xref: /reactos/sdk/lib/crt/math/libm_sse2/hypotf.c (revision e5993f13)
1 
2 /*******************************************************************************
3 MIT License
4 -----------
5 
6 Copyright (c) 2002-2019 Advanced Micro Devices, Inc.
7 
8 Permission is hereby granted, free of charge, to any person obtaining a copy
9 of this Software and associated documentaon files (the "Software"), to deal
10 in the Software without restriction, including without limitation the rights
11 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
12 copies of the Software, and to permit persons to whom the Software is
13 furnished to do so, subject to the following conditions:
14 
15 The above copyright notice and this permission notice shall be included in
16 all copies or substantial portions of the Software.
17 
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
21 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
22 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
24 THE SOFTWARE.
25 *******************************************************************************/
26 
27 #include "libm.h"
28 #include "libm_util.h"
29 
30 #ifdef USE_SOFTWARE_SQRT
31 #define USE_SQRTF_AMD_INLINE
32 #endif
33 #define USE_INFINITYF_WITH_FLAGS
34 #define USE_HANDLE_ERRORF
35 #include "libm_inlines.h"
36 #ifdef USE_SOFTWARE_SQRT
37 #undef USE_SQRTF_AMD_INLINE
38 #endif
39 #undef USE_INFINITYF_WITH_FLAGS
40 #undef USE_HANDLE_ERRORF
41 
42 #include "libm_errno.h"
43 
44 
45 float FN_PROTOTYPE(_hypotf)(float x, float y)
46 {
47   /* Returns sqrt(x*x + y*y) with no overflow or underflow unless
48      the result warrants it */
49 
50     /* Do intermediate computations in double precision
51        and use sqrt instruction from chip if available. */
52     double dx = x, dy = y, dr, retval;
53 
54     /* The largest finite float, stored as a double */
55     const double large = 3.40282346638528859812e+38; /* 0x47efffffe0000000 */
56 
57 
58   unsigned long long ux, uy, avx, avy;
59 
60   GET_BITS_DP64(x, avx);
61   avx &= ~SIGNBIT_DP64;
62   GET_BITS_DP64(y, avy);
63   avy &= ~SIGNBIT_DP64;
64   ux = (avx >> EXPSHIFTBITS_DP64);
65   uy = (avy >> EXPSHIFTBITS_DP64);
66 
67   if (ux == BIASEDEMAX_DP64 + 1 || uy == BIASEDEMAX_DP64 + 1)
68     {
69       retval = x*x + y*y;
70       /* One or both of the arguments are NaN or infinity. The
71          result will also be NaN or infinity. */
72       if (((ux == BIASEDEMAX_DP64 + 1) && !(avx & MANTBITS_DP64)) ||
73           ((uy == BIASEDEMAX_DP64 + 1) && !(avy & MANTBITS_DP64)))
74         /* x or y is infinity. ISO C99 defines that we must
75            return +infinity, even if the other argument is NaN.
76            Note that the computation of x*x + y*y above will already
77            have raised invalid if either x or y is a signalling NaN. */
78         return infinityf_with_flags(0);
79       else
80         /* One or both of x or y is NaN, and neither is infinity.
81            Raise invalid if it's a signalling NaN */
82         return (float)retval;
83     }
84 
85     dr = (dx*dx + dy*dy);
86 
87 #if USE_SOFTWARE_SQRT
88     retval = sqrtf_amd_inline(r);
89 #else
90   /* VC++ intrinsic call */
91   _mm_store_sd(&retval, _mm_sqrt_sd(_mm_setzero_pd(), _mm_load_sd(&dr)));
92 #endif
93 
94     if (retval > large)
95       return _handle_errorf("_hypotf", OP_HYPOT, PINFBITPATT_SP32, _OVERFLOW,
96                            AMD_F_OVERFLOW | AMD_F_INEXACT, ERANGE, x, y, 2);
97     else
98       return (float)retval;
99 }
100