1 /* Definitions of target machine for GNU compiler, for HPs running 2 HP-UX using the 64bit runtime model. 3 Copyright (C) 1999-2019 Free Software Foundation, Inc. 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 /* We use DTOR_LIST_BEGIN to carry a bunch of hacks to allow us to use 22 the init and fini array sections with both the HP and GNU linkers. 23 The linkers setup the required dynamic entries in the dynamic segment 24 and the dynamic linker does the calls. This approach avoids using 25 collect2. 26 27 The first hack is to implement __do_global_ctors_aux in crtbegin as 28 it needs to be the first entry in the init array so that it is called 29 last. HP got the order of the init array backwards. The DT_INIT_ARRAY 30 is supposed to be executed in the same order as the addresses appear in 31 the array. DT_FINI_ARRAY is supposed to be executed in the opposite 32 order. 33 34 The second hack is a set of plabels to implement the effect of 35 CRT_CALL_STATIC_FUNCTION. HP-UX 11 only supports DI_INIT_ARRAY and 36 DT_FINI_ARRAY and they put the arrays in .init and .fini, rather than 37 in .init_array and .fini_array. The standard defines for .init and 38 .fini have the execute flag set. So, the assembler has to be hacked 39 to munge the standard flags for these sections to make them agree 40 with what the HP linker expects. With the GNU linker, we need to 41 used the .init_array and .fini_array sections. So, we set up for 42 both just in case. Once we have built the table, the linker does 43 the rest of the work. 44 The order is significant. Placing __do_global_ctors_aux first in 45 the list, results in it being called last. User specified initializers, 46 either using the linker +init command or a plabel, run before the 47 initializers specified here. */ 48 49 /* We need to add frame_dummy to the initializer list if EH_FRAME_SECTION_NAME 50 is defined. */ 51 #if defined(__LIBGCC_EH_FRAME_SECTION_NAME__) 52 #define PA_INIT_FRAME_DUMMY_ASM_OP ".dword P%frame_dummy" 53 #else 54 #define PA_INIT_FRAME_DUMMY_ASM_OP "" 55 #endif 56 57 /* The following hack sets up the .init, .init_array, .fini and 58 .fini_array sections. */ 59 #define PA_CRTBEGIN_HACK \ 60 asm (TEXT_SECTION_ASM_OP); \ 61 static void __attribute__((used)) \ 62 __do_global_ctors_aux (void) \ 63 { \ 64 func_ptr *p = __CTOR_LIST__; \ 65 while (*(p + 1)) \ 66 p++; \ 67 for (; *p != (func_ptr) -1; p--) \ 68 (*p) (); \ 69 } \ 70 \ 71 asm (HP_INIT_ARRAY_SECTION_ASM_OP); \ 72 asm (".align 8"); \ 73 asm (".dword P%__do_global_ctors_aux"); \ 74 asm (PA_INIT_FRAME_DUMMY_ASM_OP); \ 75 asm (GNU_INIT_ARRAY_SECTION_ASM_OP); \ 76 asm (".align 8"); \ 77 asm (".dword P%__do_global_ctors_aux"); \ 78 asm (PA_INIT_FRAME_DUMMY_ASM_OP); \ 79 asm (HP_FINI_ARRAY_SECTION_ASM_OP); \ 80 asm (".align 8"); \ 81 asm (".dword P%__do_global_dtors_aux"); \ 82 asm (GNU_FINI_ARRAY_SECTION_ASM_OP); \ 83 asm (".align 8"); \ 84 asm (".dword P%__do_global_dtors_aux") 85 86 /* The following two variants of DTOR_LIST_BEGIN are identical to those 87 in crtstuff.c except for the addition of the above crtbegin hack. */ 88 #ifdef __LIBGCC_DTORS_SECTION_ASM_OP__ 89 #define DTOR_LIST_BEGIN \ 90 asm (DTORS_SECTION_ASM_OP); \ 91 STATIC func_ptr __DTOR_LIST__[1] \ 92 __attribute__ ((aligned(sizeof(func_ptr)))) \ 93 = { (func_ptr) (-1) }; \ 94 PA_CRTBEGIN_HACK 95 #else 96 #define DTOR_LIST_BEGIN \ 97 STATIC func_ptr __DTOR_LIST__[1] \ 98 __attribute__ ((section(".dtors"), aligned(sizeof(func_ptr)))) \ 99 = { (func_ptr) (-1) }; \ 100 PA_CRTBEGIN_HACK 101 #endif 102