dwtoa --> qwtoa

[zedd151]

A conversion of Masm32 library function "dwtoa" for 64 bit.
The original (dwtoa) can be found in \masm32\m32lib\dwtoa.asm.

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; ---------------------------------------------------------------
 ; credts: Tim Roberts, Jibz for 'dwtoa', hutch for masm32.lib
 ; ---------------------------------------------------------------
 ;  Converted for 64 bit usage by zedd151 - tweaked by sinsi
 ; ---------------------------------------------------------------
 ; convert signed qword to ascii decimal string
 ; qwValue is value to be converted
 ; lpBuffer is the address of the receiving buffer
 ; EXAMPLE:
 ; invoke qwtoa, <signed qword>, addr buffer
 ; ---------------------------------------------------------------
 
qwtoa proc qwValue:qword, lpBuffer:qword
    mov rax,rcx
    mov r8,rcx
    mov r9,rdx
    push 0
    test rax,rax
    jnz not_zero
    push "0"
    jmp reverse ;<<<<<<<<<<<<<<<<<<<<
  not_zero:
    jns pos
    neg rax
  pos:
    mov rcx, 0CCCCCCCCCCCCCCCDh
  digit:
    mov r10, rax
    mul rcx
    shr rdx, 3
    mov rax, rdx
    lea rdx, [rdx*4+rdx]
    add rdx, rdx
    sub r10, rdx
    add r10b,"0"
    push r10
    test rax,rax
    jnz digit
    test r8,r8
    jns reverse
    push "-"
  reverse:
    pop rax
    mov [r9],al
    inc r9
    test al,al
    jnz reverse
  dtaexit:
    ret
qwtoa endp

Thank you sinsi for your assistance. 

[sinsi]

Nasty little bug if qwValue=0 

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    test rax,rax
    jnz not_zero
    push "0"
    jmp reverse ;<<<<<<<<<<<<<<<<<<<<


[zedd151]

Updated in first post.