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[/] [openrisc/] [trunk/] [gnu-old/] [newlib-1.17.0/] [libgloss/] [m68k/] [sim-crt0.S] - Blame information for rev 816

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Line No. Rev Author Line
1 148 jeremybenn
/*
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 * crt0.S -- startup file for m68k-coff
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 *
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 * Copyright (c) 1995, 1996, 1998, 2001 Cygnus Support
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 *
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 * The authors hereby grant permission to use, copy, modify, distribute,
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 * and license this software and its documentation for any purpose, provided
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 * that existing copyright notices are retained in all copies and that this
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 * notice is included verbatim in any distributions. No written agreement,
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 * license, or royalty fee is required for any of the authorized uses.
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 * Modifications to this software may be copyrighted by their authors
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 * and need not follow the licensing terms described here, provided that
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 * the new terms are clearly indicated on the first page of each file where
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 * they apply.
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 */
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#include "asm.h"
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        .title "crt0.S for m68k-coff"
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#define STACKSIZE       0x4000
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/*
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 * Define an empty environment.
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 */
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        .data
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        .align 2
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SYM (environ):
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        .long 0
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        .align  2
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        .text
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/*
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 * These symbols are defined in C code, so they need to always be
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 * named with SYM because of the difference between object file formats.
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 */
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/* These are defined in C code. */
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        .extern SYM (main)
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        .extern SYM (exit)
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        .extern SYM (atexit)
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        .extern SYM(__do_global_dtors)
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/*
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 * These values are set in the linker script, so they must be
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 * explicitly named here without SYM.
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 */
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        .extern __stack
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        .extern __bss_start
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        .extern _end
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/*
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 * set things up so the application will run. This *must* be called start.
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 */
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        .global SYM (start)
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SYM (start):
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        /* See if user supplied their own stack (__stack != 0).  If not, then
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         * default to using the value of %sp as set by the ROM monitor.
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         */
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        movel   IMM(__stack), a0
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        cmpl    IMM(0), a0
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        jbeq    1f
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        movel   a0, sp
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1:
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        /* set up initial stack frame */
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        link    a6, IMM(-8)
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/*
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 * zero out the bss section.
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 */
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        movel   IMM(__bss_start), d1
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        movel   IMM(_end), d0
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        cmpl    d0, d1
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        jbeq    3f
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        movl    d1, a0
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        subl    d1, d0
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        subql   IMM(1), d0
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2:
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        clrb    (a0)+
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#if !defined(__mcoldfire__) && !defined(__mcf5200__)
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        dbra    d0, 2b
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        clrw    d0
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        subql   IMM(1), d0
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        jbcc    2b
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#else
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        subql   IMM(1), d0
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        jbpl    2b
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#endif
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3:
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/*
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 * call the main routine from the application to get it going.
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 * main (argc, argv, environ)
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 * we pass argv as a pointer to NULL.
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 */
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#ifdef ADD_DTORS
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        /* put __do_global_dtors in the atexit list so the destructors get run */
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        movel   IMM (SYM(__do_global_dtors)),(sp)
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        PICCALL SYM (atexit)
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#endif
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        movel   IMM (__FINI_SECTION__),(sp)
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        PICCALL SYM (atexit)
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        PICCALL __INIT_SECTION__
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        pea     0
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        PICPEA  SYM (environ),a0
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        pea     sp@(4)
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        pea     0
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        PICCALL SYM (main)
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        movel   d0, sp@-
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/*
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 * drop down into exit incase the user doesn't. This should drop
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 * control back to the ROM monitor, if there is one. This calls the
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 * exit() from the C library so the C++ tables get cleaned up right.
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 */
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        PICCALL SYM (exit)

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