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.globl _tas
_tas:
movl $0xCAFEBABE, %eax
movl 4(%esp), %ecx
xchgl %eax, 0(%ecx)
ret
.globl setmcontext
setmcontext:
movl 4(%esp), %edx
movl 8(%edx), %fs
movl 12(%edx), %es
movl 16(%edx), %ds
movl 76(%edx), %ss
movl 20(%edx), %edi
movl 24(%edx), %esi
movl 28(%edx), %ebp
movl %esp, %ecx
movl 72(%edx), %esp
pushl 60(%edx) /* eip */
pushl 44(%edx) /* ecx */
pushl 48(%edx) /* eax */
movl 36(%edx), %ebx
movl 40(%edx), %edx
movl 12(%ecx), %eax
popl %eax
popl %ecx
ret
.globl getmcontext
getmcontext:
pushl %edx
movl 8(%esp), %edx
movl %fs, 8(%edx)
movl %es, 12(%edx)
movl %ds, 16(%edx)
movl %ss, 76(%edx)
movl %edi, 20(%edx)
movl %esi, 24(%edx)
movl %ebp, 28(%edx)
movl %ebx, 36(%edx)
movl $1, 48(%edx)
popl %eax
movl %eax, 40(%edx)
movl %ecx, 44(%edx)
movl (%esp), %eax /* eip */
movl %eax, 60(%edx)
movl %esp, %eax
addl $4, %eax /* setmcontext will re-push the eip */
movl %eax, 72(%edx)
movl 40(%edx), %edx
xorl %eax, %eax
ret
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