src/mapi/glapi/glapi_entrypoint.c

   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 "c11/threads.h"
  33 #include "glapi/glapi_priv.h"
  34 #include "u_execmem.h"
  35
  36
  37 #ifdef USE_X86_ASM
  38
  39 #if defined( GLX_USE_TLS )
  40 extern       GLubyte gl_dispatch_functions_start[];
  41 extern       GLubyte gl_dispatch_functions_end[];
  42 #else
  43 extern const GLubyte gl_dispatch_functions_start[];
  44 #endif
  45
  46 #endif /* USE_X86_ASM */
  47
  48
  49 #if defined(DISPATCH_FUNCTION_SIZE)
  50
  51 _glapi_proc
  52 get_entrypoint_address(unsigned int functionOffset)
  53 {
  54    return (_glapi_proc) (gl_dispatch_functions_start
  55                          + (DISPATCH_FUNCTION_SIZE * functionOffset));
  56 }
  57
  58 #endif
  59
  60
  61 #if defined(USE_X86_ASM)
  62
  63 /**
  64  * Perform platform-specific GL API entry-point fixups.
  65  */
  66 static void
  67 init_glapi_relocs( void )
  68 {
  69 #if defined(GLX_USE_TLS) && !defined(GLX_X86_READONLY_TEXT)
  70     extern unsigned long _x86_get_dispatch(void);
  71     char run_time_patch[] = {
  72        0x65, 0xa1, 0, 0, 0, 0 /* movl %gs:0,%eax */
  73     };
  74     GLuint *offset = (GLuint *) &run_time_patch[2]; /* 32-bits for x86/32 */
  75     const GLubyte * const get_disp = (const GLubyte *) run_time_patch;
  76     GLubyte * curr_func = (GLubyte *) gl_dispatch_functions_start;
  77
  78     *offset = _x86_get_dispatch();
  79     while ( curr_func != (GLubyte *) gl_dispatch_functions_end ) {
  80         (void) memcpy( curr_func, get_disp, sizeof(run_time_patch));
  81         curr_func += DISPATCH_FUNCTION_SIZE;
  82     }
  83 #endif
  84 }
  85
  86
  87 /**
  88  * Generate a dispatch function (entrypoint) which jumps through
  89  * the given slot number (offset) in the current dispatch table.
  90  * We need assembly language in order to accomplish this.
  91  */
  92 _glapi_proc
  93 generate_entrypoint(unsigned int functionOffset)
  94 {
  95    /* 32 is chosen as something of a magic offset.  For x86, the dispatch
  96     * at offset 32 is the first one where the offset in the
  97     * "jmp OFFSET*4(%eax)" can't be encoded in a single byte.
  98     */
  99    const GLubyte * const template_func = gl_dispatch_functions_start
 100      + (DISPATCH_FUNCTION_SIZE * 32);
 101    GLubyte * const code = (GLubyte *) u_execmem_alloc(DISPATCH_FUNCTION_SIZE);
 102
 103
 104    if ( code != NULL ) {
 105       (void) memcpy(code, template_func, DISPATCH_FUNCTION_SIZE);
 106       fill_in_entrypoint_offset( (_glapi_proc) code, functionOffset );
 107    }
 108
 109    return (_glapi_proc) code;
 110 }
 111
 112
 113 /**
 114  * This function inserts a new dispatch offset into the assembly language
 115  * stub that was generated with the preceeding function.
 116  */
 117 void
 118 fill_in_entrypoint_offset(_glapi_proc entrypoint, unsigned int offset)
 119 {
 120    GLubyte * const code = (GLubyte *) entrypoint;
 121
 122 #if defined(GLX_USE_TLS)
 123    *((unsigned int *)(code +  8)) = 4 * offset;
 124 #else
 125    *((unsigned int *)(code + 11)) = 4 * offset;
 126    *((unsigned int *)(code + 22)) = 4 * offset;
 127 #endif
 128 }
 129
 130
 131 #elif defined(USE_SPARC_ASM)
 132
 133 extern void __glapi_sparc_icache_flush(unsigned int *);
 134
 135 static void
 136 init_glapi_relocs( void )
 137 {
 138 #if defined(HAVE_PTHREAD) || defined(GLX_USE_TLS)
 139     static const unsigned int template[] = {
 140 #ifdef GLX_USE_TLS
 141         0x05000000, /* sethi %hi(_glapi_tls_Dispatch), %g2 */
 142         0x8730e00a, /* srl %g3, 10, %g3 */
 143         0x8410a000, /* or %g2, %lo(_glapi_tls_Dispatch), %g2 */
 144 #ifdef __arch64__
 145         0xc259c002, /* ldx [%g7 + %g2], %g1 */
 146         0xc2584003, /* ldx [%g1 + %g3], %g1 */
 147 #else
 148         0xc201c002, /* ld [%g7 + %g2], %g1 */
 149         0xc2004003, /* ld [%g1 + %g3], %g1 */
 150 #endif
 151         0x81c04000, /* jmp %g1 */
 152         0x01000000, /* nop  */
 153 #else
 154 #ifdef __arch64__
 155         0x03000000, /* 64-bit 0x00 --> sethi %hh(_glapi_Dispatch), %g1 */
 156         0x05000000, /* 64-bit 0x04 --> sethi %lm(_glapi_Dispatch), %g2 */
 157         0x82106000, /* 64-bit 0x08 --> or %g1, %hm(_glapi_Dispatch), %g1 */
 158         0x8730e00a, /* 64-bit 0x0c --> srl %g3, 10, %g3 */
 159         0x83287020, /* 64-bit 0x10 --> sllx %g1, 32, %g1 */
 160         0x82004002, /* 64-bit 0x14 --> add %g1, %g2, %g1 */
 161         0xc2586000, /* 64-bit 0x18 --> ldx [%g1 + %lo(_glapi_Dispatch)], %g1 */
 162 #else
 163         0x03000000, /* 32-bit 0x00 --> sethi %hi(_glapi_Dispatch), %g1 */
 164         0x8730e00a, /* 32-bit 0x04 --> srl %g3, 10, %g3 */
 165         0xc2006000, /* 32-bit 0x08 --> ld [%g1 + %lo(_glapi_Dispatch)], %g1 */
 166 #endif
 167         0x80a06000, /*             --> cmp %g1, 0 */
 168         0x02800005, /*             --> be +4*5 */
 169         0x01000000, /*             -->  nop  */
 170 #ifdef __arch64__
 171         0xc2584003, /* 64-bit      --> ldx [%g1 + %g3], %g1 */
 172 #else
 173         0xc2004003, /* 32-bit      --> ld [%g1 + %g3], %g1 */
 174 #endif
 175         0x81c04000, /*             --> jmp %g1 */
 176         0x01000000, /*             --> nop  */
 177 #ifdef __arch64__
 178         0x9de3bf80, /* 64-bit      --> save  %sp, -128, %sp */
 179 #else
 180         0x9de3bfc0, /* 32-bit      --> save  %sp, -64, %sp */
 181 #endif
 182         0xa0100003, /*             --> mov  %g3, %l0 */
 183         0x40000000, /*             --> call _glapi_get_dispatch */
 184         0x01000000, /*             -->  nop */
 185         0x82100008, /*             --> mov %o0, %g1 */
 186         0x86100010, /*             --> mov %l0, %g3 */
 187         0x10bffff7, /*             --> ba -4*9 */
 188         0x81e80000, /*             -->  restore  */
 189 #endif
 190     };
 191 #ifdef GLX_USE_TLS
 192     extern unsigned int __glapi_sparc_tls_stub;
 193     extern unsigned long __glapi_sparc_get_dispatch(void);
 194     unsigned int *code = &__glapi_sparc_tls_stub;
 195     unsigned long dispatch = __glapi_sparc_get_dispatch();
 196 #else
 197     extern unsigned int __glapi_sparc_pthread_stub;
 198     unsigned int *code = &__glapi_sparc_pthread_stub;
 199     unsigned long dispatch = (unsigned long) &_glapi_Dispatch;
 200     unsigned long call_dest = (unsigned long ) &_glapi_get_dispatch;
 201     int idx;
 202 #endif
 203
 204 #ifdef GLX_USE_TLS
 205     code[0] = template[0] | (dispatch >> 10);
 206     code[1] = template[1];
 207     __glapi_sparc_icache_flush(&code[0]);
 208     code[2] = template[2] | (dispatch & 0x3ff);
 209     code[3] = template[3];
 210     __glapi_sparc_icache_flush(&code[2]);
 211     code[4] = template[4];
 212     code[5] = template[5];
 213     __glapi_sparc_icache_flush(&code[4]);
 214     code[6] = template[6];
 215     __glapi_sparc_icache_flush(&code[6]);
 216 #else
 217 #if defined(__arch64__)
 218     code[0] = template[0] | (dispatch >> (32 + 10));
 219     code[1] = template[1] | ((dispatch & 0xffffffff) >> 10);
 220     __glapi_sparc_icache_flush(&code[0]);
 221     code[2] = template[2] | ((dispatch >> 32) & 0x3ff);
 222     code[3] = template[3];
 223     __glapi_sparc_icache_flush(&code[2]);
 224     code[4] = template[4];
 225     code[5] = template[5];
 226     __glapi_sparc_icache_flush(&code[4]);
 227     code[6] = template[6] | (dispatch & 0x3ff);
 228     idx = 7;
 229 #else
 230     code[0] = template[0] | (dispatch >> 10);
 231     code[1] = template[1];
 232     __glapi_sparc_icache_flush(&code[0]);
 233     code[2] = template[2] | (dispatch & 0x3ff);
 234     idx = 3;
 235 #endif
 236     code[idx + 0] = template[idx + 0];
 237     __glapi_sparc_icache_flush(&code[idx - 1]);
 238     code[idx + 1] = template[idx + 1];
 239     code[idx + 2] = template[idx + 2];
 240     __glapi_sparc_icache_flush(&code[idx + 1]);
 241     code[idx + 3] = template[idx + 3];
 242     code[idx + 4] = template[idx + 4];
 243     __glapi_sparc_icache_flush(&code[idx + 3]);
 244     code[idx + 5] = template[idx + 5];
 245     code[idx + 6] = template[idx + 6];
 246     __glapi_sparc_icache_flush(&code[idx + 5]);
 247     code[idx + 7] = template[idx + 7];
 248     code[idx + 8] = template[idx + 8] |
 249             (((call_dest - ((unsigned long) &code[idx + 8]))
 250               >> 2) & 0x3fffffff);
 251     __glapi_sparc_icache_flush(&code[idx + 7]);
 252     code[idx + 9] = template[idx + 9];
 253     code[idx + 10] = template[idx + 10];
 254     __glapi_sparc_icache_flush(&code[idx + 9]);
 255     code[idx + 11] = template[idx + 11];
 256     code[idx + 12] = template[idx + 12];
 257     __glapi_sparc_icache_flush(&code[idx + 11]);
 258     code[idx + 13] = template[idx + 13];
 259     __glapi_sparc_icache_flush(&code[idx + 13]);
 260 #endif
 261 #endif
 262 }
 263
 264
 265 _glapi_proc
 266 generate_entrypoint(GLuint functionOffset)
 267 {
 268 #if defined(HAVE_PTHREAD) || defined(GLX_USE_TLS)
 269    static const unsigned int template[] = {
 270       0x07000000, /* sethi %hi(0), %g3 */
 271       0x8210000f, /* mov  %o7, %g1 */
 272       0x40000000, /* call */
 273       0x9e100001, /* mov  %g1, %o7 */
 274    };
 275 #ifdef GLX_USE_TLS
 276    extern unsigned int __glapi_sparc_tls_stub;
 277    unsigned long call_dest = (unsigned long ) &__glapi_sparc_tls_stub;
 278 #else
 279    extern unsigned int __glapi_sparc_pthread_stub;
 280    unsigned long call_dest = (unsigned long ) &__glapi_sparc_pthread_stub;
 281 #endif
 282    unsigned int *code = (unsigned int *) u_execmem_alloc(sizeof(template));
 283    if (code) {
 284       code[0] = template[0] | (functionOffset & 0x3fffff);
 285       code[1] = template[1];
 286       __glapi_sparc_icache_flush(&code[0]);
 287       code[2] = template[2] |
 288          (((call_dest - ((unsigned long) &code[2]))
 289            >> 2) & 0x3fffffff);
 290       code[3] = template[3];
 291       __glapi_sparc_icache_flush(&code[2]);
 292    }
 293    return (_glapi_proc) code;
 294 #endif
 295 }
 296
 297
 298 void
 299 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
 300 {
 301    unsigned int *code = (unsigned int *) entrypoint;
 302
 303    code[0] &= ~0x3fffff;
 304    code[0] |= (offset * sizeof(void *)) & 0x3fffff;
 305    __glapi_sparc_icache_flush(&code[0]);
 306 }
 307
 308
 309 #else /* USE_*_ASM */
 310
 311 static void
 312 init_glapi_relocs( void )
 313 {
 314 }
 315
 316
 317 _glapi_proc
 318 generate_entrypoint(GLuint functionOffset)
 319 {
 320    (void) functionOffset;
 321    return NULL;
 322 }
 323
 324
 325 void
 326 fill_in_entrypoint_offset(_glapi_proc entrypoint, GLuint offset)
 327 {
 328    /* an unimplemented architecture */
 329    (void) entrypoint;
 330    (void) offset;
 331 }
 332
 333 #endif /* USE_*_ASM */
 334
 335
 336 void
 337 init_glapi_relocs_once( void )
 338 {
 339 #if defined(HAVE_PTHREAD) || defined(GLX_USE_TLS)
 340    static once_flag flag = ONCE_FLAG_INIT;
 341    call_once(&flag, init_glapi_relocs);
 342 #endif
 343 }