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[/] [openrisc/] [trunk/] [gnu-old/] [newlib-1.17.0/] [libgloss/] [m32r/] [crt0.S] - Blame information for rev 866

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Line No. Rev Author Line
1 148 jeremybenn
        .text
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        .balign 4
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        .global _start
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_start:
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        seth    sp, #shigh(_stack)
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        add3    sp, sp, #low(_stack)
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        ldi     fp, #0
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# Clear the BSS.  Do it in two parts for efficiency: longwords first
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# for most of it, then the remaining 0 to 3 bytes.
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        seth    r2, #shigh(__bss_start)
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        add3    r2, r2, #low(__bss_start); R2 = start of BSS
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        seth    r3, #shigh(_end)
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        add3    r3, r3, #low(_end)      ; R3 = end of BSS + 1
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        sub     r3, r2          ; R3 = BSS size in bytes
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        mv      r4, r3
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        srli    r4, #2          ; R4 = BSS size in longwords (rounded down)
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        ldi     r1, #0          ; clear R1 for longword store
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        addi    r2, #-4         ; account for pre-inc store
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        beqz    r4, .Lendloop1  ; any more to go?
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.Lloop1:
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        st      r1, @+r2        ; yep, zero out another longword
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        addi    r4, #-1         ; decrement count
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        bnez    r4, .Lloop1     ; go do some more
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.Lendloop1:
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        and3    r4, r3, #3      ; get no. of remaining BSS bytes to clear
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        addi    r2, #4          ; account for pre-inc store
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        beqz    r4, .Lendloop2  ; any more to go?
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.Lloop2:
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        stb     r1, @r2         ; yep, zero out another byte
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        addi    r2, #1          ; bump address
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        addi    r4, #-1         ; decrement count
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        bnez    r4, .Lloop2     ; go do some more
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.Lendloop2:
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# Run code in the .init section.
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# This will queue the .fini section to be run with atexit.
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        bl      __init
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# Call main, then exit.
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        bl      main
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        bl      exit
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# If that fails just loop.
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.Lexit:
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        bra     .Lexit

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