Question

in 80×86 assembly, is there an equivalent way to use ‘call’ like we do with ‘je’ ‘jl’ ‘jg’ ‘jne’ ?
i want to ‘call’ only if a condition is met .. ?

i want to implement :

cmp   eax, 1
je    something
; and continuing from here
; ....
; ...
jmp   end
something:
    ret

using je

thanks !

Answer 1

Not directly, no — the call instruction is always unconditional. Depending on what you’re doing with je/jl/etc., you may be able to get a (somewhat) similar effect with an indirect call like call [ebx], and having a jump table that contains the address of a ‘null’ procedure that will be called when ebx=0:

.code
proc1 proc
    ; whatever
null_proc::
    ret
proc1 endp

proc2 proc
   ; whatever
   ret
proc2 endp

main proc
    lea ebx, jmp_table[eax]
    call [ebx]
main endp

.data

jmp_table dd null_proc, proc1, proc2

end