Subversion Repositories scarts

/* crt0.S for the sparclet 701.

   At the moment, all the necessary syscalls are here.
   Convention has them in a separate file but libgloss is still in
   too much flux.  */

        .text

        .global start
start:

! zero bss

        sethi %hi(_end), %o1
        or %o1, %lo(_end), %o1
        sethi %hi(_edata), %o0
        or %o0, %lo (_edata), %o0
        sub %o1, %o0, %o1
Lzero_bss:
        subcc %o1, 4, %o1
        clr [%o0]
        bne Lzero_bss
        add %o0, 4, %o0

! set up argc, argv, envp (?)

        ld [%sp+64], %o0
        sll %o0, 2, %o2
        add %o2, 4, %o2
        add %sp, 68, %o1
        add %o1, %o2, %o2
        sethi %hi(_environ), %o3
        st %o2, [%o3+%lo(_environ)]

! call main, exit

        call _main
        sub %sp, 32, %sp
        call _exit
        nop

! void _exit (int rc)

        .global __exit
__exit:
        mov 1, %g1
        ta 0
! If that does not work, just loop forever.
Lloop_forever:
        b Lloop_forever
        nop

! int _open (char *, int)

        .global _open
_open:
        mov 5, %g1
        ta 0
        bcc Lnoerr
        nop
        b Lcerror
        nop

! int _close (int)

        .global _close
_close:
        mov 6, %g1
        ta 0
        bcc Lnoerr
        nop
        b Lcerror
        nop

! int read (int, char *, int)

        .global _read
_read:
        mov 3, %g1
        ta 0
        bcc Lnoerr
        nop
        b Lcerror
        nop

! int write (int, char *, int)

        .global _write
_write:
        mov 4, %g1
        ta 0
        bcc Lnoerr
        nop
        b Lcerror
        nop

Lnoerr:
        retl
        nop

Lcerror:
        sethi %hi(__impure_ptr), %g1
        st %o0, [%g1+%lo(__impure_ptr)]
        retl
        mov -1, %o0