gcc/libgcc/config/arm/crtn.S

84 lines
2.5 KiB
ArmAsm

# Copyright (C) 2001, 2004, 2008, 2009, 2010, 2011, 2012
# Free Software Foundation, Inc.
# Written By Nick Clifton
#
# This file is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 3, or (at your option) any
# later version.
#
# This file 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
# General Public License for more details.
#
# Under Section 7 of GPL version 3, you are granted additional
# permissions described in the GCC Runtime Library Exception, version
# 3.1, as published by the Free Software Foundation.
#
# You should have received a copy of the GNU General Public License and
# a copy of the GCC Runtime Library Exception along with this program;
# see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
# <http://www.gnu.org/licenses/>.
/* An executable stack is *not* required for these functions. */
#if defined(__ELF__) && defined(__linux__)
.section .note.GNU-stack,"",%progbits
.previous
#endif
#ifdef __ARM_EABI__
/* Some attributes that are common to all routines in this file. */
/* Tag_ABI_align_needed: This code does not require 8-byte
alignment from the caller. */
/* .eabi_attribute 24, 0 -- default setting. */
/* Tag_ABI_align_preserved: This code preserves 8-byte
alignment in any callee. */
.eabi_attribute 25, 1
#endif /* __ARM_EABI__ */
# This file just makes sure that the .fini and .init sections do in
# fact return. Users may put any desired instructions in those sections.
# This file is the last thing linked into any executable.
# Note - this macro is complemented by the FUNC_START macro
# in crti.S. If you change this macro you must also change
# that macro match.
#
# Note - we do not try any fancy optimizations of the return
# sequences here, it is just not worth it. Instead keep things
# simple. Restore all the save registers, including the link
# register and then perform the correct function return instruction.
# We also save/restore r3 to ensure stack alignment.
.macro FUNC_END
#ifdef __thumb__
.thumb
pop {r3, r4, r5, r6, r7}
pop {r3}
mov lr, r3
#else
.arm
sub sp, fp, #40
ldmfd sp, {r4, r5, r6, r7, r8, r9, sl, fp, sp, lr}
#endif
#if defined __THUMB_INTERWORK__ || defined __thumb__
bx lr
#else
mov pc, lr
#endif
.endm
.section ".init"
;;
FUNC_END
.section ".fini"
;;
FUNC_END
# end of crtn.S