Location counter??

[jj2007]

(Zeroing local variables taking into account how many GPR was pushed)

The MasmBasic equivalent. In contrast to RtlZeroMemory, no regs are trashed here - think of fastcall...

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include \masm32\include\masm32rt.inc

.code
start: call MySub
exit

MySub Proc
LOCAL Var01 :DWORD
LOCAL Var02[10h]:BYTE
call ClearLocVars
push esi
push edi
xor ebx, ebx
pop edi
pop esi
ret
MySub endp

ClearLocVars proc ; put "call ClearLocals" as first instruction after LOCALS - eax unchanged on exit
 push eax ; do not use with uses esi etc - push them manually behind the call!
 lea eax, [esp+8] ; pushed eax and ret address
 mov esp, ebp ; base page of calling procedure
 align 4
@@:
 push 0
 cmp esp, eax
 ja @B
 sub esp, 8 ; 19 bytes with align 4
 pop eax
 ret
ClearLocVars endp
end start


[Ficko]

A little correction:

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ZEROSUBVARS MACRO Subroutine:REQ
mov ecx, ebp
lea eax, [esp+(($-Subroutine)-8)*4]
sub ecx, eax
invoke RtlZeroMemory,eax,ecx
ENDM


That way  "ZEROSUBVARS" can be put  immediately as the first "command" after "locals". :wink