[444] | 1 | /* |
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| 2 | * crt0.S -- startup file for D30V systems. |
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| 3 | * |
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| 4 | * Copyright (c) 1997 Cygnus Support |
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| 5 | * |
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| 6 | * The authors hereby grant permission to use, copy, modify, distribute, |
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| 7 | * and license this software and its documentation for any purpose, provided |
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| 8 | * that existing copyright notices are retained in all copies and that this |
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| 9 | * notice is included verbatim in any distributions. No written agreement, |
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| 10 | * license, or royalty fee is required for any of the authorized uses. |
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| 11 | * Modifications to this software may be copyrighted by their authors |
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| 12 | * and need not follow the licensing terms described here, provided that |
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| 13 | * the new terms are clearly indicated on the first page of each file where |
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| 14 | * they apply. |
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| 15 | */ |
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| 16 | |
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| 17 | .file "crt0.S" |
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| 18 | .text |
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| 19 | .globl _start |
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| 20 | .extern main |
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| 21 | .extern exit |
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| 22 | .extern __stack |
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| 23 | .extern __sbss_start |
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| 24 | .extern __sbss_end |
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| 25 | .extern __ebss_start |
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| 26 | .extern __ebss_end |
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| 27 | .extern __bss_start |
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| 28 | .extern __bss_end |
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| 29 | .extern memset |
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| 30 | .type _start,@function |
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| 31 | |
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| 32 | _start: or.l sp,r0,__stack |
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| 33 | |
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| 34 | /* Zero the .sbss area */ |
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| 35 | or.l r2,r0,__sbss_start |
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| 36 | or.l r4,r0,__sbss_end |
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| 37 | sub r4,r4,r2 || or.s r3,r0,0 |
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| 38 | bsrtnz.l r4,(memset) |
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| 39 | |
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| 40 | /* Zero the .ebss area */ |
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| 41 | or.l r2,r0,__ebss_start |
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| 42 | or.l r4,r0,__ebss_end |
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| 43 | sub r4,r4,r2 || or.s r3,r0,0 |
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| 44 | bsrtnz.l r4,(memset) |
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| 45 | |
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| 46 | /* Zero the .bss area */ |
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| 47 | or.l r2,r0,__bss_start |
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| 48 | or.l r4,r0,__bss_end |
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| 49 | sub r4,r4,r2 || or.s r3,r0,0 |
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| 50 | bsrtnz.l r4,(memset) |
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| 51 | |
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| 52 | or.s r2,r0,0 || or.s r3,r0,0 |
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| 53 | or r4,r0,0 || nop |
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| 54 | jsr.l (main) |
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| 55 | jsr.l (exit) |
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| 56 | .size _start,.-_start |
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