[SOLVED] [MIPS] undefined reference $a3

[ne0h]

I'm getting some errors with this:

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.globl _start
.set noreorder
.ent _start

set_k1:
    li      $k1, 0

loop:
    nop
    j   loop
    nop

check_mem:
    addi    $a3, $a3, 1
    lw      $a2, $a3($a1)
    beq     $a2, $a0, check_mem
    nop

check_saved:
    lw      $a2, $a3($a1)
    beq     $a2, $a0, loop
    nop
    break

_start:
    li      $a0, 0x00000000
    li      $a1, 0x88000000
    li      $a3, -1

    j       check_mem
    nop

    sw      $a0, $a3($a1)
    
    j       check_saved
    nop
    
    

    

.set reorder
.end _start

Sorry, I'm trying to learn mips...
The error log:

main.o: In function `check_mem':
: undefined reference to `$a3'
main.o: In function `check_mem':
: undefined reference to `$a3'
main.o: In function `check_saved':
: undefined reference to `$a3'
main.o: In function `check_saved':
: undefined reference to `$a3'
main.o: In function `_start':
: undefined reference to `$a3'
main.o:: more undefined references to `$a3' follow
make: *** [build_asm] Error 1

[hlide]

no wonder... just have a look on a MIPS assembly instructions manual : there are something wrong in :

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lw      $a2, $a3($a1)

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sw      $a0, $a3($a1)

I'm letting you to guess what is wrong as an exercise.

[ne0h]

mmm,

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lw      $a2, $a3($a1)

this will load a word on a2 at address (a3 + a1), what's wrong?

[hlide]

such an instruction doesn't exist...

[NoEffex]

addu $t9, $a3, $a1
lw $a2, 0x0000($t9)

[ne0h]

I can't figure out where is my problem!
if is possible I want to know why I cannot do what I've done...
Thanks

[ab5000]

mmm,

Code: Select all

lw      $a2, $a3($a1)

this will load a word on a2 at address (a3 + a1), what's wrong?

take a look there: http://www.mrc.uidaho.edu/mrc/people/jf ... IPSir.html

[ne0h]

Ok, I've understand, thanks