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 32
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 "movl " ENTRY_CURRENT_TABLE ", %eax\n\t" \
48 "testl %eax, %eax\n\t" \
49 "je 1f\n\t" \
50 "jmp *(4 * " slot ")(%eax)\n" \
51 "1:\n\t" \
52 "call " ENTRY_CURRENT_TABLE_GET "\n\t" \
53 "jmp *(4 * " slot ")(%eax)"
54
55 #define MAPI_TMP_STUB_ASM_GCC
56 #include "mapi_tmp.h"
57
58 #ifndef MAPI_MODE_BRIDGE
59
60 __asm__(".balign 32\n"
61 "x86_entry_end:");
62
63 #include <string.h>
64 #include "u_execmem.h"
65
66 extern const char x86_entry_start[] HIDDEN;
67 extern const char x86_entry_end[] HIDDEN;
68
69 void
entry_patch_public(void)70 entry_patch_public(void)
71 {
72 }
73
74 mapi_func
entry_get_public(int slot)75 entry_get_public(int slot)
76 {
77 return (mapi_func) (x86_entry_start + slot * X86_ENTRY_SIZE);
78 }
79
80 void
entry_patch(mapi_func entry,int slot)81 entry_patch(mapi_func entry, int slot)
82 {
83 char *code = (char *) entry;
84
85 *((unsigned long *) (code + 11)) = slot * sizeof(mapi_func);
86 *((unsigned long *) (code + 22)) = slot * sizeof(mapi_func);
87 }
88
89 mapi_func
entry_generate(int slot)90 entry_generate(int slot)
91 {
92 const char *code_templ = x86_entry_end - X86_ENTRY_SIZE;
93 void *code;
94 mapi_func entry;
95
96 code = u_execmem_alloc(X86_ENTRY_SIZE);
97 if (!code)
98 return NULL;
99
100 memcpy(code, code_templ, X86_ENTRY_SIZE);
101 entry = (mapi_func) code;
102 entry_patch(entry, slot);
103
104 return entry;
105 }
106
107 #endif /* MAPI_MODE_BRIDGE */
108