x86 convert to lower case assembly

Question

This program is to convert a char pointer into lower case. I\'m using Visual Studio 2010.

This is from another question, but much simpler to read and mo

Answer 1

Your code can alter only the first char (or [edi], 20h) - the EDI does not increment.

EDIT: found this thread with workaround. Try using the 'dl' instead of al.

; move the token address to search for into EDI
; (not the *token, as would be with mov edi, [token])

mov edi, token      

LOWERCASE_TOKEN:            ;lowercase the token
  mov al, [edi]
  ; check for null-terminator here !
  cmp al, 0
  je GET_OUT
  or al, 20h
  mov dl, al
  mov [edi], dl
  inc edi
jmp LOWERCASE_TOKEN
GET_OUT: