptr); \
} \
diff --git a/stdlib/fpioconst.h b/stdlib/fpioconst.h
index 7e19b0d..aab46d6 100644
--- a/stdlib/fpioconst.h
+++ b/stdlib/fpioconst.h
@@ -44,6 +44,10 @@
IBM extended precision). */
#include <bits/floatn.h>
+#if __HAVE_DISTINCT_FLOAT128
+# define FLT128_MAX_10_EXP_LOG 12 /* = floor(log_2(FLT128_MAX_10_EXP)) */
+#endif
+
/* For strtold, we need powers of 10 up to floor (log_2 (LDBL_MANT_DIG
- LDBL_MIN_EXP + 2)). When _Float128 is enabled in libm and it is
ABI-distinct from long double (e.g. on powerpc64le), we also need powers
diff --git a/stdlib/stdlib.h b/stdlib/stdlib.h
index 99125f2..1313aa5 100644
--- a/stdlib/stdlib.h
+++ b/stdlib/stdlib.h
@@ -51,6 +51,9 @@ __BEGIN_DECLS
# endif
#endif /* X/Open or XPG7 and <sys/wait.h> not included. */
+/* _FloatN API tests for enablement. */
+#include <bits/floatn.h>
+
/* Returned by `div'. */
typedef struct
{
@@ -173,6 +176,11 @@ extern int strfromf (char *__dest, size_t __size, const char *__format,
extern int strfroml (char *__dest, size_t __size, const char *__format,
long double __f)
__THROW __nonnull ((3));
+# if __HAVE_FLOAT128 && __GLIBC_USE (IEC_60559_TYPES_EXT)
+extern int strfromf128 (char *__dest, size_t __size, const char * __format,
+ _Float128 __f)
+ __THROW __nonnull ((3));
+# endif
#endif
diff --git a/stdlib/strfrom-skeleton.c b/stdlib/strfrom-skeleton.c
index 811a29c..5841919 100644
--- a/stdlib/strfrom-skeleton.c
+++ b/stdlib/strfrom-skeleton.c
@@ -132,6 +132,12 @@ STRFROM (char *dest, size_t size, const char *format, FLOAT f)
which type of floating-point number is being passed. */
info.is_long_double = __builtin_types_compatible_p (FLOAT, long double);
+ /* Similarly, the function strfromf128 passes a floating-point number in
+ _Float128 format to printf_fp. */
+#if __HAVE_DISTINCT_FLOAT128
+ info.is_binary128 = __builtin_types_compatible_p (FLOAT, _Float128);
+#endif
+
/* Set info according to the format string. */
info.prec = precision;
info.spec = specifier;
diff --git a/sysdeps/ieee754/float128/Makefile b/sysdeps/ieee754/float128/Makefile
index 6a7b0e0..c07586c 100644
--- a/sysdeps/ieee754/float128/Makefile
+++ b/sysdeps/ieee754/float128/Makefile
@@ -1,3 +1,3 @@
ifeq ($(subdir),stdlib)
-routines += float1282mpn
+routines += float1282mpn strfromf128
endif
diff --git a/sysdeps/ieee754/float128/Versions b/sysdeps/ieee754/float128/Versions
index 9f431d9..caf2064 100644
--- a/sysdeps/ieee754/float128/Versions
+++ b/sysdeps/ieee754/float128/Versions
@@ -2,6 +2,11 @@
%ifndef FLOAT128_VERSION
% error "float128-abi.h must define FLOAT128_VERSION"
%endif
+libc {
+ FLOAT128_VERSION {
+ strfromf128;
+ }
+}
libm {
FLOAT128_VERSION {
__acosf128_finite;
diff --git a/sysdeps/ieee754/float128/strfromf128.c b/sysdeps/ieee754/float128/strfromf128.c
new file mode 100644
index 0000000..597c7e6
--- /dev/null
+++ b/sysdeps/ieee754/float128/strfromf128.c
@@ -0,0 +1,25 @@
+/* Definitions for strfromf128. Implementation in stdlib/strfrom-skeleton.c.
+
+ Copyright (C) 2017 Free Software Foundation, Inc.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#define FLOAT _Float128
+#define STRFROM strfromf128
+
+#include <bits/floatn.h>
+#include <float128_private.h>
+
+#include <stdlib/strfrom-skeleton.c>
--
2.4.11