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[/] [sardmips/] [trunk/] [PROGRAMMING_exception/] [crt0.S] - Blame information for rev 20

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/*
 * Starting point for everything (bootstrap)
 *
 * Initializes the stack pointer and jumps to main().
 */
 
#include "regdef.h"
 
        .text
        .align  2
        .globl  _start
        .ent    _start
_start:
        .set noreorder
 
        j       reset_handler
        nop
 
        j       handling_exception
        nop
 
 
reset_handler:
        /* Setup stack pointer */
        la      sp, _sp
 
        /* Clear bss */
        la      t0, 0x00000000      /* First address */
        la      t1, _end        /* Last  address */
 
        mfc0 k0, $12
        add k0, k0, 3
        mtc0 k0, $12
 
 
        jal     main
        nop
        j loop
        nop
 
handling_exception:
        nop
        mfc0 k0, $13
        mfc0 k1, $14
 
        srl k0, k0, 2
        andi k0, k0, 0x1F
 
        beq k0, $0, handling_interrupt
        nop
 
        add $11, $0, $0
        addiu $11, k1, 4
        mtc0 $11, $14
        eret
        nop
 
 
handling_interrupt:
        nop
        eret
        nop
 
        /* Run endless loop when the program terminates */
loop:
        j       loop
 
        .set    reorder
        .end    _start

Line No.	Rev	Author	Line
1	4	igorloi	`/*`
2			`* Starting point for everything (bootstrap)`
3			`*`
4			`* Initializes the stack pointer and jumps to main().`
5			`*/`
6
7			`#include "regdef.h"`
8
9			`.text`
10			`.align 2`
11			`.globl _start`
12			`.ent _start`
13			`_start:`
14			`.set noreorder`
15
16			`j reset_handler`
17			`nop`
18
19			`j handling_exception`
20			`nop`
21
22
23			`reset_handler:`
24			`/* Setup stack pointer */`
25			`la sp, _sp`
26
27			`/* Clear bss */`
28			`la t0, 0x00000000 /* First address */`
29			`la t1, _end /* Last address */`
30
31			`mfc0 k0, $12`
32			`add k0, k0, 3`
33			`mtc0 k0, $12`
34
35
36			`jal main`
37			`nop`
38			`j loop`
39			`nop`
40
41			`handling_exception:`
42			`nop`
43			`mfc0 k0, $13`
44			`mfc0 k1, $14`
45
46			`srl k0, k0, 2`
47			`andi k0, k0, 0x1F`
48
49			`beq k0, $0, handling_interrupt`
50			`nop`
51
52			`add $11, $0, $0`
53			`addiu $11, k1, 4`
54			`mtc0 $11, $14`
55			`eret`
56			`nop`
57
58
59			`handling_interrupt:`
60			`nop`
61			`eret`
62			`nop`
63
64			`/* Run endless loop when the program terminates */`
65			`loop:`
66			`j loop`
67
68			`.set reorder`
69			`.end _start`

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[/] [sardmips/] [trunk/] [PROGRAMMING_exception/] [crt0.S] - Blame information for rev 20