c++ - What is wrong with using inline functions? -

-

while convenient use inline functions @ situations,

are there drawbacks inline functions?

conclusion:

apparently, there nothing wrong using inline functions.

but worth noting following points!

  • overuse of inlining can make programs slower. depending on function's size, inlining can cause code size increase or decrease. inlining small accessor function decrease code size while inlining large function can dramatically increase code size. on modern processors smaller code runs faster due better use of instruction cache. - google guidelines

  • the speed benefits of inline functions tend diminish function grows in size. @ point overhead of function call becomes small compared execution of function body, , benefit lost - source

  • there few situations inline function may not work:

    • for function returning values; if return statement exists.
    • for function not returning values; if loop, switch or goto statement exists.
    • if function recursive. -source

  • the __inline keyword causes function inlined if specify optimize option. if optimize specified, whether or not __inline honored depends on setting of inline optimizer option. default, inline option in effect whenever optimizer run. if specify optimize , must specify noinline option if want __inline keyword ignored. -source

it worth pointing out inline keyword hint compiler. compiler may ignore inline , generate code function someplace.

the main drawback inline functions can increase size of executable (depending on number of instantiations). can problem on platforms (eg. embedded systems), if function recursive.

i'd recommend making inline'd functions very small - speed benefits of inline functions tend diminish function grows in size. @ point overhead of function call becomes small compared execution of function body, , benefit lost.


Comments

Post a Comment

Popular posts from this blog

c++ - How do I get a multi line tooltip in MFC -

-
right now, have tool tip pops when hover on edit box. problem tool tip contains multiple error messages , in 1 long line. need have each error message on own line. error messages contained in cstring new line seperating them. my existing code below. bool ontooltiptext(uint, nmhdr* pnmhdr, lresult* presult) { assert(pnmhdr->code == ttn_needtexta || pnmhdr->code == ttn_needtextw); // need handle both ansi , unicode versions of message tooltiptexta* pttta = (tooltiptexta*)pnmhdr; tooltiptextw* ptttw = (tooltiptextw*)pnmhdr; // tchar szfulltext[256]; cstring strtiptext=_t(""); uint nid = pnmhdr->idfrom; if (pnmhdr->code == ttn_needtexta && (pttta->uflags & ttf_idishwnd) || pnmhdr->code == ttn_needtextw && (ptttw->uflags & ttf_idishwnd)) { // idfrom hwnd of tool nid = ::getdlgctrlid((hwnd)nid); } //m_errprojaccel[ch] contains 1 or more error messages each...
Read more

asp.net - In javascript how to find the height and width -

-
i having .aspx , masterpage page. in masterpage loading aspx page . in aspx page design using generating table structure using code-behind server in javascript how find height , width . regards, kumar if you're looking table height , width, should it var tbl = document.getelementbyid('tbldemo'); alert(tbl.offsetwidth + '\n' + tbl.offsetheight);
Read more

c# - DataTable to EnumerableRowCollection -

-
i have datatable according client requirement can contain invalid date "00/00/1999",null,empty string.(typed datset) when collect them enumerables wish convert of invalid forms empty string. (i.e) enumerablerowcollection<datarow> query = order in _table.asenumerable() select new { orderdate= string.isnullorempty(convert.tostring(order.field<datetime>("orderdate")) || (how check date invalid date) ? string.empty : order.field<datetime>("orderdate") } how check whether date valid date or not? datetime.tryparse...like given current code: datetime date; enumerablerowcollection<datarow> query = order in _table.asenumerable() select new { orderdate= string.isnullorempty(convert.tostring(order.field<datetime>("orderdate")) || !datetime.tryparse(convert.tostring(order.field<datetime...
Read more