33 lines
801 B
ArmAsm
33 lines
801 B
ArmAsm
#
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! alloca() - allocate space on the stack Author: Kees J. Bot
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! 2 Dec 1993
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.sect .text; .sect .rom; .sect .data; .sect .bss
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.sect .text
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.align 16
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.define _alloca
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_alloca:
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#if __ACK__
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pop ecx ! Return address
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pop eax ! Bytes to allocate
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add eax, 2*4+3 ! Add space for two saved register variables
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andb al, 0xFC ! Align
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mov ebx, esp ! Keep current esp
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sub esp, eax ! Lower stack
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mov eax, esp ! Return value
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push 4(ebx) ! Push what is probably the saved esi
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push (ebx) ! Saved edi
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! Now ACK can still do:
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! pop edi; pop esi; leave; ret
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push eax ! Dummy argument
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jmp ecx
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#else
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pop ecx ! Return address
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pop eax ! Bytes to allocate
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add eax, 3
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andb al, 0xFC ! Align
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sub esp, eax ! Lower stack
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mov eax, esp ! Return value
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push eax ! Dummy argument
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jmp ecx
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#endif
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