Hi,
Just found Arnaud have explained the problems, so here give you an
example I have written one year ago:
# File: hello.s -- Say Hello to MIPS Assembly Language Programmer
# Author: falcon <wuzhangjin@gmail.com>, 2009/01/17
# Ref:
# [*] http://www.tldp.org/HOWTO/Assembly-HOWTO/mips.html
# [*] MIPS Assembly Language Programmer's Guide
# [*] See MIPS Run Linux(second version)
# Compile:
# $ gcc -o hello hello.s
# or
# $ as -o hello.o hello.s
# $ ld -e main -o hello hello.o
.text
.globl main
main:
.set noreorder
.cpload $gp # setup the pointer to global data
.set reorder
# print sth. via sys_write
li $a0, 1 # print to standard ouput
la $a1, stradr # set the string address
lw $a2, strlen # set the string length
li $v0, 4004 # index of sys_write:
# __NR_write in /usr/include/asm/unistd.h
syscall # causes a system call trap.
# exit via sys_exit
move $a0, $0 # exit status as 0
li $v0, 4001 # index of sys_exit
# __NR_exit in /usr/include/asm/unistd.h
syscall
.rdata
stradr: .asciiz "hello, world!\n"
strlen: .word . - stradr # current address - the string address
# end
Regards,
Wu Zhangjin
On Fri, 2010-05-21 at 16:46 +0500, adnan iqbal wrote:
> Hi all,
>
> I am trying to compile/link/execute following very simple program in
> debian/MIPS (Tried on Qemu and Octeon). I am getting errors while
> executing the program. gdb also shows a strange behavior showing
> program entrypoint somehere in data segement. Any help getting this
> sorted out shall be appreciated.
>
> Regards
> Adnan
>
> Commands used to compile/link
> ----------------------------------------------------
> $ as hello.s -o hello.o
> $ld hello.o -o hello
> $ ./hello
>
>
> The code
> ---------------
> .data
> str:
> .asciiz "hello world\n"
> .text
> .globl __start
>
> __start:
> jal f2
> la $4,str
> li $2,4
> syscall
>
> ## terminate program via _exit () system call
> li $2, 10
> syscall
> f2:
> add $8,$8,$0
> jr $31
>
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