1 | /* Add _Float64 values, converting the result to _Float32x. i386 version. |
2 | Copyright (C) 2018-2022 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 | #include <math.h> |
20 | #include <fpu_control.h> |
21 | #include <math-narrow-eval.h> |
22 | #include <math-narrow.h> |
23 | |
24 | _Float32x |
25 | __f32xaddf64 (_Float64 x, _Float64 y) |
26 | { |
27 | /* To avoid double rounding, set double precision for the addition. |
28 | math_narrow_eval is still needed to eliminate excess range in the |
29 | case of overflow. If the result of the addition is in the |
30 | subnormal range for double, it is exact, so no issues of double |
31 | rounding for subnormals arise. */ |
32 | fpu_control_t cw, cw_double; |
33 | _FPU_GETCW (cw); |
34 | cw_double = (cw & ~_FPU_EXTENDED) | _FPU_DOUBLE; |
35 | _FPU_SETCW (cw_double); |
36 | _Float32x ret = math_narrow_eval (x + y); |
37 | _FPU_SETCW (cw); |
38 | CHECK_NARROW_ADD (ret, x, y); |
39 | return ret; |
40 | } |
41 | libm_alias_float32x_float64 (add) |
42 | |