1 /* Private floating point rounding and exceptions handling. AArch64 version.
2 Copyright (C) 2014-2023 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 #ifndef AARCH64_FENV_PRIVATE_H
20 #define AARCH64_FENV_PRIVATE_H 1
21
22 #include <fenv.h>
23 #include <fpu_control.h>
24
25 static __always_inline void
26 libc_feholdexcept_aarch64 (fenv_t *envp)
27 {
28 fpu_control_t fpcr;
29 fpu_control_t new_fpcr;
30 fpu_fpsr_t fpsr;
31 fpu_fpsr_t new_fpsr;
32
33 _FPU_GETCW (fpcr);
34 _FPU_GETFPSR (fpsr);
35 envp->__fpcr = fpcr;
36 envp->__fpsr = fpsr;
37
38 /* Clear exception flags and set all exceptions to non-stop. */
39 new_fpcr = fpcr & ~(FE_ALL_EXCEPT << FE_EXCEPT_SHIFT);
40 new_fpsr = fpsr & ~FE_ALL_EXCEPT;
41
42 if (__glibc_unlikely (new_fpcr != fpcr))
43 _FPU_SETCW (new_fpcr);
44
45 if (new_fpsr != fpsr)
46 _FPU_SETFPSR (new_fpsr);
47 }
48
49 #define libc_feholdexcept libc_feholdexcept_aarch64
50 #define libc_feholdexceptf libc_feholdexcept_aarch64
51 #define libc_feholdexceptl libc_feholdexcept_aarch64
52
53 static __always_inline void
54 libc_fesetround_aarch64 (int round)
55 {
56 fpu_control_t fpcr;
57
58 _FPU_GETCW (fpcr);
59
60 /* Check whether rounding modes are different. */
61 round = (fpcr ^ round) & _FPU_FPCR_RM_MASK;
62
63 /* Set new rounding mode if different. */
64 if (__glibc_unlikely (round != 0))
65 _FPU_SETCW (fpcr ^ round);
66 }
67
68 #define libc_fesetround libc_fesetround_aarch64
69 #define libc_fesetroundf libc_fesetround_aarch64
70 #define libc_fesetroundl libc_fesetround_aarch64
71
72 static __always_inline void
73 libc_feholdexcept_setround_aarch64 (fenv_t *envp, int round)
74 {
75 fpu_control_t fpcr;
76 fpu_control_t new_fpcr;
77 fpu_fpsr_t fpsr;
78 fpu_fpsr_t new_fpsr;
79
80 _FPU_GETCW (fpcr);
81 _FPU_GETFPSR (fpsr);
82 envp->__fpcr = fpcr;
83 envp->__fpsr = fpsr;
84
85 /* Clear exception flags, set all exceptions to non-stop,
86 and set new rounding mode. */
87 new_fpcr = fpcr & ~((FE_ALL_EXCEPT << FE_EXCEPT_SHIFT) | _FPU_FPCR_RM_MASK);
88 new_fpcr |= round;
89 new_fpsr = fpsr & ~FE_ALL_EXCEPT;
90
91 if (__glibc_unlikely (new_fpcr != fpcr))
92 _FPU_SETCW (new_fpcr);
93
94 if (new_fpsr != fpsr)
95 _FPU_SETFPSR (new_fpsr);
96 }
97
98 #define libc_feholdexcept_setround libc_feholdexcept_setround_aarch64
99 #define libc_feholdexcept_setroundf libc_feholdexcept_setround_aarch64
100 #define libc_feholdexcept_setroundl libc_feholdexcept_setround_aarch64
101
102 static __always_inline int
103 libc_fetestexcept_aarch64 (int ex)
104 {
105 fpu_fpsr_t fpsr;
106
107 _FPU_GETFPSR (fpsr);
108 return fpsr & ex & FE_ALL_EXCEPT;
109 }
110
111 #define libc_fetestexcept libc_fetestexcept_aarch64
112 #define libc_fetestexceptf libc_fetestexcept_aarch64
113 #define libc_fetestexceptl libc_fetestexcept_aarch64
114
115 static __always_inline void
116 libc_fesetenv_aarch64 (const fenv_t *envp)
117 {
118 fpu_control_t fpcr;
119 fpu_control_t new_fpcr;
120
121 _FPU_GETCW (fpcr);
122 new_fpcr = envp->__fpcr;
123
124 if (__glibc_unlikely (fpcr != new_fpcr))
125 _FPU_SETCW (new_fpcr);
126
127 _FPU_SETFPSR (envp->__fpsr);
128 }
129
130 #define libc_fesetenv libc_fesetenv_aarch64
131 #define libc_fesetenvf libc_fesetenv_aarch64
132 #define libc_fesetenvl libc_fesetenv_aarch64
133 #define libc_feresetround_noex libc_fesetenv_aarch64
134 #define libc_feresetround_noexf libc_fesetenv_aarch64
135 #define libc_feresetround_noexl libc_fesetenv_aarch64
136
137 static __always_inline int
138 libc_feupdateenv_test_aarch64 (const fenv_t *envp, int ex)
139 {
140 fpu_control_t fpcr;
141 fpu_control_t new_fpcr;
142 fpu_fpsr_t fpsr;
143 fpu_fpsr_t new_fpsr;
144 int excepts;
145
146 _FPU_GETCW (fpcr);
147 _FPU_GETFPSR (fpsr);
148
149 /* Merge current exception flags with the saved fenv. */
150 excepts = fpsr & FE_ALL_EXCEPT;
151 new_fpcr = envp->__fpcr;
152 new_fpsr = envp->__fpsr | excepts;
153
154 if (__glibc_unlikely (fpcr != new_fpcr))
155 _FPU_SETCW (new_fpcr);
156
157 if (fpsr != new_fpsr)
158 _FPU_SETFPSR (new_fpsr);
159
160 /* Raise the exceptions if enabled in the new FP state. */
161 if (__glibc_unlikely (excepts & (new_fpcr >> FE_EXCEPT_SHIFT)))
162 __feraiseexcept (excepts);
163
164 return excepts & ex;
165 }
166
167 #define libc_feupdateenv_test libc_feupdateenv_test_aarch64
168 #define libc_feupdateenv_testf libc_feupdateenv_test_aarch64
169 #define libc_feupdateenv_testl libc_feupdateenv_test_aarch64
170
171 static __always_inline void
172 libc_feupdateenv_aarch64 (const fenv_t *envp)
173 {
174 libc_feupdateenv_test_aarch64 (envp, 0);
175 }
176
177 #define libc_feupdateenv libc_feupdateenv_aarch64
178 #define libc_feupdateenvf libc_feupdateenv_aarch64
179 #define libc_feupdateenvl libc_feupdateenv_aarch64
180
181 static __always_inline void
182 libc_feholdsetround_aarch64 (fenv_t *envp, int round)
183 {
184 fpu_control_t fpcr;
185 fpu_fpsr_t fpsr;
186
187 _FPU_GETCW (fpcr);
188 _FPU_GETFPSR (fpsr);
189 envp->__fpcr = fpcr;
190 envp->__fpsr = fpsr;
191
192 /* Check whether rounding modes are different. */
193 round = (fpcr ^ round) & _FPU_FPCR_RM_MASK;
194
195 /* Set new rounding mode if different. */
196 if (__glibc_unlikely (round != 0))
197 _FPU_SETCW (fpcr ^ round);
198 }
199
200 #define libc_feholdsetround libc_feholdsetround_aarch64
201 #define libc_feholdsetroundf libc_feholdsetround_aarch64
202 #define libc_feholdsetroundl libc_feholdsetround_aarch64
203
204 static __always_inline void
205 libc_feresetround_aarch64 (fenv_t *envp)
206 {
207 fpu_control_t fpcr;
208 int round;
209
210 _FPU_GETCW (fpcr);
211
212 /* Check whether rounding modes are different. */
213 round = (envp->__fpcr ^ fpcr) & _FPU_FPCR_RM_MASK;
214
215 /* Restore the rounding mode if it was changed. */
216 if (__glibc_unlikely (round != 0))
217 _FPU_SETCW (fpcr ^ round);
218 }
219
220 #define libc_feresetround libc_feresetround_aarch64
221 #define libc_feresetroundf libc_feresetround_aarch64
222 #define libc_feresetroundl libc_feresetround_aarch64
223
224 /* We have support for rounding mode context. */
225 #define HAVE_RM_CTX 1
226
227 static __always_inline void
228 libc_feholdsetround_aarch64_ctx (struct rm_ctx *ctx, int r)
229 {
230 fpu_control_t fpcr;
231 int round;
232
233 _FPU_GETCW (fpcr);
234 ctx->env.__fpcr = fpcr;
235
236 /* Check whether rounding modes are different. */
237 round = (fpcr ^ r) & _FPU_FPCR_RM_MASK;
238 ctx->updated_status = round != 0;
239
240 /* Set the rounding mode if changed. */
241 if (__glibc_unlikely (round != 0))
242 _FPU_SETCW (fpcr ^ round);
243 }
244
245 #define libc_feholdsetround_ctx libc_feholdsetround_aarch64_ctx
246 #define libc_feholdsetroundf_ctx libc_feholdsetround_aarch64_ctx
247 #define libc_feholdsetroundl_ctx libc_feholdsetround_aarch64_ctx
248
249 static __always_inline void
250 libc_feresetround_aarch64_ctx (struct rm_ctx *ctx)
251 {
252 /* Restore the rounding mode if updated. */
253 if (__glibc_unlikely (ctx->updated_status))
254 _FPU_SETCW (ctx->env.__fpcr);
255 }
256
257 #define libc_feresetround_ctx libc_feresetround_aarch64_ctx
258 #define libc_feresetroundf_ctx libc_feresetround_aarch64_ctx
259 #define libc_feresetroundl_ctx libc_feresetround_aarch64_ctx
260
261 static __always_inline void
262 libc_feholdsetround_noex_aarch64_ctx (struct rm_ctx *ctx, int r)
263 {
264 fpu_control_t fpcr;
265 fpu_fpsr_t fpsr;
266 int round;
267
268 _FPU_GETCW (fpcr);
269 _FPU_GETFPSR (fpsr);
270 ctx->env.__fpcr = fpcr;
271 ctx->env.__fpsr = fpsr;
272
273 /* Check whether rounding modes are different. */
274 round = (fpcr ^ r) & _FPU_FPCR_RM_MASK;
275 ctx->updated_status = round != 0;
276
277 /* Set the rounding mode if changed. */
278 if (__glibc_unlikely (round != 0))
279 _FPU_SETCW (fpcr ^ round);
280 }
281
282 #define libc_feholdsetround_noex_ctx libc_feholdsetround_noex_aarch64_ctx
283 #define libc_feholdsetround_noexf_ctx libc_feholdsetround_noex_aarch64_ctx
284 #define libc_feholdsetround_noexl_ctx libc_feholdsetround_noex_aarch64_ctx
285
286 static __always_inline void
287 libc_feresetround_noex_aarch64_ctx (struct rm_ctx *ctx)
288 {
289 /* Restore the rounding mode if updated. */
290 if (__glibc_unlikely (ctx->updated_status))
291 _FPU_SETCW (ctx->env.__fpcr);
292
293 /* Write new FPSR to restore exception flags. */
294 _FPU_SETFPSR (ctx->env.__fpsr);
295 }
296
297 #define libc_feresetround_noex_ctx libc_feresetround_noex_aarch64_ctx
298 #define libc_feresetround_noexf_ctx libc_feresetround_noex_aarch64_ctx
299 #define libc_feresetround_noexl_ctx libc_feresetround_noex_aarch64_ctx
300
301 #include_next <fenv_private.h>
302
303 #endif