| /* |
| * Mesa 3-D graphics library |
| * |
| * Copyright (C) 2010 LunarG Inc. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included |
| * in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
| * DEALINGS IN THE SOFTWARE. |
| * |
| * Authors: |
| * Chia-I Wu <olv@lunarg.com> |
| */ |
| |
| #ifdef __CET__ |
| #define ENDBR "endbr32\n\t" |
| #else |
| #define ENDBR |
| #endif |
| |
| #ifdef HAVE_FUNC_ATTRIBUTE_VISIBILITY |
| #define HIDDEN __attribute__((visibility("hidden"))) |
| #else |
| #define HIDDEN |
| #endif |
| |
| #define X86_ENTRY_SIZE 64 |
| |
| __asm__(".text\n"); |
| |
| __asm__("x86_got:\n\t" |
| "call 1f\n" |
| "1:\n\t" |
| "popl %eax\n\t" |
| "addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %eax\n\t" |
| "ret"); |
| |
| __asm__(".balign 32\n" |
| "x86_entry_start:"); |
| |
| #define STUB_ASM_ENTRY(func) \ |
| ".globl " func "\n" \ |
| ".type " func ", @function\n" \ |
| ".balign 32\n" \ |
| func ":" |
| |
| #define LOC_BEGIN_SET_ECX |
| #define LOC_END_SET_ECX |
| #define LOC_END_JMP |
| |
| #define STUB_ASM_CODE(slot) \ |
| ENDBR \ |
| LOC_BEGIN_SET_ECX \ |
| "call 1f\n\t" \ |
| "1:\n\t" \ |
| "popl %ecx\n\t" \ |
| "addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %ecx\n\t" \ |
| LOC_END_SET_ECX \ |
| "movl " ENTRY_CURRENT_TABLE "@GOT(%ecx), %eax\n\t" \ |
| "mov (%eax), %eax\n\t" \ |
| "testl %eax, %eax\n\t" \ |
| "jne 1f\n\t" \ |
| "push %ebx\n\t" \ |
| "movl %ecx, %ebx\n\t" \ |
| "call " ENTRY_CURRENT_TABLE_GET "@PLT\n\t" \ |
| "popl %ebx\n\t" \ |
| "1:\n\t" \ |
| "jmp *(4 * " slot ")(%eax)\n\t" \ |
| LOC_END_JMP |
| |
| #define MAPI_TMP_STUB_ASM_GCC |
| #include "mapi_tmp.h" |
| |
| #ifndef MAPI_MODE_BRIDGE |
| |
| __asm__(".balign 32\n" |
| "x86_entry_end:"); |
| |
| #undef LOC_BEGIN_SET_ECX |
| #undef LOC_END_SET_ECX |
| #undef LOC_END_JMP |
| #define LOC_BEGIN_SET_ECX "jmp set_ecx\n\t" |
| #define LOC_END_SET_ECX "set_ecx:movl $0x12345678, %ecx\n\tloc_end_set_ecx:\n\t" |
| #define LOC_END_JMP "loc_end_jmp:" |
| |
| /* Any number big enough works. This is to make sure the final |
| * jmp is a long jmp */ |
| __asm__(STUB_ASM_CODE("10000")); |
| |
| extern const char loc_end_set_ecx[] HIDDEN; |
| extern const char loc_end_jmp[] HIDDEN; |
| |
| #include <string.h> |
| #include "u_execmem.h" |
| |
| extern unsigned long |
| x86_got(); |
| |
| extern const char x86_entry_start[] HIDDEN; |
| extern const char x86_entry_end[] HIDDEN; |
| |
| void |
| entry_patch_public(void) |
| { |
| } |
| |
| mapi_func |
| entry_get_public(int slot) |
| { |
| return (mapi_func) (x86_entry_start + slot * X86_ENTRY_SIZE); |
| } |
| |
| void |
| entry_patch(mapi_func entry, int slot) |
| { |
| char *code = (char *) entry; |
| int offset = loc_end_jmp - x86_entry_end - sizeof(unsigned long); |
| *((unsigned long *) (code + offset)) = slot * sizeof(mapi_func); |
| } |
| |
| mapi_func |
| entry_generate(int slot) |
| { |
| const char *code_templ = x86_entry_end; |
| char *code; |
| mapi_func entry; |
| |
| code = u_execmem_alloc(X86_ENTRY_SIZE); |
| if (!code) |
| return NULL; |
| |
| memcpy(code, code_templ, X86_ENTRY_SIZE); |
| entry = (mapi_func) code; |
| int ecx_value_off = loc_end_set_ecx - x86_entry_end - sizeof(unsigned long); |
| *((unsigned long *) (code + ecx_value_off)) = x86_got(); |
| |
| entry_patch(entry, slot); |
| |
| return entry; |
| } |
| |
| #endif /* MAPI_MODE_BRIDGE */ |