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! crt1.s for sparc & sparcv9 (SunOS 5)

!   Copyright (C) 1992, 2009 Free Software Foundation, Inc.

!   Written By David Vinayak Henkel-Wallace, June 1992

!

! 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

! .

! This file takes control of the process from the kernel, as specified

! in section 3 of the SVr4 ABI.

! This file is the first thing linked into any executable.

#ifdef __sparcv9

#define CPTRSIZE        8

#define CPTRSHIFT       3

#define STACK_BIAS      2047

#define ldn             ldx

#define stn             stx

#define setn(s, scratch, dst)   setx s, scratch, dst

#else

#define CPTRSIZE        4

#define CPTRSHIFT       2

#define STACK_BIAS      0

#define ldn             ld

#define stn             st

#define setn(s, scratch, dst)   set s, dst

#endif

        .section        ".text"

        .proc   022

        .global _start

_start:

        mov     0, %fp          ! Mark bottom frame pointer

        ldn     [%sp + (16 * CPTRSIZE) + STACK_BIAS], %l0       ! argc

        add     %sp, (17 * CPTRSIZE) + STACK_BIAS, %l1          ! argv

        ! Leave some room for a call.  Sun leaves 32 octets (to sit on

        ! a cache line?) so we do too.

#ifdef __sparcv9

        sub     %sp, 48, %sp

#else

        sub     %sp, 32, %sp

#endif

        ! %g1 may contain a function to be registered w/atexit

        orcc    %g0, %g1, %g0

#ifdef __sparcv9

        be      %xcc, .nope

#else

        be      .nope

#endif

        mov     %g1, %o0

        call    atexit

        nop

.nope:

        ! Now make sure constructors and destructors are handled.

        setn(_fini, %o1, %o0)

        call    atexit, 1

        nop

        call    _init, 0

        nop

        ! We ignore the auxiliary vector; there is no defined way to

        ! access those data anyway.  Instead, go straight to main:

        mov     %l0, %o0        ! argc

        mov     %l1, %o1        ! argv

#ifdef GCRT1

        setn(___Argv, %o4, %o3)

        stn     %o1, [%o3]      ! *___Argv

#endif

        ! Skip argc words past argv, to env:

        sll     %l0, CPTRSHIFT, %o2

        add     %o2, CPTRSIZE, %o2

        add     %l1, %o2, %o2   ! env

        setn(_environ, %o4, %o3)

        stn     %o2, [%o3]      ! *_environ

        call    main, 4

        nop

        call    exit, 0

        nop

        call    _exit, 0

        nop

        ! We should never get here.

        .type   _start,#function

        .size   _start,.-_start