sljit_src/sljitUtils.c

   1 /*
   2  *    Stack-less Just-In-Time compiler
   3  *
   4  *    Copyright Zoltan Herczeg (hzmester@freemail.hu). All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without modification, are
   7  * permitted provided that the following conditions are met:
   8  *
   9  *   1. Redistributions of source code must retain the above copyright notice, this list of
  10  *      conditions and the following disclaimer.
  11  *
  12  *   2. Redistributions in binary form must reproduce the above copyright notice, this list
  13  *      of conditions and the following disclaimer in the documentation and/or other materials
  14  *      provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
  19  * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
  21  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  22  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  23  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  24  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  25  */
  26
  27 /* ------------------------------------------------------------------------ */
  28 /*  Locks                                                                   */
  29 /* ------------------------------------------------------------------------ */
  30
  31 /* Executable Allocator */
  32
  33 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) \
  34         && !(defined SLJIT_WX_EXECUTABLE_ALLOCATOR && SLJIT_WX_EXECUTABLE_ALLOCATOR)
  35 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
  36 #define SLJIT_ALLOCATOR_LOCK()
  37 #define SLJIT_ALLOCATOR_UNLOCK()
  38 #elif !(defined _WIN32)
  39 #include <pthread.h>
  40
  41 static pthread_mutex_t allocator_lock = PTHREAD_MUTEX_INITIALIZER;
  42
  43 #define SLJIT_ALLOCATOR_LOCK() pthread_mutex_lock(&allocator_lock)
  44 #define SLJIT_ALLOCATOR_UNLOCK() pthread_mutex_unlock(&allocator_lock)
  45 #else /* windows */
  46 static HANDLE allocator_lock;
  47
  48 static SLJIT_INLINE void allocator_grab_lock(void)
  49 {
  50         HANDLE lock;
  51         if (SLJIT_UNLIKELY(!InterlockedCompareExchangePointer(&allocator_lock, NULL, NULL))) {
  52                 lock = CreateMutex(NULL, FALSE, NULL);
  53                 if (InterlockedCompareExchangePointer(&allocator_lock, lock, NULL))
  54                         CloseHandle(lock);
  55         }
  56         WaitForSingleObject(allocator_lock, INFINITE);
  57 }
  58
  59 #define SLJIT_ALLOCATOR_LOCK() allocator_grab_lock()
  60 #define SLJIT_ALLOCATOR_UNLOCK() ReleaseMutex(allocator_lock)
  61 #endif /* thread implementation */
  62 #endif /* SLJIT_EXECUTABLE_ALLOCATOR && !SLJIT_WX_EXECUTABLE_ALLOCATOR */
  63
  64 /* ------------------------------------------------------------------------ */
  65 /*  Stack                                                                   */
  66 /* ------------------------------------------------------------------------ */
  67
  68 #if ((defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) \
  69         && !(defined SLJIT_UTIL_SIMPLE_STACK_ALLOCATION && SLJIT_UTIL_SIMPLE_STACK_ALLOCATION)) \
  70         || ((defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) \
  71         && !((defined SLJIT_PROT_EXECUTABLE_ALLOCATOR && SLJIT_PROT_EXECUTABLE_ALLOCATOR) \
  72         || (defined SLJIT_WX_EXECUTABLE_ALLOCATOR && SLJIT_WX_EXECUTABLE_ALLOCATOR)))
  73
  74 #ifndef _WIN32
  75 /* Provides mmap function. */
  76 #include <sys/types.h>
  77 #include <sys/mman.h>
  78
  79 #ifndef MAP_ANON
  80 #ifdef MAP_ANONYMOUS
  81 #define MAP_ANON MAP_ANONYMOUS
  82 #endif /* MAP_ANONYMOUS */
  83 #endif /* !MAP_ANON */
  84
  85 #ifndef MAP_ANON
  86
  87 #include <fcntl.h>
  88
  89 #ifdef O_CLOEXEC
  90 #define SLJIT_CLOEXEC   O_CLOEXEC
  91 #else /* !O_CLOEXEC */
  92 #define SLJIT_CLOEXEC   0
  93 #endif /* O_CLOEXEC */
  94
  95 /* Some old systems do not have MAP_ANON. */
  96 static int dev_zero = -1;
  97
  98 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
  99
 100 static SLJIT_INLINE int open_dev_zero(void)
 101 {
 102         dev_zero = open("/dev/zero", O_RDWR | SLJIT_CLOEXEC);
 103
 104         return dev_zero < 0;
 105 }
 106
 107 #else /* !SLJIT_SINGLE_THREADED */
 108
 109 #include <pthread.h>
 110
 111 static pthread_mutex_t dev_zero_mutex = PTHREAD_MUTEX_INITIALIZER;
 112
 113 static SLJIT_INLINE int open_dev_zero(void)
 114 {
 115         pthread_mutex_lock(&dev_zero_mutex);
 116         if (SLJIT_UNLIKELY(dev_zero < 0))
 117                 dev_zero = open("/dev/zero", O_RDWR | SLJIT_CLOEXEC);
 118
 119         pthread_mutex_unlock(&dev_zero_mutex);
 120         return dev_zero < 0;
 121 }
 122
 123 #endif /* SLJIT_SINGLE_THREADED */
 124 #undef SLJIT_CLOEXEC
 125 #endif /* !MAP_ANON */
 126 #endif /* !_WIN32 */
 127 #endif /* open_dev_zero */
 128
 129 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) \
 130         || (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
 131
 132 #ifdef _WIN32
 133
 134 static SLJIT_INLINE sljit_uw get_page_alignment(void) {
 135         SYSTEM_INFO si;
 136         static sljit_uw sljit_page_align = 0;
 137         if (!sljit_page_align) {
 138                 GetSystemInfo(&si);
 139                 sljit_page_align = (sljit_uw)si.dwPageSize - 1;
 140         }
 141         return sljit_page_align;
 142 }
 143
 144 #else
 145
 146 #include <unistd.h>
 147
 148 static SLJIT_INLINE sljit_uw get_page_alignment(void) {
 149         static sljit_uw sljit_page_align = 0;
 150
 151         sljit_sw align;
 152
 153         if (!sljit_page_align) {
 154 #ifdef _SC_PAGESIZE
 155                 align = sysconf(_SC_PAGESIZE);
 156 #else
 157                 align = getpagesize();
 158 #endif
 159                 /* Should never happen. */
 160                 if (align < 0)
 161                         align = 4096;
 162                 sljit_page_align = (sljit_uw)align - 1;
 163         }
 164         return sljit_page_align;
 165 }
 166
 167 #endif /* _WIN32 */
 168
 169 #endif /* get_page_alignment() */
 170
 171 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK)
 172
 173 #if (defined SLJIT_UTIL_SIMPLE_STACK_ALLOCATION && SLJIT_UTIL_SIMPLE_STACK_ALLOCATION)
 174
 175 SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_FUNC sljit_allocate_stack(sljit_uw start_size, sljit_uw max_size, void *allocator_data)
 176 {
 177         struct sljit_stack *stack;
 178         void *ptr;
 179
 180         SLJIT_UNUSED_ARG(allocator_data);
 181
 182         if (start_size > max_size || start_size < 1)
 183                 return NULL;
 184
 185         stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data);
 186         if (stack == NULL)
 187                 return NULL;
 188
 189         ptr = SLJIT_MALLOC(max_size, allocator_data);
 190         if (ptr == NULL) {
 191                 SLJIT_FREE(stack, allocator_data);
 192                 return NULL;
 193         }
 194
 195         stack->min_start = (sljit_u8 *)ptr;
 196         stack->end = stack->min_start + max_size;
 197         stack->start = stack->end - start_size;
 198         stack->top = stack->end;
 199         return stack;
 200 }
 201
 202 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_free_stack(struct sljit_stack *stack, void *allocator_data)
 203 {
 204         SLJIT_UNUSED_ARG(allocator_data);
 205         SLJIT_FREE((void*)stack->min_start, allocator_data);
 206         SLJIT_FREE(stack, allocator_data);
 207 }
 208
 209 SLJIT_API_FUNC_ATTRIBUTE sljit_u8 *SLJIT_FUNC sljit_stack_resize(struct sljit_stack *stack, sljit_u8 *new_start)
 210 {
 211         if ((new_start < stack->min_start) || (new_start >= stack->end))
 212                 return NULL;
 213         stack->start = new_start;
 214         return new_start;
 215 }
 216
 217 #else /* !SLJIT_UTIL_SIMPLE_STACK_ALLOCATION */
 218
 219 #ifdef _WIN32
 220
 221 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_free_stack(struct sljit_stack *stack, void *allocator_data)
 222 {
 223         SLJIT_UNUSED_ARG(allocator_data);
 224         VirtualFree((void*)stack->min_start, 0, MEM_RELEASE);
 225         SLJIT_FREE(stack, allocator_data);
 226 }
 227
 228 #else /* !_WIN32 */
 229
 230 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_FUNC sljit_free_stack(struct sljit_stack *stack, void *allocator_data)
 231 {
 232         SLJIT_UNUSED_ARG(allocator_data);
 233         munmap((void*)stack->min_start, (size_t)(stack->end - stack->min_start));
 234         SLJIT_FREE(stack, allocator_data);
 235 }
 236
 237 #endif /* _WIN32 */
 238
 239 SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_FUNC sljit_allocate_stack(sljit_uw start_size, sljit_uw max_size, void *allocator_data)
 240 {
 241         struct sljit_stack *stack;
 242         void *ptr;
 243         sljit_uw page_align;
 244
 245         SLJIT_UNUSED_ARG(allocator_data);
 246
 247         if (start_size > max_size || start_size < 1)
 248                 return NULL;
 249
 250         stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data);
 251         if (stack == NULL)
 252                 return NULL;
 253
 254         /* Align max_size. */
 255         page_align = get_page_alignment();
 256         max_size = (max_size + page_align) & ~page_align;
 257
 258 #ifdef _WIN32
 259         ptr = VirtualAlloc(NULL, max_size, MEM_RESERVE, PAGE_READWRITE);
 260         if (!ptr) {
 261                 SLJIT_FREE(stack, allocator_data);
 262                 return NULL;
 263         }
 264
 265         stack->min_start = (sljit_u8 *)ptr;
 266         stack->end = stack->min_start + max_size;
 267         stack->start = stack->end;
 268
 269         if (sljit_stack_resize(stack, stack->end - start_size) == NULL) {
 270                 sljit_free_stack(stack, allocator_data);
 271                 return NULL;
 272         }
 273 #else /* !_WIN32 */
 274 #ifdef MAP_ANON
 275         ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
 276 #else /* !MAP_ANON */
 277         if (SLJIT_UNLIKELY((dev_zero < 0) && open_dev_zero())) {
 278                 SLJIT_FREE(stack, allocator_data);
 279                 return NULL;
 280         }
 281         ptr = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, dev_zero, 0);
 282 #endif /* MAP_ANON */
 283         if (ptr == MAP_FAILED) {
 284                 SLJIT_FREE(stack, allocator_data);
 285                 return NULL;
 286         }
 287         stack->min_start = (sljit_u8 *)ptr;
 288         stack->end = stack->min_start + max_size;
 289         stack->start = stack->end - start_size;
 290 #endif /* _WIN32 */
 291
 292         stack->top = stack->end;
 293         return stack;
 294 }
 295
 296 SLJIT_API_FUNC_ATTRIBUTE sljit_u8 *SLJIT_FUNC sljit_stack_resize(struct sljit_stack *stack, sljit_u8 *new_start)
 297 {
 298 #if defined _WIN32 || defined(POSIX_MADV_DONTNEED)
 299         sljit_uw aligned_old_start;
 300         sljit_uw aligned_new_start;
 301         sljit_uw page_align;
 302 #endif
 303
 304         if ((new_start < stack->min_start) || (new_start >= stack->end))
 305                 return NULL;
 306
 307 #ifdef _WIN32
 308         page_align = get_page_alignment();
 309
 310         aligned_new_start = (sljit_uw)new_start & ~page_align;
 311         aligned_old_start = ((sljit_uw)stack->start) & ~page_align;
 312         if (aligned_new_start != aligned_old_start) {
 313                 if (aligned_new_start < aligned_old_start) {
 314                         if (!VirtualAlloc((void*)aligned_new_start, aligned_old_start - aligned_new_start, MEM_COMMIT, PAGE_READWRITE))
 315                                 return NULL;
 316                 }
 317                 else {
 318                         if (!VirtualFree((void*)aligned_old_start, aligned_new_start - aligned_old_start, MEM_DECOMMIT))
 319                                 return NULL;
 320                 }
 321         }
 322 #elif defined(POSIX_MADV_DONTNEED)
 323         if (stack->start < new_start) {
 324                 page_align = get_page_alignment();
 325
 326                 aligned_new_start = (sljit_uw)new_start & ~page_align;
 327                 aligned_old_start = ((sljit_uw)stack->start) & ~page_align;
 328
 329                 if (aligned_new_start > aligned_old_start) {
 330                         posix_madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, POSIX_MADV_DONTNEED);
 331 #ifdef MADV_FREE
 332                         madvise((void*)aligned_old_start, aligned_new_start - aligned_old_start, MADV_FREE);
 333 #endif /* MADV_FREE */
 334                 }
 335         }
 336 #endif /* _WIN32 */
 337
 338         stack->start = new_start;
 339         return new_start;
 340 }
 341
 342 #endif /* SLJIT_UTIL_SIMPLE_STACK_ALLOCATION */
 343
 344 #endif /* SLJIT_UTIL_STACK */