OpenEuphoria

 
-- Jim here is a simple example to add two numbers. 
-- It only uses stack pointer and eax register. 
-- Notice that I have pushed the registers that I 
-- think that eu could be using. 
-- 
-- Try running the program on WIN98 and note the reurn value 
-- Then comment out any push/pop of any register or all the of registers 
-- and see what the result returns. 
-- 
 
 
include std/machine.e 
include std/dll.e 
-- 
constant add_numbers = allocate(19) 
poke(add_numbers, { 
    #56,                    --    0: push esi         ; 
    #57,                    --    1: push edi         ; 
    #52,                    --    2: push edx         ; 
    #55,                    --    3: push ebp         ; 
    #8B,#44,#24,#04,        --    4: mov eax, [esp+4] ; 
    #03,#44,#24,#08,        --    8: add eax, [esp+8] ; 
    #5D,                    --    C: pop ebp          ; 
    #5A,                    --    D: pop edx          ; 
    #5F,                    --    E: pop edi          ; 
    #5E,                    --    F: pop esi          ; 
    #C2,#08,#00})           --   10: ret 8            ; 
    -- you can change above to straight -->  #C3}) -- ret 
 
integer rid1 = define_c_func("", add_numbers , {33554436,33554436}, 33554436) 
? c_func(rid1,{15,17}) 
 
-- 
integer rid2 = define_c_func("", { '+',add_numbers }, {33554436,33554436}, 33554436) 
-- 
? c_func(rid2,{15,17}) 
-- 
if getc(0) then end if -- pause