I have been porting some basic code of late and this one helped to make some of it easier and faster.
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charfill PROTO :DWORD,:DWORD,:DWORD
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; EXAMPLE
local spc$ :DWORD ; DWORD handle for string
.....
mov spc$, space$(1024) ; allocate a space filled string
.....
free$ spc$ ; deallocate it when finished
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space$ MACRO bcnt
push esi
mov esi, alloc$(bcnt)
invoke charfill,esi,bcnt,32
mov eax, esi
pop esi
EXITM <eax> ;; dealloc with free$
ENDM
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OPTION PROLOGUE:NONE
OPTION EPILOGUE:NONE
align 16
charfill proc buff:DWORD,bcnt:DWORD,char:DWORD
mov ecx, [esp+4] ; data address
mov edx, [esp+8] ; fill count
mov eax, [esp+12] ; fill character
sub ecx, 1
@@:
add ecx, 1
mov [ecx], al
sub edx, 1
jnz @B
ret 12
charfill endp
OPTION PROLOGUE:PrologueDef
OPTION EPILOGUE:EpilogueDef
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hi,
it should be a bit faster if you accept 07FFFFFFFh as max value for fill count :
mov ecx, [esp+4] ; data address
mov edx, [esp+8] ; fill count
mov eax, [esp+12] ; fill character
add ecx,edx
neg edx
@@:
mov [edx+ecx], al
add edx, 1
jnz @B