Long long integer to wide char conversion function.
authordrepper <drepper>
Wed, 16 Jun 1999 22:33:55 +0000 (22:33 +0000)
committerdrepper <drepper>
Wed, 16 Jun 1999 22:33:55 +0000 (22:33 +0000)
stdio-common/_itowa.c [new file with mode: 0644]

diff --git a/stdio-common/_itowa.c b/stdio-common/_itowa.c
new file mode 100644 (file)
index 0000000..430415b
--- /dev/null
@@ -0,0 +1,346 @@
+/* Internal function for converting integers to ASCII.
+   Copyright (C) 1994, 1995, 1996, 1999 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Torbjorn Granlund <tege@matematik.su.se>
+   and Ulrich Drepper <drepper@gnu.org>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <gmp-mparam.h>
+#include <stdlib/gmp.h>
+#include <stdlib/gmp-impl.h>
+#include <stdlib/longlong.h>
+
+#include "_itowa.h"
+
+
+/* Canonize environment.  For some architectures not all values might
+   be defined in the GMP header files.  */
+#ifndef UMUL_TIME
+# define UMUL_TIME 1
+#endif
+#ifndef UDIV_TIME
+# define UDIV_TIME 3
+#endif
+
+/* Control memory layout.  */
+#ifdef PACK
+# undef PACK
+# define PACK __attribute__ ((packed))
+#else
+# define PACK
+#endif
+
+
+/* Declare local types.  */
+struct base_table_t
+{
+#if (UDIV_TIME > 2 * UMUL_TIME)
+  mp_limb_t base_multiplier;
+#endif
+  char flag;
+  char post_shift;
+#if BITS_PER_MP_LIMB == 32
+  struct
+    {
+      char normalization_steps;
+      char ndigits;
+      mp_limb_t base PACK;
+#if UDIV_TIME > 2 * UMUL_TIME
+      mp_limb_t base_ninv PACK;
+#endif
+    } big;
+#endif
+};
+
+/* To reduce the memory needed we include some fields of the tables
+   only conditionally.  */
+#if UDIV_TIME > 2 * UMUL_TIME
+# define SEL1(X) X,
+# define SEL2(X) ,X
+#else
+# define SEL1(X)
+# define SEL2(X)
+#endif
+
+/* Factor table for the different bases.  */
+extern const struct base_table_t _itoa_base_table[];
+
+/* Lower-case digits.  */
+extern const wchar_t _itowa_lower_digits[];
+/* Upper-case digits.  */
+extern const wchar_t _itowa_upper_digits[];
+
+
+wchar_t *
+_itowa (value, buflim, base, upper_case)
+     unsigned long long int value;
+     wchar_t *buflim;
+     unsigned int base;
+     int upper_case;
+{
+  const wchar_t *digits = (upper_case
+                          ? _itowa_upper_digits : _itowa_lower_digits);
+  wchar_t *bp = buflim;
+  const struct base_table_t *brec = &_itoa_base_table[base - 2];
+
+  switch (base)
+    {
+#define RUN_2N(BITS) \
+      do                                                                     \
+        {                                                                    \
+         /* `unsigned long long int' always has 64 bits.  */                 \
+         mp_limb_t work_hi = value >> (64 - BITS_PER_MP_LIMB);               \
+                                                                             \
+         if (BITS_PER_MP_LIMB == 32)                                         \
+           {                                                                 \
+             if (work_hi != 0)                                               \
+               {                                                             \
+                 mp_limb_t work_lo;                                          \
+                 int cnt;                                                    \
+                                                                             \
+                 work_lo = value & 0xfffffffful;                             \
+                 for (cnt = BITS_PER_MP_LIMB / BITS; cnt > 0; --cnt)         \
+                   {                                                         \
+                     *--bp = digits[work_lo & ((1ul << BITS) - 1)];          \
+                     work_lo >>= BITS;                                       \
+                   }                                                         \
+                 if (BITS_PER_MP_LIMB % BITS != 0)                           \
+                   {                                                         \
+                     work_lo                                                 \
+                       |= ((work_hi                                          \
+                            & ((1 << (BITS - BITS_PER_MP_LIMB%BITS))         \
+                               - 1))                                         \
+                           << BITS_PER_MP_LIMB % BITS);                      \
+                     work_hi >>= BITS - BITS_PER_MP_LIMB % BITS;             \
+                     if (work_hi == 0)                                       \
+                       work_hi = work_lo;                                    \
+                     else                                                    \
+                       *--bp = digits[work_lo];                              \
+                   }                                                         \
+               }                                                             \
+             else                                                            \
+               work_hi = value & 0xfffffffful;                               \
+           }                                                                 \
+         do                                                                  \
+           {                                                                 \
+             *--bp = digits[work_hi & ((1 << BITS) - 1)];                    \
+             work_hi >>= BITS;                                               \
+           }                                                                 \
+         while (work_hi != 0);                                               \
+       }                                                                     \
+      while (0)
+    case 8:
+      RUN_2N (3);
+      break;
+
+    case 16:
+      RUN_2N (4);
+      break;
+
+    default:
+      {
+#if BITS_PER_MP_LIMB == 64
+       mp_limb_t base_multiplier = brec->base_multiplier;
+       if (brec->flag)
+         while (value != 0)
+           {
+             mp_limb_t quo, rem, x, dummy;
+
+             umul_ppmm (x, dummy, value, base_multiplier);
+             quo = (x + ((value - x) >> 1)) >> (brec->post_shift - 1);
+             rem = value - quo * base;
+             *--bp = digits[rem];
+             value = quo;
+           }
+       else
+         while (value != 0)
+           {
+             mp_limb_t quo, rem, x, dummy;
+
+             umul_ppmm (x, dummy, value, base_multiplier);
+             quo = x >> brec->post_shift;
+             rem = value - quo * base;
+             *--bp = digits[rem];
+             value = quo;
+           }
+#endif
+#if BITS_PER_MP_LIMB == 32
+       mp_limb_t t[3];
+       int n;
+
+       /* First convert x0 to 1-3 words in base s->big.base.
+          Optimize for frequent cases of 32 bit numbers.  */
+       if ((mp_limb_t) (value >> 32) >= 1)
+         {
+#if UDIV_TIME > 2 * UMUL_TIME || UDIV_NEEDS_NORMALIZATION
+           int big_normalization_steps = brec->big.normalization_steps;
+           mp_limb_t big_base_norm
+             = brec->big.base << big_normalization_steps;
+#endif
+           if ((mp_limb_t) (value >> 32) >= brec->big.base)
+             {
+               mp_limb_t x1hi, x1lo, r;
+               /* If you want to optimize this, take advantage of
+                  that the quotient in the first udiv_qrnnd will
+                  always be very small.  It might be faster just to
+                  subtract in a tight loop.  */
+
+#if UDIV_TIME > 2 * UMUL_TIME
+               mp_limb_t x, xh, xl;
+
+               if (big_normalization_steps == 0)
+                 xh = 0;
+               else
+                 xh = (mp_limb_t) (value >> (64 - big_normalization_steps));
+               xl = (mp_limb_t) (value >> (32 - big_normalization_steps));
+               udiv_qrnnd_preinv (x1hi, r, xh, xl, big_base_norm,
+                                  brec->big.base_ninv);
+
+               xl = ((mp_limb_t) value) << big_normalization_steps;
+               udiv_qrnnd_preinv (x1lo, x, r, xl, big_base_norm,
+                                  brec->big.base_ninv);
+               t[2] = x >> big_normalization_steps;
+
+               if (big_normalization_steps == 0)
+                 xh = x1hi;
+               else
+                 xh = ((x1hi << big_normalization_steps)
+                       | (x1lo >> (32 - big_normalization_steps)));
+               xl = x1lo << big_normalization_steps;
+               udiv_qrnnd_preinv (t[0], x, xh, xl, big_base_norm,
+                                  brec->big.base_ninv);
+               t[1] = x >> big_normalization_steps;
+#elif UDIV_NEEDS_NORMALIZATION
+               mp_limb_t x, xh, xl;
+
+               if (big_normalization_steps == 0)
+                 xh = 0;
+               else
+                 xh = (mp_limb_t) (value >> 64 - big_normalization_steps);
+               xl = (mp_limb_t) (value >> 32 - big_normalization_steps);
+               udiv_qrnnd (x1hi, r, xh, xl, big_base_norm);
+
+               xl = ((mp_limb_t) value) << big_normalization_steps;
+               udiv_qrnnd (x1lo, x, r, xl, big_base_norm);
+               t[2] = x >> big_normalization_steps;
+
+               if (big_normalization_steps == 0)
+                 xh = x1hi;
+               else
+                 xh = ((x1hi << big_normalization_steps)
+                       | (x1lo >> 32 - big_normalization_steps));
+               xl = x1lo << big_normalization_steps;
+               udiv_qrnnd (t[0], x, xh, xl, big_base_norm);
+               t[1] = x >> big_normalization_steps;
+#else
+               udiv_qrnnd (x1hi, r, 0, (mp_limb_t) (value >> 32),
+                           brec->big.base);
+               udiv_qrnnd (x1lo, t[2], r, (mp_limb_t) value, brec->big.base);
+               udiv_qrnnd (t[0], t[1], x1hi, x1lo, brec->big.base);
+#endif
+               n = 3;
+             }
+           else
+             {
+#if (UDIV_TIME > 2 * UMUL_TIME)
+               mp_limb_t x;
+
+               value <<= brec->big.normalization_steps;
+               udiv_qrnnd_preinv (t[0], x, (mp_limb_t) (value >> 32),
+                                  (mp_limb_t) value, big_base_norm,
+                                  brec->big.base_ninv);
+               t[1] = x >> brec->big.normalization_steps;
+#elif UDIV_NEEDS_NORMALIZATION
+               mp_limb_t x;
+
+               value <<= big_normalization_steps;
+               udiv_qrnnd (t[0], x, (mp_limb_t) (value >> 32),
+                           (mp_limb_t) value, big_base_norm);
+               t[1] = x >> big_normalization_steps;
+#else
+               udiv_qrnnd (t[0], t[1], (mp_limb_t) (value >> 32),
+                           (mp_limb_t) value, brec->big.base);
+#endif
+               n = 2;
+             }
+         }
+       else
+         {
+           t[0] = value;
+           n = 1;
+         }
+
+       /* Convert the 1-3 words in t[], word by word, to ASCII.  */
+       do
+         {
+           mp_limb_t ti = t[--n];
+           int ndig_for_this_limb = 0;
+
+#if UDIV_TIME > 2 * UMUL_TIME
+           mp_limb_t base_multiplier = brec->base_multiplier;
+           if (brec->flag)
+             while (ti != 0)
+               {
+                 mp_limb_t quo, rem, x, dummy;
+
+                 umul_ppmm (x, dummy, ti, base_multiplier);
+                 quo = (x + ((ti - x) >> 1)) >> (brec->post_shift - 1);
+                 rem = ti - quo * base;
+                 *--bp = digits[rem];
+                 ti = quo;
+                 ++ndig_for_this_limb;
+               }
+           else
+             while (ti != 0)
+               {
+                 mp_limb_t quo, rem, x, dummy;
+
+                 umul_ppmm (x, dummy, ti, base_multiplier);
+                 quo = x >> brec->post_shift;
+                 rem = ti - quo * base;
+                 *--bp = digits[rem];
+                 ti = quo;
+                 ++ndig_for_this_limb;
+               }
+#else
+           while (ti != 0)
+             {
+               mp_limb_t quo, rem;
+
+               quo = ti / base;
+               rem = ti % base;
+               *--bp = digits[rem];
+               ti = quo;
+               ++ndig_for_this_limb;
+             }
+#endif
+           /* If this wasn't the most significant word, pad with zeros.  */
+           if (n != 0)
+             while (ndig_for_this_limb < brec->big.ndigits)
+               {
+                 *--bp = '0';
+                 ++ndig_for_this_limb;
+               }
+         }
+       while (n != 0);
+#endif
+      }
+      break;
+    }
+
+  return bp;
+}