1 /*        $NetBSD: sljitUtils.c,v 1.11 2020/09/05 16:30:11 riastradh Exp $      */
2 
3 /*
4  *    Stack-less Just-In-Time compiler
5  *
6  *    Copyright Zoltan Herczeg (hzmester@freemail.hu). All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without modification, are
9  * permitted provided that the following conditions are met:
10  *
11  *   1. Redistributions of source code must retain the above copyright notice, this list of
12  *      conditions and the following disclaimer.
13  *
14  *   2. Redistributions in binary form must reproduce the above copyright notice, this list
15  *      of conditions and the following disclaimer in the documentation and/or other materials
16  *      provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) AND CONTRIBUTORS ``AS IS'' AND ANY
19  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
21  * SHALL THE COPYRIGHT HOLDER(S) OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
23  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
24  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
25  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
26  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /* ------------------------------------------------------------------------ */
30 /*  Locks                                                                   */
31 /* ------------------------------------------------------------------------ */
32 
33 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR) || (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
34 
35 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
36 
37 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
38 
allocator_grab_lock(void)39 static SLJIT_INLINE void allocator_grab_lock(void)
40 {
41           /* Always successful. */
42 }
43 
allocator_release_lock(void)44 static SLJIT_INLINE void allocator_release_lock(void)
45 {
46           /* Always successful. */
47 }
48 
49 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
50 
51 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
52 
sljit_grab_lock(void)53 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_grab_lock(void)
54 {
55           /* Always successful. */
56 }
57 
sljit_release_lock(void)58 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_release_lock(void)
59 {
60           /* Always successful. */
61 }
62 
63 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
64 
65 #elif defined(_WIN32) /* SLJIT_SINGLE_THREADED */
66 
67 #include "windows.h"
68 
69 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
70 
71 static HANDLE allocator_mutex = 0;
72 
allocator_grab_lock(void)73 static SLJIT_INLINE void allocator_grab_lock(void)
74 {
75           /* No idea what to do if an error occures. Static mutexes should never fail... */
76           if (!allocator_mutex)
77                     allocator_mutex = CreateMutex(NULL, TRUE, NULL);
78           else
79                     WaitForSingleObject(allocator_mutex, INFINITE);
80 }
81 
allocator_release_lock(void)82 static SLJIT_INLINE void allocator_release_lock(void)
83 {
84           ReleaseMutex(allocator_mutex);
85 }
86 
87 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
88 
89 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
90 
91 static HANDLE global_mutex = 0;
92 
sljit_grab_lock(void)93 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_grab_lock(void)
94 {
95           /* No idea what to do if an error occures. Static mutexes should never fail... */
96           if (!global_mutex)
97                     global_mutex = CreateMutex(NULL, TRUE, NULL);
98           else
99                     WaitForSingleObject(global_mutex, INFINITE);
100 }
101 
sljit_release_lock(void)102 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_release_lock(void)
103 {
104           ReleaseMutex(global_mutex);
105 }
106 
107 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
108 
109 #else /* _WIN32 */
110 
111 #if (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
112 
113 #ifdef _KERNEL
114 
115 #include <sys/mutex.h>
116 
117 /* Defined in sljit_mod.c */
118 extern kmutex_t sljit_allocator_mutex;
119 
allocator_grab_lock(void)120 static SLJIT_INLINE void allocator_grab_lock(void)
121 {
122           mutex_enter(&sljit_allocator_mutex);
123 }
124 
allocator_release_lock(void)125 static SLJIT_INLINE void allocator_release_lock(void)
126 {
127           mutex_exit(&sljit_allocator_mutex);
128 }
129 #else
130 
131 #include <pthread.h>
132 
133 static pthread_mutex_t allocator_mutex = PTHREAD_MUTEX_INITIALIZER;
134 
allocator_grab_lock(void)135 static SLJIT_INLINE void allocator_grab_lock(void)
136 {
137           pthread_mutex_lock(&allocator_mutex);
138 }
139 
allocator_release_lock(void)140 static SLJIT_INLINE void allocator_release_lock(void)
141 {
142           pthread_mutex_unlock(&allocator_mutex);
143 }
144 #endif
145 
146 #endif /* SLJIT_EXECUTABLE_ALLOCATOR */
147 
148 #if (defined SLJIT_UTIL_GLOBAL_LOCK && SLJIT_UTIL_GLOBAL_LOCK)
149 
150 #ifdef _KERNEL
151 
152 #include <sys/mutex.h>
153 
154 /* Defined in sljit_mod.c */
155 extern kmutex_t sljit_global_mutex;
156 
sljit_grab_lock(void)157 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_grab_lock(void)
158 {
159           mutex_enter(&sljit_global_mutex);
160 }
161 
sljit_release_lock(void)162 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_release_lock(void)
163 {
164           mutex_exit(&sljit_global_mutex);
165 }
166 #else
167 
168 #include <pthread.h>
169 
170 static pthread_mutex_t global_mutex = PTHREAD_MUTEX_INITIALIZER;
171 
sljit_grab_lock(void)172 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_grab_lock(void)
173 {
174           pthread_mutex_lock(&global_mutex);
175 }
176 
sljit_release_lock(void)177 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_release_lock(void)
178 {
179           pthread_mutex_unlock(&global_mutex);
180 }
181 #endif
182 
183 #endif /* SLJIT_UTIL_GLOBAL_LOCK */
184 
185 #endif /* _WIN32 */
186 
187 /* ------------------------------------------------------------------------ */
188 /*  Stack                                                                   */
189 /* ------------------------------------------------------------------------ */
190 
191 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK) || (defined SLJIT_EXECUTABLE_ALLOCATOR && SLJIT_EXECUTABLE_ALLOCATOR)
192 
193 #ifdef _KERNEL
194 #include <sys/param.h>
195 #include <uvm/uvm_extern.h>
196 #elif defined(_WIN32)
197 #include "windows.h"
198 #else
199 /* Provides mmap function. */
200 #include <sys/mman.h>
201 /* For detecting the page size. */
202 #include <unistd.h>
203 
204 #ifndef MAP_ANON
205 
206 #include <fcntl.h>
207 
208 /* Some old systems does not have MAP_ANON. */
209 static sljit_s32 dev_zero = -1;
210 
211 #if (defined SLJIT_SINGLE_THREADED && SLJIT_SINGLE_THREADED)
212 
open_dev_zero(void)213 static SLJIT_INLINE sljit_s32 open_dev_zero(void)
214 {
215           dev_zero = open("/dev/zero", O_RDWR);
216           return dev_zero < 0;
217 }
218 
219 #else /* SLJIT_SINGLE_THREADED */
220 
221 #include <pthread.h>
222 
223 static pthread_mutex_t dev_zero_mutex = PTHREAD_MUTEX_INITIALIZER;
224 
open_dev_zero(void)225 static SLJIT_INLINE sljit_s32 open_dev_zero(void)
226 {
227           pthread_mutex_lock(&dev_zero_mutex);
228           /* The dev_zero might be initialized by another thread during the waiting. */
229           if (dev_zero < 0) {
230                     dev_zero = open("/dev/zero", O_RDWR);
231           }
232           pthread_mutex_unlock(&dev_zero_mutex);
233           return dev_zero < 0;
234 }
235 
236 #endif /* SLJIT_SINGLE_THREADED */
237 
238 #endif
239 
240 #endif
241 
242 #endif /* SLJIT_UTIL_STACK || SLJIT_EXECUTABLE_ALLOCATOR */
243 
244 #if (defined SLJIT_UTIL_STACK && SLJIT_UTIL_STACK)
245 
246 /* Planning to make it even more clever in the future. */
247 static sljit_sw sljit_page_align = 0;
248 
sljit_allocate_stack(sljit_uw limit,sljit_uw max_limit,void * allocator_data)249 SLJIT_API_FUNC_ATTRIBUTE struct sljit_stack* SLJIT_CALL sljit_allocate_stack(sljit_uw limit, sljit_uw max_limit, void *allocator_data)
250 {
251           struct sljit_stack *stack;
252           void *ptr;
253 #ifdef _WIN32
254           SYSTEM_INFO si;
255 #endif
256 
257           SLJIT_UNUSED_ARG(allocator_data);
258           if (limit > max_limit || limit < 1)
259                     return NULL;
260 
261 #ifdef _WIN32
262           if (!sljit_page_align) {
263                     GetSystemInfo(&si);
264                     sljit_page_align = si.dwPageSize - 1;
265           }
266 #else
267           if (!sljit_page_align) {
268 #ifdef _KERNEL
269                     sljit_page_align = PAGE_SIZE;
270 #else
271                     sljit_page_align = sysconf(_SC_PAGESIZE);
272 #endif
273                     /* Should never happen. */
274                     if (sljit_page_align < 0)
275                               sljit_page_align = 4096;
276                     sljit_page_align--;
277           }
278 #endif
279 
280           stack = (struct sljit_stack*)SLJIT_MALLOC(sizeof(struct sljit_stack), allocator_data);
281           if (!stack)
282                     return NULL;
283 
284           /* Align max_limit. */
285           max_limit = (max_limit + sljit_page_align) & ~sljit_page_align;
286 
287 #ifdef _WIN32
288           ptr = VirtualAlloc(NULL, max_limit, MEM_RESERVE, PAGE_READWRITE);
289           if (!ptr) {
290                     SLJIT_FREE(stack, allocator_data);
291                     return NULL;
292           }
293           stack->max_limit = (sljit_u8 *)ptr;
294           stack->base = stack->max_limit + max_limit;
295           stack->limit = stack->base;
296           if (sljit_stack_resize(stack, stack->base - limit)) {
297                     sljit_free_stack(stack, allocator_data);
298                     return NULL;
299           }
300 #elif defined(_KERNEL)
301           ptr = (void *)uvm_km_alloc(kernel_map, max_limit, PAGE_SIZE, UVM_KMF_WIRED|UVM_KMF_ZERO);
302           if (ptr == NULL) {
303                     SLJIT_FREE(stack, allocator_data);
304                     return NULL;
305           }
306           stack->max_limit = (sljit_u8 *)ptr;
307           stack->base = stack->max_limit + max_limit;
308           stack->limit = stack->base - limit;
309 #else
310 #ifdef MAP_ANON
311           ptr = mmap(NULL, max_limit, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
312 #else
313           if (dev_zero < 0) {
314                     if (open_dev_zero()) {
315                               SLJIT_FREE(stack, allocator_data);
316                               return NULL;
317                     }
318           }
319           ptr = mmap(NULL, max_limit, PROT_READ | PROT_WRITE, MAP_PRIVATE, dev_zero, 0);
320 #endif
321           if (ptr == MAP_FAILED) {
322                     SLJIT_FREE(stack, allocator_data);
323                     return NULL;
324           }
325           stack->max_limit = (sljit_u8 *)ptr;
326           stack->base = stack->max_limit + max_limit;
327           stack->limit = stack->base - limit;
328 #endif
329           stack->top = stack->base;
330           return stack;
331 }
332 
333 #undef PAGE_ALIGN
334 
sljit_free_stack(struct sljit_stack * stack,void * allocator_data)335 SLJIT_API_FUNC_ATTRIBUTE void SLJIT_CALL sljit_free_stack(struct sljit_stack *stack, void *allocator_data)
336 {
337           SLJIT_UNUSED_ARG(allocator_data);
338 #ifdef _WIN32
339           VirtualFree((void*)stack->max_limit, 0, MEM_RELEASE);
340 #elif defined(_KERNEL)
341           uvm_km_free(kernel_map, (vaddr_t)stack->max_limit,
342               stack->base - stack->max_limit, UVM_KMF_WIRED);
343 #else
344           munmap((void*)stack->max_limit, stack->base - stack->max_limit);
345 #endif
346           SLJIT_FREE(stack, allocator_data);
347 }
348 
sljit_stack_resize(struct sljit_stack * stack,sljit_u8 * new_limit)349 SLJIT_API_FUNC_ATTRIBUTE sljit_sw SLJIT_CALL sljit_stack_resize(struct sljit_stack *stack, sljit_u8 *new_limit)
350 {
351 #if defined(MADV_DONTNEED) || defined(POSIX_MADV_DONTNEED)
352           sljit_uw aligned_old_limit;
353           sljit_uw aligned_new_limit;
354 #endif
355 
356           if ((new_limit < stack->max_limit) || (new_limit >= stack->base))
357                     return -1;
358 #ifdef _WIN32
359           aligned_new_limit = (sljit_uw)new_limit & ~sljit_page_align;
360           aligned_old_limit = ((sljit_uw)stack->limit) & ~sljit_page_align;
361           if (aligned_new_limit != aligned_old_limit) {
362                     if (aligned_new_limit < aligned_old_limit) {
363                               if (!VirtualAlloc((void*)aligned_new_limit, aligned_old_limit - aligned_new_limit, MEM_COMMIT, PAGE_READWRITE))
364                                         return -1;
365                     }
366                     else {
367                               if (!VirtualFree((void*)aligned_old_limit, aligned_new_limit - aligned_old_limit, MEM_DECOMMIT))
368                                         return -1;
369                     }
370           }
371           stack->limit = new_limit;
372           return 0;
373 #else
374           if (new_limit <= stack->limit) {
375                     stack->limit = new_limit;
376                     return 0;
377           }
378 #if defined(MADV_DONTNEED) || defined(POSIX_MADV_DONTNEED)
379           aligned_new_limit = (sljit_uw)new_limit & ~sljit_page_align;
380           aligned_old_limit = ((sljit_uw)stack->limit) & ~sljit_page_align;
381 #endif
382           /* If madvise is available, we release the unnecessary space. */
383 #if defined(MADV_DONTNEED)
384           if (aligned_new_limit > aligned_old_limit)
385                     madvise((void*)aligned_old_limit, aligned_new_limit - aligned_old_limit, MADV_DONTNEED);
386 #elif defined(POSIX_MADV_DONTNEED)
387           if (aligned_new_limit > aligned_old_limit)
388                     posix_madvise((void*)aligned_old_limit, aligned_new_limit - aligned_old_limit, POSIX_MADV_DONTNEED);
389 #endif
390           stack->limit = new_limit;
391           return 0;
392 #endif
393 }
394 
395 #endif /* SLJIT_UTIL_STACK */
396 
397 #endif
398