1/* Copyright (C) 1996-2026 Free Software Foundation, Inc.
2
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 License as
7 published by the Free Software Foundation; either version 2.1 of the
8 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#ifndef _AARCH64_FPU_CONTROL_H
20#define _AARCH64_FPU_CONTROL_H
21
22#include <features.h>
23#include <sys/types.h>
24
25/* Macros for accessing the FPCR and FPSR. */
26
27#if __GNUC_PREREQ (6,0)
28# define _FPU_GETCW(fpcr) (fpcr = __builtin_aarch64_get_fpcr ())
29# define _FPU_SETCW(fpcr) __builtin_aarch64_set_fpcr (fpcr)
30# define _FPU_GETFPSR(fpsr) (fpsr = __builtin_aarch64_get_fpsr ())
31# define _FPU_SETFPSR(fpsr) __builtin_aarch64_set_fpsr (fpsr)
32#else
33# define _FPU_GETCW(fpcr) \
34 ({ \
35 __uint64_t __fpcr; \
36 __asm__ __volatile__ ("mrs %0, fpcr" : "=r" (__fpcr)); \
37 fpcr = __fpcr; \
38 })
39
40# define _FPU_SETCW(fpcr) \
41 ({ \
42 __uint64_t __fpcr = fpcr; \
43 __asm__ __volatile__ ("msr fpcr, %0" : : "r" (__fpcr)); \
44 })
45
46# define _FPU_GETFPSR(fpsr) \
47 ({ \
48 __uint64_t __fpsr; \
49 __asm__ __volatile__ ("mrs %0, fpsr" : "=r" (__fpsr)); \
50 fpsr = __fpsr; \
51 })
52
53# define _FPU_SETFPSR(fpsr) \
54 ({ \
55 __uint64_t __fpsr = fpsr; \
56 __asm__ __volatile__ ("msr fpsr, %0" : : "r" (__fpsr)); \
57 })
58#endif
59
60/* Reserved bits should be preserved when modifying register
61 contents. These two masks indicate which bits in each of FPCR and
62 FPSR should not be changed. */
63
64#define _FPU_RESERVED 0xfe0fe0f8
65#define _FPU_FPSR_RESERVED 0x0fffffe0
66
67#define _FPU_DEFAULT 0x00000000
68#define _FPU_FPSR_DEFAULT 0x00000000
69
70/* Layout of FPCR and FPSR:
71
72 | | | | | | | |
73 0 0 0 0 1 1 1 0 0 0 0 0 1 0 0 0 1 1 1 0 0 0 0 0 1 1 1 0 0 0 0 0
74 s s s s s s s s s s s
75 c c c c c c c c c c c c
76 N Z C V Q A D F R R S S S L L L I U U I U O D I I U U I U O D I
77 C H N Z M M T T B E E E D N N X F F Z O D N N X F F Z O
78 P O O R R Z N N N E K K E E E E E C K K C C C C C
79 D D I I P
80 E E D D
81 E E
82 */
83
84#define _FPU_FPCR_RM_MASK 0xc00000
85
86#define _FPU_FPCR_MASK_IXE 0x1000
87#define _FPU_FPCR_MASK_UFE 0x0800
88#define _FPU_FPCR_MASK_OFE 0x0400
89#define _FPU_FPCR_MASK_DZE 0x0200
90#define _FPU_FPCR_MASK_IOE 0x0100
91
92#define _FPU_FPCR_IEEE \
93 (_FPU_DEFAULT | _FPU_FPCR_MASK_IXE \
94 | _FPU_FPCR_MASK_UFE | _FPU_FPCR_MASK_OFE \
95 | _FPU_FPCR_MASK_DZE | _FPU_FPCR_MASK_IOE)
96
97#define _FPU_FPSR_IEEE 0
98
99typedef unsigned int fpu_control_t;
100typedef unsigned int fpu_fpsr_t;
101
102/* Default control word set at startup. */
103extern fpu_control_t __fpu_control;
104
105#endif