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        .text
        .global _start
        .type   _start,@function
        .stabs  "crt0.S",100,0,0,_start
        .stabs  "int:t(0,1)=r(0,1);-32768;32767;",128,0,0,0
        .stabs  "_start:F(0,1)",36,0,1,_start

_start:

; R14 always contains memory base address (0)

        ldi     r14,0

; Set the USER stack pointer.

        ldi     sp, 0x8000      ; SW
        mvtc    sp, psw         ; psw <- SW
        ldi     sp, _stack
        ldi     r0,0            ; zero arguments
        ldi     r1,0

; Clear the BSS.  Do it in two parts for efficiency: longwords first
; for most of it, then the remaining 0 to 3 bytes.

        ldi     r2, __bss_start ; R2 = start of BSS
        ldi     r3, _end        ; R3 = end of BSS + 1
        sub     r3, r2          ; R3 = BSS size in bytes
        mv      r4, r3
        srli    r4, 2           ; R4 = BSS size in longwords (rounded down)
loop1:
        cmpeqi  r4, 0           ; more longords to zero out?
        brf0t.s endloop1        ; nope
        st2w    r0, @r2+        ; yep, zero out another longword
        subi    r4, 1           ; decrement count
        bra.l   loop1           ; go do some more

endloop1:
        and3    r4, r3, 3       ; get no. of remaining BSS bytes to clear
loop2:
        cmpeqi  r4, 0           ; more bytes to zero out?
        brf0t.s endloop2        ; nope
        stb     r0, @r2         ; yep, zero out another byte
        addi    r2, 1           ; bump address
        subi    r4, 1           ; decrement count
        bra.s   loop2           ; go do some more
endloop2:
        
; Call main, then stop simulator

        bl      main
        bl      exit
        stop
.Lstart:
        .size   _start,.Lstart-_start
        .stabs  "",36,0,0,.Lstart-_start

        .section .stack
_stack: .long   1