q_feq.c

来自「glibc 库, 不仅可以学习使用库函数,还可以学习函数的具体实现,是提高功力的」· C语言 代码 · 共 41 行

/* Software floating-point emulation.
   Return 1 if a == b
   Copyright (C) 1997, 1999, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Richard Henderson ([e-mail]) and
		  Jakub Jelinek ([e-mail]).

   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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include "soft-fp.h"
#include "quad.h"

int _q_feq(const long double a, const long double b)
{
  FP_DECL_EX;
  FP_DECL_Q(A); FP_DECL_Q(B);
  int r;

  FP_UNPACK_RAW_Q(A, a);
  FP_UNPACK_RAW_Q(B, b);
  FP_CMP_EQ_Q(r, A, B);
  if (r && (FP_ISSIGNAN_Q(A) || FP_ISSIGNAN_Q(B)))
    FP_SET_EXCEPTION(FP_EX_INVALID);
  FP_HANDLE_EXCEPTIONS;

  return !r;
}