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|
#
# This is a startup for GCC compiling to an ELF executable.
#
#
.file "cstartup.s"
# void (*__cleanup)() = 0;
.globl __cleanup
.data
.align 4
.type __cleanup,@object
.size __cleanup,4
__cleanup:
.long 0
.globl errno
.align 4
.type errno,@object
.size errno,4
errno:
.long 0
# char ** environ;
.comm environ,4,4
.text
.align 16
.globl __cstartup
.type __cstartup,@function
__cstartup: # Crt0 startup (Linux style)
cmpl $0,(%esp)
jz call_exit # If argc == 0 this is being called by ldd, exit.
popl %ecx
movl %esp,%ebx # Points to the arguments
movl %esp,%eax
movl %ecx,%edx
addl %edx,%edx
addl %edx,%edx
addl %edx,%eax
addl $4,%eax # Now points to environ.
pushl %eax # envp
pushl %ebx # argp
pushl %ecx # argc
# mov 8(%esp),%eax
mov %eax,environ
call main
push %eax # Main has returned,
call_exit:
call exit # return val and call exit();
bad_exit:
jmp bad_exit # Exit returned !!
# Exit - call __cleanup then _exit
.align 16
.globl exit
.type exit,@function
exit:
pushl %ebp
movl %esp,%ebp
pushl %ebx
movl 8(%ebp),%ebx
movl __cleanup,%eax
testl %eax,%eax
je .L8
pushl %ebx
call *%eax
addl $4,%esp
.L8:
pushl %ebx
call _exit
jmp bad_exit
# _exit is an alias for __exit
.align 16
.globl _exit
.type _exit,@function
_exit:
jmp __exit
|
