1/* Special .init and .fini section support for IA64. 2 Copyright (C) 2000-2021 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 In addition to the permissions in the GNU Lesser General Public 11 License, the Free Software Foundation gives you unlimited 12 permission to link the compiled version of this file with other 13 programs, and to distribute those programs without any restriction 14 coming from the use of this file. (The GNU Lesser General Public 15 License restrictions do apply in other respects; for example, they 16 cover modification of the file, and distribution when not linked 17 into another program.) 18 19 Note that people who make modified versions of this file are not 20 obligated to grant this special exception for their modified 21 versions; it is their choice whether to do so. The GNU Lesser 22 General Public License gives permission to release a modified 23 version without this exception; this exception also makes it 24 possible to release a modified version which carries forward this 25 exception. 26 27 The GNU C Library is distributed in the hope that it will be useful, 28 but WITHOUT ANY WARRANTY; without even the implied warranty of 29 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 30 Lesser General Public License for more details. 31 32 You should have received a copy of the GNU Lesser General Public 33 License along with the GNU C Library. If not, see 34 <https://www.gnu.org/licenses/>. */ 35 36/* crti.S puts a function prologue at the beginning of the .init and 37 .fini sections and defines global symbols for those addresses, so 38 they can be called as functions. The symbols _init and _fini are 39 magic and cause the linker to emit DT_INIT and DT_FINI. */ 40 41#include <libc-symbols.h> 42#include <sysdep.h> 43#undef ret 44 45#ifndef PREINIT_FUNCTION 46# define PREINIT_FUNCTION __gmon_start__ 47#endif 48 49#ifndef PREINIT_FUNCTION_WEAK 50# define PREINIT_FUNCTION_WEAK 1 51#endif 52 53#if PREINIT_FUNCTION_WEAK 54 weak_extern (PREINIT_FUNCTION) 55#else 56 .hidden PREINIT_FUNCTION 57#endif 58 59/* If we have working .init_array support, we want to keep the .init 60 section empty (apart from the mandatory prologue/epilogue. This 61 ensures that the default unwind conventions (return-pointer in b0, 62 frame state in ar.pfs, etc.) will do the Right Thing. To ensure 63 an empty .init section, we register gmon_initializer() via the 64 .init_array. 65 66 --davidm 02/10/29 */ 67 68#if PREINIT_FUNCTION_WEAK 69/* This blob of assembly code is one simple C function: 70 71static void 72__attribute__ ((used)) 73gmon_initializer (void) 74{ 75 extern void weak_function __gmon_start__ (void); 76 77 if (__gmon_start__) 78 (*__gmon_start__)(); 79} 80 */ 81 .text 82 .align 64 83 .proc gmon_initializer# 84gmon_initializer: 85 .prologue 12, 32 86 .mmi 87 .save ar.pfs, r33 88 alloc r33 = ar.pfs, 0, 3, 0, 0 89 addl r14 = @ltoff(@fptr(PREINIT_FUNCTION#)), gp 90 .save rp, r32 91 mov r32 = b0 92 .mmi 93 mov r34 = r1 94 .body 95 ;; 96 ld8 r14 = [r14] 97 nop 0 98 ;; 99 .mib 100 cmp.eq p6, p7 = 0, r14 101 nop 0 102 (p6) br.cond.spnt .L1 103 ;; 104 .mib 105 nop 0 106 nop 0 107 br.call.sptk.many b0 = PREINIT_FUNCTION# 108 ;; 109 .mmi 110 mov r1 = r34 111 nop 0 112 nop 0 113.L1: 114 .mii 115 nop 0 116 mov ar.pfs = r33 117 nop 0 118 ;; 119 .mib 120 nop 0 121 mov b0 = r32 122 br.ret.sptk.many b0 123 .endp gmon_initializer# 124# undef PREINIT_FUNCTION 125# define PREINIT_FUNCTION gmon_initializer 126#endif 127 .section .init_array, "aw" 128 data8 @fptr(PREINIT_FUNCTION) 129 130 .section .init,"ax",@progbits 131 .global _init# 132 .hidden _init# 133 .proc _init# 134_init: 135 .prologue 136 .save ar.pfs, r34 137 alloc r34 = ar.pfs, 0, 3, 0, 0 138 .vframe r32 139 mov r32 = r12 140 .save rp, r33 141 mov r33 = b0 142 .body 143 adds r12 = -16, r12 144 ;; /* see gmon_initializer() above */ 145 .endp _init# 146 147 .section .fini,"ax",@progbits 148 .global _fini# 149 .hidden _fini# 150 .proc _fini# 151_fini: 152 .prologue 153 .save ar.pfs, r34 154 alloc r34 = ar.pfs, 0, 3, 0, 0 155 .vframe r32 156 mov r32 = r12 157 .save rp, r33 158 mov r33 = b0 159 .body 160 adds r12 = -16, r12 161 ;; 162 .endp _fini# 163