src/mapi/entry_x86_tsd.h

   1 /*
   2  * Mesa 3-D graphics library
   3  *
   4  * Copyright (C) 2010 LunarG Inc.
   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 OR
  17  * 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 OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  21  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  22  * DEALINGS IN THE SOFTWARE.
  23  *
  24  * Authors:
  25  *    Chia-I Wu <olv@lunarg.com>
  26  */
  27
  28 #ifdef HAVE_FUNC_ATTRIBUTE_VISIBILITY
  29 #define HIDDEN __attribute__((visibility("hidden")))
  30 #else
  31 #define HIDDEN
  32 #endif
  33
  34 #define X86_ENTRY_SIZE 64
  35
  36 __asm__(".text\n"
  37         ".balign 32\n"
  38         "x86_entry_start:");
  39
  40 #define STUB_ASM_ENTRY(func)        \
  41    ".globl " func "\n"              \
  42    ".type " func ", @function\n"    \
  43    ".balign 32\n"                   \
  44    func ":"
  45
  46 #define STUB_ASM_CODE(slot)         \
  47    "call 1f\n\t"                    \
  48    "1:\n\t"                         \
  49    "popl %ecx\n\t"                  \
  50    "addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx\n\t" \
  51    "movl " ENTRY_CURRENT_TABLE "@GOT(%ecx), %eax\n\t" \
  52    "mov (%eax), %eax\n\t"           \
  53    "testl %eax, %eax\n\t"           \
  54    "jne 1f\n\t"                     \
  55    "push %ebx\n\t"                  \
  56    "movl %ecx, %ebx\n\t"            \
  57    "call " ENTRY_CURRENT_TABLE_GET "@PLT\n\t" \
  58    "popl %ebx\n\t"                  \
  59    "1:\n\t"                         \
  60    "jmp *(4 * " slot ")(%eax)"
  61
  62 #define MAPI_TMP_STUB_ASM_GCC
  63 #include "mapi_tmp.h"
  64
  65 #ifndef MAPI_MODE_BRIDGE
  66
  67 __asm__(".balign 32\n"
  68         "x86_entry_end:");
  69
  70 #include <string.h>
  71 #include "u_execmem.h"
  72
  73 extern const char x86_entry_start[] HIDDEN;
  74 extern const char x86_entry_end[] HIDDEN;
  75
  76 void
  77 entry_patch_public(void)
  78 {
  79 }
  80
  81 mapi_func
  82 entry_get_public(int slot)
  83 {
  84    return (mapi_func) (x86_entry_start + slot * X86_ENTRY_SIZE);
  85 }
  86
  87 void
  88 entry_patch(mapi_func entry, int slot)
  89 {
  90    char *code = (char *) entry;
  91
  92    *((unsigned long *) (code + 11)) = slot * sizeof(mapi_func);
  93    *((unsigned long *) (code + 22)) = slot * sizeof(mapi_func);
  94 }
  95
  96 mapi_func
  97 entry_generate(int slot)
  98 {
  99    const char *code_templ = x86_entry_end - X86_ENTRY_SIZE;
 100    void *code;
 101    mapi_func entry;
 102
 103    code = u_execmem_alloc(X86_ENTRY_SIZE);
 104    if (!code)
 105       return NULL;
 106
 107    memcpy(code, code_templ, X86_ENTRY_SIZE);
 108    entry = (mapi_func) code;
 109    entry_patch(entry, slot);
 110
 111    return entry;
 112 }
 113
 114 #endif /* MAPI_MODE_BRIDGE */