sysdeps/ieee754/soft-fp/s_fdiv.c

   1 /* Divide double values, narrowing the result to float, using soft-fp.
   2    Copyright (C) 2018-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #define f32divf64 __hide_f32divf64
  20 #define f32divf32x __hide_f32divf32x
  21 #define fdivl __hide_fdivl
  22 #include <math.h>
  23 #undef f32divf64
  24 #undef f32divf32x
  25 #undef fdivl
  26
  27 #include <math-narrow.h>
  28 #include <libc-diag.h>
  29
  30 /* R_f[01] are not set in cases where they are not used in packing,
  31    but the compiler does not see that they are set in all cases where
  32    they are used, resulting in warnings that they may be used
  33    uninitialized.  The location of the warning differs in different
  34    versions of GCC, it may be where R is defined using a macro or it
  35    may be where the macro is defined.  This happens only with -O1.  */
  36 DIAG_PUSH_NEEDS_COMMENT;
  37 DIAG_IGNORE_NEEDS_COMMENT (8, "-Wmaybe-uninitialized");
  38 #include <soft-fp.h>
  39 #include <single.h>
  40 #include <double.h>
  41
  42 float
  43 __fdiv (double x, double y)
  44 {
  45   FP_DECL_EX;
  46   FP_DECL_D (X);
  47   FP_DECL_D (Y);
  48   FP_DECL_D (R);
  49   FP_DECL_S (RN);
  50   float ret;
  51
  52   FP_INIT_ROUNDMODE;
  53   FP_UNPACK_D (X, x);
  54   FP_UNPACK_D (Y, y);
  55   FP_DIV_D (R, X, Y);
  56 #if _FP_W_TYPE_SIZE < _FP_FRACBITS_D
  57   FP_TRUNC_COOKED (S, D, 1, 2, RN, R);
  58 #else
  59   FP_TRUNC_COOKED (S, D, 1, 1, RN, R);
  60 #endif
  61   FP_PACK_S (ret, RN);
  62   FP_HANDLE_EXCEPTIONS;
  63   CHECK_NARROW_DIV (ret, x, y);
  64   return ret;
  65 }
  66 DIAG_POP_NEEDS_COMMENT;
  67
  68 libm_alias_float_double (div)