41 lines
814 B
ArmAsm
41 lines
814 B
ArmAsm
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.define _begsig
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.globl _begsig
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.globl _vectab, _M
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mtype = 2 | M+mtype = &M.m_type
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_begsig:
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push ax | after interrupt, save all regs
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push bx
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push cx
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push dx
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push si
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push di
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push bp
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push ds
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push es
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mov bx,sp
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mov bx,18(bx) | bx = signal number
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mov ax,bx | ax = signal number
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dec bx | vectab[0] is for sig 1
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add bx,bx | pointers are two bytes on 8088
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mov bx,_vectab(bx) | bx = address of routine to call
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push _M+mtype | push status of last system call
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push ax | func called with signal number as arg
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call (bx)
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back:
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pop ax | get signal number off stack
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pop _M+mtype | restore status of previous system call
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pop es | signal handling finished
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pop ds
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pop bp
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pop di
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pop si
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pop dx
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pop cx
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pop bx
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pop ax
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pop dummy | remove signal number from stack
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iret
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.data
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dummy: .word 0
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