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        .text

        .balign 4

        .global _start

_start:

        seth    sp, #shigh(_stack)

        add3    sp, sp, #low(_stack)

        ldi     fp, #0

# Clear the BSS.  Do it in two parts for efficiency: longwords first

# for most of it, then the remaining 0 to 3 bytes.

        seth    r2, #shigh(__bss_start)

        add3    r2, r2, #low(__bss_start); R2 = start of BSS

        seth    r3, #shigh(_end)

        add3    r3, r3, #low(_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)

        ldi     r1, #0          ; clear R1 for longword store

        addi    r2, #-4         ; account for pre-inc store

        beqz    r4, .Lendloop1  ; any more to go?

.Lloop1:

        st      r1, @+r2        ; yep, zero out another longword

        addi    r4, #-1         ; decrement count

        bnez    r4, .Lloop1     ; go do some more

.Lendloop1:

        and3    r4, r3, #3      ; get no. of remaining BSS bytes to clear

        addi    r2, #4          ; account for pre-inc store

        beqz    r4, .Lendloop2  ; any more to go?

.Lloop2:

        stb     r1, @r2         ; yep, zero out another byte

        addi    r2, #1          ; bump address

        addi    r4, #-1         ; decrement count

        bnez    r4, .Lloop2     ; go do some more

.Lendloop2:

# Run code in the .init section.

# This will queue the .fini section to be run with atexit.

        bl      __init

# Call main, then exit.

        bl      main

        bl      exit

# If that fails just loop.

.Lexit:

        bra     .Lexit