square equations

.386
.model flat,stdcall
option   casemap:none
    include \masm32\include\masm32.inc
    include \masm32\include\kernel32.inc
    include \masm32\include\msvcrt.inc

    includelib \masm32\lib\masm32.lib
    includelib \masm32\lib\kernel32.lib
    includelib \masm32\lib\msvcrt.lib
.DATA
    FOUR dq 4

    WelcomeMes db 'Type a,b,c:',0ah,0dh,0
    Query db '%lf %lf %lf',0

    ANo_Roots db 'Expression has no roots!\n',0ah,0dh,0
    AOne_Root db 'Expression has one root! %lf',0ah,0dh,0
    ATwo_Roots db 'Expression has two roots! %lf, %lf',0ah,0dh,0

    _A dq ?
    _B dq ?
    _C dq ?
    _D dq ?

    _H dw ?

    _X1 dw ?
    _x2 dw ?
.CODE
START:
    finit

    push offset WelcomeMes
    call crt_printf

    push offset _C
    push offset _B
    push offset _A

    push offset Query

    call crt_scanf

    ;D = b * b + 4 * a * c

    fld _B
    fld _B
    fmul

    fstp _D

    fild FOUR
    fld _A
    fld _C

    fmul
    fmul

    fld _D

    fadd
    fldz
    fcom

    fstsw ax
    sahf

    fsqrt

    fstp _D

    ; ST(0) = 0, ST(1) = D

    je ONE_ROOT; ST(0) == ST(1) == 0
    jl NO_ROOTS
    jg TWO_ROOTS

ONE_ROOT:

    fld _B
    fld _B
    fld _B
    fmul
    fsub

    fld _D

    fadd

    fstp qword ptr [esp]

    push offset AOne_Root

    call crt_printf

    jmp END_POINT

TWO_ROOTS:

    fld _B
    fld _B
    fld _B
    fmul
    fsub

    fld _D

    fadd

    fstp qword ptr [esp]

    fld _B
    fld _B
    fld _B
    fmul
    fsub

    fld _D

    fsub

    fstp qword ptr [esp + 8]

    push offset ATwo_Roots

    call crt_printf

    jmp END_POINT

NO_ROOTS:

    push offset ANo_Roots

    call crt_printf

    jmp END_POINT

END_POINT:

    push 0
    call ExitProcess
END  START