exec: fix madvise of NULL pointer
[qemu.git] / target-arm / helper-a64.c
blob81066ca936e85e9cd87340edb740151ba666bf4d
1 /*
2 * AArch64 specific helpers
4 * Copyright (c) 2013 Alexander Graf <agraf@suse.de>
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 of the License, or (at your option) any later version.
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.
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/>.
20 #include "cpu.h"
21 #include "exec/gdbstub.h"
22 #include "exec/helper-proto.h"
23 #include "qemu/host-utils.h"
24 #include "sysemu/sysemu.h"
25 #include "qemu/bitops.h"
26 #include "internals.h"
27 #include "qemu/crc32c.h"
28 #include <zlib.h> /* For crc32 */
30 /* C2.4.7 Multiply and divide */
31 /* special cases for 0 and LLONG_MIN are mandated by the standard */
32 uint64_t HELPER(udiv64)(uint64_t num, uint64_t den)
34 if (den == 0) {
35 return 0;
37 return num / den;
40 int64_t HELPER(sdiv64)(int64_t num, int64_t den)
42 if (den == 0) {
43 return 0;
45 if (num == LLONG_MIN && den == -1) {
46 return LLONG_MIN;
48 return num / den;
51 uint64_t HELPER(clz64)(uint64_t x)
53 return clz64(x);
56 uint64_t HELPER(cls64)(uint64_t x)
58 return clrsb64(x);
61 uint32_t HELPER(cls32)(uint32_t x)
63 return clrsb32(x);
66 uint32_t HELPER(clz32)(uint32_t x)
68 return clz32(x);
71 uint64_t HELPER(rbit64)(uint64_t x)
73 /* assign the correct byte position */
74 x = bswap64(x);
76 /* assign the correct nibble position */
77 x = ((x & 0xf0f0f0f0f0f0f0f0ULL) >> 4)
78 | ((x & 0x0f0f0f0f0f0f0f0fULL) << 4);
80 /* assign the correct bit position */
81 x = ((x & 0x8888888888888888ULL) >> 3)
82 | ((x & 0x4444444444444444ULL) >> 1)
83 | ((x & 0x2222222222222222ULL) << 1)
84 | ((x & 0x1111111111111111ULL) << 3);
86 return x;
89 /* Convert a softfloat float_relation_ (as returned by
90 * the float*_compare functions) to the correct ARM
91 * NZCV flag state.
93 static inline uint32_t float_rel_to_flags(int res)
95 uint64_t flags;
96 switch (res) {
97 case float_relation_equal:
98 flags = PSTATE_Z | PSTATE_C;
99 break;
100 case float_relation_less:
101 flags = PSTATE_N;
102 break;
103 case float_relation_greater:
104 flags = PSTATE_C;
105 break;
106 case float_relation_unordered:
107 default:
108 flags = PSTATE_C | PSTATE_V;
109 break;
111 return flags;
114 uint64_t HELPER(vfp_cmps_a64)(float32 x, float32 y, void *fp_status)
116 return float_rel_to_flags(float32_compare_quiet(x, y, fp_status));
119 uint64_t HELPER(vfp_cmpes_a64)(float32 x, float32 y, void *fp_status)
121 return float_rel_to_flags(float32_compare(x, y, fp_status));
124 uint64_t HELPER(vfp_cmpd_a64)(float64 x, float64 y, void *fp_status)
126 return float_rel_to_flags(float64_compare_quiet(x, y, fp_status));
129 uint64_t HELPER(vfp_cmped_a64)(float64 x, float64 y, void *fp_status)
131 return float_rel_to_flags(float64_compare(x, y, fp_status));
134 float32 HELPER(vfp_mulxs)(float32 a, float32 b, void *fpstp)
136 float_status *fpst = fpstp;
138 if ((float32_is_zero(a) && float32_is_infinity(b)) ||
139 (float32_is_infinity(a) && float32_is_zero(b))) {
140 /* 2.0 with the sign bit set to sign(A) XOR sign(B) */
141 return make_float32((1U << 30) |
142 ((float32_val(a) ^ float32_val(b)) & (1U << 31)));
144 return float32_mul(a, b, fpst);
147 float64 HELPER(vfp_mulxd)(float64 a, float64 b, void *fpstp)
149 float_status *fpst = fpstp;
151 if ((float64_is_zero(a) && float64_is_infinity(b)) ||
152 (float64_is_infinity(a) && float64_is_zero(b))) {
153 /* 2.0 with the sign bit set to sign(A) XOR sign(B) */
154 return make_float64((1ULL << 62) |
155 ((float64_val(a) ^ float64_val(b)) & (1ULL << 63)));
157 return float64_mul(a, b, fpst);
160 uint64_t HELPER(simd_tbl)(CPUARMState *env, uint64_t result, uint64_t indices,
161 uint32_t rn, uint32_t numregs)
163 /* Helper function for SIMD TBL and TBX. We have to do the table
164 * lookup part for the 64 bits worth of indices we're passed in.
165 * result is the initial results vector (either zeroes for TBL
166 * or some guest values for TBX), rn the register number where
167 * the table starts, and numregs the number of registers in the table.
168 * We return the results of the lookups.
170 int shift;
172 for (shift = 0; shift < 64; shift += 8) {
173 int index = extract64(indices, shift, 8);
174 if (index < 16 * numregs) {
175 /* Convert index (a byte offset into the virtual table
176 * which is a series of 128-bit vectors concatenated)
177 * into the correct vfp.regs[] element plus a bit offset
178 * into that element, bearing in mind that the table
179 * can wrap around from V31 to V0.
181 int elt = (rn * 2 + (index >> 3)) % 64;
182 int bitidx = (index & 7) * 8;
183 uint64_t val = extract64(env->vfp.regs[elt], bitidx, 8);
185 result = deposit64(result, shift, 8, val);
188 return result;
191 /* 64bit/double versions of the neon float compare functions */
192 uint64_t HELPER(neon_ceq_f64)(float64 a, float64 b, void *fpstp)
194 float_status *fpst = fpstp;
195 return -float64_eq_quiet(a, b, fpst);
198 uint64_t HELPER(neon_cge_f64)(float64 a, float64 b, void *fpstp)
200 float_status *fpst = fpstp;
201 return -float64_le(b, a, fpst);
204 uint64_t HELPER(neon_cgt_f64)(float64 a, float64 b, void *fpstp)
206 float_status *fpst = fpstp;
207 return -float64_lt(b, a, fpst);
210 /* Reciprocal step and sqrt step. Note that unlike the A32/T32
211 * versions, these do a fully fused multiply-add or
212 * multiply-add-and-halve.
214 #define float32_two make_float32(0x40000000)
215 #define float32_three make_float32(0x40400000)
216 #define float32_one_point_five make_float32(0x3fc00000)
218 #define float64_two make_float64(0x4000000000000000ULL)
219 #define float64_three make_float64(0x4008000000000000ULL)
220 #define float64_one_point_five make_float64(0x3FF8000000000000ULL)
222 float32 HELPER(recpsf_f32)(float32 a, float32 b, void *fpstp)
224 float_status *fpst = fpstp;
226 a = float32_chs(a);
227 if ((float32_is_infinity(a) && float32_is_zero(b)) ||
228 (float32_is_infinity(b) && float32_is_zero(a))) {
229 return float32_two;
231 return float32_muladd(a, b, float32_two, 0, fpst);
234 float64 HELPER(recpsf_f64)(float64 a, float64 b, void *fpstp)
236 float_status *fpst = fpstp;
238 a = float64_chs(a);
239 if ((float64_is_infinity(a) && float64_is_zero(b)) ||
240 (float64_is_infinity(b) && float64_is_zero(a))) {
241 return float64_two;
243 return float64_muladd(a, b, float64_two, 0, fpst);
246 float32 HELPER(rsqrtsf_f32)(float32 a, float32 b, void *fpstp)
248 float_status *fpst = fpstp;
250 a = float32_chs(a);
251 if ((float32_is_infinity(a) && float32_is_zero(b)) ||
252 (float32_is_infinity(b) && float32_is_zero(a))) {
253 return float32_one_point_five;
255 return float32_muladd(a, b, float32_three, float_muladd_halve_result, fpst);
258 float64 HELPER(rsqrtsf_f64)(float64 a, float64 b, void *fpstp)
260 float_status *fpst = fpstp;
262 a = float64_chs(a);
263 if ((float64_is_infinity(a) && float64_is_zero(b)) ||
264 (float64_is_infinity(b) && float64_is_zero(a))) {
265 return float64_one_point_five;
267 return float64_muladd(a, b, float64_three, float_muladd_halve_result, fpst);
270 /* Pairwise long add: add pairs of adjacent elements into
271 * double-width elements in the result (eg _s8 is an 8x8->16 op)
273 uint64_t HELPER(neon_addlp_s8)(uint64_t a)
275 uint64_t nsignmask = 0x0080008000800080ULL;
276 uint64_t wsignmask = 0x8000800080008000ULL;
277 uint64_t elementmask = 0x00ff00ff00ff00ffULL;
278 uint64_t tmp1, tmp2;
279 uint64_t res, signres;
281 /* Extract odd elements, sign extend each to a 16 bit field */
282 tmp1 = a & elementmask;
283 tmp1 ^= nsignmask;
284 tmp1 |= wsignmask;
285 tmp1 = (tmp1 - nsignmask) ^ wsignmask;
286 /* Ditto for the even elements */
287 tmp2 = (a >> 8) & elementmask;
288 tmp2 ^= nsignmask;
289 tmp2 |= wsignmask;
290 tmp2 = (tmp2 - nsignmask) ^ wsignmask;
292 /* calculate the result by summing bits 0..14, 16..22, etc,
293 * and then adjusting the sign bits 15, 23, etc manually.
294 * This ensures the addition can't overflow the 16 bit field.
296 signres = (tmp1 ^ tmp2) & wsignmask;
297 res = (tmp1 & ~wsignmask) + (tmp2 & ~wsignmask);
298 res ^= signres;
300 return res;
303 uint64_t HELPER(neon_addlp_u8)(uint64_t a)
305 uint64_t tmp;
307 tmp = a & 0x00ff00ff00ff00ffULL;
308 tmp += (a >> 8) & 0x00ff00ff00ff00ffULL;
309 return tmp;
312 uint64_t HELPER(neon_addlp_s16)(uint64_t a)
314 int32_t reslo, reshi;
316 reslo = (int32_t)(int16_t)a + (int32_t)(int16_t)(a >> 16);
317 reshi = (int32_t)(int16_t)(a >> 32) + (int32_t)(int16_t)(a >> 48);
319 return (uint32_t)reslo | (((uint64_t)reshi) << 32);
322 uint64_t HELPER(neon_addlp_u16)(uint64_t a)
324 uint64_t tmp;
326 tmp = a & 0x0000ffff0000ffffULL;
327 tmp += (a >> 16) & 0x0000ffff0000ffffULL;
328 return tmp;
331 /* Floating-point reciprocal exponent - see FPRecpX in ARM ARM */
332 float32 HELPER(frecpx_f32)(float32 a, void *fpstp)
334 float_status *fpst = fpstp;
335 uint32_t val32, sbit;
336 int32_t exp;
338 if (float32_is_any_nan(a)) {
339 float32 nan = a;
340 if (float32_is_signaling_nan(a)) {
341 float_raise(float_flag_invalid, fpst);
342 nan = float32_maybe_silence_nan(a);
344 if (fpst->default_nan_mode) {
345 nan = float32_default_nan;
347 return nan;
350 val32 = float32_val(a);
351 sbit = 0x80000000ULL & val32;
352 exp = extract32(val32, 23, 8);
354 if (exp == 0) {
355 return make_float32(sbit | (0xfe << 23));
356 } else {
357 return make_float32(sbit | (~exp & 0xff) << 23);
361 float64 HELPER(frecpx_f64)(float64 a, void *fpstp)
363 float_status *fpst = fpstp;
364 uint64_t val64, sbit;
365 int64_t exp;
367 if (float64_is_any_nan(a)) {
368 float64 nan = a;
369 if (float64_is_signaling_nan(a)) {
370 float_raise(float_flag_invalid, fpst);
371 nan = float64_maybe_silence_nan(a);
373 if (fpst->default_nan_mode) {
374 nan = float64_default_nan;
376 return nan;
379 val64 = float64_val(a);
380 sbit = 0x8000000000000000ULL & val64;
381 exp = extract64(float64_val(a), 52, 11);
383 if (exp == 0) {
384 return make_float64(sbit | (0x7feULL << 52));
385 } else {
386 return make_float64(sbit | (~exp & 0x7ffULL) << 52);
390 float32 HELPER(fcvtx_f64_to_f32)(float64 a, CPUARMState *env)
392 /* Von Neumann rounding is implemented by using round-to-zero
393 * and then setting the LSB of the result if Inexact was raised.
395 float32 r;
396 float_status *fpst = &env->vfp.fp_status;
397 float_status tstat = *fpst;
398 int exflags;
400 set_float_rounding_mode(float_round_to_zero, &tstat);
401 set_float_exception_flags(0, &tstat);
402 r = float64_to_float32(a, &tstat);
403 r = float32_maybe_silence_nan(r);
404 exflags = get_float_exception_flags(&tstat);
405 if (exflags & float_flag_inexact) {
406 r = make_float32(float32_val(r) | 1);
408 exflags |= get_float_exception_flags(fpst);
409 set_float_exception_flags(exflags, fpst);
410 return r;
413 /* 64-bit versions of the CRC helpers. Note that although the operation
414 * (and the prototypes of crc32c() and crc32() mean that only the bottom
415 * 32 bits of the accumulator and result are used, we pass and return
416 * uint64_t for convenience of the generated code. Unlike the 32-bit
417 * instruction set versions, val may genuinely have 64 bits of data in it.
418 * The upper bytes of val (above the number specified by 'bytes') must have
419 * been zeroed out by the caller.
421 uint64_t HELPER(crc32_64)(uint64_t acc, uint64_t val, uint32_t bytes)
423 uint8_t buf[8];
425 stq_le_p(buf, val);
427 /* zlib crc32 converts the accumulator and output to one's complement. */
428 return crc32(acc ^ 0xffffffff, buf, bytes) ^ 0xffffffff;
431 uint64_t HELPER(crc32c_64)(uint64_t acc, uint64_t val, uint32_t bytes)
433 uint8_t buf[8];
435 stq_le_p(buf, val);
437 /* Linux crc32c converts the output to one's complement. */
438 return crc32c(acc, buf, bytes) ^ 0xffffffff;
441 #if !defined(CONFIG_USER_ONLY)
443 /* Handle a CPU exception. */
444 void aarch64_cpu_do_interrupt(CPUState *cs)
446 ARMCPU *cpu = ARM_CPU(cs);
447 CPUARMState *env = &cpu->env;
448 unsigned int new_el = arm_excp_target_el(cs, cs->exception_index);
449 target_ulong addr = env->cp15.vbar_el[new_el];
450 unsigned int new_mode = aarch64_pstate_mode(new_el, true);
451 int i;
453 if (arm_current_el(env) < new_el) {
454 if (env->aarch64) {
455 addr += 0x400;
456 } else {
457 addr += 0x600;
459 } else if (pstate_read(env) & PSTATE_SP) {
460 addr += 0x200;
463 arm_log_exception(cs->exception_index);
464 qemu_log_mask(CPU_LOG_INT, "...from EL%d\n", arm_current_el(env));
465 if (qemu_loglevel_mask(CPU_LOG_INT)
466 && !excp_is_internal(cs->exception_index)) {
467 qemu_log_mask(CPU_LOG_INT, "...with ESR 0x%" PRIx32 "\n",
468 env->exception.syndrome);
471 if (arm_is_psci_call(cpu, cs->exception_index)) {
472 arm_handle_psci_call(cpu);
473 qemu_log_mask(CPU_LOG_INT, "...handled as PSCI call\n");
474 return;
477 switch (cs->exception_index) {
478 case EXCP_PREFETCH_ABORT:
479 case EXCP_DATA_ABORT:
480 env->cp15.far_el[new_el] = env->exception.vaddress;
481 qemu_log_mask(CPU_LOG_INT, "...with FAR 0x%" PRIx64 "\n",
482 env->cp15.far_el[new_el]);
483 /* fall through */
484 case EXCP_BKPT:
485 case EXCP_UDEF:
486 case EXCP_SWI:
487 case EXCP_HVC:
488 case EXCP_HYP_TRAP:
489 case EXCP_SMC:
490 env->cp15.esr_el[new_el] = env->exception.syndrome;
491 break;
492 case EXCP_IRQ:
493 case EXCP_VIRQ:
494 addr += 0x80;
495 break;
496 case EXCP_FIQ:
497 case EXCP_VFIQ:
498 addr += 0x100;
499 break;
500 default:
501 cpu_abort(cs, "Unhandled exception 0x%x\n", cs->exception_index);
504 if (is_a64(env)) {
505 env->banked_spsr[aarch64_banked_spsr_index(new_el)] = pstate_read(env);
506 aarch64_save_sp(env, arm_current_el(env));
507 env->elr_el[new_el] = env->pc;
508 } else {
509 env->banked_spsr[0] = cpsr_read(env);
510 if (!env->thumb) {
511 env->cp15.esr_el[new_el] |= 1 << 25;
513 env->elr_el[new_el] = env->regs[15];
515 for (i = 0; i < 15; i++) {
516 env->xregs[i] = env->regs[i];
519 env->condexec_bits = 0;
522 pstate_write(env, PSTATE_DAIF | new_mode);
523 env->aarch64 = 1;
524 aarch64_restore_sp(env, new_el);
526 env->pc = addr;
527 cs->interrupt_request |= CPU_INTERRUPT_EXITTB;
529 #endif