/* Copyright (C) 1995-2016 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library. If not, see <http://www.gnu.org/licenses/>. */ /* This is the canonical entry point, usually the first thing in the text segment. Note that the code in the .init section has already been run. This includes _init and _libc_init At this entry point, most registers' values are unspecified, except: x0 Contains a function pointer to be registered with `atexit'. This is how the dynamic linker arranges to have DT_FINI functions called for shared libraries that have been loaded before this code runs. sp The stack contains the arguments and environment: 0(sp) argc 8(sp) argv[0] ... (8*argc)(sp) NULL (8*(argc+1))(sp) envp[0] ... NULL */ .text .globl _start .type _start,#function _start: /* Create an initial frame with 0 LR and FP */ mov x29, #0 mov x30, #0 /* Setup _fini in argument register */ mov x5, x0 /* Load argc and a pointer to argv */ ldr x1, [sp, #0] add x2, sp, #8 /* Setup stack limit in argument register */ mov x6, sp #ifdef __PIC__ adrp x0, :got:main ldr x0, [x0, #:got_lo12:main] adrp x3, :got:_init ldr x3, [x3, #:got_lo12:_init] adrp x4, :got:_fini ldr x4, [x4, #:got_lo12:_fini] #else /* Set up the other arguments in registers */ ldr x0, =main ldr x3, =_init ldr x4, =_fini #endif /* Let the libc call main and exit with its return code. */ bl __uClibc_main /* should never get here....*/ bl abort /* Define a symbol for the first piece of initialized data. */ .data .globl __data_start __data_start: .long 0 .weak data_start data_start = __data_start