glibc/sysdeps/s390/s390-64/start.S
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

107 lines
3.5 KiB
ArmAsm

/* Startup code compliant to the 64 bit S/390 ELF ABI.
Copyright (C) 2001-2021 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.
In addition to the permissions in the GNU Lesser General Public
License, the Free Software Foundation gives you unlimited
permission to link the compiled version of this file with other
programs, and to distribute those programs without any restriction
coming from the use of this file. (The GNU Lesser General Public
License restrictions do apply in other respects; for example, they
cover modification of the file, and distribution when not linked
into another program.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
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
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
/*
This is the canonical entry point, usually the first thing in the text
segment. Most registers' values are unspecified, except for:
%r14 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.
%r15 The stack contains the arguments and environment:
0(%r15) argc
8(%r15) argv[0]
...
(8*argc)(%r15) NULL
(8*(argc+1))(%r15) envp[0]
...
NULL
*/
.text
.globl _start
.type _start,@function
_start:
cfi_startproc
/* Mark r14 as undefined in order to stop unwinding here! */
cfi_undefined (r14)
/* Load argc and argv from stack. */
la %r4,8(%r15) # get argv
lg %r3,0(%r15) # get argc
/* Align the stack to a double word boundary. */
lghi %r0,-16
ngr %r15,%r0
/* Setup a stack frame and a parameter area. */
aghi %r15,-176 # make room on stack
xc 0(8,%r15),0(%r15) # clear back-chain
/* Set up arguments for __libc_start_main:
main, argc, argv, envp, _init, _fini, rtld_fini, stack_end
Note that envp will be determined later in __libc_start_main.
*/
stmg %r14,%r15,160(%r15) # store rtld_fini/stack_end to parameter area
la %r7,160(%r15)
lghi %r6,0 # Used to be fini.
lghi %r5,0 # Used to be init.
/* Ok, now branch to the libc main routine. */
#ifdef PIC
larl %r2,main@GOTENT # load pointer to main
lg %r2,0(%r2)
brasl %r14,__libc_start_main@plt
#else
larl %r2,main # load pointer to main
brasl %r14,__libc_start_main
#endif
/* Crash if __libc_start_main returns. */
.word 0
cfi_endproc
/* 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