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/*

 * This is based on the file srt0.s provided with the binary

 * distribution of the SPARC Instruction Simulator (SIS) found

 * at ftp://ftp.estec.esa.nl/pub/ws/wsd/erc32.

 */

#include "asm.h"

        .data

        .align  8

SYM(environ):

        .long   0

        .text

        .globl SYM(start)

SYM(start):

        sethi   %hi(__stack), %g1

        or      %g1,%lo(__stack),%g1

        mov     %g1, %sp                ! set the stack pointer

        mov     %sp, %fp

        /* clear the bss */

        sethi %hi(__bss_start),%g2

        or    %g2,%lo(__bss_start),%g2  ! start of bss

        sethi %hi(_end),%g3

        or    %g3,%lo(_end),%g3         ! end of bss

        mov   %g0,%g1                   ! so std has two zeros

zerobss:

        std    %g0,[%g2]

        add    %g2,8,%g2

        cmp    %g2,%g3

        bleu,a zerobss

        nop

        /* move data segment to proper location */

#if 0

relocd:

        set (_endtext),%g2              ! g2 = start of data in aout file

        set (_environ),%g4              ! g4 = start of where data should go

        set (_edata),%g3                ! g3 = end of where data should go

        subcc   %g3, %g4, %g5           ! g5 = length of data

        subcc   %g4, %g2, %g0           ! need to relocate data ?

        ble     initok

        ld      [%g4], %g6

        subcc   %g6, 1, %g0

        be      initok

mvdata:

        subcc   %g5, 8, %g5

        ldd     [%g2 + %g5], %g6

        bg      mvdata

        std     %g6, [%g4 + %g5]

initok:

#endif

        call    SYM(__fix_ctors)

        nop

        call    SYM(main)

        nop

        /* call exit from the C library so atexit gets called, and the

         * C++ destructors get run. This calls our exit routine below    * when it's done.

         */

        call    SYM(exit)

        nop

        .globl  SYM(_exit)

SYM(_exit):

        set     0xdeadd00d, %o1         ! Magic number for simulator.

        ta      0                       ! Halt if _main returns ...

        nop