1/* Special .init and .fini section support for Alpha. 2 Copyright (C) 2001-2022 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 This differs from what would be generated for ordinary code in that 42 we save and restore the GP within the function. In order for linker 43 relaxation to work, the value in the GP register on exit from a function 44 must be valid for the function entry point. Normally, a function is 45 contained within one object file and this is not an issue, provided 46 that the function reloads the gp after making any function calls. 47 However, _init and _fini are constructed from pieces of many object 48 files, all of which may have different GP values. So we must reload 49 the GP value from crti.o in crtn.o. */ 50 51#include <libc-symbols.h> 52#include <sysdep.h> 53 54#ifndef PREINIT_FUNCTION 55# define PREINIT_FUNCTION __gmon_start__ 56#endif 57 58#ifndef PREINIT_FUNCTION_WEAK 59# define PREINIT_FUNCTION_WEAK 1 60#endif 61 62#if PREINIT_FUNCTION_WEAK 63 weak_extern (PREINIT_FUNCTION) 64#else 65 .hidden PREINIT_FUNCTION 66#endif 67 68 .section .init, "ax", @progbits 69 .globl _init 70 .hidden _init 71 .type _init, @function 72 .usepv _init, std 73_init: 74 ldgp $29, 0($27) 75 subq $30, 16, $30 76#if PREINIT_FUNCTION_WEAK 77 lda $27, PREINIT_FUNCTION 78#endif 79 stq $26, 0($30) 80 stq $29, 8($30) 81#if PREINIT_FUNCTION_WEAK 82 beq $27, 1f 83 jsr $26, ($27), PREINIT_FUNCTION 84 ldq $29, 8($30) 851: 86#else 87 bsr $26, PREINIT_FUNCTION !samegp 88#endif 89 .p2align 3 90 91 .section .fini, "ax", @progbits 92 .globl _fini 93 .hidden _fini 94 .type _fini,@function 95 .usepv _fini,std 96_fini: 97 ldgp $29, 0($27) 98 subq $30, 16, $30 99 stq $26, 0($30) 100 stq $29, 8($30) 101 .p2align 3 102