1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
|
//===- bolt/runtime/common.h ------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#if !defined(__APPLE__)
#include <cstddef>
#include <cstdint>
#include "config.h"
#ifdef HAVE_ELF_H
#include <elf.h>
#endif
#else
typedef __SIZE_TYPE__ size_t;
#define __SSIZE_TYPE__ \
__typeof__(_Generic((__SIZE_TYPE__)0, unsigned long long int \
: (long long int)0, unsigned long int \
: (long int)0, unsigned int \
: (int)0, unsigned short \
: (short)0, unsigned char \
: (signed char)0))
typedef __SSIZE_TYPE__ ssize_t;
typedef unsigned long long uint64_t;
typedef unsigned uint32_t;
typedef unsigned char uint8_t;
typedef long long int64_t;
typedef int int32_t;
#endif
// Save all registers while keeping 16B stack alignment
#define SAVE_ALL \
"push %%rax\n" \
"push %%rbx\n" \
"push %%rcx\n" \
"push %%rdx\n" \
"push %%rdi\n" \
"push %%rsi\n" \
"push %%rbp\n" \
"push %%r8\n" \
"push %%r9\n" \
"push %%r10\n" \
"push %%r11\n" \
"push %%r12\n" \
"push %%r13\n" \
"push %%r14\n" \
"push %%r15\n" \
"sub $8, %%rsp\n"
// Mirrors SAVE_ALL
#define RESTORE_ALL \
"add $8, %%rsp\n" \
"pop %%r15\n" \
"pop %%r14\n" \
"pop %%r13\n" \
"pop %%r12\n" \
"pop %%r11\n" \
"pop %%r10\n" \
"pop %%r9\n" \
"pop %%r8\n" \
"pop %%rbp\n" \
"pop %%rsi\n" \
"pop %%rdi\n" \
"pop %%rdx\n" \
"pop %%rcx\n" \
"pop %%rbx\n" \
"pop %%rax\n"
// Functions that are required by freestanding environment. Compiler may
// generate calls to these implicitly.
extern "C" {
void *memcpy(void *Dest, const void *Src, size_t Len) {
uint8_t *d = static_cast<uint8_t *>(Dest);
const uint8_t *s = static_cast<const uint8_t *>(Src);
while (Len--)
*d++ = *s++;
return Dest;
}
void *memmove(void *Dest, const void *Src, size_t Len) {
uint8_t *d = static_cast<uint8_t *>(Dest);
const uint8_t *s = static_cast<const uint8_t *>(Src);
if (d < s) {
while (Len--)
*d++ = *s++;
} else {
s += Len - 1;
d += Len - 1;
while (Len--)
*d-- = *s--;
}
return Dest;
}
void *memset(void *Buf, int C, size_t Size) {
char *S = (char *)Buf;
for (size_t I = 0; I < Size; ++I)
*S++ = C;
return Buf;
}
int memcmp(const void *s1, const void *s2, size_t n) {
const uint8_t *c1 = static_cast<const uint8_t *>(s1);
const uint8_t *c2 = static_cast<const uint8_t *>(s2);
for (; n--; c1++, c2++) {
if (*c1 != *c2)
return *c1 < *c2 ? -1 : 1;
}
return 0;
}
} // extern "C"
// Anonymous namespace covering everything but our library entry point
namespace {
constexpr uint32_t BufSize = 10240;
#define _STRINGIFY(x) #x
#define STRINGIFY(x) _STRINGIFY(x)
uint64_t __read(uint64_t fd, const void *buf, uint64_t count) {
uint64_t ret;
#if defined(__APPLE__)
#define READ_SYSCALL 0x2000003
#else
#define READ_SYSCALL 0
#endif
__asm__ __volatile__("movq $" STRINGIFY(READ_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(fd), "S"(buf), "d"(count)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __write(uint64_t fd, const void *buf, uint64_t count) {
uint64_t ret;
#if defined(__APPLE__)
#define WRITE_SYSCALL 0x2000004
#else
#define WRITE_SYSCALL 1
#endif
__asm__ __volatile__("movq $" STRINGIFY(WRITE_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(fd), "S"(buf), "d"(count)
: "cc", "rcx", "r11", "memory");
return ret;
}
void *__mmap(uint64_t addr, uint64_t size, uint64_t prot, uint64_t flags,
uint64_t fd, uint64_t offset) {
#if defined(__APPLE__)
#define MMAP_SYSCALL 0x20000c5
#else
#define MMAP_SYSCALL 9
#endif
void *ret;
register uint64_t r8 asm("r8") = fd;
register uint64_t r9 asm("r9") = offset;
register uint64_t r10 asm("r10") = flags;
__asm__ __volatile__("movq $" STRINGIFY(MMAP_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(addr), "S"(size), "d"(prot), "r"(r10), "r"(r8),
"r"(r9)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __munmap(void *addr, uint64_t size) {
#if defined(__APPLE__)
#define MUNMAP_SYSCALL 0x2000049
#else
#define MUNMAP_SYSCALL 11
#endif
uint64_t ret;
__asm__ __volatile__("movq $" STRINGIFY(MUNMAP_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(addr), "S"(size)
: "cc", "rcx", "r11", "memory");
return ret;
}
#define SIG_BLOCK 0
#define SIG_UNBLOCK 1
#define SIG_SETMASK 2
static const uint64_t MaskAllSignals[] = {-1ULL};
uint64_t __sigprocmask(int how, const void *set, void *oldset) {
#if defined(__APPLE__)
#define SIGPROCMASK_SYSCALL 0x2000030
#else
#define SIGPROCMASK_SYSCALL 14
#endif
uint64_t ret;
register long r10 asm("r10") = sizeof(uint64_t);
__asm__ __volatile__("movq $" STRINGIFY(SIGPROCMASK_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(how), "S"(set), "d"(oldset), "r"(r10)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __exit(uint64_t code) {
#if defined(__APPLE__)
#define EXIT_SYSCALL 0x2000001
#else
#define EXIT_SYSCALL 231
#endif
uint64_t ret;
__asm__ __volatile__("movq $" STRINGIFY(EXIT_SYSCALL) ", %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(code)
: "cc", "rcx", "r11", "memory");
return ret;
}
// Helper functions for writing strings to the .fdata file. We intentionally
// avoid using libc names to make it clear it is our impl.
/// Write number Num using Base to the buffer in OutBuf, returns a pointer to
/// the end of the string.
char *intToStr(char *OutBuf, uint64_t Num, uint32_t Base) {
const char *Chars = "0123456789abcdef";
char Buf[21];
char *Ptr = Buf;
while (Num) {
*Ptr++ = *(Chars + (Num % Base));
Num /= Base;
}
if (Ptr == Buf) {
*OutBuf++ = '0';
return OutBuf;
}
while (Ptr != Buf)
*OutBuf++ = *--Ptr;
return OutBuf;
}
/// Copy Str to OutBuf, returns a pointer to the end of the copied string
char *strCopy(char *OutBuf, const char *Str, int32_t Size = BufSize) {
while (*Str) {
*OutBuf++ = *Str++;
if (--Size <= 0)
return OutBuf;
}
return OutBuf;
}
/// Compare two strings, at most Num bytes.
int strnCmp(const char *Str1, const char *Str2, size_t Num) {
while (Num && *Str1 && (*Str1 == *Str2)) {
Num--;
Str1++;
Str2++;
}
if (Num == 0)
return 0;
return *(unsigned char *)Str1 - *(unsigned char *)Str2;
}
uint32_t strLen(const char *Str) {
uint32_t Size = 0;
while (*Str++)
++Size;
return Size;
}
void *strStr(const char *const Haystack, const char *const Needle) {
int j = 0;
for (int i = 0; i < strLen(Haystack); i++) {
if (Haystack[i] == Needle[0]) {
for (j = 1; j < strLen(Needle); j++) {
if (Haystack[i + j] != Needle[j])
break;
}
if (j == strLen(Needle))
return (void *)&Haystack[i];
}
}
return nullptr;
}
void reportNumber(const char *Msg, uint64_t Num, uint32_t Base) {
char Buf[BufSize];
char *Ptr = Buf;
Ptr = strCopy(Ptr, Msg, BufSize - 23);
Ptr = intToStr(Ptr, Num, Base);
Ptr = strCopy(Ptr, "\n");
__write(2, Buf, Ptr - Buf);
}
void report(const char *Msg) { __write(2, Msg, strLen(Msg)); }
unsigned long hexToLong(const char *Str, char Terminator = '\0') {
unsigned long Res = 0;
while (*Str != Terminator) {
Res <<= 4;
if ('0' <= *Str && *Str <= '9')
Res += *Str++ - '0';
else if ('a' <= *Str && *Str <= 'f')
Res += *Str++ - 'a' + 10;
else if ('A' <= *Str && *Str <= 'F')
Res += *Str++ - 'A' + 10;
else
return 0;
}
return Res;
}
/// Starting from character at \p buf, find the longest consecutive sequence
/// of digits (0-9) and convert it to uint32_t. The converted value
/// is put into \p ret. \p end marks the end of the buffer to avoid buffer
/// overflow. The function \returns whether a valid uint32_t value is found.
/// \p buf will be updated to the next character right after the digits.
static bool scanUInt32(const char *&Buf, const char *End, uint32_t &Ret) {
uint64_t Result = 0;
const char *OldBuf = Buf;
while (Buf < End && ((*Buf) >= '0' && (*Buf) <= '9')) {
Result = Result * 10 + (*Buf) - '0';
++Buf;
}
if (OldBuf != Buf && Result <= 0xFFFFFFFFu) {
Ret = static_cast<uint32_t>(Result);
return true;
}
return false;
}
#if !defined(__APPLE__)
// We use a stack-allocated buffer for string manipulation in many pieces of
// this code, including the code that prints each line of the fdata file. This
// buffer needs to accomodate large function names, but shouldn't be arbitrarily
// large (dynamically allocated) for simplicity of our memory space usage.
// Declare some syscall wrappers we use throughout this code to avoid linking
// against system libc.
uint64_t __open(const char *pathname, uint64_t flags, uint64_t mode) {
uint64_t ret;
__asm__ __volatile__("movq $2, %%rax\n"
"syscall"
: "=a"(ret)
: "D"(pathname), "S"(flags), "d"(mode)
: "cc", "rcx", "r11", "memory");
return ret;
}
struct dirent {
unsigned long d_ino; /* Inode number */
unsigned long d_off; /* Offset to next linux_dirent */
unsigned short d_reclen; /* Length of this linux_dirent */
char d_name[]; /* Filename (null-terminated) */
/* length is actually (d_reclen - 2 -
offsetof(struct linux_dirent, d_name)) */
};
long __getdents(unsigned int fd, dirent *dirp, size_t count) {
long ret;
__asm__ __volatile__("movq $78, %%rax\n"
"syscall"
: "=a"(ret)
: "D"(fd), "S"(dirp), "d"(count)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __readlink(const char *pathname, char *buf, size_t bufsize) {
uint64_t ret;
__asm__ __volatile__("movq $89, %%rax\n"
"syscall"
: "=a"(ret)
: "D"(pathname), "S"(buf), "d"(bufsize)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __lseek(uint64_t fd, uint64_t pos, uint64_t whence) {
uint64_t ret;
__asm__ __volatile__("movq $8, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(fd), "S"(pos), "d"(whence)
: "cc", "rcx", "r11", "memory");
return ret;
}
int __close(uint64_t fd) {
uint64_t ret;
__asm__ __volatile__("movq $3, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(fd)
: "cc", "rcx", "r11", "memory");
return ret;
}
int __madvise(void *addr, size_t length, int advice) {
int ret;
__asm__ __volatile__("movq $28, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(addr), "S"(length), "d"(advice)
: "cc", "rcx", "r11", "memory");
return ret;
}
#define _UTSNAME_LENGTH 65
struct UtsNameTy {
char sysname[_UTSNAME_LENGTH]; /* Operating system name (e.g., "Linux") */
char nodename[_UTSNAME_LENGTH]; /* Name within "some implementation-defined
network" */
char release[_UTSNAME_LENGTH]; /* Operating system release (e.g., "2.6.28") */
char version[_UTSNAME_LENGTH]; /* Operating system version */
char machine[_UTSNAME_LENGTH]; /* Hardware identifier */
char domainname[_UTSNAME_LENGTH]; /* NIS or YP domain name */
};
int __uname(struct UtsNameTy *Buf) {
int Ret;
__asm__ __volatile__("movq $63, %%rax\n"
"syscall\n"
: "=a"(Ret)
: "D"(Buf)
: "cc", "rcx", "r11", "memory");
return Ret;
}
struct timespec {
uint64_t tv_sec; /* seconds */
uint64_t tv_nsec; /* nanoseconds */
};
uint64_t __nanosleep(const timespec *req, timespec *rem) {
uint64_t ret;
__asm__ __volatile__("movq $35, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(req), "S"(rem)
: "cc", "rcx", "r11", "memory");
return ret;
}
int64_t __fork() {
uint64_t ret;
__asm__ __volatile__("movq $57, %%rax\n"
"syscall\n"
: "=a"(ret)
:
: "cc", "rcx", "r11", "memory");
return ret;
}
int __mprotect(void *addr, size_t len, int prot) {
int ret;
__asm__ __volatile__("movq $10, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(addr), "S"(len), "d"(prot)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __getpid() {
uint64_t ret;
__asm__ __volatile__("movq $39, %%rax\n"
"syscall\n"
: "=a"(ret)
:
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __getppid() {
uint64_t ret;
__asm__ __volatile__("movq $110, %%rax\n"
"syscall\n"
: "=a"(ret)
:
: "cc", "rcx", "r11", "memory");
return ret;
}
int __setpgid(uint64_t pid, uint64_t pgid) {
int ret;
__asm__ __volatile__("movq $109, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(pid), "S"(pgid)
: "cc", "rcx", "r11", "memory");
return ret;
}
uint64_t __getpgid(uint64_t pid) {
uint64_t ret;
__asm__ __volatile__("movq $121, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(pid)
: "cc", "rcx", "r11", "memory");
return ret;
}
int __kill(uint64_t pid, int sig) {
int ret;
__asm__ __volatile__("movq $62, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(pid), "S"(sig)
: "cc", "rcx", "r11", "memory");
return ret;
}
int __fsync(int fd) {
int ret;
__asm__ __volatile__("movq $74, %%rax\n"
"syscall\n"
: "=a"(ret)
: "D"(fd)
: "cc", "rcx", "r11", "memory");
return ret;
}
// %rdi %rsi %rdx %r10 %r8
// sys_prctl int option unsigned unsigned unsigned unsigned
// long arg2 long arg3 long arg4 long arg5
int __prctl(int Option, unsigned long Arg2, unsigned long Arg3,
unsigned long Arg4, unsigned long Arg5) {
int Ret;
register long rdx asm("rdx") = Arg3;
register long r8 asm("r8") = Arg5;
register long r10 asm("r10") = Arg4;
__asm__ __volatile__("movq $157, %%rax\n"
"syscall\n"
: "=a"(Ret)
: "D"(Option), "S"(Arg2), "d"(rdx), "r"(r10), "r"(r8)
:);
return Ret;
}
#endif
void reportError(const char *Msg, uint64_t Size) {
__write(2, Msg, Size);
__exit(1);
}
void assert(bool Assertion, const char *Msg) {
if (Assertion)
return;
char Buf[BufSize];
char *Ptr = Buf;
Ptr = strCopy(Ptr, "Assertion failed: ");
Ptr = strCopy(Ptr, Msg, BufSize - 40);
Ptr = strCopy(Ptr, "\n");
reportError(Buf, Ptr - Buf);
}
class Mutex {
volatile bool InUse{false};
public:
bool acquire() { return !__atomic_test_and_set(&InUse, __ATOMIC_ACQUIRE); }
void release() { __atomic_clear(&InUse, __ATOMIC_RELEASE); }
};
/// RAII wrapper for Mutex
class Lock {
Mutex &M;
uint64_t SignalMask[1] = {};
public:
Lock(Mutex &M) : M(M) {
__sigprocmask(SIG_BLOCK, MaskAllSignals, SignalMask);
while (!M.acquire()) {
}
}
~Lock() {
M.release();
__sigprocmask(SIG_SETMASK, SignalMask, nullptr);
}
};
/// RAII wrapper for Mutex
class TryLock {
Mutex &M;
bool Locked = false;
public:
TryLock(Mutex &M) : M(M) {
int Retry = 100;
while (--Retry && !M.acquire())
;
if (Retry)
Locked = true;
}
bool isLocked() { return Locked; }
~TryLock() {
if (isLocked())
M.release();
}
};
inline uint64_t alignTo(uint64_t Value, uint64_t Align) {
return (Value + Align - 1) / Align * Align;
}
} // anonymous namespace
|