xref: /openbmc/qemu/target/arm/vfp_helper.c (revision 719f0f60)
1 /*
2  * ARM VFP floating-point operations
3  *
4  *  Copyright (c) 2003 Fabrice Bellard
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "exec/helper-proto.h"
23 #include "internals.h"
24 #ifdef CONFIG_TCG
25 #include "qemu/log.h"
26 #include "fpu/softfloat.h"
27 #endif
28 
29 /* VFP support.  We follow the convention used for VFP instructions:
30    Single precision routines have a "s" suffix, double precision a
31    "d" suffix.  */
32 
33 #ifdef CONFIG_TCG
34 
35 /* Convert host exception flags to vfp form.  */
36 static inline int vfp_exceptbits_from_host(int host_bits)
37 {
38     int target_bits = 0;
39 
40     if (host_bits & float_flag_invalid) {
41         target_bits |= 1;
42     }
43     if (host_bits & float_flag_divbyzero) {
44         target_bits |= 2;
45     }
46     if (host_bits & float_flag_overflow) {
47         target_bits |= 4;
48     }
49     if (host_bits & (float_flag_underflow | float_flag_output_denormal)) {
50         target_bits |= 8;
51     }
52     if (host_bits & float_flag_inexact) {
53         target_bits |= 0x10;
54     }
55     if (host_bits & float_flag_input_denormal) {
56         target_bits |= 0x80;
57     }
58     return target_bits;
59 }
60 
61 /* Convert vfp exception flags to target form.  */
62 static inline int vfp_exceptbits_to_host(int target_bits)
63 {
64     int host_bits = 0;
65 
66     if (target_bits & 1) {
67         host_bits |= float_flag_invalid;
68     }
69     if (target_bits & 2) {
70         host_bits |= float_flag_divbyzero;
71     }
72     if (target_bits & 4) {
73         host_bits |= float_flag_overflow;
74     }
75     if (target_bits & 8) {
76         host_bits |= float_flag_underflow;
77     }
78     if (target_bits & 0x10) {
79         host_bits |= float_flag_inexact;
80     }
81     if (target_bits & 0x80) {
82         host_bits |= float_flag_input_denormal;
83     }
84     return host_bits;
85 }
86 
87 static uint32_t vfp_get_fpscr_from_host(CPUARMState *env)
88 {
89     uint32_t i;
90 
91     i = get_float_exception_flags(&env->vfp.fp_status);
92     i |= get_float_exception_flags(&env->vfp.standard_fp_status);
93     /* FZ16 does not generate an input denormal exception.  */
94     i |= (get_float_exception_flags(&env->vfp.fp_status_f16)
95           & ~float_flag_input_denormal);
96     i |= (get_float_exception_flags(&env->vfp.standard_fp_status_f16)
97           & ~float_flag_input_denormal);
98     return vfp_exceptbits_from_host(i);
99 }
100 
101 static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val)
102 {
103     int i;
104     uint32_t changed = env->vfp.xregs[ARM_VFP_FPSCR];
105 
106     changed ^= val;
107     if (changed & (3 << 22)) {
108         i = (val >> 22) & 3;
109         switch (i) {
110         case FPROUNDING_TIEEVEN:
111             i = float_round_nearest_even;
112             break;
113         case FPROUNDING_POSINF:
114             i = float_round_up;
115             break;
116         case FPROUNDING_NEGINF:
117             i = float_round_down;
118             break;
119         case FPROUNDING_ZERO:
120             i = float_round_to_zero;
121             break;
122         }
123         set_float_rounding_mode(i, &env->vfp.fp_status);
124         set_float_rounding_mode(i, &env->vfp.fp_status_f16);
125     }
126     if (changed & FPCR_FZ16) {
127         bool ftz_enabled = val & FPCR_FZ16;
128         set_flush_to_zero(ftz_enabled, &env->vfp.fp_status_f16);
129         set_flush_to_zero(ftz_enabled, &env->vfp.standard_fp_status_f16);
130         set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status_f16);
131         set_flush_inputs_to_zero(ftz_enabled, &env->vfp.standard_fp_status_f16);
132     }
133     if (changed & FPCR_FZ) {
134         bool ftz_enabled = val & FPCR_FZ;
135         set_flush_to_zero(ftz_enabled, &env->vfp.fp_status);
136         set_flush_inputs_to_zero(ftz_enabled, &env->vfp.fp_status);
137     }
138     if (changed & FPCR_DN) {
139         bool dnan_enabled = val & FPCR_DN;
140         set_default_nan_mode(dnan_enabled, &env->vfp.fp_status);
141         set_default_nan_mode(dnan_enabled, &env->vfp.fp_status_f16);
142     }
143 
144     /*
145      * The exception flags are ORed together when we read fpscr so we
146      * only need to preserve the current state in one of our
147      * float_status values.
148      */
149     i = vfp_exceptbits_to_host(val);
150     set_float_exception_flags(i, &env->vfp.fp_status);
151     set_float_exception_flags(0, &env->vfp.fp_status_f16);
152     set_float_exception_flags(0, &env->vfp.standard_fp_status);
153     set_float_exception_flags(0, &env->vfp.standard_fp_status_f16);
154 }
155 
156 #else
157 
158 static uint32_t vfp_get_fpscr_from_host(CPUARMState *env)
159 {
160     return 0;
161 }
162 
163 static void vfp_set_fpscr_to_host(CPUARMState *env, uint32_t val)
164 {
165 }
166 
167 #endif
168 
169 uint32_t HELPER(vfp_get_fpscr)(CPUARMState *env)
170 {
171     uint32_t i, fpscr;
172 
173     fpscr = env->vfp.xregs[ARM_VFP_FPSCR]
174             | (env->vfp.vec_len << 16)
175             | (env->vfp.vec_stride << 20);
176 
177     /*
178      * M-profile LTPSIZE overlaps A-profile Stride; whichever of the
179      * two is not applicable to this CPU will always be zero.
180      */
181     fpscr |= env->v7m.ltpsize << 16;
182 
183     fpscr |= vfp_get_fpscr_from_host(env);
184 
185     i = env->vfp.qc[0] | env->vfp.qc[1] | env->vfp.qc[2] | env->vfp.qc[3];
186     fpscr |= i ? FPCR_QC : 0;
187 
188     return fpscr;
189 }
190 
191 uint32_t vfp_get_fpscr(CPUARMState *env)
192 {
193     return HELPER(vfp_get_fpscr)(env);
194 }
195 
196 void HELPER(vfp_set_fpscr)(CPUARMState *env, uint32_t val)
197 {
198     ARMCPU *cpu = env_archcpu(env);
199 
200     /* When ARMv8.2-FP16 is not supported, FZ16 is RES0.  */
201     if (!cpu_isar_feature(any_fp16, cpu)) {
202         val &= ~FPCR_FZ16;
203     }
204 
205     vfp_set_fpscr_to_host(env, val);
206 
207     if (!arm_feature(env, ARM_FEATURE_M)) {
208         /*
209          * Short-vector length and stride; on M-profile these bits
210          * are used for different purposes.
211          * We can't make this conditional be "if MVFR0.FPShVec != 0",
212          * because in v7A no-short-vector-support cores still had to
213          * allow Stride/Len to be written with the only effect that
214          * some insns are required to UNDEF if the guest sets them.
215          */
216         env->vfp.vec_len = extract32(val, 16, 3);
217         env->vfp.vec_stride = extract32(val, 20, 2);
218     } else if (cpu_isar_feature(aa32_mve, cpu)) {
219         env->v7m.ltpsize = extract32(val, FPCR_LTPSIZE_SHIFT,
220                                      FPCR_LTPSIZE_LENGTH);
221     }
222 
223     if (arm_feature(env, ARM_FEATURE_NEON)) {
224         /*
225          * The bit we set within fpscr_q is arbitrary; the register as a
226          * whole being zero/non-zero is what counts.
227          * TODO: M-profile MVE also has a QC bit.
228          */
229         env->vfp.qc[0] = val & FPCR_QC;
230         env->vfp.qc[1] = 0;
231         env->vfp.qc[2] = 0;
232         env->vfp.qc[3] = 0;
233     }
234 
235     /*
236      * We don't implement trapped exception handling, so the
237      * trap enable bits, IDE|IXE|UFE|OFE|DZE|IOE are all RAZ/WI (not RES0!)
238      *
239      * The exception flags IOC|DZC|OFC|UFC|IXC|IDC are stored in
240      * fp_status; QC, Len and Stride are stored separately earlier.
241      * Clear out all of those and the RES0 bits: only NZCV, AHP, DN,
242      * FZ, RMode and FZ16 are kept in vfp.xregs[FPSCR].
243      */
244     env->vfp.xregs[ARM_VFP_FPSCR] = val & 0xf7c80000;
245 }
246 
247 void vfp_set_fpscr(CPUARMState *env, uint32_t val)
248 {
249     HELPER(vfp_set_fpscr)(env, val);
250 }
251 
252 #ifdef CONFIG_TCG
253 
254 #define VFP_HELPER(name, p) HELPER(glue(glue(vfp_,name),p))
255 
256 #define VFP_BINOP(name) \
257 dh_ctype_f16 VFP_HELPER(name, h)(dh_ctype_f16 a, dh_ctype_f16 b, void *fpstp) \
258 { \
259     float_status *fpst = fpstp; \
260     return float16_ ## name(a, b, fpst); \
261 } \
262 float32 VFP_HELPER(name, s)(float32 a, float32 b, void *fpstp) \
263 { \
264     float_status *fpst = fpstp; \
265     return float32_ ## name(a, b, fpst); \
266 } \
267 float64 VFP_HELPER(name, d)(float64 a, float64 b, void *fpstp) \
268 { \
269     float_status *fpst = fpstp; \
270     return float64_ ## name(a, b, fpst); \
271 }
272 VFP_BINOP(add)
273 VFP_BINOP(sub)
274 VFP_BINOP(mul)
275 VFP_BINOP(div)
276 VFP_BINOP(min)
277 VFP_BINOP(max)
278 VFP_BINOP(minnum)
279 VFP_BINOP(maxnum)
280 #undef VFP_BINOP
281 
282 dh_ctype_f16 VFP_HELPER(neg, h)(dh_ctype_f16 a)
283 {
284     return float16_chs(a);
285 }
286 
287 float32 VFP_HELPER(neg, s)(float32 a)
288 {
289     return float32_chs(a);
290 }
291 
292 float64 VFP_HELPER(neg, d)(float64 a)
293 {
294     return float64_chs(a);
295 }
296 
297 dh_ctype_f16 VFP_HELPER(abs, h)(dh_ctype_f16 a)
298 {
299     return float16_abs(a);
300 }
301 
302 float32 VFP_HELPER(abs, s)(float32 a)
303 {
304     return float32_abs(a);
305 }
306 
307 float64 VFP_HELPER(abs, d)(float64 a)
308 {
309     return float64_abs(a);
310 }
311 
312 dh_ctype_f16 VFP_HELPER(sqrt, h)(dh_ctype_f16 a, CPUARMState *env)
313 {
314     return float16_sqrt(a, &env->vfp.fp_status_f16);
315 }
316 
317 float32 VFP_HELPER(sqrt, s)(float32 a, CPUARMState *env)
318 {
319     return float32_sqrt(a, &env->vfp.fp_status);
320 }
321 
322 float64 VFP_HELPER(sqrt, d)(float64 a, CPUARMState *env)
323 {
324     return float64_sqrt(a, &env->vfp.fp_status);
325 }
326 
327 static void softfloat_to_vfp_compare(CPUARMState *env, FloatRelation cmp)
328 {
329     uint32_t flags;
330     switch (cmp) {
331     case float_relation_equal:
332         flags = 0x6;
333         break;
334     case float_relation_less:
335         flags = 0x8;
336         break;
337     case float_relation_greater:
338         flags = 0x2;
339         break;
340     case float_relation_unordered:
341         flags = 0x3;
342         break;
343     default:
344         g_assert_not_reached();
345     }
346     env->vfp.xregs[ARM_VFP_FPSCR] =
347         deposit32(env->vfp.xregs[ARM_VFP_FPSCR], 28, 4, flags);
348 }
349 
350 /* XXX: check quiet/signaling case */
351 #define DO_VFP_cmp(P, FLOATTYPE, ARGTYPE, FPST) \
352 void VFP_HELPER(cmp, P)(ARGTYPE a, ARGTYPE b, CPUARMState *env)  \
353 { \
354     softfloat_to_vfp_compare(env, \
355         FLOATTYPE ## _compare_quiet(a, b, &env->vfp.FPST)); \
356 } \
357 void VFP_HELPER(cmpe, P)(ARGTYPE a, ARGTYPE b, CPUARMState *env) \
358 { \
359     softfloat_to_vfp_compare(env, \
360         FLOATTYPE ## _compare(a, b, &env->vfp.FPST)); \
361 }
362 DO_VFP_cmp(h, float16, dh_ctype_f16, fp_status_f16)
363 DO_VFP_cmp(s, float32, float32, fp_status)
364 DO_VFP_cmp(d, float64, float64, fp_status)
365 #undef DO_VFP_cmp
366 
367 /* Integer to float and float to integer conversions */
368 
369 #define CONV_ITOF(name, ftype, fsz, sign)                           \
370 ftype HELPER(name)(uint32_t x, void *fpstp)                         \
371 {                                                                   \
372     float_status *fpst = fpstp;                                     \
373     return sign##int32_to_##float##fsz((sign##int32_t)x, fpst);     \
374 }
375 
376 #define CONV_FTOI(name, ftype, fsz, sign, round)                \
377 sign##int32_t HELPER(name)(ftype x, void *fpstp)                \
378 {                                                               \
379     float_status *fpst = fpstp;                                 \
380     if (float##fsz##_is_any_nan(x)) {                           \
381         float_raise(float_flag_invalid, fpst);                  \
382         return 0;                                               \
383     }                                                           \
384     return float##fsz##_to_##sign##int32##round(x, fpst);       \
385 }
386 
387 #define FLOAT_CONVS(name, p, ftype, fsz, sign)            \
388     CONV_ITOF(vfp_##name##to##p, ftype, fsz, sign)        \
389     CONV_FTOI(vfp_to##name##p, ftype, fsz, sign, )        \
390     CONV_FTOI(vfp_to##name##z##p, ftype, fsz, sign, _round_to_zero)
391 
392 FLOAT_CONVS(si, h, uint32_t, 16, )
393 FLOAT_CONVS(si, s, float32, 32, )
394 FLOAT_CONVS(si, d, float64, 64, )
395 FLOAT_CONVS(ui, h, uint32_t, 16, u)
396 FLOAT_CONVS(ui, s, float32, 32, u)
397 FLOAT_CONVS(ui, d, float64, 64, u)
398 
399 #undef CONV_ITOF
400 #undef CONV_FTOI
401 #undef FLOAT_CONVS
402 
403 /* floating point conversion */
404 float64 VFP_HELPER(fcvtd, s)(float32 x, CPUARMState *env)
405 {
406     return float32_to_float64(x, &env->vfp.fp_status);
407 }
408 
409 float32 VFP_HELPER(fcvts, d)(float64 x, CPUARMState *env)
410 {
411     return float64_to_float32(x, &env->vfp.fp_status);
412 }
413 
414 uint32_t HELPER(bfcvt)(float32 x, void *status)
415 {
416     return float32_to_bfloat16(x, status);
417 }
418 
419 uint32_t HELPER(bfcvt_pair)(uint64_t pair, void *status)
420 {
421     bfloat16 lo = float32_to_bfloat16(extract64(pair, 0, 32), status);
422     bfloat16 hi = float32_to_bfloat16(extract64(pair, 32, 32), status);
423     return deposit32(lo, 16, 16, hi);
424 }
425 
426 /*
427  * VFP3 fixed point conversion. The AArch32 versions of fix-to-float
428  * must always round-to-nearest; the AArch64 ones honour the FPSCR
429  * rounding mode. (For AArch32 Neon the standard-FPSCR is set to
430  * round-to-nearest so either helper will work.) AArch32 float-to-fix
431  * must round-to-zero.
432  */
433 #define VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype)            \
434 ftype HELPER(vfp_##name##to##p)(uint##isz##_t  x, uint32_t shift,      \
435                                      void *fpstp) \
436 { return itype##_to_##float##fsz##_scalbn(x, -shift, fpstp); }
437 
438 #define VFP_CONV_FIX_FLOAT_ROUND(name, p, fsz, ftype, isz, itype)      \
439     ftype HELPER(vfp_##name##to##p##_round_to_nearest)(uint##isz##_t  x, \
440                                                      uint32_t shift,   \
441                                                      void *fpstp)      \
442     {                                                                  \
443         ftype ret;                                                     \
444         float_status *fpst = fpstp;                                    \
445         FloatRoundMode oldmode = fpst->float_rounding_mode;            \
446         fpst->float_rounding_mode = float_round_nearest_even;          \
447         ret = itype##_to_##float##fsz##_scalbn(x, -shift, fpstp);      \
448         fpst->float_rounding_mode = oldmode;                           \
449         return ret;                                                    \
450     }
451 
452 #define VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype, ROUND, suff) \
453 uint##isz##_t HELPER(vfp_to##name##p##suff)(ftype x, uint32_t shift,      \
454                                             void *fpst)                   \
455 {                                                                         \
456     if (unlikely(float##fsz##_is_any_nan(x))) {                           \
457         float_raise(float_flag_invalid, fpst);                            \
458         return 0;                                                         \
459     }                                                                     \
460     return float##fsz##_to_##itype##_scalbn(x, ROUND, shift, fpst);       \
461 }
462 
463 #define VFP_CONV_FIX(name, p, fsz, ftype, isz, itype)            \
464 VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype)              \
465 VFP_CONV_FIX_FLOAT_ROUND(name, p, fsz, ftype, isz, itype)        \
466 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype,        \
467                          float_round_to_zero, _round_to_zero)    \
468 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype,        \
469                          get_float_rounding_mode(fpst), )
470 
471 #define VFP_CONV_FIX_A64(name, p, fsz, ftype, isz, itype)        \
472 VFP_CONV_FIX_FLOAT(name, p, fsz, ftype, isz, itype)              \
473 VFP_CONV_FLOAT_FIX_ROUND(name, p, fsz, ftype, isz, itype,        \
474                          get_float_rounding_mode(fpst), )
475 
476 VFP_CONV_FIX(sh, d, 64, float64, 64, int16)
477 VFP_CONV_FIX(sl, d, 64, float64, 64, int32)
478 VFP_CONV_FIX_A64(sq, d, 64, float64, 64, int64)
479 VFP_CONV_FIX(uh, d, 64, float64, 64, uint16)
480 VFP_CONV_FIX(ul, d, 64, float64, 64, uint32)
481 VFP_CONV_FIX_A64(uq, d, 64, float64, 64, uint64)
482 VFP_CONV_FIX(sh, s, 32, float32, 32, int16)
483 VFP_CONV_FIX(sl, s, 32, float32, 32, int32)
484 VFP_CONV_FIX_A64(sq, s, 32, float32, 64, int64)
485 VFP_CONV_FIX(uh, s, 32, float32, 32, uint16)
486 VFP_CONV_FIX(ul, s, 32, float32, 32, uint32)
487 VFP_CONV_FIX_A64(uq, s, 32, float32, 64, uint64)
488 VFP_CONV_FIX(sh, h, 16, dh_ctype_f16, 32, int16)
489 VFP_CONV_FIX(sl, h, 16, dh_ctype_f16, 32, int32)
490 VFP_CONV_FIX_A64(sq, h, 16, dh_ctype_f16, 64, int64)
491 VFP_CONV_FIX(uh, h, 16, dh_ctype_f16, 32, uint16)
492 VFP_CONV_FIX(ul, h, 16, dh_ctype_f16, 32, uint32)
493 VFP_CONV_FIX_A64(uq, h, 16, dh_ctype_f16, 64, uint64)
494 
495 #undef VFP_CONV_FIX
496 #undef VFP_CONV_FIX_FLOAT
497 #undef VFP_CONV_FLOAT_FIX_ROUND
498 #undef VFP_CONV_FIX_A64
499 
500 /* Set the current fp rounding mode and return the old one.
501  * The argument is a softfloat float_round_ value.
502  */
503 uint32_t HELPER(set_rmode)(uint32_t rmode, void *fpstp)
504 {
505     float_status *fp_status = fpstp;
506 
507     uint32_t prev_rmode = get_float_rounding_mode(fp_status);
508     set_float_rounding_mode(rmode, fp_status);
509 
510     return prev_rmode;
511 }
512 
513 /* Half precision conversions.  */
514 float32 HELPER(vfp_fcvt_f16_to_f32)(uint32_t a, void *fpstp, uint32_t ahp_mode)
515 {
516     /* Squash FZ16 to 0 for the duration of conversion.  In this case,
517      * it would affect flushing input denormals.
518      */
519     float_status *fpst = fpstp;
520     bool save = get_flush_inputs_to_zero(fpst);
521     set_flush_inputs_to_zero(false, fpst);
522     float32 r = float16_to_float32(a, !ahp_mode, fpst);
523     set_flush_inputs_to_zero(save, fpst);
524     return r;
525 }
526 
527 uint32_t HELPER(vfp_fcvt_f32_to_f16)(float32 a, void *fpstp, uint32_t ahp_mode)
528 {
529     /* Squash FZ16 to 0 for the duration of conversion.  In this case,
530      * it would affect flushing output denormals.
531      */
532     float_status *fpst = fpstp;
533     bool save = get_flush_to_zero(fpst);
534     set_flush_to_zero(false, fpst);
535     float16 r = float32_to_float16(a, !ahp_mode, fpst);
536     set_flush_to_zero(save, fpst);
537     return r;
538 }
539 
540 float64 HELPER(vfp_fcvt_f16_to_f64)(uint32_t a, void *fpstp, uint32_t ahp_mode)
541 {
542     /* Squash FZ16 to 0 for the duration of conversion.  In this case,
543      * it would affect flushing input denormals.
544      */
545     float_status *fpst = fpstp;
546     bool save = get_flush_inputs_to_zero(fpst);
547     set_flush_inputs_to_zero(false, fpst);
548     float64 r = float16_to_float64(a, !ahp_mode, fpst);
549     set_flush_inputs_to_zero(save, fpst);
550     return r;
551 }
552 
553 uint32_t HELPER(vfp_fcvt_f64_to_f16)(float64 a, void *fpstp, uint32_t ahp_mode)
554 {
555     /* Squash FZ16 to 0 for the duration of conversion.  In this case,
556      * it would affect flushing output denormals.
557      */
558     float_status *fpst = fpstp;
559     bool save = get_flush_to_zero(fpst);
560     set_flush_to_zero(false, fpst);
561     float16 r = float64_to_float16(a, !ahp_mode, fpst);
562     set_flush_to_zero(save, fpst);
563     return r;
564 }
565 
566 /* NEON helpers.  */
567 
568 /* Constants 256 and 512 are used in some helpers; we avoid relying on
569  * int->float conversions at run-time.  */
570 #define float64_256 make_float64(0x4070000000000000LL)
571 #define float64_512 make_float64(0x4080000000000000LL)
572 #define float16_maxnorm make_float16(0x7bff)
573 #define float32_maxnorm make_float32(0x7f7fffff)
574 #define float64_maxnorm make_float64(0x7fefffffffffffffLL)
575 
576 /* Reciprocal functions
577  *
578  * The algorithm that must be used to calculate the estimate
579  * is specified by the ARM ARM, see FPRecipEstimate()/RecipEstimate
580  */
581 
582 /* See RecipEstimate()
583  *
584  * input is a 9 bit fixed point number
585  * input range 256 .. 511 for a number from 0.5 <= x < 1.0.
586  * result range 256 .. 511 for a number from 1.0 to 511/256.
587  */
588 
589 static int recip_estimate(int input)
590 {
591     int a, b, r;
592     assert(256 <= input && input < 512);
593     a = (input * 2) + 1;
594     b = (1 << 19) / a;
595     r = (b + 1) >> 1;
596     assert(256 <= r && r < 512);
597     return r;
598 }
599 
600 /*
601  * Common wrapper to call recip_estimate
602  *
603  * The parameters are exponent and 64 bit fraction (without implicit
604  * bit) where the binary point is nominally at bit 52. Returns a
605  * float64 which can then be rounded to the appropriate size by the
606  * callee.
607  */
608 
609 static uint64_t call_recip_estimate(int *exp, int exp_off, uint64_t frac)
610 {
611     uint32_t scaled, estimate;
612     uint64_t result_frac;
613     int result_exp;
614 
615     /* Handle sub-normals */
616     if (*exp == 0) {
617         if (extract64(frac, 51, 1) == 0) {
618             *exp = -1;
619             frac <<= 2;
620         } else {
621             frac <<= 1;
622         }
623     }
624 
625     /* scaled = UInt('1':fraction<51:44>) */
626     scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8));
627     estimate = recip_estimate(scaled);
628 
629     result_exp = exp_off - *exp;
630     result_frac = deposit64(0, 44, 8, estimate);
631     if (result_exp == 0) {
632         result_frac = deposit64(result_frac >> 1, 51, 1, 1);
633     } else if (result_exp == -1) {
634         result_frac = deposit64(result_frac >> 2, 50, 2, 1);
635         result_exp = 0;
636     }
637 
638     *exp = result_exp;
639 
640     return result_frac;
641 }
642 
643 static bool round_to_inf(float_status *fpst, bool sign_bit)
644 {
645     switch (fpst->float_rounding_mode) {
646     case float_round_nearest_even: /* Round to Nearest */
647         return true;
648     case float_round_up: /* Round to +Inf */
649         return !sign_bit;
650     case float_round_down: /* Round to -Inf */
651         return sign_bit;
652     case float_round_to_zero: /* Round to Zero */
653         return false;
654     default:
655         g_assert_not_reached();
656     }
657 }
658 
659 uint32_t HELPER(recpe_f16)(uint32_t input, void *fpstp)
660 {
661     float_status *fpst = fpstp;
662     float16 f16 = float16_squash_input_denormal(input, fpst);
663     uint32_t f16_val = float16_val(f16);
664     uint32_t f16_sign = float16_is_neg(f16);
665     int f16_exp = extract32(f16_val, 10, 5);
666     uint32_t f16_frac = extract32(f16_val, 0, 10);
667     uint64_t f64_frac;
668 
669     if (float16_is_any_nan(f16)) {
670         float16 nan = f16;
671         if (float16_is_signaling_nan(f16, fpst)) {
672             float_raise(float_flag_invalid, fpst);
673             nan = float16_silence_nan(f16, fpst);
674         }
675         if (fpst->default_nan_mode) {
676             nan =  float16_default_nan(fpst);
677         }
678         return nan;
679     } else if (float16_is_infinity(f16)) {
680         return float16_set_sign(float16_zero, float16_is_neg(f16));
681     } else if (float16_is_zero(f16)) {
682         float_raise(float_flag_divbyzero, fpst);
683         return float16_set_sign(float16_infinity, float16_is_neg(f16));
684     } else if (float16_abs(f16) < (1 << 8)) {
685         /* Abs(value) < 2.0^-16 */
686         float_raise(float_flag_overflow | float_flag_inexact, fpst);
687         if (round_to_inf(fpst, f16_sign)) {
688             return float16_set_sign(float16_infinity, f16_sign);
689         } else {
690             return float16_set_sign(float16_maxnorm, f16_sign);
691         }
692     } else if (f16_exp >= 29 && fpst->flush_to_zero) {
693         float_raise(float_flag_underflow, fpst);
694         return float16_set_sign(float16_zero, float16_is_neg(f16));
695     }
696 
697     f64_frac = call_recip_estimate(&f16_exp, 29,
698                                    ((uint64_t) f16_frac) << (52 - 10));
699 
700     /* result = sign : result_exp<4:0> : fraction<51:42> */
701     f16_val = deposit32(0, 15, 1, f16_sign);
702     f16_val = deposit32(f16_val, 10, 5, f16_exp);
703     f16_val = deposit32(f16_val, 0, 10, extract64(f64_frac, 52 - 10, 10));
704     return make_float16(f16_val);
705 }
706 
707 float32 HELPER(recpe_f32)(float32 input, void *fpstp)
708 {
709     float_status *fpst = fpstp;
710     float32 f32 = float32_squash_input_denormal(input, fpst);
711     uint32_t f32_val = float32_val(f32);
712     bool f32_sign = float32_is_neg(f32);
713     int f32_exp = extract32(f32_val, 23, 8);
714     uint32_t f32_frac = extract32(f32_val, 0, 23);
715     uint64_t f64_frac;
716 
717     if (float32_is_any_nan(f32)) {
718         float32 nan = f32;
719         if (float32_is_signaling_nan(f32, fpst)) {
720             float_raise(float_flag_invalid, fpst);
721             nan = float32_silence_nan(f32, fpst);
722         }
723         if (fpst->default_nan_mode) {
724             nan =  float32_default_nan(fpst);
725         }
726         return nan;
727     } else if (float32_is_infinity(f32)) {
728         return float32_set_sign(float32_zero, float32_is_neg(f32));
729     } else if (float32_is_zero(f32)) {
730         float_raise(float_flag_divbyzero, fpst);
731         return float32_set_sign(float32_infinity, float32_is_neg(f32));
732     } else if (float32_abs(f32) < (1ULL << 21)) {
733         /* Abs(value) < 2.0^-128 */
734         float_raise(float_flag_overflow | float_flag_inexact, fpst);
735         if (round_to_inf(fpst, f32_sign)) {
736             return float32_set_sign(float32_infinity, f32_sign);
737         } else {
738             return float32_set_sign(float32_maxnorm, f32_sign);
739         }
740     } else if (f32_exp >= 253 && fpst->flush_to_zero) {
741         float_raise(float_flag_underflow, fpst);
742         return float32_set_sign(float32_zero, float32_is_neg(f32));
743     }
744 
745     f64_frac = call_recip_estimate(&f32_exp, 253,
746                                    ((uint64_t) f32_frac) << (52 - 23));
747 
748     /* result = sign : result_exp<7:0> : fraction<51:29> */
749     f32_val = deposit32(0, 31, 1, f32_sign);
750     f32_val = deposit32(f32_val, 23, 8, f32_exp);
751     f32_val = deposit32(f32_val, 0, 23, extract64(f64_frac, 52 - 23, 23));
752     return make_float32(f32_val);
753 }
754 
755 float64 HELPER(recpe_f64)(float64 input, void *fpstp)
756 {
757     float_status *fpst = fpstp;
758     float64 f64 = float64_squash_input_denormal(input, fpst);
759     uint64_t f64_val = float64_val(f64);
760     bool f64_sign = float64_is_neg(f64);
761     int f64_exp = extract64(f64_val, 52, 11);
762     uint64_t f64_frac = extract64(f64_val, 0, 52);
763 
764     /* Deal with any special cases */
765     if (float64_is_any_nan(f64)) {
766         float64 nan = f64;
767         if (float64_is_signaling_nan(f64, fpst)) {
768             float_raise(float_flag_invalid, fpst);
769             nan = float64_silence_nan(f64, fpst);
770         }
771         if (fpst->default_nan_mode) {
772             nan =  float64_default_nan(fpst);
773         }
774         return nan;
775     } else if (float64_is_infinity(f64)) {
776         return float64_set_sign(float64_zero, float64_is_neg(f64));
777     } else if (float64_is_zero(f64)) {
778         float_raise(float_flag_divbyzero, fpst);
779         return float64_set_sign(float64_infinity, float64_is_neg(f64));
780     } else if ((f64_val & ~(1ULL << 63)) < (1ULL << 50)) {
781         /* Abs(value) < 2.0^-1024 */
782         float_raise(float_flag_overflow | float_flag_inexact, fpst);
783         if (round_to_inf(fpst, f64_sign)) {
784             return float64_set_sign(float64_infinity, f64_sign);
785         } else {
786             return float64_set_sign(float64_maxnorm, f64_sign);
787         }
788     } else if (f64_exp >= 2045 && fpst->flush_to_zero) {
789         float_raise(float_flag_underflow, fpst);
790         return float64_set_sign(float64_zero, float64_is_neg(f64));
791     }
792 
793     f64_frac = call_recip_estimate(&f64_exp, 2045, f64_frac);
794 
795     /* result = sign : result_exp<10:0> : fraction<51:0>; */
796     f64_val = deposit64(0, 63, 1, f64_sign);
797     f64_val = deposit64(f64_val, 52, 11, f64_exp);
798     f64_val = deposit64(f64_val, 0, 52, f64_frac);
799     return make_float64(f64_val);
800 }
801 
802 /* The algorithm that must be used to calculate the estimate
803  * is specified by the ARM ARM.
804  */
805 
806 static int do_recip_sqrt_estimate(int a)
807 {
808     int b, estimate;
809 
810     assert(128 <= a && a < 512);
811     if (a < 256) {
812         a = a * 2 + 1;
813     } else {
814         a = (a >> 1) << 1;
815         a = (a + 1) * 2;
816     }
817     b = 512;
818     while (a * (b + 1) * (b + 1) < (1 << 28)) {
819         b += 1;
820     }
821     estimate = (b + 1) / 2;
822     assert(256 <= estimate && estimate < 512);
823 
824     return estimate;
825 }
826 
827 
828 static uint64_t recip_sqrt_estimate(int *exp , int exp_off, uint64_t frac)
829 {
830     int estimate;
831     uint32_t scaled;
832 
833     if (*exp == 0) {
834         while (extract64(frac, 51, 1) == 0) {
835             frac = frac << 1;
836             *exp -= 1;
837         }
838         frac = extract64(frac, 0, 51) << 1;
839     }
840 
841     if (*exp & 1) {
842         /* scaled = UInt('01':fraction<51:45>) */
843         scaled = deposit32(1 << 7, 0, 7, extract64(frac, 45, 7));
844     } else {
845         /* scaled = UInt('1':fraction<51:44>) */
846         scaled = deposit32(1 << 8, 0, 8, extract64(frac, 44, 8));
847     }
848     estimate = do_recip_sqrt_estimate(scaled);
849 
850     *exp = (exp_off - *exp) / 2;
851     return extract64(estimate, 0, 8) << 44;
852 }
853 
854 uint32_t HELPER(rsqrte_f16)(uint32_t input, void *fpstp)
855 {
856     float_status *s = fpstp;
857     float16 f16 = float16_squash_input_denormal(input, s);
858     uint16_t val = float16_val(f16);
859     bool f16_sign = float16_is_neg(f16);
860     int f16_exp = extract32(val, 10, 5);
861     uint16_t f16_frac = extract32(val, 0, 10);
862     uint64_t f64_frac;
863 
864     if (float16_is_any_nan(f16)) {
865         float16 nan = f16;
866         if (float16_is_signaling_nan(f16, s)) {
867             float_raise(float_flag_invalid, s);
868             nan = float16_silence_nan(f16, s);
869         }
870         if (s->default_nan_mode) {
871             nan =  float16_default_nan(s);
872         }
873         return nan;
874     } else if (float16_is_zero(f16)) {
875         float_raise(float_flag_divbyzero, s);
876         return float16_set_sign(float16_infinity, f16_sign);
877     } else if (f16_sign) {
878         float_raise(float_flag_invalid, s);
879         return float16_default_nan(s);
880     } else if (float16_is_infinity(f16)) {
881         return float16_zero;
882     }
883 
884     /* Scale and normalize to a double-precision value between 0.25 and 1.0,
885      * preserving the parity of the exponent.  */
886 
887     f64_frac = ((uint64_t) f16_frac) << (52 - 10);
888 
889     f64_frac = recip_sqrt_estimate(&f16_exp, 44, f64_frac);
890 
891     /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(2) */
892     val = deposit32(0, 15, 1, f16_sign);
893     val = deposit32(val, 10, 5, f16_exp);
894     val = deposit32(val, 2, 8, extract64(f64_frac, 52 - 8, 8));
895     return make_float16(val);
896 }
897 
898 float32 HELPER(rsqrte_f32)(float32 input, void *fpstp)
899 {
900     float_status *s = fpstp;
901     float32 f32 = float32_squash_input_denormal(input, s);
902     uint32_t val = float32_val(f32);
903     uint32_t f32_sign = float32_is_neg(f32);
904     int f32_exp = extract32(val, 23, 8);
905     uint32_t f32_frac = extract32(val, 0, 23);
906     uint64_t f64_frac;
907 
908     if (float32_is_any_nan(f32)) {
909         float32 nan = f32;
910         if (float32_is_signaling_nan(f32, s)) {
911             float_raise(float_flag_invalid, s);
912             nan = float32_silence_nan(f32, s);
913         }
914         if (s->default_nan_mode) {
915             nan =  float32_default_nan(s);
916         }
917         return nan;
918     } else if (float32_is_zero(f32)) {
919         float_raise(float_flag_divbyzero, s);
920         return float32_set_sign(float32_infinity, float32_is_neg(f32));
921     } else if (float32_is_neg(f32)) {
922         float_raise(float_flag_invalid, s);
923         return float32_default_nan(s);
924     } else if (float32_is_infinity(f32)) {
925         return float32_zero;
926     }
927 
928     /* Scale and normalize to a double-precision value between 0.25 and 1.0,
929      * preserving the parity of the exponent.  */
930 
931     f64_frac = ((uint64_t) f32_frac) << 29;
932 
933     f64_frac = recip_sqrt_estimate(&f32_exp, 380, f64_frac);
934 
935     /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(15) */
936     val = deposit32(0, 31, 1, f32_sign);
937     val = deposit32(val, 23, 8, f32_exp);
938     val = deposit32(val, 15, 8, extract64(f64_frac, 52 - 8, 8));
939     return make_float32(val);
940 }
941 
942 float64 HELPER(rsqrte_f64)(float64 input, void *fpstp)
943 {
944     float_status *s = fpstp;
945     float64 f64 = float64_squash_input_denormal(input, s);
946     uint64_t val = float64_val(f64);
947     bool f64_sign = float64_is_neg(f64);
948     int f64_exp = extract64(val, 52, 11);
949     uint64_t f64_frac = extract64(val, 0, 52);
950 
951     if (float64_is_any_nan(f64)) {
952         float64 nan = f64;
953         if (float64_is_signaling_nan(f64, s)) {
954             float_raise(float_flag_invalid, s);
955             nan = float64_silence_nan(f64, s);
956         }
957         if (s->default_nan_mode) {
958             nan =  float64_default_nan(s);
959         }
960         return nan;
961     } else if (float64_is_zero(f64)) {
962         float_raise(float_flag_divbyzero, s);
963         return float64_set_sign(float64_infinity, float64_is_neg(f64));
964     } else if (float64_is_neg(f64)) {
965         float_raise(float_flag_invalid, s);
966         return float64_default_nan(s);
967     } else if (float64_is_infinity(f64)) {
968         return float64_zero;
969     }
970 
971     f64_frac = recip_sqrt_estimate(&f64_exp, 3068, f64_frac);
972 
973     /* result = sign : result_exp<4:0> : estimate<7:0> : Zeros(44) */
974     val = deposit64(0, 61, 1, f64_sign);
975     val = deposit64(val, 52, 11, f64_exp);
976     val = deposit64(val, 44, 8, extract64(f64_frac, 52 - 8, 8));
977     return make_float64(val);
978 }
979 
980 uint32_t HELPER(recpe_u32)(uint32_t a)
981 {
982     int input, estimate;
983 
984     if ((a & 0x80000000) == 0) {
985         return 0xffffffff;
986     }
987 
988     input = extract32(a, 23, 9);
989     estimate = recip_estimate(input);
990 
991     return deposit32(0, (32 - 9), 9, estimate);
992 }
993 
994 uint32_t HELPER(rsqrte_u32)(uint32_t a)
995 {
996     int estimate;
997 
998     if ((a & 0xc0000000) == 0) {
999         return 0xffffffff;
1000     }
1001 
1002     estimate = do_recip_sqrt_estimate(extract32(a, 23, 9));
1003 
1004     return deposit32(0, 23, 9, estimate);
1005 }
1006 
1007 /* VFPv4 fused multiply-accumulate */
1008 dh_ctype_f16 VFP_HELPER(muladd, h)(dh_ctype_f16 a, dh_ctype_f16 b,
1009                                    dh_ctype_f16 c, void *fpstp)
1010 {
1011     float_status *fpst = fpstp;
1012     return float16_muladd(a, b, c, 0, fpst);
1013 }
1014 
1015 float32 VFP_HELPER(muladd, s)(float32 a, float32 b, float32 c, void *fpstp)
1016 {
1017     float_status *fpst = fpstp;
1018     return float32_muladd(a, b, c, 0, fpst);
1019 }
1020 
1021 float64 VFP_HELPER(muladd, d)(float64 a, float64 b, float64 c, void *fpstp)
1022 {
1023     float_status *fpst = fpstp;
1024     return float64_muladd(a, b, c, 0, fpst);
1025 }
1026 
1027 /* ARMv8 round to integral */
1028 dh_ctype_f16 HELPER(rinth_exact)(dh_ctype_f16 x, void *fp_status)
1029 {
1030     return float16_round_to_int(x, fp_status);
1031 }
1032 
1033 float32 HELPER(rints_exact)(float32 x, void *fp_status)
1034 {
1035     return float32_round_to_int(x, fp_status);
1036 }
1037 
1038 float64 HELPER(rintd_exact)(float64 x, void *fp_status)
1039 {
1040     return float64_round_to_int(x, fp_status);
1041 }
1042 
1043 dh_ctype_f16 HELPER(rinth)(dh_ctype_f16 x, void *fp_status)
1044 {
1045     int old_flags = get_float_exception_flags(fp_status), new_flags;
1046     float16 ret;
1047 
1048     ret = float16_round_to_int(x, fp_status);
1049 
1050     /* Suppress any inexact exceptions the conversion produced */
1051     if (!(old_flags & float_flag_inexact)) {
1052         new_flags = get_float_exception_flags(fp_status);
1053         set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status);
1054     }
1055 
1056     return ret;
1057 }
1058 
1059 float32 HELPER(rints)(float32 x, void *fp_status)
1060 {
1061     int old_flags = get_float_exception_flags(fp_status), new_flags;
1062     float32 ret;
1063 
1064     ret = float32_round_to_int(x, fp_status);
1065 
1066     /* Suppress any inexact exceptions the conversion produced */
1067     if (!(old_flags & float_flag_inexact)) {
1068         new_flags = get_float_exception_flags(fp_status);
1069         set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status);
1070     }
1071 
1072     return ret;
1073 }
1074 
1075 float64 HELPER(rintd)(float64 x, void *fp_status)
1076 {
1077     int old_flags = get_float_exception_flags(fp_status), new_flags;
1078     float64 ret;
1079 
1080     ret = float64_round_to_int(x, fp_status);
1081 
1082     new_flags = get_float_exception_flags(fp_status);
1083 
1084     /* Suppress any inexact exceptions the conversion produced */
1085     if (!(old_flags & float_flag_inexact)) {
1086         new_flags = get_float_exception_flags(fp_status);
1087         set_float_exception_flags(new_flags & ~float_flag_inexact, fp_status);
1088     }
1089 
1090     return ret;
1091 }
1092 
1093 /* Convert ARM rounding mode to softfloat */
1094 int arm_rmode_to_sf(int rmode)
1095 {
1096     switch (rmode) {
1097     case FPROUNDING_TIEAWAY:
1098         rmode = float_round_ties_away;
1099         break;
1100     case FPROUNDING_ODD:
1101         /* FIXME: add support for TIEAWAY and ODD */
1102         qemu_log_mask(LOG_UNIMP, "arm: unimplemented rounding mode: %d\n",
1103                       rmode);
1104         /* fall through for now */
1105     case FPROUNDING_TIEEVEN:
1106     default:
1107         rmode = float_round_nearest_even;
1108         break;
1109     case FPROUNDING_POSINF:
1110         rmode = float_round_up;
1111         break;
1112     case FPROUNDING_NEGINF:
1113         rmode = float_round_down;
1114         break;
1115     case FPROUNDING_ZERO:
1116         rmode = float_round_to_zero;
1117         break;
1118     }
1119     return rmode;
1120 }
1121 
1122 /*
1123  * Implement float64 to int32_t conversion without saturation;
1124  * the result is supplied modulo 2^32.
1125  */
1126 uint64_t HELPER(fjcvtzs)(float64 value, void *vstatus)
1127 {
1128     float_status *status = vstatus;
1129     uint32_t exp, sign;
1130     uint64_t frac;
1131     uint32_t inexact = 1; /* !Z */
1132 
1133     sign = extract64(value, 63, 1);
1134     exp = extract64(value, 52, 11);
1135     frac = extract64(value, 0, 52);
1136 
1137     if (exp == 0) {
1138         /* While not inexact for IEEE FP, -0.0 is inexact for JavaScript.  */
1139         inexact = sign;
1140         if (frac != 0) {
1141             if (status->flush_inputs_to_zero) {
1142                 float_raise(float_flag_input_denormal, status);
1143             } else {
1144                 float_raise(float_flag_inexact, status);
1145                 inexact = 1;
1146             }
1147         }
1148         frac = 0;
1149     } else if (exp == 0x7ff) {
1150         /* This operation raises Invalid for both NaN and overflow (Inf).  */
1151         float_raise(float_flag_invalid, status);
1152         frac = 0;
1153     } else {
1154         int true_exp = exp - 1023;
1155         int shift = true_exp - 52;
1156 
1157         /* Restore implicit bit.  */
1158         frac |= 1ull << 52;
1159 
1160         /* Shift the fraction into place.  */
1161         if (shift >= 0) {
1162             /* The number is so large we must shift the fraction left.  */
1163             if (shift >= 64) {
1164                 /* The fraction is shifted out entirely.  */
1165                 frac = 0;
1166             } else {
1167                 frac <<= shift;
1168             }
1169         } else if (shift > -64) {
1170             /* Normal case -- shift right and notice if bits shift out.  */
1171             inexact = (frac << (64 + shift)) != 0;
1172             frac >>= -shift;
1173         } else {
1174             /* The fraction is shifted out entirely.  */
1175             frac = 0;
1176         }
1177 
1178         /* Notice overflow or inexact exceptions.  */
1179         if (true_exp > 31 || frac > (sign ? 0x80000000ull : 0x7fffffff)) {
1180             /* Overflow, for which this operation raises invalid.  */
1181             float_raise(float_flag_invalid, status);
1182             inexact = 1;
1183         } else if (inexact) {
1184             float_raise(float_flag_inexact, status);
1185         }
1186 
1187         /* Honor the sign.  */
1188         if (sign) {
1189             frac = -frac;
1190         }
1191     }
1192 
1193     /* Pack the result and the env->ZF representation of Z together.  */
1194     return deposit64(frac, 32, 32, inexact);
1195 }
1196 
1197 uint32_t HELPER(vjcvt)(float64 value, CPUARMState *env)
1198 {
1199     uint64_t pair = HELPER(fjcvtzs)(value, &env->vfp.fp_status);
1200     uint32_t result = pair;
1201     uint32_t z = (pair >> 32) == 0;
1202 
1203     /* Store Z, clear NCV, in FPSCR.NZCV.  */
1204     env->vfp.xregs[ARM_VFP_FPSCR]
1205         = (env->vfp.xregs[ARM_VFP_FPSCR] & ~CPSR_NZCV) | (z * CPSR_Z);
1206 
1207     return result;
1208 }
1209 
1210 /* Round a float32 to an integer that fits in int32_t or int64_t.  */
1211 static float32 frint_s(float32 f, float_status *fpst, int intsize)
1212 {
1213     int old_flags = get_float_exception_flags(fpst);
1214     uint32_t exp = extract32(f, 23, 8);
1215 
1216     if (unlikely(exp == 0xff)) {
1217         /* NaN or Inf.  */
1218         goto overflow;
1219     }
1220 
1221     /* Round and re-extract the exponent.  */
1222     f = float32_round_to_int(f, fpst);
1223     exp = extract32(f, 23, 8);
1224 
1225     /* Validate the range of the result.  */
1226     if (exp < 126 + intsize) {
1227         /* abs(F) <= INT{N}_MAX */
1228         return f;
1229     }
1230     if (exp == 126 + intsize) {
1231         uint32_t sign = extract32(f, 31, 1);
1232         uint32_t frac = extract32(f, 0, 23);
1233         if (sign && frac == 0) {
1234             /* F == INT{N}_MIN */
1235             return f;
1236         }
1237     }
1238 
1239  overflow:
1240     /*
1241      * Raise Invalid and return INT{N}_MIN as a float.  Revert any
1242      * inexact exception float32_round_to_int may have raised.
1243      */
1244     set_float_exception_flags(old_flags | float_flag_invalid, fpst);
1245     return (0x100u + 126u + intsize) << 23;
1246 }
1247 
1248 float32 HELPER(frint32_s)(float32 f, void *fpst)
1249 {
1250     return frint_s(f, fpst, 32);
1251 }
1252 
1253 float32 HELPER(frint64_s)(float32 f, void *fpst)
1254 {
1255     return frint_s(f, fpst, 64);
1256 }
1257 
1258 /* Round a float64 to an integer that fits in int32_t or int64_t.  */
1259 static float64 frint_d(float64 f, float_status *fpst, int intsize)
1260 {
1261     int old_flags = get_float_exception_flags(fpst);
1262     uint32_t exp = extract64(f, 52, 11);
1263 
1264     if (unlikely(exp == 0x7ff)) {
1265         /* NaN or Inf.  */
1266         goto overflow;
1267     }
1268 
1269     /* Round and re-extract the exponent.  */
1270     f = float64_round_to_int(f, fpst);
1271     exp = extract64(f, 52, 11);
1272 
1273     /* Validate the range of the result.  */
1274     if (exp < 1022 + intsize) {
1275         /* abs(F) <= INT{N}_MAX */
1276         return f;
1277     }
1278     if (exp == 1022 + intsize) {
1279         uint64_t sign = extract64(f, 63, 1);
1280         uint64_t frac = extract64(f, 0, 52);
1281         if (sign && frac == 0) {
1282             /* F == INT{N}_MIN */
1283             return f;
1284         }
1285     }
1286 
1287  overflow:
1288     /*
1289      * Raise Invalid and return INT{N}_MIN as a float.  Revert any
1290      * inexact exception float64_round_to_int may have raised.
1291      */
1292     set_float_exception_flags(old_flags | float_flag_invalid, fpst);
1293     return (uint64_t)(0x800 + 1022 + intsize) << 52;
1294 }
1295 
1296 float64 HELPER(frint32_d)(float64 f, void *fpst)
1297 {
1298     return frint_d(f, fpst, 32);
1299 }
1300 
1301 float64 HELPER(frint64_d)(float64 f, void *fpst)
1302 {
1303     return frint_d(f, fpst, 64);
1304 }
1305 
1306 void HELPER(check_hcr_el2_trap)(CPUARMState *env, uint32_t rt, uint32_t reg)
1307 {
1308     uint32_t syndrome;
1309 
1310     switch (reg) {
1311     case ARM_VFP_MVFR0:
1312     case ARM_VFP_MVFR1:
1313     case ARM_VFP_MVFR2:
1314         if (!(arm_hcr_el2_eff(env) & HCR_TID3)) {
1315             return;
1316         }
1317         break;
1318     case ARM_VFP_FPSID:
1319         if (!(arm_hcr_el2_eff(env) & HCR_TID0)) {
1320             return;
1321         }
1322         break;
1323     default:
1324         g_assert_not_reached();
1325     }
1326 
1327     syndrome = ((EC_FPIDTRAP << ARM_EL_EC_SHIFT)
1328                 | ARM_EL_IL
1329                 | (1 << 24) | (0xe << 20) | (7 << 14)
1330                 | (reg << 10) | (rt << 5) | 1);
1331 
1332     raise_exception(env, EXCP_HYP_TRAP, syndrome, 2);
1333 }
1334 
1335 #endif
1336