1 /*
2 * Mesa 3-D graphics library
3 *
4 * Copyright (C) 1999-2008 Brian Paul All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 /**
26 * \file glapi_entrypoint.c
27 *
28 * Arch-specific code for manipulating GL API entrypoints (dispatch stubs).
29 */
30
31
32 #include <string.h>
33
34 #include "c11/threads.h"
35 #include "glapi/glapi_priv.h"
36 #include "u_execmem.h"
37
38
39 #ifdef USE_X86_ASM
40
41 #if defined( USE_ELF_TLS )
42 extern GLubyte gl_dispatch_functions_start[];
43 extern GLubyte gl_dispatch_functions_end[];
44 #else
45 extern const GLubyte gl_dispatch_functions_start[];
46 #endif
47
48 #endif /* USE_X86_ASM */
49
50
51 #if defined(DISPATCH_FUNCTION_SIZE)
52
53 _glapi_proc
get_entrypoint_address(unsigned int functionOffset)54 get_entrypoint_address(unsigned int functionOffset)
55 {
56 return (_glapi_proc) (gl_dispatch_functions_start
57 + (DISPATCH_FUNCTION_SIZE * functionOffset));
58 }
59
60 #endif
61
62
63 #if defined(USE_X86_ASM)
64
65 /**
66 * Perform platform-specific GL API entry-point fixups.
67 */
68 static void
init_glapi_relocs(void)69 init_glapi_relocs( void )
70 {
71 #if defined(USE_ELF_TLS) && !defined(GLX_X86_READONLY_TEXT)
72 extern unsigned long _x86_get_dispatch(void);
73 char run_time_patch[] = {
74 0x65, 0xa1, 0, 0, 0, 0 /* movl %gs:0,%eax */
75 };
76 GLuint *offset = (GLuint *) &run_time_patch[2]; /* 32-bits for x86/32 */
77 const GLubyte * const get_disp = (const GLubyte *) run_time_patch;
78 GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
79
80 *offset = _x86_get_dispatch();
81 while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
82 (void) memcpy( curr_func, get_disp, sizeof(run_time_patch));
83 curr_func += DISPATCH_FUNCTION_SIZE;
84 }
85 #endif
86 }
87
88
89 /**
90 * Generate a dispatch function (entrypoint) which jumps through
91 * the given slot number (offset) in the current dispatch table.
92 * We need assembly language in order to accomplish this.
93 */
94 _glapi_proc
generate_entrypoint(unsigned int functionOffset)95 generate_entrypoint(unsigned int functionOffset)
96 {
97 /* 32 is chosen as something of a magic offset. For x86, the dispatch
98 * at offset 32 is the first one where the offset in the
99 * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
100 */
101 const GLubyte * const template_func = gl_dispatch_functions_start
102 + (DISPATCH_FUNCTION_SIZE * 32);
103 GLubyte * const code = (GLubyte *) u_execmem_alloc(DISPATCH_FUNCTION_SIZE);
104
105
106 if ( code != NULL ) {
107 (void) memcpy(code, template_func, DISPATCH_FUNCTION_SIZE);
108 fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
109 }
110
111 return (_glapi_proc) code;
112 }
113
114
115 /**
116 * This function inserts a new dispatch offset into the assembly language
117 * stub that was generated with the preceeding function.
118 */
119 void
fill_in_entrypoint_offset(_glapi_proc entrypoint,unsigned int offset)120 fill_in_entrypoint_offset(_glapi_proc entrypoint, unsigned int offset)
121 {
122 GLubyte * const code = (GLubyte *) entrypoint;
123
124 #if defined(USE_ELF_TLS)
125 *((unsigned int *)(code + 8)) = 4 * offset;
126 #else
127 *((unsigned int *)(code + 11)) = 4 * offset;
128 *((unsigned int *)(code + 22)) = 4 * offset;
129 #endif
130 }
131
132
133 #elif defined(USE_SPARC_ASM)
134
135 extern void __glapi_sparc_icache_flush(unsigned int *);
136
137 static void
init_glapi_relocs(void)138 init_glapi_relocs( void )
139 {
140 #if defined(HAVE_PTHREAD) || defined(USE_ELF_TLS)
141 static const unsigned int template[] = {
142 #ifdef USE_ELF_TLS
143 0x05000000, /* sethi %hi(_glapi_tls_Dispatch), %g2 */
144 0x8730e00a, /* srl %g3, 10, %g3 */
145 0x8410a000, /* or %g2, %lo(_glapi_tls_Dispatch), %g2 */
146 #ifdef __arch64__
147 0xc259c002, /* ldx [%g7 + %g2], %g1 */
148 0xc2584003, /* ldx [%g1 + %g3], %g1 */
149 #else
150 0xc201c002, /* ld [%g7 + %g2], %g1 */
151 0xc2004003, /* ld [%g1 + %g3], %g1 */
152 #endif
153 0x81c04000, /* jmp %g1 */
154 0x01000000, /* nop */
155 #else
156 #ifdef __arch64__
157 0x03000000, /* 64-bit 0x00 --> sethi %hh(_glapi_Dispatch), %g1 */
158 0x05000000, /* 64-bit 0x04 --> sethi %lm(_glapi_Dispatch), %g2 */
159 0x82106000, /* 64-bit 0x08 --> or %g1, %hm(_glapi_Dispatch), %g1 */
160 0x8730e00a, /* 64-bit 0x0c --> srl %g3, 10, %g3 */
161 0x83287020, /* 64-bit 0x10 --> sllx %g1, 32, %g1 */
162 0x82004002, /* 64-bit 0x14 --> add %g1, %g2, %g1 */
163 0xc2586000, /* 64-bit 0x18 --> ldx [%g1 + %lo(_glapi_Dispatch)], %g1 */
164 #else
165 0x03000000, /* 32-bit 0x00 --> sethi %hi(_glapi_Dispatch), %g1 */
166 0x8730e00a, /* 32-bit 0x04 --> srl %g3, 10, %g3 */
167 0xc2006000, /* 32-bit 0x08 --> ld [%g1 + %lo(_glapi_Dispatch)], %g1 */
168 #endif
169 0x80a06000, /* --> cmp %g1, 0 */
170 0x02800005, /* --> be +4*5 */
171 0x01000000, /* --> nop */
172 #ifdef __arch64__
173 0xc2584003, /* 64-bit --> ldx [%g1 + %g3], %g1 */
174 #else
175 0xc2004003, /* 32-bit --> ld [%g1 + %g3], %g1 */
176 #endif
177 0x81c04000, /* --> jmp %g1 */
178 0x01000000, /* --> nop */
179 #ifdef __arch64__
180 0x9de3bf80, /* 64-bit --> save %sp, -128, %sp */
181 #else
182 0x9de3bfc0, /* 32-bit --> save %sp, -64, %sp */
183 #endif
184 0xa0100003, /* --> mov %g3, %l0 */
185 0x40000000, /* --> call _glapi_get_dispatch */
186 0x01000000, /* --> nop */
187 0x82100008, /* --> mov %o0, %g1 */
188 0x86100010, /* --> mov %l0, %g3 */
189 0x10bffff7, /* --> ba -4*9 */
190 0x81e80000, /* --> restore */
191 #endif
192 };
193 #ifdef USE_ELF_TLS
194 extern unsigned int __glapi_sparc_tls_stub;
195 extern unsigned long __glapi_sparc_get_dispatch(void);
196 unsigned int *code = &__glapi_sparc_tls_stub;
197 unsigned long dispatch = __glapi_sparc_get_dispatch();
198 #else
199 extern unsigned int __glapi_sparc_pthread_stub;
200 unsigned int *code = &__glapi_sparc_pthread_stub;
201 unsigned long dispatch = (unsigned long) &_glapi_Dispatch;
202 unsigned long call_dest = (unsigned long ) &_glapi_get_dispatch;
203 int idx;
204 #endif
205
206 #ifdef USE_ELF_TLS
207 code[0] = template[0] | (dispatch >> 10);
208 code[1] = template[1];
209 __glapi_sparc_icache_flush(&code[0]);
210 code[2] = template[2] | (dispatch & 0x3ff);
211 code[3] = template[3];
212 __glapi_sparc_icache_flush(&code[2]);
213 code[4] = template[4];
214 code[5] = template[5];
215 __glapi_sparc_icache_flush(&code[4]);
216 code[6] = template[6];
217 __glapi_sparc_icache_flush(&code[6]);
218 #else
219 #if defined(__arch64__)
220 code[0] = template[0] | (dispatch >> (32 + 10));
221 code[1] = template[1] | ((dispatch & 0xffffffff) >> 10);
222 __glapi_sparc_icache_flush(&code[0]);
223 code[2] = template[2] | ((dispatch >> 32) & 0x3ff);
224 code[3] = template[3];
225 __glapi_sparc_icache_flush(&code[2]);
226 code[4] = template[4];
227 code[5] = template[5];
228 __glapi_sparc_icache_flush(&code[4]);
229 code[6] = template[6] | (dispatch & 0x3ff);
230 idx = 7;
231 #else
232 code[0] = template[0] | (dispatch >> 10);
233 code[1] = template[1];
234 __glapi_sparc_icache_flush(&code[0]);
235 code[2] = template[2] | (dispatch & 0x3ff);
236 idx = 3;
237 #endif
238 code[idx + 0] = template[idx + 0];
239 __glapi_sparc_icache_flush(&code[idx - 1]);
240 code[idx + 1] = template[idx + 1];
241 code[idx + 2] = template[idx + 2];
242 __glapi_sparc_icache_flush(&code[idx + 1]);
243 code[idx + 3] = template[idx + 3];
244 code[idx + 4] = template[idx + 4];
245 __glapi_sparc_icache_flush(&code[idx + 3]);
246 code[idx + 5] = template[idx + 5];
247 code[idx + 6] = template[idx + 6];
248 __glapi_sparc_icache_flush(&code[idx + 5]);
249 code[idx + 7] = template[idx + 7];
250 code[idx + 8] = template[idx + 8] |
251 (((call_dest - ((unsigned long) &code[idx + 8]))
252 >> 2) & 0x3fffffff);
253 __glapi_sparc_icache_flush(&code[idx + 7]);
254 code[idx + 9] = template[idx + 9];
255 code[idx + 10] = template[idx + 10];
256 __glapi_sparc_icache_flush(&code[idx + 9]);
257 code[idx + 11] = template[idx + 11];
258 code[idx + 12] = template[idx + 12];
259 __glapi_sparc_icache_flush(&code[idx + 11]);
260 code[idx + 13] = template[idx + 13];
261 __glapi_sparc_icache_flush(&code[idx + 13]);
262 #endif
263 #endif
264 }
265
266
267 _glapi_proc
generate_entrypoint(GLuint functionOffset)268 generate_entrypoint(GLuint functionOffset)
269 {
270 #if defined(HAVE_PTHREAD) || defined(USE_ELF_TLS)
271 static const unsigned int template[] = {
272 0x07000000, /* sethi %hi(0), %g3 */
273 0x8210000f, /* mov %o7, %g1 */
274 0x40000000, /* call */
275 0x9e100001, /* mov %g1, %o7 */
276 };
277 #ifdef USE_ELF_TLS
278 extern unsigned int __glapi_sparc_tls_stub;
279 unsigned long call_dest = (unsigned long ) &__glapi_sparc_tls_stub;
280 #else
281 extern unsigned int __glapi_sparc_pthread_stub;
282 unsigned long call_dest = (unsigned long ) &__glapi_sparc_pthread_stub;
283 #endif
284 unsigned int *code = (unsigned int *) u_execmem_alloc(sizeof(template));
285 if (code) {
286 code[0] = template[0] | (functionOffset & 0x3fffff);
287 code[1] = template[1];
288 __glapi_sparc_icache_flush(&code[0]);
289 code[2] = template[2] |
290 (((call_dest - ((unsigned long) &code[2]))
291 >> 2) & 0x3fffffff);
292 code[3] = template[3];
293 __glapi_sparc_icache_flush(&code[2]);
294 }
295 return (_glapi_proc) code;
296 #endif
297 }
298
299
300 void
fill_in_entrypoint_offset(_glapi_proc entrypoint,GLuint offset)301 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
302 {
303 unsigned int *code = (unsigned int *) entrypoint;
304
305 code[0] &= ~0x3fffff;
306 code[0] |= (offset * sizeof(void *)) & 0x3fffff;
307 __glapi_sparc_icache_flush(&code[0]);
308 }
309
310
311 #else /* USE_*_ASM */
312
313 #if defined(HAVE_PTHREAD) || defined(USE_ELF_TLS)
314 static void
init_glapi_relocs(void)315 init_glapi_relocs( void )
316 {
317 }
318 #endif
319
320
321 _glapi_proc
generate_entrypoint(GLuint functionOffset)322 generate_entrypoint(GLuint functionOffset)
323 {
324 (void) functionOffset;
325 return NULL;
326 }
327
328
329 void
fill_in_entrypoint_offset(_glapi_proc entrypoint,GLuint offset)330 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
331 {
332 /* an unimplemented architecture */
333 (void) entrypoint;
334 (void) offset;
335 }
336
337 #endif /* USE_*_ASM */
338
339
340 void
init_glapi_relocs_once(void)341 init_glapi_relocs_once( void )
342 {
343 #if defined(HAVE_PTHREAD) || defined(USE_ELF_TLS)
344 static once_flag flag = ONCE_FLAG_INIT;
345 call_once(&flag, init_glapi_relocs);
346 #endif
347 }
348