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274895575e
Ensure that all objects in ARM EABI glibc have the proper EABI build attributes to indicate that 8-byte stack alignment is required and preserved. (GNU ld does not currently give errors for mixing code requiring 8-byte alignment - such as anything built with GCC - and code not marked as preserving it, because of the prevalence of assembly code without proper markers to indicate that alignment is preserved. The ARM RealView linker does give such errors.) The bulk of the markers are accomplished by the change to sysdep.h, but a few .S files do not include sysdep.h. In the case of internal_accept4.S, no code is generated because EABI does not have socketcall, but for completeness a dummy file with the right attributes is used to override the default version in libc. * sysdeps/arm/sysdep.h: (Tag_ABI_align8_preserved, Tag_ABI_align8_needed): Attributes added. * sysdeps/arm/elf/start.S: Likewise. * sysdeps/arm/eabi/abi-note.S: New file. * sysdeps/unix/sysv/linux/arm/eabi/internal_accept4.S: New file.
157 lines
4.4 KiB
ArmAsm
157 lines
4.4 KiB
ArmAsm
/* Startup code for ARM & ELF
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Copyright (C) 1995, 1996, 1997, 1998, 2001, 2002, 2005, 2008
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Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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In addition to the permissions in the GNU Lesser General Public
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License, the Free Software Foundation gives you unlimited
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permission to link the compiled version of this file with other
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programs, and to distribute those programs without any restriction
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coming from the use of this file. (The GNU Lesser General Public
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License restrictions do apply in other respects; for example, they
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cover modification of the file, and distribution when not linked
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into another program.)
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Note that people who make modified versions of this file are not
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obligated to grant this special exception for their modified
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versions; it is their choice whether to do so. The GNU Lesser
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General Public License gives permission to release a modified
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version without this exception; this exception also makes it
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possible to release a modified version which carries forward this
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exception.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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/* This is the canonical entry point, usually the first thing in the text
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segment.
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Note that the code in the .init section has already been run.
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This includes _init and _libc_init
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At this entry point, most registers' values are unspecified, except:
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a1 Contains a function pointer to be registered with `atexit'.
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This is how the dynamic linker arranges to have DT_FINI
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functions called for shared libraries that have been loaded
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before this code runs.
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sp The stack contains the arguments and environment:
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0(sp) argc
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4(sp) argv[0]
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...
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(4*argc)(sp) NULL
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(4*(argc+1))(sp) envp[0]
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...
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NULL
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*/
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#if defined(__ARM_EABI__)
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/* Tag_ABI_align8_preserved: This code preserves 8-byte
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alignment in any callee. */
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.eabi_attribute 25, 1
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/* Tag_ABI_align8_needed: This code may require 8-byte alignment from
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the caller. */
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.eabi_attribute 24, 1
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#endif
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#if defined(__thumb2__)
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.thumb
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.syntax unified
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#endif
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.text
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.globl _start
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.type _start,#function
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_start:
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#if !defined(__USING_SJLJ_EXCEPTIONS__)
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/* Protect against unhandled exceptions. */
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.fnstart
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#endif
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/* Clear the frame pointer and link register since this is the outermost frame. */
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mov fp, #0
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mov lr, #0
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/* Pop argc off the stack and save a pointer to argv */
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ldr a2, [sp], #4
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mov a3, sp
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/* Push stack limit */
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str a3, [sp, #-4]!
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/* Push rtld_fini */
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str a1, [sp, #-4]!
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#ifdef SHARED
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ldr sl, .L_GOT
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adr a4, .L_GOT
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add sl, sl, a4
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ldr ip, .L_GOT+4 /* __libc_csu_fini */
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ldr ip, [sl, ip]
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str ip, [sp, #-4]! /* Push __libc_csu_fini */
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ldr a4, .L_GOT+8 /* __libc_csu_init */
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ldr a4, [sl, a4]
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ldr a1, .L_GOT+12 /* main */
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ldr a1, [sl, a1]
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/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
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/* Let the libc call main and exit with its return code. */
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bl __libc_start_main(PLT)
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#else
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/* Fetch address of __libc_csu_fini */
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ldr ip, =__libc_csu_fini
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/* Push __libc_csu_fini */
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str ip, [sp, #-4]!
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/* Set up the other arguments in registers */
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ldr a1, =main
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ldr a4, =__libc_csu_init
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/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
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/* Let the libc call main and exit with its return code. */
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bl __libc_start_main
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#endif
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/* should never get here....*/
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bl abort
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#ifdef SHARED
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.L_GOT:
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.word _GLOBAL_OFFSET_TABLE_ - .L_GOT
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.word __libc_csu_fini(GOT)
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.word __libc_csu_init(GOT)
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.word main(GOT)
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#endif
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#if !defined(__USING_SJLJ_EXCEPTIONS__)
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.cantunwind
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.fnend
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#endif
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/* Define a symbol for the first piece of initialized data. */
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.data
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.globl __data_start
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__data_start:
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.long 0
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.weak data_start
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data_start = __data_start
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