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.code16
#ifndef REGPARM
# error "This file assumes -mregparm=3 -DREGPARM=3"
#endif
.section ".init","ax"
.globl _start
.type _start,@function
_start:
# Align the stack and make sure the high half is zero
andl $0xfff8,%esp
# Clear the .bss
cld
xorl %eax,%eax
movw $__bss_start,%di
movw $_end+3,%cx
subw %di,%cx
shrw $2,%cx
rep ; stosl
# Compute argc and argv (assumes REGPARM)
xorl %edx,%edx
movzbw 0x80,%bx
movb %dl,0x81(%bx) # Zero-terminate string
movb $0x81,%dl
pushl %eax # Make space for argv
movl %esp,%eax
calll __parse_argv
pushl %eax # argc
# Initialize malloc
# calll __init_memory_arena
# Now call main... (NOTE: gcc forces main to be regparm 0)
popl %eax # argc
popl %edx # argv
calll main
# Here %eax is the exit code, fall through into exit
.size _start,.-_start
.globl exit
.type exit,@function
exit:
# Exit code already in %eax
movb $0x4c,%ah # Terminate program
int $0x21
1: hlt
jmp 1b
.size exit,.-exit
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