1 /* crtbegin object for windows32 targets. 2 Copyright (C) 2007-2013 Free Software Foundation, Inc. 3 4 Contributed by Danny Smith <dannysmith@users.sourceforge.net> 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify it under 9 the terms of the GNU General Public License as published by the Free 10 Software Foundation; either version 3, or (at your option) any later 11 version. 12 13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 14 WARRANTY; without even the implied warranty of MERCHANTABILITY or 15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 16 for more details. 17 18 Under Section 7 of GPL version 3, you are granted additional 19 permissions described in the GCC Runtime Library Exception, version 20 3.1, as published by the Free Software Foundation. 21 22 You should have received a copy of the GNU General Public License and 23 a copy of the GCC Runtime Library Exception along with this program; 24 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 25 <http://www.gnu.org/licenses/>. */ 26 27 /* Target machine header files require this define. */ 28 #define IN_LIBGCC2 29 30 #include "auto-host.h" 31 #include "tconfig.h" 32 #include "tsystem.h" 33 #include "coretypes.h" 34 #include "tm.h" 35 #include "libgcc_tm.h" 36 #include "unwind-dw2-fde.h" 37 38 #define WIN32_LEAN_AND_MEAN 39 #include <windows.h> 40 41 #ifndef LIBGCC_SONAME 42 #define LIBGCC_SONAME "libgcc_s.dll" 43 #endif 44 45 #ifndef LIBGCJ_SONAME 46 #define LIBGCJ_SONAME "libgcj_s.dll" 47 #endif 48 49 50 /* Make the declarations weak. This is critical for 51 _Jv_RegisterClasses because it lives in libgcj.a */ 52 extern void __register_frame_info (const void *, struct object *) 53 TARGET_ATTRIBUTE_WEAK; 54 extern void *__deregister_frame_info (const void *) 55 TARGET_ATTRIBUTE_WEAK; 56 extern void _Jv_RegisterClasses (const void *) TARGET_ATTRIBUTE_WEAK; 57 58 #if defined(HAVE_LD_RO_RW_SECTION_MIXING) 59 # define EH_FRAME_SECTION_CONST const 60 #else 61 # define EH_FRAME_SECTION_CONST 62 #endif 63 64 /* Stick a label at the beginning of the frame unwind info so we can 65 register/deregister it with the exception handling library code. */ 66 #if DWARF2_UNWIND_INFO 67 static EH_FRAME_SECTION_CONST char __EH_FRAME_BEGIN__[] 68 __attribute__((used, section(EH_FRAME_SECTION_NAME), aligned(4))) 69 = { }; 70 71 static struct object obj; 72 73 /* Handle of libgcc's DLL reference. */ 74 HANDLE hmod_libgcc; 75 #endif 76 77 #if TARGET_USE_JCR_SECTION 78 static void *__JCR_LIST__[] 79 __attribute__ ((used, section(JCR_SECTION_NAME), aligned(4))) 80 = { }; 81 #endif 82 83 /* Pull in references from libgcc.a(unwind-dw2-fde.o) in the 84 startfile. These are referenced by a ctor and dtor in crtend.o. */ 85 extern void __gcc_register_frame (void); 86 extern void __gcc_deregister_frame (void); 87 88 void 89 __gcc_register_frame (void) 90 { 91 #if DWARF2_UNWIND_INFO 92 /* Weak undefined symbols won't be pulled in from dlls; hence 93 we first test if the dll is already loaded and, if so, 94 get the symbol's address at run-time. If the dll is not loaded, 95 fallback to weak linkage to static archive. */ 96 97 void (*register_frame_fn) (const void *, struct object *); 98 HANDLE h = GetModuleHandle (LIBGCC_SONAME); 99 100 if (h) 101 { 102 /* Increasing the load-count of LIBGCC_SONAME DLL. */ 103 hmod_libgcc = LoadLibrary (LIBGCC_SONAME); 104 register_frame_fn = (void (*) (const void *, struct object *)) 105 GetProcAddress (h, "__register_frame_info"); 106 } 107 else 108 register_frame_fn = __register_frame_info; 109 if (register_frame_fn) 110 register_frame_fn (__EH_FRAME_BEGIN__, &obj); 111 #endif 112 113 #if TARGET_USE_JCR_SECTION 114 if (__JCR_LIST__[0]) 115 { 116 void (*register_class_fn) (const void *); 117 HANDLE h = GetModuleHandle (LIBGCJ_SONAME); 118 if (h) 119 register_class_fn = (void (*) (const void *)) 120 GetProcAddress (h, "_Jv_RegisterClasses"); 121 else 122 register_class_fn = _Jv_RegisterClasses; 123 124 if (register_class_fn) 125 register_class_fn (__JCR_LIST__); 126 } 127 #endif 128 } 129 130 void 131 __gcc_deregister_frame (void) 132 { 133 #if DWARF2_UNWIND_INFO 134 void * (*deregister_frame_fn) (const void *); 135 HANDLE h = GetModuleHandle (LIBGCC_SONAME); 136 if (h) 137 deregister_frame_fn = (void* (*) (const void *)) 138 GetProcAddress (h, "__deregister_frame_info"); 139 else 140 deregister_frame_fn = __deregister_frame_info; 141 if (deregister_frame_fn) 142 deregister_frame_fn (__EH_FRAME_BEGIN__); 143 if (hmod_libgcc) 144 FreeLibrary (hmod_libgcc); 145 #endif 146 } 147