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1/*
2 * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * @OSF_COPYRIGHT@
30 */
31/*
32 * Mach Operating System
33 * Copyright (c) 1991,1990,1989 Carnegie Mellon University
34 * All Rights Reserved.
35 *
36 * Permission to use, copy, modify and distribute this software and its
37 * documentation is hereby granted, provided that both the copyright
38 * notice and this permission notice appear in all copies of the
39 * software, derivative works or modified versions, and any portions
40 * thereof, and that both notices appear in supporting documentation.
41 *
42 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45 *
46 * Carnegie Mellon requests users of this software to return to
47 *
48 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
49 * School of Computer Science
50 * Carnegie Mellon University
51 * Pittsburgh PA 15213-3890
52 *
53 * any improvements or extensions that they make and grant Carnegie Mellon
54 * the rights to redistribute these changes.
55 */
56/*
57 */
58#include <mach_assert.h>
59
60#include <string.h>
61#include <mach/boolean.h>
62#include <mach/i386/vm_types.h>
63#include <mach/i386/vm_param.h>
64#include <kern/kern_types.h>
65#include <kern/misc_protos.h>
66#include <sys/errno.h>
67#include <i386/param.h>
68#include <i386/misc_protos.h>
69#include <i386/cpu_data.h>
70#include <i386/machine_routines.h>
71#include <i386/cpuid.h>
72#include <i386/vmx.h>
73#include <vm/pmap.h>
74#include <vm/vm_map.h>
75#include <vm/vm_kern.h>
76#include <vm/vm_fault.h>
77
78#include <libkern/OSAtomic.h>
79#include <sys/kdebug.h>
80
81#if 0
82
83#undef KERNEL_DEBUG
84#define KERNEL_DEBUG KERNEL_DEBUG_CONSTANT
85#define KDEBUG 1
86
87#endif
88
89/* XXX - should be gone from here */
90extern void invalidate_icache64(addr64_t addr, unsigned cnt, int phys);
91extern void flush_dcache64(addr64_t addr, unsigned count, int phys);
92extern boolean_t phys_page_exists(ppnum_t);
93extern void bcopy_no_overwrite(const char *from, char *to,vm_size_t bytes);
94extern void pmap_set_reference(ppnum_t pn);
95extern void mapping_set_mod(ppnum_t pa);
96extern void mapping_set_ref(ppnum_t pn);
97
98extern void ovbcopy(const char *from,
99 char *to,
100 vm_size_t nbytes);
101void machine_callstack(natural_t *buf, vm_size_t callstack_max);
102
103
104#define value_64bit(value) ((value) & 0xFFFFFFFF00000000LL)
105#define low32(x) ((unsigned int)((x) & 0x00000000FFFFFFFFLL))
106
107#define JOE_DEBUG 0
108
109void
110bzero_phys_nc(
111 addr64_t src64,
112 uint32_t bytes)
113{
114 bzero_phys(src64,bytes);
115}
116
117void
118bzero_phys(
119 addr64_t src64,
120 uint32_t bytes)
121{
122 mapwindow_t *map;
123
124 mp_disable_preemption();
125
126 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | ((pmap_paddr_t)src64 & PG_FRAME) | INTEL_PTE_REF | INTEL_PTE_MOD));
127
128 bzero((void *)((uintptr_t)map->prv_CADDR | ((uint32_t)src64 & INTEL_OFFMASK)), bytes);
129
130 pmap_put_mapwindow(map);
131
132 mp_enable_preemption();
133}
134
135
136/*
137 * bcopy_phys - like bcopy but copies from/to physical addresses.
138 */
139
140void
141bcopy_phys(
142 addr64_t src64,
143 addr64_t dst64,
144 vm_size_t bytes)
145{
146 mapwindow_t *src_map, *dst_map;
147
148 /* ensure we stay within a page */
149 if ( ((((uint32_t)src64 & (NBPG-1)) + bytes) > NBPG) || ((((uint32_t)dst64 & (NBPG-1)) + bytes) > NBPG) ) {
150 panic("bcopy_phys alignment");
151 }
152 mp_disable_preemption();
153
154 src_map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | ((pmap_paddr_t)src64 & PG_FRAME) | INTEL_PTE_REF));
155 dst_map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | ((pmap_paddr_t)dst64 & PG_FRAME) |
156 INTEL_PTE_REF | INTEL_PTE_MOD));
157
158 bcopy((void *) ((uintptr_t)src_map->prv_CADDR | ((uint32_t)src64 & INTEL_OFFMASK)),
159 (void *) ((uintptr_t)dst_map->prv_CADDR | ((uint32_t)dst64 & INTEL_OFFMASK)), bytes);
160
161 pmap_put_mapwindow(src_map);
162 pmap_put_mapwindow(dst_map);
163
164 mp_enable_preemption();
165}
166
167/*
168 * allow a function to get a quick virtual mapping of a physical page
169 */
170
171int
172apply_func_phys(
173 addr64_t dst64,
174 vm_size_t bytes,
175 int (*func)(void * buffer, vm_size_t bytes, void * arg),
176 void * arg)
177{
178 mapwindow_t *dst_map;
179 int rc = -1;
180
181 /* ensure we stay within a page */
182 if ( ((((uint32_t)dst64 & (NBPG-1)) + bytes) > NBPG) ) {
183 panic("apply_func_phys alignment");
184 }
185 mp_disable_preemption();
186
187 dst_map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | ((pmap_paddr_t)dst64 & PG_FRAME) |
188 INTEL_PTE_REF | INTEL_PTE_MOD));
189
190 rc = func((void *)((uintptr_t)dst_map->prv_CADDR | ((uint32_t)dst64 & INTEL_OFFMASK)), bytes, arg);
191
192 pmap_put_mapwindow(dst_map);
193
194 mp_enable_preemption();
195
196 return rc;
197}
198
199/*
200 * ovbcopy - like bcopy, but recognizes overlapping ranges and handles
201 * them correctly.
202 */
203
204void
205ovbcopy(
206 const char *from,
207 char *to,
208 vm_size_t bytes) /* num bytes to copy */
209{
210 /* Assume that bcopy copies left-to-right (low addr first). */
211 if (from + bytes <= to || to + bytes <= from || to == from)
212 bcopy_no_overwrite(from, to, bytes); /* non-overlapping or no-op*/
213 else if (from > to)
214 bcopy_no_overwrite(from, to, bytes); /* overlapping but OK */
215 else {
216 /* to > from: overlapping, and must copy right-to-left. */
217 from += bytes - 1;
218 to += bytes - 1;
219 while (bytes-- > 0)
220 *to-- = *from--;
221 }
222}
223
224
225/*
226 * Read data from a physical address.
227 */
228
229
230static unsigned int
231ml_phys_read_data(pmap_paddr_t paddr, int size )
232{
233 mapwindow_t *map;
234 unsigned int result;
235
236 mp_disable_preemption();
237
238 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME) | INTEL_PTE_REF));
239
240 switch (size) {
241 unsigned char s1;
242 unsigned short s2;
243 case 1:
244 s1 = *(unsigned char *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
245 result = s1;
246 break;
247 case 2:
248 s2 = *(unsigned short *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
249 result = s2;
250 break;
251 case 4:
252 default:
253 result = *(unsigned int *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
254 break;
255 }
256 pmap_put_mapwindow(map);
257
258 mp_enable_preemption();
259
260 return result;
261}
262
263static unsigned long long
264ml_phys_read_long_long(pmap_paddr_t paddr )
265{
266 mapwindow_t *map;
267 unsigned long long result;
268
269 mp_disable_preemption();
270
271 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | (paddr & PG_FRAME) | INTEL_PTE_REF));
272
273 result = *(unsigned long long *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK));
274
275 pmap_put_mapwindow(map);
276
277 mp_enable_preemption();
278
279 return result;
280}
281
282unsigned int ml_phys_read( vm_offset_t paddr)
283{
284 return ml_phys_read_data((pmap_paddr_t)paddr, 4);
285}
286
287unsigned int ml_phys_read_word(vm_offset_t paddr) {
288
289 return ml_phys_read_data((pmap_paddr_t)paddr, 4);
290}
291
292unsigned int ml_phys_read_64(addr64_t paddr64)
293{
294 return ml_phys_read_data((pmap_paddr_t)paddr64, 4);
295}
296
297unsigned int ml_phys_read_word_64(addr64_t paddr64)
298{
299 return ml_phys_read_data((pmap_paddr_t)paddr64, 4);
300}
301
302unsigned int ml_phys_read_half(vm_offset_t paddr)
303{
304 return ml_phys_read_data((pmap_paddr_t)paddr, 2);
305}
306
307unsigned int ml_phys_read_half_64(addr64_t paddr64)
308{
309 return ml_phys_read_data((pmap_paddr_t)paddr64, 2);
310}
311
312unsigned int ml_phys_read_byte(vm_offset_t paddr)
313{
314 return ml_phys_read_data((pmap_paddr_t)paddr, 1);
315}
316
317unsigned int ml_phys_read_byte_64(addr64_t paddr64)
318{
319 return ml_phys_read_data((pmap_paddr_t)paddr64, 1);
320}
321
322unsigned long long ml_phys_read_double(vm_offset_t paddr)
323{
324 return ml_phys_read_long_long((pmap_paddr_t)paddr);
325}
326
327unsigned long long ml_phys_read_double_64(addr64_t paddr64)
328{
329 return ml_phys_read_long_long((pmap_paddr_t)paddr64);
330}
331
332
333
334/*
335 * Write data to a physical address.
336 */
337
338static void
339ml_phys_write_data(pmap_paddr_t paddr, unsigned long data, int size)
340{
341 mapwindow_t *map;
342
343 mp_disable_preemption();
344
345 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (paddr & PG_FRAME) |
346 INTEL_PTE_REF | INTEL_PTE_MOD));
347
348 switch (size) {
349 case 1:
350 *(unsigned char *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = (unsigned char)data;
351 break;
352 case 2:
353 *(unsigned short *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = (unsigned short)data;
354 break;
355 case 4:
356 default:
357 *(unsigned int *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = (uint32_t)data;
358 break;
359 }
360 pmap_put_mapwindow(map);
361
362 mp_enable_preemption();
363}
364
365static void
366ml_phys_write_long_long(pmap_paddr_t paddr, unsigned long long data)
367{
368 mapwindow_t *map;
369
370 mp_disable_preemption();
371
372 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (paddr & PG_FRAME) |
373 INTEL_PTE_REF | INTEL_PTE_MOD));
374
375 *(unsigned long long *)((uintptr_t)map->prv_CADDR | ((uint32_t)paddr & INTEL_OFFMASK)) = data;
376
377 pmap_put_mapwindow(map);
378
379 mp_enable_preemption();
380}
381
382
383
384void ml_phys_write_byte(vm_offset_t paddr, unsigned int data)
385{
386 ml_phys_write_data((pmap_paddr_t)paddr, data, 1);
387}
388
389void ml_phys_write_byte_64(addr64_t paddr64, unsigned int data)
390{
391 ml_phys_write_data((pmap_paddr_t)paddr64, data, 1);
392}
393
394void ml_phys_write_half(vm_offset_t paddr, unsigned int data)
395{
396 ml_phys_write_data((pmap_paddr_t)paddr, data, 2);
397}
398
399void ml_phys_write_half_64(addr64_t paddr64, unsigned int data)
400{
401 ml_phys_write_data((pmap_paddr_t)paddr64, data, 2);
402}
403
404void ml_phys_write(vm_offset_t paddr, unsigned int data)
405{
406 ml_phys_write_data((pmap_paddr_t)paddr, data, 4);
407}
408
409void ml_phys_write_64(addr64_t paddr64, unsigned int data)
410{
411 ml_phys_write_data((pmap_paddr_t)paddr64, data, 4);
412}
413
414void ml_phys_write_word(vm_offset_t paddr, unsigned int data)
415{
416 ml_phys_write_data((pmap_paddr_t)paddr, data, 4);
417}
418
419void ml_phys_write_word_64(addr64_t paddr64, unsigned int data)
420{
421 ml_phys_write_data((pmap_paddr_t)paddr64, data, 4);
422}
423
424void ml_phys_write_double(vm_offset_t paddr, unsigned long long data)
425{
426 ml_phys_write_long_long((pmap_paddr_t)paddr, data);
427}
428
429void ml_phys_write_double_64(addr64_t paddr64, unsigned long long data)
430{
431 ml_phys_write_long_long((pmap_paddr_t)paddr64, data);
432}
433
434
435/* PCI config cycle probing
436 *
437 *
438 * Read the memory location at physical address paddr.
439 * This is a part of a device probe, so there is a good chance we will
440 * have a machine check here. So we have to be able to handle that.
441 * We assume that machine checks are enabled both in MSR and HIDs
442 */
443
444boolean_t
445ml_probe_read(vm_offset_t paddr, unsigned int *val)
446{
447 if ((PAGE_SIZE - (paddr & PAGE_MASK)) < 4)
448 return FALSE;
449
450 *val = ml_phys_read(paddr);
451
452 return TRUE;
453}
454
455/*
456 * Read the memory location at physical address paddr.
457 * This is a part of a device probe, so there is a good chance we will
458 * have a machine check here. So we have to be able to handle that.
459 * We assume that machine checks are enabled both in MSR and HIDs
460 */
461boolean_t
462ml_probe_read_64(addr64_t paddr64, unsigned int *val)
463{
464 if ((PAGE_SIZE - (paddr64 & PAGE_MASK)) < 4)
465 return FALSE;
466
467 *val = ml_phys_read_64((pmap_paddr_t)paddr64);
468 return TRUE;
469}
470
471
472int bcmp(
473 const void *pa,
474 const void *pb,
475 size_t len)
476{
477 const char *a = (const char *)pa;
478 const char *b = (const char *)pb;
479
480 if (len == 0)
481 return 0;
482
483 do
484 if (*a++ != *b++)
485 break;
486 while (--len);
487
488 return (int)len;
489}
490
491int
492memcmp(const void *s1, const void *s2, size_t n)
493{
494 if (n != 0) {
495 const unsigned char *p1 = s1, *p2 = s2;
496
497 do {
498 if (*p1++ != *p2++)
499 return (*--p1 - *--p2);
500 } while (--n != 0);
501 }
502 return (0);
503}
504
505/*
506 * Abstract:
507 * strlen returns the number of characters in "string" preceeding
508 * the terminating null character.
509 */
510
511size_t
512strlen(
513 register const char *string)
514{
515 register const char *ret = string;
516
517 while (*string++ != '\0')
518 continue;
519 return string - 1 - ret;
520}
521
522uint32_t
523hw_compare_and_store(uint32_t oldval, uint32_t newval, volatile uint32_t *dest)
524{
525 return OSCompareAndSwap((UInt32)oldval,
526 (UInt32)newval,
527 (volatile UInt32 *)dest);
528}
529
530#if MACH_ASSERT
531
532/*
533 * Machine-dependent routine to fill in an array with up to callstack_max
534 * levels of return pc information.
535 */
536void machine_callstack(
537 __unused natural_t *buf,
538 __unused vm_size_t callstack_max)
539{
540}
541
542#endif /* MACH_ASSERT */
543
544void fillPage(ppnum_t pa, unsigned int fill)
545{
546 mapwindow_t *map;
547 pmap_paddr_t src;
548 int i;
549 int cnt = PAGE_SIZE/sizeof(unsigned int);
550 unsigned int *addr;
551
552 mp_disable_preemption();
553
554 src = i386_ptob(pa);
555 map = pmap_get_mapwindow((pt_entry_t)(INTEL_PTE_VALID | INTEL_PTE_RW | (src & PG_FRAME) |
556 INTEL_PTE_REF | INTEL_PTE_MOD));
557
558 for (i = 0, addr = (unsigned int *)map->prv_CADDR; i < cnt ; i++ )
559 *addr++ = fill;
560
561 pmap_put_mapwindow(map);
562
563 mp_enable_preemption();
564}
565
566static inline void __sfence(void)
567{
568 __asm__ volatile("sfence");
569}
570static inline void __mfence(void)
571{
572 __asm__ volatile("mfence");
573}
574static inline void __wbinvd(void)
575{
576 __asm__ volatile("wbinvd");
577}
578static inline void __clflush(void *ptr)
579{
580 __asm__ volatile("clflush (%0)" : : "r" (ptr));
581}
582
583void dcache_incoherent_io_store64(addr64_t pa, unsigned int count)
584{
585 mapwindow_t *map;
586 uint32_t linesize = cpuid_info()->cache_linesize;
587 addr64_t addr;
588 uint32_t offset, chunk;
589 boolean_t istate;
590
591 __mfence();
592
593 istate = ml_set_interrupts_enabled(FALSE);
594
595 offset = (uint32_t)(pa & (linesize - 1));
596 addr = pa - offset;
597
598 map = pmap_get_mapwindow((pt_entry_t)(i386_ptob(atop_64(addr)) | INTEL_PTE_VALID));
599
600 count += offset;
601 offset = (uint32_t)(addr & ((addr64_t) (page_size - 1)));
602 chunk = (uint32_t)page_size - offset;
603
604 do
605 {
606 if (chunk > count)
607 chunk = count;
608
609 for (; offset < chunk; offset += linesize)
610 __clflush((void *)(((uintptr_t)map->prv_CADDR) + offset));
611
612 count -= chunk;
613 addr += chunk;
614 chunk = (uint32_t) page_size;
615 offset = 0;
616
617 if (count) {
618 pmap_store_pte(map->prv_CMAP, (pt_entry_t)(i386_ptob(atop_64(addr)) | INTEL_PTE_VALID));
619 invlpg((uintptr_t)map->prv_CADDR);
620 }
621 }
622 while (count);
623
624 pmap_put_mapwindow(map);
625
626 (void) ml_set_interrupts_enabled(istate);
627
628 __mfence();
629}
630
631void dcache_incoherent_io_flush64(addr64_t pa, unsigned int count)
632{
633 return(dcache_incoherent_io_store64(pa,count));
634}
635
636
637void
638flush_dcache64(addr64_t addr, unsigned count, int phys)
639{
640 if (phys) {
641 dcache_incoherent_io_flush64(addr, count);
642 }
643 else {
644 uint32_t linesize = cpuid_info()->cache_linesize;
645 addr64_t bound = (addr + count + linesize - 1) & ~(linesize - 1);
646 __mfence();
647 while (addr < bound) {
648 __clflush((void *) (uintptr_t) addr);
649 addr += linesize;
650 }
651 __mfence();
652 }
653}
654
655void
656invalidate_icache64(__unused addr64_t addr,
657 __unused unsigned count,
658 __unused int phys)
659{
660}
661
662
663addr64_t vm_last_addr;
664
665void
666mapping_set_mod(ppnum_t pn)
667{
668 pmap_set_modify(pn);
669}
670
671void
672mapping_set_ref(ppnum_t pn)
673{
674 pmap_set_reference(pn);
675}
676
677void
678cache_flush_page_phys(ppnum_t pa)
679{
680 mapwindow_t *map;
681 boolean_t istate;
682 int i;
683 unsigned char *cacheline_addr;
684 int cacheline_size = cpuid_info()->cache_linesize;
685 int cachelines_in_page = PAGE_SIZE/cacheline_size;
686
687 __mfence();
688
689 istate = ml_set_interrupts_enabled(FALSE);
690
691 map = pmap_get_mapwindow((pt_entry_t)(i386_ptob(pa) | INTEL_PTE_VALID));
692
693 for (i = 0, cacheline_addr = (unsigned char *)map->prv_CADDR;
694 i < cachelines_in_page;
695 i++, cacheline_addr += cacheline_size) {
696 __clflush((void *) cacheline_addr);
697 }
698 pmap_put_mapwindow(map);
699
700 (void) ml_set_interrupts_enabled(istate);
701
702 __mfence();
703}
704
705
706#if !MACH_KDP
707void
708kdp_register_callout(void)
709{
710}
711#endif
712
713#if !CONFIG_VMX
714int host_vmxon(boolean_t exclusive __unused)
715{
716 return VMX_UNSUPPORTED;
717}
718
719void host_vmxoff(void)
720{
721 return;
722}
723#endif
724
725#ifdef __LP64__
726
727#define INT_SIZE (BYTE_SIZE * sizeof (int))
728
729/*
730 * Set indicated bit in bit string.
731 */
732void
733setbit(int bitno, int *s)
734{
735 s[bitno / INT_SIZE] |= 1 << (bitno % INT_SIZE);
736}
737
738/*
739 * Clear indicated bit in bit string.
740 */
741void
742clrbit(int bitno, int *s)
743{
744 s[bitno / INT_SIZE] &= ~(1 << (bitno % INT_SIZE));
745}
746
747/*
748 * Test if indicated bit is set in bit string.
749 */
750int
751testbit(int bitno, int *s)
752{
753 return s[bitno / INT_SIZE] & (1 << (bitno % INT_SIZE));
754}
755
756/*
757 * Find first bit set in bit string.
758 */
759int
760ffsbit(int *s)
761{
762 int offset;
763
764 for (offset = 0; !*s; offset += (int)INT_SIZE, ++s);
765 return offset + __builtin_ctz(*s);
766}
767
768int
769ffs(unsigned int mask)
770{
771 if (mask == 0)
772 return 0;
773
774 /*
775 * NOTE: cannot use __builtin_ffs because it generates a call to
776 * 'ffs'
777 */
778 return 1 + __builtin_ctz(mask);
779}
780#endif