1  /*
 2   * Copyright (C) 2008-2020 Advanced Micro Devices, Inc. All rights reserved.
 3   * Redistribution and use in source and binary forms, with or without modification,
 4   * are permitted provided that the following conditions are met:
 5   * 1. Redistributions of source code must retain the above copyright notice,
 6   *    this list of conditions and the following disclaimer.
 7   * 2. Redistributions in binary form must reproduce the above copyright notice,
 8   *    this list of conditions and the following disclaimer in the documentation
 9   *    and/or other materials provided with the distribution.
10   * 3. Neither the name of the copyright holder nor the names of its contributors
11   *    may be used to endorse or promote products derived from this software without
12   *    specific prior written permission.
13   *
14   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
15   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17   * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
18   * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
20   * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
21   * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
23   * POSSIBILITY OF SUCH DAMAGE.
24   *
25   */
26  
27  #include "libm_amd.h" 
28  #include "libm_util_amd.h" 
29  #include "libm_special.h" 
30   
31   
32  float FN_PROTOTYPE_REF(nexttowardf)(float x, long double y) 
33  { 
34   
35   
36      UT32 checkbits; 
37      long double dy = (long double) y; 
38      checkbits.f32=x; 
39   
40   
41   
42  	/* check if the number is nan */
43      if(((checkbits.u32 & ~SIGNBIT_SP32) > EXPBITS_SP32 ))
44      {
45  #ifdef WINDOWS
46  	return  __amd_handle_errorf("nexttoward", __amd_nexttoward, checkbits.u32| QNAN_MASK_32, _DOMAIN, AMD_F_NONE, EDOM, x, 0.0, 1);
47  #else
48  	if (checkbits.u32 & QNAN_MASK_32)
49  	return  __amd_handle_errorf("nexttoward", __amd_nexttoward, checkbits.u32| QNAN_MASK_32, _DOMAIN, AMD_F_NONE, EDOM, x, 0.0, 1);
50  	else
51  	return  __amd_handle_errorf("nexttoward", __amd_nexttoward, checkbits.u32| QNAN_MASK_32, _DOMAIN, AMD_F_INVALID, EDOM, x, 0.0, 1);
52  #endif
53      }
54  	 
55   
56      /* if x == y return y in the type of x */ 
57      if( x == dy ) 
58      { 
59          return (float) dy; 
60      } 
61   
62      if( x == 0.0) 
63      { 
64          checkbits.u32 = 1; 
65          if( dy > 0.0 ) 
66               return checkbits.f32; 
67          else 
68              return -checkbits.f32; 
69      } 
70   
71   
72      /* compute the next heigher or lower value */ 
73      if(((x>0.0F) ^ (dy>x)) == 0) 
74      { 
75          checkbits.u32++; 
76      } 
77      else 
78      { 
79          checkbits.u32--; 
80      } 
81   
82      /* check if the result is nan or inf */ 
83      if(((checkbits.u32 & ~SIGNBIT_SP32) >= EXPBITS_SP32 )) 
84      { 
85  		return  __amd_handle_errorf("nexttowardf", __amd_nexttoward, checkbits.u32 | QNAN_MASK_32, _DOMAIN,0, EDOM, x, 0.0, 1);
86      } 
87   
88      return checkbits.f32; 
89  } 
90